Studies on the Thermodynamics and Thermal Chemistry Properties for Lithium Salts and Their Aqueous Solution Systems

正1 Introduction With the industrial development of lithium battery,nuclear and aerospace industry,the demands of metal lithium and its compounds are increasing significantly.Lithium is called as the energy of the metal in the new century(Zhang et al.2001).The total reserve of lithium resources around the world7     

Recent Progresses in Comparative Planetology——Summary of the Session of Comparative Planetology at the 3rd Conference of Earth System Sciences

Comparative planetology is an interdisciplinary science between Earth sciences and astronomy. It studies physical, chemical and dynamical properties of planets and satellites and their surface characteristics, interior structures and chemistry, magnetic field, climate and possible existence of life. Although the study of comparative planetary science is at its infancy stage in China, it is very encouraging to see that 25 papers were received by the session, which is much more than what we expected. It indicates that more and more scientists are interested in this research field. These papers can be classified into three categories: solar planets, extra-solar planets, and moon explorations. Scientists from both China and oversea reported their recent results.     

GPS历元比较时间对齐方法

基于“齿轮转动”思想,本文设计了对GPS历元时间对齐比较的方法,实现了两个GPS历元文件各历元准确遍历自动查询,有效解决了历元比较时间对齐耗时、费力问题;通过文件两两比较可实现三文件比较,该方法查询速度快、省时简便,同时为其他具有相同特性的数据比较提供了很好的经验,具有较好的实际应用价值。     

Using a H∞ filter assimilation procedure to estimate root zone soil water content

Root zone soil water content impacts plant water availability, land energy and water balances. Because of unknown hydrological model error, observation errors and the statistical characteristics of the errors, the widely used Kalman filter (KF) and its extensions are challenged to retrieve the root zone soil water content using the surface soil water content. If the soil hydraulic parameters are poorly estimated, the KF and its extensions fail to accurately estimate the root zone soil water. The H‐infinity filter (HF) represents a robust version of the KF. The HF is widely used in data assimilation and is superior to the KF, especially when the performance of the model is not well understood. The objective of this study is to study the impact of uncertain soil hydraulic parameters, initial soil moisture content and observation period on the ability of HF assimilation to predict in situ soil water content. In this article, we study seven cases. The results show that the soil hydraulic parameters hold a critical role in the course of assimilation. When the soil hydraulic parameters are poorly estimated, an accurate estimation of root soil water content cannot be retrieved by the HF assimilation approach. When the estimated soil hydraulic parameters are similar to actual values, the soil water content at various depths can be accurately retrieved by the HF assimilation. The HF assimilation is not very sensitive to the initial soil water content, and the impact of the initial soil water content on the assimilation scheme can be eliminated after about 5–7 days. The observation interval is important for soil water profile distribution retrieval with the HF, and the shorter the observation interval, the shorter the time required to achieve actual soil water content. However, the retrieval results are not very accurate at a depth of 100 cm. Also it is complex to determine the weighting coefficient and the error attenuation parameter in the HF assimilation. In this article, the trial‐and‐error method was used to determine the weighting coefficient and the error attenuation parameter. After the first establishment of limited range of the parameters, ‘the best parameter set’ was selected from the range of values. For the soil conditions investigated, the HF assimilation results are better than the open‐loop results. Copyright © 2010 John Wiley & Sons, Ltd.     

一种基于短时傅立叶变换的脉冲星消色散算法

叙述了一种基于短时傅立叶变换的脉冲星消色散算法。首先介绍了脉冲星的色散形成原因以及几种当今流行的消色散算法。接着介绍了短时傅立叶变换,并在此基础上提出了一种基于短时傅立叶变换的消色散算法。然后详细讲述了这种消色散算法的具体实现步骤,并且比较了在选取不同长度的时间窗函数的情况下,消色散的处理过程和残余色散量。最后,通过将这种算法的计算量以及结果和其他几种算法做横向比较,得出了结论:这种消色散算法的计算量小,实现简单,可以有效的进行消色散处理。     

THE CORRESPONDING ANALYSIS OF HEAVY-METAL POLLUTION OF SOIL IN ZHUZHOU CITY

ＴＨＥ ＣＯＲＲＥＳＰＯＮＤＩＮＧ ＡＮＡＬＹＳＩＳ ＯＦ ＨＥＡＶＹ－ＭＥＴＡＬ ＰＯＬＬＵＴＩＯＮ ＯＦ ＳＯＩＬ ＩＮ ＺＨＵＺＨＯＵ ＣＩＴＹ ＳｈａｎｇＪｉｎｃｈｅｎｇ（尚金城）；ＬｏｎｇＡｉｍｉｎ（龙爱民）ＬｉＢｉｎ（李斌）；ＪｉａｎｇＪ...     

阿尔泰南缘地球物理场特征与矿床分布规律

通过对新疆阿尔泰南缘地球物理场特征-深部构造-已知大型矿床分布规律的系统研究,认为该地区不同属性的地质块体受3组基底构造控制,即EW向、NE向和NW向3组基底构造系,并认为该地区已知大型-超大型矿床同样受这3组深部构造系的控制.最后对阿尔泰地区进行了大型、超大型多金属矿床成矿预测.     

BDS/GPS双系统组合GBAS性能评估

随着北斗卫星导航系统(BDS)全球组网进程的推进,BDS/GPS组合导航成为提高导航性能的重要方法,同时地基增强系统(GBAS)作为实现精密导航的新一代导航方式是当前研究的热点。本文通过推导BDS/GPS双系统组合GBAS数学模型,分别对BDS、GPS独立作为GBAS导航源及BDS/GPS组合导航作为GBAS导航源时系统的精度因子(DOP)、垂直保护级(VPL)性能进行了对比分析,对比验证了应用各系统时GBAS性能的差异。结果表明,基于BDS与GPS的GBAS性能接近,且互有优势;BDS/GPS组合GBAS性能优于各单系统性能。