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101.
为研究间歇运行式生物滴滤池对油漆生产厂废气净化能力,建立一座中试规模生物滴滤池(BTF),接种降解菌群,采用8 h/d运行方式净化某油漆厂包装车间废气,并用PCR-DGGE技术揭示BTF细菌群落结构与工艺运行条件间的联系。油漆厂包装车间废气中挥发性有机物(VOCs)主要为甲苯、乙苯、混合二甲苯(间、对和邻二甲苯),BTF对甲苯、乙苯、混合二甲苯最大去除率分别为88.8%、83.7%和86.3%。DGGE分析显示,BTF稳定运行时,主要优势菌相对丰度较为稳定(F,P>0.05),其细菌多样性显著低于启动期(F,P>0.05);同时,下层填料细菌多样性高于上层填料,其细菌结构变化也较上层明显;另外,提升培养液浓度至2倍和4倍对菌群结构亦无显著影响。  相似文献   
102.
Polybromodiphenyl ethers (PBDEs) are one of the many toxic chemicals present in the environment and in the food we eat every day, being fish one of the main sources of persistent organic pollutants in our diet; like other lipid-related contaminants, they are of concern since they can bioaccumulate and biomagnify through the trophic chain. We published a study focused on the dietary uptake of dioxins and furans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) in a set of samples of Spanish farmed turbot (Blanco et al., 2007). In the present paper, we extend the study to PBDEs to provide more information about the uptake and transfer from feed to fish of halogenated contaminants. PBDEs in the feeds (2.35-4.76 ng g(-1)) were reflected in turbot fillets (0.54-2.05 ng g(-1)): predominant congeners were tetra-BDE 47, penta-BDEs 99 and 100. It is remarkable that tetra-BDE 49, accounting for only 2% in the feed, contributed to 15% of total PBDEs in turbot fillets. Dietary net accumulation values, 30-45%, showed that tri-, tetra-, penta- and hexa-BDEs were as efficiently transferred into turbot as dl-PCBs and tetra- and penta-chlorinated PCDD/Fs. Lipid-normalized biomagnification factors relating concentration in fish and in feed, BMFs>1 were obtained, except for BDE 209. BDE 49 accumulation, 90%, was possibly contributed by metabolism of higher brominated BDEs. Implication in aquaculture management is a need for uncontaminated fish feed to offer safe products.  相似文献   
103.
从钾矿性质和浮选技术2个方面对盐湖含泥钾矿进行资源化利用研究,首先运用X射线荧光光谱、X射线衍射和扫描电镜对含泥钾矿的矿泥化学组成及其结构特征进行了分析,其次选用盐酸十八胺和煤油为浮选药剂,对浮选法脱除钾矿中泥进行了研究.结果表明,盐湖矿泥中70%以上为以长石、粘土和粉砂等为主的硅铝酸盐;矿泥多充填包裹于盐类矿物粒晶间...  相似文献   
104.
TiO2/凹凸棒土复合催化剂的制备及光催化降解活性大红   总被引:2,自引:0,他引:2  
以凹凸棒土作为载体,以 TiOSO4为钛源,采用超声分散-再沉淀法制备了 TiO2粒径为 10 nm 左右的锐钛矿型 TiO2/凹凸棒土复合催化剂.并采用 X 射线衍射仪、透射电子显微镜、X 射线能谱仪对复合催化剂进行了表征.制备复合催化剂的最佳条件:凹凸棒土与 TiO2的质量比为 1:3.0,煅烧温度为 450 ℃....  相似文献   
105.
As an economically developing country, Turkey has very well operated integrated solid waste management applications structured on modern facilities, besides over 2,000 scattered open dump areas in the country. Integrated waste management applications seem eligible for the metropolitan cities like Istanbul and Izmit (Kocaeli). Attempts have not been encouraging for the scattered regional settlements using central storage sites due to financial shortages and received rejections from nearby settlements. Small-scale compact solid waste management systems with materials recycling and composting can be more suitable alternatives in the small-scale regional settlements. The major constituents of municipal solid waste are organic in nature and approximately a quarter of municipal solid waste is recyclable. Although paper, including cardboard, is the main constituent, the composition of recyclable waste varies strongly by the source or the type of collection point. Solid wastes need primary treatment in order to be suitable for incineration and composting. Turkey needs to give more emphasis on the usage of modern solid waste removal technologies to overcome the overgrowing solid waste disposal problems.  相似文献   
106.
探讨装备制造企业按照"装备制造4R"原则,制定循环经济发展思路、统筹规划产业发展路径、培育战略性新兴产业;实施传统产业升级和技术创新;通过组织企业内各工艺之间的物料循环,减少生产过程中物料和能源的使用量,最大限度地利用可再生资源,达到发展循环经济的目的.  相似文献   
107.
西让我们坐在赤裸的土地上哭泣捶胸跺足如丧考批为了先祖笔下曾有的参天古木为了往昔丰茂无边的水草让我们坐在城市的水泥路面哭泣纵使我们泪流似海也不会有一滴渗进城市坚硬的地表在这片留不住水的土地上不知人们将如何留下他匆匆的印痕让我们坐在龟裂的河床上哭泣为了永恒千年的芦沟晓月再也无法映着碧波对镜自怜为了母亲再也挤不出甘甜的乳水哺育两岸饥渴的人民让我们坐在赤裸的土地上哭泣让我们坐在每一株无法成活树木旁哭泣假若我的血液能让一裸树苗复活那么就请取走我的全部吧我的自然之母在你宽厚的原野上我只愿能化为一把苍凉的沃土…  相似文献   
108.
The aim of this work was to determine the optimal conditions for the decolorization and the detoxification of two effluents from a textile industry—effluent A (the reactive dye bath Bezactive) and effluent B (the direct dye bath Tubantin)—using a laccase mediator system. Response surface methodology (RSM) was applied to optimize textile effluents decolorization. A Box–Behnken design using RSM with the four variables pH, effluent concentration, 1-hydroxybenzotriazole (HBT) concentration, and enzyme (laccase) concentration was used to determine correlations between the effects of these variables on the decolorization of the two effluents. The optimum conditions for pH and concentrations of HBT, effluent and laccase were 5, 1 mM, 50 % and 0.6 U/ml, respectively, for maximum decolorization of effluent A (68 %). For effluent B, optima were 4, 1 mM, 75 %, and 0.6 U/ml, respectively, for maximum decolorization of approximately 88 %. Both effluents were treated at 30 °C for 20 h. A quadratic model was obtained for each decolorization through this design. The experimental and predicted values were in good agreement and both models were highly significant. In addition, the toxicity of the two effluents was determined before and after laccase treatment using Saccharomyces cerevisiae, Bacillus cereus, and germination of tomato seeds.  相似文献   
109.
The noxious effects of low or effective dose exposure to single or mixed pesticides on macrophage activity and the lymphohematopoietic organs were investigated. Male Wistar rats were orally exposed to dichlorvos, dicofol, endosulfan, dieldrin and permethrin, either as single or combined mixtures during a 28-day study containing eight groups: one group received a semipurified diet (non-treated); two groups received a semipurified diet containing low dose mixture (dieldrin 0.025 mg/kg, endosulfan, 0.6 mg/kg, dicofol 0.22 mg/kg, dichlorvos 0.23 mg/kg, permethrin 5 mg/kg) or an effective dose mixture (dichlorvos 2.3 mg/kg, dicofol 2.5 mg/kg, endosulfan 2.9 mg/kg, dieldrin 0.05 mg/kg and permethrin 25.0 mg/kg), respectively; the other five groups received a semipurified diet containing each single pesticide in effective doses. At sacrifice, the thymus, spleen, mesenteric lymph nodes, Payer's patches and bone marrow were removed for histological analysis. Peritoneal macrophages were obtained to determine the phagocytosis and spreading indexes and tumoral necrosis factor alpha (TNF-α), nitric oxide (NO) and H2O2 production. Exposure to pesticide mixtures did not alter the percentage of macrophage phagocytosis and spreading, TNF-α production or the NO and H2O2 release when compared to the non-treated group. Neither was there any apparent evidence that a pesticide mixture at low or effective doses altered the histological structure of the lymphohematopoietic organs. The findings indicate that short-term treatment with pesticide mixtures did not induce an apparent immunotoxic effect in male Wistar rats.  相似文献   
110.
本文论述了城市汽车空气污染研究的目标、基本方法及城市汽车污染控制区的划分原则和方法.汽车类型流动源采用整个控制区平均浓度作为分析对比的基础不合适,应该专门研究确定基准控制点.为了合理选择确定控制计算点,提出3种方法:峰值法、核心区和重点控制区法、9点平均法.9点平均法可以有效增加各类污染源的敏感点,同时又可避免增加该点位影响过大的缺陷.这种方法在其他类型大气污染源控制中也能发挥作用.  相似文献   
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