全文获取类型
收费全文 | 74篇 |
免费 | 5篇 |
国内免费 | 20篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 1篇 |
环保管理 | 7篇 |
综合类 | 59篇 |
基础理论 | 3篇 |
污染及防治 | 6篇 |
评价与监测 | 19篇 |
社会与环境 | 1篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 6篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 5篇 |
2008年 | 3篇 |
2007年 | 6篇 |
2006年 | 10篇 |
2005年 | 3篇 |
2004年 | 5篇 |
2003年 | 3篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1992年 | 2篇 |
1977年 | 1篇 |
排序方式: 共有99条查询结果,搜索用时 15 毫秒
41.
水中阴离子表面活性剂的偶氮红滴定法测定 总被引:1,自引:0,他引:1
采用偶氮红两相滴定法测定水中阴离子表面活性剂,有效地消除了环境水体中硬度、蛋白质、淀粉及非离子表面活性剂的干扰。其平均回收率为100.6%,相对标准偏差为1.0%。 相似文献
42.
43.
44.
水溶液中二氧化氯及系列氧化物的测定 总被引:7,自引:0,他引:7
根据碘离子在不同pH值与ClO2、Cl2、ClO2-、ClO3-发生不同反应的原理,提出同时分析含氯系列氧化物的方法.相对标准偏差1.2%~6.5%,加标回收率可达92.6%~94.8%.该方法不仅可用于测定二氧化氯发生器产物各组分的浓度,还能用于测定给水和废水处理中的二氧化氯. 相似文献
45.
The metal ion binding characteristics of particulate matter obtained from column experiments on the anaerobic digestion of solid waste were studied using a titrimetric approach. The experimental set-up allowed us to study the dynamics of particle bound ligand concentrations during digestion processes typically found in landfills.We developed a continuous titration method by simultaneously using a Cd-sensitive and pH electrode and combining metal and acid/base titrations. This technique allows for a more precise determination of pKa-log KM pairs for each ligand than metal titrations alone. The results were compared with titration methods using differential pulse anodic stripping voltammetry (DPASV) and atomic absorption spectroscopy (AAS) with longer equilibration times in order to further characterize ligand properties such as reaction kinetics, the electrochemical lability of the respective complex during DPASV, the distinction between metal adsorption to particulate matter and metal complexation by soluble ligands adhered to particles, reversibility of the binding process by competition studies, and resistance against purging with nitrogen gas.The properties of seven major metal binding ligands were identified and assignments to the most likely functional groups were made. The most important ligand properties are for ligand A: pKa ≈ 9.2, log Kcd ≈ 7.0 fast reaction kinetics (mercapto groups); ligand B: pKa = 4.8, log KCd ≈ 6.0, slow reaction kinetics (chelates with 3 or 4 carboxylic groups); ligand C: pKa ≈ 6.0, log KCd ≈ 13.0, irreversible metal binding at basic pH-values (uptake inside bacterial cells); ligand D: pKa = 7.7, log KCd = 4.0, runs parallel to N content of particulate matter with digestion time (primary amines neighboring oxo groups); ligand E: pKa ≈ 12.0, log KCd = 9.0, runs parallel to P content of particulate matter (phosphate); ligand F:pKa > 9.0, log KCdf = pKa + 0.4, runs parallel to N content of particulate matter (primary amines neighboring SH groups); and ligand G: pKa ≤ 4.8, log KPb ≈ 4.3, strong Pb2+ ligand, even at low pH-values.Metal ions were found to be irreversibly bound by ligand C at low heavy-metal concentratins, whereas at higher concentrations the binding is reversible and can be predicted using the mass of the digestion process (methanogenic phase). All other ligands have their concentration maximum in the transition phase between acetogenic and methanogenic phase. 相似文献
46.
47.
Metachromatic polyelectrolyte titration was investigated as a means of analyzing polymeric quaternary ammonium salts (polyquaterniums) of relatively low charge density used as ingredients in cosmetics. They are of possible toxicological concern, but little is known of their environmental fate and behavior. With o-toluidine blue as the indicator, determination of the concentration of a range of polyquaterniums of commercial importance and cosmetic origin was possible. Using a visual endpoint, normalities as low as 3 × 10?5 N could be determined, while with a spectrophotometric endpoint, the technique was effective to approximately 3 × 10?6 N. The concentrations (g L?1) to which these normalities correspond depend on the charge density of the polymer. Polyquaterniums are frequently used in association with anionic surfactants in cosmetic formulations and the presence of an anionic surfactant even in excess did not affect results although the color change was less stable. Titration in the presence of prepared humic acid was also possible. 相似文献
48.
重金属离子与典型离子型有机污染物的络合效应研究 总被引:2,自引:0,他引:2
采用自动电位滴定法,研究了水环境中4种常见的重金属离子Cu2+、Pb2+、Zn2+、Cd2+与环丙沙星、磺胺甲基嘧啶和全氟辛酸的络合效应.测定了3种有机物与4种金属离子的络合常数logK值,计算了各种络合物在不同pH值下的形态分布. 结果表明,Cu2+与环丙沙星能形成较为稳定的络合物Cu(cip±)2+、Cu(cip±)22+、Cu(cip-·cip±)+,其络合能力要远强于Pb2+、Zn2+、Cd2+,前者形成的络合常数要比后三者高出3个数量级.4种金属离子与磺胺甲基嘧啶均有一定的络合能力,但稳定常数差别不大.全氟辛酸分子中由于带有较多的电负性强的F,表现出强酸的性质,与4种金属离子未见明显的络合作用. 相似文献
49.
水的总硬度测定采用EDTA进行络合滴定。实验中用自动电位滴定仪代替人工进行样品分析,由颜色突变判断滴定终点改为电位突变,具有高硬度样品预判断、滴定干扰小、准确度高、节省人力、便于数据记录统计比较等优点。 相似文献
50.
以三氧化钨为催化剂,燃烧处理植物叶片,硫转化为SO2,后者被吸收液吸收后采用库仑滴定法测定。方法快速简便,测定植物叶片中硫的含量,相对标准偏差为1.5%,适用于大批量样品的快速测定。 相似文献