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   829篇
  免费   30篇
  国内免费   163篇
安全科学   11篇
废物处理   10篇
环保管理   41篇
综合类   336篇
基础理论   141篇
污染及防治   216篇
评价与监测   264篇
社会与环境   3篇
  2024年   2篇
  2023年   7篇
  2022年   18篇
  2021年   15篇
  2020年   14篇
  2019年   23篇
  2018年   16篇
  2017年   24篇
  2016年   46篇
  2015年   33篇
  2014年   43篇
  2013年   138篇
  2012年   69篇
  2011年   85篇
  2010年   53篇
  2009年   56篇
  2008年   38篇
  2007年   39篇
  2006年   44篇
  2005年   37篇
  2004年   27篇
  2003年   17篇
  2002年   24篇
  2001年   22篇
  2000年   21篇
  1999年   19篇
  1998年   17篇
  1997年   14篇
  1996年   9篇
  1995年   11篇
  1994年   8篇
  1993年   8篇
  1992年   9篇
  1991年   4篇
  1990年   4篇
  1989年   5篇
  1988年   1篇
  1987年   1篇
  1986年   1篇
排序方式: 共有1022条查询结果,搜索用时 46 毫秒
181.
Problems related with industrials effluents can be divided in two parts: (1) their toxicity associated to their chemical content which should be removed before discharging the wastewater into the receptor media; (2) and the second part is linked to the difficulties of pollution characterisation and monitoring caused by the complexity of these matrixes. This investigation deals with these two aspects, an electrochemical treatment method of an olive mill wastewater (OMW) under platinized expanded titanium electrodes using a modified Grignard reactor for toxicity removal as well as the exploration of the use of some specific analytical tools to monitor effluent phenolic compounds elimination. The results showed that electrochemical oxidation is able to remove/mitigate the OMW pollution. Indeed, 87% of OMW color was removed and all aromatic compounds were disappeared from the solution by anodic oxidation. Moreover, 55% of the chemical oxygen demand (COD) and the total organic carbon (TOC) were reduced. On the other hand, UV- Visible spectrophotometry, Gaz chromatography/mass spectrometry, cyclic voltammetry and 13 C Nuclear Magnetic Resonance (NMR) showed that the used treatment seems efficaciously to eliminate phenolic compounds from OMW. It was concluded that electrochemical oxidation in a modified Grignard reactor is a promising process for the destruction of all phenolic compounds present in OMW. Among the monitoring analytical tools applied, cyclic voltammetry and 13 C NMR are among the techniques that are introduced for the first time to control the advancement of the OMW treatment and gave a close insight on polyphenols disappearance.  相似文献   
182.
采用加速溶剂萃取法提取沉积物中的有机氯和多氯联苯,提取液用凝胶色谱法净化后用气相色谱-质谱法测定。方法在5.00μg/L~200μg/L范围内线性良好,当取样量为10.0 g时,方法检出限为0.03μg/kg~0.37μg/kg,空白样品2个质量比水平的加标回收率为70.8%~121%,测定结果的RSD为2.7%~11.5%。用该方法测定实际样品,结果 12个抽检的沉积物样品中多氯联苯均未检出,9个样品中有机氯检出。  相似文献   
183.
液相色谱法测定环境空气中酞酸酯类   总被引:1,自引:0,他引:1  
制作了半挥发性有机物中流量采样装置,使用超细玻璃纤维滤膜采样,反相液相色谱法测定环境空气中酞酸酯类,并对样品净化方式、目标化合物在气相和颗粒物上的分布规律及采样器的捕集效率进行了试验.方法在0.50 mg/L~50.0 mg/L之间线性关系良好,当浓缩体积为1.0 mL、采样体积为144 m3时,目标化合物的检出限为0.4×10-3 μg/m3~6.0×10-3 μg/m3;当采样体积为6 m3时,检出限为0.008 μg/m3~0.145 μg/m3.  相似文献   
184.
Determination of N-nitrosodimethylamine in drinking water by UPLC-MS/MS   总被引:1,自引:0,他引:1  
The method for detecting N-nitrosodimethylamine (NDMA) in drinking water using ultra performance liquid chromatography (UPLC) coupled with tandem mass spectrometry (MS/MS) was improved by optimizing the clean-up procedure to remove the matrix interference in pretreatment process, and was then applied to a survey of NDMA in both raw and finished water samples from five water treatment plants in South China. The NDMA concentrations ranged from 4.7 to 15.1 ng/L in raw water samples, and from 4.68 to 46.9 ng/L in finished water. The NDMA concentration in raw water was found to be related with nitrite concentration, and during the treatment, the NDMA concentration increased following ozonation but decreased after subsequent activated carbon treatment.  相似文献   
185.
新生产空调客车内挥发性有机物浓度水平和来源分析   总被引:1,自引:0,他引:1  
选取某厂家新生产的、下线时间不超过28d的53座新空调客车,在车辆处于静止状态下采用二次热解析-毛细管气相色谱/质谱联用法测量新空调车内挥发性有机物的分布特征和浓度水平.根据NIST02标准谱图进行匹配检索,结合色谱保留时间定性,共定性检出33种挥发性有机物,包括烷烃(15种、45.4%)、芳香类化合物(9种、27.3%)、醇(4种、12.1%),酮(3种、9.1%)、酯(2种、6.1%),且大多集中在C6~C10的范围内.新车内浓度最高的前5种挥发性有机物分别为癸烷(8.01 mg/m3)、3-甲基己烷(7.10mg/m3)、庚烷(5.10mg/m3)、异庚烷(4.20 ms/m3)和1-甲基,3-乙基苯(3,56 mg/3),总挥发性有机物TV012,52.5mR/m3.烷烃主要来源于空调车内部保温材料如聚氨酯(PU)发泡海绵或者聚乙烯(PE)发泡材料的释放,而车内检出的芳香族化合物主要来自汽车内饰用胶粘剂、密封胶等的释放.  相似文献   
186.
微波萃取-气相色谱/质谱法测定土壤中的有机氯农药   总被引:11,自引:0,他引:11  
通过微波萃取提取土壤中的有机氯农药,萃取溶液经浓硫酸脱色、佛罗里硅土柱净化,最后用气相色谱/质谱法分析.以石英砂为基体进行加标回收测定,有机氯农药的回收率在75.5%~103%之间,检出限为0.01μg/kg.  相似文献   
187.
北京大气中BTEX的观测分析与研究   总被引:7,自引:6,他引:7  
采用二步深冷浓缩与气相色谱/质谱联机对北京大气中的苯类物质(BTEX) 进行了长期连续观测.最近4年观测数据表明:日变化有双峰和3峰变化,冬、春季呈现与交通高峰期吻合的双峰变化,即上午08:00至10:00和下午17:00前后各出现一个高值;秋季日变化中,夜间22:00出现第3峰值;夏季日变化呈3峰型,最大峰值在正午前后.2000~2002年BTEX月平均总浓度为(44.1±24.5) nmol/mol(碳单位),季变化峰值出现在夏季.年际变化趋势中,北京大气BTEX的总平均浓度从 1999 年到2002年大幅度下降.  相似文献   
188.
A Gram-negative, chromium(VI) tolerant and reductive strain CTS-325, isolated from a Chinese chromate plant, was identified as Ochrobactrum anthropi based on its biochemical properties and 16S rDNA sequence analysis. It was able to tolerate up to 10 mmol/L Cr(VI) and completely reduce 1 mmol/L Cr(VI) to Cr(III) within 48 h. When the strain CTS-325 was induced with Cr(VI), a protein increased significantly in the whole cell proteins. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis revealed that this protein was a superoxide dismutase (SOD) homology. The measured superoxide dismutase activity was 2694 U/mg after three steps of purification. The SOD catalyzes the dismutation of the superoxide anion (O2·−) into hydrogen peroxide and molecular oxygen. This protein is considered to be one of the most important anti-oxidative enzymes for O. anthropi as it allows the bacterium to survive high oxygen stress environments, such as the environment produced during the reduction process of Cr(VI).  相似文献   
189.
建立了固相萃取(SPE)-超高效液相色谱/三重四极杆串联质谱(UPLC-MS/MS)同时测定地表水中8种亚硝胺类化合物的方法。水样中目标物经椰壳活性炭固相萃取小柱吸附富集,小柱经氮气吹干后采用二氯甲烷洗脱。待测样品采用Atlantis T3柱,以水-甲醇作为流动相进行梯度洗脱,大气压力化学电离源(APCI)正离子模式多反应监测方式(MRM)进行检测,内标法定量分析。8种目标物在相关线性范围内线性良好(r≥0.9950),地表水加标回收率为55.4%~90.4%,相对标准偏差为3.1%~14.3%,方法检出限为1.1 ~1.8 ng/L。本方法准确度和灵敏度高,适用于快速测定地表水中8种亚硝胺类化合物含量。  相似文献   
190.
Water-insoluble organic compounds(WIOCs) are an important fraction of atmospheric fine particulate matters(PM2.5), which could affect the climate system and threaten human health potentially. In this study, molecular characterization of WIOCs in PM2.5 were investigated by 15 T Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) with atmospheric pressure photoionization(APPI) source in positive ion mode. A total of 2573 and1875 molecular formulas were iden...  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