0604号强热带风暴"碧利斯"特大暴雨的诊断研究

利用地面加密观测资料、自动站降水量资料和NCEP 1°×1°的每6 h再分析等资料,从能量、热量、水汽量以及环境场、冷空气和地形作用,分析了0604号强热带风暴"碧利斯"造成华南6省区大范围的强暴雨过程。结果表明:西太平洋副热带高压和大陆高压合并、西南季风异常活跃、高空强辐散流场和弱垂直切等均变有利于碧利斯陆上维持不消,越赤道气流致使西南季风强盛并将孟加拉湾和南海的水汽源源不断输入强暴雨区。分析发现:(1)风暴区域能量主要依靠潜热能平流的输送,维持暖性结构和产生强降雨;造成台风剧烈天气的动能是由非地转风穿越等压线,大气斜压性增强所制造的。(2)垂直输送项造成Q1和Q2的异常,是低层暖湿气流被抬升到高层产生凝结和潜热释放所造成的,积云对流所释放的凝结潜热对台风环流的反馈作用在台风暴雨中起到十分重要的作用。(3)冷空气从风暴东西两侧向低层嵌入,触发对流运动发展,近地层涡度和散度的形变项使山区处于一涡源状态,不断触发中尺度降水系统,促使暴雨增幅。     

福建地区中小地震加速度反应谱衰减规律

本文基于收集福建省地震监测台网7个基岩台站从1999年至2007年获得的94个地震(ML=2.8～4.9,△=13～462 km) 的1974条宽频带速度记录,利用实时仿真方法得到了相应的加速度记录,进而得到了福建地区基岩场地中小地震绝对加速度反应谱的衰减关系.对基岩反应谱有影响的因素主要有震源、传播途径,本文简要分析这两个因素对地震动的影响.此项工作对于福建省抗震设防具有重要的意义.     

利用GRACE卫星数据研究汶川地震前后重力场的变化

介绍了利用GRACE卫星数据计算和分析重力场变化的方法.以EIGEN-GRACE02S重力场模型为背景,对高斯平滑处理前后中国大陆月重力场的变化作了比较,认为取平均半径为666 km作高斯平滑,能够得到合理的重力变化结果.以3个月时间尺度计算了2008年汶川地震前后中国大陆的重力场变化,将结果与2006年和2007年相同时间尺度的变化结果进行比较,发现三者相符合,并且同震重力的负变化可用地壳膨胀模型理论来解释.     

一种基于微博签到数据的城市功能区复合程度探究方法

城市功能区复合程度是城市发展规划、评价城市区域发展均衡性的重要参考.本文以深圳市为研究对象,首先,划分渔网单元与微博签到数据求交计算样方单元各类签到数据比例.其次,采用香农熵对复合程度进行定量化描述并连接渔网赋予属性值.最后,基于ArcGIS由粗至细进行可视化呈现和分析.结果表明,提出的方法能够有效地表示城市功能区的复...     

塔里木盆地奥陶系形成大油气田地质条件

自１９８４年９月地矿部在塔北沙参２井奥陶系油气勘探首次取得重大突破后,又在塔北、塔中、塔西南相继获得发现或突破,形成了第一轮以奥陶系为重点的油气勘探热潮。虽在１９９１～１９９５年由于认识上的影响一度出现油气勘探低谷,但从１９９６年开始又迎来了新一轮塔里木盆地奥陶系油气勘探的新高潮。多年油气勘探实践和研究表明,塔里木盆地奥陶系油气资源潜力相当巨大,具备形成大油气田的条件,是塔里木盆地今后寻找大油气田的主要层位之一。     

Expression of Mammalian Metallothionein-I Gene in Cyanobacteria to Enhance Heavy Metal Resistance

Metallothionein (MT) from mammals is a low molecular weight (about 6–7 KD), and cystein-rich (20 cystein per molecular) protein (Vallee, 1991). So MT has the strong binding ability of metal such as Cd, Hg and Pd. Wild-typed cyanobacteria have their own metallothionein-like proteins, which are of low cysteine content and have weak ability to bind heavy metal. Therefore, it is imperative to transfer the MT-I gene from mammal into cyanobacteria cell for the absorption and accumulation of heavy metals in aqueous system including marine and lake ( Misra and Gedamu, 1989). We inserted the MT-I cDNA gene after the strong promoter PpsbA or Psmt into the intermediary vector pRL-439, and then pRL-MT was ligated with shuttle vector pKT-210 (a shuttle vector pDC-08 was used at an earlier time) to construct the shuttle expression vector pKT-MT. (The MT-I mutant -KKS- also was selected as aim gene.) Then the constructed vector was introduced into cyanobacterium Anabaena sp. PCC7120, Synechocystis sp. PCC6803 and Synechococcus sp. PCC7942 with triparental conjunctive transfer (Bryant, 1994). The expression efficiency is about 1%. We also used homologous recombination vector pTZ18-8 to introduce MT-I cDNA into chromosomes in cyanobacteria and got higher expression efficiency. Metal tolerance tests show that the transgenic cyanobacteria acquire metal resistance up to 60 μmol/g CdCl₂ and expression efficiency up to 1045 μg MT/g fresh cells according to the data of ELISA.     

沁水盆地煤层气气源岩地球化学特征及气源潜力分析

对比研究了山西沁水盆地李雅庄煤矿、寺河煤矿和附城七一煤矿煤岩的地球化学特征,讨论了煤岩的热演化程度、可溶有机质含量、生物标志化合物特征。在此基础上,分析了热成因煤层气与次生生物成因煤层气的气源潜力,对研究区煤层气勘探有实际意义。      

Periodicities in the green corona for the sun as a star

A coronal index (CI) derived from the limb observations of the 530.3 nm emission corona (green corona) over 1964–1987 was analyzed by the Fourier transform technique (FTT) to find periodicity in this layer of solar atmosphere. As expected, two pronounced periods were indicated: the rotational, about 27 d, and the activity cycle length, 11 years. Beside these there are seen other periodicities of less significancies, namely of about 5,2.2,1 and 0.5 year. The values of these periodicities in individual cycles 20 and 21 slightly differs that could be related to different activity zone depths beneath the photosphere.     

高级语言中过程概念的区别

计算机高级语言很多 ,在我国不同时期语言的代表有BASIC语言、FORTRAN语言、C及C ++语言和数据库 ,而这些语言当然都有各自的特点和应用范围 ,但均有一个共同的部分 ,有些称它为子程序 ,有些称它为函数 ,有些称它为过程。因些根据多年教学经验及实践应用针对该问题在不同语言中的区别加以阐述。     

Preliminary research on the transmission path of nssSO2-4- and NO-3 in Antarctic ice sheet

The main sources of nssSO24- and NO-3 were summarized in this paper. By analyzing the spatial distribution features of major ions in Antarctic ice sheet and studying on the different time of the same volcanic event recorded by different ice cores from different regions in Antarctica, this paper intends to study the transmission path of nssSO24- and NO-3. Results show that nssSO24- and NO-3 are transmitted to the ice sheet through long distance and high altitude. The procedure of the transmission is that nssSO24- and NO-2 are transmitted to the level between the top of troposphere and the bottom of stratosphere, then subsided to the ice sheet surface and spread to other regions.