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231.
采用膜生物反应器(MBR)运行16d,未向反应器内活性污泥投加营养物质,对溶解性微生物代谢产物(SMP)、污泥颗粒粒径分布(PSD)、胞外聚合物(EPS)、SMP相对分子量分布(MWDs)进行了定期监测.修正的污染指数(MFI)用来考察与SMP和EPS相关的污泥混合液可滤性.结果表明,MFI值由1.8′104迅速增加到7.3′104s/L2,说明长时间的内源代谢过程对MBR内污泥混合液可滤性有负面的影响.污泥混合液上清液中SMP相对分子量>10kDa的大分子有机物和污泥絮体中1~10μm细小颗粒的增加,将严重恶化污泥混合液的可滤性. 相似文献
232.
233.
The concentrations of bisphenol A (BPA) contained in landfill leachates from solid waste disposal sites were measured. The
concentrations of BPA contained in leachates from industrial waste sites were in the range below the detection limit to 2800 μg/l,
while those from municipal sites were in the range 26–8400 μg/l. The leachates from ash-rich sites contained relatively lower
concentrations of BPA compared with organic-rich leachates. It is suggested that BPA concentration increases with time after
the completion of reclamation in the case of ash-rich sites, whereas the concentration of BPA decreases with time in the case
of organic-rich sites. A 7-year survey on a site in Japan showed neither a decrease nor an increase in the concentration of
BPA during on-going reclamation. A leachate from a site in the Philippines contained high concentrations of BPA. A slight
positive correlation was found between BPA concentrations and total organic carbon (TOC). A major portion of the BPA in leachates
was found in dissolved and organic unassociated fractions, which cannot be precipitated by coagulation. More than 99.9% of
the BPA contained in raw leachates was removed by a conventional series of treatment processes consisting of biological treatment,
coagulation, sedimentation, sand filtration, and activated carbon adsorption.
Received: May 29, 2002 / Accepted: October 17, 2002 相似文献
234.
用离子色谱法(简称IC)测定有害工业固体废物浸出液中的氟化物,其测定方法较化学法(离子选择电极法)手续简便、快速、准确. 相似文献
235.
文章研究了一体式膜生物反应器中环境条件对混合液粘度的影响,以及混合液粘度对膜过滤阻力的影响。试验结果表明:混合液的粘度主要是由胞外聚合物引起的;混合液粘度随着胞外聚合物含量的变化而变化;混合液粘度与各操作条件之间存在一定的关系U=1.586(MESS)^0.614T^-0.106(DO)^0.4697;混合液粘度与膜过滤阻力有较好的相关性。 相似文献
236.
污泥中蛋白质和多糖的分布对脱水性能的影响 总被引:13,自引:6,他引:7
为研究污泥中蛋白质和多糖的组成及空间分布对污泥可脱水性的影响,采用高温(55℃)及pH 10.0和pH 5.5控制条件,进行污泥水解酸化试验;通过离心和超声波法,对污泥中蛋白质和多糖在污泥粘液层、松散附着胞外聚合物层、紧密粘附胞外聚合物层及细胞相层的分布,并对污泥脱水性能(以毛细吸水时间表征)作了跟踪监测.结果表明,污泥中蛋白质和多糖主要分布在细胞相层.在酸性条件下(pH 5.5),污泥高温水解酸化(第0~15 d)使其毛细吸水时间比原污泥稍大,而最终(第20 d)稍低;在碱性条件下(pH 10.0)的污泥水解酸化,则使污泥毛细吸水时间远大于原污泥.统计分析结果表明,污泥脱水性能主要受粘液层的可溶性蛋白质和蛋白质/多糖影响,几乎不受污泥中的蛋白质、多糖和蛋白质/多糖及其它EPS层中的化学组分的影响. 相似文献
237.
基于生物光学模型的二类水体光学活性物质估算:以晋江下游河段为例 总被引:2,自引:1,他引:1
水体中各组分对光谱的吸收和散射构成了水体的固有光学特性,是生物光学模型的重要参数,是建立水质遥感半分析模型的基础.目前该方法多应用于湖泊水质监测,很少用于河流.因此, 本研究以福建晋江下游河段为例, 探讨水面下反射率R(0-)与光学活性物质之间的关系,并建立了光学活性物质的估算模型.结果表明,利用R(0-)753与总悬浮物浓度、R(0-)702/R(0-)680与浮游植物色素浓度、R(0-)670/R(0-)423与CDOM吸收系数分别建立的估算模型能取得理想的效果,其决定系数分别是0.953、 0.820 5和0.621 3,对应的相对误差分别是6.1%、 21.87%和22.18%.三者中以悬浮物浓度的反演精度最高,然后依次为浮游植物色素浓度和CDOM.主要原因在于浮游植物色素的浓度相对较低,光谱信号较弱;CDOM的特征光谱波段很窄,而且该波段内的R(0-)受到其它2种物质存在的影响. 相似文献
238.
239.
Hidemichi Fujii Shunsuke Managi Hiromitsu Kawahara 《Journal of Cleaner Production》2011,19(12):1330-1338
This study analyzes Total Factor Productivity (TFP), which includes all categories of productivity. Our measure investigates productivity in the context of the provision and dissemination of environmental information policies. We investigated data on the emission of toxic chemical substances for the U.S. and Japanese manufacturing firms, including 386 firms for the period 1999-2007 and 466 firms for the period 2001-2008. The results show that productivity improved in all nine industrial sectors and that pollution levels were high in the U.S. and Japan from 2001 to 2007. In particular, the electronics industry improved rapidly after 2002 in both countries, which may be attributed to the enforcement of RoHS and the REACH directive in Europe. As a result of these stringent policies on toxic chemical emissions, the U.S. and Japanese firms, many of which export to the European market, have strong incentives to reduce their toxic chemical emissions. 相似文献
240.
To investigate the effect of ultrasonic pretreatment on anaerobic digestion and sludge dewaterability and further to probe into the
influencing factors on sludge dewaterability, sludge flocs were stratified into four fractions: (1) slime; (2) loosely bound extracellular
polymeric substances (LB-EPS); (3) tightly bound EPS (TB-EPS); and (4) EPS-free pellets. The results showed that ultrasonic
pretreatment increased the anaerobic digestion efficiency by 7%–8%. Anaerobic digestion without ultrasonic pretreatment deteriorated
the sludge dewaterability, with the capillary suction time (CST) increased from 1.42 to 47.3 (sec L)/g-TSS. The application of ultrasonic
pretreatment firstly deteriorated the sludge dewaterability (normalized CST increased to 44.4 (sec L)/g-TSS), while subsequent
anaerobic digestion offset this effect and ultimately decreased the normalized CST to 23.2 (sec L)/g-TSS. The dewaterability of
unsonicated sludge correlated with protein (p = 0.003) and polysaccharide (p = 0.004) concentrations in the slime fraction, while
that of sonicated sludge correlated with protein concentrations in the slime and LB-EPS fractions (p < 0.05). Fluorescent excitationemission
matrix analysis showed that the fluorescence matters in the LB-EPS fraction significantly correlated with sludge dewaterability
during anarobic digestion. 相似文献