全文获取类型
收费全文 | 8964篇 |
免费 | 863篇 |
国内免费 | 2533篇 |
专业分类
安全科学 | 690篇 |
废物处理 | 1052篇 |
环保管理 | 1413篇 |
综合类 | 5908篇 |
基础理论 | 1243篇 |
环境理论 | 6篇 |
污染及防治 | 1370篇 |
评价与监测 | 462篇 |
社会与环境 | 179篇 |
灾害及防治 | 37篇 |
出版年
2024年 | 6篇 |
2023年 | 93篇 |
2022年 | 170篇 |
2021年 | 229篇 |
2020年 | 296篇 |
2019年 | 238篇 |
2018年 | 238篇 |
2017年 | 308篇 |
2016年 | 417篇 |
2015年 | 431篇 |
2014年 | 638篇 |
2013年 | 835篇 |
2012年 | 800篇 |
2011年 | 770篇 |
2010年 | 554篇 |
2009年 | 622篇 |
2008年 | 481篇 |
2007年 | 642篇 |
2006年 | 669篇 |
2005年 | 522篇 |
2004年 | 434篇 |
2003年 | 457篇 |
2002年 | 402篇 |
2001年 | 315篇 |
2000年 | 314篇 |
1999年 | 270篇 |
1998年 | 237篇 |
1997年 | 194篇 |
1996年 | 168篇 |
1995年 | 156篇 |
1994年 | 94篇 |
1993年 | 78篇 |
1992年 | 68篇 |
1991年 | 55篇 |
1990年 | 31篇 |
1989年 | 17篇 |
1988年 | 14篇 |
1987年 | 21篇 |
1986年 | 10篇 |
1984年 | 7篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 9篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 3篇 |
1973年 | 5篇 |
1971年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
42.
从安全性和运营角度对油库选址的影响因素及评价指标分析对油库的安全稳定及有效运营具有重要的意义。该文选取与安全和运营有关的人口企业数量、安全管理能力、消防设施规划、地形地质条件、铁路公路数量、市场投资收益、政策支持情况等影响因子进行重要性及合理程度分析,综合运用安全度与运营格局影响因素多元耦合关系,构建了油库区安全与运营评价体系,改进了原有的模糊层次法评价模型,并对某油库区安全度与运营格局进行了评估验证。结果表明:利用改进模糊层次法能够较好地评价不同地址的优先级,评价模型具有一定应用性,能够对不同地址的特点及评价权重进行有效分析,可见油库选址优先级评价方法是实用且有效的。该研究方法及结果可以为油库区地址的优选提供一定参考与建议。 相似文献
43.
RM. Thirupathi R. Ben Ruben Jiju Antony 《International Journal of Sustainable Engineering》2019,12(2):95-107
Application of appropriate environmentally conscious manufacturing strategies enables the sustainable development of products and processes. Automotive component manufacturers recognise the potential of applying appropriate strategies for attaining Triple Bottom Line benefits. In this context, three strategies such as eco-efficiency, waste minimisation and material efficiency are being applied to minimise environmental impacts associated with the manufacture of automotive products and its associated processes. A case study of an automotive component manufacturing firm has been exemplified. After conducting the study, the potential environmental impact was reduced by 20% and eco-efficiency was improved by 13%. Further, improvements have been observed in terms of overall resource consumption and material efficiency. The overall power consumption was reduced by 18% and weight of the component was reduced by 11%. The study aimed at improving the sustainable performance of product by incorporating green and environmentally friendlier manufacturing practices.
Abbreviations: USEPA: United Nations Environmental Protection Agency; OECD: Organisation for Economic Co-operation and Development; WBCSD: World Business Council for Sustainable Development; Eco-QFD: Environmental Quality Function Deployment; WCED: World Commission on Environment and Development; LCA: Life Cycle Assessment 相似文献
44.
Diversity of antibiotic resistance genes and encoding ribosomal protection proteins gene in livestock waste polluted environment 总被引:1,自引:0,他引:1
Chunyan Li Cheng Jiang Zhiyang Wu Xuejiao An Hailan Wang 《Journal of environmental science and health. Part. B》2018,53(7):423-433
The rapid development and increase of antibiotic resistance are global phenomena resulting from the extensive use of antibiotics in human clinics and animal feeding operations. Antibiotics can promote the occurrence of antibiotic resistance genes (ARGs), which can be transferred horizontally to humans and animals through water and the food chain. In this study, the presence and abundance of ARGs in livestock waste was monitored by quantitative PCR. A diverse set of bacteria and tetracycline resistance genes encoding ribosomal protection proteins (RPPs) from three livestock farms and a river were analyzed through denaturing gradient gel electrophoresis (DGGE). The abundance of sul(I) was 103 to 105 orders of magnitude higher than that of sul(II). Among 11 tet-ARGs, the most abundant was tet(O). The results regarding bacterial diversity indicated that the presence of antibiotics might have an evident impact on bacterial diversity at every site, particularly at the investigated swine producer. The effect of livestock waste on the bacterial diversity of soil was stronger than that of water. Furthermore, a sequencing analysis showed that tet(M) exhibited two genotypes, while the other RPPs-encoding genes exhibited at least three genotypes. This study showed that various ARGs and RPPs-encoding genes are particularly widespread among livestock. 相似文献
45.
Research on the micro- and macrocharacteristics of different metamorphic degrees of coal helps improve the control and protection techniques used during spontaneous combustion. Nine coals with different properties were thoroughly investigated in this study. Fourier transform infrared spectroscopy and a self-designed temperature-programmed oil bath experimental system were adopted to analyze the molecular structure and macrocharacteristic parameters of the spontaneous combustion of coal. Additionally, the influence of particle size on spontaneous combustion was considered. Various functional groups were employed as microcharacteristic parameters to capture the principal active groups in oxidation. The gas production rate, oxygen consumption rate, gas concentration, heat energy release rate, and characteristic temperatures were evaluated as macrocharacteristic parameters to investigate the changes in coal during oxidation. The results establish that the microcharacteristics of coal molecules determine the degree of spontaneous combustion based on intrinsic properties and that changes in the macrocharacteristics of the spontaneous combustion of coal reflect the microstructural changes. The contents of the hydroxyl groups, carbonyl groups, alkyl ether and aryl ether in the coal molecules gradually decrease with the metamorphic increase. Oxygen-containing functional groups have higher reactivities and easily react with oxygen, causing the macroparameters, such as the oxygen consumption rate, the gas generation rate and the heat energy release rate, to consistently decrease with the increase of the metamorphic degree. Small-particle-size coal molecules have more active aliphatic hydrocarbons, oxygen-containing functional groups and a larger specific surface area, increasing the chances of adsorbing the oxygen of active groups and promoting the reaction between coal and oxygen. The experimental results indicate that coal samples with higher metamorphic degrees or larger sizes exhibit lower tendencies toward spontaneous combustion. Evaluation of the spontaneous combustion of coal based on a temperature-programmed oil bath experimental system is of great practical importance for preventing the spontaneous combustion of coal during storage, processing and utilization and can serve as a convenient reference for production safety in mining applications. 相似文献
46.
Kurt E. Richardson Nelson A. Cox Doug E. Cosby Mark E. Berrang Nicole L. Holcombe Cheryl E. Weller 《Journal of environmental science and health. Part. B》2019,54(4):313-316
The pH of Salmonella pre-enrichment media can become acidic (pH 4.0–5.0) when feeds/ingredients are incubated for 24?h. Salmonella in feed that have been stressed by heat and desiccation exhibit different pH tolerances than non-stressed cultures. Acidic conditions can result in cell injury/death and affect biochemical pathways. In this study, eight serotypes of Salmonella were grown in sterile meat and bone meal that was subjected to desiccation and heat stress. Cultures of non-stressed and stressed isolates were subsequently exposed to acidic pH from 4.0 to 7.0 in 0.5?pH increments (3 replicates/pH increment) in citrate buffer. At 6 and 24?h, serial dilutions were plated in duplicate on XLT-4 (xylose lysine tergitol-4) agar. Four serotypes showed an impaired ability to decarboxylate lysine on XLT-4. This inability to decarboxylate lysine was dependent on isolate, stress status, and incubation time. When the isolates’ ability to decarboxylate lysine was examined using biochemical tests, cultures were found to be able to decarboxylate lysine with the exception of S. Infantis. This suggests that XLT-4 contains a biochemical stressor(s) which affects the rate of decarboxylation by these Salmonella. These results suggest that acidic conditions may influence the detection and confirmation of Salmonella in feed. 相似文献
47.
丁基黄原酸是水质监测的重要项目之一。水中丁基黄原酸的测定,在样品采集保存、前处理及仪器分析各阶段都存在一定的技术难点。实际分析时很容易出现测定结果不理想,甚至定性定量错误等问题。结合实验对丁基黄原酸测定中容易出现的问题及注意事项进行探讨,正确区分丁基黄原酸及其盐,有效保存样品,采用低损失的前处理方法以及选择性好的分析仪器,有利于提高丁基黄原酸测定的准确性。众多丁基黄原酸测定方法中,液相色谱质谱法、离子色谱法以及液相色谱法在选择性和灵敏度方面更具优势,也可用于其他方法检出丁基黄原酸时对测定进行确认。 相似文献
48.
Meryem Hadidi Bouchaib Bahlaouan Fatimazahra Boutaleb Ghita Radi Benjelloun Alla Silkina Said El Antri Nadia Boutaleb 《环境质量管理》2023,32(4):255-265
The increase in animal and agro-industrial production must be accompanied by the development of appropriate waste and by-product management strategies. Anaerobic digestion is a promising approach to recycle these wastes and reintegrate them into the economic production cycle of biogas and biofertilizer. In order to improve the performance of the anaerobic mesophilic digestion of abundant agro-industrial wastes constituted by potato peel (PP), and poultry waste (PW) and study the contribution of bovine bone meal (BB) as additive rich in phosphorus, which can help to neutralize the acidity of the substrate. The 10-point simplex-centroid design and the isoresponse surfaces strategy were used. This study demonstrated that in mesophilic bio-digestion, the using bovine bones in admixture with agroindustrial residue provided for the proper balance of chemical components required for proliferation of microbiological agent of bioconversion, which also resulted in an increase in biogas production capacity. The best formula was so composed by 66.67% bovine bone, 16.67% potatoes peel, and 16.67% poultry waste. The stability was achieved here after only 12 days. The digestate generated from it was fulfilled with the microbiological and chemical requirements for safety defined by the NF U44-551 standard. Germination test revealed that this optimal produced digestate, did not hinder growth, in fact, almost 85% of seed was germinated. Finally, fertilization experiments prove that this digestate can boost the growth of bell pepper (Capsicum annuum). 相似文献
49.
Wan Nur Dinie Hidayah Wan Azman Mohd Amir Asyraf Mohd Hamzah Maizatulakmal Yahayu Zainul Akmar Zakaria 《环境质量管理》2023,33(1):13-22
The rise in the number of fungi that resisted antifungal action is of serious concern nowadays. In this study, the potential of acid condensate (AC) produced from microwave-assisted pyrolysis of palm kernel shell (PKS) was investigated for its antifungal properties through molecular docking evaluation. The phenolic-rich AC was determined for its chemical compositions using the GC–MS analysis where compounds with the highest phenolics content were further evaluated (using the Autodock Tools 1.5.7) for its potential enzymes/protein binding properties. From the GC–MS analysis, catechol, guaiacol and syringol were present at highest percentages. This directly correlates with results obtained from the molecular docking works where all these ligands managed to bind (indicated by H-bond, π-stacking, hydrophobic interaction) with some of the amino acid at the active sites which indicate its potential to inhibit substrate binding of this enzyme. As a conclusion, this study demonstrated the potential use of AC from agricultural biomass such as PKS as a natural-based antifungal agent that can reduce environmental and health impacts. 相似文献
50.
高效复合菌在木薯酒精废液处理中的应用研究 总被引:1,自引:0,他引:1
对酒精废液生物处理反应器内颗粒污泥中的微生物进行分离纯化.分离出的8株高效优势菌,初步鉴定结果:1号为皮杆菌属;2号为棒杆菌属;3号、4号为微小杆菌属;5号为乳杆菌属;6号为纤维单胞菌属;7号为丙酸杆菌属;8号为红长命菌属.对8种纯化后的菌株进行混合培养,确定了复合菌群生长最佳培养温度为37℃,最适pH值为6.8.在处理过程中投加适量葡萄糖、硝酸铵和微量元素能够提高复合菌群的处理效果.最佳添加量为:葡萄糖0.5g/L,硝酸铵1g/L,Fe2 5mg/L和Ca2 25mg/L.在日处理量100 m3的UASB生物反应器中投加该复合菌群后,木薯酒精废液的COD去除率明显提高,达到90%以上.处理系统运行稳定. 相似文献