Electromagnetic emission(EME) is a kind of physical phenomenon accompanying the process of deformation and fracture of loaded coal and rock and it is of importance in quantitatively analyzing its characteristics.This ...Electromagnetic emission(EME) is a kind of physical phenomenon accompanying the process of deformation and fracture of loaded coal and rock and it is of importance in quantitatively analyzing its characteristics.This will reveal the process of deformation and fracture of coal and predicting dynamic disasters in coal mines.In this study,the G-P(Grassberger and Procaccia) algorithm,calculation steps of the(if only 1 dimension) correlation dimension of time series and the identification standards of chaotic signals are introduced.Furthermore,the correlation dimensions of EME and the acoustic emission(AE) signals of time series during deformation and fracture of coal bodies are calculated and analyzed.The results show that the time series of pulses number of EME and the time series of AE count rate are chaotic and that the saturation embedding dimensions of a K3 coal sample are,respectively,5 and 6.The results can be used to provide basic parameters for predicting of EME and AE time series.展开更多
The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deprot...The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deproteinization with Sevag method and ethanol precipitation. The pure schizophyllan was obtained by gel filtration chromatography with Sephacryl S-500,and its molecular characteristics were examined. The result showed that the molecular weight was 3.8×104 ,and the schizophyllan consisted of glucose with β-(1→6)-glucosidic linkages.展开更多
In this paper,the shear wave splitting features of the Longtan reservoir area are studied by adopting the traditional cross-correlation coefficient method and polarization analysis,using the data recorded by the seism...In this paper,the shear wave splitting features of the Longtan reservoir area are studied by adopting the traditional cross-correlation coefficient method and polarization analysis,using the data recorded by the seismic network founded by a project under the National Science and Technology Pillar Program from April 2009 to April 2010.We found that most of polarization directions at seismic stations are consistent with the direction of the overall regional stress field,but local structures and faults may control or influence the fast shear-wave polarization direction.The time-delay normalized to source-station path is between 10 to 25ms/km,and among them,the time-delay is about 10ms/km at the LIL and XIL sites,which are farther away from the dam.The water depth is relatively shallow and seismic activity relatively weak after water storage,indicating the effect of reservoir water penetration,or loading,on the state of cracks in the reservoir area.We also found that the delay time changes consistently with the water level at stations DPD and GAL.It may be related to crack expansion and water penetration caused by the reservoir impoundment.展开更多
Spray structure and atomization characteristics were investigated through a comparison of a porous and a shear coaxial injector. The porous injector shows better atomization performance than the shear coaxial injector...Spray structure and atomization characteristics were investigated through a comparison of a porous and a shear coaxial injector. The porous injector shows better atomization performance than the shear coaxial injector. To in- crease atomization performance and mixing efficiency of two-phase jets, a coaxial porous injector which can be applicable to liquid rocket combustors was designed and tested. The characteristics of atomization and spray from a porous and a shear coaxial injector were characterized by the momentum flux ratio. The breakup mechanism of the porous injector is governed by Taylor-Culick flow and axial shear forces. Momentum of injected gas flow through a porous material which is composed of sintered metal is radically transferred to the center of the liquid column, and then liquid column is effectively broken up. Although the shapes of spray from porous and shear co- axial jets were similar for various momentum ratio, spray structures such as spray angle and droplet sizes were different. As increasing the momentum flux ratio, SMD from the porous injector showed smaller value than the shear coaxial injector展开更多
On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(...On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(saturated, aromatic, resin, and asphalene fractions). However, little is known about the effect of volatile components in oil on diamondoid generation and diamondoid indices due to the lack of attention to these components in experiments. In this study, the effect of volatile components in oil on diamondoid generation and maturity indices was investigated by the pyrolysis simulation experiments on a normal crude oil from the HD23 well of the Tarim Basin and its residual oil after artificial volatilization, combined with quantitative analysis of diamondoids. The results indicate that the volatile components(≤n C12) in oil have an obvious contribution to the generation of adamantanes, which occurs mainly in the early stage of oil cracking(Easy Ro<1.0%), and influences the variations in maturity indices of adamantanes; but they have no obvious effect on the generation and maturity indices of diamantanes. Therefore, some secondary alterations e.g., migration, gas washing, and biodegradation, which may result in the loss of light hydrocarbons in oil under actual geological conditions, could affect the identification of adamantanes generated during the late-stage cracking of crude oil, and further influence the practical application of adamantane indices.展开更多
基金Projects 50427401 supported by the National Natural Science Foundation of China2006BAK03B06 by the National Eleventh Five-Year Key Science & Technology Project of China+2 种基金the New Century Excellent Talent Program from the Ministry of Education (No.NCET-07-0799)the Fok Ying-Tong Education Foundation for Young Teachers in Higher Education Institutions of China (No.111053)the Beijing Science and Technology New Star Plan (No.2006A081)
文摘Electromagnetic emission(EME) is a kind of physical phenomenon accompanying the process of deformation and fracture of loaded coal and rock and it is of importance in quantitatively analyzing its characteristics.This will reveal the process of deformation and fracture of coal and predicting dynamic disasters in coal mines.In this study,the G-P(Grassberger and Procaccia) algorithm,calculation steps of the(if only 1 dimension) correlation dimension of time series and the identification standards of chaotic signals are introduced.Furthermore,the correlation dimensions of EME and the acoustic emission(AE) signals of time series during deformation and fracture of coal bodies are calculated and analyzed.The results show that the time series of pulses number of EME and the time series of AE count rate are chaotic and that the saturation embedding dimensions of a K3 coal sample are,respectively,5 and 6.The results can be used to provide basic parameters for predicting of EME and AE time series.
基金National Nature Science Foundation of China (No.31171662)"973"National Key Basic Research and Development Program(No.2012CB518202)+1 种基金Project of Qinghai Development of Science and Technology(No.2011-N-150)Key Project of GLD of PLA
文摘The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deproteinization with Sevag method and ethanol precipitation. The pure schizophyllan was obtained by gel filtration chromatography with Sephacryl S-500,and its molecular characteristics were examined. The result showed that the molecular weight was 3.8×104 ,and the schizophyllan consisted of glucose with β-(1→6)-glucosidic linkages.
基金sponsored by the National Key Technology R&D Program(2008BAC38B02),China
文摘In this paper,the shear wave splitting features of the Longtan reservoir area are studied by adopting the traditional cross-correlation coefficient method and polarization analysis,using the data recorded by the seismic network founded by a project under the National Science and Technology Pillar Program from April 2009 to April 2010.We found that most of polarization directions at seismic stations are consistent with the direction of the overall regional stress field,but local structures and faults may control or influence the fast shear-wave polarization direction.The time-delay normalized to source-station path is between 10 to 25ms/km,and among them,the time-delay is about 10ms/km at the LIL and XIL sites,which are farther away from the dam.The water depth is relatively shallow and seismic activity relatively weak after water storage,indicating the effect of reservoir water penetration,or loading,on the state of cracks in the reservoir area.We also found that the delay time changes consistently with the water level at stations DPD and GAL.It may be related to crack expansion and water penetration caused by the reservoir impoundment.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean Government(MEST)(NRF-2011-0015435 and NRF-2012M 1A3A3A02033146)
文摘Spray structure and atomization characteristics were investigated through a comparison of a porous and a shear coaxial injector. The porous injector shows better atomization performance than the shear coaxial injector. To in- crease atomization performance and mixing efficiency of two-phase jets, a coaxial porous injector which can be applicable to liquid rocket combustors was designed and tested. The characteristics of atomization and spray from a porous and a shear coaxial injector were characterized by the momentum flux ratio. The breakup mechanism of the porous injector is governed by Taylor-Culick flow and axial shear forces. Momentum of injected gas flow through a porous material which is composed of sintered metal is radically transferred to the center of the liquid column, and then liquid column is effectively broken up. Although the shapes of spray from porous and shear co- axial jets were similar for various momentum ratio, spray structures such as spray angle and droplet sizes were different. As increasing the momentum flux ratio, SMD from the porous injector showed smaller value than the shear coaxial injector
基金financially supported by the National Natural Science Foundation of China(Grant Nos.41172115&41372138)the National Science&Technology Major Project of the Ministry of Science and Technology of China(Grant No.2011ZX05008-002-32)China Postdoctoral Science Foundation(Grant No.2014M561002)
文摘On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(saturated, aromatic, resin, and asphalene fractions). However, little is known about the effect of volatile components in oil on diamondoid generation and diamondoid indices due to the lack of attention to these components in experiments. In this study, the effect of volatile components in oil on diamondoid generation and maturity indices was investigated by the pyrolysis simulation experiments on a normal crude oil from the HD23 well of the Tarim Basin and its residual oil after artificial volatilization, combined with quantitative analysis of diamondoids. The results indicate that the volatile components(≤n C12) in oil have an obvious contribution to the generation of adamantanes, which occurs mainly in the early stage of oil cracking(Easy Ro<1.0%), and influences the variations in maturity indices of adamantanes; but they have no obvious effect on the generation and maturity indices of diamantanes. Therefore, some secondary alterations e.g., migration, gas washing, and biodegradation, which may result in the loss of light hydrocarbons in oil under actual geological conditions, could affect the identification of adamantanes generated during the late-stage cracking of crude oil, and further influence the practical application of adamantane indices.