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231.
笔者将传统中医学理论与企业安全生产风险管理相结合,在事故致因、事故预防、安全管理等方面,借鉴中医的预防思想、整体观念、五行学说、辨证施治等理论方法,分析研究指出:企业发生安全事故如同人体得病,正气不足是发病的内在根据,邪气入侵是发病的重要条件。因此,发生事故的根本原因在于企业本身;要从研究企业自身的影响安全生产诸要素之间的相互滋生和相互制约的关系入手,加强事故预防工作,坚持整体性的原则,辨证分析事故原因,加大企业生产安全的精神和物质保障,才能全面提高企业的生产安全风险管理水平。  相似文献   
232.
中国消防行业ODS淘汰中的招标体系设计   总被引:1,自引:0,他引:1  
讨论在中国消防行业臭氧层损耗物质的淘汰行动中采用招标这种市场手段实现淘汰资助有效和合理分配的可能性,提出了设计ODS淘汰招标该体系的原则,并按照中国消防行业的具体情况分析,该招标体系的核心内容。论述实施体系的不确定性及可能的对策。  相似文献   
233.
In order to evaluate ecological risk of agrochemicals in agricultural environment, single and joint toxic effects of an important herbicide and a typical heavy metal on root elongation of crops were investigated. Seeds of the three crops including wheat (Triticum aestivum), Chinese cabbage (Brassica pekimensis) and soybean (Glycine max) as the main crops in northeast China were exposed to acetochior as a herbicide and lead (Pb) as a heavy metal using the pot-culture method, and meadow brown soil as one of the main soils distributed in northeast China was applied in the investigation. The results indicated that the interactive effects of the two pollutants on root elongation of the three crops were very complicated although they had markedly significant (P〈0.01) linear interrelationships based on the regression analyses. When the concentration of added Pb^2+ reached 200 mg/kg, acetochlor and Pb had an antagonistic effect on the inhibition of root elongation of the three crops. However, acetochlor and Pb had significantly (P〈0.05) synergic effects on the inhibition of root elongation when concentration of added Pb^2+ was up to 1000 mg/kg. At the low concentration of added Pb, joint toxicity of acetochlor and Pb was more dependent on the concentration of Pb. Among the three crops, wheat was the most sensitive to the toxicity of Pb and Chinese cabbage was the most sensitive to the toxicity of acetochlor.  相似文献   
234.
氯气事故风险预测评价方法初探   总被引:1,自引:0,他引:1  
依据区域氯气事故调查的实例研究,求得在不同气象条件下,氯气事故发生的概率。再应用近地面大气污染物扩散模式,预测化工厂液氯钢瓶泄漏事故对周围环境的影响范围及程度,进行环境风险评价。并提出液氯钢瓶外泄事故的防范措施。  相似文献   
235.
We review published stratigraphic, archaeological and pedosedimentary evidence in order to reconstruct the history of soil erosion in China. Documentary evidence of climatic and flood events of the Yellow River and modern hydrological and meteorological data are synthesised to analyse the history of past human activity and its effects on soil erosion intensity during four nested periods of time during the Quaternary. The most intensive period of erosion during the Quaternary was in the Holocene. During the Holocene, intervals of intensive soil erosion occurred at 7500–7000 BP, 200 BCE–0 CE, 1000–1600 CE (Christian era) and during the 1930s, 1950s and the later part of the 1960s of the last century. Large-scale human activity including warfare during early Chinese history, population migration, the inner wars in 1930s, the Cultural Revolution and the recent national campaign to aid soil and water conservation are all closely related to the rate of soil erosion on the Loess Plateau and to sediment loads in the Yellow River. Overall, soil erosion during the transition from dry-cool to wet-warm climates was more intense than during wet-warm and cool-dry climatic episodes, but serious accelerated soil erosion has occurred during the last 2,500 years because of man-induced devastation of vegetation and other anthropogenic disturbance of the environment. Modern rates of soil erosion on the Loess Plateau are a combination of both intensive natural and human-induced erosions and are some four times greater than occurred in the geological past. The recent implementation of soil and water conservation measures has decreased sediment load in the Yellow River by 25%.  相似文献   
236.
随着官媒时代的终结,以微信公众号为代表的新媒体的盛行,强烈地冲击着传统纸媒。微信公众号能够增加期刊与读者群之间的“粘性”,从而扩大期刊的学术影响力和社会知名度。在中国地理资源期刊网微信公众号的运行实践基础上,系统总结期刊微信融平台经营的实践与经验,并以《地理研究》等数据为例,阐述微信推送对期刊产生的综合作用,以期为科研微信融平台的运行提供指导和借鉴意义。研究结果表明:(1)科研微信融平台上生产好微推需遵守十四条原则、十一条创意要求;(2)坚持不懈地在微信公众号上发送消息,可以增加编辑与读者之间的交流、拓展读者范围、增加文章的下载量和被引量,从而树立学术期刊的品牌形象,提升期刊的学术影响力;(3)集群化的科研微信融平台的运行,一定要注意共同维护平台形象、谁制作谁负责、合理安排发文量和发文时间、个刊微平台实现互补等。持续地创意和推出微推,需要长期坚持,把期刊编辑和学术研究、移动互联时代、全媒体手段等积极“融”起来,实现期刊由传统纸质出版向富媒体出版、期刊由文献生产者向学科与社会集成型知识服务提供平台的两大根本性转型,才是期刊的根本出路。  相似文献   
237.
通过采集黄土高原中部沿黄流域57个浅层地下水水样,采用定性(Gibbs模型、Na端元和离子相关关系)和定量(正向演替模型)分析方法探究了该地区地下水水化学特征、沿程变化规律和控制因素.结果表明,黄土高原中部沿黄流域浅层地下水均呈弱碱性;优势阴阳离子分别为HCO3-和Na+;水化学类型以HCO3-Ca-Mg为主,占40%.研究区地下水主要离子自北向南变化趋势有所差异,其中Cl-浓度保持动态稳定,SO42-、HCO3-、Mg2+和Na+浓度沿程增加,而NO3-、Ca2+和K+浓度沿程降低,矿产资源开发是研究区地下水SO42-重要来源,而强烈的阳离子交替吸附作用是引起Na+富集的重要因素.研究区地下水溶质来源主要受岩石风化作用控制,以硅酸盐岩石风化为主;大气输入、人类活动和岩石风化对地下水溶质的相对贡献分别为5%±3%、6%±13%和89%±13%.此外,下垫面因素改变、人类活动以及气候变化通过改变地下水补给与排泄等过程直接或间接的影响了地下水水量和水质.本研究结果将为黄河流域和其他类似地区当前和未来的地下水质量管理项目提供参考.  相似文献   
238.
为阐明中国湖泊细菌群落的生物地理分布格局及驱动机制,基于已发表文献,收集了228个湖泊的浮游或沉积物细菌门水平分类数据和环境因子数据进行分析.结果表明:中国湖泊浮游细菌群落的优势类群为变形菌门(Proteobacteria,35.92%)、放线菌门(Actinobacteria,25.03%)和拟杆菌门(Bacteroidetes,10.77%),沉积物中的优势类群为变形菌门(Proteobacteria,40.37%)、绿弯菌门(Chloroflexi,8.74%)和拟杆菌门(Bacteroidetes,8.55%).中国湖泊浮游细菌距离衰减程度显著低于沉积物细菌;湖泊细菌群落结构在北方、南方、青藏高原的空间差异显著,北方水体及沉积物中细菌的距离衰减模式均不显著,南方水体中显著但沉积物中不显著,青藏高原水体及沉积物中均显著.浮游细菌优势类群中除Proteobacteria外,Actinobacteria (南方>北方>青藏高原)和Bacteroidetes (青藏高原>北方>南方)的丰度在三个地区均具有显著差异;沉积物细菌优势类群Proteobacteria (北方>南方>青藏高原)、Chloroflexi (南方>北方>青藏高原)、Bacteroidetes (青藏高原>北方>南方)的丰度在三个地区均具有显著差异.影响北方湖泊浮游细菌群落分布的主要环境因子是溶解性有机碳,南方是溶解氧,青藏高原是硝酸盐氮;影响北方湖泊沉积物细菌群落分布的主要环境因子是总氮和pH值,南方是总磷,青藏高原是pH值.空间扩散限制与环境筛选作用共同塑造了中国湖泊细菌的生物地理分布格局.扩散限制对浮游细菌的影响小于沉积物细菌,对青藏高原湖泊浮游及沉积物细菌影响最大,对北方湖泊浮游及沉积物细菌影响最小;环境筛选作用对青藏高原湖泊浮游及沉积物细菌影响最大,对南方湖泊浮游细菌及北方湖泊沉积物细菌影响较小.  相似文献   
239.
Trace-element contamination poses a serious threat to China's ecology, environment, food safety, and human health. Human exposure to potentially toxic trace elements is predominantly attributed to the consumption of vegetables, especially leafy vegetables, grown on metal-contaminated soil. In the present study, the concentrations of Cd in Chinese cabbage were found to decrease at an exponential rate from the outermost layer to the inner core, while there was a small change in Pb content from the 1st to the 16th layer of the plant, suddenly decreasing at the 17th layer. Although there was a little difference between the maximum permissible concentration (MPC) and the mean Cd content in the plant, from the 1st layer to the 10th layer in the edible part of Chinese cabbage, Cd concentrations were 1.1–2.5 times higher than the MPC. The Pb concentration in the whole plant was 1.9 times higher than the MPC, while the 17th layer to the 25th layer of Chinese cabbage was safe for consumption. Health risk assessment indicated that the surface layer of Chinese cabbage might cause harm to human health, especially to children, in view of cancer risk and non-cancer risk.  相似文献   
240.
金华典型中药材产地环境地球化学研究   总被引:1,自引:0,他引:1  
在金华市主要中药材种植区采集耕作层土壤和中药材样品,分析其重金属含量,并从环境地球化学角度分析中药材重金属超标的原因.结果表明,白术(Rhizoma Atractylodis Macrocephalae)、玄参(Radix Scrophulariae)和浙贝母(Bulbus Fritillariae Thunbergii)中Cd超标率分别为64.3%、40.0%和47.2%,白术、玄参和元胡(Rhizoma Corydalis)中Cu超标率分别为35.7%、10.0%和5.9%.从中药材对重金属的选择性吸收、种植区的土壤环境、地形地貌和气候条件等方面研究发现,气候温暖湿润,地形陡峭,岩石在风化成土过程中淋溶作用强烈,从土壤母质、淋溶层到土壤表层pH值逐渐降低,土壤酸化是导致中药材Cd和Cu含量超标的主要原因.  相似文献   
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