全文获取类型
收费全文 | 1229篇 |
免费 | 184篇 |
国内免费 | 540篇 |
专业分类
安全科学 | 207篇 |
废物处理 | 107篇 |
环保管理 | 183篇 |
综合类 | 969篇 |
基础理论 | 96篇 |
污染及防治 | 265篇 |
评价与监测 | 46篇 |
社会与环境 | 28篇 |
灾害及防治 | 52篇 |
出版年
2024年 | 3篇 |
2023年 | 19篇 |
2022年 | 24篇 |
2021年 | 49篇 |
2020年 | 47篇 |
2019年 | 41篇 |
2018年 | 38篇 |
2017年 | 50篇 |
2016年 | 62篇 |
2015年 | 88篇 |
2014年 | 94篇 |
2013年 | 132篇 |
2012年 | 134篇 |
2011年 | 113篇 |
2010年 | 93篇 |
2009年 | 103篇 |
2008年 | 73篇 |
2007年 | 127篇 |
2006年 | 101篇 |
2005年 | 89篇 |
2004年 | 62篇 |
2003年 | 67篇 |
2002年 | 57篇 |
2001年 | 56篇 |
2000年 | 36篇 |
1999年 | 37篇 |
1998年 | 27篇 |
1997年 | 37篇 |
1996年 | 23篇 |
1995年 | 18篇 |
1994年 | 15篇 |
1993年 | 10篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有1953条查询结果,搜索用时 218 毫秒
951.
几种含钙工业废料的固定床吸附除磷特性 总被引:1,自引:1,他引:0
根据钙化合物为有效除磷吸附剂的基础研究结果,将以钙为主要成分的炼铁高炉炉渣(A)、炼钢转炉炉渣(B)和软磁器加工生产中的废料(C)用于二次处理生活污水的除磷.研究结果表明,材料A在合适的pH与钙离子浓度下具有一定的除磷效果,材料C在钙源得到补充的条件下,表现出良好的除磷性能;而材料B由于其组织结构中游离CaO的水解造成机体膨胀,溶出大量钙离子,这种性质恰好可用于补充材料C对钙的需求,取得较好效果,有希望成为一种高效,廉价的除磷吸附剂. 相似文献
952.
IABR-IBAF工艺处理猪场稳定塘废水的实验研究 总被引:1,自引:0,他引:1
难降解有机物含量高且碳氮比失调是造成养猪场稳定塘废水难于处理的主要原因。本文采用基于固定化微生物技术的厌氧折流板(IABR)与曝气生物滤池(IBAF)组合工艺处理稳定塘废水,对比了IABR-IABF组合工艺与单一IBAF工艺的处理效果,研究了碱度和碳源对硝化反硝化过程的影响。组合工艺平均进水COD1532.6mg/L,平均出水为332.7mg/L,去除率为78%,NH3-N平均进水538.6mg/L,平均出水为12.3mg/L,去除率97.7%。以新鲜废水做反硝化阶段的碳源时TN去除率93%,可有效解决脱氮过程中的碳源成本问题。 相似文献
953.
954.
采用大型通用有限元程序,对低硬度大直径橡胶隔震支座在竖向荷载作用下的基本性能进行了精细有限元分析.分析了在竖向荷载作用下支座上下封板、内部钢板的各种应力分布,以及支座顶部是否施加竖向同位移约束、支座孔径比、橡胶材料G值、内部单层橡胶厚度与内部单层钢板厚度之比对支座内钢板受力的影响.结果表明,内部钢板最大Mises应力、... 相似文献
955.
Md. Rayhan Ali Shahin Mahmud Md. Tarikul Islam Md. Nur-E-Alam Md. Tarek Molla Ramisa Binti Mohiuddin Kaisar Ali Talukder Suhaimi Napis Kamal Chowdhury A. K. M. Mohiuddin 《环境质量管理》2023,33(1):473-486
Cities in Bangladesh produce large amounts of solid waste (SW) through various human activities which severely pollutes our native environment. As a result, SW pollutes the three basic environmental elements (air, water, and soil) by increasing pathogenic microbial load, which might be hazardous to public health directly or indirectly. In this study, we conducted 30 samples (i.e., soil, water, and air) collected from areas where municipal solid wastes are dumped (Tangail Sadar Upazila, Bangladesh). All the samples were analyzed to assess bacteriological quality for presumptive viable and coliform count using different agar media. We performed serial dilution 10−3–10−10 times for soil and water samples, and the diluted samples were spread on Mac-Conkey agar and nutrient agar plates. For the air sample, the sterile media containing petri-dish was placed adjacent to the dumpsite of the municipal waste and kept for an hour. Then all the samples were incubated at 37°C overnight for total viable count (TVC) and total coliform count (TCC). Biochemical tests and PCR were performed for the identification of these microorganisms. The antibiogram study was performed to reveal their (identified bacteria) susceptibility against clinically used antibiotics according to the standard disk diffusion technique. The highest bacterial loads were found in the air: TVC 3.273 × 103 and TCC 1.059 × 103 CFU/plate; tube-well water: TVC 8.609 × 103, and TCC 8.317 × 103 CFU/mL; in surface water: TVC 6.24 × 1013 CFU/mL and TCC 2.2 × 1012 CFU/mL; in soil: TVC 2.88 × 1011 and TCC 1.02 × 1011 CFU/g, respectively. Microbes from SW can be transmitted through air, dust particles, or flies, and here we found an average of 1120 microbes spread over 63.61 cm2 area per hour. Eight bacterial isolates (Pseudomonas spp., Klebsiella spp., E. coli, Proteus spp., V. cholera, Salmonella spp., Shigella spp., and Vibrio spp.) were identified by the biochemical test. Among them, E. coli and Shigella spp. were further ensured by PCR targeting bfpA and ipaH genes. Antibiotic susceptibility test results showed that E. coli isolates were highly resistant to erythromycin (80%); Shigella spp. were resistant to nalidixic acid (90%), whereas Salmonella spp. was found resistant to kanamycin (90%). Vibrio spp. were also resistant to azithromycin (80%) and erythromycin (80%), which should be a great concern for us. A semi-structured survey revealed that 63% of respondents suffered from different clinical conditions (intestinal diseases) due to SW pollution. So, steps should be taken to improve the proper management and disposal of solid waste and liquid effluent to save our environment and public health. 相似文献
956.
957.
再生水工艺中曝气生物滤池的特性研究 总被引:1,自引:0,他引:1
对再生水工艺中曝气生物滤池(BAF)的运行特性进行了试验研究,结果表明:BAF对浊度的平均去除率为72%,出水浊度稳定在5NTU以下;COD最佳水力负荷为7 m/h,最佳容积负荷为5.89 kg/(m3.d);NH4+-N最佳水力负荷为5.0 m/h;水力冲击负荷对硝化菌的影响较小,而对异养碳化菌影响较大。 相似文献
958.
959.
介绍电袋组合式除尘器在燃煤电厂240t循环流化床锅炉尾部静电除尘器改造工程中的应用,主要内容包括系统设计、除尘器设计、环保部门的测试结果以及取得的改造效益,并对其结构和技术特点做了进一步的阐述。 相似文献
960.
Linked river basin and coastal water models were applied to analyse the effects of an optimal nitrogen management scenario
in the Oder/Odra river basin on water quality in the Oder (Szczecin) Lagoon and the Pomeranian Bay (Baltic Sea). This scenario
would reduce nitrogen loads into the coastal waters by about 35%, a level which is similar to the load of the late 1960’s.
During summer the primary production and algae biomass in the Oder estuary is limited by nitrogen, which makes a nitrogen
management reasonable. The comparison of the late 1960’s and the mid 1990’s shows that an optimal nitrogen management has
positive effects on coastal water quality and algae biomass. However, this realistic nitrogen reduction scenario would not
ensure a good coastal water quality according to the European Water Framework Directive. A good water quality in the river
will not be sufficient to ensure a good water quality in the lagoon. Nitrogen load reductions bear the risk of increased potentially
toxic, blue-green algae blooms, especially in the Baltic coastal sea. However, to reach water quality improvements in lagoons
and inner coastal waters, nitrogen cuts are necessary. A mere focus on phosphorus is not sufficient. 相似文献