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841.
Gomti river receives industrial as well as domestic wastes from various drains of Lucknow city. In the process the water and sediment of the river Gomti get contaminated with heavy metals and other pollutants. In the present study, impacts of domestic/industrial wastes on the water and sediment chemistry of river Gomti with special reference to heavy metals have been investigated in different seasons (summer, winter and rainy). For this, seven sampling sites: Gaughat, Mohan Meakin, Martyrs Memorial, Hanuman Setu, Nishatganj bridge, Pipraghat and Malhaur, in the river Gomti in Lucknow region were identified and samples of water and sediments were collected in all the three seasons. In the collected water and sediment samples, six metals (Cd, Cr, Cu, Ni, Pb, and Zn) were analyzed on ICP-AES (Inductively coupled plasma emission spectroscopy) Labtam Plasmalab 8440. High concentrations of all the metals were noticed in water and sediment in rainy season compared to summer and winter. Because in rainy season runoff from open contaminated sites, agricultural field and industries, directly comes into the river without any treatment. In both the cases, the concentration of zinc was maximum (0.091 g/ml in water and 182.13 g/g in sediment) and the concentration of cadmium (0.001 g/ml in water and 17.26 g/g in sediment) was minimum. Higher concentration of metal in water and sediment during rainy season could be due to the industrial/agricultural/domestic runoff coming into the river.  相似文献   
842.
Dermal exposure to pesticides is one of the main sanitaryproblems which greenhouses workers face. With the dual aimsof establishing both the body part that receives the greatestexposure and the variable that has greatest influence on this exposure level, 22 pesticide application trials were performed. Trials were carried out in different greenhouse vegetable crops,using different pesticides and different spray diameters from the spray gun. In order to determine dermal exposure, the wholebody method was used. Pieces of the applicator suit were subject to an extraction procedure and their pesticide contentdetermined using GC-NPD analysis. Multivariate analysis were applied to the data obtained. Principal component analysis showed that all trials produced a high exposure level on lowerleft leg and lower right leg. Cluster analysis distinguished between three sample groups. The most and the least affectedparts were clearly distinguished. Discriminant analysis indicated that the thin drop size of the spray gun is responsible for both the differences between groups and the minimum or maximum exposure level measured on the applicatorsuit. Therefore, selecting the variables, lower legs and thindrop size, is considered fundamental in designing programs formonitoring pesticide exposure.  相似文献   
843.
为研究大型机加车间噪声减噪工程现状效果和特点,选取某大型机加车间数控机床为研究对象,对其进行减噪工程治理,现场实测了治理前和治理后的噪声数据,并对噪声测量结果进行分析。研究结果表明:数控机床操作人员8 h连续等效A声级从治理前的89.2 dB(A),降到治理后的74.3 dB(A),降低了16.7%.;数控机床操作岗位位置测点,在加工1个机件的测量时间段里,噪声值从治理前的85.9 dB(A),降到治理后的55.1 dB(A),降低了33.85%;对机加车间现场布置了67个测点,在加工1个机件的测量时间段里进行测量,得到该车间噪声治理前和治理后噪声分布图;对数控机床减噪工程治理前和治理后的频谱进行了分析,得出治理前和治理后各自的最大声级所在频段不随距离的改变而改变,高频减噪效果显著。  相似文献   
844.
The aim of the study was to determine the cardiovascular response to continuous (4 °C for 60 min) and intermittent (10 min at 4?°C and 10 min at room temperature alternately) exposure to the cold in 30 healthy young men. The subjects were equipped with a set of identical clothing (insulation 2.1 clo) and during the stay in the chamber and outside performed the same activities, i.e., walking on a treadmill at a speed of 0.5?km/h. The tests included assessing the central circulatory system using the Holter system and assessing the peripheral circulatory system using impedance plethysmography and Doppler ultrasound. The analysis of the parameters that describe the central and peripheral circulation poses a difficulty in determining which variant of exposure constitutes a greater load on the circulatory system. It should be noted that even the conditions used in the study may cause adverse effects in the cardiovascular system.  相似文献   
845.
Objective: The purpose of this study was to describe the nature and extent of current powered 2-wheeler (PTW) risk exposures in order to support future efforts to improve safety for this mode of transport.

Methods: A cross-sectional analysis of the control arm of a population-based case-control study was conducted. The control sample was selected from 204 sites on public roads within 150 km of the city of Melbourne that were locations of recent serious injury motorcycle crashes. Traffic observations and measurements at each site were sampled for a mean of 2 h on the same type of day (weekday, Saturday, or Sunday) and within 1 h of the crash time. Photographs of passing riders during this observation period recorded data relating to characteristics of PTWs, age of riders, travel speed of PTWs and all vehicles, time gaps between vehicles, visibility, and protective clothing use.

Results: Motorcycles and scooters represented 0.6% of all traffic (compared with 4% of all vehicle registrations). Riders were significantly more likely to have larger time gaps in front and behind when compared to other vehicles. The average travel speed of motorcycles was not significantly different than the traffic, but a significantly greater proportion were exceeding the speed limit when compared to other vehicles (6 vs. 3%, respectively). The age of registered owners of passing motorcycles was 42 years. Over half of riders were wearing dark clothing with no fluorescent or reflective surfaces. One third of motorcyclists had maximum coverage of motorcycle-specific protective clothing.

Conclusions: A very low prevalence of motorcyclists combined with relatively higher rates of larger time gaps to other vehicles around motorcycles may help explain their overrepresentation in injury crashes where another vehicle fails to give way. An increased risk of injury in the event of a crash exists for a small but greater proportion of motorcyclists (compared to other vehicle types) who were exceeding the speed limit. An apparent shift toward older age of the active rider population may be reducing injury crash risk relative to exposure time. There is significant scope to improve the physical conspicuity of motorcyclists and the frequency of motorcycle specific protective clothing use. These results can be used to inform policy development and monitor progress of current and future road safety initiatives.  相似文献   

846.
铅吸附深色有隔内生真菌的筛选及其吸附特性   总被引:1,自引:0,他引:1  
本文通过测定沙门外瓶柄霉(Exophiala salmonis BC5)、甘瓶霉(Phialophora mustea BC42)、菊异茎点霉(Paraphoma chrysanthemicola B100)和枝状枝孢菌(Cladosporium cladosporioides B142)4种具有耐铅特性的深色有隔内生真菌(Dark Septate Endophytes,DSE)非活性菌丝的铅吸附能力,从中筛选出铅吸附能力强的菌种并研究其吸附特性.扫描电镜观察结果显示,4种DSE吸附剂均有管道状结构,以枝状枝孢菌的直径最大((4.04±0.68)μm),且较为完整,枝状枝孢菌吸附剂的表面比较粗糙,其余3种DSE吸附剂的表面均比较光滑;傅立叶红外光谱分析表明,4种DSE吸附剂均含有氨基(—NH2)、羟基(—OH)、酯羰基(—COO)和羧基(—COOH)等官能团;当吸附时间分别为15 min和60 min时,枝状枝孢菌对铅的去除率、吸附量分别达83.30%、14.73 mg·g~(-1)和94.86%、19.54 mg·g~(-1),均显著高于其他3种真菌,其次是菊异茎点霉,沙门外瓶柄霉和甘瓶霉的吸附能力较差.进一步研究枝状枝孢菌的铅吸附特性,结果表明:p H(2.0~6.0)、初始金属浓度(10~300μg·m L~(-1))、吸附时间(5~180 min)、吸附剂剂量(0.5~10 g·L~(-1))、温度(20~40℃)及转速(80~180 r·min-1)对枝状枝孢菌的铅吸附过程均有显著影响,最佳的吸附条件分别为p H 5.0、初始金属浓度150μg·m L~(-1)、吸附时间120 min、吸附剂剂量3 g·L~(-1)、温度25℃、转速180 r·min-1,此时吸附量为40.8 mg·g~(-1).  相似文献   
847.
中国工业过程大气铅排放特征   总被引:2,自引:1,他引:1  
依据典型行业活动水平数据和排放因子,采用"自下而上"排放因子法构建了2000—2010年我国有色金属冶炼、钢铁冶炼、建筑材料生产和铅酸电池生产等工业生产过程大气铅(Pb)排放清单.结果显示,我国工业过程大气Pb排放呈逐年递增趋势,年均增长率为12.5%,2010年排放量高达14920.47t;有色金属冶炼过程为大气Pb的主要来源,比重高达66.7%,其中,铅冶炼过程对整个工业过程的Pb排放贡献达到29.0%.钢铁烧结过程大气Pb排放仅次于有色金属冶炼过程,排放贡献率达23.1%,其排放主要来源于粗钢冶炼.另外,由于产业集中度低和控制技术相对落后,导致建材生产行业和铅酸电池生产过程排放对周边的环境影响也不容忽视.受矿产资源分布不均及产业布局等因素影响,我国工业过程大气Pb排放地区分布差异明显,主要集中在湖南、河南、云南、河北和江西等省份.  相似文献   
848.
晏彪  马萍  吴卓  杨旭  武阳 《环境科学学报》2016,36(8):3095-3102
作为"绿色换代产品",邻苯二甲酸二异壬酯(DINP)在全球范围逐渐取代邻苯二甲酸二(2-乙基己)酯(DEHP)成为聚氯乙烯制品的主要增塑剂.但人体DINP暴露也可能存在健康隐患,故近年来受到越来越多环境科学领域专家的关注.为了探讨DINP皮肤暴露是否对机体有氧化损伤的作用,本研究以Balb/c小鼠为模式生物进行实验,42只雄性Balb/c小鼠随机被分为5个DINP染毒组(0.02、0.2、2、20、200 mg·kg-1)和1个溶剂对照组,每组7只.皮肤染毒28 d后,用所获得的肝和肾组织匀浆测定活性氧自由基(ROS)、丙二醛(MDA)、还原型谷胱甘肽(GSH),用所获得的肝和肾细胞测定DNA-蛋白质交联(DPC)系数,同时观察小鼠背部皮肤的形态变化情况.实验结果表明,随着DINP染毒剂量的升高,脏器系数、ROS和MDA含量及DPC系数逐渐上升,GSH含量逐渐降低,各指标均呈现出一定的剂量-反应关系(p0.05,p0.01).研究表明,较高剂量的DINP(≥20 mg·kg-1)亦可通过皮肤暴露的方式造成小鼠肝脏和肾脏组织细胞的氧化损伤.  相似文献   
849.
舰船设备振动试验方法的探讨   总被引:2,自引:2,他引:0  
目的探讨舰船设备振动试验中的几个问题并提出解决方法。方法分析GJB 150.16A,GJB4.7—83和MIL-STD-167-1A等振动试验标准,找出其中存在的缺点。阐述实验室模拟与实际环境的差异,提出改进建议。结果 GJB 150.16A中没有明确说明随机部分和正弦部分是单独试验还是叠加试验,GJB 4.7—83和MIL-STD-167-1A中没有给出随机振动的条件,只有正弦振动部分。结论对于标准中存在的缺点,在每个轴向,首先进行一半的功能试验,再进行随机叠加正弦/随机振动,最后进行另一半功能试验。对于实验室模拟与实际环境存在差异的问题,通过采用力谱控制、采用模拟舰船结构的夹具、规定安装方式、对环境条件进行反复迭代等方法改进。  相似文献   
850.
The fluorescent lamp recycling sector is growing considerably in Europe due to increasingly strict regulations aimed at inciting the consumption of low energy light bulbs and their end-of-life management. Chemical risks were assessed in fluorescent lamp recycling facilities by field measurement surveys in France, highlighting that occupational exposure and pollutant levels in the working environment were correlated with the main recycling steps and processes.The mean levels of worker exposure are 4.4 mg/m3, 15.4 μg/m3, 14.0 μg/m3, 247.6 μg/m3, respectively, for total inhalable dust, mercury, lead and yttrium. The mean levels of airborne pollutants are 3.1 mg/m3, 9.0 μg/m3, 9.0 μg/m3, 219.2 μg/m3, respectively, for total inhalable dust, mercury, lead and yttrium. The ranges are very wide. Surface samples from employees’ skin and granulometric analysis were also carried out. The overview shows that all the stages and processes involved in lamp recycling are concerned by the risk of hazardous substances penetrating into the bodies of employees, although exposure of the latter varies depending on the processes and tasks they perform. The conclusion of this study strongly recommends the development of a new generation of processes in parallel with more information sharing and regulatory measures.  相似文献   
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