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排序方式: 共有125条查询结果,搜索用时 15 毫秒
81.
银川市臭氧污染特征及影响因素分析   总被引:2,自引:2,他引:0  
依据2014年银川市6个自动空气监测子站的监测数据,分析银川市臭氧浓度的污染特征,并对夏季臭氧相关气象因子进行分析。结果表明,从监测点位来看,银湖巷站点臭氧浓度最高,宁安大街次之,宁化生活区臭氧浓度最低。从时间变化规律来看,银川市臭氧浓度呈夏季最高,春季次之,秋季、冬季污染较低,其中臭氧月均浓度最大值出现在5月、6月。臭氧日变化呈单峰变化规律,夜间臭氧浓度较低,白天臭氧浓度较高。夏季臭氧浓度与二氧化氮、相对湿度呈显著的负相关性,与气温、风速呈显著正相关性。  相似文献   
82.
测定苯胺类化合物pH控制范围及调节方法的研究   总被引:4,自引:0,他引:4  
介绍了NEDA法反应机理及其酸度、pH调节方法对实验结果的影响,叙述了合理调整pH控制范围及改进pH调节方法,可以得到最大灵敏度、最佳分析效果及理想的实验方法。该方法可在化工、纺织、染料、生态、环境保护等相关领域广泛应用。  相似文献   
83.
Multivariate statistical techniques were used to investigate source apportionment and source/sink relationships for polycyclic aromatic hydrocarbons (PAHs) in the urban and adjacent coastal atmosphere of Chicago/Lake Michigan in 1994–1995. The PAH signatures for the atmospheric particle phase, surface water particle phase and sediments indicate that atmospheric deposition is the major source of PAHs to the sediments and water column particulate phase of Lake Michigan. The PAH signature for the atmospheric gas phase and water dissolved phase indicate an intimate linkage between the lake and its overlying atmosphere. A modified factor analysis-multiple regression model was successfully applied to the source apportionment of atmospheric PAHs (gas+particle). Coal combustion accounted for 48±5% of the ΣPAH concentration in both the urban and adjacent coastal atmosphere, natural gas combustion accounted for 26±2%, coke ovens accounted for 14±3%, and vehicle emissions (gas+diesel) accounted for 9±4%. Each is an identified source category for the region. These results are consistent with the mix of fossil fuel combustion sources and ratios of indicator PAHs.  相似文献   
84.
在微机数据库管理系统中,运行一自编程序,进行试验数据的处理及试验报告的自动打印.使用该程序处理试验数据,不仅速度快,而且内容准确、规范,可大大地提高工作效率.  相似文献   
85.
水样中铵氮测量的不确定度评定   总被引:1,自引:0,他引:1  
通过对铵氮测定过程的分析,找出了影响测定结果的各个分量。影响测定结果的分量主要有:标准溶液、回归曲线、试样平行试验、纳氏试剂分光光度法、分光光度计,取样等。在此基础上对测量的不确定度进行了评定,并按照计量技术规范,给出了标准的表示法。  相似文献   
86.
福建区域工业三废污染比较研究   总被引:2,自引:0,他引:2  
福建各地区工业结构、经济发展水平差距较大,工业三废污染对经济、社会发展造成的压力也不尽相同。选取反映工业三废污染及处理的12项主要指标,通过系统聚类分析方法和因子分析方法,分别定量地研究了2000年福建省各地区工业三废污染及处理情况,并分析了原因,进而提出解决的对策。  相似文献   
87.
The Finnish approach that is starting from the basic human needs of food, housing, mobility and related lifestyles enables us to address the social dimension of sustainable development alongside the ecological and economic dimensions. In this context environmental problems cannot be resolved in isolation from people’s everyday lives, as can happen if environmental policies are based purely on emissions.But it is also worth questioning the potential for national SCP programmes in today’s global markets. Over the last ten years, domestic material flows within the Finnish economy have remained fairly constant, with gains in material efficiency cancelled out by increasing levels of material consumption. However, external material flows and the consequent environmental impacts have steadily increased, and the magnitude and environmental impacts of both imports and exports are approximately the same as for domestic flows. This means that the role of external material flows can no longer be ignored in national SCP policies.It is also important to integrate SCP with climate policies. Finland’s national climate and energy strategy is mainly based on the need to reduce CO2 emissions from energy production and industrial installations, but there is also a need for complementary actions to reduce the carbon footprints caused by private and public consumption.  相似文献   
88.
Predicting species distribution and habitat suitability (HS) modelling, across broad spatial scales, is now a major challenge in marine ecology. The resulting knowledge is of considerable use in supporting the implementation of environmental legislation, integrated coastal zone management and ecosystem-based fisheries management. This contribution considers the identification of seafloor morphological characteristics, together with wave energy conditions, that determine the presence of European lobster (Homarus gammarus); and it predicts suitable habitats over the Basque continental shelf (Bay of Biscay), in summer. The results obtained, by applying Ecological-Niche Factor Analysis (ENFA), indicate that lobster habitat differs considerably from the mean environmental condition over the study area; likewise, that it is restrictive in terms of the range of conditions in which they dwell. The best of the environmental predictors found to be: distance to the rock substrate; Benthic Position Index; wave flux over the seafloor; and the underlying bathymetry. A habitat suitability map was produced, with a high model quality (Boyce index: 0.98 ± 0.06). The most suitable habitat for European lobster are locations at the boundary between sedimentary- and rocky-bottoms, coincident with seafloor depressions with a steep slope, with medium to high wave energy conditions, and located within a range of water depths of 35–40 m. This approach demonstrates the applicability of the method in case studies where only presence data are available, together with the inclusion of environmental variables obtained from different sources.  相似文献   
89.
New methodologies for security risk assessment of oil and gas industry   总被引:1,自引:0,他引:1  
The oil and gas industry forms a vital and large part of the economy of any country. It provides crucial support to transport, manufacturing and energy sectors, produces valuable exports and provides huge employment. This industry along with fertilizer plants, petrochemical plants, etc., which handle hazardous chemicals, are potential targets for deliberate actions by terrorists, criminals and disgruntled employees. The process industries face different levels of threats. It is imperative to analyze the entire threat scenario before taking steps to counter it, otherwise each and every threat will have to be treated as most severe, thus resulting in a huge and wasteful expenditure.The Security Risk Factor Table (SRFT) and a Stepped Matrix Procedure (SMP) have been developed to assess the security risk of oil and gas industry as well as the other chemical process industries. While the SRFT deals with the effects of individual threats, the SMP deals with the cascading/domino effects which a lone, low probability event can cause. A case study of a refinery has been performed to show the application of the ideas presented.  相似文献   
90.
应用因子分析法分析对虾养殖水质   总被引:5,自引:0,他引:5  
本文应用因子分析法分析了影响对虾养成期间水源和养殖用水的主要污染因子。通过分析,浮游植物、细菌、非离子氨和亚硝酸盐氮等因子在不同的水体中表现出不同程度的污染。  相似文献   
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