Progresses in geology and hazards analysis of Tianchi Volcano

A number of different lahars have been recognized from a systematic survey of a mapping project. The high setting temporamre feature of the deposits indicates a relationship between the lahar and the Millennium eruption event of Tianchi Volcano. The lahars caused a dramatic disaster. Recognize of the huge avalanche scars and deposits around Tianchi Volcano imply another highly destructive hazard. Three types of different texture of the avalanche deposits have been recognized. There was often magma mixing processes during the Millennium eruption of Tianchi Volcano, indicating a mixing and co-eruption regime of the eruption.     

西部调水应全面综合规划

以往的南水北调工程局限在长江流域内,没有谈到从藏东调水。西线调水的方案很多,原有的规划是在本流域内.现在是跨流域调水。到底如何选取调水目标?那些地区是真缺水?调水顺序如何?应做全面和系统的规划,规划中要有西部需水的总体规划。 对于雅鲁藏布江的调水工程也要有全面的综合规划。供水和调水区可调多少水.要从总的经济效益来评价。这应是多学科、多方面专家共同讨论的问题。     

GPS中BOC调制的FPGA实现

GPS系统中提出了一种新的信号形式,二进制偏移载波(BOC)调制是这种新的信号形式产生的技术关键。首先介绍了BOC调制的定义及其频谱特性,然后阐述了基于FPGA(现场可编程门阵列)硬件平台的BOC调制实现方法,并给出了仿真波形。结果表明,该实现方法是值得提倡的。     

八庙—青山金红石矿床化学成分与成矿关系

本矿床是我国金红石矿床重要的成因及工业类型，为具有特定化学成分的岩石在特定变质条件下形成的。本文通过对大量数据的处理，查明了化学成分与成矿的关系：高Ａｌ２Ｏ３、ＭｇＯ、Ｆｅ２Ｏ３＋ＦｅＯ、Ｋ２Ｏ、Ｐ２Ｏ５、Ｈ２Ｏ＋、ＭｎＯ，低ＳｉＯ２、ＣａＯ、Ｎａ２Ｏ、ＣＯ２、Ｓ等，利于钛富集；高ＴｉＯ２、ＭｇＯ、Ｐ２Ｏ５、Ｓ，低ＳｉＯ２、ＣａＯ、Ｋ２Ｏ、Ａｌ２Ｏ３、Ｆｅ２Ｏ３／ＦｅＯ，利于金红石形成；高Ｓｃ、Ｚｒ、Ｎｉ、Ｚｎ及Ｌａ／Ｙｂ，低Ｙ、Ｎｂ、Ｔｈ、Ｃｄ、Ｂａ、Ｂｅ、ΣＲＥＥ，利于金红石纯度提高。对研究矿床成因及寻找新的同类矿床等有重要意义     

低频扩频中伪随机序列产生方法的研究

伪随机序列的产生是实现BPC低频时码发播台扩展频谱技术升级的一个重要环节。针对BPC低频时码发播台的现有系统，提出了伪随机序列的产生方案，并对其性能作了分析。     

雾化进样石墨炉原子吸收光谱法的研究 Ⅰ.直接雾化进样装置及其性能

介绍一种自行设计和加工的直接雾化石墨炉进样装置的结构、工作原理和操作方法。该装置由微机控制与石墨炉加热程序同步工作,可以实现自动控制和自动测量。对雾化进样石墨炉分析的仪器参数和实验条件进行了研究和选择。结果表明,该装置与石墨炉结合具有自动化程度高、重现性好、样品利用率高和分析速度快等特点。     

Gamma-ray bursts: optical afterglows in the deep Newtonian phase

Gamma-ray burst remnants become trans-relativistic typically in days to tens of days, and they enter the deep Newtonian phase in tens of days to months, during which the majority of shock-accelerated electrons will no longer be highly relativistic. However, a small portion of electrons are still accelerated to ultra-relativistic speeds and are capable of emitting synchrotron radiation. The distribution function for electrons is re-derived here so that synchrotron emission from these relativistic electrons can be calculated. Based on the revised model, optical afterglows from both isotropic fireballs and highly collimated jets are studied numerically, and compared to analytical results. In the beamed cases, it is found that, in addition to the steepening due to the edge effect and the lateral expansion effect, the light curves are universally characterized by a flattening during the deep Newtonian phase.     

PKI中RA的功能模型及一种实现方式

网络安全是近年来研究的热点，各种新技术不断涌现，身份认证是安全应用中最重要的一个问题，也是PKI的核心服务之一。PKI作为信息安全的基石经过几年的发展不断走向成熟，在许多领域发挥着重要的作用。针对目前对PKI中的重要部件RA的研究很少的状况，着重对RA的实现模型进行了探讨。     

基于负反馈的网络负载调度算法

提出一种基于负反馈权值的动态网络负载调度算法。算法主要用在多出口路由器上，其执行效率高，开销小。基于算法的多出口路由器不仅能够很好的保持出口间的负载均衡。还具有良好的出口容错性能。     

Fatty Acid Composition Analyses of the DCMU Resistant Mutants of Nannochloropsis oculata (Eustigmatophyceae)

1　Introduction　Nannochloropsissp .areoneofpotentialsourcesofpolyunsaturatedfattyacids ,especiallytheeicosapen taentaenoicacid (EPA ,C2 0∶5 ) ,whichisimportantforbothanimalsandhumans .　Thefattyacidcompositionofthisalgaisaffectedbyvariousenvironmentalfactors ,suchaslightintensity(Sukeniketal.,1989;Sukeniketal.,1990 ) ,imply ingthatafactorinfluencingthephotosyntheticprocessmayaffectcellularfattyacidsynthesisandtheirmetabolism .AselectionprogramofincreasingcellularEPAcontenthasbeencarriedo…