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421.
吹扫捕集与气相色谱-质谱联用测定饮用水和地表水中挥发性有机污染物 总被引:36,自引:1,他引:35
报道了Trap I(VOCARB 4000)柱捕集水中挥发性有机污染物的性能和条件,建立了吹扫捕集和气相色谱-质谱联用测定饮用水和地表水样中25种挥发性有机污染物的分析方法.水样的加标回收率在90%~110%之间,最低检测限在0.04~0.85μg/L之间,20μg/L的挥发性有机物标准溶液经重复6次测定,其相对标准偏差基本小于5.0%.该方法已成功地运用于饮用水和地表水中挥发性有机污染物的测定,结果令人满意. 相似文献
422.
梳理了高校实验室环境-安全-健康准入制度包含的管理内容,从人员管理、设备管理、试剂管理、实验环境管理角度进行了分析。根据现有实验室安全信息化系统运行情况,探讨了将实验室安全信息化系统与实验室信息化系统、设备管理信息化系统进行数据融合和功能优化的要点,重点分析了设备采购及管理系统、实验室安全教育与考试系统、实验室安全检查系统、试剂管理平台、实验室门禁管理系统在功能上的内在关联,从而通过试剂管理平台、实验室门禁控制系统、设备采购系统实现实验室环境-安全-健康准入制度的强制执行。研究发现,高校与环境监测实验室、院系实验室安全管理部门联合促进实验室安全信息化系统、实验室信息化系统、设备管理信息化系统的数据共享与功能升级,可以丰富实验室安全准入制度的内涵和管理手段,加强实验室安全准入制度的强制执行力,提高实验室安全管理效率。 相似文献
423.
424.
膜、柱串联固相萃取-高效液相色谱法测定水中多环芳烃(PAHs)的研究 总被引:6,自引:1,他引:5
建立了用膜-柱串联固相萃取(SPE)技术,甲醇和水作为流动相进行梯度洗脱,紫外和荧光检测器串联的高效液相色谱法(HPLC)分析水中EPA优先监控的16种PAHs的方法. 相似文献
425.
介绍了多级活性生化处理 (MSABP)这项新的废水处理技术的原理、技术特点及两个实例运用。这是此项技术在国内的首次运用 ,其最大的优点是无剩余污泥产生 ,不需要沉淀池 相似文献
426.
427.
水质监测中未确知信息的数学处理 总被引:3,自引:0,他引:3
介绍了未确知信息的重要意义 ,并通过实例说明了未确知信息的数学处理方法和过程。应用于水质监测数据处理的结果表明 ,其评价结果符合实际。文末给出了分析结果并针对结果进行了讨论 相似文献
428.
Nowadays, intensive breeding of poultry and livestock of large scale has made the treatment of its waste and wastewater an urgent
environmental issue, which motivated this study. A wetland of 688 m2 was constructed on an egg duck farm, and water hyacinth
(Eichhornia crassipes) was chosen as an aquatic plant for the wetland and used as food for duck production. The objectives of this
study were to test the role of water hyacinth in purifying nutrient-rich wastewater and its effects on the ducks’ feed intake, egg laying
performance and egg quality. This paper shows that the constructed wetland removed as much as 64.44% of chemical oxygen demand
(COD), 21.78% of total nitrogen (TN) and 23.02% of total phosphorus (TP). Both dissolved oxygen (DO) and the transparency of the
wastewater were remarkably improved, with its transparency 2.5 times higher than that of the untreated wastewater. After the ducks
were fed with water hyacinth, the average daily feed intake and the egg-laying ratio in the test group were 5.86% and 9.79% higher,
respectively, than in the control group; the di erences were both significant at the 0.01 probability level. The egg weight in the test group
was 2.36% higher than in the control group (P < 0.05), but the feed conversion ratios were almost the same. The eggshell thickness
and strength were among the egg qualities significantly increased in ducks fed with water hyacinth.We concluded that a water hyacinth
system was e ective for purifying wastewater from an intensive duck farm during the water hyacinth growing season, as harvested
water hyacinth had an excellent performance as duck feed. We also discussed the limitations of the experiment. 相似文献
429.
CHEN Jian XIE Huijun ZHUANG Xuliang ZHUANG Guoqiang BAI Zhihui ZHANG Hongxun 《环境科学学报(英文版)》2008,20(6):725-731
The addition of simple substrates could affect the microbial respiration in soils. This substrate-induced respiration is widely used to estimate the soil microbial biomass, but little attention has been paid to its influence on the changes of community-level physiological profiles. In this study, the process of microbial communities responding to the added substrate using sole-carbon-source utilization (BIOLOG) was investigated. BIOLOG is biased toward fast-growing bacteria; this advantage was taken to detect the prompt response of the active microbial communities to the added substrate. Four soil samples from agricultural fields adjacent to heavy metal mines were amended with L-arginine, citric acid, or D-glucose. Substrate amendments could, generally, not only increase the metabolic activity of the microbial communities, but also change the metabolic diverse patterns compared with no-substrate control. By tracking the process, it was found that the variance between substrate-induced treatment and control fluctuated greatly during the incubation course, and the influences of these three substrates were different. In addition, the application of these induced changes to discriminate soil microbial communities was tested. The distance among all samples was greatly increased, which further showed the functional variance among microbial communities in soils. This can be very useful in the discrimination of microbial communities even with high similarity. 相似文献
430.
闽江河口湿地土壤对痕量元素吸附-解吸特征及其对pH值变化的响应 总被引:1,自引:0,他引:1
选择闽江河口鳝鱼滩的芦苇湿地、短叶茳芏湿地及二者交错带湿地为对象,研究了湿地土壤痕量元素的吸附-解吸特征及其对pH值变化的响应.结果表明,3种湿地土壤对Cr6+、Ni2+和Cd2+的吸附能力及其对Cr6+和Ni2+的最大缓冲容量均表现为短叶茳芏湿地低于交错带湿地和芦苇湿地;对Cu2+和Zn2+的吸附能力和最大缓冲容量在0~30 cm土层均以芦苇湿地较高,而在30~60 cm土层以短叶茳芏湿地较高.导致3种湿地土壤对痕量元素吸附能力差异的原因主要与土壤颗粒组成和pH值的差异有关.Langmuir吸附等温方程可较好地拟合湿地土壤吸附Cr6+、Ni2+、Cu2+、Zn2+和Cd2+的热力学过程(R2≥0.82).3种湿地土壤中Cr6+、Ni2+、Cu2+ 相似文献