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991.
采用富集培养及平板分离方法从成都某污水处理厂活性污泥中筛选出一株具有絮凝活性的菌株SNUX-1,经形态特征及16S rRNA鉴定该菌株为约氏不动杆菌(Acinetobacter johnsonii).对该菌株絮凝活性分布及在不同生长条件下所产絮凝剂的絮凝率进行了研究,并对其絮凝剂成分进行了分析.结果表明,该菌株所产微生物絮凝剂为胞外产物,显色剂显色结果表明,该絮凝剂不含蛋白质成分,含有糖类成分;在以蔗糖为碳源、培养基初始pH值为8、以氯化铜为助凝剂的条件下培养12 h,该菌株所产微生物絮凝剂的絮凝率最高,达96.71%,可作为治理环境污染的菌种资源.  相似文献   
992.
采集了长焰煤粉并提取其中的胶体,用激光粒度仪、红外光谱仪、扫描电镜和Zeta电位仪对煤基胶体的特征进行了定性和定量表征,研究了煤基胶体在石英砂的多孔介质柱中的运移特征及p H值、阳离子等环境因子的影响。结果表明,该方法提取煤基胶体的实测粒径与理论计算粒径基本吻合,煤基胶体表面具有丰富的褶皱和极其丰富的孔隙结构并呈片状,煤基胶体的化学组成以芳香烃为主,在试验范围内,煤基胶体的Zeta电位在-34.0~-21.2 e V,随p H值升高而下降。溶液p H=7时,煤基胶体在多孔介质中的运移能力最强,c/c0为0.664,增加p H值或降低p H值,运移能力下降。Ca离子对煤基在多孔介质中的运移具有明显的抑制作用,当离子强度IS(Ca Cl2)由0.001 mmol/L增加到0.1 mmol/L时,胶体悬液c/c0从0.569降至0.129。  相似文献   
993.
On the basis of a unique firm-level dataset from the German manufacturing sector, this paper empirically examines the determinants of environmental and non-environmental product and process innovations. The micro-econometric analysis with multivariate probit models points to an extremely high relevance of R&D activities for all technological innovation types, as well as to the relevance of a few market pull factors. The estimation results additionally reveal the importance of organisational measures for environmental product and process innovations. In this regard, not only certified environmental management systems, but also specific process- and product-related environmental organisational measures and even general organisational measures, such as the certification of a quality management system according to ISO 9001, play a crucial role. The estimation results therefore suggest the encouragement of firm-internal R&D activities and organisational measures by (environmental) policy in order to stimulate environmental technological innovations, which are able to both limit the environmental burden and contribute to the technological modernisation of the economy.  相似文献   
994.
双酚F(BPF)和双酚S(BPS)作为双酚A(BPA)替代品广泛使用,然而有关BPF和BPS的毒性数据非常有限。采用系列浓度的BPA、BPF、BPS溶液,暴露黑斑蛙胚胎和蝌蚪96 h,通过半致死浓度(LC50)、最小生长抑制浓度(MCIG)和致畸率等指标比较3种化合物的急性毒性。结果显示:100 mg·L-1BPS未导致黑斑蛙胚胎及蝌蚪畸形和死亡。BPA和BPF对黑斑蛙胚胎的96h-LC50分别为7.68 mg·L-1和7.99 mg·L-1,MCIG分别为4.47 mg·L-1和4.77 mg·L-1,最大致畸率为33.33%;对蝌蚪的96 h-LC50分别为9.00 mg·L-1和9.52 mg·L-1。依据《化学农药环境安全评价准则》的毒性分级标准,判定BPA和BPF的毒性等级为中毒,BPS的毒性等级为低毒。表明BPF急性毒性与BPA相当,BPS急性毒性低于BPA。本研究数据可为BPF、BPS作为BPA替代品的生产和使用以及相应的环境管理提供毒理学参考。  相似文献   
995.
Oil pollution is one of the major factors causing environmental deterioration. Bioremediation of oil contaminated environments by microorganisms attracts much research attention. This study aimed to screen efficient oil-degrading bacteria from oil contaminated soil and analyze their characteristics and catabolic genes. Oil-degrading bacteria were screened from oil contaminated soil in minimal medium containing crude oil and identified by morphological, physiological and biochemical characteristics and 16S rDNA sequence analysis. Their growth and degradation characteristics were studied with ultraviolet spectroscopy and GC-MS analysis. The surfactant production was studied by adopting culture method. The major oil-degrading related genes were detected by t he PCR a mplification. As a result, t hree oil-degrading bacteria strains named KB1, 2182 and JC3-47 were isolated from the oil contaminated soil samples. The strains could use crude oil as the sole carbon source to degrade oil with a degrading rate of 41.02%, 32.26% and 55.90%, respectively, when cultured in minimal medium containing crude oil for 3 days. The bacteria were identified to belong to genus Rhodococcus. With 100% similarity of 16S rDNA sequences of the three strains with known ones of Rhodococcus, KB1 was preliminarily identified as Rhodococcus erythropolis, 2182 as Rhodococcus equi, and JC3-47 as Rhodococcus qingshengii. They grew well at 10-50 °C, with the initial pH of 3-9 and the NaCl concentration of 0-5%. The optimal temperature for bacterial growth was 35 °C, 35 °C and 30 °C respectively. KB1 and 2182 could grow at pH 2 and 9.0% of NaCl. The bacteria grew well in broth containing different organic substrates as sole carbon source, such as n-dodecane, n-octadecane, benzene, methylbenzene, xylene and naphthaline. KB1 and JC3-47 could grow well in broth containing pyrene. GC-MS analysis revealed that the bacteria could effectively degrade medium- and long-chain alkane components in crude oil. The bacteria produced biosurfactants and decreased the surface tension of the culture broth. They also showed adhesion activities to n-hexadecane. The oil-degrading related genes such as alkane monooxygenase, aromatic-ring-hydroxylating dioxygenase and catechol dioxygenase genes were detected in all the three strains. Besides, biphenyl dioxygenase genes were detected in KB1 and 2182. The isolated Rhodococcus spp. strains could effectively degrade petroleum hydrocarbons with high adaptabilities to extreme environments such as high salt and low temperature. They are supposed to be applied broadly in the bioremediation of oil contaminated soil in such environments.  相似文献   
996.
关于固体废弃物处理技术研究   总被引:1,自引:0,他引:1  
固体废弃物即是在生产与生活的过程中所产生的固态或者半固态物质,一般来说包括了工业垃圾、生活垃圾以及危险废弃物等。固体废弃物如果不能够进行及时有效的处理,则很容易对环境产生影响,其对于生态环境的影响一般是间接性的、潜在的以及长期性的综合影响。现结合笔者实际研究,分析了常见固体废弃物的分类,并就当前我国的固体废物处理技术进行了论述。  相似文献   
997.
To evaluate bacterial community variation in the mushroom shiro of Suillus granulatus during fruiting, we collected soil samples from the mushroom shiro in the pine (Pinus tabuliformis) forest of mountainous area in Beijing from May to November and evaluated the bacterial community using polymerase chain reaction - denaturing gradient gel electrophoresis (PCR-DGGE). Total soil DNA was extracted using a commercial soil DNA isolation kit. PCR amplification and DGGE were performed using bacterial universal primers 338F and 518R. The specific bands were excised from the gel and sequenced. The results revealed that soil bacterial community maintained considerably high level and changed seasonally with the mushroom fruiting. In total, 53 bands of DGGE profiles were sequenced and divided into 5 phyla (Acidobacteria, Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria and 22 genera (Acidobacterium, Aminobacter, et al). Species from Proteobacteria and Acidobacteria were the dominant bacterial groups sharing considerably high relative abundance, while class a-Proteobacteria was the most abundant group. The variation of the relative abundance of γ-Proteobacteria species was consistent with the mushroom fruiting season. The relative abundance of Acidobacteria species obviously increased before mushroom flush (in July). The fruiting of S. granulatus and the relative abundance of γ-Proteobacteria were correlated with each other. The present study provided a basis for conservation and domestication of mushroom S. granulatus.  相似文献   
998.
Micro-organism with efficient desulfurization performance is a key factor in the biological desulfurization technology. This study aimed to seek such a sulfur-oxidizing strain and understand its desulfurization mechanism. Wastewater in a sewage station of natural gas purification plant was used to screen the sulfide-oxidizing strain, and to identify it based on sequence similarity analysis of 16S rDNA and the morphological characteristics. Thiosulfate was used as substrate for investigating the sulfur oxidation performance and salinity tolerance; the OD600, content change of thiosulfate, sulfate, sulfur, pH and total alkalinity in the cultural system were also investigated. The strain DS-B was found to share the highest sequence similarity with Thioalkalivibrio thiocyanoxidans ARh2, therefore determined as Thioalkalivibrio. At the optimum temperature of 35 °C for growth and degradation, the removal efficiency of thiosulfate could reach 98.7% after 7 days. Strain DS-B had strong resistance to thiosulfate, and the optimal concentration of S2O32- was 2 × 104 mg/L. The analysis for sulfur oxides showed that it could oxidize thiosulfate by the pathway of S2O32-→SO42- / S2O32- → S → SO42-. Therefore the strain DS-B is a sulfur-oxidizing bacterium with great application prospect for its strong salt tolerance and conspicuous removal capability for thiosulfate.  相似文献   
999.
针对关于城市室内环境污染治理的探讨问题,提出选择治理手段来控制室内环境污染,保障人体健康显得尤为重要.介绍了室内环境污染治理技术,如光催化技术、物理吸附技术、高温熏蒸技术、臭氧和空气负离子净化技术,探讨了室内污染治理存在的误区,包括过度信赖活性炭、过度信赖植物吸附、受产品宣传误导,提出了如何选择室内污染治理手段,主要包括从根本上杜绝污染、根据装修材料选择治理手段和根据房间的布局及使用功能选择治理手段.  相似文献   
1000.
随着工业化和城市化进程的加快,环境污染问题已成为生态文明建设亟需解决的重要问题.生态文明是对农业文明和工业文明的超越,代表了更为高级的人类文明形态.生态文明建设是体现经济、社会、环境可持续发展以及人与自然和谐共存的重要战略决策.本文从环境质量改善及污染控制的有效性方面,深入剖析了技术创新、产业升级与污染控制之间的互作效应关系,并探讨了有效的实现方式.研究结果旨在为生态文明建设的有效实施和顺利展开提供借鉴和参考价值.  相似文献   
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