基于数字滑坡技术的暴雨滑坡、泥石流预警、监测模型研究

中国学者在暴雨滑坡、泥石流预测预报研究领域取得的成果为采用数字滑坡技术进行暴雨滑坡、泥石流预警、监测模型研究提供了宝贵的基础,应用数字滑坡技术建立暴雨滑坡、泥石流预测模型的原则是：（1）必须在滑坡、泥石流形成条件理论指导下;（2）应了解研究区地质环境及滑坡、泥石流特征;（3）就基于数字滑坡技术而言,只能选取遥感方法可能...     

太湖流域某地区浅层地下水有机污染特征

对太湖流域某地区浅层地下水有机污染特征进行了总结，并就污染来源、污染途径和典型污染源附近浅层地下水有机污染特征等问题进行了研究。研究结果表明，该地区浅层地下水中各组分的检出率较高，但检出浓度较低，除苯在个别采样点处超出美国环保局（EPA）饮用水标准外，其余卤代烃和单环芳烃组分均没有超标；平面分布上，卤代烃和单环芳烃各组分的浓度高值点大都集中于该地区东南部的工业区内，这种空间分布特征与工业区的分布具有明显的一致性；垂向上有浅部地下水的污染程度相对较重、深部地下水较轻的特点；典型污染源周边浅层地下水的污染程度较重，但随着采样点远离污染源，地下水中各有机污染组分的浓度迅速衰减。     

铊的环境地球化学研究进展及铊污染的防治对策

铊是分散元素,具剧毒性,对环境危害严重。本文就国内外近年来对铊的生态危害、铊在环境介质如岩(矿)石、土壤、水体和动植物中的分布和迁移等方面的研究进展和存在的主要问题进行了综述,初步提出了防治铊污染的相关对策。     

福建龙湖40多年来环境地质演化及其警示

本文首次报道福建境域湖泊沉积物中有毒元素含量的变化。根据对晋江市龙湖 4 0多年来沉积柱的环境地质演化的研究 ,发现其污染度自 1976～ 2 0 0 2年呈急速上升态势。其中上升最快的元素为 Cd、Hg、As、Pb、Cu、Zn、Cr,尤以 Cu最为典型 ,其污染度变化可分为三个时段 :11976～ 1984年污染指数 0 .6 7,为微污染 ;21984～ 1993年污染指数 0 .86 ,为轻污染 ;31993～ 2 0 0 2年污染指数 2 .37,为重污染。第二时段的污染度为第一时段的 1.3倍 ,第三时段的污染度为第一时段的 3.5倍。表明污染度增加是十分迅速和严峻的。值得引起我们高度关注的是 ,1984～ 2 0 0 2年 ,19年间龙湖中剧毒元素 Hg、As、Pb的平均含量均超越国家标准 ,为污染环境。 2 0 0 2年 4月龙湖表面沉积中这 3种剧毒元素分别为 1976～ 1984年时段含量最低值的 4 6 .3倍、3.3倍、1.9倍 ,已大大超过其“警戒线”(如 Hg为标准值的 4 .4倍 ) ,显示龙湖污染的严重性。龙湖环境地质条件的日益恶化 ,对人群健康已造成一定影响 (如癌症病人日益增加 ) ,这也警示着日本水俣病可能在该地区重演     

Radio observations of the 1968 September solar eclipse

This paper summarizes the analysis of the radio observations of the solar eclipse at wavelengths 3.2, 11.1 and 21 cm in Xinjiang, on 1968 Sept. 22. From the observations, we have determined the flux densities, angular diameters and heights of the localized radio sources on the solar disk, circumstances of the radio eclipse, equivalent radius of the radio Sun and certain features of a small radio burst that occurred during the eclipse. We have also investigated the correlation between the flux density of the localized sources and the activity of the active regions, as measured by the integrated brightness of plages and the sunspot area.     

2000年7-8月台湾海峡南部至珠江口附近海域表层温、盐度分析

根据表层温、盐度的观测结果，结合相关断面的CTD调查资料和同期的卫星遥感海表温度图，分析了2000年7月10日到8月2日台湾海峡南部至珠江口附近海域的一些海洋现象，结果表明：(1)在调查期间，东山至惠来沿岸海域存在明显的低温高盐区，海丰和惠来以南近岸海域的海水也具有相对高盐的性质，说明调查期间在闽南、粤东沿岸普遍存在上升流现象；(2)调查期间在台湾海峡南部至珠江口之间陆架—陆坡区附近的多个断面上观测到了较明显的盐度锋面；(3)珠江口外的盐度锋面的位置随时间而不断变化。     

Marine disaster prevention and integrated coastal zone management

1 MAJN CHARAcrERISTICS OF MARINE DISA5TEROwing to marine natural environment anomaly and imense changr, alI those disastersthat cause Peoples life and propedy loss over the sea aod coast area are called marinedisasters. China is a country with big sea area, of coast line l8000 km length, precinctsea area 3,000,000 km', more than 6500 islands bigger than 500 m2 with coast line of allislands 14000 km length. The Pacific Ocean is ocean with the most frequent marine disasters,further…     

基于GOCE梯度的地球引力场恢复(英文)

Given the second radial derivative Vr r ( P ) |S of the Earth’s gravitational potential V ( P ) on the surface S corresponding to the satellite altitude, by using the fictitious compress recovery method, a fictitious regular harmonic field rrVr r( P )* and a fictitious second radial gradient field Vr *r ( P) in the domain outside an inner sphere K i can be determined, which coincides with the real field Vr r( P ) in the domain outside the Earth. Vr *r ( P)could be further expressed as a uniformly convergent expansion series in the domain outside the inner sphere, because rrVr r( P )* could be expressed as a uniformly convergent spherical harmonic expansion series due to its regularity and harmony in that domain. In another aspect, the fictitious field V * ( P) defined in the domain outside the inner sphere, which coincides with the real field V ( P ) in the domain outside the Earth, could be also expressed as a spherical harmonic expansion series. Then, the harmonic coefficients contained in the series expressing V * ( P) can be determined, and consequently the real field V ( P ) is recovered. Preliminary simulation calculations show that the second radial gradient field Vr r( P ) could be recovered based only on the second radial derivative Vr r ( P )| S given on the satellite boundary. Concerning the final recovery of the potential field V ( P ) based only on the boundary value Vr r ( P )|S, the simulation tests are still in process.     

地球的时变主惯性矩和变化的自转(英文)

Based on the gravity field models EGM96 and EIGEN-GL04C, the Earth's time-dependent principal moments of inertia A, B, C are obtained, and the variable rotation of the Earth is determined. Numerical results show that A, B, and C have increasing tendencies; the tilt of the rotation axis increases 2.1×10-8 mas/yr; the third component of the rotational angular velocity, ω 3, has a decrease of 1.0×10-22 rad/s2, which is around 23% of the present observed value. Studies show in detail that both θ and ω 3 experience complex fluctua-tions at various time scales due to the variations of A, B and C.     

Spatial-temporal characteristics of epidemic spread in-out flow——Using SARS epidemic in Beijing as a case study

For better detecting the spatial-temporal change mode of individual susceptible-infected-symptomatic-treated-recovered epidemic progress and the characteristics of information/material flow in the epidemic spread network between regions,the epidemic spread mechanism of virus input and output was explored based on individuals and spatial regions.Three typical spatial information parameters including working unit/address,onset location and reporting unit were selected and SARS epidemic spread in-out flow in Beijing was defined based on the SARS epidemiological investigation data in China from 2002 to 2003 while its epidemiological characteristics were discussed.Furthermore,by the methods of spatial-temporal statistical analysis and network characteristic analysis,spatial-temporal high-risk hotspots and network structure characteristics of Beijing outer in-out flow were explored,and spatial autocorrelation/heterogeneity,spatial-temporal evolutive rules and structure characteristics of the spread network of Beijing inner in-out flow were comprehensively analyzed.The results show that(1)The outer input flow of SARS epidemic in Beijing concentrated on Shanxi and Guangdong provinces,but the outer output flow was disperse and mainly includes several north provinces such as Guangdong and Shandong.And the control measurement should focus on the early and interim progress of SARS breakout.(2)The inner output cases had significant positive autocorrelative characteristics in the whole studied region,and the high-risk population was young and middle-aged people with ages from 20 to 60 and occupations of medicine and civilian labourer.(3)The downtown districts were main high-risk hotspots of SARS epidemic in Beijing,the northwest suburban districts/counties were secondary high-risk hotspots,and northeast suburban areas were relatively safe.(4)The district/county nodes in inner spread network showed small-world characteristics and information/material flow had notable heterogeneity.The suburban Tongzhou and Changping districts were the underlying high-risk regions,and several suburban districts such as Shunyi and Huairou were the relatively low-risk safe regions as they carried out minority information/material flow.The exploration and analysis based on epidemic spread in-out flow help better detect and discover the potential spatial-temporal evolutive rules and characteristics of SARS epidemic,and provide a more effective theoretical basis for emergency/control measurements and decision-making.