首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   89篇
  免费   9篇
  国内免费   33篇
安全科学   20篇
废物处理   10篇
环保管理   9篇
综合类   63篇
基础理论   8篇
污染及防治   10篇
评价与监测   3篇
社会与环境   2篇
灾害及防治   6篇
  2022年   2篇
  2021年   6篇
  2020年   5篇
  2019年   8篇
  2018年   3篇
  2017年   2篇
  2016年   5篇
  2015年   7篇
  2014年   5篇
  2013年   6篇
  2012年   7篇
  2011年   7篇
  2010年   5篇
  2009年   5篇
  2008年   5篇
  2007年   8篇
  2006年   9篇
  2005年   5篇
  2004年   2篇
  2003年   4篇
  2002年   7篇
  2001年   4篇
  2000年   2篇
  1999年   2篇
  1998年   2篇
  1997年   2篇
  1995年   2篇
  1994年   1篇
  1989年   1篇
  1984年   1篇
  1978年   1篇
排序方式: 共有131条查询结果,搜索用时 15 毫秒
91.
在序批式活性污泥(SBR)反应池内投加填料,形成流动床SBR,本试验对SBR和流动床SBR去除COD、TN的效果进行了对比研究,结果表明:流动床SBR对COD、TN的去除效果优于SBR,采用限制性曝气方式时TN的去除率较非限制性曝气方式高。  相似文献   
92.
主要针对好氧移动床处理生活污水挂膜启动方式进行了研究。考察了接种污泥对挂膜启动过程的影响,同时对启动过程中微生物相的变化以及出水中主要污染物随时间的变化情况进行了分析。结果表明:在温度为30~35℃,MBBR1和MBBR2均能在16d左右完成挂膜启动,载体上附着微生物生长稳定时生物膜质量浓度分别达1.2g/L和1.4g/L,接种污泥并不能加速挂膜启动过程。试验还显示,挂膜过程中,CODCr和氨氮的去除率并不是同步提高,好氧异养菌的增殖速度较快,硝化菌的增殖速度较慢。  相似文献   
93.
The main aim of the present work is to discuss the methodological approaches that underpin the “contaminant migrationpopulation effects” models for the evaluation of the detriment to populations of moving organisms in environmental systems with spatial and time dependent pollution levels. A technique to couple the equations controlling the population dynamics and the pollutant dispersion is described and discussed. The domain of application and the limitations of the methodology are analysed and illustrated by some examples. Possible alternative approaches are briefly presented.  相似文献   
94.
通过MBBR工艺和陶粒生物滤池预处理黄河中下游微污染黄河水的对比试验研究,发现陶粒生物滤池和移动床生物膜反应器对CODMn的去除效果接近,但前者对UV254、三氯甲烷前体物和叶绿素a的去除效果均远远高于后者。陶粒生物滤池对氨氮的去除效果略高于移动床生物膜反应器,陶粒生物滤池出水中的亚硝酸盐氮浓度也较低。  相似文献   
95.
李莉  胡玉  曹俊 《化工环保》2019,39(2):142-147
采用移动床生物膜反应器(MBBR)—厌氧移动床生物膜反应器(AMBBR)—MBBR组合工艺处理高氨氮化工废水。反应器采用几何构型优化、比表面积大的新型YD-25生物载体和DNF-203硝化细菌,实现了同步硝化和反硝化,强化了脱氮能力。采用投加菌种和排泥的方式,经27 d的驯化培养即完成了反应器的挂膜启动。试验结果表明:最佳操作条件为HRT 8 d、MBBR中DO 3 mg/L、进水pH 8.0;在进水COD 2 840~7 437 mg/L、ρ(氨氮)92~179 mg/L、TN 148~258 mg/L、pH 6~8的条件下,出水指标均值为COD 352 mg/L、ρ(氨氮)21.2 mg/L、TN 36 mg/L、pH 7.4,满足排放要求。  相似文献   
96.
为了防止在用放射源发生脱落、丢失、超标使用、私自转移等情况,最大限度避免辐射安全事故。有必要设计建立放射源在线监控系统,对放射源放射性指标(辐射剂量率)及所处位置(经纬度)实行连续的自动监测。并通过各级监管平台设置放射源超标、异动等报警程序,全面提升放射源科学监管水平。  相似文献   
97.
This paper develops a process-convolution approach for space-time modelling. With this approach, a dependent process is constructed by convolving a simple, perhaps independent, process. Since the convolution kernel may evolve over space and time, this approach lends itself to specifying models with non-stationary dependence structure. The model is motivated by an application from oceanography: estimation of the mean temperature field in the North Atlantic Ocean as a function of spatial location and time. The large amount of this data poses some difficulties; hence computational considerations weigh heavily in some modelling aspects. A Bayesian approach is taken here which relies on Markov chain Monte Carlo for exploring the posterior distribution.  相似文献   
98.
移动床生物膜反应器载体亲水改性的试验研究   总被引:1,自引:1,他引:0  
张雪辉  周律  朱天乐 《环境科学》2007,28(2):368-370
采用聚合物共混法研究载体亲水性改善的可行性,在此基础上研究电晕处理对亲水性能强化的效果和持续性.结果表明,共混方式能够改善载体亲水性能,接触角从108°降至88°,载体表面已经呈亲水性;电晕处理能够强化亲水性能,接触角可进一步降低至72°,但强化效果持续时间短.从检测指标和检测方法2方面建立载体生物学性能评价体系,研究亲水性能改善对载体生物学性能的影响.对比电晕处理前后载体,经20 d生物学性能试验检测表明,亲水性能经电晕处理强化的载体启动快,启动第2 d COD和NH+4-N去除率就分别高达80%和97%,同期未电晕处理载体仅为61%和63%;后期两者处理效果基本持平,说明电晕改性初期效果明显,而持续时间有限;也表明所建立的生物学性能评价体系快速可靠.  相似文献   
99.
In the paper concepts for wastewater treatment of the future are discussed by the use of a) one flow diagram based on established, compact, proven technologies (i.e. nitrification/denitrification for N-removal in the mainstream) and b) one flow diagram based on emerging, compact technologies (i.e. de-ammonification in the main stream).The latter (b) will give an energy-neutral wastewater treatment plant, while this cannot be guaranteed for the first one (a). The example flow diagrams show plant concepts that a) minimize energy consumption by using compact biological and physical/chemical processes combined in an optimal way, for instance by using moving bed biofilm reactor (MBBR) processes for biodegradation and high-rate particle separation processes, and de-ammonification processes for N-removal and b)maximize energy (biogas) production through digestion by using wastewater treatment processes that minimize biodegradation of the sludge (prior to digestion) and pretreatment of the sludge prior to digestion by thermal hydrolysis. The treatment plant of the future should produce a water quality (for instance bathing water quality) that is sufficient for reuse of some kind (toilet flushing, urban use, irrigation etc.). The paper outlines compact water reclamation processes based on ozonation in combination with coagulation as pretreatment before ceramic membrane filtration. In the paper concepts for domestic wastewater treatment plants of the future are discussed by the use of a) one flow diagram based on established, compact, proven technologies (i.e. nitrification/denitrification for N-removal in the mainstream) and b) one flow diagram based on emerging, compact technologies (i.e. de-ammonification in the main stream).The latter (b) will give an energy-neutral wastewater treatment plant, while this cannot be guaranteed for the first one (a). The example flow diagrams show plant concepts that a) minimize energy consumption by using compact biological and physical/chemical processes combined in an optimal way, for instance by using moving bed biofilm reactor (MBBR) processes for biodegradation and high-rate particle separation processes, and de-ammonification processes for N-removal and b)maximize energy (biogas) production through digestion by using wastewater treatment processes that minimize biodegradation of the sludge (prior to digestion) and pretreatment of the sludge prior to digestion by thermal hydrolysis. The treatment plant of the future should produce a water quality (for instance bathing water quality) that is sufficient for reuse of some kind (toilet flushing, urban use, irrigation etc.). The paper outlines compact water reclamation processes based on ozonation in combination with coagulation as pretreatment before ceramic membrane filtration.  相似文献   
100.
Three laboratory-scale moving bed biofilm reactors (MBBR) with different carrier filling ratios ranging from 40% to 60% were used to study the effects of carrier-attached biofilm on oxygen transfer efficiency. In this study, we evaluated the performance of three MBBRs in degrading chemical oxygen demand and ammonia. The three reactors removed more than 95% of NH 4 + -N at an air flow-rate of 60 L·h–1. The standard oxygen transfer efficiency (αSOTE) of the three reactors was also investigated at air flow-rates ranging from 60 to 100 L·h–1. These results were compared to αSOTE of wastewater with a clean carrier (no biofilm attached). Results showed that under these process conditions, αSOTE decreased by approximately 70% as compared to αSOTE of wastewater at a different carrier-filling ratio. This indicated that the biofilm attached to the carrier had a negative effect on αSOTE. Mechanism analysis showed that the main inhibiting effects were related to biofilm flocculants and soluble microbial product (SMP). Biofilm flocs could decrease αSOTE by about 20%, and SMP could decrease αSOTE by 30%–50%.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号