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41.
何霆 《华南地震》2012,(3):107-117
广东省12322防震减灾公益服务平台在2009年正式开通后,经过几次中小型地震的检验,系统暴露出很多不足之处,包括对现有资源的利用率不高、平台对专业技术人员和社会民众的服务能力不足等。通过改进系统现有的服务模式,提供更多实用的服务功能,如信息收集、短信群发、交互式服务和统计分析等,以便更好地服务社会民众,在应急事件中发挥更大的功用。  相似文献   
42.
There are awareness and concerns caused by the decreasing sea ice coverage around the Arctic and Antarctic due to effects of climate change. Emphasis in this study was on rapid changes in Arctic sea ice coverage and its impacts on the marine ecology during the fourth Chinese National Arctic Research Expedition in 2010. Our purpose was to establish a baseline of Arctic fish compositions, and consequent effects of climate change on the fish community and biogeography. Fish specimens were col- lected using a multinet middle-water trawl, French-type beam trawl, otter trawl, and triangular bottom trawl. In total, 36 tows were carried out along the shelf of the Bering Sea, Bering Strait, and Chukchi Sea in the Arctic Ocean. in total, 41 fish species belonging to 14 families in 7 orders were collected during the expedition. Among them, the Scorpaeniformes, including 17 species, accounted for almost one third of the total number (34.8%), followed by 14 species of the Perciformes (27.0%), 5 species of the Pleuronecti- formes (22.3%), and 2 species of the Gadiformes (15.4%). The top 6 most abundant species were Hippoglossoides robustus, Bore- gadus saida, Myoxocephalus scorpius, Lumpenus fabricii, Artediellus scaber, and Gymnoeanthus trieuspis. Abundant species var- ied according to the different fishing methods; numbers of families and species recorded did not differ with the various fishing methods; species and abundances decreased with depth and latitude; and species extending over their known geographic ranges were observed during the expedition. Station information, species list, and color photographs of all fishes are provided.  相似文献   
43.
A performance test was conducted in a wind tunnel by changing the principal configuration parameters of a sampler such as the diameter of the container, inlet width and cone height. The results show that the average sand collection rate is from 80% to 90% when any one of the configuration parameter levels is changed. However, the variation of a parameter level results in different ef-fects on the sand collection rate for each soil sample within a certain size range of sand grains. The results show that for various sand grain sized soil sample at each wind speed, the sand collection rate decreases when the diameter of the container changes from 50 mm to 40 mm, the sand collection rate increases by about 2%-3% when the inlet width changes from 10 mm to 8 mm, and the sand collection rate increases by about 3%-4% when cone height is altered from 100 mm to 125 mm. The average sand collection rate is enhanced by 2%-4% for the soil sample of different sized sand grains when the diameter of the container is 50 mm, the inlet width is 8 mm, and cone height is 125 mm.  相似文献   
44.
《河南地质》2009,(7):12-13
2008年,我局下发了在全县范围内聘任村级土地协管员的文件,经过乡村及基层国土资源所逐级审查,我们在全县19个乡(镇、办事处)组建了一支由245人组成的村级土地协管员队伍,建立了“局聘所管”的管理体制。经过一年来的任用和管理,这支队伍已经成为我县国土资源系统的重要组成部分。村级土地协管员在政策宣传、协助管理、信息收集等方面的作用得到了充分发挥,目前已经成为国土资源管理部门的好帮手,有力地推动了全县的国土资源管理工作。  相似文献   
45.
在知识爆炸的今天,全面迅速地收集知识信息是人们追求的目标。文章的摘要高度浓缩了全文的知识信息,在信息收集的过程中往往起着关键性的作用,许多收集单位就只收录文章的摘要。所以,写好摘要无疑对知识的传播有着非常重要的意义。  相似文献   
46.
介绍一种碳酸盐中碳、氧同位素快速制样装置。实验证明,该装置具有真空度好、使用方便、无污染、制样效率高、成本低的优点,所生成的二氧化碳具有高纯、分析结果准确、可靠等特点,完全能满足碳酸盐中碳、氧同位素分析的制样要求。  相似文献   
47.
本文介绍了科罗拉多市政公司对地下污水管网系统进行检测评估情况,包括干线、人井、沉淀池等,全面介绍了管网的材质情况、评估进度和费用等。  相似文献   
48.
http://www.sciencedirect.com/science/article/pii/S1674987111000405   总被引:1,自引:0,他引:1  
This study has focused on the processes of soil degradation and chemical element concentration in tea-growing regions of Rwanda, Africa. Soil degradation accelerated by erosion is caused not only by topography but also by human activities. This soil degradation involves both the physical loss and reduction in the amount of topsoil associated with nutrient decline. Soil samples were collected from eleven tropical zones in Rwanda and from variable depth within each collecting site. Of these, Samples from three locations in each zone were analyzed in the laboratory, with the result that the pH of all soil samples is shown to be less than 5 (pH < 5) with a general average of 4.4. The elements such as iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn) are present in high concentration levels. In contrast calcium (Ca) and sodium (Na) are present at low-level concentrations and carbon (C) was found in minimal concentrations. In addition, elements derived from fertilizers, such as nitrogen (N), phosphorous (P), and potassium (K) which is also from minerals such as feldspar, are also present in low-level concentrations. The results indicate that the soil in certain Rwandan tea plantations is acidic and that this level of pH may help explain, in addition to natural factors, the deficiency of some elements such as Ca, Mg, P and N. The use of chemical fertilizers, land use system and the location of fields relative to household plots are also considered to help explain why tea plantation soils are typically degraded.  相似文献   
49.
山西数字地震观测网络项目是山西省地震局承担的中国数字地震观测网络项目的重要组成部分。该项目档案因其完整性、准确性、系统性和安全性于2008年1月顺利通过了中国地震局、国家档案局的检查验收。论述了山西数字地震观测网络项目档案收集和整理工作所取得的成效,并对取得成效的原因进行了分析和总结,从而为今后重大建设项目的档案管理提供借鉴。  相似文献   
50.
本文对我国南极陨石的收集、分类和研究工作进行了回顾和阶段性的总结。4次格罗夫山考察共发现陨石样品9834块,其中已完成和计划2008年完成分类的陨石共2431块。在正式公布的684块已分类陨石中,鉴定出2块火星陨石、2块灶神星陨石、6块橄辉无球粒陨石、5块中铁陨石、1块橄榄陨铁、1块铁陨石以及10块碳质球粒陨石等特殊样品,并对其中的部分样品开展了深入的研究。建议拓展南极陨石的收集,持续开展陨石的分类工作,并提出我国南极陨石研究的重点方向。  相似文献   
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