A binary alloy consisting of poly（phenylene-sulfide） （PPS）/poly（ethylene terephthalate-co-l,4- cyclohexanedimethanol） （PETG） was prepared by the melt blending technology using a twin-screw extruder. The morpho...A binary alloy consisting of poly（phenylene-sulfide） （PPS）/poly（ethylene terephthalate-co-l,4- cyclohexanedimethanol） （PETG） was prepared by the melt blending technology using a twin-screw extruder. The morphology and crystallization behavior of the alloy material were investigated by means of SEM, POM and DSC. The SEM study of the alloy samples revealed that PPS and PETG comprised an incompatible system and the interface structure of two phases could be observed distinctly when the composition of the binary alloy was being changed. The POM results had revealed that incorporation of PETG into PPS could lead to formation of larger spherulite crystals in the course of PPS crystallization, but small and grainy spherulite crystals appeared with further increase in the PETG concentration. The DSC analyses revealed that addition of PETG to the alloy composition could shift the PPS crystallization temperature towards the high-temperature region.展开更多
It is highly important to investigate relationship between coal characteristics and methane adsorption on coal in the fields of coalbed methane recovery. Based on data examination of coal quality indexes collected fro...It is highly important to investigate relationship between coal characteristics and methane adsorption on coal in the fields of coalbed methane recovery. Based on data examination of coal quality indexes collected from the literatures, regression equations for Langmuir adsorption constants, VL or VLIPL, and coal quality indexes for selected coal samples were developed with multiple linear regression of SPSS software according to the degree of coal metamorphosis. The regression equations built were tested with data collected from some literatures, and the influences of coal quality indexes on CH4 adsorption on coals were studied with investigation of regression equations, and the reasons of low accuracy to Langmuir constants calculated with regression equation for a few coal samples were investigated. The results show that the regression equations can be employed to predict Langmuir constants for methane adsorption isotherms on coals obtained using volumetric gas adsorption experiments, which are conducted at 30 ℃ on a wet or dried coal samples with less than 30% ash content in coal. The influence of same coal quality index with various coal rank or influence of various coal quality indexes for same coal rank on CH4 adsorption is not consistent. The regression equations have different accuracy to different coal rank, in which the VL equations supply better prediction accuracy for anthracite and higher prediction error for lower metamorphosis coal, and the PL prediction error with VL and VL/PL equations is lower to bituminous coal and higher to anthracite.展开更多
A two-dimensional numerical mine strata in the vicinity of seam 349 in model of a large （1 000 m× 200 m） section of Iongwall panel 802 in part B of the Murcki Colliery in the Upper Silesian Coal Basin, Poland, ...A two-dimensional numerical mine strata in the vicinity of seam 349 in model of a large （1 000 m× 200 m） section of Iongwall panel 802 in part B of the Murcki Colliery in the Upper Silesian Coal Basin, Poland, was built using the Universal Distinct Element Code UDEC. Longwall extraction of seam 349 with roof caving was simulated in the model over a length of 450 m. Mining-induced changes in displacements, strains and stresses in the mine strata were investigated. Under the assumptions that （1） methane-bearing strata occur 15.6 m beneath seam 349 and include seam 350 and the strata lying beneath, and （2） the methane reservoir pressure is equal to 2 MPa, a fully coupled mechanical hydraulic analysis was performed in which joint conductivity was dependent on the mechanical deformation and, conversely, the mechanical behavior of rock masses was affected by joint fluid pressure. It was shown that migration of methane from coal seams lying beneath the mined seam is possible under conditions where the floor strata deform to a great extent, undergo separation, fracture and break into blocks.展开更多
Experimental investigations were conducted on the process of combustion and explosion vent in a 200 mm (diame- ter)×400 mm (length) vertical cylindrical vessel. When CH4-air mixture gases were used and the vent d...Experimental investigations were conducted on the process of combustion and explosion vent in a 200 mm (diame- ter)×400 mm (length) vertical cylindrical vessel. When CH4-air mixture gases were used and the vent diameter was 55 mm, conditions of Φ (equivalent ratio)=0.8, Φ=1.0 and Φ=1.3 and two ignition positions (at the cylinder center and bottom) were selected. The venting processes and the correlated factors are discussed in this paper.展开更多
Catalytic activities of NiMo/MCM-41 and the mixture of Ni/MCM-41 with H-MCM-41 in cracking used ULO （lubricant oil） have been studied. This work was started by synthesis of aluminosilicate （MCM-41） at ratio of Si/...Catalytic activities of NiMo/MCM-41 and the mixture of Ni/MCM-41 with H-MCM-41 in cracking used ULO （lubricant oil） have been studied. This work was started by synthesis of aluminosilicate （MCM-41） at ratio of Si/AI = 50, using CTAB （cetyltrimethylammonium bromide） as a template, and TMAOH （tetramethylammonium hydroxide） as co-surfactant, where a hydrothermal process at 100 ℃ was conducted for 12 h. Organic compounds were then burned out from the dry solid material by calcination at 540 ℃. Ni/MCM-41 and H-MCM-41 were produced by ion exchange method, followed by reduction and calcination treatments, respectively, while NiMo/MCM-41 was produced by impregnation method followed by calcination. Product of MCM-41 was characterized by XRD （X-ray Diffraction）, Fourier FTIR （transform infra red spectrophotometric）, TEM （transmission electron microscopic） and BET （brunauer-emmet-teller） methods. Performance of the catalytic activities were shown by both of NiMo/MCM-41 and the mixture of 1：1 of H-MCM-41 and Ni/MCM-41 were mixed with the ULO at ratio of 1：200 （w/v） in a stainless steel reactor, then they were heated at 420 ℃. The products of cracking were analyzed using GC-MS （gas chromatography-mass spectrometry）. Results of the work showed that the MCM-41 was successfully synthesized. Using mixture of Ni/MCM-41 and H-MCM-41 catalysts, 56.6% of ULO could be converted to OLP （organic liquid product）. However, using NiMo/MCM-41 catalyst only 28.5% OLP could be produced. GC-MS analyses showed that cracking of the ULO at 420 ~C using NiMo/MCM-41 catalyst gave conversion 4.3% and 8.8% to gasoline like and diesel like fractions, respectively, while using mixture of Ni/MCM-41 and H-MCM-41 catalysts, conversion of 12.2% and 14.8% respectively to gasoline like and diesel like fractions were obtained.展开更多
Well logging technology in coalbed methane （CBM） exploration may develop in two directions： one is the novel well logging methods; the other is the new interpretation methods for the conventional logging data, on w...Well logging technology in coalbed methane （CBM） exploration may develop in two directions： one is the novel well logging methods; the other is the new interpretation methods for the conventional logging data, on which the authors of this paper concentrated mainly. The paper introduced several methods in calculating with well logs such important parameters as porosity, permeability and gas content of CBM reservoir and evaluated their effectiveness. A new method of well logging data interpretation was put forward for coalbed recognition, i.e., the combination of the principal component analysis and the wavelet transform. The authors find that the second principal component （PCA2） contains much more information of coalbed in the coal-bearing series and the reconstruction signal from the detailed wavelet coefficients at level 4 （PCA24） and 5 （PCA25） highlights the signature ofcoalbeds. In terms of the characteristics of CBM reservoir in China, the authors summarized the key points in the application of well logging technique to CBM exploration, and gave a guideline for further related research work.展开更多
A complete mechanism of methane pyrolysis is proposed for chemical vapor infiltration of pyrocarbon with different textures, which contains a detailed homogeneous mechanism for gas reactions and a lumped heterogeneous...A complete mechanism of methane pyrolysis is proposed for chemical vapor infiltration of pyrocarbon with different textures, which contains a detailed homogeneous mechanism for gas reactions and a lumped heterogeneous mechanism for pyrocarbon deposition. This model is easily applied to simulate gas compositions and pyrocarbon deposition in a vertical hot-wall flow reactor in the temperature range of 1,323–1,398 K without any adjusting parameters and presents better results than previous mechanisms. Results have shown that the consumption of methane and the production of hydrogen are well enhanced due to pyrocarbon deposition. Pyrocarbon deposition prevents the continuously increasing of acetylene composition and leads to the reduction in the mole fraction of benzene at long residence times in the gas phase. The carbon growth with active sites on the surface is the controlling mechanism of pyrocarbon deposition. C1 species is the precursor of pyrocarbon deposition at 1,323 K,and the primary source over the whole temperature range. As temperature increases, gas phase becomes more mature and depositions from acetylene, benzene and polyaromatic hydrocarbons become more prevalent. A general pyrocarbon formation mechanism is derived with the specific precursors and illustrates that the maturation of gas compositions is beneficial to forming planar structures with hexagonal rings or pentagon-heptagon pairs, namely, high textured pyrocarbon. The results are in well agreement with experiments.展开更多
The series of 2-（1-（2,4-dibenzhydrylnaphthylimino）ethyl）-6-（1-（arylimino）ethyl）pyridine derivatives and their cobalt chlorides （Col-Co5） were synthesized and fully characterized. The representative complexes...The series of 2-（1-（2,4-dibenzhydrylnaphthylimino）ethyl）-6-（1-（arylimino）ethyl）pyridine derivatives and their cobalt chlorides （Col-Co5） were synthesized and fully characterized. The representative complexes Co2 and Co3 were confirmed by single crystal X-ray diffraction analyses, indicating pseudo-square-pyramidal geometry around the cobalt centre. All cobalt complexes, activated with either methylaluminoxane （MAO） or modified methylaluminoxane （MMAO）, exhibited high activities towards ethylene polymerization, and produced polyethylenes with high molecular weight and highly linear feature as well as unimodal distribution.展开更多
A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneum...A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneumatic microvalve control was proposed. The sample and reagent solutions were synchronously loaded and injected in the chip-based sample injection module instead of multi-step sequential injection by a multiposition valve and a reciprocating pump as in conventional SIA system. The sample and reagent injection volumes were reduced to ca. 1.1 nL. The present system has the advantages of simple structure, fast and convenient operation, low sample and reagent consumption, and high degree of integration and automation. The system operation conditions were optimized using fluorescein as model sample. Its feasibility in biological analysis was preliminarily demonstrated in enzyme inhibition assay.展开更多
文摘A binary alloy consisting of poly（phenylene-sulfide） （PPS）/poly（ethylene terephthalate-co-l,4- cyclohexanedimethanol） （PETG） was prepared by the melt blending technology using a twin-screw extruder. The morphology and crystallization behavior of the alloy material were investigated by means of SEM, POM and DSC. The SEM study of the alloy samples revealed that PPS and PETG comprised an incompatible system and the interface structure of two phases could be observed distinctly when the composition of the binary alloy was being changed. The POM results had revealed that incorporation of PETG into PPS could lead to formation of larger spherulite crystals in the course of PPS crystallization, but small and grainy spherulite crystals appeared with further increase in the PETG concentration. The DSC analyses revealed that addition of PETG to the alloy composition could shift the PPS crystallization temperature towards the high-temperature region.
文摘It is highly important to investigate relationship between coal characteristics and methane adsorption on coal in the fields of coalbed methane recovery. Based on data examination of coal quality indexes collected from the literatures, regression equations for Langmuir adsorption constants, VL or VLIPL, and coal quality indexes for selected coal samples were developed with multiple linear regression of SPSS software according to the degree of coal metamorphosis. The regression equations built were tested with data collected from some literatures, and the influences of coal quality indexes on CH4 adsorption on coals were studied with investigation of regression equations, and the reasons of low accuracy to Langmuir constants calculated with regression equation for a few coal samples were investigated. The results show that the regression equations can be employed to predict Langmuir constants for methane adsorption isotherms on coals obtained using volumetric gas adsorption experiments, which are conducted at 30 ℃ on a wet or dried coal samples with less than 30% ash content in coal. The influence of same coal quality index with various coal rank or influence of various coal quality indexes for same coal rank on CH4 adsorption is not consistent. The regression equations have different accuracy to different coal rank, in which the VL equations supply better prediction accuracy for anthracite and higher prediction error for lower metamorphosis coal, and the PL prediction error with VL and VL/PL equations is lower to bituminous coal and higher to anthracite.
文摘A two-dimensional numerical mine strata in the vicinity of seam 349 in model of a large （1 000 m× 200 m） section of Iongwall panel 802 in part B of the Murcki Colliery in the Upper Silesian Coal Basin, Poland, was built using the Universal Distinct Element Code UDEC. Longwall extraction of seam 349 with roof caving was simulated in the model over a length of 450 m. Mining-induced changes in displacements, strains and stresses in the mine strata were investigated. Under the assumptions that （1） methane-bearing strata occur 15.6 m beneath seam 349 and include seam 350 and the strata lying beneath, and （2） the methane reservoir pressure is equal to 2 MPa, a fully coupled mechanical hydraulic analysis was performed in which joint conductivity was dependent on the mechanical deformation and, conversely, the mechanical behavior of rock masses was affected by joint fluid pressure. It was shown that migration of methane from coal seams lying beneath the mined seam is possible under conditions where the floor strata deform to a great extent, undergo separation, fracture and break into blocks.
基金Project (No. 19832030) supported by the National Natural Science Foundation of China
文摘Experimental investigations were conducted on the process of combustion and explosion vent in a 200 mm (diame- ter)×400 mm (length) vertical cylindrical vessel. When CH4-air mixture gases were used and the vent diameter was 55 mm, conditions of Φ (equivalent ratio)=0.8, Φ=1.0 and Φ=1.3 and two ignition positions (at the cylinder center and bottom) were selected. The venting processes and the correlated factors are discussed in this paper.
文摘Catalytic activities of NiMo/MCM-41 and the mixture of Ni/MCM-41 with H-MCM-41 in cracking used ULO （lubricant oil） have been studied. This work was started by synthesis of aluminosilicate （MCM-41） at ratio of Si/AI = 50, using CTAB （cetyltrimethylammonium bromide） as a template, and TMAOH （tetramethylammonium hydroxide） as co-surfactant, where a hydrothermal process at 100 ℃ was conducted for 12 h. Organic compounds were then burned out from the dry solid material by calcination at 540 ℃. Ni/MCM-41 and H-MCM-41 were produced by ion exchange method, followed by reduction and calcination treatments, respectively, while NiMo/MCM-41 was produced by impregnation method followed by calcination. Product of MCM-41 was characterized by XRD （X-ray Diffraction）, Fourier FTIR （transform infra red spectrophotometric）, TEM （transmission electron microscopic） and BET （brunauer-emmet-teller） methods. Performance of the catalytic activities were shown by both of NiMo/MCM-41 and the mixture of 1：1 of H-MCM-41 and Ni/MCM-41 were mixed with the ULO at ratio of 1：200 （w/v） in a stainless steel reactor, then they were heated at 420 ℃. The products of cracking were analyzed using GC-MS （gas chromatography-mass spectrometry）. Results of the work showed that the MCM-41 was successfully synthesized. Using mixture of Ni/MCM-41 and H-MCM-41 catalysts, 56.6% of ULO could be converted to OLP （organic liquid product）. However, using NiMo/MCM-41 catalyst only 28.5% OLP could be produced. GC-MS analyses showed that cracking of the ULO at 420 ~C using NiMo/MCM-41 catalyst gave conversion 4.3% and 8.8% to gasoline like and diesel like fractions, respectively, while using mixture of Ni/MCM-41 and H-MCM-41 catalysts, conversion of 12.2% and 14.8% respectively to gasoline like and diesel like fractions were obtained.
基金This work was supported by Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry （2006331）, China Postdoctoral Science Foundation （20070411106） and Open Fund of Key Laboratory of Depositional Mineralization ＆ Sedimentary Mineral, Shandong Province （DMSM200802）.
文摘Well logging technology in coalbed methane （CBM） exploration may develop in two directions： one is the novel well logging methods; the other is the new interpretation methods for the conventional logging data, on which the authors of this paper concentrated mainly. The paper introduced several methods in calculating with well logs such important parameters as porosity, permeability and gas content of CBM reservoir and evaluated their effectiveness. A new method of well logging data interpretation was put forward for coalbed recognition, i.e., the combination of the principal component analysis and the wavelet transform. The authors find that the second principal component （PCA2） contains much more information of coalbed in the coal-bearing series and the reconstruction signal from the detailed wavelet coefficients at level 4 （PCA24） and 5 （PCA25） highlights the signature ofcoalbeds. In terms of the characteristics of CBM reservoir in China, the authors summarized the key points in the application of well logging technique to CBM exploration, and gave a guideline for further related research work.
基金supported by the National Natural Science Foundation of China (51521061 and 51472203)the "111" Project (B08040)the Research Fund of State Key Laboratory of Solidification Processing (NWPU),China (142-TZ-2016)
文摘A complete mechanism of methane pyrolysis is proposed for chemical vapor infiltration of pyrocarbon with different textures, which contains a detailed homogeneous mechanism for gas reactions and a lumped heterogeneous mechanism for pyrocarbon deposition. This model is easily applied to simulate gas compositions and pyrocarbon deposition in a vertical hot-wall flow reactor in the temperature range of 1,323–1,398 K without any adjusting parameters and presents better results than previous mechanisms. Results have shown that the consumption of methane and the production of hydrogen are well enhanced due to pyrocarbon deposition. Pyrocarbon deposition prevents the continuously increasing of acetylene composition and leads to the reduction in the mole fraction of benzene at long residence times in the gas phase. The carbon growth with active sites on the surface is the controlling mechanism of pyrocarbon deposition. C1 species is the precursor of pyrocarbon deposition at 1,323 K,and the primary source over the whole temperature range. As temperature increases, gas phase becomes more mature and depositions from acetylene, benzene and polyaromatic hydrocarbons become more prevalent. A general pyrocarbon formation mechanism is derived with the specific precursors and illustrates that the maturation of gas compositions is beneficial to forming planar structures with hexagonal rings or pentagon-heptagon pairs, namely, high textured pyrocarbon. The results are in well agreement with experiments.
基金supported by the National Natural Science Foundation of China (U1362204, 51473170, 21572085)
文摘The series of 2-（1-（2,4-dibenzhydrylnaphthylimino）ethyl）-6-（1-（arylimino）ethyl）pyridine derivatives and their cobalt chlorides （Col-Co5） were synthesized and fully characterized. The representative complexes Co2 and Co3 were confirmed by single crystal X-ray diffraction analyses, indicating pseudo-square-pyramidal geometry around the cobalt centre. All cobalt complexes, activated with either methylaluminoxane （MAO） or modified methylaluminoxane （MMAO）, exhibited high activities towards ethylene polymerization, and produced polyethylenes with high molecular weight and highly linear feature as well as unimodal distribution.
基金supported by the National Natural Science Foundation of China (20825517, 20890020)Ministry of Science and Technology of China (2007CB714503)
文摘A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneumatic microvalve control was proposed. The sample and reagent solutions were synchronously loaded and injected in the chip-based sample injection module instead of multi-step sequential injection by a multiposition valve and a reciprocating pump as in conventional SIA system. The sample and reagent injection volumes were reduced to ca. 1.1 nL. The present system has the advantages of simple structure, fast and convenient operation, low sample and reagent consumption, and high degree of integration and automation. The system operation conditions were optimized using fluorescein as model sample. Its feasibility in biological analysis was preliminarily demonstrated in enzyme inhibition assay.
