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951.
The present study investigated the modification of mesoscale inhomogeneous distribu-tion of soil wetness, resulting from mesoscale irrigation over arid or semiarid lands in mid-latitude in the later summer or early autumn, on mesoscale climate under conditions withand without synoptic flow influence, using an interactive model between soil and atmo-sphere. The simulations indicated that after a mesoscale irrgation, a wet soil breeze circu-lation was thermally forced, which was, in many features, similar to that of the sea breezecirculation. The influence of synoptic flows on the structure of thermally--induced wet soilbreeze circulation was also discussed. 相似文献
952.
Based upon the effect of land-sea interaction on the paleomonsoon variation and the time series of climatic proxy-indicators, the historical Asian monsoon variation over the last 130,000 and 18,000 years has been reconstructed with an emphasis on the basic characteristics of summer monsoon circulation. The monsoon-climatic cycles and associated model of environmental development over the central and eastern China are proposed and the mechanism of paleomonsoon variation of China preliminarily discussed. The variation of East Asian monsoon circulation should be regarded as a regional result of both solar-radiation changes and the global glacial-interglacial cycles. The episodic uplifting of the Qinghai-Xizang Plateau since the late Miocene has to a large extent controlled the forming and evolution of the paleomonsoon circulation of China. 相似文献
953.
AMSSubjectClassification34C27Thespatialelementinpopulationbiologyisimportanttounderstandthedynamicsofecologicalsystems.ThetheoreticalworksonthisproblemwerepioneeredbySkellamif]in1951andwerereviewedbyLevin[2]in1974.In12],Levinfirstestablishedthiskindofmode… 相似文献
954.
A metal-support interaction between Pd and various kinds of zeolite and metal oxide supports was studied, which were active in the catalytic combustion and selective reduction of NO. The acid-base properties of supports affected the oxidation state, structure and catalytic activity of Pd. The acid sites of zeolite played the role to anchor the dispersed PdO as evidenced by the dynamic structural change of Pd. It was found that the metal-support interaction is an important factor, affecting the oxidation state, structure and catalytic performance of Pd. 相似文献
955.
W. Zielenkiewicz P. Zielenkiewicz P. V. Lapshov 《Journal of Thermal Analysis and Calorimetry》1995,45(4):775-779
The results of calculation of free Gibbs energy and enthalpy of cavity formation were described using the Scaled Particle
and Sinanoglu's theories.
Zusammenfassung Mittels der zitierten Theorien wurden die Resultate der Berechnung der freien Gibbs'schen Energien und Enthalpien für die Hohlraumbildung beschrieben.相似文献
956.
本文考虑Hopfield型模型的收敛性问题和吸引子的吸引域的刻画。证明了N<+∞与N=+∞时Hopfield模型在几乎处处的意义下收敛于吸引集。当N<+∞时,模型将在有限时间内稳定于某一吸引子上.对于N<+∞与N=+ ∞的情形,分别得到了吸引域的一个集的刻画。 相似文献
957.
本文研究Meleard-Roelly(1992,1993)和Metivier(1987)构造的带交互作用的测度值分枝过程的状态性质.我们证明在自然假设下该过程关于Lebesgue测度是绝对连续的,其密度有连续修正且满足一个随机偏微分方程. 相似文献
958.
CHEN BAO-ZHEN 《理论物理通讯》2002,38(7)
The dynamics of a relativistic electron submitted to an intense, plane wave, linearly polarized laser field is reviewed. Based on the dynamics, the temperature of the electron in the laser field is delined and calculated. It is found that the calculated temperature fits the first temperature observed in the experiment by Malka et al. A model to evaluate the electron temperature by taking the electron-ion scattering into account is proposed. It is found that when I ≥ 4.0 × 101s W/cm2 the electron temperature by considering the scattering, T hs, is evidently larger than the electron temperature without considering the scattering, Th. This result is in favor of explaining the two-temperature distribution of the electron energy observed in the experiment by Malka et al. 相似文献
959.
The compressible Navier-Stokes equations discretized with a fourth order accurate compact finite difference scheme with group velocity control are used to simulate the Richtmyer-Meshkov (R-M) instability problem produced by cylindrical shock-cylindrical material interface with shock Mach number Ms=1.2 and density ratio 1:20 (interior density/outer density). Effect of shock refraction, reflection, interaction of the reflected shock 相似文献
960.
为精确计算出陀螺仪内部温度场,有效改善影响陀螺仪精度的温度梯度分布状况,采用了精度更高的流固耦合计算方法,结合FLUENT软件,对卫星等上使用的某型长寿命陀螺仪浮子组件进行了内部流场及温度场计算。结果表明,浮子内部结构形式对高速旋转的电机产生的介质流场有较大影响,合理的结构设计有利于降低电机功耗;陀螺仪浮子表面存在最大温差为0.52℃的温度梯度,其所产生的液流力矩会对陀螺仪精度产生一定影响;浮子表面温度分布表现出一定的对称性和规律性。计算结果为下一步旨在减小温度梯度、提高陀螺仪精度的精密分区温控提供了数据基础。 相似文献