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05966 Low energy tribological behavior of carbon-carbon composites
04
By-products
related
to fuels
95lO596Q
H dro en content evaluation in vapour-grown carbon tlbres by !&M!! Madronero, A. and Verdu, M. Carbon, 1995, 33, (3), 247-251. An analysisof hydrogenin vapour-grown carbon fibres by secondary ions mass spectrometry (SIMS) technique allows recognition of the main role of hydrogen in the graphitizing process and mechanical properties. It is known that VGCF have duplex structure, consisting of an inner core and an outer coating. From the SIMS analysis, it is proven that the hydrogen content of the core is greater than in the coating. It is also known that the strength of a-C:H materials increases with the hydrogen content. So, the duplex structure of vapour-grown carbon fibres is really a hard and strong core with a sheath of softer carbonaceous material. 95lO595l Hydrogen control of carbon deposit morphology Nolan, P. E. et al., Carbon, 1995, 33, (l), 79-85. Carbon deposit mo holo y during catal)iic disprQportionation of CO is dependent on a num‘g er of variables. Hydrogen has a significant effect on the form of carbon deposited. It is proposed that the effect of hydrogen is to cause (or allow) open forms of carbon such as filaments to be produced. Hydrogen atoms serve to satisfy valences at the free edges of graphite planes. Without hydrogen, carbon will deposit in closed forms such as ihells and nanotubks. Image analysis of fly ash In the characterlzatlon of 95105962 the shape of the gralns Barrioulet, M. et al., Proc. Mater. Res. Sot. Symp., 1995, 125-133. Flv ash from Dower stations is used as concrete additive to imorove strength and d&ability. Surprisingly, studies of ashes of identical mmeralogical composition from two different places have re orted different results in terms of the rheological properties of the fresR material. The viscosity of the pastes made from these different fly ashes seems to be linked to the proportion of spherical and smooth-shaped grains found in them. The main result roves that the higher the glassy particle content of the fly ash, the more tl!e hydraulic matrix is fluid. 95lOS963
lnhlbltlng effects of hydrogen-donating compounds on 1,&dlphenylpropane thermolysls Wei, X. et al., Meitan Zhuanhua, 1995, 18, (l), 67-70. (In Chinese) The study investigated using 1,3-diphenylpropane as a coal model compound, and the effects of several hydrogen-donating compounds on DPP thermolysis. Results show that hydrogen-donating compounds inhibits 1,3diphenylpropane thennolysis. Laboratory preparatlon of sorbents from chars 95105964 Buchtele, J. and Srogl, J. Acta Mont:, Ser. B., 1994, 4, 33-42. Activates (activated-chars) were prepared from low-ash and high-ash brown-coal chars (ash content 6.2 and 14.4%. resnectivelv1 bv oartial pasification. The specific surface area of 427 m*/g a‘nd the &diie’adsorpson number of 473 mg I/g of the activate qualify the activates to be used as cheap industrial sorbents.
95105966
Manufacture of mesophase pitch ultrafine particles bv dlsoerslna In solvents Kbdami, M. id Pponda, H. (Assigned to) Kogyo Gijutsuin, JAP. Pat.
JP.07.26.269.
Jan. 1995.
The ,r&ess .camprises dissolution of mesophase pitch in solvents and dropping the solutions into nonsolvents of mesophase pitch for dispersing. The solvents may be aromatic hyrocarbons, N-containing heterocyclic compounds, and/or their partial hydrides. 95/05969 Manufacture of pitch for carbon products Yamamoto, I. et al., (Assigned to) Mitsubishi Kagaku q JAP. Pat. JP.07.41.770. Feb. 1995. The &c&s ior the manufacture of pitch for carbon products is carried out by adding rous inor?anics with 2-50 urn average particle size into raw pitch to aPlust viscosity to less than 200 P followed by removing the morganics. The resulting pitch is suitable for carbon products, e.g. carbon fibres and needle coke. 95/05970 Mechanlcal propsrtles of sorbents from brown coal Straka, P. and Brozova, Z. Acta Mont., Ser. B., 1994, 4, 65-72. The mechanical properties of sorbents from brown coal from the North Bohemian Brown Coal Basin were evaluated. QSlO5971 Mechanisms and molecular dynamics of successlve solvolytlc extractlon In simple and thermochemical dlssoclatlve sequential extractlons under amblent pressure condltlons and role of molecular entanglements and dlsaggregatlons Sharma,D. K. Fuel Sci. Technol. Int., 1995, 13, (6), 727-760. Assam coal was subjected to solvent extraction stubiks using 40 solvents belonging to different class, group and functionality. B.p. of a solventwas found to have no relation with extractability of coal ai atmospheric pressure, excepting within the same class, group and functionality of solvents. Points out that B.p should not be used for classifying the coal extractability, rather chemical nature of solvent should be used. Cetene (high boiling alpha-olefin), anthracene oi!, liquid paraffin and ethylenediamine were found to give good extractIon yields for Assam coal. Successive extraction of coal was possible only using anthracene oil or ethylenediamine. 95/05972 The mlcroscoplc structure of char and of activated char from brown coal Sykorova,I. andCermak,I. Acta Mont. Ser. B., 1994, 4, 43-54. Discusses the porous structure of both chars and activated chars from brown coal (North Bohemian Brown Coal Basin) which is affected by the content of attrinite, ulminite, and densinite, the degree of their gelation, and the composition and bonding of the mineral matters, especially the clay minerals.
Llmltlng of SO, and NO, emlsslons In worldwlde coal-power productlon Ellison, W. Radiat. Phys. Chem., 1995, 45, (a), 1003-1011. The paper discusses SO and NO, emission regulation and available technologies for control an (f removal of these stack pollutants in coal firing. Reviews the logistics and trends in worldwide supply and use of diverse available steam coal resources in relation to the need: environmentally, for continuing restraint and reduction in sulphurous emissions.
95lO5973 Mlcrostructural as ects of zeollte formatlon In alkali activated cements containPng hlgh levels of fly ash Brough,A. R. et al., Proc. Mater. Res. Sot. Symp., 1995, 199-208. Discusses wasteforms made by reaction at elevated temperature of a highly alkali simulated low-level nuclear waste solution, having high sodium ion concentration, with a cementitious blend high in fly ash. Significant formation of Na-PI zeolite and of a sodalite occurred. The time evolution of the crystalline phases over the first 28 days is reported for both adiabatic and isothermal curing, and the role of these phases in microstructure development.
Low energy trlbologlcal behavior of carbon-carbon 95105966 composites Chen, J. D. and Ju, C. P. Carbon, 1995, 33, (l), 57-62. The present study compares low energy tribological behaviour among five different carbon-carbon corn osites. Results indicate that all composites had steady-state friction coef 8.lclents case to 0.2, except for ‘TL’which had a much larger initial friction ak (up to 0.6) and higher average friction coefficient (nearly 0.3). For a p” I composites, a flat and smooth self-lubricative debris film was generated on the worn surfaces after sliding for a few meters. For the present carbon-carbon composites, the development of a steady-state friction coefficient value generally occurred earlier than the development of a steady-state wear rate.
Mlneraloglcal transformations and mlcrostructure 95lQ5974 after disposal of cementltlous advanced coal technology byproducUl McCarthy, G. J. et a& Proc. Mater. Res. Sot. Symp., 1995, 179-190. Byproducts from two advanced coal technologies, fluidized bed combustion and limestone injection multistage burner, were found to be cementitious when mixed with water and compacted. However, exposure to natural conditions in test cells resulted in losses of strength and increases in permeability over a period of years. Changes in mineralogy and microstructure with time in recovered core samples have been characterized by powder X-ray diffraction.
95105967 Manufacture of high-strength, water-resls1ant bulldlng materlals uslng brown-coal fly ashes and coal fly ashes Werner. B. et al.. (Assiened to) MPA Labor fuer Materiakvuefuna undAnalysi GmbH, &k. O$en. Dk.4,4,335,642, Apr. 1995. ’ . The recess comprises mixing a mixture consisting of brown-coal fly ashes 5-9. I and coal fly ashes 0.2-5 with water 2-6 wt parts (based on 10 wt. parts dry material), and completing the mixture for building material manufacture.
95105975 Model laboratory unit for the preparatlon of chars Buchtele, J. and Srogl, J. Acta Mont., Ser. E., 1994, 4, 21-32. Chars from two brown-coal samples from the North-Bohemian brown-coal basin were prepared in a laboratory carbonization unit. Standard carbonization conditions were applied to 6-7 kg of coal, grain size 4-10 mm, and the balance of products was evaluated. The maximum yield of 70-80% of char was obtained from the coal having grain size 4-8 mm. Better properties were found in the high-ash char. The char is qualified for the application as a cheap industrial sorbent.
95/05965
424
Fuel and Energy Abstracts November 1995
By-products
related
to fuels
95lO596Q
H dro en content evaluation in vapour-grown carbon tlbres by !&M!! Madronero, A. and Verdu, M. Carbon, 1995, 33, (3), 247-251. An analysisof hydrogenin vapour-grown carbon fibres by secondary ions mass spectrometry (SIMS) technique allows recognition of the main role of hydrogen in the graphitizing process and mechanical properties. It is known that VGCF have duplex structure, consisting of an inner core and an outer coating. From the SIMS analysis, it is proven that the hydrogen content of the core is greater than in the coating. It is also known that the strength of a-C:H materials increases with the hydrogen content. So, the duplex structure of vapour-grown carbon fibres is really a hard and strong core with a sheath of softer carbonaceous material. 95lO595l Hydrogen control of carbon deposit morphology Nolan, P. E. et al., Carbon, 1995, 33, (l), 79-85. Carbon deposit mo holo y during catal)iic disprQportionation of CO is dependent on a num‘g er of variables. Hydrogen has a significant effect on the form of carbon deposited. It is proposed that the effect of hydrogen is to cause (or allow) open forms of carbon such as filaments to be produced. Hydrogen atoms serve to satisfy valences at the free edges of graphite planes. Without hydrogen, carbon will deposit in closed forms such as ihells and nanotubks. Image analysis of fly ash In the characterlzatlon of 95105962 the shape of the gralns Barrioulet, M. et al., Proc. Mater. Res. Sot. Symp., 1995, 125-133. Flv ash from Dower stations is used as concrete additive to imorove strength and d&ability. Surprisingly, studies of ashes of identical mmeralogical composition from two different places have re orted different results in terms of the rheological properties of the fresR material. The viscosity of the pastes made from these different fly ashes seems to be linked to the proportion of spherical and smooth-shaped grains found in them. The main result roves that the higher the glassy particle content of the fly ash, the more tl!e hydraulic matrix is fluid. 95lOS963
lnhlbltlng effects of hydrogen-donating compounds on 1,&dlphenylpropane thermolysls Wei, X. et al., Meitan Zhuanhua, 1995, 18, (l), 67-70. (In Chinese) The study investigated using 1,3-diphenylpropane as a coal model compound, and the effects of several hydrogen-donating compounds on DPP thermolysis. Results show that hydrogen-donating compounds inhibits 1,3diphenylpropane thennolysis. Laboratory preparatlon of sorbents from chars 95105964 Buchtele, J. and Srogl, J. Acta Mont:, Ser. B., 1994, 4, 33-42. Activates (activated-chars) were prepared from low-ash and high-ash brown-coal chars (ash content 6.2 and 14.4%. resnectivelv1 bv oartial pasification. The specific surface area of 427 m*/g a‘nd the &diie’adsorpson number of 473 mg I/g of the activate qualify the activates to be used as cheap industrial sorbents.
95105966
Manufacture of mesophase pitch ultrafine particles bv dlsoerslna In solvents Kbdami, M. id Pponda, H. (Assigned to) Kogyo Gijutsuin, JAP. Pat.
JP.07.26.269.
Jan. 1995.
The ,r&ess .camprises dissolution of mesophase pitch in solvents and dropping the solutions into nonsolvents of mesophase pitch for dispersing. The solvents may be aromatic hyrocarbons, N-containing heterocyclic compounds, and/or their partial hydrides. 95/05969 Manufacture of pitch for carbon products Yamamoto, I. et al., (Assigned to) Mitsubishi Kagaku q JAP. Pat. JP.07.41.770. Feb. 1995. The &c&s ior the manufacture of pitch for carbon products is carried out by adding rous inor?anics with 2-50 urn average particle size into raw pitch to aPlust viscosity to less than 200 P followed by removing the morganics. The resulting pitch is suitable for carbon products, e.g. carbon fibres and needle coke. 95/05970 Mechanlcal propsrtles of sorbents from brown coal Straka, P. and Brozova, Z. Acta Mont., Ser. B., 1994, 4, 65-72. The mechanical properties of sorbents from brown coal from the North Bohemian Brown Coal Basin were evaluated. QSlO5971 Mechanisms and molecular dynamics of successlve solvolytlc extractlon In simple and thermochemical dlssoclatlve sequential extractlons under amblent pressure condltlons and role of molecular entanglements and dlsaggregatlons Sharma,D. K. Fuel Sci. Technol. Int., 1995, 13, (6), 727-760. Assam coal was subjected to solvent extraction stubiks using 40 solvents belonging to different class, group and functionality. B.p. of a solventwas found to have no relation with extractability of coal ai atmospheric pressure, excepting within the same class, group and functionality of solvents. Points out that B.p should not be used for classifying the coal extractability, rather chemical nature of solvent should be used. Cetene (high boiling alpha-olefin), anthracene oi!, liquid paraffin and ethylenediamine were found to give good extractIon yields for Assam coal. Successive extraction of coal was possible only using anthracene oil or ethylenediamine. 95/05972 The mlcroscoplc structure of char and of activated char from brown coal Sykorova,I. andCermak,I. Acta Mont. Ser. B., 1994, 4, 43-54. Discusses the porous structure of both chars and activated chars from brown coal (North Bohemian Brown Coal Basin) which is affected by the content of attrinite, ulminite, and densinite, the degree of their gelation, and the composition and bonding of the mineral matters, especially the clay minerals.
Llmltlng of SO, and NO, emlsslons In worldwlde coal-power productlon Ellison, W. Radiat. Phys. Chem., 1995, 45, (a), 1003-1011. The paper discusses SO and NO, emission regulation and available technologies for control an (f removal of these stack pollutants in coal firing. Reviews the logistics and trends in worldwide supply and use of diverse available steam coal resources in relation to the need: environmentally, for continuing restraint and reduction in sulphurous emissions.
95lO5973 Mlcrostructural as ects of zeollte formatlon In alkali activated cements containPng hlgh levels of fly ash Brough,A. R. et al., Proc. Mater. Res. Sot. Symp., 1995, 199-208. Discusses wasteforms made by reaction at elevated temperature of a highly alkali simulated low-level nuclear waste solution, having high sodium ion concentration, with a cementitious blend high in fly ash. Significant formation of Na-PI zeolite and of a sodalite occurred. The time evolution of the crystalline phases over the first 28 days is reported for both adiabatic and isothermal curing, and the role of these phases in microstructure development.
Low energy trlbologlcal behavior of carbon-carbon 95105966 composites Chen, J. D. and Ju, C. P. Carbon, 1995, 33, (l), 57-62. The present study compares low energy tribological behaviour among five different carbon-carbon corn osites. Results indicate that all composites had steady-state friction coef 8.lclents case to 0.2, except for ‘TL’which had a much larger initial friction ak (up to 0.6) and higher average friction coefficient (nearly 0.3). For a p” I composites, a flat and smooth self-lubricative debris film was generated on the worn surfaces after sliding for a few meters. For the present carbon-carbon composites, the development of a steady-state friction coefficient value generally occurred earlier than the development of a steady-state wear rate.
Mlneraloglcal transformations and mlcrostructure 95lQ5974 after disposal of cementltlous advanced coal technology byproducUl McCarthy, G. J. et a& Proc. Mater. Res. Sot. Symp., 1995, 179-190. Byproducts from two advanced coal technologies, fluidized bed combustion and limestone injection multistage burner, were found to be cementitious when mixed with water and compacted. However, exposure to natural conditions in test cells resulted in losses of strength and increases in permeability over a period of years. Changes in mineralogy and microstructure with time in recovered core samples have been characterized by powder X-ray diffraction.
95105967 Manufacture of high-strength, water-resls1ant bulldlng materlals uslng brown-coal fly ashes and coal fly ashes Werner. B. et al.. (Assiened to) MPA Labor fuer Materiakvuefuna undAnalysi GmbH, &k. O$en. Dk.4,4,335,642, Apr. 1995. ’ . The recess comprises mixing a mixture consisting of brown-coal fly ashes 5-9. I and coal fly ashes 0.2-5 with water 2-6 wt parts (based on 10 wt. parts dry material), and completing the mixture for building material manufacture.
95105975 Model laboratory unit for the preparatlon of chars Buchtele, J. and Srogl, J. Acta Mont., Ser. E., 1994, 4, 21-32. Chars from two brown-coal samples from the North-Bohemian brown-coal basin were prepared in a laboratory carbonization unit. Standard carbonization conditions were applied to 6-7 kg of coal, grain size 4-10 mm, and the balance of products was evaluated. The maximum yield of 70-80% of char was obtained from the coal having grain size 4-8 mm. Better properties were found in the high-ash char. The char is qualified for the application as a cheap industrial sorbent.
95/05965
424
Fuel and Energy Abstracts November 1995