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Effect of Uncertainty of the Pre-Exponential Factor on Kinetic Parameters of Hydrocarbon Generation from Organic Matter and its Geological Applications

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 211-218页

作者： WANG min lu Shuangfang XUE Haitao YU Zhanqing Research Institute of Unconventional Petroleum and Renewable Energy China University of Petroleum

The source rock sample of the Shahejie Formation （upper Es4） in Jiyang Sag was pyrolyzed under open system with the Rock-Eval-lI apparatus, and then kinetic model parameters were calibrated for investigating the effect of uncertainty of pre-exponential factors on kinetic parameters and geological applications, where the parallel first-order reaction rate model with an average pre- exponential factor and discrete distribution activity energies was used. The results indicate that when the pre-exponential factor changes from low to high, an extreme value for residual errors occurs. And with the increasing pre-exponential factor, the distribution shape of activation energies are nearly the same, but the values of activation energies move higher integrally, and the average activation energy increases about 12 kJ/mol for every 10-fold of the pre-exponential factors. Extrapolating the geological heating rate of 3.3 ~C/Ma, the results show that with the increases in pre-exponential factor, the geological temperature corresponding to TRo.5 （transforming ratio of hydrocarbon generation is 50%） increases gradually, and the additional temperature gradually decreases. Combined with geochemical data of source rock, the kinetic parameters with different pre-exponentia[ factors are used to calculate the transformation ratio of hydrocarbon generation, and the result indicates that kinetic parameters corresponding to the better optimized pre-exponential factor are more suitable. It is suggested that the risk assessment of hydrocarbon generation kinetic parameters should be enhanced when using the kinetic method to appraise the oil-gas resources. Meantime, the application result of different kinetic parameters should be verified with geological and geochemical data of source rock in the target area; therefore, the most suitable kinetic parameters for target can be obtained.

关键词： Pre-exponential factor activation energy uncertainty hydrocarbon generation kinetics,geological application

Performance and Analysis of a Model for Describing Layered Leaf Area Index of Rice

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Agricultural Sciences in China 2011年第3期10卷 351-362页

作者： lu Chuan-gen YAO Ke-min HU Ning Institute of Food Crops Jiangsu Academy of Agricultural Sciences Nanjing 210014 P.R. China College of Applied Meteorology Nanjing University of Information Science and Technology Nanjing 210044 P.R. China

Layered leaf area index （LAIk） is one of the major determinants for rice canopy. The objective of this study is to attain rice LAI k using morphological traits especially leaf traits that affected plant type. A theoretical model based on rice geometrical structure was established to describe LAI k of rice with leaf length （Li）, width （Wi）, angle （Ai）, and space （Si）, and plant pole height （H） at booting and heading stages. In correlation with traditional manual measurement, the model was performed by high R2-values （0.95-0.89, n=24） for four rice hybrids （Liangyoupeijiu, Liangyou E32, Liangyou Y06, and Shanyou 63） with various plant types and four densities （3 750, 2 812, 1 875, and 1 125 plants per 100 m2） of a particular hybrid （Liangyoupeijiu）. The analysis of leaf length, width, angle, and space on LAI k for two hybrids （Liangyoupeijiu and Shanyou 63） showed that leaves length and space exhibited greater effects on the change of rice LAI k . The radiation intensity showed a significantly negative exponential relation to the accumulation of LAI k , which agreed to the coefficient of light extinction （K）. Our results suggest that plant type regulates radiation distribution through changing LAI k . The present model would be helpful to acquire leaf distribution and judge canopy structure of rice field by computer system after a simple and less-invasive measurement of leaf length, width, angle （by photo）, and space at field with non-dilapidation of plants.

关键词： canopy structure layered leaf area index (LAI k ) model plant type rice

Quasihole Tunneling in Disordered Fractional Quantum Hall Systems

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Chinese Physics Letters 2019年第8期36卷 84-87页

作者： min lu Na Jiang Xin Wan Zhejiang Institute of Modern Physics Zhejiang UniversityHangzhou 310027 CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190

Fractional quantum Hall systems are often described by model wave functions,which are the ground states of pure systems with short-range interaction.A primary example is the Laughlin wave function,which supports Abelian quasiparticles with fractionalized *** the presence of disorder,the wave function of the ground state is expected to deviate from the Laughlin *** study the disorder-driven *** of the quantum Hall state by analyzing the evolution of the ground state and the single-quasihole *** particular,we demonstrate that the quasihole tunneling amplitude can signal the fractional quantum Hall phase to insulator transition.

关键词： Quasihole Systems Quantum

Energetic Argument for Bimodal Black Hole Accretion discs

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Chinese Physics Letters 2002年第10期19卷 1562-1564页

作者： Lin Yi-Qing lu Ju-Fu Gu Wei-min Department of Physics Xiamen University Xiamen 361005 Service d'Astrophysique CEA/DSM/DAPNIA CE-Saclay 91191 Gif-sur-Yvette France

Based on simple energetic considerations, we show that two crucial ingredients of bimodal black hole accretion discs, namely the sonic point and the transition radius, can be determined from the disc constant paramete... 详细信息

关键词： Gravitation

PRESSURE FluCTUATIONS BENEATH SPATIAL HYDRAULIC JUMPS

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Journal of Hydrodynamics 2006年第6期18卷 723-726页

作者： YAN Zhong-min ZHOU Chun-tian lu Shi-qiang College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China Shanghai Academy of Environmental Sciences Shanghai 200233 China

This article deals with statistical analysis of pressure fluctuations at the bottom of spatial hydraulic jumps with abrupt lateral expansions. The effects of the channel expansion ratio and inflow condition on the power spectral and dominant frequency were examined. Pressure data were recorded for different Froude numbers ranging from 3.52 to 6.86 and channel expansion ratios ranging from 1.5 to 3.0. A sampling frequency of 100 Hz was selected. The measurements were conducted in the bed of a glass-walled laboratory flume by means of pressure transducers and data acquisition systems. Power spectra as well as dominant frequency and some other statistical characteristics of fluctuating pressure beneath hydraulic jumps were obtained. Test results were compared with those of classical jump, which indicates that the peak frequencies and intensity coefficients of pressure fluctuations are higher than those of the corresponding classical jumps.

关键词： spatial hydraulic jumps pressure fluctuation,stochastic analysis frequency amplitude

Effects of Cerium Doping at Ti Sites and Europium Doping at Ba Sites on Dielectric Properties of BaTiO_3 Ceramics

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Chemical Research in Chinese Universities 2006年第4期22卷 515-519页

作者： ZHANG Ya-min SUN Xiu-yun lu Da-yong College of Chemistry Jilin University Changchun 130021 P. R. China Applied Chemistry Jilin Institute of Chemical Technology Jilin 132022 P. R. China Venture Business Laboratory Department of Chemistry and Chemical Engineering Faculty of Engineering Yamagata University Yonezawa 992-8510 Japan

Two special rare earth elements cerium and europium were chosen to conduct chemical modification of the BaTiO3 structure. The cold-pressing ceramic processing technique was used to prepare barium titanate ceramics doped with Ce at Ti sites and with Eu at Ba sites on the base of formulas Ba （ Ti1 -x Cex ） O3 （x = 0. 05, 0. 10 ）（CBT） and （ Ba1-y Euy ） Ti1-x/8O3 （ y = 0. 05, 0. 10）（EBT）. Associated with structures and microstructures, the effects of cerium and europium doping on dielectric properties of BaTiO3 ceramics were discussed. The CBT ceramics exhibit a pseudocubic perovskite structure, while the EBT ceramics exhibit a tetragonal perovskite structure with the exception of the existence of a small percentage of the Eu2Ti2O7 phase. The Curie peak of BaTiO3 shifts towards room temperature at rates of 3 ℃/mol Ce atoms and 10 ℃/mol Eu atoms（ Eu≤5% ）, respectively. Compared with the CBT ceramics, the EBT ceramics show significant advantages, such as a narrow fine grain size distribution（ 1 μm）, a lower porosity and a higher density（5.85 g/cm^3）, more stable dielectric-temperature dependence（ ε′= 1600-1800 at t 〈 50℃ ） and a lower dissipation factor（〈 0. 05 ）. The stability of dielectric constant with frequency in BaTiO3 can extend to 107 Hz due to Ce and Eu doping.

关键词： Cerium Europium Barium titanate Cold-pressing technique Dielectric constant

Nitrogen-skinned carbon nanocone enables non-dynamic electrochemistry of individual metal particles

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Science China Chemistry 2022年第10期65卷 2031-2037页

作者： Chen Liu Jianan Xu Han Gao min Zhou Lehui lu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130000China University of Science and Technology of China Hefei 230026China

Nano-impact electrochemistry is an efficient way to probe the physical and chemical properties of individual ***,limited by the weak adsorption between particles and a microelectrode(ME),the particle collision events evolve randomly to be elastic or *** events occur intermittently to produce unmarked transient signal sets that seriously interfere with single particle ***,we report a nitrogen-skinned carbon nanocone electrode(NS-CNCE) to enhance its adsorption capacity greatly towards metal particles and thus realize non-dynamic(i.e.,inelastic impacts) single particle *** surface of NS-CNCEs characteristic of excellent adhesion,smoothness,and conductivity can effectively capture the landing metal particles to form a stable contact for efficient electronic *** superior NS-CNCEs,we investigated electrochemical oxidation of Ag(or Au) particles and electrocatalytic amplification of Pt particles,respectively,under non-dynamic *** determined particle size is highly consistent with the physical *** analysis of transient signals confirms the strong adhesion of NS-CNCEs to metal particles,which is also in line with the prediction of a particle-electrode adsorption energy *** proposed strategy has effectively solved the major challenge of general single metal particle collision analysis.

关键词： non-dynamic electrochemistry inelastic impacts single particle collisions nitrogen-skinned carbon

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Grain refining of Er added to Ti-22Al-25Nb alloy and morphology of erbium precipitates

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Rare Metals 2013年第1期32卷 5-11页

作者： Jing-Ru Dai Hui-min lu Zhi-Jin Cai Chao An School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics

In order to investigate the effect of erbium （Er） on the microstructure of orthorhombic Ti2A1Nb-based alloys, four testing alloys were prepared by adding differ- ent contents of the rare earth metal Er to Ti-22A1-25Nb alloy and optical microscopy, X-ray diffraction, scanning electron microscopy, electron probe microanalysis, energy- dispersive spectrometry, and transmission electron microscopy were used. The results show that the addition of Er is capable of grain refining and the refinement effect is more obvious with increasing content of Er. The Er203 dispersoids formed by internal oxidation and A13Er com- pound particles are observed in Er-doped alloys and the number of Er precipitates is increased with increasing Er addition. It is likely that the solubility of Er in the Ti2A1Nb alloy is very low and Er precipitates tend to segregate at grain boundaries, which together with the surface activity of rare earth elements is supposed to decrease the prior B2 grain size of Ti-22A1-25Nb alloy effectively.

关键词： Ti2A1Nb-based alloys Rare earth erbium(Er) Microstructure Erbium precipitates

Fhotocatalytic degradation of polybrominated diphenyl ethers in pure water system

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Frontiers of Environmental Science & Engineering 2016年第2期10卷 229-235页

作者： min ZHANG Jian lu Yiliang HE P. Chris WILSON School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Indian River Research and Education Center University of Florida Fort Pierce FL 34945 USA

Due to the low water solubility of polybromi- nated diphenyl ethers, organic solvent is usually added into the oxidation system to enhance the removal efficiency. In this study the photocatalytic degradation of decabromodi- phenyl ether （BDE209）, a type ofpolybrominated diphenyl ether used throughout the world, in pure water without the addition of organic solvent was investigated. In the pure water system, BDE209 was not dissolved but dispersed as nano-scale particles with a mean diameter of 166 nm. Most of BDE209 （〉 98%） were removed within 4 h and the final debromination ratio was greater than 80%. Although the addition of organic solvent （tetrahydrofuran, THF） could lead to a relatively high BDE209 degradation rate, the final debromination ratio （〈 50%） was much lower than that in pure water system. Major oxidation inter- mediates of tetrahydrofuran, including tetrahydro-2-fura- nol and y-butyrolactone, were detected indicating the engagement of THF in the BDE209 degradation process. The photocatalytic degradation of BDE209 in the pure water system followed first-order kinetics. The BDE209 degradation rate constant increased from 0.0011 to 0.0023 min-1 as the pH increased from 3 to 9.

关键词： polybrominated diphenyl ethers photocataly-tic degradation solvent