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641.
Atmospheric samples have been collected in Strasbourg between April 18 and May 29, 2007 and were analyzed for 71 current-use pesticides, of which 38 were detected. Average concentrations ranged from 0.09 ng m−3 for Fenarimol to 110.42 ng  m−3 for Dimethachlor, which was slightly higher than the concentrations reported from other, comparable agricultural regions.Significant temporal variations were observed for 30 pesticides, and for most of them it could be shown that these were linked to time, temperature or atmospheric pressure. In several cases this helped to identify pesticide application just before or at the beginning of the sampling period, or ongoing treatment. Humidity, in contrast to previous reports, could not be linked to these variations. For the other 8 pesticides, only very little temporal variations were observed. Generally, these concentrations were low (less than 1 ng m−3), and it was assumed that they are not in use in Alsace at present.  相似文献   
642.
陈翠萍  牛怀文 《四川环境》2009,28(4):136-140
本文以仪征市现有耕地土壤为调查对象,通过布点、采样、检测、统计,结果表明,仪征市沿江圩区长江冲积母质发育的土壤比丘陵地区下蜀黄土重金属含量相对较高,土壤重金属含量多年来有升高现象,少数田块存在高残农药的残留,点源污染和农药污染对耕地环境质量的影响不容忽视,需要采取工程、生物和化学等技术对土壤进行修复。  相似文献   
643.
Accident investigation manuals are influential documents on various levels in a safety management system, and it is therefore important to appraise them in the light of what we currently know – or assume – about the nature of accidents. Investigation manuals necessarily embody or represent an accident model, i.e., a set of assumptions about how accidents happen and what the important factors are. In this paper we examine three aspects of accident investigation as described in a number of investigation manuals. Firstly, we focus on accident models and in particular the assumptions about how different factors interact to cause – or prevent – accidents, i.e., the accident “mechanisms”. Secondly, we focus on the scope in the sense of the factors (or factor domains) that are considered in the models – for instance (hu)man, technology, and organization (MTO). Thirdly, we focus on the system of investigation or the activities that together constitute an accident investigation project/process. We found that the manuals all used complex linear models. The factors considered were in general (hu)man, technology, organization, and information. The causes found during an investigation reflect the assumptions of the accident model, following the ‘What-You-Look-For-Is-What-You-Find’ or WYLFIWYF principle. The identified causes typically became specific problems to be fixed during an implementation of solutions. This follows what can be called ‘What-You-Find-Is-What-You-Fix’ or WYFIWYF principle.  相似文献   
644.
事故调查分析方法与技术述评   总被引:1,自引:0,他引:1  
根据事故的原因结果模型、过程模型、能量模型、逻辑树模型、SHE管理模型将事故调查分析技术方法归纳为5大类,介绍了广泛使用的事故调查分析技术方法的特点,并按一定的标准进行分析和比较。分析表明:每种方法都有其不同的应用领域和优缺点,应针对不同领域问题选用合适的分析方法,多种调查技术组合分析适用于复杂事故的调查;考虑事件次序及其影响因素的调查方法,便于提出预防事故再次发生和减少风险的建议,图表阐述有利于鉴别信息缺陷,并使调查组之间的沟通有力;笔者在调查过程中注重于非正常分析方法得出的结果,宜采用更为先进的事故分析技术方法以保证事故调查的客观性。  相似文献   
645.
Facile, selective and sensitive spectrophotometric method has been developed for the determination of carbosulfan in insecticidal formulations, fortified water, food grains, agriculture wastewater and soil samples with newly synthesized reagents. The method was based on acid and alkaline hydrolysis of the carbosulfan pesticide, and the resultant hydrolysis product of carbosulfan was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with λ max of 464 nm or interaction with 2,6-dibromo-4-nitroaniline to produce yellow colored product with λ max of 408 nm or coupling with 2,4,6-tribromoaniline to form red colored product has a λ max of 471 nm. Under optimal conditions, Beer’s law range for 2,6-dibromo-4-methylaniline (DBMA) was found to be 0.2–12.0 μg ml−1, 0.6–16.0 μg ml−1 for 2,6-dibromo-4-nitroaniline (DBNA) and 0.4–15.0 μg ml−1 for 2,4,6-tribromoaniline (TBA). The molar absorptivity of the color systems were found to be 3.112 × 104 l mol−1 cm−1 for DBMA, 3.214 × 104 l mol−1 cm−1 for DBNA and 3.881 × 104 l mol−1 cm−1 for TBA. Sandell’s of the color reactions are 0.013 μg cm−2 (DBMA), 0.012 μg cm−2 (DBNA) and 0.011 μg cm−2 (TBA) respectively. The effect of the non-target species on the determination of carbosulfan was studied to enhance the selectivity of the proposed methods. The formation of colored derivatives with the coupling agents is instantaneous and stable for 28, 30, and 26 h. Performance of the proposed methods were compared statistically in terms Student’s F and t-tests with the reported methods. An erratum to this article can be found at  相似文献   
646.
摘要:制备了一种新型的纳米TiO2-碳纳米管复合膜修饰电极,在pH值为5.57的NaAc-HAc缓冲溶液中,研究了α-萘酚和β-萘酚在该修饰电极上的电化学行为,据此建立了纳米TiO2-碳纳米管复合膜修饰电极伏安法测定水中α-萘酚和β-萘酚的方法。优化了试验条件,α-萘酚和β-萘酚分别在8.3×10^-7mol/L—1.0×10^-5mol/L和7.8×10^-7mol/L—1.0×10^-5mol/L范围内,浓度与氧化峰电流呈良好的线性关系,开路富集3min,检出限分别为3.5××10^-7mol/L和2.3×10^-7mol/L,模拟水样测定的回收率为97.6%—101%。  相似文献   
647.
用标准菌株对比了酶底物法和多管发酵法及快速纸片法,监测分析了分组环境水样中的大肠菌群。结果表明,酶底物法操作快速、简单、结果稳定、无二次污染,能满足水质监测和应急监测的需求。  相似文献   
648.
毛细管柱气相色谱法测定水中痕量拟除虫菊酯杀虫剂   总被引:11,自引:1,他引:10  
采用石油醚萃取水样 ,萃取液经氮气吹扫浓缩后 ,用气相色谱仪对水样中拟除虫菊酯杀虫剂——甲氰菊酯、三氟氯氰菊酯 (功夫 )、高效氯氰菊酯、氰戊菊酯、溴氰菊酯进行了定量测定。由于毛细管柱的高柱效和微池 ECD的高灵敏度 ,使得上述目标组分与水样中的其它杂质能达到较好的分离 ,即使含量极低也能被检出。本方法省去了样品萃取液的净化处理这一步骤 ,可较快地测定拟除虫菊酯杀虫剂 ,在污染事故应急监测方面具有实用性。  相似文献   
649.
同步荧光光谱法测定环境水样中的多环芳烃   总被引:1,自引:0,他引:1  
为了建立快速测定水体中多环芳烃的方法,用恒波长同步荧光法对14种多环芳烃混合标样进行了分析。在优化的实验条件下,对环境水样进行分析,可以鉴别出11种多环芳烃。14种PAHs在0~1000ng/ml范围内呈良好的线性关系,相关系数r均不小于0.9988,相对标准偏差(RSD)在1.06%~1.67%之间(n=6)。14种PAHs的检出限在0.072~3.9ng/ml之间。该方法应用于污水、样河水样、池塘水样中的多环芳烃检测取得了良好的效果,回收率分别为82.2%~111.0%、86.0%~107.0%、88.0%~106.2%(n=5)。  相似文献   
650.
应用电感耦合等离子体质谱法对水样(地表水、饮用水等)中铜、锌、硒、砷、镉、铬、铅、铁、锰等痕量元素进行分析测定。结果表明,方法检出限为0.01~0.78μg/L,平行测定的相对标准偏差为0.6%~7.9%,实际水样加标回收率为90.5%~103%。该方法快速、简便、线性范围大,具有良好的检出限和准确度。  相似文献   
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