太湖水污染扩散插件式模拟系统     

韩宇  郭飞  葛成  张凤 《地球信息科学学报》2011,13(2):245-251

插件式太湖水污染扩散模拟系统,基于三维水体污染扩散模型,结合GIS技术和三维可视化技术,再现了水体污染物运移扩散的时空分布特征与动态演进过程.为了保证系统的可扩展性,需要一种松散的耦合机制.插件技术可以有效地降低系统功能模块间的耦合,把插件技术引入GIS的二次开发可以赋予系统动态可扩展性.本文首先,介绍插件式系统的一般...  相似文献   

Effects of heavy metal ions (Cu2+, Pb2+ and Cd2+) on DNA damage of the gills, hemocytes and hepatopancreas of marine crab, Charybdis japonica     

Luqing Pan  Na Liu  Hongxia Zhang  Jing Wang  Jingjing Miao 《中国海洋大学学报(英文版)》2011,10(2):177-184

There are rising concerns about the hazardous effects of heavy metals on the environment. In this study, comet assay and DNA alkaline unwinding assay were conducted on the tissues (gills, hepatopancreas, and hemocytes) of Charybdis japonica in order to illustrate genotoxicity of three heavy metal ions (Cu2+, Pb2+, and Cd2+) on the marine crabs C. japonica. The crabs were exposed to Cu2+ (10, 50, and 100 ?g.L?1), Pb2+ (50, 250, and 500 ?g L?1) and Cd2+ (5, 25, and 50 ?g L?1), and the tissues were sampled at days 0.5, 1, 3, 6, 9, and 15. DNA alkaline unwinding assay was used for testing the DNA single strand break in gills and hepatopancreas and comet assay was employed for testing the DNA damage in hemocytes. The results showed that the DNA damage (F-value) of gills in the crabs exposed to the three heavy metals was decreased gradually during the exposure periods and there was a dose-time response relationship in certain time, suggesting that the levels of DNA single strand break in all the experimental groups increased significantly compared to the controls. Changes of F-value in hepatopancreas of the crabs exposed to the three heavy metals were similar to those in gills except that the peak values were found in the 500 ?g L?1 Pb2+ treatment group at day 3 and the 50 ?g L?1 Cd2+ treatment group at day 9. The ranks of DNA damage in gills and hepatopancreas induced by the three heavy metal ions (50 ?g L?1, day 15) were Cd2+ >Pb2+ >Cu2+ and Pb2+ >Cu2+ >Cd2+. The levels of DNA damage in gills were higher than those in hepatopancreas in the same experimental group. It can be concluded that indices of DNA damage can be used as the potential biomarkers of heavy metal pollution in marine environment.  相似文献   

防风化喷涂技术在鲁村煤矿回风暗斜井的应用          下载免费PDF全文

文增生  史春芝  单吉成 《山东国土资源》2011,27(9):45-47

基于煤巷锚网支护巷道受矿井潮湿环境影响出现的金属网锈蚀断裂、煤壁片帮、巷道失修等实际情况,使用方案比较的方法,分析了喷射混凝土封闭工艺和灰浆喷涂工艺优缺点,进而确定采用防风化喷涂技术进行施工。经实际应用,防风化喷涂技术对鲁村煤矿回风暗斜井的煤壁等四周围岩和锚杆、金属网起到了良好的封闭和防风化效果。保证了巷道正常的回风、行人需要,延长了巷道的服务期限。  相似文献   

Servicing a world elsewhere? Examining everyday work practices in the emerging economic spaces of Malaysia's business process outsourcing industry     

Daniel Brooker 《Singapore journal of tropical geography》2011,32(2):141-154

The paper seeks to illuminate everyday work practices in the economic spaces of Malaysia's business process outsourcing (BPO) industry. It draws upon empirical evidence from call centre staff and promotes analytical sensitivity to the experience of labour and spatiotemporal relations within the offshore back offices of multinational corporations located in Cyberjaya, Malaysia. The analysis provides an empirical snapshot of how IT‐facilitated work practices in the global information economy are embedded and socially reproduced in everyday settings. To this end, the paper engages anthropologically with BPO labour, and critiques ‘globalist’ representations of economic and social transformation frequently articulated through an abstract, dehumanized space of networks and flows often seen to wash over local places, culture and people.  相似文献   

中国制造业FDI技术溢出效应——基于苏粤数据的实证与比较分析     

张希  陈甜蜜 《地域研究与开发》2011,30(6):6-11,32

选取2000—2009年江苏省和广东省为样本,考虑到技术溢出可能存在非线性和滞后性,构建引入了溢出变量的二次项和滞后一期的工业增加值面板数据模型,实证考察了外商直接投资在苏粤两省制造业各子行业产生的技术溢出效应。分析结果表明:江苏省FDI存在显著的行业内和后向技术溢出效应,广东省存在显著的行业内和行业间技术溢出效应。进一步通过对两省实证结果的对比,得出结论并提出政策建议。  相似文献   

煤田地质超深孔钻探工艺     

孙贵生  张纯峰 《中国煤炭地质》2015,(1):57-61

在对深部煤田地质钻孔钻进工艺研究的基础上,有针对性选择使用聚合物泥浆,解决了基浆配制用水及泥浆抗地表水水质污染问题。通过改变双管钻具长度和改换取心钻头的切削具,满足软硬互层对钻头钻进效率的影响。在煤系地层钻进中,除采用常规的单管钻具钻进外,在见煤预告下过后,采用加长双管取心钻具,既可保证了回次进尺,又可保证岩心的采取。多项措施落实,不仅解决了生产中的一些难题,收到了较好的效果,而且创造了河北省煤田地质局煤田地质单孔钻探深度2 009.12m的新纪录,为今后深部钻孔的施工积累了经验。  相似文献   

卵石地层的特殊性及其对基坑支护的影响分析     

刘伍  李海明 《城市地质》2015,(Z2)

主要从卵石地层的特征分类、特殊结构及场内施工条件3个方面,对基坑支护结构选型及施工工艺选择进行深入、系统的分析论证,力求使在卵石地层中的基坑支护设计方案更科学、经济,使施工方法、工艺更具可操作性。  相似文献   

苏77-5-8H井大斜度穿煤层安全钻井技术          下载免费PDF全文

柯学  李继营  池崇荣  刘志良 《探矿工程》2011,38(12):13-17

苏77-5-8H井为苏里格气田苏77区块第一口利用水平井提高山23组开发效益的大斜度穿煤层水平井,目的层山23储集砂岩上部发育厚度25～30 m的碳质泥岩和煤层段,由于煤系地层的特殊性,钻进过程中易坍塌,且煤系地层正好处于入靶前的造斜井段,钻井施工难度大、风险高。在分析了煤层井壁稳定机理基础上,针对苏77区块地层特性和水平井钻井施工的难点,分析了该井主要技术难点,重点从井眼轨迹轨道设计优化、轨迹控制及施工技术措施和钻井液技术等方面对该井安全技术进行了全面的介绍,为今后同类井钻井提供可参考的经验。  相似文献   

松辽地区油气勘探优快钻井技术思路          下载免费PDF全文

任杭洲  李翔 《探矿工程》2011,38(10):15-18

吉林松辽地区的腰英台、秦家屯十屋、八屋区块以及梨树断陷、长岭断陷的外围中深探井和伏龙泉浅层气井是中石化东北地区的重点区块。自勘探开发以来钻井提速面临重重困难,2010年是中原油田钻井队伍进入该市场以来的提速年,以提速为目标,大胆创新,通过大量的邻井调研分析,针对不同井的特点分别制定了不同的钻井提速措施。在成熟的钻井模式下通过不断地、连续地优化钻头选型,强化钻井参数,推广大功率高温螺杆复合钻进技术,细致的单井钻井方案优选,挖掘提速潜力,创出了有史以来最好的钻探成绩。详细介绍了松辽地区油气勘探优快钻井技术方案及具体措施。  相似文献   

渭北煤田澄合矿区复杂地层钻孔施工技术   总被引：2，自引：0，他引：2       下载免费PDF全文

黄建宁  刘文革 《探矿工程》2011,38(6):22-25

渭北煤田澄合矿区属典型复杂地层,钻探施工难度大,钻探效率低。通过对钻探施工中的难点进行分析,总结了本地区钻探施工技术经验,针对钻探施工中存在的厚黄土层钻进、钻孔漏失和坍塌、岩石坚硬、粉煤采取等问题,提出了应对的技术措施和钻进施工工艺。  相似文献