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361.
ABSTRACT: Water resource and water quality management planning depend, to a large degree, on forecasts of industrial activity and population projections. A flexible economic data base is especially important where planning follows varying formats of geographical and industrial detail. Records of employment and payroll are collected in the administration of Unemployment Insurance (U.I.) programs and are available from State Employment Agencies. These statistics have been collected over a long period of record (thirty-five years). Many years of record are available on punched-cards or magnetic tape and may be arrayed and manipulated by computer. This basic approach has been followed in Virginia. Historical U.I. payroll and employment records for the period 1956 through 1970 were procured on magnetic tape. This data was arrayed by major hydrologic area and by regional planning district. Projections of manufacturing activity were then generated by fitting several exponential equations to annual payroll data in two-digit Standard Industrial Classifications. These exponentials were then extrapolated to provide a range of industrial projections. Other parameters of manufacturing activity were then correlated to the payroll data to generate projections of indexes such as employment, value-added, and gross manufacturing output. U.I. payroll data is now being correlated to parameters in non-manufacturing categories. Projections for industries such as trade and services will link extrapolated payroll data with benchmark correlations of payroll and sales receipts.  相似文献   
362.
ABSTRACT: Median concentrations and instantaneous yields of alachlor, metolachlor, atrazine, cyanazine, and simazine were generally highest at sites in the Lower Susquehanna River Basin and in agricultural subbasins. Instantaneous herbicide yields are related to land use, hydrogeologic setting, streamflow yield, and agricultural row cropping practices. The significance of these relations may be affected by the interdependence of the factors. The percentage of basin area planted in corn is the most influential factor in the prediction of herbicide yield. Instantaneous yields of all five herbicides measured in June 1994 related poorly to averaged 1990–94 herbicide use. Annually averaged herbicide-use data are too general to use as a predictor for short-term herbicide yields. An evaluation of factors affecting herbicide yields could be refined with more-current land use and land cover information and a more accurate estimate of the percentage of basin area planted in corn. Factors related to herbicide yields can be used to predict herbicide yields in other basins within the Chesapeake Bay watershed and to develop an estimate of herbicide loads to Chesapeake Bay.  相似文献   
363.
ABSTRACT: Urban water-quality managers need load estimates of storm-runoff pollutants to design effective remedial programs. Estimates are commonly made using published models calibrated to large regions of the country. This paper presents statistical methods, termed model-adjustment procedures (MAPs), which use a combination of local data and published regional models to improve estimates of urban-runoff quality. Each MAP is a form of regression analysis that uses a local data base as a calibration data set to adjust the regional model, in effect increasing the size of the local data base without additional, expensive data collection. The adjusted regional model can then be used to estimate storm-runoff quality at unmonitored sites and storms in the locality. The four MAPs presented in this study are (1) single-factor regression against the regional model prediction, Pu; (2) least-squares regression against Pu; (3) least-squares regression against Pu and additional local variables; and (4) weighted combination of Pu and a local-regression prediction. Identification of the statistically most valid method among these four depends upon characteristics of the local data base. A MAP-selection scheme based on statistical analysis of the calibration data set is presented and tested.  相似文献   
364.
为从宏观层面上把握我国建筑安全生产水平的差异,因地制宜地采取措施,优化资源配置,在分析我国建筑业安全生产状况的基础上,利用安全事故统计分析原理,从绝对指标和相对指标两个方面构建了区域建筑安全生产水平评价体系;利用熵权法确定各指标权重,引入时间加权平均算子"TOWA"进行二次加权,对2009-2016年我国30个省域的建筑安全生产水平进行了相对优劣排序。结果表明,中部地区建筑业安全生产水平总体高于东部、东北部及西部地区。根据综合评价值将30个省域划分为建筑安全生产水平良好、不足、低下3个层次,进而提出了技术优先策略、管理优先策略及政策优先策略。  相似文献   
365.
应用健康风险评价模型和多元统计方法,对河南省新乡市农村地区浅层地下水2015年11月的水质数据(30眼地下水监测井,15个水质指标)进行分析,评估了对当地农村人口造成的健康风险,探索污染物的空间分异特征,并识别对应污染源。结果表明:30眼监测井的Cr6+、Pb、Cd、Hg、As指标均满足Ⅲ类地下水水质标准,但有29眼监测井存在超标因子,浅层地下水污染形势严峻;污染物通过饮水途径所致健康风险均大于可接受风险水平(1×10-6),浅层地下水不适宜直接饮用;监测井可以划分为A组、B组、C组,A组水体受到原生地质污染、营养污染和盐类污染的共同影响,B组受有机污染、盐类污染影响,C组受原生地质污染、盐类污染、营养污染、有机污染的多重作用。  相似文献   
366.
简要统计了2017年7-8月国内发生的各种环境事件160起,包括沙尘天气4起,污染事件15起,地震44起,山体滑坡和泥石流26起,旱灾10起以及其他自然灾害61起.  相似文献   
367.
简要统计了2016年11-12月国内发生的各种环境事件87起,包括沙尘天气4起,污染事件18起,地震50起,山体滑坡和泥石流6起,以及其他自然灾害9起.  相似文献   
368.
简要统计了2017年3-4月国内发生的各种环境事件117起,包括沙尘天气16起,污染事件26起,地震30起,山体滑坡和泥石流13起,以及其他自然灾害32起.  相似文献   
369.
通过对某钢铁厂2014年发生的事故统计分析,找出事故发生的主要规律和原因,提出预防事故重复发生的措施,达到减少或杜绝事故发生,确保安全生产。  相似文献   
370.
Ultra-deep oil and gas wells have become a new development trend in onshore oil and gas exploitation. However, Ultra-deep oil and gas wellbore casing is with high failure risk due to the harsh environment. It is essential to evaluate the reliability of wellbore casing. This paper assesses the operational reliability of wellbore casing using data statistics and numerical simulation. Firstly, the theoretical model for reliability analysis of wellbore casing is established, and the variables in the model are determined, including rock mechanics, cement ring, and casing string strength factors. Subsequently, considering the random distribution of model variables, many statistics and analyses are performed to determine the distribution parameters of the model variables. Eventually, Monte Carlo based numerical simulations are carried out to obtain the residual strength distribution and the reliability of wellbore casing. The production casing in the ultra-deep well with a depth of 6.5 km in China as an industrial case is used to illustrate the present study. It is observed that this study can be useful to guide a more accurate assessment of the reliability of ultra-deep wellbore casing.  相似文献   
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