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Journal of Thermal Science 1993年第3期2卷 196-204页

作者： Wen-Qiang Lu Department of Physics, Dvision of Thermal Science, graduate School, Chinese Academy of Sciences, P.O. Box 3.08, beijing 10003.,{2. 1. Department of Physics Dvision of Thermal Science Graduate School Chinese Academy of Sciences P.O. Box 3908 100039 Beijing China

A boundary element method has been developed for analysing heat transport phenomena in solitary wave on falling thin liquid films at high Reynolds numbers. The divergence theorem is applied to the non-linear convective volume integral of the boundary element formulation with the pressure penalty function. Consequently, velocity and temperature gradients are eliminated, and the complete formulation is written in terms of velocity and temperature. This provides considerable reduction in storage and computational requirements while improving accuracy. The non-linear equation systems of boundary element discretization are solved by the quasi-Newton iterative scheme with Broyden's update. The streamline maps and the temperature distributions in solitary wave and wavy film flow have been obtained, and the variations of Nusselt numbers along the wall-liquid interface are also given. There are large cross-flow velocities and S-shape temperature distributions in the recirculating region of solitary wave. This special flow and thermal process can be a mechanism to enhance heat transport.

关键词： solitary wave thin falling liquid films mechanism to enhance heat transport boundary element computation of convective terms

Combustion characteristics of aluminium-iron oxide in SHS-gravitational process

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Journal of university of Science and Technology beijing 2002年第3期9卷 221-223页

作者： Tao Lin, Shiju Guo, Sheng Yin, and Zhimeng GuoMaterials Science and Engineering School, university of Science and Technology beijing, beijing 100083.{3. (Received 2.01-10-15) beijing Univ Sci & Technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

In order to get high quality of products, the combustion of aluminium-ironoxide thermite in SHS-gravitational process must be under control. The effects of thermite fillingdensity, hole in thermite and inclined angle of pipe on combustion rate were studied. It shows thatthe combustion rate decreases with the decrease of filling density. The thermite combusts downwardsthe pipe much more quickly if there are holes in the thermite. And the combustion rate increaseswith the increase of the inclined angle of pipe. The experiment results show that the combustion ofthermite is predominantly controlled by gas phase reaction, which is attributed to the hightemperature of the thermite combustion.

关键词： thermite reaction SHS chemical synthesis composites

Design of a new dynamical core for global atmospheric models based on some efficient numerical methods

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Science china Mathematics 2004年第z1期47卷 4-21页

作者： WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china Department of Computational Mathematics, Academy of Mathematics and System Sciences, Peking {2., beijing 100871, china Chinese Acad Sci Inst Atmospher Phys State Key Lab Numer Modeling Atmospher Sci & Geop Beijing 100029 Peoples R China Peking Univ Acad Math & Syst Sci Dept Computat Math Beijing 100871 Peoples R China

A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community Atmospheric Model Version 2.(CAM2. of NationalCenter for Atmospheric Research (NCAR), are included.

关键词： dynamical core, equal-area mesh, anti-symmetry, effective energy conservation.

Gas-water stratified flow patterns from electromagnetic tomography

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Petroleum Science 2009年第3期6卷 254-258页

作者： Wang Xiaoxing Wu Xiling School of Resources and Information Technology China University of Petroleum Beijing 102249 China

Because of gravitational differentiation of multi-phase fluids, gas-water flow is usually stratified in highly inclined or horizontal gas wells. By using electrode arrays to scan flowing fluids, electromagnetic tomography can identify the flow patterns of mixed fluid from the different electrical properties of gas and water. The responses for different gas-water interface locations were calculated and then physical measurements were undertaken. We compared the results of the numerical simulation with the experimental data, and found that the response characteristics were consistent in the circumstances of uniform physical fields and stratified flows. By analyzing the signal characteristics, it is found that, with the change of the interface location, the response curves showed ＂steps＂ whose position and width were decided by the location of fluid interface. The measurement accuracy of this method depended on the vertical distance between adjacent electrodes. The results showed that computer simulation can simulate the measurement of the electromagnetic tomography accurately, so the physical experiment can be replaced.

关键词： Electromagnetic tomography stratified flow gas-water numerical simulation physical experiment

KINETIC FEATURES OF HYDROCARBON GENERATION OF DESMOCOLLINITE FROM LATE PERMIAN COALS IN SOUTH china

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Scientia Geologica Sinica 2000年第1期 97-102页

作者： Sun Xuguang and Wang Guanyu (Department of Geology Peking university, beijing 10087) Hao Duohu and Jin Kuili( beijing {3. School, china university of Mining and Technology beijing 100083.

The kinetic parameters of hydrocarbon generation from coals or kerogens, can indicate the structure of their internal molecular. The structure has been extensively studied by laboratory experiments. In this paper, Rock-Eval II were carried out on desmocollinite, which is isolated from Late Permian coals in Shuicheng, Guizhou Province in southern china. The determination of the kinetic parameters shows that the activation energies are correlated with chemical structures. The desmocollinite show a broader distribution of activation energies, thus reflecting a more complex composition. The average activation energy of barkinite, desmocollinite and fusinite are 177 kJ/mol, 2.0 kJ/mol and 3.0 kJ/mol. Respectively. We can conclude that the order for the three macerals to form oil is barkinite -vitrinite -fusinite.

关键词： rock KINETIC FEATURES OF HYDROCARBON GENERATION OF DESMOCOLLINITE FROM LATE PERMIAN COALS IN SOUTH china

HARMONIC MAPS VERSUS POISSON EQUATIONS ON NONCOMPACT RIEMANNIAN MANIFOLDS

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Systems Science and Mathematical Sciences 2000年第3期13卷 333-336页

作者： MA Li(Department of Mathematical Sciences, Tsinghua university, beijing 100084,{2.) 清华大学数学系北京 100084

Suppose there is a map from a noncompact riemannian manifold into a nonpositively curved riemannian manifold such that its tension field is in a suitable Banach space. Then there exists an intimate relationship between harmonic maps and Poisson equations on the domain manifold. On the basis of this observation, we can extend some results of the previous work of Tam and Li.

关键词： Harmonic maps Poisson equations complete manifolds

Electrophysiological research of synapse formation from beginning to maturity

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Chinese Science Bulletin 1998年第1期43卷 55-59页

作者： XIE Zuoping and ZHENG Yufang State Key Laboratory of Biomembrane and Membrane Biotechnique Department of Biological Sciences and Biotechnology, Tsinghua university, beijing 100084,{2. State Key Laboratory of Biomembrane and Membrane Biotechnique Tsinghua University Beijing China Department of Biological Sciences and Biotechnology Tsinghua University Beijing China

The development of synapses is an important question in neurobiology. We employ patchclamp technique to record MEPCs and EPCs of myoballs in Xenopus cell culture. The rate of EPC/MEPC is related with synapses maturation. Accordingly, we define the mature synapses as those whose rate of presynaptic membrane’s EPC to MEPC is more than 8. The process of maturation needs about 2.5 h after neurites contact with myoballs. We divide the development of synapses into three stages: young, developing and mature. The neurotransmitters stack gradually and increase by hundreds of times along with young synapses growing into maturity. So the process of synapses maturation should include presynaptic membrane specialization, postsynaptic membrane specialization and neurotransmitters stack.

关键词： definition of mature synapse α latrotoxin (α LTX) neurotransmitter stack.

3. Integrated Geological Modeling in Tongshan Copper Deposit,Heilongjiang Province,china

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地学前缘 2009年第S1期16卷 282-283页

作者： Gongwen Wang,Limei Wang,Ge Cui,Chengyin Tan,Shanyan Jin School of Earth Sciences and Resources,china university of Geosciences({2.),{2. 100083.china.

In this paper,3.-GIS reconstruction and interpolation approach,additional virtual borehole technology and BP network technology are used to explore the concealed ore *** virtual borehole has same function as reality b... 详细信息

关键词： 3. geological modeling virtual borehole BP network mineral exploration Tongshan copper deposit

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塔里木盆地库车坳陷储层裂缝分布规律

天然气工业 2004年第9期24卷 23-25,i023页

作者：曾联波周天伟石油大学石油天然气成藏机理教育部重点实验室石油大学资源与信息学院

根据岩心、测井和露头区资料 ,对塔里木盆地库车坳陷储层裂缝的分布特征进行了综合分析 ,并利用数值模拟方法 ,对白垩系储层裂缝的发育规律进行了预测。该区主要发育有北西向、北东向和近南北向中高角度构造裂缝。纵向上 ,以三叠系、下... 详细信息

根据岩心、测井和露头区资料 ,对塔里木盆地库车坳陷储层裂缝的分布特征进行了综合分析 ,并利用数值模拟方法 ,对白垩系储层裂缝的发育规律进行了预测。该区主要发育有北西向、北东向和近南北向中高角度构造裂缝。纵向上 ,以三叠系、下侏罗统阿合组、下白垩统巴什基其克组和古近系库姆格列木群裂缝发育 ,裂缝的发育程度受岩性和层厚控制。在平面上 ,下白垩统裂缝发育区主要分布在克拉苏—依奇克里克构造带 ,古近系裂缝发育区主要分布在克拉苏—大北一带 ,在依南构造带 ,三叠系、中下侏罗统和新近系吉迪克组裂缝也比较发育。

关键词：下侏罗统构造带下白垩统塔里木盆地库车坳陷储层裂缝古近系裂缝发育三叠系岩心

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采用预测控制进行纵向塞曼幅值热稳频的研究

中国激光 1998年第5期25卷 421-426页

作者：戴高良殷纯永谢广平清华大学精密仪器与机械学系北京100084 中国矿业大学北京研究生部北京100083

产生纵向塞曼频率分裂的He—Ne激光器输出左、右旋圆偏振光,其光强差和激光频率呈稳定的调谐曲线。装置利用单片机采集幅值信号,采用预测控制理论进行数字调节,输出PWM(PulseWidth Modulation)信号补偿激光管的温度以实现热稳频控制。... 详细信息

产生纵向塞曼频率分裂的He—Ne激光器输出左、右旋圆偏振光,其光强差和激光频率呈稳定的调谐曲线。装置利用单片机采集幅值信号,采用预测控制理论进行数字调节,输出PWM(PulseWidth Modulation)信号补偿激光管的温度以实现热稳频控制。为实现对热稳频大滞后、非线性这一复杂系统的高质量控制,提出了预测控制方法,该方法克服了传统PID(Proportional IntegralDifferential)调节中存在的调整工作量大,控制后果不能及时反馈的不足,适用于各种热稳频过程。数字仿真和实验验证预测控制是稳定的,对模型误差的适应能力强。对10s采样周期,估算得系统频率稳定度达6.7×10^(-9)。

关键词：塞曼激光模型预测控制热稳频 PID调节器