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331.
The effect of oxygen-enriched air during fluidized bed co-gasification of a mixture of coal, plastics and wood has been investigated. The main components of the obtained syngas were measured by means of on-line analyzers and a gas chromatograph while those of the condensate phase were off-line analysed by means of a gas chromatography-mass spectrometer (GC-MS). The characterization of condensate phase as well as that of the water used as scrubbing medium completed the performed diagnostics. The experimental results were further elaborated in order to provide material and substances flow analyses inside the plant boundaries. These analyses allowed to obtain the main substance distribution between solid, gaseous and condensate phases and to estimate the conversion efficiency of carbon and hydrogen but also to easily visualise the waste streams produced by the process. The process performance was then evaluated on the basis of parameters related to the conversion efficiency of fuels into valuable products (i.e. by considering tar and particulate as process losses) as well as those related to the energy recovery.  相似文献   
332.
文章研究了C/N对悬浮填料生物反应器脱氮效果的影响。出水中NH4+-N、NO2--N和NO3--N浓度以及pH值变化均受C/N的影响,实验得到的最佳C/N质量比为12∶1,TN去除率平均在85%。  相似文献   
333.
针对河北省某厂的燃煤锅炉的烟管腐蚀问题,通过水质分析、采集腐蚀处的产物,进行XRD、扫描电镜、能谱分析等手段分析腐蚀产生原因和腐蚀速率的影响因素.发现烟管与水接触侧发生了氧腐蚀.水垢附着速率、溶解氧含量这两种因素对腐蚀速率影响较大.并针对锅炉材质、锅炉设计、水质处理、停炉保养、人员素质等方面提出改进措施,为今后处理类似问题提供经验和参考.  相似文献   
334.
Solid fuels in chemical-looping combustion   总被引:1,自引:0,他引:1  
The feasibility of using a number of different solid fuels in chemical-looping combustion (CLC) has been investigated. A laboratory fluidized bed reactor system for solid fuel, simulating a chemical-looping combustion system by exposing the sample to alternating reducing and oxidizing conditions, was used. In each reducing phase 0.2 g of fuel in the size range 180–250 μm was added to the reactor containing 40 g oxygen carrier of size 125–180 μm. Two different oxygen carriers were tested, a synthetic particle of 60% active material of Fe2O3 and 40% MgAl2O4 and a particle consisting of the natural mineral ilmenite. Effect of steam content in the fluidizing gas of the reactor was investigated as well as effect of temperature. A number of experiments were also made to investigate the rate of conversion of the different fuels in a CLC system. A high dependency on steam content in the fluidizing gas as well as temperature was shown. The fraction of volatiles in the fuel was also found to be important. Furthermore the presence of an oxygen carrier was shown to enhance the conversion rate of the intermediate gasification reaction. At 950 °C and with 50% steam the time needed to achieve 95% conversion of fuel particles with a diameter of 0.125–0.18 mm ranged between 4 and 15 min depending on the fuel, while 80% conversion was reached within 2–10 min. In almost all cases the synthetic Fe2O3 particle with 40% MgAl2O4 and the mineral ilmenite showed similar results with the different fuels.  相似文献   
335.
流化式生物膜法处理含酚废水的效能   总被引:7,自引:2,他引:7  
通过动态试验,对自制载体的流化式生物膜法处理含酚废水的效能进行了重点考察,结果表明,当COD容积负荷达4.0kg/(m^3.d)时,COD的去除率平均在80%以上,酚去除率在90-100%之间,出水COD和酚可达到排放标准。自制的载体挂膜快,膜厚适宜,易于流化,本处理系统抗冲击负荷能力强,具有较高的脱氢酶活怀。  相似文献   
336.
介绍了填埋场垃圾稳定化机理,分析了影响填埋场稳定化的因素,提出了建立准好氧填埋场不仅有利于加快垃圾的稳定化进程,还可减排温室气体和改善渗滤液水质,确保填埋场地最大限度地安全再利用。  相似文献   
337.
钙钛矿型SrFeO_(3-λ)催化降解水溶性染料   总被引:6,自引:0,他引:6  
采用柠檬酸络合法合成了钙钛矿型 Sr Fe O3-λ复合氧化物 ,以其为催化剂对不同水溶性染料溶液进行降解脱色试验 ,各种染料的脱色率均较高 ,表明 Sr Fe O3-λ具有很好的催化活性 ,这主要与 Sr Fe O3-λ中 Fe离子的变价和存在大量氧空位有关。  相似文献   
338.
The chemistry and flow of water in the abandoned Tomitaka mine of Miyazaki, western Japan were investigated. This mine is located in a non-ferrous metal deposit and acid mine drainage issues from it. The study was undertaken to estimate the quantities of mine drainage that needs to be treated in order to avoid acidification of local rivers, taking into account seasonal variations in rainfall. Numerical models aimed to reproduce observed water levels and fluxes and chemical variations of groundwater and mine drainage. Rock–water interactions that may explain the observed variations in water chemistry are proposed. The results show that: (1) rain water infiltrates into the deeper bedrock through a highly permeable zone formed largely by stopes that are partially filled with spoil from excavations (ore minerals and host rocks); (2) the water becomes acidic (pH from 3 to 4) as dissolved oxygen oxidizes pyrite; (3) along the flow path through the rocks, the redox potential of the water becomes reducing, such that pyrite becomes stable and pH of the mine drainage becomes neutral; and (4) upon leaving the mine, the drainage becomes acidic again due to oxidation of pyrite in the rocks. The present numerical model with considering of the geochemical characteristics can simulate the main variations in groundwater flow and water levels in and around the Tomitaka mine, and apply to the future treatment of the mine drainage.  相似文献   
339.
为实现室温下长期储存的厌氧氨氧化污泥的活性快速恢复,采用3组反应器分别对在室温(15~30℃)且无基质的条件下储存9个月的厌氧氨氧化污泥进行活性恢复,其中R2和R3反应器分别添加彗星纤维填料和K3填料作为生物载体,探究不同填料添加对厌氧氨氧化污泥活性恢复速率的影响.结果表明,R2和R3反应器分别在第8 d和第10 d开...  相似文献   
340.
对舰船装备进行冲击试验的目的是检验战时环境下装备承受核武器和常规武器产生的冲击载荷的能力。论述了冲击环境效应,舰船装备的抗冲击级别、安装类别、冲击试验类型、安装部位分类、冲击试验设备与试验、冲击试验用安装架、抗冲击设计和安装等要求。  相似文献   
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