全文获取类型
收费全文 | 455篇 |
免费 | 82篇 |
国内免费 | 277篇 |
专业分类
安全科学 | 57篇 |
废物处理 | 68篇 |
环保管理 | 47篇 |
综合类 | 349篇 |
基础理论 | 97篇 |
污染及防治 | 165篇 |
评价与监测 | 24篇 |
社会与环境 | 4篇 |
灾害及防治 | 3篇 |
出版年
2024年 | 1篇 |
2023年 | 6篇 |
2022年 | 15篇 |
2021年 | 24篇 |
2020年 | 31篇 |
2019年 | 35篇 |
2018年 | 25篇 |
2017年 | 40篇 |
2016年 | 50篇 |
2015年 | 37篇 |
2014年 | 40篇 |
2013年 | 62篇 |
2012年 | 57篇 |
2011年 | 48篇 |
2010年 | 37篇 |
2009年 | 49篇 |
2008年 | 30篇 |
2007年 | 40篇 |
2006年 | 40篇 |
2005年 | 14篇 |
2004年 | 13篇 |
2003年 | 15篇 |
2002年 | 16篇 |
2001年 | 15篇 |
2000年 | 17篇 |
1999年 | 11篇 |
1998年 | 8篇 |
1997年 | 7篇 |
1996年 | 3篇 |
1995年 | 9篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1989年 | 3篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有814条查询结果,搜索用时 31 毫秒
701.
以ACOF和陶粒作为生物滤床的填料,利用P.putida净化气相中的氯苯,并将十二烷基磺酸钠(SDS)添加于生物滴滤床的喷淋液中,研究其对滤床处理氯苯废气效果的影响.微生物静态培养结果表明,当培养基中SDS浓度大于35 mg/L时,对P.putida存在明显抑制作用.在喷淋液中添加25 mg/L的SDS,有助于缩短滤床的适应期,并提高稳态下滤床的性能.对于填料为ACOF的情况,喷淋液中的SDS最优添加浓度为25 mg/L,此时滤床的最大去除负荷为234.7 g/(m3·h).喷淋液中的SDS经过5 d的运行,会有18%~20%的损失,但对滤床的性能没有明显影响. 相似文献
702.
研究了化学沉淀法和氨基膦酸型螯合树脂吸附法对催化裂化钠碱脱硫液中Ca~(2+)和Mg~(2+)的去除效果。实验结果表明:NaOH沉淀法可有效去除钠碱脱硫液中的Mg~(2+),当溶液pH为12、反应时间为15 min时,Mg~(2+)去除率达91.6%;NaOH-Na_2CO_3联合沉淀法无法去除钠碱脱硫液中的Ca~(2+);经过NaOH溶液有效除Mg~(2+)后的脱硫液再采用氨基膦酸型螯合树脂吸附柱去除其中的Ca~(2+)和Mg~(2+),可使出水硬度小于2 mg/L。提高进水pH、降低进水流量、降低进水硬度均可提高单位体积树脂的处理水量。 相似文献
703.
704.
利用植物根尖细胞微核技术,研究不同质量浓度的亚砷酸钠(0.3mg/L,1.0mg/L,3.0mg/L,10.0mg/L,30.0mg/L)对蚕豆和洋葱根尖细胞的遗传损伤效应。研究结果表明,用亚砷酸钠处理12h后,可诱发蚕豆(亚砷酸钠质量浓度0.3—30.0mg/L)和洋葱(亚砷酸钠质量浓度1.0—30.0mg/L)根尖细胞遗传损伤,使根尖细胞微核率增加、分裂指数下降。在一定处理浓度范围内(蚕豆的为0—3.0mg/L;洋葱为0—10.0mg/L),细胞微核率与处理浓度呈正相关(P〈0.01);分裂指数与处理浓度呈负相关(P〈0.01)。研究表明,亚砷酸钠能引起植物细胞遗传物质损伤,因此,可利用蚕豆和洋葱根尖细胞微核技术检测环境中的砷污染。 相似文献
705.
微乳液中2,4—二硝基氯苯水解反应的研究 总被引:3,自引:0,他引:3
研究了2,4-硝基氯苯在十二烷基磺酸钠/油/醇/水组成的O/W型微乳液中的水解反应。考察了烃,醇与表面活性剂的种类及用量,OH^-浓度和温度等对O/W型微乳液中2,4-二硝基氯苯水解反应的影响。 相似文献
706.
研究了在HAC-NaAC介质中,痕量铬(VI)催化过氧化氢氧化罗丹明6G的褪色反应及其动力学条件,建立了催化荧光测定痕量铬(VI)的新方法。催化反应在沸水浴中进行15min,为假零级反应。方法的检出限为2.1×10-9g/mL,线性范围为0.2~2.5μg/25mL。将该法用于环境水样中痕量铬(VI)的测定,结果良好。 相似文献
707.
708.
Gölcük Nature Park (GNP) is an area protected by law in Turkey. It is an important nature park with rich flora, fauna, geomorphologic forms, landscape features, and recreational potential in the region. However, GNP does not have a recreation management plan. The purpose of this study was to determine the actual natural, cultural, and visual resources of GNP, determine the most suitable recreational sites with multiple factors, evaluate the demands and tendencies of visitors, and suggest recreational activities and facilities for the most suitable sites of GNP. However, it was also conceived as leading to a recreational plan and design of GNP in the future and identifying the entire appropriate and current data of GNP with the creation of various maps. This study used multifactor analysis to determine the most suitable recreation sites of GNP. Used recreation factors were established including degree of slope, proximity to water resources, accessibility, elevation, vegetation, soil, climate, aspect, current cultural facilities, visual values, and some limiting factors in accordance with the characteristics of GNP. Weighting and suitability values of factors were determined by 30 local expert surveys. All obtained data were evaluated and integrated in the Geographical Information Systems base. Obtained maps were overlapped. Thus, recreational suitability zones map were created manually. However, the demands and behaviours from visitor surveys in GNP were focused on the most suitable recreation sites of the park. Finally, 10% of GNP was identified as the most suitable sites for recreational use. Various recreational facilities and activities (including picnicking, sports facilities and playgrounds, camping sites, walking paths, food and local outlets, etc.) were recommended for nine of the most suitable areas on the proposed recreational map. 相似文献
709.
在16.2L厌氧折流板反应器(ABR)中,以五氯酚钠配水进行了毒物冲击负荷试验当进水COD为1100~1200mg/L,HRT为24h时,连续两大投加五氯酚钠 17.72、17.48mg/L,再以 1~2mg/L连续进水结果表明,ABR具有较强的抗毒物冲击自助,反应器后段 COD去除率在第6d可基本恢复到冲击前水平,整个系统活性恢复约需4周仲击负荷后系统微生物依次经历明显被抑制的阶段及其代谢活性恢复的阶段用COD去除率比值和CODvfa与CODfilt值可以表征系统恢复的历程 相似文献
710.
A new process for removing the pollutants in aqueous solution-activated alumina bed in pulsed high-voltage electric field was investigated for the removal of phenol under different conditions. The experimental results indicated the increase in removal rate with increasing applied voltage, increasing pH value of the solution, aeration, and adding Fe^2+. The removal rate of phenol could reach 72.1% when air aeration flow rate was 1200 ml/min, and 88.2% when 0.05 mmol/L Fe^2+ was added into the solution under the conditions of applied voltage 25 kV, initial phenol concentration of 5 mg/L, and initial pH value 5.5. The addition of sodium carbonate reduced the phenol removal rate. In the pulsed high-voltage electric field, local discharge occurred at the surface of activated alumina, which promoted phenol degradation in the thin water film. At the same time, the space-time distribution of gas-liquid phases was more uniform and the contact areas of the activated species generated from the discharge and the pollutant molecules were much wider due to the effect of the activated alumina bed. The synthetical effects of the pulsed high-voltage electric field and the activated alumina particles accelerated phenol degradation. 相似文献