深水钻井隔水管磁记忆内检测装置研发及应用

为了解决深水钻井隔水管裂纹、磨损、疲劳损伤等检测难题,基于磁记忆检测技术研制1种内检测器.其主要结构包括:数据采集腔,周向布置的60路GMR高灵敏度传感器,导向支撑轮,吊装牵拉钩等.该设备可以在不拆卸浮力块的情况下完成隔水管内壁的覆盖式扫查.结果表明:检测器具备较高的可靠性,操作简单、检测效率高;检测数据可以有效反映隔...     

饮用水消毒副产物-卤乙酸的分析检测

卤乙酸是氯化消毒饮用水中一类主要的消毒副产物 ,由于存在的广泛性和潜在的健康危害 ,许多国家和卫生组织相继将其列为饮用水常规监测项目 ,而我国至今还没有相关规定 ;为更好地控制饮用水中卤乙酸的形成 ,世界各国科研人员先后研究和开发出了性能逐趋完善的多种分析检测方法 ;在大量国内外文献调研的基础上 ,对卤乙酸的各种分析检测方法进行系统的介绍 ,并指明今后的发展方向     

低浓度SO_2检测管的研制

通过对常见的几种检测管法的比较，筛选出灵敏度较高的亚硝基铁氰化钠法；同时筛选出载体为６０—８０目的素陶瓷，指示剂浓度为２０％。玻璃管内径为２．０—２．３ｍｍ，采气速度为０．３（Ｌ／ｍｉｎ），采样体积为１２Ｌ，以此条件进行实验．结果表明，检测管变色长度对应ＳＯ２浓度的相关性很好；变异系数均小于１１０％，检测的重现性较好。检测管的测定值与理论值的平均相对误差为５．０９％（＜±１５％），最大相对误差为７．１３％（＜±２５％），准确度较高．测定结果可靠；与化学法比较，两者无显著性差异；浓度小于０．１５ｍｇ／ｍ３的Ｈ２Ｓ及浓度小于０．０１ｍｇ／ｍ３的ＮＯ２对ＳＯ２检测管无干扰．     

光声火灾探测系统新模型

普通光声气体探测模型因其实时性能差及波段要求高而不适用于火灾报警系统。本文介绍一种基于光声原理的CO在线测量的火灾报警模型。光声腔中采用纯CO气体代替气体采样,通过红外光源与光声腔之间的吸收路径测量火灾气体。一旦火灾气体经过该路径,将在不同吸收线上导致到达光声腔辐射量的减小。因此,只有与光声腔中气体一致的成分才能减弱初始光声信号,而信号变化代表了CO的存在。     

CdSe量子点的合成及其在重金属离子检测中的应用

以3-巯基丙酸（3-MPA）为修饰剂合成了水溶性CdSe量子点,优化了合成条件,并以其为荧光探针建立了水样中Pb²⁺和Hg²⁺的检测方法。实验结果表明：在n（Se）∶n（Cd²⁺）为1∶6、n（Se）∶n（NaBH₄）为1∶3、n（Cd²⁺）∶n（3-MPA）为1∶6、反应pH为11、回流温度为100 ℃、回流时间为60 min的优化条件下合成的量子点荧光性能较优;量子点的荧光猝灭强度与Pb²⁺或Hg²⁺的质量浓度呈良好的线性关系,线性范围分别为0.005~10 mg/L和0.001~1 mg/L,检出限分别为0.003 mg/L和0.001 mg/L,相对标准偏差分别为1.23%和1.29%,可应用于实际水样中Pb²⁺和Hg²⁺的检测。     

Forest Dynamics in the Eastern Ghats of Tamil Nadu,India

The primary deciduous forests in the Eastern Ghats (EG) of Tamil Nadu (TN) India have undergone many changes owing to various need-based forest managements, such as timber extraction for industry, railway sleepers, charcoal, and forest clearance for hydroelectric projects and agriculture, during preindependence and postindependence periods (i.e., from 1800 to 1980). The enactment of a forest conservation act during the 1980s changed the perception of forest managers from utilization to conservation. This study was taken up to assess the forests dynamics in the EG of TN spatially between 1990 and 2003 and nonspatially between 1900 and the 1980s. Landsat Thematic Mapper (TM) and Indian Remote Sensing satellite (IRS) 1D Linear Imaging and Self Scanning (LISS III) data were used to assess forests during 1990 and 2003, respectively. Field floristic survey and secondary data (such as published literature, floras, books, and forest working plans) were used to assess the forest dynamics in terms of forest type and species composition among the preindependence period, the postindependence period, and the present (i.e., before and after 1980). The satellite data analysis revealed a considerable amount of changes in all forest types during the 13 years. The comparison of species composition and forest types between the past and present revealed that need-based forest management along with anthropogenic activity have altered the primary deciduous forest in to secondary and postextraction secondary forests such as southern thorn and southern thorn scrub forests in the middle [400–900 m above mean sea level (MSL)] and lower slopes (<400 m MSL). However, the evergreen forests present at the upper slope (>900 m MSL) and plateau seemed not to be much affected by the forest management. The changes estimated by the satellite data processing in the major forest types such as evergreen, deciduous, southern thorn, and southern thorn scrub are really alarming because these changes have occurred after the implementation of a forest conservation act. The dependence of local people on forests for various purposes in this region is also considerably high, which might be a key factor for the changes in the forests. The results of this study not only provide an outlook on the present status of the forests and the change trends but also provide the basis for further studies on forests in the EG of TN.     

西南地区高校冬季室内二氧化碳浓度的测试研究

以西南科技大学为研究对象,用便携式红外线二氧化碳分析仪对其冬季室内CO2浓度进行测试分析,测试大学教室课前课后及寝室有人状态下CO2的浓度,包括普查检测以及连续监测。普查检测结果显示20％的样本CO2超过国家规定的上限值（0．10％）,且超标的样本在检测时都处于通风状态不佳时;连续监测则反映出室内CO2的增长与室内人数、房间体积以及通风情况的关系,建议尽量减小室内人员密度,增强通风,以此来确保高校师生身体健康。     

地震的生态破坏及其恢复重建研究进展

本文从地震对生态系统的主要影响、地震破坏的生态系统恢复重建的政策及技术措施等方面,系统分析了目前国内外在地震灾害对生态系统危害方面的研究进展,以及治理中采取的政策和技术措施。在此基础上,提出了震后生态恢复重建的策略和建议,以及今后对震后生态系统快速重建和生态系统服务功能恢复中需要加强的基础研究工作。