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531.
厦门市机动车排气污染现状与防治对策   总被引:2,自引:0,他引:2  
方丽花 《交通环保》2005,26(2):47-48
分析了厦门市机动车排气污染的现状及原因,从政策、技术、交通管理等方面入手,结合工作实际,提出了完善监督机制和推行机动车环保分类标志制度等一系列具体的防治对策。  相似文献   
532.
上海市环境空气NO2浓度时空分布特征   总被引:3,自引:0,他引:3  
为监测机动车尾气造成的氧化型光化学烟雾的污染,采用被动扩散管的监测方法在上海布设65个监测点位,经13个月的连续监测,得出了上海市环境空气中NO2浓度时空分布特征及污染的重点区域,NO2时空分布主要特征:NO2高浓度值出现在交通主干道上(高架出口、隧道口、车辆堵塞的交通要道);NO2浓度空间分布呈市中心区→市郊区→外围农村区逐渐减弱的趋势;总体时序分布呈秋冬季高于春夏季的变化趋势。  相似文献   
533.
尤隽  王晔 《环境科技》2007,20(6):68-71
由于汽车工业的迅速发展和能源的日益紧张,既经济又环保的汽车必将得到青睐.贫燃发动机可能成为一种选择,但是如何去除贫燃条件下产生的大量氮氧化物,就成为汽车尾气催化剂研究的新热点.在此主要分析了目前的一些最新研究成果,并对其发展趋势进行了展望.  相似文献   
534.
曾胜学  张立奎 《环境工程》2012,(Z2):209-213
推导出了重、柴油发电机烟气余热回收在几种典型情况下的传热算式,并举例说明其应用。  相似文献   
535.
利用FDS模拟研究走廊中排烟口数量、位置以及挡烟垂壁与缓冲区的结合对高层建筑烟气控制效果的影响,寻找最佳组合烟气控制模式。结果表明,在走廊中部设置1个以排除火灾产生烟气为主的排烟口,在空气幕前方2m处设置1个以排除新鲜空气为主的排气口,并且在排气口后方0.5m处设置1个挡烟垂壁的组合烟气控制模式具有最佳的烟气控制效果。挡烟垂壁离机械排烟口0.5m时,可以有效降低缓冲区及前室的温度和烟气浓度,前室内CO2体积分数下降21.4%,温度下降9℃。当挡烟垂壁离空气幕较近时,走廊内的温度和烟气浓度反而上升。  相似文献   
536.
在分析地铁车站火灾烟控和乘客疏散要求的基础上,分析了地铁防排烟设计的基本思路和模式,结合某多层结构地下车站,给出了通风排烟系统的设计方案。利用模拟仿真的方法对通风排烟系统火灾事故情况下的运行效果进行了验证评估。计算表明,隧道烟控流速、楼扶梯开口流速、可用安全疏散时间等指标均可达到规范的要求。提出的设计方案和事故运行模式可提供作为一种地下车站通风排烟系统设计的模式。  相似文献   
537.
Phenol removal by n/m Fe in the presence of H2O2 was highly effective. Increasing the amounts of n/m Fe and H2O2?increased the phenol removal rate. Phenol removal was decreased with an increase in the concentration of phenol. The natural pH (6.9) of the solution was highly effective for phenol removal. The pseudo-first-order kinetics was best fitted for the degradation of phenol. The study investigates the magnetic separation of Fe from automobile shredder residue (ASR) (<0.25 mm) and its application for phenol degradation in water. The magnetically separated Fe was subjected to an ultrasonically assisted acid treatment, and the degradation of phenol in an aqueous solution using nano/micro-size Fe (n/m Fe) was investigated in an effort to evaluate the possibility of utilizing n/m Fe to remove phenol from wastewater. The prepared n/m Fe was analyzed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The effects of the dosages of n/mFe, pH, concentration of phenol and amount of H2O2 on phenol removal were evaluated. The results confirm that the phenol degradation rate was improved with an increase in the dosages of n/mFe and H2O2; however, the rate is reduced when the phenol concentration is higher. The degradation of phenol by n/mFe followed the pseudo-first-order kinetics. The value of the reaction rate constant (k) was increased as the amounts of n/m Fe and H2O2 increased. Conversely, the value of k was reduced when the concentration of phenol was increased. The probable mechanism behind the degradation of phenol by n/m Fe is the oxidation of phenol through hydroxyl radicals which are produced during the reaction between H2O2 and n/m Fe.  相似文献   
538.
介绍了MTBE汽油添加剂净化汽车尾气的作用,分析污染地下水源和遭到禁用的原因,提出建议.  相似文献   
539.
循环冷却水系统的浓缩倍数Ⅳ是一个重要参数。探讨了浓缩倍数与补充水量、排污量以及循环利用率的关系,并说明了控制浓缩倍数的重要性。  相似文献   
540.
Polynuclear aromatic compounds (PAC) were characterized in diesel fuel, kerosene fuel and unmodified sunflower oil as well as in their respective engine exhaust particulates. Diesel fuel was found to contain high amounts of different PAC, up to a total concentration of 14,740?ppm, including carbazole and dibenzothiophene, which are known carcinogens. Kerosene fuel was also found to contain high amounts of different PAC, up to a total concentration of 10,930?ppm, consisting mainly of lower molecular weight (MW) naphthalene and its alkyl derivatives, but no PAC component peaks were detected in the unmodified sunflower oil. Engine exhaust particulates sampled from a modified one-cylinder diesel engine running on diesel, kerosene and unmodified sunflower oil, respectively, were found to contain significantly high concentrations of different PAC, including many of the carcinogenic ones, in the soluble organic fraction (SOF). PAC concentrations detected at the exhaust outlet indicated that most of the PAC that were present in diesel and kerosene fuels before the test runs got completely burnt out during combustion in the engine whereas some new ones were also formed. The difference between the character and composition of PAC present in the fuels and those emitted in the exhaust particulates indicated that exhaust PAC were predominantly combustion generated. High amounts of PAC, up to totals of 52,900 and 4830?µg?m?3 of burnt fuel, in diesel and kerosene exhaust particulates, respectively, were detected in the dilution tunnel when the exhaust emissions were mixed with atmospheric air. Significant amounts of PAC were also emitted when the engine was run on unmodified sunflower oil with a total concentration of 17,070?µg?m?3 of burnt fuel detected in the dilution tunnel. High proportions of the combustion-generated PAC determined when the engine was run on diesel, kerosene and unmodified sunflower, respectively, consisted of nitrogen-containing PAC (PANH) and sulphur-containing PAC (PASH).  相似文献   
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