NUMERICAL SIMULATION OF ACIDIFICATION PROCESSES IN COLD CUMULUS CLOUDS

In this paper, a 1-D time dependent cold cumulus chemistry model is presented. In the coldcumulus model, 4 categories of hydrometeors: cloud drops, raindrops, cloud ice crystals, graupelparticles, and 18 microphysical interactions are considered, In the chemical model, the source andsink terms for pollutants include: the complicated interactions between pollutants (gases andaerosol particles) and the hydrometeors (especially ice crystals and graupel particles), the ex-changes of chemical compounds between two hydrometeors accompanying microphysical processesand the aqueous oxidations of S (IV) to S (VI). The two models are combined to study the acidifi-cation processes in cold cumulus clouds.     

SYNERGISTIC EFFECTS ON ATMOSPHERIC ANOMALY OF THE TROPICAL INDIAN AND PACIFIC OCEANS IN NORTHERN WINTER

In terms of observational analysis and numerical simulations,study is performed of thesynergistic effects of the tropical Indian Ocean and Pacific SSTA on the atmosphere in northern win-ter.It turns out that the SSTA features show in-phase variation for the Indian Ocean and the central/eastern Pacific at low latitudes and anti-phase change compared with that in the neighborhood of thewestern Pacific“warming pool”.When negative SSTA in the western Pacific and positive SSTA inthe central/eastern Pacific and the Indian Ocean are available,the 500 hPa height anomaly exhibits awave train of a positive-negative-positive anomaly following a great-circle path emanating from thesubtropical western Pacific via the NW portion to North America,with enhanced westerly jet overmidlatitude East Asia and the NW Pacific,and v.v.The comparison to the results from the numeri-cal modeling of the tropical western Pacific SSTA reveals the importance of the synergistic effects ofthe oceans on atmospheric circulations.     

地震灾场的模拟与模拟控制问题研究（Ⅰ）地震灾场模拟

本文将离散事件系统仿真的方法引入到地震工程研究之中．在论述地震灾场模拟与离散事件系统仿真的共性与差异的基础上，以城市地震次生火灾的发生与扑救过程为背景，发展了场、时域复合仿真模型，提出了城市地震灾场的综合模拟算法．实例研究表明，本文建议的地震灾场模拟算法可以揭示复合型工程系统地震反应的一系列特征参数。     

An effective approach to determine the dynamic source parameters

In this study, we present a new and effective method to determine the dynamic source parameters (i.e., stress drop and strength distribution). We first assume that the kinematic source parameters, i.e., the slip and rupture time distributions on the fault plane, are known from the previous source inversion studies. Then, using the seismic source representation theorem we determine the dynamic stress field on a fault plane from known kinematic parameters. Finally, we determine the strength of the fault defined as the peak stress just before the rupture. We have tested the validity of this method by using an illustrative two-dimensional analytical example. To assess the applicability of this method, we have applied it to study the 1979 Imperial Valley earthquake, and obtained consistent results with those ofMiyatake's (1992) andQuin's (1990). Compared with previous methods, this new method is simple, straightforward and accurate, and needs much less calculation. Therefore, it is expected to be useful in exploring the seismic source process.     

白杨河水库砼坝的地震动力分析

水坝抗震能力的评估在新疆具有重要的现实意义．采用有限单元法对白杨河砼坝的动力强度及稳定性进行了计算，结果表明地震时坝的破坏不取决于空库或是满库，而是与它们的周期有关；而且下游坝面遭到破坏的可能性大于上游坝面．在考虑水平及竖向地震荷载作用下，白杨河砼坝满足强度及稳定性要求。     

图象恢复在工业CT中的应用

对于以影象增强器为检测系统的目标旋转式工业ＣＴ，分析了其图象退化的因素，采用对一维投影数据进行图象恢复的方法来提高ＣＴ图象质量。文中给出图象恢复公式，从计算机模拟和实验图象恢复的结果可看到所用方法提高了图象清晰度。     

大同盆地内砂板梁上断裂新活动及其力学实验模拟

通过野外实地考察、野外现场力学实验及室内力学实验模拟断裂的新活动，来研究砂板梁新隆起的活动构造特征和类型。旨在从实验模拟与野外实践相结合的基础上，对活动构造，特别是对断裂新活动在第四纪松散沉积层中特殊的表现形式进行研究，寻找第四纪松散沉积层中断裂新活动的有效识别标志，这是准确判定断裂新活动的关键，对工程地质评价及区域性地震危险性分析有很好的实用价值     

地震构造活动的模拟试验

本在活动构造考察及研究的基础上，采用先进的精密仪器仪表，在模拟试验中自控制监测构造活动情况，深入研究地震前后的断裂运行特征及其与地震的关系，这对圈定地震危险区和判定可能发生强震的破裂段，为国民经济建设提供可靠的依据，对逐步实现地震预报，最大限度地减轻地震灾害，均具有重要实际的意义     

NUMERICAL SIMULATIONS OF HEATING ANOMALY EFFECTS OF TIBETAN PLATEAU ON CIRCULATION IN SUMMER

A 5-layer numerical model with p-σ incorporated coordinate system and primitive equations is used to simulatethe effects of heating anomaly at and over the Tibetan(Qinghai-Xizang)Plateau on the circulations in East Asia in sum-mer,The model is described briefly in the text and the results are analysed in somewhat detail.Results show that the sur-face albedo,the drag coefficient,the evaporation rate and the ground temperature all have large influences on the circula-tion near the Plateau and in East Asia.When the heating at the surface increases,the Tibetan high in the uppertroposphere intensifies,too.Its area enlarges and its axis tilts to northwest.The upper tropical easterly increase andshifts to north.The southwesterly in the lower troposphere,in consistence,also increases.The cross-equatorial low-lev-el currents along Somali and South India are influenced to increase their speeds while those over North Australia de-crease.The land low over the Asian Continent deepens.Meanwhile the upward motions over the land of east China andover the Indo-China Peninsula intensify and therefore the precipitation over those areas increases.However,along thecoastal area of China the upward motions and therefore the precipitation decrease.Atmospheric heat source anomaly has large influence on the circulation,too.Simulated results indicate that heatsource anomaly in the lower atmosphere over the Plateau influences the intensity and the position of the monsoon circu-lation while that in the upper atmosphere only affects the intensity.The heating status over the Plateau has slight influ-ence on the westerly jet,north of the Plateau,while it has strong effect on the subtropical jet at the mid and low latitudes.     

北京大庄科花岗质杂岩体中包体定位的动力学机理之探讨

北京大庄科花岗杂岩普遍含有微粒—细粒暗色包体,其中石英闪长岩和石英二长岩含包体较多,二长花岗岩含少量包体,淡色花岗岩和闪长岩含包体甚少。在含包体较多的岩体内,包体在岩体中部的分布量较多。计算结果表明,包体越小沉浮半径愈大、参数F值愈小的岩体,含包体愈多;岩体内岩浆上升速度大、包体下沉速度小以及F值小的部位,包体滞留量大。各岩体包体分布的多少,是由包体在寄主岩浆内的扩散系数、混合程度、岩浆携带力和基性岩浆混入量等因素综合决定的。