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   569篇
  免费   13篇
  国内免费   28篇
安全科学   62篇
废物处理   47篇
环保管理   101篇
综合类   190篇
基础理论   25篇
污染及防治   56篇
评价与监测   118篇
社会与环境   8篇
灾害及防治   3篇
  2024年   4篇
  2023年   7篇
  2022年   8篇
  2021年   8篇
  2020年   23篇
  2019年   10篇
  2018年   10篇
  2017年   11篇
  2016年   17篇
  2015年   18篇
  2014年   57篇
  2013年   36篇
  2012年   23篇
  2011年   46篇
  2010年   17篇
  2009年   31篇
  2008年   23篇
  2007年   30篇
  2006年   18篇
  2005年   11篇
  2004年   14篇
  2003年   18篇
  2002年   20篇
  2001年   15篇
  2000年   23篇
  1999年   16篇
  1998年   26篇
  1997年   16篇
  1996年   18篇
  1995年   8篇
  1994年   12篇
  1993年   7篇
  1992年   3篇
  1991年   2篇
  1987年   3篇
  1978年   1篇
排序方式: 共有610条查询结果,搜索用时 15 毫秒
191.
Turkey, due to its location in the Alpine-Himalayan belt, has numerous marble deposits. More than 250 marble types with different colours and patterns have been produced from these deposits and one hundred of these are well known around the world. One such well-known marble type is Afyon-Iscehisar. Afyon-Iscehisar is Palaeozoic in age and has been quarried since the era of the Roman empire. The Afyon region is known as one of the most important marble production and processing centres in Turkey. The Afyon province, which possesses 3.5% of exploitable marble reserves (3,872,000,000 tonne) in Turkey, yields 9% of the total marble block production. The 409 marble processing plants in Afyon produce 19% of the total slab in Turkey. As a result of marble production activities, approximately 340,000 tonne of marble waste has accumulated in the area. While some of these unshaped marble blocks are re-used and returned to the economy, the majority are discarded. There are two waste marble storage fields located in the Afyon-Iscehisar region. All of the solid and fine-grained marble waste is stored in waste marble storage fields in Susuz Bo?az? and in the nearby Iscehisar marble quarries. The ecological effects of the marble waste, which were once discharged everywhere and exhibited visual pollution, has now been reduced to a minimal level.  相似文献   
192.
Kobayashi T  Morimoto K  Tatsumi K 《Chemosphere》2008,70(11):2002-2008
Plants contain a wide variety of chemicals, some of which may have similar chromatographic behavior to polycyclic aromatic hydrocarbons (PAHs). During solid phase extraction (SPE) with Si-gel for instance, the co-elution of carotene-like colored compounds with PAHs has been observed. In this paper, liquid–liquid extraction was applied for the separation and subsequent analysis of PAHs from plant extracts. PAHs containing 2–6 rings, which include naphthalene, phenanthrene, pyrene, benzo[a]pyrene and benzo[ghi]perylene, were used as representative target chemicals. Carotene-like compounds extracted from Komatsuna (Brassica campestris) shoot by acetone followed by Si-gel treatment were incorporated as undesired components in the model matrix. Results showed the feasibility of employing either acetonitrile or 2% (w/v) KOH–methanol as solvents for high PAHs recovery and low extraction of colored fraction. For acetonitrile, 86.9–93.5% of each PAH could be recovered after three extraction cycles (relative standard deviation, RSD < 1.6%) with only about 10% co-extraction of colored fraction. For 2% KOH–methanol, PAHs recoveries ranging from 79.3% to 83.1% after five cycles (RSD < 1.5%) were achieved while the percent extraction of colored fraction was also low at 10%. The relatively higher selectivity of the solvents for PAHs over the colored fraction as well as the solubility of the matrix solution in the solvent may have contributed to these results. On this basis, liquid–liquid extraction is very useful for the pre-treatment of plant extracts for PAHs analysis.  相似文献   
193.
We report and analyze data on the PM10 fraction of airborne particles measured at five recording stations in the Brussels region from October 2002 till September 2003. These stations are representative of the various activity sectors of the Brussels urban area. The objective was the determination of the origin of the PM10 particles (particles up to 10 μm) that are recorded in that region in order to follow the EU directives concerning tolerance level of airborne particles concentration. In order to evaluate the impacts of local and external factors that inject solid particles in the atmosphere of Brussels we compared concentration data from working and not working (holidays) periods. Moreover, we also compared concentrations from periods of agricultural activity and rest in the Brabant provinces surrounding the Brussels region for various crop types. The results lead to the conclusion that the impact or urban traffic is rather limited while that of the agricultural activities is important. Moreover, there appears a clear-cut distinction between different types of crops.  相似文献   
194.
Fang HJ  Hou HQ  Xia LY  Shu XH  Zhang RX 《Chemosphere》2007,69(11):1734-1739
A combined plasma photolysis (CPP) reactor that utilizes a dielectric barrier discharge (DBD) plasma and 207 nm UV radiation from discharge-driven KrBr* excimers was designed and constructed. Gas streams containing CS2 were treated with stand-alone DBD and CPP at atmospheric pressure. In comparison to DBD, CPP greatly enhanced the removal efficiency at the same applied voltage, waste gas concentration and gas residence time. Thus the applied voltage could be reduced to a certain extent in the plasma processing of industrial wastes. Influences of the KrBr* radiation, inlet CS2 concentration and gas residence time on CS2 removal by CPP were also studied. In addition, the likely reaction mechanisms for the removal of CS2 by CPP are suggested based on the byproducts analysis. The enhanced removal efficiency and reaction mechanisms implied that the CPP process would probably be suitable for the removal of a large number of gaseous pollutants.  相似文献   
195.
固相微萃取-气相色谱法测定水中痕量有机氯农药   总被引:4,自引:0,他引:4  
建立了固相微萃取-气相色谱联用快速测定水中14种痕量有机氯农药的方法,对比研究了浸入式直接固相微萃取与顶空固相微萃取两种方式对不同有机氯农药的富集效率,优化了试验条件.方法线性关系良好,检出限为0.1 ng/L~10 ng/L,定量下限为0.2 ng/L~40 ng/L,RSD<8%,实际水样的加标回收率为67.0%~133%.  相似文献   
196.
水中微量弱极性内分泌干扰物测定方法的研究   总被引:1,自引:0,他引:1  
使用ENVITM Chrom P固相萃取小柱、双(三甲基硅烷基)三氟乙酰胺(BSTFA)衍生剂及气质联机,系统研究了水中弱极性内分泌干扰物(EDCs)的测定方法.通过正交试验,得到最佳固相萃取条件为:水样流速5 mL/min,洗脱剂为二氯甲烷,洗脱速率0.5 mL/min,洗脱剂体积6 mL.最佳衍生化条件为:BSTFA 100 μL,60 ℃,反应时间30 min.结果表明,双酚A、五氯酚、2,4-二氯苯酚、4-壬基酚、雌二醇、雌三醇、雌酮、炔雌二醇的回收率在82.4%~101.9%,检出限为0.01~0.06 μg/L.  相似文献   
197.
The amount of solid waste in the vicinity of the river Ganga increased rapidly during the festive days of Ardh-Kumbh. The initial amount of solid waste was 775.0 kg, observed on 30th January 2004 in the Har Ki Pauri area, which increased to 4,550.0 kg on the main bathing day of 4th May 2004, showing nearly a six-fold increase. The total amount of solid waste collected during nine days of observations was 23,865.0 kg. The rate of solid waste generation fell sharply during the following week, after the main bathing day, and was found to be 1,155.0 kg, which is still about 14.90% higher than the initial value.  相似文献   
198.
李国香 《交通环保》1999,20(1):34-38
针对我国在用车排放比较严重的现状,我们认为:短期内易于实现,花费不高,不用对现有车辆作重大技术变动的有效措施是完善在用车I/M计划和进行在用国的加速淘汰工作。而且,对于用率和高污染车辆,完善的I/M计划也是更有效控制机动车排放污染所必需的。  相似文献   
199.
四川省固体废物处置现状及对策探讨   总被引:2,自引:0,他引:2  
我国《固体废物污染环境防治法》(以下简称《固废法》)自1996年4月1日颁布实施8年来,在实际工作中面临了许多新的问题。因此,立法机关重新修订了《固废法》,并于2004年4月1日起生效。由此可以看出,固废的污染防治越来越得到重视。我省固体废物产生量近年来一直呈上升趋势,但其综合利用率和处置率偏低,造成的污染日趋严重。本文分别对我省一般工业固废、危险废物和生活垃圾处置现状进行分析,提出提高我省固废处置几点建议。  相似文献   
200.
陈祥彬 《福建环境》2003,20(3):27-29
该文阐述了台湾固体废物的回收利用工作通过立法进行管理固废回收市场运营,通过科技研究为废物综合利用资源化提供了有益借鉴。  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