Ca, Al-rich inclusions in Yamato 791717 (CO3) carbonaceous chondrite: Formation and alteration

In three polished thin sections of Yamato 791717 (CO3). fifty-five Ca, Al-rich inclusions were found, which include two hibonite-bearing, eight melilite-rich and forty-five spinel-pyroxene inclusions. Based on the petrography and mineral chemistry of the inclusions, it is proposed that the melilite-rich inclusions and spinel-pyroxene inclusions condensed in the solar nebula, and the hibonite-bearing inclusions crystallized from melts. The heavy alteration of the inclusions in Yamato 791717, which probably took place under a very oxidizing condition in the solar nebular, is also confirmed. Project supported by the National Natural Science Foundation of China (Grant No. 49673200). and by the Japanese Society for Promotion of Sciences (JSPS).     

A new aspect of condensation theory

This paper examines the effects of the mixing of dry air into a cloud top from the point of view of the droplet spectra. It is shown theoretically that the resulting cycling of the air up and down in the cloud, as seems to be the essential mechanism by which cumuli have been diluted to their observed liquid water mixing ratio, can double the largest drop radius and generate cloud parcels containing drops of all sizes up to this maximum. These changes in the droplet distribution with size occur by a process which is not greatly influenced by the cloud condensation nuclei or the details of droplet growth since maritime like spectra can develop in continental type cumuli. It shows that large numbers of cloud condensation nuclei should not have much effect in inhibiting the rainforming process by reducing coalescence growth. On the contrary, the controlling parameters which determine precipitation efficiency and times seem to be those which control the mixing.     

西太平洋副热带高压中期变化的数值试验 Ⅰ.青藏高原热源的作用

用一个全球谱模式作数值试验研究了１９７９年６月中旬一次西太平洋副热带高压西伸北进的中期天气过程中青藏高原热源的作用。结果表明：高原的热力作用主要表现在对副高北侧锋区的形成、锋区瓣强度以及与锋区对应的对流层中上层西风急流的强度有较大的影响,有高原热力作用时,锋眍和西风流的强度都强,反之则很弱;另外还发现青藏高原感热和潜热作用是相互依赖的,在一定的天气过程中,弧立起来讨论其各自的相对重要性不太合符实际     

NUMERICAL EXPERIMENT OF MEDIUM-RANGE CHANGE OF THE SUBTROPICAL HIGH Ⅰ. THE INFLUENCE OF THE HEATING SOURCE OVER TIBET PLATEAU

The medium-range change of the subtropical high of June 1979 and its influences of the heating sources over Tibet Plateau are studied by using a global circulation spectrum-model. The analyses of the simulation results show that the heating sources over Tibet Plateau play an important role in the process of frontogenesis. the intensity of frontal zone and the upper-tropospheric westerly jet associated with it. When there are heating sources over Tibet Plateau. both the frontal zone and westerly jet are stronger. There are very important mutual relations between the sensible heating and latent heating. After the sensible heating and latent heating are isolated.it departs much from reality that the significance of them are studied     

Experimental study and constitutive modelling of elasto‐plastic damage in heat‐treated mortar

This study investigates the effect of a heat‐treatment upon the thermo‐mechanical behaviour of a model cement‐based material, i.e. a normalized mortar, with a (w/c) ratio of 0.5. First, a whole set of varied experimental results is provided, in order to either identify or validate a thermo‐mechanical constitutive model, presented in the second paper part. Experimental responses of both hydraulic and mechanical behaviour are given after different heating/cooling cycling levels (105, 200, 300, 400^°C). The reference state, used for comparison purposes, is taken after mass stabilization at 60^°C. Typical uniaxial compression tests are provided, and original triaxial deviatoric compressive test responses are also given. Hydraulic behaviour is identified simultaneously to triaxial deviatoric compressive loading through gas permeability K_gas assessment. K_gas is well correlated with volumetric strain evolution: gas permeability increases hugely when ε_v testifies of a dilatant material behaviour, instead of contractile from the test start. Finally, the thermo‐mechanical model, based on a thermodynamics approach, is identified using the experimental results on uniaxial and triaxial deviatoric compression. It is also positively validated at residual state for triaxial deviatoric compression, but also by using a different stress path in lateral extension, which is at the origin of noticeable plasticity. Copyright © 2009 John Wiley & Sons, Ltd.     

Ultrasonic-assisted condensation of chitosan with salicylaldehyde

In order to synthesize an improved adsorbent for heavy metal ions, we studied the condensation reaction of chitosan with salicylaldehyde in ethanol to form a Schiff base. The effect irradiating the reaction using an ultrasonic liquid processor was contrasted with conventional methods. The IR spectra of condensed chitosan prepared by the two methods showed that their molecular structures were identical. The reaction conditions, including solvents, ultrasonic power density and irradiation time, pH, and reactant ratio, were optimized by orthogonal design. A shorter reaction time and a higher product yield were obtained using ultrasonic-assisted synthesis compared with the traditional method. A condensation degree of 89.63% was achieved using the optimized conditions: i.e. ultrasonic irradiation at 180 W for 60 min; 95% ethanol as the solvent, pH 4.0, and salicylaldehyde:chitosan ratio of 6:1.     

大气热源年代际异常与20世纪70年代末期东亚夏季风年代际减弱

利用1958-2001年ERA-40再分析资料计算大气热源,统计分析了亚洲季风区及其邻近海域大气热源年代际变异的典型模态;利用线性斜压干模式,模拟了夏季大气对大气热源年代际异常的响应,揭示了大气热源年代际异常与1970s末期东亚夏季风年代际减弱的关系。结果表明:近50 a来亚洲及其邻近海域夏季整层大气热源变异主要表现为年代际变化特征,其年代际位相转换发生在1970s中后期,这与东亚夏季风年代际减弱的时间一致;菲律宾附近海域和中国西南地区是与东亚夏季风年代际减弱有直接联系的两个热源异常关键区;东亚夏季风年代际减弱最直接地表现为这两个关键区热源异常的共同作用,而赤道中东太平洋、赤道印度洋大气热源增强则通过大气遥响应机制影响菲律宾附近海域低层大气环流异常对东亚夏季风变异起相反的贡献。     

南亚高压在中南半岛上空建立过程及其与亚洲南部夏季风建立的关系

利用NCEP(National Centers for Environmental Prediction)/NCAR(National Center for Atmospheric Research)再分析资料, 首先讨论了南亚高压在中南半岛上空建立日期的定义标准及其建立过程。结果表明, 南亚高压在中南半岛上空建立的日期平均为4月29日;合成的南亚高压建立前后的大气环流和非绝热加热的演变揭示出南亚高压建立始于菲律宾东南洋面上的反气旋环流分裂后, 西中心在中南半岛上空建立加强形成南亚高压, 该建立过程与中南半岛非绝热加热作用密切相关。在此基础上结合NOAA(National Oceanic and Atmospheric Administration)的对外长波辐射(OLR)资料分析了南亚高压在中南半岛上空的建立与亚洲夏季风建立的关系。结果表明, 中南半岛夏季风建立和南亚高压在半岛上空建立几乎同时发生;南亚高压在中南半岛建立几天后, 东孟加拉湾夏季风开始建立;南亚高压建立大约20天后, 南海和菲律宾夏季风开始建立;大约一个月后, 西孟加拉湾、印度半岛和东阿拉伯海的夏季风建立。南亚高压在中南半岛上空的建立可视为亚洲夏季风建立的开始, 其对亚洲夏季风爆发有很好的指示意义。     

BJ-RUC产品在小区供暖供回水温度预报的应用研究

利用气象部门快速更新的BJ-RUC(Beijing-Rapid UpdateCycle)数值预报系统获得的24 h逐时的室外温度预报资料,应用能量平衡原理,建立建筑物热损失方程和供热量方程,从而推导出室外温度和室内温度、供水、回水温度的预报模型。用此模型对2010年3月1—15日期间的供、回水温度进行预报模拟,与北京市海园物业供热单位实况值进行对比分析。检验结果表明,该模型模拟的室内温度与设计要求的室内温度(20℃)之间的均方根误差为0.25℃,海园物业室内温度监测点数值与20℃之间的均方根误差为1.53℃。模拟的供、回水温度与海园物业监测点供水温度的均方根误差分别为3.69℃和3.80℃。