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04328 Optical energy gap and below gap optical absorption of fullerene films measured by the constant photocurrent method and photothermal deflection spectroscopy
16
Fuel science and technology
Kinematics of the quasi-coherent vertical structure 95104317 in near-wall turbulence Kasagi, N. er al., Hear & Fluid Flow, Feb. 1995, 16, (l), 2-10. Near-wall turbulence structures in a direct numerical simulation database of turbulent channel flow were investigatd by using a three-dimensional (3D) computer graphics software tool. Several candidate methods to detect near-wall vertical structures were tested. They were based on instantaneous flow properties such as pressure, vorticity, enstrophy, dissipation rate, and the second invariant of deformation tensor. Among them, the low-pressure regions and those of negative second invariant of the deformation tensor corresponded well to the cores of vertical fluid motion. The spatial distribution of each term in the Reynolds stress transport equations was also examined in the instantaneous field to explore the role of vertical structures in production and destruction of the Reynolds stresses.
Laminar flow developlng heat transfer in circular 95104319 sector ducts with HI and H2, boundary conditions Chung, B. T. and Hsia, k. P. Hear Transfer Engng., Oct.-Dec. 1994, 15, (4). 56-65. Hydrodynamically developed and thermally developing laminar incompressible forced-convective flow in ducts containing’ twisted-tape inserts is analyzed. The flow is subjected to either uniform temperature or uniform heat flux on the curved duct surface, and the straight duct surfaces are insulated. The heat input into the fluid is only from the curved duct surface and is uniform axially. The thermal properties are assumed constant; the axial conduction and viscous dissipation are negligibly small. Numerical calculations of the temperature field and Nusselt number march forward axially in the thermal entrance region.
Liquid chromatographic procedure and apparatus 95lO43 19 for separation and qualitative and quantitative determination of polycyclic aromatic hydrocarbons in hydrocarbon-containing mixtures Zobel. H. et al.. lAssiened to) VVE-Instirur fuer Technische Chemie und Vmw&chutr ‘GmbH - privaie Forschungseinrichrung, GER. Offen. DE.4,312,925, Oct. 1994.
95/04320 Measurement and detectlon of radlatlon - Second edltlon Tsoulfanidis, N. Taylor & Francis, 1900 Frost Road, Suire 101, Bristol, PA.19007, USA, 1995, 614 pp. While retaining the approach and format of the original, the second edition of this outstanding textbook addresses the fundamentals of nuclear radiation counting in a clear, easy-to-read way. The text, intended for undergraduate and graduate level, assumes a basic knowledge of calculus and differential equations and of atomic nuclear physics. In laboratories, where atomic and nuclear radiation is used, engineers, scientists, and technicians will also find this a useful reference.
95104321 Measurement of -OH groups In coals of dlfferent rank using mlcrowave methodology, and the development of quantltatlve solld state n.m.r. methods for in situ analysls Monsef-Mirzai, P. er al., Fuel, May 1995, 74, (5), 674-683. Experiments with both model compounds (substituted phenols) and with 11 coals (9 British and 2 American) have established that microwave heating will greatly accelerate silylation reactions of the phenolic -OH groups, e.g. for Creswell coal complete silylation of -OH groups occurs in 35 min in the microwave oven, whereas 24h is required using a bench reflux technique. Microwave reaction times for coals vary from 35 min to 3h for more dense coals such as Cortonwood. These observations have allowed the development of a ‘one pot’ silylation of coal, followed by an in situ analysis of the added Me,Si- groups by quantitative *?ii magic angle spinning nuclear magnetic resonance spectroscopy.
Mechanism of sulfur chemllumlnescent emlsslon 95lQ4322 In pulsed flames Cheskis, S. Comburrion & Flume, Mar. 1995, 100, (4), 550-558. Time-resolved light emission from an atmospheric pressure hydrogen/air pulsed propagated flame doped with a small concentration of SO, was measured. The main idea of the pulsed flame approach is to exchange the usual continuous flame with an unstable pulsed propagating flame where flashback occurs repetitively. The use of pulsed flame instead of the usual continuous one allows the replacement space measurements by timeresolved experiments. This approach is very successful in constructing a pulsed flame photometer molecular detector. The emission from electronically excited sulphur molecules is dramatically delayed after the short background pulse associated with OH radical emission.
Mlxed convectlon heat transfer from 8 vertical plate 95104323 to non-Newtonlan fluids Wang, T. Y. Heat & Fluid Flow, Feb. 1995, 16, (l), 56-61. The nonsimilar boundary-layer analysis of steady laminar mixed-convection heat transfer between a vertical plate and non-Newtonian fluids is extended and unified.
(fundamental
science, analysis, instrumentation)
95104324 Molecular characterization of vitrlnite maturation as revealed by flash pyrolysis methods Veld, H. et al., ACS Symp. Ser., 1994, (570), 149-160. Curie-point pyrolysis - gas chromatography analyses were performed on four vltrinite concentrations of maturity levels from 0.96 to 1.93% Rmax. Analyses were carried out on ‘thermal extractions’ obtained at a Curietemperature of 358” and on pyrolyzates obtained at a Curie-temperature of 770 . The relative concentrations of alkylphenols and alkylnaphthalenes decrease with increasing maturity. Alkylbenzenes are prominent pyrolysis products throughout the maturity interval investigated. A significant increase in the relative concentration of alkylphenanthrenes and alkylbiphenyls with increasing maturity is noted. 95104325 Need for standardization of vltrinite reflectance measurements De Vanney, K. F. and Stanton, R. W. ACS Symp. Ser., 1994, (570), 26-38. Discusses the results of interlaboratory comparisons of vitrinite reflectance measurements which indicate additional need for standardizing: (1) the type of vitrinite to be measured, (2) the details of the measuring technique, and (3) the optical equipment used. Vitrinite reflectance is a critical characterization parameter that is widely used in geological studies, exploration, classification, extraction, and utilization of fossil fuels. On the limitations of the Brlnkman-Forchhelmer95104326 extended Darcy equation Vafai, K. and Kim, S. J. Hear & Fluid Flow, Feb. 1995, 16, (l), 11-15. In this work, several philosophical points with respect to the momentum equation in a porous medium are analyzed. The authors show that several erroneous/irrelevant issues were put forward in previous work. A porous medium/clear fluid interface is best dealt with by the Brinkman-Forchheimer-extended Darcy formulation and the continuity of velocities and stresses at the interface. The effect of porosity variation is not required for a high-porosity medium but should be considered for a dense porous medium. On the normal detonatlon shock veloclty-curvature 95104327 relationship for materlals with large actlvatlon energy ;;;:5Jigand Stewart, D. S. Combusrion & Flame, Mar. 1995, 100, (4), The authors derive the normal detonation shock velocity-curvature relation for a near-Chapman-Jouguet detonation, for an explosive material with Arrhenius kinetics and a large activation energy. Large activation energy asym totics are used to develop an ex licit exponential formula relating the s I!ock curvature K to the normal Betonatlon shock speed D,. In this case, the D,-K relation is multivalued and has a turning point with a critical curvature Kc, such that for k>K,, the possibility of detonation extinction arises. The asymptotic formula IS in excellent agreement with the exact solution found by a numerical shooting procedure. 95104326 Optical energy gap and below gap optlcal absorp tlon of fullerene films measured by the constant photocurrent method and photothermal deflectlon spectroscopy Hasegawa, S. et al., Fullerene Science & Technol., 1995, 3, (3), 313-325. Discusses how the CPM spectra of fullerene films was measured to obtain the below gap absorption. The optical energy gap E, was obtained by using the Taut’s plots, E, did not change greatly with intercalated impurities. The absorption due to intercalated impurities was found below 1.6eV. 95104329 Preparation and air-separatlon propertles of membrane blends of low-molecular-welght llquld crystals wlth cellulose derlvatlves Huang, M. R. and Li, X. G. Gas Separation & Purification, 1995, 9, (2), 87-92. Four kinds of low-molecular-weight liquid crystals (LCs) (Cholesteryl oleyl carbonate (COC), the benzoate-containing mixture LC DYC, pheptyl-p’-cyanobiphenyl (7CB), p-pentylphenol-p’-methoxybenzoate (5PMB) and four cellulose derivatives (ethyl cellulose (EC), celluloe diacetate, cellulose triacetate, cellulose nitrate) were used to prepare blend membranes of thickness 13-45 microns by a solution casting technique. Presence of remnant cell structure In vltrlnlte and 95104330 Its Influence on reflectance propertles Bensley, D. F. and Crelling, J. C. ACS Symp. Ser., 1994, (570), 39-51. The paper discusses the interpretation of reflectance which is dependent in part upon an assessment of the reflectance distribution. In general, as the distribution of reflectance values broaden, displaying an increase in standard deviation, the analytical interpretation becomes increasingly difficult. A pyrolysis-gas chromatographylmass spectrome95104331 try study on coals Nali, M. et al., J. Anal. Appl. Pyrolysis, 1994, 29, (l), 15-23. Various coals, including the complete set of Argonne Premium Coal samples, were characterized using pyrolysis-gas chromatography-mass spectrometry. The addition of the gas chromatography step to the analysis significantly improved the separation, identification, and quantitation of volatile pyrolysis products. The results were independent of the storage condition of the sample.
Fuel and Energy Abstracts
July 1995
303
Fuel science and technology
Kinematics of the quasi-coherent vertical structure 95104317 in near-wall turbulence Kasagi, N. er al., Hear & Fluid Flow, Feb. 1995, 16, (l), 2-10. Near-wall turbulence structures in a direct numerical simulation database of turbulent channel flow were investigatd by using a three-dimensional (3D) computer graphics software tool. Several candidate methods to detect near-wall vertical structures were tested. They were based on instantaneous flow properties such as pressure, vorticity, enstrophy, dissipation rate, and the second invariant of deformation tensor. Among them, the low-pressure regions and those of negative second invariant of the deformation tensor corresponded well to the cores of vertical fluid motion. The spatial distribution of each term in the Reynolds stress transport equations was also examined in the instantaneous field to explore the role of vertical structures in production and destruction of the Reynolds stresses.
Laminar flow developlng heat transfer in circular 95104319 sector ducts with HI and H2, boundary conditions Chung, B. T. and Hsia, k. P. Hear Transfer Engng., Oct.-Dec. 1994, 15, (4). 56-65. Hydrodynamically developed and thermally developing laminar incompressible forced-convective flow in ducts containing’ twisted-tape inserts is analyzed. The flow is subjected to either uniform temperature or uniform heat flux on the curved duct surface, and the straight duct surfaces are insulated. The heat input into the fluid is only from the curved duct surface and is uniform axially. The thermal properties are assumed constant; the axial conduction and viscous dissipation are negligibly small. Numerical calculations of the temperature field and Nusselt number march forward axially in the thermal entrance region.
Liquid chromatographic procedure and apparatus 95lO43 19 for separation and qualitative and quantitative determination of polycyclic aromatic hydrocarbons in hydrocarbon-containing mixtures Zobel. H. et al.. lAssiened to) VVE-Instirur fuer Technische Chemie und Vmw&chutr ‘GmbH - privaie Forschungseinrichrung, GER. Offen. DE.4,312,925, Oct. 1994.
95/04320 Measurement and detectlon of radlatlon - Second edltlon Tsoulfanidis, N. Taylor & Francis, 1900 Frost Road, Suire 101, Bristol, PA.19007, USA, 1995, 614 pp. While retaining the approach and format of the original, the second edition of this outstanding textbook addresses the fundamentals of nuclear radiation counting in a clear, easy-to-read way. The text, intended for undergraduate and graduate level, assumes a basic knowledge of calculus and differential equations and of atomic nuclear physics. In laboratories, where atomic and nuclear radiation is used, engineers, scientists, and technicians will also find this a useful reference.
95104321 Measurement of -OH groups In coals of dlfferent rank using mlcrowave methodology, and the development of quantltatlve solld state n.m.r. methods for in situ analysls Monsef-Mirzai, P. er al., Fuel, May 1995, 74, (5), 674-683. Experiments with both model compounds (substituted phenols) and with 11 coals (9 British and 2 American) have established that microwave heating will greatly accelerate silylation reactions of the phenolic -OH groups, e.g. for Creswell coal complete silylation of -OH groups occurs in 35 min in the microwave oven, whereas 24h is required using a bench reflux technique. Microwave reaction times for coals vary from 35 min to 3h for more dense coals such as Cortonwood. These observations have allowed the development of a ‘one pot’ silylation of coal, followed by an in situ analysis of the added Me,Si- groups by quantitative *?ii magic angle spinning nuclear magnetic resonance spectroscopy.
Mechanism of sulfur chemllumlnescent emlsslon 95lQ4322 In pulsed flames Cheskis, S. Comburrion & Flume, Mar. 1995, 100, (4), 550-558. Time-resolved light emission from an atmospheric pressure hydrogen/air pulsed propagated flame doped with a small concentration of SO, was measured. The main idea of the pulsed flame approach is to exchange the usual continuous flame with an unstable pulsed propagating flame where flashback occurs repetitively. The use of pulsed flame instead of the usual continuous one allows the replacement space measurements by timeresolved experiments. This approach is very successful in constructing a pulsed flame photometer molecular detector. The emission from electronically excited sulphur molecules is dramatically delayed after the short background pulse associated with OH radical emission.
Mlxed convectlon heat transfer from 8 vertical plate 95104323 to non-Newtonlan fluids Wang, T. Y. Heat & Fluid Flow, Feb. 1995, 16, (l), 56-61. The nonsimilar boundary-layer analysis of steady laminar mixed-convection heat transfer between a vertical plate and non-Newtonian fluids is extended and unified.
(fundamental
science, analysis, instrumentation)
95104324 Molecular characterization of vitrlnite maturation as revealed by flash pyrolysis methods Veld, H. et al., ACS Symp. Ser., 1994, (570), 149-160. Curie-point pyrolysis - gas chromatography analyses were performed on four vltrinite concentrations of maturity levels from 0.96 to 1.93% Rmax. Analyses were carried out on ‘thermal extractions’ obtained at a Curietemperature of 358” and on pyrolyzates obtained at a Curie-temperature of 770 . The relative concentrations of alkylphenols and alkylnaphthalenes decrease with increasing maturity. Alkylbenzenes are prominent pyrolysis products throughout the maturity interval investigated. A significant increase in the relative concentration of alkylphenanthrenes and alkylbiphenyls with increasing maturity is noted. 95104325 Need for standardization of vltrinite reflectance measurements De Vanney, K. F. and Stanton, R. W. ACS Symp. Ser., 1994, (570), 26-38. Discusses the results of interlaboratory comparisons of vitrinite reflectance measurements which indicate additional need for standardizing: (1) the type of vitrinite to be measured, (2) the details of the measuring technique, and (3) the optical equipment used. Vitrinite reflectance is a critical characterization parameter that is widely used in geological studies, exploration, classification, extraction, and utilization of fossil fuels. On the limitations of the Brlnkman-Forchhelmer95104326 extended Darcy equation Vafai, K. and Kim, S. J. Hear & Fluid Flow, Feb. 1995, 16, (l), 11-15. In this work, several philosophical points with respect to the momentum equation in a porous medium are analyzed. The authors show that several erroneous/irrelevant issues were put forward in previous work. A porous medium/clear fluid interface is best dealt with by the Brinkman-Forchheimer-extended Darcy formulation and the continuity of velocities and stresses at the interface. The effect of porosity variation is not required for a high-porosity medium but should be considered for a dense porous medium. On the normal detonatlon shock veloclty-curvature 95104327 relationship for materlals with large actlvatlon energy ;;;:5Jigand Stewart, D. S. Combusrion & Flame, Mar. 1995, 100, (4), The authors derive the normal detonation shock velocity-curvature relation for a near-Chapman-Jouguet detonation, for an explosive material with Arrhenius kinetics and a large activation energy. Large activation energy asym totics are used to develop an ex licit exponential formula relating the s I!ock curvature K to the normal Betonatlon shock speed D,. In this case, the D,-K relation is multivalued and has a turning point with a critical curvature Kc, such that for k>K,, the possibility of detonation extinction arises. The asymptotic formula IS in excellent agreement with the exact solution found by a numerical shooting procedure. 95104326 Optical energy gap and below gap optlcal absorp tlon of fullerene films measured by the constant photocurrent method and photothermal deflectlon spectroscopy Hasegawa, S. et al., Fullerene Science & Technol., 1995, 3, (3), 313-325. Discusses how the CPM spectra of fullerene films was measured to obtain the below gap absorption. The optical energy gap E, was obtained by using the Taut’s plots, E, did not change greatly with intercalated impurities. The absorption due to intercalated impurities was found below 1.6eV. 95104329 Preparation and air-separatlon propertles of membrane blends of low-molecular-welght llquld crystals wlth cellulose derlvatlves Huang, M. R. and Li, X. G. Gas Separation & Purification, 1995, 9, (2), 87-92. Four kinds of low-molecular-weight liquid crystals (LCs) (Cholesteryl oleyl carbonate (COC), the benzoate-containing mixture LC DYC, pheptyl-p’-cyanobiphenyl (7CB), p-pentylphenol-p’-methoxybenzoate (5PMB) and four cellulose derivatives (ethyl cellulose (EC), celluloe diacetate, cellulose triacetate, cellulose nitrate) were used to prepare blend membranes of thickness 13-45 microns by a solution casting technique. Presence of remnant cell structure In vltrlnlte and 95104330 Its Influence on reflectance propertles Bensley, D. F. and Crelling, J. C. ACS Symp. Ser., 1994, (570), 39-51. The paper discusses the interpretation of reflectance which is dependent in part upon an assessment of the reflectance distribution. In general, as the distribution of reflectance values broaden, displaying an increase in standard deviation, the analytical interpretation becomes increasingly difficult. A pyrolysis-gas chromatographylmass spectrome95104331 try study on coals Nali, M. et al., J. Anal. Appl. Pyrolysis, 1994, 29, (l), 15-23. Various coals, including the complete set of Argonne Premium Coal samples, were characterized using pyrolysis-gas chromatography-mass spectrometry. The addition of the gas chromatography step to the analysis significantly improved the separation, identification, and quantitation of volatile pyrolysis products. The results were independent of the storage condition of the sample.
Fuel and Energy Abstracts
July 1995
303