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781.
陆钢  邢奕  宋存义 《环境工程》2007,25(6):50-52
在实验室进行了转炉除尘水脱除烟气中SO2的一系列单因素实验,重点考察了pH值、Fe离子浓度等因素对转炉除尘水脱硫效率的影响并将实验结果与他人的研究结果进行了比较分析。研究结果表明上述因素对转炉除尘水脱硫效率的影响有其特殊的规律。  相似文献   
782.
论环境规划实施的一般模式   总被引:2,自引:2,他引:0  
环境规划实施是政府相关部门根据环境保护的要求,建立组织机构,分解规划目标,在有效地分配和利用人力、财力、物力以及信息资源的条件下,采取宣传、审批、检查、监测和处罚等手段,使规划目标得以实现的动态过程.其一般模式包括宣传、实施计划、实施检查、验收批准和实施效果评估.中国当前的环境规划需要在保障资金、建立信息交流和共享机制、提高公众的参与水平、人员培训和技术支持、完善行政审批和行政问责机制等方面予以加强,并应尽快建立环境规划的法规体系.  相似文献   
783.
我国城市地下水开采诱发的灾害及对策探讨   总被引:1,自引:0,他引:1  
宋永能 《灾害学》1992,7(3):48-52
本文通过综合全国各地水文地质灾害现象,将其归纳为四类:(1) 地下水下降漏斗扩大;(2) 地面沉降;(3) 地下水质恶化;(4) 地裂缝和地塌陷。同时分析了这些灾害的形成机制、危害程度以及经济损失情况,并提出了一些相应的治理对策。  相似文献   
784.
杨毅  宋早雪  周丽萍  韩爱红 《灾害学》2007,22(3):114-119
针对地震、恐怖袭击等突发性事件引起的次生火灾对大型建筑的破坏特点,比较了大型建筑与普通建筑在结构抗火性能上的差异;利用轴向非均匀温度应力模型,对大型建筑构件的抗火性能与结构抗火计算进行了分析,疏理归纳出了部分性能特征;提出了一套用于这类火灾特点的构件抗火计算理论方法。  相似文献   
785.
石油石化行业工艺复杂,存在的有害因素种类繁多,一旦发生急性中毒其涉及面广、影响大,有时可造成严重危害。文章较为详细地介绍了该行业存在的主要有毒物质以及发生急性中毒事故的必要条件和特点,阐述了有毒物质侵入人体的途径主要为直接接触或通过呼吸,最后针对一般情况、吸入性中毒、直接接触造成危害的情况介绍了相应的现场急救处理措施。  相似文献   
786.
Air quality in underground spaces has seldom been evaluated in Korea. Accordingly, the current study recently evaluated asbestos exposure among Seoul metropolitan subway workers during the renovation of the subway's air-conditioning system. To identify possible routes of asbestos exposure, suspected sources, including gaskets, ceiling boards, ceiling materials, and dust settled inside ducts, were all sampled. Personal air samples were also taken to evaluate any asbestos exposure during the renovation. The asbestos fibers found in the samples were analyzed using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray analyzer (EDX). Twelve out of eighteen bulk samples contained asbestos, the majority of which was chrysotile fibers. Asbestos was detected in 9 out of 72 personal air samples and the level ranged from 0.003 to 0.02 fibers/cm(3). While asbestos levels were below Korean occupational limit of 2 fibers/cm(3), they were still detectable and therefore further monitoring would be appropriate.  相似文献   
787.
Recently, a worker with lung carcinoma and a metastatic brain tumor was diagnosed as having a work-related disease. He had been employed in a non-asbestos textile company for 25 years. Consequently, to identify and explore possible causative agents for lung cancer in a non-asbestos textile manufacturing company and establish a causal relationship between exposure and lung cancer, an epidemiological investigative study was conducted and the work processes the worker was engaged in were examined. Air samples were taken from the workplace and during the drilling processes, and a suspected causative material was analyzed. The study revealed that the subject had been employed in the non-asbestos textile manufacturing company for 25 years from 1973 and his responsibilities included repairing spinning machines. In particular, the subject was involved in drilling B-bushings that were used to protect against gear abrasion in the spinning machines. An analysis of the B-bushings using a transmission electron microscope equipped with an energy dispersive X-ray analyzer indicated that they contained crocidolite asbestos fibers. Air samples obtained when drilling the B-bushings clearly indicated that the subject had most likely been exposed to crocidolite fibers when installing the B-bushings in the spinning machines. The frequency and duration of the work suggested that there would be a sufficient degree of exposure to crocidolite fibers to cause lung cancer. Except for smoking and asbestos exposure, no other chemical exposure was suspected for developing lung cancer in the workplace. Smoking appeared to be more of a potentiating risk factor in conjunction with the asbestos exposure. Accordingly, this case may provide significant evidence in identifying the cause of the mesothelioma or lung carcinoma found among workers in non-asbestos textile manufacturing companies elsewhere.  相似文献   
788.
Behavior of Po in fresh waters was examined in laboratory culture experiments using fresh water collected from a small pool, Xi river and Xiqing lake, showing formation of volatile Po compounds followed by emission to air. Addition of tryptone to the fresh water cultures increased the emission of Po considerably along with a growth of microorganisms, suggesting a connection of chemoheterotrophs to Po emission. Participation of photoautotrophs was also considered because Po emission was increased when NaHCO3 was added to the fresh water cultures. The emission behavior of Po and S in these experiments appeared in different ways. The quantity of Po emitted was comparable to the previous culture experiments (Momoshima, Song, Osaki & Maeda, Environ. Sci. Technol., 35, 2956-2960, 2001) in which artificial culture medium containing 3% NaCl was used and inoculated with sea sediment extract. The biological support for Po emission, thus, would be a general phenomenon in fresh water as well as a seawater environment and is possibly a source for atmospheric Po.  相似文献   
789.
废高磁合金钢中钴、镍的分离和利用   总被引:1,自引:0,他引:1  
岳松 《四川环境》2000,19(4):29-31
用硫酸、盐酸和硝酸溶解废高磁合金钢、并将Fe^2 氧化为Fe^3 。先用黄铁矾法除去大部分铁,用尿素除去少量的铁及铝、钛、铜;最后在NH3-NH4Cl体系中分离钴、镍,并制成相应的盐。钴、镍的回收率分别国81.5%、89.7%。  相似文献   
790.
空难对湿地浮游植物的影响   总被引:5,自引:4,他引:1  
浮游植物已经广泛应用于环境影响评价.包头"11·21"空难对南海子浮游植物的种类、种群结构、优势种(属)、细胞密度、种类数和细胞密度的空间分布产生了重要影响.调查表明:南海子浮游植物有5门27属,其中蓝藻门有5个属,隐藻门有2个属,硅藻门有5个属,裸藻门有2个属,绿藻门有13个属;蓝藻门和绿藻门为南海子的优势门类,其中微囊藻、平裂藻和栅藻为优势属;南海子浮游植物的Margelef种类丰度指数为0.9646,Shannon-Wiener多样性指数为0.7647,空难后南海子水体污染严重;浮游植物(特别是富营养化指示藻类)的种类数和细胞密度的高值区主要出现在污染水域.南海子水质的浮游植物生物学评价结果表明,空难事故后南海子水体已属于严重富营养化水平.   相似文献   
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