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31.
从认知风格理论出发,顺应学习者的认知风格差异,建立多层次、一体化的实验教学体系,并从实验教学的内容、过程、环境与考核出发,构建个性化的学习平台,以培养学习者的实践能力与创新精神。  相似文献   
32.
宁夏大峰矿5500t爆破及观测研究   总被引:1,自引:0,他引:1  
2007年底在宁夏和内蒙古交界的贺兰山大峰煤矿进行了5500t的大当量工业爆破,这是一次进行地球物理、工程抗震等研究的难得机会,同时也是全面检测宁夏及邻区“十五”新建测震及前兆系统运行情况及工作状况的机会。除了加强固定测震台网的监测外,宁夏回族自治区地震局还联合甘肃,四川,青海4省地震局布设了南北向的临时测线。北京大学,中国地震局地球物理勘探中心及爆破单位等十余家单位,分别在不同地点沿不同方向布置了不同研究目的的测线。本文就此次爆破和观测情况做简要介绍。  相似文献   
33.
The low detection limits and multi‐element capability of inductively coupled plasma‐mass spectrometry (ICP‐MS) makes it an attractive option in a wide range of environmental, medical, biological, industrial and archaeological applications. Quadrupole ICP‐MS is used to determine element concentrations in a diverse range of sample types, often very different from the geological applications for which ICP‐MS was originally developed. Whilst modern instruments are robust and capable of a high degree of automation, it is essential that users of both instrumentation and data are aware of the strengths and limitations of the technique. Many people who are now involved with the operation and application of ICP‐MS instruments are not specialists in the field, as was usually the case amongst early operators. This back‐to‐basics review is aimed at the novice user and includes a guide to ICP‐MS instrumentation and performance. Whilst solids, liquids and gases can all be measured by ICP‐MS, discussion of sample introduction is limited to liquids. Requirements for producing good quality data, including aspects of sample preparation, calibration, and methods of interference limitation are also discussed.  相似文献   
34.
In the beginning of the 21st century, the Tenth Five-Year Priority Research Projects of the Earth Sciences of the National Natural Science Foundation of China (NSFC) were initiated. After nearly a two-year long process to prepare, the first version of six Priority Research Projects of Earth Sciences was published in October 2001 by NSFC, viz., Local Response to Global Changes, Life Process and Environment,Dynamics and Physical Processes in the Weather and Climate System, Continental Dynamics, Regional Sustainable Development, Solar-Terrestrial Environment and Space Weather. The process involved more than 200 renowned Chinese scientists and many departments and agencies in China. The six Priority Research Projects guide the research effort of the earth sciences for the NSFC from year 2001 to 2005.This paper provides a brief introduction to the Third Priority Research Project of the Department of Earth Sciences of NSFC-Dynamics and Physical Processes in the Weather and Climate System (DPWOS).  相似文献   
35.
This review describes developments in trace element determination using inductively coupled plasma‐atomic emission spectrometry (ICP‐AES) and inductively coupled plasma‐mass spectrometry (ICP‐MS) that were reported in 2006 and 2007. It focuses on the application of ICP techniques to geological and environmental samples; fundamental studies in ICP‐MS and ICP‐AES instrumentation have largely been ignored. New advances in ICP‐MS and ICP‐AES were incremental over this period, partly because both techniques are now well‐established. A continuing shift towards the hyphenation of low‐flow separation techniques has sparked activity in the development of appropriate low‐flow interfaces, and papers discussing interference removal also contribute significantly to the volume of research for both ICP‐AES and ICP‐MS. Whereas the majority of new ICP publications concerned advances in ICP‐MS analysis rather than ICP‐AES, development for ICP‐AES still occurs in almost all areas, particularly in sample introduction and hyphenated techniques.  相似文献   
36.
水生生态系统中的捕食与生物多样性   总被引:1,自引:0,他引:1  
捕食在水生生态系统中有重要的作用,是影响生物多样性的主要因素子之一。选择性的捕食中能使被喜食的猎物种类从水体中消失,使生物多样性降低。这种捕食也可能抑制优势种的发展,占免竞争排斥,提高猎生物多样性。  相似文献   
37.
该文对SHRIMP锆石U-Pb同位素测年方法从野外取样、碎样、矿物分选、制靶、显微照相和图片标记处理及测试进行了介绍,同时对LP-ICPMS法和TIMS法进行了简要说明。SHRIMP法对前寒武纪地质体年龄的测定具重要定年意义。  相似文献   
38.
This article reviews the literature involving benthic invertebrates that are cited in association with hull fouling, reporting the species that occur on the Brazilian coast and evaluating the importance of this vector for the introduction of nonindigenous and cryptogenic invertebrates in Brazil. It discusses some of the strategies that were used by the species that allowed for their overseas transport and made it easier to cross natural barriers that otherwise would have been obstacles to their dispersion. The compiled data list 343 species (65% nonindigenous and 35% cryptogenic), mainly from the northwestern Atlantic Ocean. The traveling fauna, composed mostly of cosmopolitan species (70.3%), is primarily euryhaline and marine stenohaline, with sessile and sedentary habits. After delineating the shipborne species’ ecological profiles and traveling strategies and evaluating their overlapping vectors, we concluded that hull vessels were the main vector of introduction to the Brazilian coast for 89.8% of the compiled species.  相似文献   
39.
李小玲 《热带地理》2014,34(1):130-132
引言是一篇学术论文让读者建立第一印象的“开门匙”,讨论是彰显文章水平和深度的标尺,故引言和讨论的写作对于一篇论文的重要性不言而喻。文章在分析已有文献的基础上,结合自己多年的编辑经验,以及与青年作者接触的感触,探析“引言”是如何围绕科学问题的提出而逐层展开,“讨论”是如何围绕科学问题的回答而循序深入;科学问题的提出和回答成为引言和讨论的核心内容,而科学问题则是连接两者的天然纽带。引言与讨论存在着前后呼应的对应关系。  相似文献   
40.
介绍广西人工影响天气信息综合管理系统的总体结构及各子系统的功能。  相似文献   
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