• dr hab. Stanisław Duber
Stanowisko: Prof.Uczelni
Jednostka: Instytut Nauk o Ziemi
Adres: Śląskie Międzyuczelniane Centrum Edukacji i Badań Interdyscyplinarnych, Chorzów, ul.75 Pułku Piechoty 1
Piętro: przyziemie
Numer pokoju: P30, bud.H
Telefon: (32) 3493 933
E-mail: stanislaw.duber@us.edu.pl
Spis publikacji: Spis wg CINiBA
Spis publikacji: Spis wg OPUS
Scopus Author ID: 6701523650
Publikacje z bazy Scopus
2018
Jurkiewicz, K.; Pawlyta, M.; Zygadło, D.; Chrobak, D.; Duber, S.; Wrzalik, R.; Ratuszna, A.; Burian, A.
Evolution of glassy carbon under heat treatment: Correlation structure–mechanical properties Journal Article
In: Journal of Materials Science, vol. 53, no. 5, pp. 3509-3523, 2018, ISSN: 00222461, (69).
@article{2-s2.0-85032838513,
title = {Evolution of glassy carbon under heat treatment: Correlation structure–mechanical properties},
author = { K. Jurkiewicz and M. Pawlyta and D. Zygadło and D. Chrobak and S. Duber and R. Wrzalik and A. Ratuszna and A. Burian},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85032838513&doi=10.1007%2fs10853-017-1753-7&partnerID=40&md5=ee60e565746a712d0d2df5c691e684e5},
doi = {10.1007/s10853-017-1753-7},
issn = {00222461},
year = {2018},
date = {2018-01-01},
journal = {Journal of Materials Science},
volume = {53},
number = {5},
pages = {3509-3523},
publisher = {Springer New York LLC},
abstract = {In order to accommodate an increasing demand for glassy carbon products with tailored characteristics, one has to understand the origin of their structure-related properties. In this work, through the use of high-resolution transmission electron microscopy, Raman spectroscopy, and electron energy loss spectroscopy it has been demonstrated that the structure of glassy carbon at different stages of the carbonization process resembles the curvature observed in fragments of nanotubes, fullerenes, or nanoonions. The measured nanoindentation hardness and reduced Young’s modulus change as a function of the pyrolysis temperature from the range of 600–2500 °C and reach maximum values for carbon pyrolyzed at around 1000 °C. Essentially, the highest values of the mechanical parameters for glassy carbon manufactured at that temperature can be related to the greatest amount of non-planar sp2-hybridized carbon atoms involved in the formation of curved graphene-like layers. Such complex labyrinth- like structure with sp2-type bonding would be rigid and hard to break that explains the glassy carbon high strength and hardness. © The Author(s) 2017.},
note = {69},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In order to accommodate an increasing demand for glassy carbon products with tailored characteristics, one has to understand the origin of their structure-related properties. In this work, through the use of high-resolution transmission electron microscopy, Raman spectroscopy, and electron energy loss spectroscopy it has been demonstrated that the structure of glassy carbon at different stages of the carbonization process resembles the curvature observed in fragments of nanotubes, fullerenes, or nanoonions. The measured nanoindentation hardness and reduced Young’s modulus change as a function of the pyrolysis temperature from the range of 600–2500 °C and reach maximum values for carbon pyrolyzed at around 1000 °C. Essentially, the highest values of the mechanical parameters for glassy carbon manufactured at that temperature can be related to the greatest amount of non-planar sp2-hybridized carbon atoms involved in the formation of curved graphene-like layers. Such complex labyrinth- like structure with sp2-type bonding would be rigid and hard to break that explains the glassy carbon high strength and hardness. © The Author(s) 2017.
2017
Woźnica, N.; Hawełek, Ł.; Duber, S.; Fischer, H. E.; Honkimäki, V.; Pawlyta, M.; Bulou, A.; Burian, A.
The atomic scale structure of saccharose-based carbons Journal Article
In: Philosophical Magazine, vol. 97, no. 20, pp. 1675-1697, 2017, ISSN: 14786435, (5).
@article{2-s2.0-85017578974,
title = {The atomic scale structure of saccharose-based carbons},
author = { N. Woźnica and Ł. Hawełek and S. Duber and H.E. Fischer and V. Honkimäki and M. Pawlyta and A. Bulou and A. Burian},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85017578974&doi=10.1080%2f14786435.2017.1313465&partnerID=40&md5=26837ccb041d97f613638e0e94f2da15},
doi = {10.1080/14786435.2017.1313465},
issn = {14786435},
year = {2017},
date = {2017-01-01},
journal = {Philosophical Magazine},
volume = {97},
number = {20},
pages = {1675-1697},
publisher = {Taylor and Francis Ltd.},
abstract = {Activated carbons (ACs) have a wide range of applications, in which the largely expanded specific surface plays a major role. The question of their structure came back to the limelight with the discovery of nanotubes fullerenes, which suggested that curved surfaces may be present in their structure and which incorporates well into the ideas of ACs porous structure. The source of those curved surfaces is atomic defects present inside the in-plane graphitic honeycomb lattice. Such defects have a crucial influence on the macroscopic morphology as well as physical properties of the material. The activated carbon (AC) in this work was derived from carbonised saccharose by activation with NaOH. Both materials–before and after activation were investigated. The main methods used in this study are wide angle neutron scattering and wide angle X-ray scattering combined with computer simulations. Confirmation of the proposed structures was sought with high-resolution transmission electron microscopy and Raman scattering. In this case, the use of classical crystallography to interpret experimental data was impossible due to the lack of periodic three-dimensional symmetry. Due to this fact, the data was analysed both in real and reciprocal space in the form of a pair correlation function and a structure factor. The experimental data were compared with calculated atomistic models. As a validation, the discrepancy factor between the theoretically and experimentally obtained functions was used. The presented innovative approach can be applied to different carbon materials with varying degrees of disorder. © 2017 Informa UK Limited, trading as Taylor & Francis Group.},
note = {5},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Activated carbons (ACs) have a wide range of applications, in which the largely expanded specific surface plays a major role. The question of their structure came back to the limelight with the discovery of nanotubes fullerenes, which suggested that curved surfaces may be present in their structure and which incorporates well into the ideas of ACs porous structure. The source of those curved surfaces is atomic defects present inside the in-plane graphitic honeycomb lattice. Such defects have a crucial influence on the macroscopic morphology as well as physical properties of the material. The activated carbon (AC) in this work was derived from carbonised saccharose by activation with NaOH. Both materials–before and after activation were investigated. The main methods used in this study are wide angle neutron scattering and wide angle X-ray scattering combined with computer simulations. Confirmation of the proposed structures was sought with high-resolution transmission electron microscopy and Raman scattering. In this case, the use of classical crystallography to interpret experimental data was impossible due to the lack of periodic three-dimensional symmetry. Due to this fact, the data was analysed both in real and reciprocal space in the form of a pair correlation function and a structure factor. The experimental data were compared with calculated atomistic models. As a validation, the discrepancy factor between the theoretically and experimentally obtained functions was used. The presented innovative approach can be applied to different carbon materials with varying degrees of disorder. © 2017 Informa UK Limited, trading as Taylor & Francis Group.
Jurkiewicz, K.; Duber, S.; Fischer, H. E.; Burian, A.
Modelling of glass-like carbon structure and its experimental verification by neutron and X-ray diffraction Journal Article
In: Journal of Applied Crystallography, vol. 50, no. 1, pp. 36-48, 2017, ISSN: 00218898, (38).
@article{2-s2.0-85011655377,
title = {Modelling of glass-like carbon structure and its experimental verification by neutron and X-ray diffraction},
author = { K. Jurkiewicz and S. Duber and H.E. Fischer and A. Burian},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85011655377&doi=10.1107%2fS1600576716017660&partnerID=40&md5=38602df7f5a9cccf27ebf54da1c7e996},
doi = {10.1107/S1600576716017660},
issn = {00218898},
year = {2017},
date = {2017-01-01},
journal = {Journal of Applied Crystallography},
volume = {50},
number = {1},
pages = {36-48},
publisher = {International Union of Crystallography},
abstract = {Glass-like carbon is a well known carbon form that still poses many challenges for structural characterization owing to a very complex internal atomic organization. Recent research suggests that glassy carbon has a fullerenerelated structure that evolves with the synthesis temperature. This article reports on direct evidence of curved planes in glassy carbons using neutron and X-ray diffraction measurements and their analysis in real space using the atomic pair distribution function formalism. Changes in the structure including the degree of curvature of the non-graphitizing glassy carbons as a function of the pyrolysis temperature in the range 800-2500°C (1073-2773 K) are studied using optimized models of the atomic structure. Averaged models of single coherent scattering domains as well as larger structural fragments consisting of thousands of atoms were relaxed using classical molecular dynamics. For such models the diffraction intensities and the pair distribution functions were computed. The compatibility of the computer-generated models was verified by comparison of the simulations with the experimental diffraction data in both reciprocal and real spaces. On the basis of features of the developed structural models for glasslike carbons, the origin of the properties such as high strength and hardness and low gas permeability can be better understood. © 2017 International Union of Crystallography.},
note = {38},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Glass-like carbon is a well known carbon form that still poses many challenges for structural characterization owing to a very complex internal atomic organization. Recent research suggests that glassy carbon has a fullerenerelated structure that evolves with the synthesis temperature. This article reports on direct evidence of curved planes in glassy carbons using neutron and X-ray diffraction measurements and their analysis in real space using the atomic pair distribution function formalism. Changes in the structure including the degree of curvature of the non-graphitizing glassy carbons as a function of the pyrolysis temperature in the range 800-2500°C (1073-2773 K) are studied using optimized models of the atomic structure. Averaged models of single coherent scattering domains as well as larger structural fragments consisting of thousands of atoms were relaxed using classical molecular dynamics. For such models the diffraction intensities and the pair distribution functions were computed. The compatibility of the computer-generated models was verified by comparison of the simulations with the experimental diffraction data in both reciprocal and real spaces. On the basis of features of the developed structural models for glasslike carbons, the origin of the properties such as high strength and hardness and low gas permeability can be better understood. © 2017 International Union of Crystallography.
2016
Jurkiewicz, K.; Duber, S.; Burian, A.
Paracrystalline Structure of Glass-Like Carbons Journal Article
In: International Journal of Applied Glass Science, vol. 7, no. 3, pp. 355-363, 2016, ISSN: 20411286, (6).
@article{2-s2.0-84960145146,
title = {Paracrystalline Structure of Glass-Like Carbons},
author = { K. Jurkiewicz and S. Duber and A. Burian},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84960145146&doi=10.1111%2fijag.12186&partnerID=40&md5=57fe6231e897ddbc23ece8b844dffec4},
doi = {10.1111/ijag.12186},
issn = {20411286},
year = {2016},
date = {2016-01-01},
journal = {International Journal of Applied Glass Science},
volume = {7},
number = {3},
pages = {355-363},
publisher = {Blackwell Publishing Inc.},
abstract = {This study reports on structural characterization of a series of glass-like carbons obtained by pyrolysis of polyfurfuryl alcohol at 600, 800, 980, and 2700°C. The atomic scale structure of the prepared materials has been studied using wide-angle X-ray scattering technique. The acquired diffraction data were analyzed in reciprocal space as the structure factor and in real space in the form of the pair distribution function to reveal the structural attributes such as number of hexagonal network layers, size of the layers, interlayer correlations, interlayer and interatomic distances. The parameters have different effects on the diffraction intensity and the pair distribution function and are verified in reciprocal and real diffraction space simultaneously. The obtained results show that the structure of the glass-like carbons consists of defective graphite-like domains which size increase with the pyrolysis temperature. The heat treatment leads to a noticeable ordering of coherently scattering domains of glass-like carbon in directions perpendicular to graphene-like layers. However, paracrystalline type of disorder within individual layers manifesting itself in decrease in intensity and broadening of the diffraction lines is preserved in the atomic structure even at heat-treatment temperature of 2700°C. © 2016 The American Ceramic Society and Wiley Periodicals, Inc},
note = {6},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This study reports on structural characterization of a series of glass-like carbons obtained by pyrolysis of polyfurfuryl alcohol at 600, 800, 980, and 2700°C. The atomic scale structure of the prepared materials has been studied using wide-angle X-ray scattering technique. The acquired diffraction data were analyzed in reciprocal space as the structure factor and in real space in the form of the pair distribution function to reveal the structural attributes such as number of hexagonal network layers, size of the layers, interlayer correlations, interlayer and interatomic distances. The parameters have different effects on the diffraction intensity and the pair distribution function and are verified in reciprocal and real diffraction space simultaneously. The obtained results show that the structure of the glass-like carbons consists of defective graphite-like domains which size increase with the pyrolysis temperature. The heat treatment leads to a noticeable ordering of coherently scattering domains of glass-like carbon in directions perpendicular to graphene-like layers. However, paracrystalline type of disorder within individual layers manifesting itself in decrease in intensity and broadening of the diffraction lines is preserved in the atomic structure even at heat-treatment temperature of 2700°C. © 2016 The American Ceramic Society and Wiley Periodicals, Inc
2015
Matuszewska, A.; Pusz, S.; Duber, S.
In: International Journal of Coal Geology, vol. 152, pp. 177-188, 2015, ISSN: 01665162, (16).
@article{2-s2.0-84947738363,
title = {Evaluation of the structure of bituminous coal from Sośnica mine in the Upper Silesian Coal Basin (Poland) using reflectance indicating surface (RIS) parameters},
author = { A. Matuszewska and S. Pusz and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84947738363&doi=10.1016%2fj.coal.2015.11.002&partnerID=40&md5=a4b60abc65acef4602bebd9931541e11},
doi = {10.1016/j.coal.2015.11.002},
issn = {01665162},
year = {2015},
date = {2015-01-01},
journal = {International Journal of Coal Geology},
volume = {152},
pages = {177-188},
publisher = {Elsevier},
abstract = {The effect of a magmatic intrusion on the optical properties (reflectance; anisotropy and optical character) of vitrinite in low-rank bituminous coals was examined. The study focused on coal samples collected at different distances from an intrusion emplaced into seam no. 416 in Sośnica mine near Gliwice in the Upper Silesian Coal Basin, Poland. In the immediate contact zone, coal transformed into natural coke may be seen.For comparison, laboratory carbonization of coals weakly changed or apparently unchanged by the intrusion was carried out. The results obtained confirmed that during carbonization of the low-rank coal, heating alone (with no external pressure) makes possible the reorganization of carbon planes that is responsible for the increase of vitrinite reflectance.The heating leads to the destruction of coal-structure cross-linkages (aliphatic groups or heteroatoms) and various further transformations of the structural net, in addition to the removal of volatile carbonization products. External pressures affect the transformation process, especially by promoting the rearrangement of small structural units to form further elements of anisotropic structure. Thus, in the case of coal from the immediate contact of the intrusion, pressures resulted in values of anisotropy parameters higher than those characterizing coal heated in the laboratory up to 1200. °C, but in the absence of stress. The source of pressure that strongly affected the coal in the mine was probably intrusion related. Weak tectonism in the region of the Sośnica mine could explain the fine biaxial optical character of the low rank parent coals more generally. Pressures associated with thermally evolving gasses conceivably led to the growth of structural anisotropy in the walls of degassing pores. Finally, some structural changes seen in coal adjacent to the intrusion may reflect hydrothermal activity. © 2015 Published by Elsevier B.V.},
note = {16},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The effect of a magmatic intrusion on the optical properties (reflectance; anisotropy and optical character) of vitrinite in low-rank bituminous coals was examined. The study focused on coal samples collected at different distances from an intrusion emplaced into seam no. 416 in Sośnica mine near Gliwice in the Upper Silesian Coal Basin, Poland. In the immediate contact zone, coal transformed into natural coke may be seen.For comparison, laboratory carbonization of coals weakly changed or apparently unchanged by the intrusion was carried out. The results obtained confirmed that during carbonization of the low-rank coal, heating alone (with no external pressure) makes possible the reorganization of carbon planes that is responsible for the increase of vitrinite reflectance.The heating leads to the destruction of coal-structure cross-linkages (aliphatic groups or heteroatoms) and various further transformations of the structural net, in addition to the removal of volatile carbonization products. External pressures affect the transformation process, especially by promoting the rearrangement of small structural units to form further elements of anisotropic structure. Thus, in the case of coal from the immediate contact of the intrusion, pressures resulted in values of anisotropy parameters higher than those characterizing coal heated in the laboratory up to 1200. °C, but in the absence of stress. The source of pressure that strongly affected the coal in the mine was probably intrusion related. Weak tectonism in the region of the Sośnica mine could explain the fine biaxial optical character of the low rank parent coals more generally. Pressures associated with thermally evolving gasses conceivably led to the growth of structural anisotropy in the walls of degassing pores. Finally, some structural changes seen in coal adjacent to the intrusion may reflect hydrothermal activity. © 2015 Published by Elsevier B.V.
Smędowski, Ł.; Duber, S.; Matuszewska, A.
An effect of igneous intrusion on the structure, texture and microtexture of coal from the Sośnica coal mine, Upper Silesian Coal Basin, Poland Journal Article
In: Geological Quarterly, vol. 59, no. 3, pp. 507-516, 2015, ISSN: 16417291, (14).
@article{2-s2.0-84944895983,
title = {An effect of igneous intrusion on the structure, texture and microtexture of coal from the Sośnica coal mine, Upper Silesian Coal Basin, Poland},
author = { Ł. Smędowski and S. Duber and A. Matuszewska},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84944895983&doi=10.7306%2fgq.1226&partnerID=40&md5=4fd4a3632184203cffb7fffe509674d9},
doi = {10.7306/gq.1226},
issn = {16417291},
year = {2015},
date = {2015-01-01},
journal = {Geological Quarterly},
volume = {59},
number = {3},
pages = {507-516},
publisher = {Polish Geological Institute},
abstract = {Two coal samples from the Sośnica coal mine, Poland, were analysed in this study. One sample was the natural char collected at the contact of magmatic intrusion, and another sample was the raw coal that was pyrolised in a laboratory furnace. Temperature of pyrolysis was similar to that calculated for the intrusion. The obtained char was analysed to compare its features with those characterizing a natural char sample. Optical microscopy, transmission electron microscopy and Raman spectroscopy studies show that the char from unaltered coal is characterized by the least developed structure, texture and microtexture compared to the natural char. Hence, it can be concluded that geological pressure generated by both the intrusion and the overburden, strongly affects the process of molecular ordering that took place during the heating of coal. The textural, structural or microtextural parameters of coal cannot be used as a geo-thermometer, because they are strongly dependent not only on the temperature but also on other factors. © 2015, Polish Geological Institute. All Rights Reserved.},
note = {14},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Two coal samples from the Sośnica coal mine, Poland, were analysed in this study. One sample was the natural char collected at the contact of magmatic intrusion, and another sample was the raw coal that was pyrolised in a laboratory furnace. Temperature of pyrolysis was similar to that calculated for the intrusion. The obtained char was analysed to compare its features with those characterizing a natural char sample. Optical microscopy, transmission electron microscopy and Raman spectroscopy studies show that the char from unaltered coal is characterized by the least developed structure, texture and microtexture compared to the natural char. Hence, it can be concluded that geological pressure generated by both the intrusion and the overburden, strongly affects the process of molecular ordering that took place during the heating of coal. The textural, structural or microtextural parameters of coal cannot be used as a geo-thermometer, because they are strongly dependent not only on the temperature but also on other factors. © 2015, Polish Geological Institute. All Rights Reserved.
Pawlyta, M.; Rouzaud, J. N.; Duber, S.
Raman microspectroscopy characterization of carbon blacks: Spectral analysis and structural information Journal Article
In: Carbon, vol. 84, no. 1, pp. 479-490, 2015, ISSN: 00086223, (278).
@article{2-s2.0-84922239254,
title = {Raman microspectroscopy characterization of carbon blacks: Spectral analysis and structural information},
author = { M. Pawlyta and J.N. Rouzaud and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84922239254&doi=10.1016%2fj.carbon.2014.12.030&partnerID=40&md5=3e3dbf60270e833a705016125cf4f594},
doi = {10.1016/j.carbon.2014.12.030},
issn = {00086223},
year = {2015},
date = {2015-01-01},
journal = {Carbon},
volume = {84},
number = {1},
pages = {479-490},
publisher = {Elsevier Ltd},
abstract = {The aim of this paper is to describe carbonisation and partial graphitization of carbon blacks (CB). Raman spectrometry is used to investigate a series of five CB grades during heat treatment (up to 2600 °C). Obtained results are discussed by comparing Raman data with X-ray diffraction and high-resolution transmission electron microscopy (HRTEM) observations. For Raman spectra interpretation, the usual curve fitting method proposed by Sadezky et al. for soot and disordered carbonaceous material is applied. As the same procedure can be applied over all the heat-treatment temperature range, the determination of band parameters from five band decompositions appears to be the most convenient to follow the CB's structural improvement. We demonstrate that only a partial graphitization takes place and the graphitizability is limited by the diameter of the primary particles. Our observations generalize the results obtained for cokes: graphitization degree of carbonaceous materials after the heat-treatment is limited by the diameter of the volumes within polyaromatic layers are oriented in parallel. © 2014 Elsevier Ltd. All rights reserved.},
note = {278},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The aim of this paper is to describe carbonisation and partial graphitization of carbon blacks (CB). Raman spectrometry is used to investigate a series of five CB grades during heat treatment (up to 2600 °C). Obtained results are discussed by comparing Raman data with X-ray diffraction and high-resolution transmission electron microscopy (HRTEM) observations. For Raman spectra interpretation, the usual curve fitting method proposed by Sadezky et al. for soot and disordered carbonaceous material is applied. As the same procedure can be applied over all the heat-treatment temperature range, the determination of band parameters from five band decompositions appears to be the most convenient to follow the CB's structural improvement. We demonstrate that only a partial graphitization takes place and the graphitizability is limited by the diameter of the primary particles. Our observations generalize the results obtained for cokes: graphitization degree of carbonaceous materials after the heat-treatment is limited by the diameter of the volumes within polyaromatic layers are oriented in parallel. © 2014 Elsevier Ltd. All rights reserved.
2014
Pusz, S.; Borrego, A. G.; Alvarez, D.; Camean, I.; du Cann, V.; Duber, S.; Kalkreuth, W.; Komorek, J.; Kus, J.; Kwiecińska, B.; Libera, M.; Marques, M. M.; Misz-Kennan, M.; Morga, R.; Rodrigues, S.; Smędowski, Ł.; Suárez-Ruiz, I.; Strzezik, J.
In: International Journal of Coal Geology, vol. 131, pp. 147-161, 2014, ISSN: 01665162, (20).
@article{2-s2.0-84903433684,
title = {Application of reflectance parameters in the estimation of the structural order of coals and carbonaceous materials. Precision and bias of measurements derived from the ICCP structural working group},
author = { S. Pusz and A.G. Borrego and D. Alvarez and I. Camean and V. du Cann and S. Duber and W. Kalkreuth and J. Komorek and J. Kus and B. Kwiecińska and M. Libera and M.M. Marques and M. Misz-Kennan and R. Morga and S. Rodrigues and Ł. Smędowski and I. Suárez-Ruiz and J. Strzezik},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84903433684&doi=10.1016%2fj.coal.2014.04.004&partnerID=40&md5=fa55994ed4a58ff3507f5b0cb04a2bad},
doi = {10.1016/j.coal.2014.04.004},
issn = {01665162},
year = {2014},
date = {2014-01-01},
journal = {International Journal of Coal Geology},
volume = {131},
pages = {147-161},
publisher = {Elsevier},
abstract = {Optical reflectance of vitrinite is one of the fundamental physical properties that have been used for the study of coal and carbonaceous materials. Organic matter in coals and carbonaceous matter consists mainly of aromatic lamellae, whose dimensions and spatial orientation define its internal structure. Various reflectance parameters describe well the average degree of order of the molecular structure of organic matter. Moreover, reflectance parameters are numerical values which characterize the samples unambiguously, facilitating the comparison of the optical properties of different carbonaceous materials as well as comparison between optical parameters and other physical or chemical factors. The focus of this study is the evaluation of the precision and bias of reflectance measurements (Rmax and Rmin) performed by various analysts in different laboratories in order to check the applicability of reflectance parameters to the estimation of the structural order of coals and carbonaceous materials. Additionally, it was desirable to compare reflectance parameters with other parameters obtained by different analytical methods able to provide structural information. The consistency and repeatability of the reflectance measurements obtained by different participants turned out to enable the drawing of similar conclusions regarding the structural transformation of anthracite during heating. Good correlations were found between the reflectance parameters studied and structural factors obtained by comparative methods. The reflectance parameters examined proved to be very sensitive to any changes of the structural order of coals and carbonaceous materials and seem to be a perfect complement to structural studies made by X-ray diffraction or Raman spectroscopy. © 2014.},
note = {20},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Optical reflectance of vitrinite is one of the fundamental physical properties that have been used for the study of coal and carbonaceous materials. Organic matter in coals and carbonaceous matter consists mainly of aromatic lamellae, whose dimensions and spatial orientation define its internal structure. Various reflectance parameters describe well the average degree of order of the molecular structure of organic matter. Moreover, reflectance parameters are numerical values which characterize the samples unambiguously, facilitating the comparison of the optical properties of different carbonaceous materials as well as comparison between optical parameters and other physical or chemical factors. The focus of this study is the evaluation of the precision and bias of reflectance measurements (Rmax and Rmin) performed by various analysts in different laboratories in order to check the applicability of reflectance parameters to the estimation of the structural order of coals and carbonaceous materials. Additionally, it was desirable to compare reflectance parameters with other parameters obtained by different analytical methods able to provide structural information. The consistency and repeatability of the reflectance measurements obtained by different participants turned out to enable the drawing of similar conclusions regarding the structural transformation of anthracite during heating. Good correlations were found between the reflectance parameters studied and structural factors obtained by comparative methods. The reflectance parameters examined proved to be very sensitive to any changes of the structural order of coals and carbonaceous materials and seem to be a perfect complement to structural studies made by X-ray diffraction or Raman spectroscopy. © 2014.
2013
Łoś, S.; Duclaux, L.; Alvarez, L.; Hawełek, Ł.; Duber, S.; Kempiński, W.
Cleavage and size reduction of graphite crystal using ultrasound radiation Journal Article
In: Carbon, vol. 55, pp. 53-61, 2013, ISSN: 00086223, (32).
@article{2-s2.0-84873406287,
title = {Cleavage and size reduction of graphite crystal using ultrasound radiation},
author = { S. Łoś and L. Duclaux and L. Alvarez and Ł. Hawełek and S. Duber and W. Kempiński},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84873406287&doi=10.1016%2fj.carbon.2012.12.005&partnerID=40&md5=419bee0d3049de8e4d8e54261fa4437f},
doi = {10.1016/j.carbon.2012.12.005},
issn = {00086223},
year = {2013},
date = {2013-01-01},
journal = {Carbon},
volume = {55},
pages = {53-61},
abstract = {The influence of ultrasound radiation on graphite structure was studied by laser light scattering, X-ray diffraction, Raman spectroscopy and Transmission Electron Microscopy. Irradiations of polycrystalline graphite powder suspensions at frequencies of 20 kHz and 500 kHz, were carried out in three different solvents: water (as the best medium for cavitation), a surfactant (OMImBr) aqueous solution and also a mixture of sulfuric and nitric acids which caused the exfoliation by intercalation. The average basal particle size of 168 μm was reduced to 4 μm after ultrasonication delivering a huge energy density up to 1.2 MW/m2. Change of the sonication time and the nature of the solvents produced different reduction of the graphite crystals dimensions, affecting the out of plane thickness and the basal width as well. The ultrasonication promoted the disordering of the graphite tridimensional stacking for all solvents used, with the strongest effect in acidic medium. Turbostratic structures formation and exfoliation of graphene flakes have been observed after the use of surfactant for sonication medium. Intercalation in acid medium prior to the ultrasound treatment produced similar effects. © 2012 Elsevier Ltd. All rights reserved.},
note = {32},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The influence of ultrasound radiation on graphite structure was studied by laser light scattering, X-ray diffraction, Raman spectroscopy and Transmission Electron Microscopy. Irradiations of polycrystalline graphite powder suspensions at frequencies of 20 kHz and 500 kHz, were carried out in three different solvents: water (as the best medium for cavitation), a surfactant (OMImBr) aqueous solution and also a mixture of sulfuric and nitric acids which caused the exfoliation by intercalation. The average basal particle size of 168 μm was reduced to 4 μm after ultrasonication delivering a huge energy density up to 1.2 MW/m2. Change of the sonication time and the nature of the solvents produced different reduction of the graphite crystals dimensions, affecting the out of plane thickness and the basal width as well. The ultrasonication promoted the disordering of the graphite tridimensional stacking for all solvents used, with the strongest effect in acidic medium. Turbostratic structures formation and exfoliation of graphene flakes have been observed after the use of surfactant for sonication medium. Intercalation in acid medium prior to the ultrasound treatment produced similar effects. © 2012 Elsevier Ltd. All rights reserved.
2009
Quirico, E.; Montagnac, G.; Rouzaud, J. N.; Bonal, L.; Bourot-Denise, M.; Duber, S.; Reynard, B.
Precursor and metamorphic condition effects on Raman spectra of poorly ordered carbonaceous matter in chondrites and coals Journal Article
In: Earth and Planetary Science Letters, vol. 287, no. 1-2, pp. 185-193, 2009, ISSN: 0012821X, (105).
@article{2-s2.0-70349385145,
title = {Precursor and metamorphic condition effects on Raman spectra of poorly ordered carbonaceous matter in chondrites and coals},
author = { E. Quirico and G. Montagnac and J.N. Rouzaud and L. Bonal and M. Bourot-Denise and S. Duber and B. Reynard},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-70349385145&doi=10.1016%2fj.epsl.2009.07.041&partnerID=40&md5=3da55b21edb79281c92b54d8736d3cce},
doi = {10.1016/j.epsl.2009.07.041},
issn = {0012821X},
year = {2009},
date = {2009-01-01},
journal = {Earth and Planetary Science Letters},
volume = {287},
number = {1-2},
pages = {185-193},
publisher = {Elsevier B.V.},
abstract = {Geothermometers based on Raman spectrometry of carbonaceous matter and covering a wide range of temperatures (100-650 °C) have been developed over recent years. While Raman data have been largely interpreted in terms of temperature, they are also the fingerprint of certain metamorphic conditions, especially in the low temperature range relevant to poorly ordered carbonaceous matter. This study investigates the Raman spectra of two series of chondritic carbonaceous matter and coal samples formed from different precursors and under different metamorphic conditions. The Raman spectra of Polyaromatic Carbonaceous Matter (PCM) from 42 chondrites and 27 coal samples, measured with visible (514 nm) and ultra-violet (244 nm) excitation wavelengths, are analyzed. The Raman spectra of low rank coals and chondrites of petrologic types 1 and 2, which contain the more disordered PCM, reflect the distinct carbon structures of their precursors. The 514 nm Raman spectra of high rank coals and chondrites of petrologic type 3 exhibit continuous and systematic spectral differences reflecting different carbon structures present during the metamorphism event. They result from differences in the chemical structures of the precursors concerning for instance the reticulation of polyaromatic units or an abundance of ether functional groups, or possibly from a lack of carbonization processes to efficiently expel oxygen heteroatoms, due to weak lithostatic pressure and confinement. These results suggest that the use of low temperature carbon thermometers should be restricted to a given geological context. At the same time, the sensitivity of Raman spectra to precursors and certain metamorphic conditions could be used to obtain information other than temperature. The analysis also provides evidence of the accretion of relatively homogeneous PCM precursors among ordinary CO and CV carbonaceous chondrite parent bodies, given that the 514 nm Raman spectra of PCM efficiently trace the metamorphism grades. Looking closer, however, the 514 nm Raman data are more scattered in chondrites than in coals and the maturity tracers are less sensitive and miscorrelate with the atomic H/C ratio, suggesting slight compositional and structural differences among the PCM precursors accreted. © 2009 Elsevier B.V. All rights reserved.},
note = {105},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Geothermometers based on Raman spectrometry of carbonaceous matter and covering a wide range of temperatures (100-650 °C) have been developed over recent years. While Raman data have been largely interpreted in terms of temperature, they are also the fingerprint of certain metamorphic conditions, especially in the low temperature range relevant to poorly ordered carbonaceous matter. This study investigates the Raman spectra of two series of chondritic carbonaceous matter and coal samples formed from different precursors and under different metamorphic conditions. The Raman spectra of Polyaromatic Carbonaceous Matter (PCM) from 42 chondrites and 27 coal samples, measured with visible (514 nm) and ultra-violet (244 nm) excitation wavelengths, are analyzed. The Raman spectra of low rank coals and chondrites of petrologic types 1 and 2, which contain the more disordered PCM, reflect the distinct carbon structures of their precursors. The 514 nm Raman spectra of high rank coals and chondrites of petrologic type 3 exhibit continuous and systematic spectral differences reflecting different carbon structures present during the metamorphism event. They result from differences in the chemical structures of the precursors concerning for instance the reticulation of polyaromatic units or an abundance of ether functional groups, or possibly from a lack of carbonization processes to efficiently expel oxygen heteroatoms, due to weak lithostatic pressure and confinement. These results suggest that the use of low temperature carbon thermometers should be restricted to a given geological context. At the same time, the sensitivity of Raman spectra to precursors and certain metamorphic conditions could be used to obtain information other than temperature. The analysis also provides evidence of the accretion of relatively homogeneous PCM precursors among ordinary CO and CV carbonaceous chondrite parent bodies, given that the 514 nm Raman spectra of PCM efficiently trace the metamorphism grades. Looking closer, however, the 514 nm Raman data are more scattered in chondrites than in coals and the maturity tracers are less sensitive and miscorrelate with the atomic H/C ratio, suggesting slight compositional and structural differences among the PCM precursors accreted. © 2009 Elsevier B.V. All rights reserved.
Smieja-Król, B.; Duber, S.; Rouzaud, J. N.
Multiscale organisation of organic matter associated with gold and uranium minerals in the Witwatersrand basin, South Africa Journal Article
In: International Journal of Coal Geology, vol. 78, no. 1, pp. 77-88, 2009, ISSN: 01665162, (20).
@article{2-s2.0-59649101053,
title = {Multiscale organisation of organic matter associated with gold and uranium minerals in the Witwatersrand basin, South Africa},
author = { B. Smieja-Król and S. Duber and J.N. Rouzaud},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-59649101053&doi=10.1016%2fj.coal.2008.09.007&partnerID=40&md5=ff220fc3eb6385aa8a3998a1ff52d200},
doi = {10.1016/j.coal.2008.09.007},
issn = {01665162},
year = {2009},
date = {2009-01-01},
journal = {International Journal of Coal Geology},
volume = {78},
number = {1},
pages = {77-88},
publisher = {Elsevier B.V.},
abstract = {Organic matter from the northern part of the Early Proterozoic Witwatersrand basin (Carbon Leader reef) was investigated using optical (OM) and transmission electron (TEM) microscopes, completed by XRD analysis. The multiscale organization (texture; microtexture; structure) of the organic matter was observed in order to gain information about the processes which affected organic material after its deposition in sediments. In the micrometre scale (optical microscope), the shape and size of the Reflectance Indicating Surface (RIS) of the organic matter were determined. The organic matter reveals a prevailing biaxial symmetry. The size of RIS is generally dependent on uranium and increases with increasing uranium concentration. Furthermore, it appears that more than one RIS is present within the scale of a single sample, each with a different symmetry and size. The presence of domains differing in organisation of the aromatic framework was confirmed by TEM observation in the DF mode. The aromatic skeleton of organic matter is composed of short, often crumpled, mostly isolated (non-stacked) polyaromatic layers whose fringe length corresponds to 3-16 aromatic rings. The data indicate reorganization of the polyaromatic organic matter structure under stress in high pressure and relatively low temperature conditions. The organic matter was in a solid state within the rocks before the pressure event. © 2008 Elsevier B.V. All rights reserved.},
note = {20},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Organic matter from the northern part of the Early Proterozoic Witwatersrand basin (Carbon Leader reef) was investigated using optical (OM) and transmission electron (TEM) microscopes, completed by XRD analysis. The multiscale organization (texture; microtexture; structure) of the organic matter was observed in order to gain information about the processes which affected organic material after its deposition in sediments. In the micrometre scale (optical microscope), the shape and size of the Reflectance Indicating Surface (RIS) of the organic matter were determined. The organic matter reveals a prevailing biaxial symmetry. The size of RIS is generally dependent on uranium and increases with increasing uranium concentration. Furthermore, it appears that more than one RIS is present within the scale of a single sample, each with a different symmetry and size. The presence of domains differing in organisation of the aromatic framework was confirmed by TEM observation in the DF mode. The aromatic skeleton of organic matter is composed of short, often crumpled, mostly isolated (non-stacked) polyaromatic layers whose fringe length corresponds to 3-16 aromatic rings. The data indicate reorganization of the polyaromatic organic matter structure under stress in high pressure and relatively low temperature conditions. The organic matter was in a solid state within the rocks before the pressure event. © 2008 Elsevier B.V. All rights reserved.
2006
Pentak, D.; Sułkowski, W. W.; Maślanka, S.; Wolińska, A.; Duber, S.; Sułkowska, A.
Characteristics of liposomes prepared by the modified reverse-phase evaporation method:31P-NMR and TEM study Proceedings
vol. 245-246, 2006, ISSN: 10221360, (5).
@proceedings{2-s2.0-33947130354,
title = {Characteristics of liposomes prepared by the modified reverse-phase evaporation method:31P-NMR and TEM study},
author = { D. Pentak and W.W. Sułkowski and S. Maślanka and A. Wolińska and S. Duber and A. Sułkowska},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33947130354&doi=10.1002%2fmasy.200651368&partnerID=40&md5=8b0faad0e84addeda2bc18517091df69},
doi = {10.1002/masy.200651368},
issn = {10221360},
year = {2006},
date = {2006-01-01},
journal = {Macromolecular Symposia},
volume = {245-246},
pages = {476-484},
abstract = {The NMR spectroscopy was used to determine a structure and physicochemical properties of liposomes prepared from L-α-phosphatidylcholine dipalmitoyl (DPPC) by the modified reverse-phase evaporation method (mREV). 31P-NMR study of the liposome in the temperature range from 340K to 350K allowed us to suggest that the single-bilayered liposome has been obtained. Transmission electron micrographs (TEM) showed that the liposome vesicles, obtained with the use of the modified (mREV) method, were spherical in shape and in majority they were less than 100 nm in diameter. Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA.},
note = {5},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
The NMR spectroscopy was used to determine a structure and physicochemical properties of liposomes prepared from L-α-phosphatidylcholine dipalmitoyl (DPPC) by the modified reverse-phase evaporation method (mREV). 31P-NMR study of the liposome in the temperature range from 340K to 350K allowed us to suggest that the single-bilayered liposome has been obtained. Transmission electron micrographs (TEM) showed that the liposome vesicles, obtained with the use of the modified (mREV) method, were spherical in shape and in majority they were less than 100 nm in diameter. Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA.
Gauden, P. A.; Szmechtig-Gauden, E.; Rychlicki, G.; Duber, S.; Garbacz, J. K.; Buczkowski, R.
Changes of the porous structure of activated carbons applied in a filter bed pilot operation Journal Article
In: Journal of Colloid and Interface Science, vol. 295, no. 2, pp. 327-347, 2006, ISSN: 00219797, (19).
@article{2-s2.0-32544445858,
title = {Changes of the porous structure of activated carbons applied in a filter bed pilot operation},
author = { P.A. Gauden and E. Szmechtig-Gauden and G. Rychlicki and S. Duber and J.K. Garbacz and R. Buczkowski},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-32544445858&doi=10.1016%2fj.jcis.2005.08.039&partnerID=40&md5=e73136a1d686aaa1c8238038a396df65},
doi = {10.1016/j.jcis.2005.08.039},
issn = {00219797},
year = {2006},
date = {2006-01-01},
journal = {Journal of Colloid and Interface Science},
volume = {295},
number = {2},
pages = {327-347},
abstract = {The paper investigates the changes in porosity (i.e.; in the accessible adsorption capacity of carbonaceous adsorbents for pollutants during filter bed maturation) of three activated carbons applied in a filter bed pilot operation. The results of this investigation may help to reduce operating costs, increase granular activated carbon bed life, maximize the useful life of biofilters, and understand the mechanism of water purification by carbon adsorbents. The analysis of the pore structure was limited to the first year of service of the beds, since this was when the largest decrease in the available pore capacity occurred. Low-temperature nitrogen adsorption isotherms were used to evaluate the structural parameters and pore size distributions (PSDs) of carbon samples (virgin (reference) and mature adsorbents for different periods of water treatment) on the basis of the Nguyen and Do (ND) method and density functional theory (DFT). These results were compared with small-angle X-ray scattering (SAXS) investigations (PSDs calculated by Glatter's indirect transformation method (ITP)). The results show that in general, the ND and ITP methods lead to almost the same qualitative distribution curve behavior. Moreover, the enthalpy of immersion in water, mercury porosimetry, densities (true and apparent), and the analysis of ash are reported and compared to explain the decrease in adsorptive capacity of the carbons investigated. On the other hand, the efficacy of TOC (total organic carbon; i.e.; a quantity describing the complex matrix of organic material present in natural waters) removal and the bacteria count were analyzed to explain the role of adsorption in the elimination of contaminants from water. Finally, a mechanism of organic matter removal was suggested on the basis of the above-mentioned experimental data and compared with mechanisms reported by other authors. © 2005 Elsevier Inc. All rights reserved.},
note = {19},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The paper investigates the changes in porosity (i.e.; in the accessible adsorption capacity of carbonaceous adsorbents for pollutants during filter bed maturation) of three activated carbons applied in a filter bed pilot operation. The results of this investigation may help to reduce operating costs, increase granular activated carbon bed life, maximize the useful life of biofilters, and understand the mechanism of water purification by carbon adsorbents. The analysis of the pore structure was limited to the first year of service of the beds, since this was when the largest decrease in the available pore capacity occurred. Low-temperature nitrogen adsorption isotherms were used to evaluate the structural parameters and pore size distributions (PSDs) of carbon samples (virgin (reference) and mature adsorbents for different periods of water treatment) on the basis of the Nguyen and Do (ND) method and density functional theory (DFT). These results were compared with small-angle X-ray scattering (SAXS) investigations (PSDs calculated by Glatter's indirect transformation method (ITP)). The results show that in general, the ND and ITP methods lead to almost the same qualitative distribution curve behavior. Moreover, the enthalpy of immersion in water, mercury porosimetry, densities (true and apparent), and the analysis of ash are reported and compared to explain the decrease in adsorptive capacity of the carbons investigated. On the other hand, the efficacy of TOC (total organic carbon; i.e.; a quantity describing the complex matrix of organic material present in natural waters) removal and the bacteria count were analyzed to explain the role of adsorption in the elimination of contaminants from water. Finally, a mechanism of organic matter removal was suggested on the basis of the above-mentioned experimental data and compared with mechanisms reported by other authors. © 2005 Elsevier Inc. All rights reserved.
2004
Cebulak, S.; Smieja-Król, B.; Duber, S.; Misz-Kennan, M.; Morawski, A. W.
Oxyreactive thermal analysis a good tool for the investigation of carbon materials Proceedings
vol. 77, no. 1, 2004, ISSN: 13886150, (4).
@proceedings{2-s2.0-3142687648,
title = {Oxyreactive thermal analysis a good tool for the investigation of carbon materials},
author = { S. Cebulak and B. Smieja-Król and S. Duber and M. Misz-Kennan and A.W. Morawski},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-3142687648&doi=10.1023%2fB%3aJTAN.0000033204.53768.bb&partnerID=40&md5=9e47000f57697d526c32ad4a2843863f},
doi = {10.1023/B:JTAN.0000033204.53768.bb},
issn = {13886150},
year = {2004},
date = {2004-01-01},
journal = {Journal of Thermal Analysis and Calorimetry},
volume = {77},
number = {1},
pages = {201-206},
abstract = {The paper presents the applicability of Oxyreactive Thermal Analysis (OTA) for the investigation of different kinds of carbon matter. For comparative reasons and more precise interpretation, along with OTA some physico-chemical properties of analyzed materials were used as the methods commonly applied for the investigations. The carbon materials of both natural (anthracites; graphite and diamonds) and synthetic origin (active carbon; glass carbon; expanded graphite; soot and synthetic diamonds) were investigated. It was stated that there is close relationship between structure parameters and physico-chemical properties and the thermal reactivity within the investigated groups of carbon matters. The results show that OTA can be accepted as a good investigative way for such materials.},
note = {4},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
The paper presents the applicability of Oxyreactive Thermal Analysis (OTA) for the investigation of different kinds of carbon matter. For comparative reasons and more precise interpretation, along with OTA some physico-chemical properties of analyzed materials were used as the methods commonly applied for the investigations. The carbon materials of both natural (anthracites; graphite and diamonds) and synthetic origin (active carbon; glass carbon; expanded graphite; soot and synthetic diamonds) were investigated. It was stated that there is close relationship between structure parameters and physico-chemical properties and the thermal reactivity within the investigated groups of carbon matters. The results show that OTA can be accepted as a good investigative way for such materials.
Szczygielska, A.; Burian, A.; Dore, J. C.; Honkimäki, V.; Duber, S.
vol. 362, no. 1-2, 2004, ISSN: 09258388, (13).
@proceedings{2-s2.0-0344466343,
title = {Local structure of saccharose- and anthracene-based carbons studied by wide-angle high-energy X-ray scattering},
author = { A. Szczygielska and A. Burian and J.C. Dore and V. Honkimäki and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0344466343&doi=10.1016%2fS0925-8388%2803%2900604-2&partnerID=40&md5=c4dcd5d9675b98bacf0e354f080c7e56},
doi = {10.1016/S0925-8388(03)00604-2},
issn = {09258388},
year = {2004},
date = {2004-01-01},
journal = {Journal of Alloys and Compounds},
volume = {362},
number = {1-2},
pages = {307-313},
abstract = {A series of porous carbon materials, produced by pyrolysis of saccharose and anthracene and heat treated at 1000, 1900 and 2300°C have been studied by wide-angle X-ray scattering. The X-ray data were collected at European Synchrotron Radiation Facility (ESRF) in Grenoble on the ID15A beam line (high-energy X-ray diffraction) using a wavelength of E = 116.2 keV, λ = 0.1067 Å. The data were recorded in the scattering vector range from 0.5 to 24 Å-1 which enabled them be converted to a real-space representation via the Fourier transform. The structure of these carbons has been described in terms of a model based on disordered, graphite-like layers with very weak interlayer correlations. At higher temperatures the anthracene-based carbon transforms into graphite while the carbon produced from saccharose remains disordered. The graphitization process has been studied in detail by careful analysis of the diffraction data in real and reciprocal space. © 2003 Elsevier B.V. All rights reserved.},
note = {13},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
A series of porous carbon materials, produced by pyrolysis of saccharose and anthracene and heat treated at 1000, 1900 and 2300°C have been studied by wide-angle X-ray scattering. The X-ray data were collected at European Synchrotron Radiation Facility (ESRF) in Grenoble on the ID15A beam line (high-energy X-ray diffraction) using a wavelength of E = 116.2 keV, λ = 0.1067 Å. The data were recorded in the scattering vector range from 0.5 to 24 Å-1 which enabled them be converted to a real-space representation via the Fourier transform. The structure of these carbons has been described in terms of a model based on disordered, graphite-like layers with very weak interlayer correlations. At higher temperatures the anthracene-based carbon transforms into graphite while the carbon produced from saccharose remains disordered. The graphitization process has been studied in detail by careful analysis of the diffraction data in real and reciprocal space. © 2003 Elsevier B.V. All rights reserved.
2003
Pusz, S.; Kwiecińska, B.; Duber, S.
Textural transformation of thermally treated anthracites Journal Article
In: International Journal of Coal Geology, vol. 54, no. 1-2, pp. 115-123, 2003, ISSN: 01665162, (32).
@article{2-s2.0-0038370184,
title = {Textural transformation of thermally treated anthracites},
author = { S. Pusz and B. Kwiecińska and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0038370184&doi=10.1016%2fS0166-5162%2803%2900024-7&partnerID=40&md5=0edf771866f613575a4e60000b8cee9d},
doi = {10.1016/S0166-5162(03)00024-7},
issn = {01665162},
year = {2003},
date = {2003-01-01},
journal = {International Journal of Coal Geology},
volume = {54},
number = {1-2},
pages = {115-123},
publisher = {Elsevier B.V.},
abstract = {The organic matter of anthracites consists of turbostratic (two-dimensional crystalline order) stacks of three to five aromatic layers called the Basic Structural Units (BSU). The arrangement of BSU forms the texture of anthracites, which corresponds to their chemical and physical properties including optical properties (reflectance values). Thermal treatment leads to the changes in the arrangement of BSU. The character of structural and textural transformation of anthracites during heating can be determined based on the changes of reflectance values of anthracites. Several anthracites of various ranks were thermally treated over the temperature range of 400 (673 K)-1000 °C (1273 K) in an inert atmosphere (N2), at atmospheric pressure. The reflectance indicating surfaces (RIS) were reconstructed and reflectance indicatrix parameters were calculated according to the Kilby method specially modified for the study of anthracites. It was found that the relative increase of reflectance values (Rmax, Rmin) was greater for the lower metamorphosed samples than for the higher ones. However, the higher rank of initial samples, the greater their final reflectance values and the anisotropy of the texture attained at 1000 °C. It indicates that the texture of the higher metamorphosed anthracites (meta-anthracites) is more flexible for rearrangement during heating, than the texture of the lower metamorphosed anthracites. Moreover, the difference in the changes of reflectance values versus temperature for the higher and for the lower rank anthracites suggests that meta-anthracites have undergone stronger natural metamorphism equivalent to about 200 °C in comparison with the other anthracites. It could be said that the character of textural transformations of individual anthracites results from the degree of their metamorphism and, in a consequence, from the texture of parent sediments. © 2003 Elsevier Science B.V. All rights reserved.},
note = {32},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The organic matter of anthracites consists of turbostratic (two-dimensional crystalline order) stacks of three to five aromatic layers called the Basic Structural Units (BSU). The arrangement of BSU forms the texture of anthracites, which corresponds to their chemical and physical properties including optical properties (reflectance values). Thermal treatment leads to the changes in the arrangement of BSU. The character of structural and textural transformation of anthracites during heating can be determined based on the changes of reflectance values of anthracites. Several anthracites of various ranks were thermally treated over the temperature range of 400 (673 K)-1000 °C (1273 K) in an inert atmosphere (N2), at atmospheric pressure. The reflectance indicating surfaces (RIS) were reconstructed and reflectance indicatrix parameters were calculated according to the Kilby method specially modified for the study of anthracites. It was found that the relative increase of reflectance values (Rmax, Rmin) was greater for the lower metamorphosed samples than for the higher ones. However, the higher rank of initial samples, the greater their final reflectance values and the anisotropy of the texture attained at 1000 °C. It indicates that the texture of the higher metamorphosed anthracites (meta-anthracites) is more flexible for rearrangement during heating, than the texture of the lower metamorphosed anthracites. Moreover, the difference in the changes of reflectance values versus temperature for the higher and for the lower rank anthracites suggests that meta-anthracites have undergone stronger natural metamorphism equivalent to about 200 °C in comparison with the other anthracites. It could be said that the character of textural transformations of individual anthracites results from the degree of their metamorphism and, in a consequence, from the texture of parent sediments. © 2003 Elsevier Science B.V. All rights reserved.
2002
Szczygielska, A.; Burian, A.; Dore, J. C.; Duber, S.; Hannon, A.
Paracrystalline nature of saccharose and anthracene-based carbons studied by wide-angle scattering Proceedings
vol. 5136, 2002, ISSN: 0277786X.
@proceedings{2-s2.0-1342311391,
title = {Paracrystalline nature of saccharose and anthracene-based carbons studied by wide-angle scattering},
author = { A. Szczygielska and A. Burian and J.C. Dore and S. Duber and A. Hannon},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-1342311391&partnerID=40&md5=970300bddc87548828bea4499323942b},
issn = {0277786X},
year = {2002},
date = {2002-01-01},
journal = {Proceedings of SPIE - The International Society for Optical Engineering},
volume = {5136},
pages = {288-294},
abstract = {A series of porous carbon materials, produced by pyrolysis of saccharose and anthracene and heat treated at 1000°C, 1800°C and 2600°C has been studied by wide-angle neutron scattering. The neutron data were collected at Rutheford Appleton Laboratory (RAL). The data were recorded in the scattering vector range from 0 to 60 Å-1 which enabled them to be converted to a real-space representation via the Fourier transform. The structure of these carbons has been described in terms of a model based on disordered, graphite-like layers with very weak interlayer correlations. At higher temperatures the anthracene-based carbon transforms into graphite while the carbon produced from saccharose remains disordered. The graphitization process has been studied in detail by careful analysis of the diffraction data in real and reciprocal space.},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
A series of porous carbon materials, produced by pyrolysis of saccharose and anthracene and heat treated at 1000°C, 1800°C and 2600°C has been studied by wide-angle neutron scattering. The neutron data were collected at Rutheford Appleton Laboratory (RAL). The data were recorded in the scattering vector range from 0 to 60 Å-1 which enabled them to be converted to a real-space representation via the Fourier transform. The structure of these carbons has been described in terms of a model based on disordered, graphite-like layers with very weak interlayer correlations. At higher temperatures the anthracene-based carbon transforms into graphite while the carbon produced from saccharose remains disordered. The graphitization process has been studied in detail by careful analysis of the diffraction data in real and reciprocal space.
Kwiecińska, B.; Pusz, S.; Duber, S.
Petrographical study of anthracites from European coal basins Journal Article
In: Polish Geological Institute Special Papers, vol. 7, pp. 149-158, 2002, ISSN: 15079791, (1).
@article{2-s2.0-0036994357,
title = {Petrographical study of anthracites from European coal basins},
author = { B. Kwiecińska and S. Pusz and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0036994357&partnerID=40&md5=cffc105c7fef40830b132d4b921caead},
issn = {15079791},
year = {2002},
date = {2002-01-01},
journal = {Polish Geological Institute Special Papers},
volume = {7},
pages = {149-158},
abstract = {The anthracites from several coal basins occurring in France, Germany, Ireland, Poland, Romania, Russia, Ukraine and United Kingdom were studied in reflected plane-polarised light (Olympus microscope). Three maceral groups (vitrinite, inertinite, liptinite) and associated mineral matter were distinguished. All the anthracites are dominantly composed of vitrinite (75-95%), inertinite is minor (2.5-19%), and liptinite is very rare (up to 1.5%, with one exception - 4.4%). In vitrinite group, the following macerals: collotelinite, telinite, collodetrinite, vitrodetrinite, and pseudovitrinite were recognised. In inertinite group, the most abundant are fusinite and semifusinite. Liptinite in general is dominated by sporinite. In some anthracites, liptinite was not accounted at all, perhaps, in such highly metamorphosed anthracites, sporinite underwent a rapid change in chemical and physical composition, and became optically indistinguishable from vitrinite. In a few samples, sporinite can be recognised from its vitrinite matrix by a distinct optical morphology. Optical microscopical studies of all anthracites revealed significant heterogeneity of the samples, clearly visible under crossed nicols with the use of higher magnifications. This heterogeneity reflects the differences in coal facies, in primary maceral composition, inherited from peat or sub-bituminous stages but also in strain or pressure being distributed inhomogeneously during formation of anthracite. In all cases, heterogeneous microtexture (fine, coarse, granular, mosaic, and fibrous) was observed. Porous and lamellar particles coexist very often together. Coke-like structure, with numerous devolatilization vacuoles, was also recognised. Pyrolytic carbon occuring as veins, sub-parallel to bedding, can be easily noticed in some samples. Pyrolytic carbon types are presumed to originate from volatiles evolved during condensation reactions. Reflectance values (Rmax) of anthracites vary from 2.3% up to 8.9%. These samples which exhibit Rmax higher than 6% were considered as meta-anthracites. It seems, that the latter are made of conglomerates of graphite-like complexes having preferential planar orientation and structurally less organised compounds with typical turbostratic arrangement of the aromatic units.},
note = {1},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The anthracites from several coal basins occurring in France, Germany, Ireland, Poland, Romania, Russia, Ukraine and United Kingdom were studied in reflected plane-polarised light (Olympus microscope). Three maceral groups (vitrinite, inertinite, liptinite) and associated mineral matter were distinguished. All the anthracites are dominantly composed of vitrinite (75-95%), inertinite is minor (2.5-19%), and liptinite is very rare (up to 1.5%, with one exception - 4.4%). In vitrinite group, the following macerals: collotelinite, telinite, collodetrinite, vitrodetrinite, and pseudovitrinite were recognised. In inertinite group, the most abundant are fusinite and semifusinite. Liptinite in general is dominated by sporinite. In some anthracites, liptinite was not accounted at all, perhaps, in such highly metamorphosed anthracites, sporinite underwent a rapid change in chemical and physical composition, and became optically indistinguishable from vitrinite. In a few samples, sporinite can be recognised from its vitrinite matrix by a distinct optical morphology. Optical microscopical studies of all anthracites revealed significant heterogeneity of the samples, clearly visible under crossed nicols with the use of higher magnifications. This heterogeneity reflects the differences in coal facies, in primary maceral composition, inherited from peat or sub-bituminous stages but also in strain or pressure being distributed inhomogeneously during formation of anthracite. In all cases, heterogeneous microtexture (fine, coarse, granular, mosaic, and fibrous) was observed. Porous and lamellar particles coexist very often together. Coke-like structure, with numerous devolatilization vacuoles, was also recognised. Pyrolytic carbon occuring as veins, sub-parallel to bedding, can be easily noticed in some samples. Pyrolytic carbon types are presumed to originate from volatiles evolved during condensation reactions. Reflectance values (Rmax) of anthracites vary from 2.3% up to 8.9%. These samples which exhibit Rmax higher than 6% were considered as meta-anthracites. It seems, that the latter are made of conglomerates of graphite-like complexes having preferential planar orientation and structurally less organised compounds with typical turbostratic arrangement of the aromatic units.
Pusz, S.; Duber, S.; Kwiecińska, B.
The study of textural and structural transformations of carbonized anthracites Journal Article
In: Fuel Processing Technology, vol. 77-78, pp. 173-180, 2002, ISSN: 03783820, (24).
@article{2-s2.0-17444437540,
title = {The study of textural and structural transformations of carbonized anthracites},
author = { S. Pusz and S. Duber and B. Kwiecińska},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-17444437540&doi=10.1016%2fS0378-3820%2802%2900068-1&partnerID=40&md5=eb634306eb71050ff7e24ee55c962346},
doi = {10.1016/S0378-3820(02)00068-1},
issn = {03783820},
year = {2002},
date = {2002-01-01},
journal = {Fuel Processing Technology},
volume = {77-78},
pages = {173-180},
abstract = {Specific physical and chemical properties of anthracites may be explained by the differences in chemical structure of basic structural units (BSUs) and in various spatial arrangements of BSUs, that is, the texture. The structure and the texture of anthracites correspond with their optical properties. Thermal treatment causes the changes in the structure of BSUs and rearrangement of the texture of anthracites. The character of structural and textural transformation could be determined based on the reflectance values of anthracites. Various anthracites were thermally treated to the temperature of 1800 °C. Maximum (Rmax) and minimum (Rmin) reflectance values were measured and reflectance indicatrix parameters (Rev, Rst and Ram) were calculated for initial and heated samples. It was found that Rmax, Rmin and Rev values increase together with the temperature up to 1200-1400 °C. In higher temperatures, they start to decrease, while Ram parameter depending on anisotropy of the texture still increases to the final temperature of 1800 °C. That indicates gradual and soft transformation of the structure and the texture of anthracites up to the temperature 1200-1400 °C (arrangement of turbostratic structure) and some disturbances in textural order before the stage of graphitization. © 2002 Elsevier Science B.V. All rights reserved.},
note = {24},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Specific physical and chemical properties of anthracites may be explained by the differences in chemical structure of basic structural units (BSUs) and in various spatial arrangements of BSUs, that is, the texture. The structure and the texture of anthracites correspond with their optical properties. Thermal treatment causes the changes in the structure of BSUs and rearrangement of the texture of anthracites. The character of structural and textural transformation could be determined based on the reflectance values of anthracites. Various anthracites were thermally treated to the temperature of 1800 °C. Maximum (Rmax) and minimum (Rmin) reflectance values were measured and reflectance indicatrix parameters (Rev, Rst and Ram) were calculated for initial and heated samples. It was found that Rmax, Rmin and Rev values increase together with the temperature up to 1200-1400 °C. In higher temperatures, they start to decrease, while Ram parameter depending on anisotropy of the texture still increases to the final temperature of 1800 °C. That indicates gradual and soft transformation of the structure and the texture of anthracites up to the temperature 1200-1400 °C (arrangement of turbostratic structure) and some disturbances in textural order before the stage of graphitization. © 2002 Elsevier Science B.V. All rights reserved.
Duber, S.; Rouzaud, J. N.; Clinard, C.; Pusz, S.
Microporosity and optical properties of some activated chars Journal Article
In: Fuel Processing Technology, vol. 77-78, pp. 221-227, 2002, ISSN: 03783820, (16).
@article{2-s2.0-0005801140,
title = {Microporosity and optical properties of some activated chars},
author = { S. Duber and J.N. Rouzaud and C. Clinard and S. Pusz},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0005801140&doi=10.1016%2fS0378-3820%2802%2900050-4&partnerID=40&md5=fd0e6eb9a9fa025fdd6e96b362206d9c},
doi = {10.1016/S0378-3820(02)00050-4},
issn = {03783820},
year = {2002},
date = {2002-01-01},
journal = {Fuel Processing Technology},
volume = {77-78},
pages = {221-227},
abstract = {The aim of this work was to understand the structural and microtextural changes responsible for microporosity formation in saccharose-based chars activated with CO2 at 850 °C. High-resolution transmission electron microscopy (HRTEM) and optical microscopy (reflectance measurements) allow to follow the changes in the chars organisation from nanometric to micrometric scales. Quantitative structural and microtextural data can now be extracted from the HRTEM images with an in-house image analysis procedure. Our results allow to suggest that the development of the microporosity with an increasing burn-off could be due to the development of slit-shaped pores. Such changes in pore shape and dimensions affect optical properties; a relationship was established between BET surface area and mean reflectance. By coupling these experimental data and a theoretical approach, a model of activated carbons is proposed to explain the reflectance changes during activation. © 2002 Elsevier Science B.V. All rights reserved.},
note = {16},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The aim of this work was to understand the structural and microtextural changes responsible for microporosity formation in saccharose-based chars activated with CO2 at 850 °C. High-resolution transmission electron microscopy (HRTEM) and optical microscopy (reflectance measurements) allow to follow the changes in the chars organisation from nanometric to micrometric scales. Quantitative structural and microtextural data can now be extracted from the HRTEM images with an in-house image analysis procedure. Our results allow to suggest that the development of the microporosity with an increasing burn-off could be due to the development of slit-shaped pores. Such changes in pore shape and dimensions affect optical properties; a relationship was established between BET surface area and mean reflectance. By coupling these experimental data and a theoretical approach, a model of activated carbons is proposed to explain the reflectance changes during activation. © 2002 Elsevier Science B.V. All rights reserved.
Burian, A.; Szczygielska, A.; Kołoczek, J.; Dore, J. C.; Honkimäki, V.; Duber, S.
Curved surfaces in disordered carbons by high energy X-ray scattering Journal Article
In: Acta Physica Polonica A, vol. 101, no. 5, pp. 751-759, 2002, ISSN: 05874246, (6).
@article{2-s2.0-31244437024,
title = {Curved surfaces in disordered carbons by high energy X-ray scattering},
author = { A. Burian and A. Szczygielska and J. Kołoczek and J.C. Dore and V. Honkimäki and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-31244437024&doi=10.12693%2fAPhysPolA.101.751&partnerID=40&md5=63d4c27070c5b8f9f727f991aa11736e},
doi = {10.12693/APhysPolA.101.751},
issn = {05874246},
year = {2002},
date = {2002-01-01},
journal = {Acta Physica Polonica A},
volume = {101},
number = {5},
pages = {751-759},
publisher = {Polish Academy of Sciences},
abstract = {Disordered carbons prepared by slow pyrolysis of saccharose and anthracene and subsequent heat treatment at 1000°C and 2300°C have been studied by high energy X-ray diffraction. Computer simulations of the powder diffraction patterns of fullerenes, nanotubes and carbon models have been compared with the experimental data after conversion to real space via the Fourier transform. The presence of fullerene- and nanotube-like fragments with non-six membered rings in the investigated samples has been deduced by detailed analysis of the radial distribution functions of the saccharose- and anthracene-based carbons and related to resistance to graphitization of the saccharose-based carbons and to stability of the growing crystallites in the case of the anthracene-based carbons. The obtained results are compared to high resolution electron microscopy and Raman studies.},
note = {6},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Disordered carbons prepared by slow pyrolysis of saccharose and anthracene and subsequent heat treatment at 1000°C and 2300°C have been studied by high energy X-ray diffraction. Computer simulations of the powder diffraction patterns of fullerenes, nanotubes and carbon models have been compared with the experimental data after conversion to real space via the Fourier transform. The presence of fullerene- and nanotube-like fragments with non-six membered rings in the investigated samples has been deduced by detailed analysis of the radial distribution functions of the saccharose- and anthracene-based carbons and related to resistance to graphitization of the saccharose-based carbons and to stability of the growing crystallites in the case of the anthracene-based carbons. The obtained results are compared to high resolution electron microscopy and Raman studies.
Szczygielska, A.; Burian, A.; Duber, S.; Dore, J. C.; Honkimäki, V.
Structural studies of saccharose- and anthracene-based carbons by high energy X-ray scattering Proceedings
Elsevier Inc., vol. 144, 2002, ISSN: 01672991.
@proceedings{2-s2.0-0036932035,
title = {Structural studies of saccharose- and anthracene-based carbons by high energy X-ray scattering},
author = { A. Szczygielska and A. Burian and S. Duber and J.C. Dore and V. Honkimäki},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0036932035&doi=10.1016%2fs0167-2991%2802%2980181-1&partnerID=40&md5=01f4246a9de55d2a2cfc97512546cbb4},
doi = {10.1016/s0167-2991(02)80181-1},
issn = {01672991},
year = {2002},
date = {2002-01-01},
journal = {Studies in Surface Science and Catalysis},
volume = {144},
pages = {561-568},
publisher = {Elsevier Inc.},
abstract = {A series of porous carbon materials, produced by pyrolysis of saccharose and anthracene and heat-treated at 1000°C, 1900°C and 2300°C have been studied by wide-angle X-ray scattering. The X-ray data were collected at European Synchrotron Radiation Facility (ESRF) in Grenoble on the ID15 beam line (high-energy X-ray diffraction) using the wavelength λ=0,1067Å. (E=116,2 keV). The data were recorded in the scattering-vector range from 0.5 to 24Å-1 which allowed to conversion to real space via the Fourier transform yielding the radial distribution function of a good quality. Analysis of the experimental radial distribution function shows that carbons produced from anthracene transforms into graphite at 1900°C and this process is almost complete at 2300°C. The saccharose-based carbons remain disordered even at high temperature.},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
A series of porous carbon materials, produced by pyrolysis of saccharose and anthracene and heat-treated at 1000°C, 1900°C and 2300°C have been studied by wide-angle X-ray scattering. The X-ray data were collected at European Synchrotron Radiation Facility (ESRF) in Grenoble on the ID15 beam line (high-energy X-ray diffraction) using the wavelength λ=0,1067Å. (E=116,2 keV). The data were recorded in the scattering-vector range from 0.5 to 24Å-1 which allowed to conversion to real space via the Fourier transform yielding the radial distribution function of a good quality. Analysis of the experimental radial distribution function shows that carbons produced from anthracene transforms into graphite at 1900°C and this process is almost complete at 2300°C. The saccharose-based carbons remain disordered even at high temperature.
2001
Burian, A.; Daniel, P.; Duber, S.; Dore, J. C.
Raman scattering studies of the graphitization process in anthracene- and saccharose-based carbons Journal Article
In: Philosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties, vol. 81, no. 5, pp. 525-540, 2001, ISSN: 13642812, (14).
@article{2-s2.0-0035353679,
title = {Raman scattering studies of the graphitization process in anthracene- and saccharose-based carbons},
author = { A. Burian and P. Daniel and S. Duber and J.C. Dore},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0035353679&doi=10.1080%2f13642810110044988&partnerID=40&md5=669a0d364eae6321292e899ecea15990},
doi = {10.1080/13642810110044988},
issn = {13642812},
year = {2001},
date = {2001-01-01},
journal = {Philosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties},
volume = {81},
number = {5},
pages = {525-540},
abstract = {We report Raman scattering studies of the graphitization process in a series of carbons produced by the pyrolysis of saccharose and anthracene and then annealed at 1000, 1900 and 2300°C. Using 488 nm light, the first- and second-order Raman spectra of six samples have been examined in the range 50-4000 cm-1. The low-frequency Raman range 50-1000 cm-1 has been carefully examined using the laser excitation wavelengths 457.2, 476.5, 488.0 and 514.3 nm. A dependence of the Raman spectra in the first- and second-order ranges on annealing temperature and degree and size of ordered domains has been observed and correlated with neutron diffraction observations, indicating almost complete graphitization of the carbon prepared from anthracene and a disordered structure of the saccharose carbon at 2300°C. The occurrence of a sharp peak at about 464 cm-1 and broadened peaks in the range 75-210 cm-1, which shift with excitation energy as result of the one-dimensional quantum confinement effect of electrons in such structures, provide evidence for the presence of fullerene- and nanotube-like elements in the investigated materials. The presence of curved elements with odd-membered rings at an early stage of preparation and their sizeable increase at higher temperatures distinguish non-graphitizing from graphitizing carbons.},
note = {14},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report Raman scattering studies of the graphitization process in a series of carbons produced by the pyrolysis of saccharose and anthracene and then annealed at 1000, 1900 and 2300°C. Using 488 nm light, the first- and second-order Raman spectra of six samples have been examined in the range 50-4000 cm-1. The low-frequency Raman range 50-1000 cm-1 has been carefully examined using the laser excitation wavelengths 457.2, 476.5, 488.0 and 514.3 nm. A dependence of the Raman spectra in the first- and second-order ranges on annealing temperature and degree and size of ordered domains has been observed and correlated with neutron diffraction observations, indicating almost complete graphitization of the carbon prepared from anthracene and a disordered structure of the saccharose carbon at 2300°C. The occurrence of a sharp peak at about 464 cm-1 and broadened peaks in the range 75-210 cm-1, which shift with excitation energy as result of the one-dimensional quantum confinement effect of electrons in such structures, provide evidence for the presence of fullerene- and nanotube-like elements in the investigated materials. The presence of curved elements with odd-membered rings at an early stage of preparation and their sizeable increase at higher temperatures distinguish non-graphitizing from graphitizing carbons.
Burian, A.; Daniel, P.; Duber, S.; Dore, J. C.
Raman scattering studies of the graphitization process in anthracene- and saccharose-based carbons Journal Article
In: Philosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties, vol. 81, no. 5, pp. 525-540, 2001, ISSN: 13642812, (1).
@article{2-s2.0-84889306266,
title = {Raman scattering studies of the graphitization process in anthracene- and saccharose-based carbons},
author = { A. Burian and P. Daniel and S. Duber and J.C. Dore},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84889306266&doi=10.1080%2f13642810108225448&partnerID=40&md5=16865b2cabac23c7e5a7bea116a98264},
doi = {10.1080/13642810108225448},
issn = {13642812},
year = {2001},
date = {2001-01-01},
journal = {Philosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties},
volume = {81},
number = {5},
pages = {525-540},
abstract = {We report Raman scattering studies of the graphitization process in a series of carbons produced by the pyrolysis of saccharose and anthracene and then annealed at 1000, 1900 and 2300°C. Using 488 nm light, the first- and second-order Raman spectra of six samples have been examined in the range 50-4000cm−1. The low-frequency Raman range 50-lOOOcn−1 has been carefully examined using the laser excitation wavelengths 457.2, 476.5, 488.0 and 514.3 nm. A dependence of the Raman spectra in the first- and second-order ranges on annealing temperature and degree and size of ordered domains has been observed and correlated with neutron diffraction observations, indicating almost complete graphitization of the carbon prepared from anthracene and a disordered structure of the saccharose carbon at 2300°C. The occurrence of a sharp peak at about 464cm−1 and broadened peaks in the range 75-210cm−1, which shift with excitation energy as result of the one-dimensional auantum confinement effect of electrons in such structures, provide evidence for the presence of fullerene- and nanotube-like elements in the investigated materials. The presence of curved elements with odd-membered rings at an early stage of preparation and their sizeable increase at higher temperatures distinguish non-graphitizing from graphitizing carbons. © 2001 Taylor & Francis Group, LLC.},
note = {1},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report Raman scattering studies of the graphitization process in a series of carbons produced by the pyrolysis of saccharose and anthracene and then annealed at 1000, 1900 and 2300°C. Using 488 nm light, the first- and second-order Raman spectra of six samples have been examined in the range 50-4000cm−1. The low-frequency Raman range 50-lOOOcn−1 has been carefully examined using the laser excitation wavelengths 457.2, 476.5, 488.0 and 514.3 nm. A dependence of the Raman spectra in the first- and second-order ranges on annealing temperature and degree and size of ordered domains has been observed and correlated with neutron diffraction observations, indicating almost complete graphitization of the carbon prepared from anthracene and a disordered structure of the saccharose carbon at 2300°C. The occurrence of a sharp peak at about 464cm−1 and broadened peaks in the range 75-210cm−1, which shift with excitation energy as result of the one-dimensional auantum confinement effect of electrons in such structures, provide evidence for the presence of fullerene- and nanotube-like elements in the investigated materials. The presence of curved elements with odd-membered rings at an early stage of preparation and their sizeable increase at higher temperatures distinguish non-graphitizing from graphitizing carbons. © 2001 Taylor & Francis Group, LLC.
Szczygielska, A.; Burian, A.; Duber, S.; Dore, J. C.; Honkimäki, V.
Radial distribution function analysis of the graphitization process in carbon materials Journal Article
In: Journal of Alloys and Compounds, vol. 328, no. 1-2, pp. 231-236, 2001, ISSN: 09258388, (24).
@article{2-s2.0-0035807486,
title = {Radial distribution function analysis of the graphitization process in carbon materials},
author = { A. Szczygielska and A. Burian and S. Duber and J.C. Dore and V. Honkimäki},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0035807486&doi=10.1016%2fS0925-8388%2801%2901694-2&partnerID=40&md5=2d46dd706f5fff8bc3b4662b80029dd8},
doi = {10.1016/S0925-8388(01)01694-2},
issn = {09258388},
year = {2001},
date = {2001-01-01},
journal = {Journal of Alloys and Compounds},
volume = {328},
number = {1-2},
pages = {231-236},
abstract = {X-ray scattering studies of the graphitization process of saccharose- and anthracene-based carbons are reported. The scattered intensities were recorded in the scattering vector range from 0.6 to 24 Å-1, yielding a radial distribution function of good quality. Analysis of the first three peaks of the radial distribution function allowed us to establish a hexagonal structure within a single layer. In the early stage of preparation, both carbons exhibit a disordered structure in which graphite layers are stacked without spatial correlation, i.e. the turbostatic structure. The inter-layer spacings were estimated to be in the range from 3.6 to 3.37 Å. At higher temperatures the graphite-like layers exhibit an increasing ordering tendency within a single layer and in the c-axis. However, the degree of ordering is much higher for the anthracene-based carbons than the carbons prepared from saccharose, which remain disordered even at 2300°C. © 2001 Elsevier Science B.V. All rights reserved.},
note = {24},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
X-ray scattering studies of the graphitization process of saccharose- and anthracene-based carbons are reported. The scattered intensities were recorded in the scattering vector range from 0.6 to 24 Å-1, yielding a radial distribution function of good quality. Analysis of the first three peaks of the radial distribution function allowed us to establish a hexagonal structure within a single layer. In the early stage of preparation, both carbons exhibit a disordered structure in which graphite layers are stacked without spatial correlation, i.e. the turbostatic structure. The inter-layer spacings were estimated to be in the range from 3.6 to 3.37 Å. At higher temperatures the graphite-like layers exhibit an increasing ordering tendency within a single layer and in the c-axis. However, the degree of ordering is much higher for the anthracene-based carbons than the carbons prepared from saccharose, which remain disordered even at 2300°C. © 2001 Elsevier Science B.V. All rights reserved.
2000
Saranchuk, V. I.; Tamko, V. A.; Matsenko, G. P.; Duber, S.; Shvets, I. I.
Coal clays of the Dnieper brown coal basin. Composition and properties Journal Article
In: Solid Fuel Chemistry, vol. 34, no. 3, pp. 73-79, 2000, ISSN: 03615219.
@article{2-s2.0-77949707922,
title = {Coal clays of the Dnieper brown coal basin. Composition and properties},
author = { V.I. Saranchuk and V.A. Tamko and G.P. Matsenko and S. Duber and I.I. Shvets},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77949707922&partnerID=40&md5=60b0254a20b03979bfcbcd1355faac6e},
issn = {03615219},
year = {2000},
date = {2000-01-01},
journal = {Solid Fuel Chemistry},
volume = {34},
number = {3},
pages = {73-79},
abstract = {The results of studying coal clays by optical microscopy, EPR, and IR spectroscopy are presented. A scheme for their complex processing is proposed. © 2000 by Allerton Press. Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The results of studying coal clays by optical microscopy, EPR, and IR spectroscopy are presented. A scheme for their complex processing is proposed. © 2000 by Allerton Press. Inc.
Duber, S.; Pusz, S.; Kwiecińska, B.; Rouzaud, J. N.
On the optically biaxial character and heterogeneity of anthracites Journal Article
In: International Journal of Coal Geology, vol. 44, no. 3-4, pp. 227-250, 2000, ISSN: 01665162, (55).
@article{2-s2.0-0034283171,
title = {On the optically biaxial character and heterogeneity of anthracites},
author = { S. Duber and S. Pusz and B. Kwiecińska and J.N. Rouzaud},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0034283171&doi=10.1016%2fS0166-5162%2800%2900012-4&partnerID=40&md5=93fd6df68e7bc8e20d3c1553804ebe88},
doi = {10.1016/S0166-5162(00)00012-4},
issn = {01665162},
year = {2000},
date = {2000-01-01},
journal = {International Journal of Coal Geology},
volume = {44},
number = {3-4},
pages = {227-250},
abstract = {The results of the study of optical properties of 13 anthracites from different parts of the world are presented in this paper. Measurements of reflectance values were made on non-oriented vitrinite grains for a minimum of 300 points per sample. The reconstruction of Reflectance Indicating Surfaces (RIS) were made by Kilby's method [Kilby, W.E., 1988. Recognition of vitrinite with non-uniaxial negative reflectance characteristics. Int. J. Coal Geol. 9, 267-285; Kilby, W.E., 1991. Vitrinite reflectance measurement - some technique enhancements and relationships. Int. J. Coal Geol. 19, 201-218]. It was found that the use of Kilby's method for strongly anisotropic materials like anthracites did not give unambiguous results. Some improvement in Kilby's method, consisting of the division of the cumulative cross-plot into several elemental components, is suggested. Each elemental cross-plot corresponds to a textural class of anthracite, which is characterized by the values of RIS main axes R(MAX)((k)), R(INT)((k)) and R(MIN)((k)) (k = 1,2,... n; n - number of classes). The global texture of anthracite is characterized as a RIS with main axes calculated as the weighted means of R(MAX), R(INT) and R(MIN) for each class of this anthracite. The division of cumulative Kilby's cross-plot on elemental components makes possible the calculation of new coefficients H(t) and H10 characterizing the heterogeneity of the structure and texture of anthracites. The results of our study show that all anthracites have biaxial negative textures, but their heterogeneity varies in a wide range of H(t) and H10 coefficients depending upon the individual coal basin. (C) 2000 Elsevier Science B.V. All rights reserved.The results of the study of optical properties of 13 anthracites from different parts of the world are presented in this paper. Measurements of reflectance values were made on non-oriented vitrinite grains for a minimum of 300 points per sample. The reconstruction of Reflectance Indicating Surfaces (RIS) were made by Kilby's method. It was found that the use of Kilby's method for strongly anisotropic materials like anthracites did not give unambiguous results. Some improvement in Kilby's method, consisting of the division of the cumulative cross-plot into several elemental components, is suggested. Each elemental cross-plot corresponds to a textural class of anthracite, which is characterized by the values of RIS main axes RMAX(k), RINT(k) and RMIN(k) (k = 1,2, ... n; n - number of classes). The global texture of anthracite is characterized as a RIS with main axes calculated as the weighted means of RMAX̄, RINT̄ and RMIN̄ for each class of this anthracite. The division of cumulative Kilby's cross-plot on elemental components makes possible the calculation of new coefficients Ht and H10 characterizing the heterogeneity of the structure and texture of anthracites. The results of our study show that all anthracites have biaxial negative textures, but their heterogeneity varies in a wide range of Ht and H10 coefficients depending upon the individual coal basin.},
note = {55},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The results of the study of optical properties of 13 anthracites from different parts of the world are presented in this paper. Measurements of reflectance values were made on non-oriented vitrinite grains for a minimum of 300 points per sample. The reconstruction of Reflectance Indicating Surfaces (RIS) were made by Kilby's method [Kilby, W.E., 1988. Recognition of vitrinite with non-uniaxial negative reflectance characteristics. Int. J. Coal Geol. 9, 267-285; Kilby, W.E., 1991. Vitrinite reflectance measurement - some technique enhancements and relationships. Int. J. Coal Geol. 19, 201-218]. It was found that the use of Kilby's method for strongly anisotropic materials like anthracites did not give unambiguous results. Some improvement in Kilby's method, consisting of the division of the cumulative cross-plot into several elemental components, is suggested. Each elemental cross-plot corresponds to a textural class of anthracite, which is characterized by the values of RIS main axes R(MAX)((k)), R(INT)((k)) and R(MIN)((k)) (k = 1,2,... n; n - number of classes). The global texture of anthracite is characterized as a RIS with main axes calculated as the weighted means of R(MAX), R(INT) and R(MIN) for each class of this anthracite. The division of cumulative Kilby's cross-plot on elemental components makes possible the calculation of new coefficients H(t) and H10 characterizing the heterogeneity of the structure and texture of anthracites. The results of our study show that all anthracites have biaxial negative textures, but their heterogeneity varies in a wide range of H(t) and H10 coefficients depending upon the individual coal basin. (C) 2000 Elsevier Science B.V. All rights reserved.The results of the study of optical properties of 13 anthracites from different parts of the world are presented in this paper. Measurements of reflectance values were made on non-oriented vitrinite grains for a minimum of 300 points per sample. The reconstruction of Reflectance Indicating Surfaces (RIS) were made by Kilby's method. It was found that the use of Kilby's method for strongly anisotropic materials like anthracites did not give unambiguous results. Some improvement in Kilby's method, consisting of the division of the cumulative cross-plot into several elemental components, is suggested. Each elemental cross-plot corresponds to a textural class of anthracite, which is characterized by the values of RIS main axes RMAX(k), RINT(k) and RMIN(k) (k = 1,2, ... n; n - number of classes). The global texture of anthracite is characterized as a RIS with main axes calculated as the weighted means of RMAX̄, RINT̄ and RMIN̄ for each class of this anthracite. The division of cumulative Kilby's cross-plot on elemental components makes possible the calculation of new coefficients Ht and H10 characterizing the heterogeneity of the structure and texture of anthracites. The results of our study show that all anthracites have biaxial negative textures, but their heterogeneity varies in a wide range of Ht and H10 coefficients depending upon the individual coal basin.
Harris, P. J. F.; Burian, A.; Duber, S.
High-resolution electron microscopy of a microporous carbon Journal Article
In: Philosophical Magazine Letters, vol. 80, no. 6, pp. 381-386, 2000, ISSN: 09500839, (110).
@article{2-s2.0-0034211174,
title = {High-resolution electron microscopy of a microporous carbon},
author = { P.J.F. Harris and A. Burian and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0034211174&doi=10.1080%2f095008300403512&partnerID=40&md5=f1b5ff36995034017421221c3ebcfa9a},
doi = {10.1080/095008300403512},
issn = {09500839},
year = {2000},
date = {2000-01-01},
journal = {Philosophical Magazine Letters},
volume = {80},
number = {6},
pages = {381-386},
abstract = {The structure of a microporous carbon prepared by the carbonization of sucrose was examined using high-resolution electron microscopy. It was found to be disordered and isotropic and primarily made up of tightly curved individual carbon layers, enclosing pores typically about 1 nm in size. Completely closed carbon particles were also present. These observations suggest that the carbon may have a fullerene-related structure, in which pentagons and heptagons are distributed randomly throughout a hexagonal network, producing continuous curvature.},
note = {110},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The structure of a microporous carbon prepared by the carbonization of sucrose was examined using high-resolution electron microscopy. It was found to be disordered and isotropic and primarily made up of tightly curved individual carbon layers, enclosing pores typically about 1 nm in size. Completely closed carbon particles were also present. These observations suggest that the carbon may have a fullerene-related structure, in which pentagons and heptagons are distributed randomly throughout a hexagonal network, producing continuous curvature.
1999
Duber, S.; Rouzaud, J. N.
Calculation of relectance values for two models of texture of carbon materials Journal Article
In: International Journal of Coal Geology, vol. 38, no. 3-4, pp. 333-348, 1999, ISSN: 01665162, (32).
@article{2-s2.0-0032712461,
title = {Calculation of relectance values for two models of texture of carbon materials},
author = { S. Duber and J.N. Rouzaud},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0032712461&doi=10.1016%2fS0166-5162%2898%2900037-8&partnerID=40&md5=2bd18796955cdc28d2544aad496ab357},
doi = {10.1016/S0166-5162(98)00037-8},
issn = {01665162},
year = {1999},
date = {1999-01-01},
journal = {International Journal of Coal Geology},
volume = {38},
number = {3-4},
pages = {333-348},
publisher = {Elsevier B.V.},
abstract = {This paper presents two models of texture of carbon materials possessing porosity. For both models, R(MAX), R(INT) and R(MIN) values of reflectance have been calculated by modified Ting's 3A method [Ting, F.T.C., 1978. Petrographic techniques in coal analysis. In: C. Karr (Ed.), Analytical Methods for Coal and Coal Products, Vol. 1. Academic Press, New York, 1978, pp. 3-25]. It has been found that the reflectance indicating surface (RIS) for the studied models of texture changes from a biaxial negative up to a biaxial positive one (the type A texture) depending on the shape and size of pores. In particular case, for the type B texture and the isometry of pores, a uniaxial negative RIS is merely obtained.},
note = {32},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This paper presents two models of texture of carbon materials possessing porosity. For both models, R(MAX), R(INT) and R(MIN) values of reflectance have been calculated by modified Ting's 3A method [Ting, F.T.C., 1978. Petrographic techniques in coal analysis. In: C. Karr (Ed.), Analytical Methods for Coal and Coal Products, Vol. 1. Academic Press, New York, 1978, pp. 3-25]. It has been found that the reflectance indicating surface (RIS) for the studied models of texture changes from a biaxial negative up to a biaxial positive one (the type A texture) depending on the shape and size of pores. In particular case, for the type B texture and the isometry of pores, a uniaxial negative RIS is merely obtained.
1998
Butuzova, L. F.; Krztoń, A.; Saranchuk, V. I.; Kozlova, I. V.; Duber, S.; Gey, Zh. M.
Structural chemical transformations of modified brown coal in pyrolysis and hydrogenation Journal Article
In: Solid Fuel Chemistry, vol. 32, no. 4, pp. 42-52, 1998, ISSN: 03615219.
@article{2-s2.0-77949748899,
title = {Structural chemical transformations of modified brown coal in pyrolysis and hydrogenation},
author = { L.F. Butuzova and A. Krztoń and V.I. Saranchuk and I.V. Kozlova and S. Duber and Zh.M. Gey},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77949748899&partnerID=40&md5=b12a3ac3a8be04d16f6228ecf3db5084},
issn = {03615219},
year = {1998},
date = {1998-01-01},
journal = {Solid Fuel Chemistry},
volume = {32},
number = {4},
pages = {42-52},
abstract = {IR spectroscopy of diffuse reflection with Fourier transformation, EPR spectroscopy, and X-ray structural analysis were used to study the influence of treatment of brown coals with solutions of alkalies and acids on the composition and structure of the products formed in pyrolysis and hydrogenation. It is shown that acid and alkaline modification leads to the appearance of a new type of paramagnetic centers, to a change in the way of packing of the aromatic rings in the organic matter of the coal, and also to a change in the yield and supermolecular structure of the thermal destruction products. © 1998 by Allerton Press. Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
IR spectroscopy of diffuse reflection with Fourier transformation, EPR spectroscopy, and X-ray structural analysis were used to study the influence of treatment of brown coals with solutions of alkalies and acids on the composition and structure of the products formed in pyrolysis and hydrogenation. It is shown that acid and alkaline modification leads to the appearance of a new type of paramagnetic centers, to a change in the way of packing of the aromatic rings in the organic matter of the coal, and also to a change in the yield and supermolecular structure of the thermal destruction products. © 1998 by Allerton Press. Inc.
Butuzova, L. F.; Krshton', A.; Saranchuk, V. I.; Kozlova, I. V.; Duber, S.; Ge, Zh. M.
Structural chemical transformations of modified lignite upon pyrolysis and hydrogenation processes Journal Article
In: Chongqing Jianzhu Daxue Xuebao/Journal of Chongqing Jianzhu University, vol. 20, no. 5, pp. 36-45, 1998, ISSN: 10067329.
@article{2-s2.0-0031611914,
title = {Structural chemical transformations of modified lignite upon pyrolysis and hydrogenation processes},
author = { L.F. Butuzova and A. Krshton' and V.I. Saranchuk and I.V. Kozlova and S. Duber and Zh.M. Ge},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0031611914&partnerID=40&md5=c03fa2cedb846bfb8ce06ab0bd43c2d9},
issn = {10067329},
year = {1998},
date = {1998-01-01},
journal = {Chongqing Jianzhu Daxue Xuebao/Journal of Chongqing Jianzhu University},
volume = {20},
number = {5},
pages = {36-45},
publisher = {China International Publication Trading Corporation, Beijing, China},
abstract = {Effect of lignite treatment with alkaline and acid solutions on the structure and composition of lignite pyrolysis and hydrogenation products has been studied using Fourier transform infrared spectroscopy, electron spin resonance spectroscopy, and X ray diffraction analysis. It is shown that the acid-base modification results in the changes of aromatics structure in the coal organic mass as well as changes in the yield and supermolecular structure of pyrolysis products.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Effect of lignite treatment with alkaline and acid solutions on the structure and composition of lignite pyrolysis and hydrogenation products has been studied using Fourier transform infrared spectroscopy, electron spin resonance spectroscopy, and X ray diffraction analysis. It is shown that the acid-base modification results in the changes of aromatics structure in the coal organic mass as well as changes in the yield and supermolecular structure of pyrolysis products.
1997
Butuzova, L. F.; Duber, S.; Matsenko, G. P.; Saranchuk, V. I.; Rouzaud, J. N.
The microtexture and microstructure of cokes prepared with calcium hydroxide additives Journal Article
In: Solid Fuel Chemistry, vol. 31, no. 4, pp. 23-33, 1997, ISSN: 03615219.
@article{2-s2.0-77949728412,
title = {The microtexture and microstructure of cokes prepared with calcium hydroxide additives},
author = { L.F. Butuzova and S. Duber and G.P. Matsenko and V.I. Saranchuk and J.N. Rouzaud},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-77949728412&partnerID=40&md5=1dc88bfad500d14e6df14b89db7ce3f6},
issn = {03615219},
year = {1997},
date = {1997-01-01},
journal = {Solid Fuel Chemistry},
volume = {31},
number = {4},
pages = {23-33},
abstract = {The influence of the chemical modification of coal on the structure, microstructure, and properties of coke is shown. The use of optical and X-ray structural methods of analysis made it possible to determine the action of a calcium hydroxide additive on the structure of samples. It was found that in the presence of an additive, the total content of lamellas, the content of flat ones (transmission electron microscopy), and the amount of a fluid domain texture (optical microscopy) increase together with an increase in the thickness of the pore walls in the relevant cokes. © 1997 by Allerton Press, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The influence of the chemical modification of coal on the structure, microstructure, and properties of coke is shown. The use of optical and X-ray structural methods of analysis made it possible to determine the action of a calcium hydroxide additive on the structure of samples. It was found that in the presence of an additive, the total content of lamellas, the content of flat ones (transmission electron microscopy), and the amount of a fluid domain texture (optical microscopy) increase together with an increase in the thickness of the pore walls in the relevant cokes. © 1997 by Allerton Press, Inc.
Butuzova, L. F.; Duber, S.; Matsenko, G. P.; Saranchuk, V. I.; Ruzo, Zh. N.
Microtexture and microstructure of cokes with calcium hydroxide additives Journal Article
In: Khimiya Tverdogo Topliva, no. 4, pp. 21-31, 1997, ISSN: 00231177.
@article{2-s2.0-0031176551,
title = {Microtexture and microstructure of cokes with calcium hydroxide additives},
author = { L.F. Butuzova and S. Duber and G.P. Matsenko and V.I. Saranchuk and Zh.N. Ruzo},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0031176551&partnerID=40&md5=edd407eaeaef67c49d3273b03eed9f0a},
issn = {00231177},
year = {1997},
date = {1997-01-01},
journal = {Khimiya Tverdogo Topliva},
number = {4},
pages = {21-31},
abstract = {Effect of calcium hydroxide additive on microtexture and mechanical strength of a coke obtained as a result of the additive interaction with the coking coal is studied. The structure of coke samples was examined using optical and X ray diffraction methods. The data on total lamellae content, flat lamellae content (obtained with transmission electron microscopy), and the domain texture (obtained with optical microscopy) are presented.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Effect of calcium hydroxide additive on microtexture and mechanical strength of a coke obtained as a result of the additive interaction with the coking coal is studied. The structure of coke samples was examined using optical and X ray diffraction methods. The data on total lamellae content, flat lamellae content (obtained with transmission electron microscopy), and the domain texture (obtained with optical microscopy) are presented.
1993
Duber, S.; Mikosz, J.
Evidence for spin centres with S = 1 in bituminous coals Journal Article
In: Fuel, vol. 72, no. 2, pp. 267-269, 1993, ISSN: 00162361, (6).
@article{2-s2.0-0342490992,
title = {Evidence for spin centres with S = 1 in bituminous coals},
author = { S. Duber and J. Mikosz},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0342490992&doi=10.1016%2f0016-2361%2893%2990409-U&partnerID=40&md5=d56e7c58c9e75dd0a8339f1b79c96087},
doi = {10.1016/0016-2361(93)90409-U},
issn = {00162361},
year = {1993},
date = {1993-01-01},
journal = {Fuel},
volume = {72},
number = {2},
pages = {267-269},
abstract = {[No abstract available]},
note = {6},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
[No abstract available]
1988
Więckowski, A. B.; Duber, S.
Determination of the molecular phases in bituminous coal by the EPR method Journal Article
In: Ferroelectrics, vol. 80, no. 1, pp. 95-98, 1988, ISSN: 00150193, (1).
@article{2-s2.0-84972978630,
title = {Determination of the molecular phases in bituminous coal by the EPR method},
author = { A.B. Więckowski and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84972978630&doi=10.1080%2f00150198808223268&partnerID=40&md5=d4a281dd780c29fad67422d6dad13f30},
doi = {10.1080/00150198808223268},
issn = {00150193},
year = {1988},
date = {1988-01-01},
journal = {Ferroelectrics},
volume = {80},
number = {1},
pages = {95-98},
abstract = {By the EPR method the weight fractions of the molecular phases in coal were established. © 1988, Taylor & Francis Group, LLC. All rights reserved.},
note = {1},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
By the EPR method the weight fractions of the molecular phases in coal were established. © 1988, Taylor & Francis Group, LLC. All rights reserved.
1987
Kiselev, V.; Duber, S.; Jurkiewicz, A.
Study of the structure of asphaltenes by nuclear magnetic resonance Journal Article
In: Petroleum Chemistry: U.S.S.R, vol. 27, no. 1, pp. 80-87, 1987, ISSN: 00316458.
@article{2-s2.0-0023564714,
title = {Study of the structure of asphaltenes by nuclear magnetic resonance},
author = { V. Kiselev and S. Duber and A. Jurkiewicz},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0023564714&doi=10.1016%2f0031-6458%2887%2990026-8&partnerID=40&md5=66c7a0b43ef0ed89e0cfda64e9499337},
doi = {10.1016/0031-6458(87)90026-8},
issn = {00316458},
year = {1987},
date = {1987-01-01},
journal = {Petroleum Chemistry: U.S.S.R},
volume = {27},
number = {1},
pages = {80-87},
abstract = {[No abstract available]},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
[No abstract available]
Duber, S.; Wachowska, H. M.; Więckowski, A. B.
E.p.r. study of reduced and reductively ethylated coals Journal Article
In: Fuel, vol. 66, no. 8, pp. 1069-1072, 1987, ISSN: 00162361, (13).
@article{2-s2.0-0023398919,
title = {E.p.r. study of reduced and reductively ethylated coals},
author = { S. Duber and H.M. Wachowska and A.B. Więckowski},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0023398919&doi=10.1016%2f0016-2361%2887%2990302-4&partnerID=40&md5=63af1a2059d212da8d5d24dd6e85ad62},
doi = {10.1016/0016-2361(87)90302-4},
issn = {00162361},
year = {1987},
date = {1987-01-01},
journal = {Fuel},
volume = {66},
number = {8},
pages = {1069-1072},
abstract = {Two coals (78 and 85 wt % C) were reduced with potassium in tetrahydrofuran in the presence of naphthalene and also ethylated with ethyl iodide. The e.p.r. spectra of the coals and products consisted of two components: a narrow and a broad line. Both reduction and ethylation led to a decrease in concentration of paramagnetic centres; quenching was greater in centres related to the broad line component. A mechanism for the quenching is suggested. © 1987.},
note = {13},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Two coals (78 and 85 wt % C) were reduced with potassium in tetrahydrofuran in the presence of naphthalene and also ethylated with ethyl iodide. The e.p.r. spectra of the coals and products consisted of two components: a narrow and a broad line. Both reduction and ethylation led to a decrease in concentration of paramagnetic centres; quenching was greater in centres related to the broad line component. A mechanism for the quenching is suggested. © 1987.
1984
Duber, S.; Więckowski, A. B.
Excited triplet states in bituminous coal Journal Article
In: Fuel, vol. 63, no. 10, pp. 1474-1475, 1984, ISSN: 00162361, (14).
@article{2-s2.0-0041096263,
title = {Excited triplet states in bituminous coal},
author = { S. Duber and A.B. Więckowski},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0041096263&doi=10.1016%2f0016-2361%2884%2990363-6&partnerID=40&md5=a0242257eb6d666297545e1522ed29fd},
doi = {10.1016/0016-2361(84)90363-6},
issn = {00162361},
year = {1984},
date = {1984-01-01},
journal = {Fuel},
volume = {63},
number = {10},
pages = {1474-1475},
abstract = {The intensities of the broad and narrow lines constituting the e.p.r. spectrum of coal depend on the temperature of measurement. The system of paramagnetic centres related to the broad line does not obey the Curie law and consists of free radicals (S = 1 2) and of centres with singlet ground state (S = 0) and lowest-excited triplet state (S = 1). The singlet-triplet excitation energy, J, is comparable with thermal energy, kT, of lattice vibrations. The system of paramagnetic centres related to the narrow line obeys the Curie law (S = 1 2). © 1984.},
note = {14},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The intensities of the broad and narrow lines constituting the e.p.r. spectrum of coal depend on the temperature of measurement. The system of paramagnetic centres related to the broad line does not obey the Curie law and consists of free radicals (S = 1 2) and of centres with singlet ground state (S = 0) and lowest-excited triplet state (S = 1). The singlet-triplet excitation energy, J, is comparable with thermal energy, kT, of lattice vibrations. The system of paramagnetic centres related to the narrow line obeys the Curie law (S = 1 2). © 1984.
Duber, S.; Więckowski, A. B.
Effects of organic solvents on the EPR spectrum of coal Journal Article
In: Fuel, vol. 63, no. 12, pp. 1641-1644, 1984, ISSN: 00162361, (21).
@article{2-s2.0-0021616904,
title = {Effects of organic solvents on the EPR spectrum of coal},
author = { S. Duber and A.B. Więckowski},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0021616904&doi=10.1016%2f0016-2361%2884%2990092-9&partnerID=40&md5=deefbc28793b00395331b144d29f6ad7},
doi = {10.1016/0016-2361(84)90092-9},
issn = {00162361},
year = {1984},
date = {1984-01-01},
journal = {Fuel},
volume = {63},
number = {12},
pages = {1641-1644},
abstract = {EPR studies have been carried out on coal and the products of its extraction with ethylenediamine, pyridine and tetrahydrofuran. The spectrum of the coal and the residue after extraction consisted of two lines. In the case of the extraction residue the width of the narrow line remains practically unchanged compared to the initial coal whereas that of the broad component decreases. The extracts exhibit a single line with a width close to that of the broad component from the extraction residue. The concentration of paramagnetic centres in the residue and extracts is lower than in the coal. The decrease in concentration is higher when the extraction yield obtained with the solvent is higher. Quenching of paramagnetic centres is found to be related to the destruction of intermolecular bonds of the donor-acceptor type in the coal. © 1984.},
note = {21},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
EPR studies have been carried out on coal and the products of its extraction with ethylenediamine, pyridine and tetrahydrofuran. The spectrum of the coal and the residue after extraction consisted of two lines. In the case of the extraction residue the width of the narrow line remains practically unchanged compared to the initial coal whereas that of the broad component decreases. The extracts exhibit a single line with a width close to that of the broad component from the extraction residue. The concentration of paramagnetic centres in the residue and extracts is lower than in the coal. The decrease in concentration is higher when the extraction yield obtained with the solvent is higher. Quenching of paramagnetic centres is found to be related to the destruction of intermolecular bonds of the donor-acceptor type in the coal. © 1984.
1982
Duber, S.; Więckowski, A. B.
E.p.r. study of molecular phases in coal Journal Article
In: Fuel, vol. 61, no. 5, pp. 433-436, 1982, ISSN: 00162361, (45).
@article{2-s2.0-0000277205,
title = {E.p.r. study of molecular phases in coal},
author = { S. Duber and A.B. Więckowski},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0000277205&doi=10.1016%2f0016-2361%2882%2990067-9&partnerID=40&md5=a3e68fffa1f52de3378fc83ca8395261},
doi = {10.1016/0016-2361(82)90067-9},
issn = {00162361},
year = {1982},
date = {1982-01-01},
journal = {Fuel},
volume = {61},
number = {5},
pages = {433-436},
abstract = {E.p.r. spectra from coals of various carbon content are reported. The e.p.r. signal from coals in a vacuum consists of two lines with different widths. The results are interpreted using the Larsen-Kovac structural model (Am. Chem. Soc. Div. Fuel Chem. Preprints 1977, 22, 181). The paramagnetic centres, disposed in the macromolecular phase, give a narrow line whereas the spins of the molecular phase are responsible for the broad line. These results provide a good interpretation of the changes in e.p.r. signal-shape under the influence of various organic solvents observed by Yokokawa (Fuel 1968, 47, 273; Fuel 1969, 48, 29). © 1982.},
note = {45},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
E.p.r. spectra from coals of various carbon content are reported. The e.p.r. signal from coals in a vacuum consists of two lines with different widths. The results are interpreted using the Larsen-Kovac structural model (Am. Chem. Soc. Div. Fuel Chem. Preprints 1977, 22, 181). The paramagnetic centres, disposed in the macromolecular phase, give a narrow line whereas the spins of the molecular phase are responsible for the broad line. These results provide a good interpretation of the changes in e.p.r. signal-shape under the influence of various organic solvents observed by Yokokawa (Fuel 1968, 47, 273; Fuel 1969, 48, 29). © 1982.
1976
Kossobudzka, H.; Otlik, A.; Duber, S.
In: Polimery/Polymers, vol. 21, no. 8, pp. 354-357, 1976, ISSN: 00322725.
@article{2-s2.0-0016991040,
title = {Primary Results of Studies of the Nature of Changes in Polyacrylonitrile (PAN) Fibers During Heat Treatment. [WSTEPNE BADANIA ZMIAN ZACHODZACYCH WE WLOKACH PAN PODCZAS OBROBKI TERMICZNEJ.]},
author = { H. Kossobudzka and A. Otlik and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0016991040&partnerID=40&md5=d5cabb5c68ac00cdafdd6c921b69a6cd},
issn = {00322725},
year = {1976},
date = {1976-01-01},
journal = {Polimery/Polymers},
volume = {21},
number = {8},
pages = {354-357},
abstract = {General characteristics of PAN fibers' properties being important in the process of carbon fibers formation from Anilana fibers was presented. Some studies were made at various temperatures using X-ray and microscopy techniques on the determination of specific temperature values and ranges of transitions occurring during heat treatment of raw, oxidized and carbonized fibers and changes in their structure. The strongest changes of fibers were found at oxidizing treatment temperature; such fibers are characterized by high exothermic effect, change of crystallites symmetry and occurrence of optical anisotropy.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
General characteristics of PAN fibers' properties being important in the process of carbon fibers formation from Anilana fibers was presented. Some studies were made at various temperatures using X-ray and microscopy techniques on the determination of specific temperature values and ranges of transitions occurring during heat treatment of raw, oxidized and carbonized fibers and changes in their structure. The strongest changes of fibers were found at oxidizing treatment temperature; such fibers are characterized by high exothermic effect, change of crystallites symmetry and occurrence of optical anisotropy.
Kossobudzka, H.; Otlik, A.; Duber, S.
Some initial studies of the nature of changes in polyacrylonitrile (PAN) fibres during heat treatment Journal Article
In: 1976.
@article{2-s2.0-0016898740,
title = {Some initial studies of the nature of changes in polyacrylonitrile (PAN) fibres during heat treatment},
author = { H. Kossobudzka and A. Otlik and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0016898740&partnerID=40&md5=3e9291c1d79cbbddff21ff1cb3093c2f},
year = {1976},
date = {1976-01-01},
abstract = {[No abstract available]},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
[No abstract available]
Kossobudzka, H.; Otlik, A.; Duber, S.
Preliminary studies of the changes occurring in polyacrylonitrile fibres during heat treatment Journal Article
In: 1976.
@article{2-s2.0-0016885316,
title = {Preliminary studies of the changes occurring in polyacrylonitrile fibres during heat treatment},
author = { H. Kossobudzka and A. Otlik and S. Duber},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0016885316&partnerID=40&md5=c24a1e2e588589de8fd9bffe3f9cac0d},
year = {1976},
date = {1976-01-01},
abstract = {[No abstract available]},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
[No abstract available]