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401.
近年来 ,恐怖袭击事件威胁着城市公共安全 ,给人们的精神和心理造成极大的创伤和痛苦 ,已引起各国政府、各大媒体的广泛关注。笔者分析了城市公共安全的特点 ,研制了恐怖内心思想的智能阅读车 (IRV) ,通过对进入公共场所的人群进行快速 (数秒内 )检测人体生理参数 (3项指标 ) ,阅读人群的心理、生理、行为特征 ,快速地识别出恐怖分子 ,解决了安全预警滞后的问题 ,建立公共安全的常规通道 (或非常规通道 )。研究与开发的目的是从传统的被动防范转变到主动预控 ,为解决国内外防恐和反恐难题提供了一种新方法。 相似文献
402.
在国内外矿山安全评价领域内,主要以矿山概率风险评价为基础的评价技术,把矿井生产系统中隐患导致事故的概率与隐患造成的损害乘积作为系统状态危险度。隐患发生的概率和造成的损害是通过数据统计获得。该评价方法对隐患发生的概率和损害统计不够规范,缺乏实用性,且只讨论了采用数据的模糊性问题[1]。近年来兴起的数值模拟技术是基于可视化计算软件的一种岩石破裂过程分析方法。笔者提出了用计算机模拟技术进行矿山开采过程中的安全评价新方法,该方法应用材料相似性原理,通过计算机数值模拟,解决针对矿山开采过程中采场结构参数优化、矿柱受力破坏形式、部位、范围及合理性评价等有关地压危害方面的难题。 相似文献
403.
N. Earl Spangenberg 《Journal of the American Water Resources Association》1982,18(1):133-134
ABSTRACT: A watershed in Wyoming was calibrated using both local climatic data and flow from another watershed. An immediate need for entry forced calibration with a limited number of years of data. Regression equations were tested using noncentral “t” and associated power graphs. The equations were presented with recommendation for great care in use. 相似文献
404.
地震活动趋势的多层递阶预报 总被引:1,自引:0,他引:1
多层递阶预报是动态系统的新型统计预报理论,由于它把动态系统看成是一个时变参数系统,因而与客观实际较为符合,预报误差也相对较小,利用它来预报一个地区未来的地震活动趋势,具有一定的实用价值。 相似文献
405.
动态发酵工艺参数的研究 总被引:5,自引:0,他引:5
本文定量地研究了城市生活垃圾滚筒式好氧堆肥处理技术的工艺参数。确定了动态发酵的适宜有机物含量为50 % ~60 % 、含水率为30 % ~50 % ,一次发酵时间为1 ~3 天,二次发酵时间为10 天;一次发酵最佳温度为55 ℃~65 ℃。 相似文献
406.
M. M. Fogel L. Duckstein C. C. Kisiel 《Journal of the American Water Resources Association》1971,7(2):309-316
A probability model for predicting the occurrence and magnitude of thunderstorm rainfall developed in the southwestern United States was tested in the metropolitan Chicago area with reasonable success, especially for the moderate to the extreme runoff-producing events. The model requires the estimation of two parameters, the mean number of events per year and the conditional probability of rain given that an event has occurred. To tie in the data from more than one gage in an area, an event can be defined in several ways, such as the areal mean rainfall exceeding 0.50 inch and at least one gage receiving more than 1.0 inch. This type of definition allows both of the model parameters to be obtained from daily warm-season rainfall records. Regardless of the definition used a Poisson distribution adequately described the number of events per season. A negative binomial distribution was derived as representing the frequency density function for rainfall where several gages are employed in defining a storm. Chicago data fit both distributions very well at events with relatively high return periods. The results indicate the possibility of using the model on a regional basis where limited amount of data may be used to estimate parameters for extensive areas. 相似文献
407.
John W. Labadie 《Journal of the American Water Resources Association》1975,11(1):97-114
ABSTRACT: A surrrogate-prarmeter approach to modeling groundwater basins is presented, which has the following advantages over current simulation-type methods: (i) conducivness to modeling nonhomogeneous and nonisotropic basins; (ii) there is no need to guess boundary conditions if accurate information is not available; (iii) the model is amenable to systematic calibration or identification through the use of optimization techniques; and (iv) compatibility with systematic algorithms for analyzing a wide range of management strategies. Since the parameter identification problem is large-scale and nonconvex, it is decomposed through application of generalized duality theory, into several subproblems of smaller size which are solved independently a number of times in order to achieve an overall solution. Results are presented for a hypothetical system of four interacting wells. 相似文献
408.
Stanley G. Chamberlain Charles V. Beckers G. Paul Grimsrud Roger Don Shull 《Journal of the American Water Resources Association》1974,10(2):199-219
ABSTRACT: To assure attainment and maintenance of desired water quality levels in our rivers and streams, systematic monitoring must be performed. A preliminary phase of the design of water quality surveillance systems is the specification of sampling frequencies and station locations throughout the basin; that is, the development of an adequate space/time sampling plan. The purpose of this paper is to present some quantitative methods which have been developed to identify candidate sets of sampling frequencies and station locations, and to establish priorities for implementing the different frequencies and locations. These methods are useful in the cost/effectiveness trade-off analyses in surveillance system design, and are based on the surveillance system objective of pollution abatement in which it is desired to detect violations in state-federal water quality standards. A spatial priority measure is developed which is dependent both on the water quality profile in the stream and on the information obtained from monitoring stations located in other reaches. Also, a temporal sampling priority rating is presented which is a measure of the effectiveness of the surveillance system with respect to its ability to detect the violations in the standards. To illustrate the quantitative methods, the procedures are applied to the Wabash River Basin. 相似文献
409.
Elliot M. Schneiderman Donald C. Pierson David G. Lounsbury Mark S. Zion 《Journal of the American Water Resources Association》2002,38(5):1323-1347
ABSTRACT: A previous modeling study used the Generalized Watershed Loading Functions (GWLF) model to simulate stream‐flow, and nutrient and sediment loads to Cannonsville Reservoir from the West Branch Delaware River (WBDR). We made several model revisions, calibrated key parameters, and tested the original GWLF model and a revised GWLF model using more recent data. Model revisions included: addition of unsaturated leakage between unsaturated and saturated subsurface reservoirs; revised timing of sediment export; inclusion of urban sediments and dissolved nutrients; tracking of particulate nutrients from point sources; and revised timing of septic system loads. The revision of sediment yield timing resulted in significant improvements in monthly sediment and particulate phosphorus predictions as compared to the original model. Addition of unsaturated leakage improved hydrologic predictions during low flow months. The other model changes improve realism without adding significant model complexity or data requirements. Goodness of fit of revised model predictions versus stream measurements, as measured by the Nash‐Sutcliff coefficient of model efficiency, exceeded 0.8 for streamflow‐0.7 for sediment yield and dissolved nitrogen (N) and 0.6 for particulate and dissolved phosphorus (P). The revised GWLF model, with limited calibration, provides reasonable estimates of monthly streamflow, and nutrient and sediment loads in the Cannonsville watershed. 相似文献
410.
液化石油气钢瓶爆破强度的概率分布研究 总被引:2,自引:0,他引:2
应用数理统计方法,对液化石油气钢瓶爆破强度进行了分析,得到如下2个结论:①在显著度为5%时,描述爆破强度实测值与预测值之比的随机变量符合正态分布;②在置信度为99%时,分析得到了该随机变量分布参数的取值范围。 相似文献