河北北部2005年前强震危险性预测研究

从信息论及贝叶斯模型出发,以长期异常背景为基础,近期异常为依据,在对未来十年Ｒ度的地震趋势进行估计的条件下,预测了河北北部２００５年前强震危险性,给出了区域内强震发生和各裂度概率的空间分布。     

莫来石陶瓷在电学和光学中的应用研究

莫来石在电子,光学和高温结构中的应用已广泛以受到关注。本文介绍了以电子基板材料和红外辐射材料为应用背景下,有关莫来石基陶瓷的组成与性能间的关联研究,显示了新型莫来石材料在这些应用领域的潜在优良和良好的应用前景。     

中朝边境地区新生代火山岩系对比

通过对比中国长白山区和朝鲜白头山区新生代火山岩系的层序和同位素年代学资料,首次编制出中朝边境地区新生代火山岩系分布图和新生代火山喷发阶段对比表。其岩石化学和地球化学演化趋势表明,该区新生代火山完全有可能再次喷发。     

地震的感应磁效应（二）

本文是“地震的感应磁效应（一）--三维电磁感应的数值理论”一文的继续。首先从理论和实际计算两个方面证明了三维电磁感应数值方程解的唯一性、收敛性和稳定性,从而充实了作为研究地壳、上地幔电性结构横向不均匀性理论基础的“三维数值方法”。作为这一理论方法的实际应用,文中对不同源场周期和具有不同埋藏深度的三维电导率异常体进行了模拟计算,以研究地震感应磁效应的大小、空间分布特征和频率特性。模拟计算结果表明,对于周期从数秒到数分钟的地磁短周期变化,若电导率异常体的线度与5至7级地震的震源体积大体相当,其电导率较原背景电导率高近一个量级,其感应磁效应主要特征为:在异常体正上方,地面磁场的水平分量变化最大,相对变化量约30％;在异常体于源场方向一致的两侧,垂直分量变化最大,相对变化量约40-50％。因此,观测短周期地磁场的异常变化,有可能是监测地震孕育过程地下电性变化的一种试验途径。但由于上述异常强度在空间上衰减迅速,所以观测必须接近震源区,这对测点的选择是个不利的因素。     

影响断层带再活动的一些因素的实验研究

很多地震发生在活动断层上。但断层带是否活动并不是一成不变的。目前,在没有大量实测资料的情况下,我们往往还要推断哪些断层是易于活动的。实验与计算结果表明,影响断层再活动的因素为力的方向、力的大小,断层带厚度,断层带物质的力学性质等。这些结果将有助于我们推测活断层。     

半拉格朗日方法在全球原始方程模式中的实现

简单介绍了半拉格朗日平流方案的基本概念,并详细总结了基估全球原始方程模式,特别是在ＩＦＳ的具体实现过程,拉格朗日平流的观点是着流体质点看流体运动,基贩关键是流体轨迹的计算。轨迹中点和起始点水平坐标的示得可以利用球面三角,直接在球极坐标中进行,并采用一些较高的近似。为了充分获得半拉格朗日方案析益处,在起始点的内插能工巧匠春阶数至少应在四阶以上,为避免昂贵的三维三次内插,可以采用三维“准三次”内插 。     

Delineation of spatial redox zones using discriminant analysis and geochemical modelling in arsenic‐affected alluvial aquifers

This study characterized the redox conditions in arsenic‐affected groundwater aquifers of the Lanyang plain, Taiwan. Discriminant analysis was adopted to delineate three redox zones (oxidative, transitional and reductive zones) in different aquifers and yielded 92·3% correctness on groundwater quality data. Arsenic is mainly distributed in the reductive zone, and arsenic distribution in the shallow aquifer is mainly affected by surface activities. According to PHREEQC modelling results, possible mechanisms for arsenic release to groundwater in Lanyang plain are explored. Arsenic released to groundwater in the oxidative zone (zone 1) is primarily caused by the oxidations of arsenic‐bearing pyrite minerals, and arsenate is the predominant species. While the reductive dissolution of Fe‐oxides are responsible for the high arsenic concentration found in the transitional and reductive zones (zones 2 and 3), arsenite is the predominant species. The reduction potential of groundwater rises as the depths and zones increase. Some sulphates may be reduced to form sulphide ions, which then react with arsenic to form arseno‐sulphide deposits (such as realgar, orpiment) and then slightly lower groundwater arsenic concentrations. A conceptual diagram which summarized the possible release processes of arsenic in different redox zones along groundwater flow in Lanyang plain is postulated. Arsenic‐bearing pyrite and arsenopyrite (FeAsS) are oxidized as they are exposed to the infiltrated oxygenated rainwater, releasing soluble arsenate Fe(II) and SO₄^2? into zone 1. The dissolution of arsenic‐rich Fe‐oxides due to the onset of reducing conditions in zones 2 and 3 is responsible for the mobility of arsenic and likely to be the primary mechanism of arsenic release to groundwater in the Lanyang plain Copyright © 2007 John Wiley & Sons, Ltd.     

1992—2007全球海平面变化

引起全球海平面变化的因素是复杂多样的，大气压、风、大洋环流以及海水密度的变化，都会引起海平面在时间、空间上的变化，而海水温度的变化是海平面变化的主要原因。该文利用法国Archiving, Validation and Interpretation of Satellite Oceanographic data（AVISO）的海表面高度异常数据，计算了1992年10月至2007年1月间，全球海平面的平均上升速度，同时详细解算海平面上升速度的全球空间分布，分析全球海平面的变化趋势并将海平面变化同美国国家海洋大气署（NOAA）的Optimum Interpolation Sea Surface Temperature （OISST）海表面温度数据进行了比对和相关分析。     

A new soil freeze/thaw discriminant algorithm using AMSR‐E passive microwave imagery

The soil freeze–thaw controls the hydrological and carbon cycling and thus affects water and energy exchanges at land surface. This article reported a newly developed algorithm for distinguishing the freeze/thaw status of surface soil. The algorithm was based on information from Advanced Microwave Scanning Radiometer Enhanced (AMSR‐E) which records brightness temperature (Tb) in the afternoon and after midnight. The criteria and discriminant functions were obtained from both radiometer observations and model simulations. First of all, the microwave radiation from freeze–thaw soil was examined by carrying out experimental measurements at 18·7 and 36·5 GHz using a Truck‐mounted Multi‐frequency Microwave Radiometer (TMMR) in the Heihe River of China. The experimental results showed that the soil moisture is a key component that differentiates the microwave radiation behaviours during the freeze–thaw process, and the differences in soil temperature and emissivity between frozen and thawed soils were found to be the most important criteria. Secondly, a combined model was developed to consider the impacts of complex ground surface conditions on the discrimination. The model simulations quite followed the trend of in situ observations with an overall relation coefficient (R) of approximately 0·88. Finally, the ratio of Tb18·7H (horizontally polarized Tb at 18·7 GHz) to Tb36·5V was considered primarily as the quasi‐emissivity, which is more reasonable and explicit in measuring the microwave radiation changes in soil freezing and thawing than the spectral gradient. By combining Tb36·5V to indicate the soil temperature variety, a Fisher linear discrimination analysis was used to establish the discriminant functions. After being corrected by TMMR measurements, the new discriminant algorithm had an overall accuracy of 86% when validated by 4‐cm soil temperature. The multi‐year discriminant results also provided a good agreement with the classification map of frozen ground in China. Copyright © 2011 John Wiley & Sons, Ltd.     

Mkn501长期光变性质

在R和I波段对Mkn 501进行了测光观测,并结合历史文献得到Mkn 501在近30年间的光学、红外和射电等多个波段的光变曲线;讨论了光变与色指数之间的关系,发现色指数(B—V)与(B—R)之间有强相关,相关系数r=0.73.利用DCF方法分析了多波段光变的相关性,发现B波段与4.8GHz和红外波段的光变存在一定的正相关,利用CLEANest方法对B波段的光变曲线进行频谱分析,结果表明Mkn 501的光变曲线存在2个可能的周期,即(10.06±0.04)年和(21.60±0.17)年.