首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   134篇
  免费   8篇
  国内免费   40篇
安全科学   3篇
废物处理   4篇
环保管理   1篇
综合类   99篇
基础理论   27篇
污染及防治   45篇
评价与监测   2篇
社会与环境   1篇
  2022年   3篇
  2021年   4篇
  2019年   2篇
  2018年   2篇
  2017年   4篇
  2016年   4篇
  2015年   11篇
  2014年   7篇
  2013年   37篇
  2012年   24篇
  2011年   13篇
  2010年   6篇
  2009年   9篇
  2008年   5篇
  2007年   7篇
  2006年   3篇
  2005年   3篇
  2004年   6篇
  2003年   2篇
  2002年   1篇
  2000年   1篇
  1995年   1篇
  1994年   4篇
  1993年   2篇
  1992年   4篇
  1991年   4篇
  1990年   2篇
  1989年   1篇
  1988年   3篇
  1987年   2篇
  1986年   2篇
  1985年   1篇
  1982年   2篇
排序方式: 共有182条查询结果,搜索用时 15 毫秒
151.
采用气相色谱/负离子化学电离质谱法测定地表水中的硫丹及其代谢物,用正己烷提取,外标法定量。α-硫丹、β-硫丹及硫丹硫酸酯在0.200μg/L~10.0μg/L范围内线性良好,方法检出限分别为0.010μg/L、0.008μg/L及0.010μg/L,空白加标平行测定的RSD为3.9%~4.8%,地表水样品加标回收率为85.5%~93.8%。  相似文献   
152.
153.
A simple and robust analytical method was developed to simultaneously detect and quantify 17β-estradiol (E2), estrone (E1), 17β-estradiol-3-sulphate (E2-3S), and estrone-3-sulphate (E1-3S) in aqueous solutions (calcium chloride and artificial urine solutions) and agricultural soils using high performance liquid chromatography and UV detection. The standards for all four compounds were linear in the range of 0.01 to 1.0 μg mL?1 (n = 6) and 1.0 to 20 μg mL?1 (n = 6), respectively, with correlation coefficients > 0.999. The on-column limits of detection at an injection volume of 50 μL and S/N (signal: noise) ratio of 3 were: 9.0 ng mL?1, 10 ng mL?1, 5.0 ng mL?1, and 7.0 ng mL?1 for E2-3S, E1-3S, E2 and E1, respectively. The limit of detection and quantification in artificial urine solution and CaCl2 solution was 1.0 ng mL?1 for all four compounds. Method detection limits for the compounds in the 3 soils ranged from 2 to 2.4 ng g?1 (E2-3S and E1-3S), and 1.0 to 2.9 ng g?1 (E2 and E1), respectively.  相似文献   
154.
聚磷菌胞内多聚物的分析检测方法   总被引:3,自引:0,他引:3  
PHA、糖原和多聚偏磷酸盐这三种多聚物在聚磷茵(PAOs)体内的代谢和生长有着很重要的作用,它们同时也影响污水处理强化生物除磷系统的处理效果,因此需要对胞内聚合物进行分析测定。本文介绍了监测PHA、糖原和多聚偏磷酸盐的常用定量和定性方法,以及部分方法的提取手段、预处理过程、测定原理以及注意事项。  相似文献   
155.
An inter-laboratory comparison exercise was organized among European laboratories, under the aegis of EU COST Action 636: “Xenobiotics in Urban Water Cycle”. The objective was to evaluate the performance of testing laboratories determining “Endocrine Disrupting Compounds” (EDC) in various aqueous matrices. As the main task three steroid estrogens: 17α-ethinylestradiol, 17β-estradiol and estrone were determined in four spiked aqueous matrices: tap water, river water and wastewater treatment plant influent and effluent using GC-MS and LC-MS/MS. Results were compared and discussed according to the analytical techniques applied, the accuracy and reproducibility of the analytical methods and the nature of the sample matrices. Overall, the results obtained in this inter-laboratory exercise reveal a high level of competence among the participating laboratories for the detection of steroid estrogens in water samples indicating that GC-MS as well as LC-MS/MS can equally be employed for the analysis of natural and synthetic hormones.  相似文献   
156.
β-Thalassaemia major patients have chronic anaemia and since 3–4 per cent of Singaporeans carry the β-gene, prenatal diagnosis is essential. We evaluated the amplification refractory mutation system (ARMS) technique as a routine test for prenatal diagnosis of β-major. Six mutations along the β-gene were studied—41–42 (-TCTT), IVSII #654 (C-T), 17β (A-T), – 28 TATA (A-G), IVSI #5 (G-C), and IVSI #1 (G-T). Our results indicate that prenatal diagnosis using these mutations can be offered to 90 per cent (35/39) of our Chinese couples and 54·6 per cent (12/22) of our Malay couples at risk. Confirmation of ARMS results was carried out using allele-specific oligonucleotide hybridization. Prenatal diagnosis using ARMS was successfully carried out in nine cases which included a set of triplets and twins. The triplets were diagnosed with the β-trait carrying the 41–42 mutation. The couple with twins possessed the #654 mutation and one twin was diagnosed with the β-trait and the other with #654 homozygosity. Genomic sequencing of the undefined mutations in the Chinese couples revealed rarer mutations at − 29 and an ATG-AGG base substitution at the initiation codon for translation. In the Malay couples, genomic sequencing detected mutations at codon 15 (TGG-TAG) and codon 26 (GAG-AAG). We conclude that ARMS with its direct detection of amplified products by gel electrophoresis provides an accurate, rapid, and simpler method for our β-thalassaemia prenatal diagnosis programme in Singapore.  相似文献   
157.
This study investigated the electrokinetic (EK) behavior of multiple chlorobenzenes, including 1,2,3,4-tetrachlorobenzene (TeCB), 1,2,4,5-tetrachlorobenzene (i-TeCB), and 1,2,3-trichlorobenzene (TCB) in contaminated clayed soils. The effect of β-cyclodextrin (β-CD) on the EK removal of the chlorobenzenes was studied. The largest removal was obtained when Na2CO3/NaHCO3 buffer was used as anodic purging solution without β-CD. The removal efficiencies were related to the aqueous solubilities of chlorobenzenes. With the same cumulative electroosmotic flow, greater solubility led to higher removal efficiency. The addition of β-CD inhibited the EK removal efficiency of all chlorobenzenes. The inhibition increased with the increase of β-CD concentration. With the same β-CD concentration, the inhibition increased with the rise of electric potential. It was found that the inclusion compounds between β-CD and chlorobenzenzes were less soluble than chlorobenzenes. The formation of the less soluble inclusion compounds reduced the aqueous solubility of chlorobenzenes and led to the partial immobilization of the chlorobenzenes that desorbed from soil. It was feasible to use the EK technology to remove chlorobenzenes in contaminated soils using water as the anodic flushing solution. The addition of β-CD was not recommended for the EK removal of chlorobenzenes.  相似文献   
158.
Amniotic fluid levels of pregnancy-specific β1-glycoprotein (SP1) were elevated in four pregnancies with Meckel's syndrome at 16 and 26 weeks, and the levels of hCG were also elevated in three out of four cases. These findings suggest a potential new application of SP1 measurement for prenatal diagnosis.  相似文献   
159.
This study describes three couples a t risk for homozygous β-thalassaemia in which one of the partners carried a short deletion β-thalassaemia defect. Detection of short deletions in trophoblast DNA was accomplished by the very simple procedure of non-denaturing polyacrylamide gel electrophoresis. This method may be applied to detect β-thalassaemia mutations due to deletion or addition of more than two nucleotides.  相似文献   
160.
多氯联苯对孔雀鱼卵黄蛋白原的诱导及检测   总被引:3,自引:0,他引:3  
为探讨利用孔雀鱼(Poecilia reticulata)卵黄蛋白原(Vitellogenin,Vtg)作为生物标志物检测环境雌激素的可行性,采用浸浴法分别使用17β-雌二醇(E2)和多氯联苯(PCBs)对雄性孔雀鱼成鱼进行染毒,30d后测定其性腺系数(GSI)和肝指数(LSI),并将鱼体整体匀浆进行常规聚丙烯酰胺凝胶电泳(Native-PAGE)及磷、脂和糖蛋白特异染色分析.结果表明,PCBs对雄性孔雀鱼具有雌激素效应,和E2均可以诱导雄性孔雀鱼体内产生Vtg,但诱导组雄鱼GSI及LSI与对照组比较均无显著性差异(p>0.05).Native-PAGE及磷、脂、糖蛋白特异性分析表明,孔雀鱼Vtg是一种富含磷、脂、糖的蛋白,具有VtgⅠ、VtgⅡ和VtgⅢ等3种形式,其分子量分别为642kDa、541kDa和441kDa.雄性孔雀鱼Vtg可作为环境雌激素监测的有效生物标记物.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号