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1.
This paper presents a computer simulation of reflected and scattered laser radiation for calculating the angle of laser shields performed with the Laser Shield Solver computer program. The authors describe a method of calculating the shield angle for laser shields which protect workers against reflected and scattered laser radiation and which are made from different materials. The main assumptions of the program, which calculates and simulates reflected laser radiation from any material and which can be used for designing shield angles, are presented. Calculations are compared with measurements of reflected laser radiation. The results for one type of laser and different materials which interacted with a laser beam showed that the Laser Shield Solver was an appropriate tool for designing laser shields and its simulations of reflected laser radiation distribution have practical use.  相似文献   
2.
The study aimed to find out the influence of sweating on footwear insulation with a thermal foot model. Simultaneously, the influence of applied weight (35 kg), sock, and steel toe cap were studied. Water to 3 sweat glands was supplied with a pump at the rate of 10 g/hr in total. Four models of boots with steel toe caps were tested. The same models were manufactured also without steel toe. Sweating reduced footwear insulation 19–25% (30–37% in toes). During static conditions, only a minimal amount of sweat evaporated from boots. Weight affected sole insulation: Reduction depended on compressibility of sole material. The influence of steel toe varied with insulation. The method of thermal foot model appears to be a practical tool for footwear evaluation.  相似文献   
3.
With lack of affordable housing being clearly identified as a social and economic exclusion issue for most communities, innovative ways of addressing this deficiency should be considered. Increasingly local communities are engaging with the possibility of direct provision themselves and discussion around this notion has profound implications for community cohesion. One community-based solution gaining popular support within communities, and with government ministers, is the Community Land Trust mechanism. This involves control and ownership of land to help ensure affordable housing is built and remains affordable in perpetuity for the community. The language and difficulties with definition of terms, together with the complexity of engaging relevant stakeholders in a changing policy and legislative framework can be problematic. This may lead to apparent lack of consensus within communities on the way forward. Perceptions of local housing issues and ways to address them are sometimes vague, sometimes diverse but rarely apathetic. This paper includes data from two case studies in North East England, which are examined using interviews with key players, as a means of seeking some practical solutions.  相似文献   
4.
This paper explores how residents of Overtown, a low-income neighbourhood in Miami, Florida, view the positive and negative aspects of their neighbourhood “invironment” through photographs taken by residents. The “invironment” [Bell, M., 2004. An invitation to environmental sociology. Thousand Oaks, CA: Pine Forge Press] alludes to the interactions between environment/surroundings and the human body. Residents involved with a community social justice organisation were provided with a photographic workshop and cameras to visually document the positive and negative aspects of their neighbourhood. These participant photographers provided narratives paired with their photographs which were then exhibited at local community events. During the exhibits, community members’ comments on the photographs were recorded. This paper analyses community issues through both photographs and neighbourhood comments inspired by the photographs. The following themes of importance to residents were derived from the photographs and discussion with residents: Housing, Public Space, Neighbourhood Economy, History, Environmental/Invironmental Issues, Human Capital and Power. These themes were all connected by residents’ concerns about inequality in Overtown compared to other neighbourhoods in Miami.  相似文献   
5.
In the Netherlands there are around 400 “Seveso” sites that fall under the Dutch Major Hazards Decree (BRZO) 1999. Between 2006 and 2010 the Dutch Labour Inspectorate's Directorate for Major Hazard Control completed investigations of 118 loss of containment incidents involving hazardous substances from this group. On the basis of investigation reports the incidents were entered in a tailor-made tool called Storybuilder developed for the Dutch Ministry of Social Affairs and Employment for identifying the dominant patterns of technical safety barrier failures, barrier task failures and underlying management causes associated with the resulting loss of control events. The model is a bow-tie structure with six lines of defence, three on either side of the central loss of containment event. In the first line of defence, failures in the safety barriers leading to loss of control events were primarily equipment condition failures, pre start-up and safeguarding failures and process deviations such as pressure and flow failures. These deviations, which should have been recovered while still within the safe envelope of operation, were missed primarily because of inadequate indication signals that the deviations have occurred. Through failures of subsequent lines of defence they are developing into serious incidents. Overall, task failures are principally failures to provide adequate technical safety barriers and failures to operate provided barriers appropriately. Underlying management delivery failures were mainly found in equipment specifications and provisions, procedures and competence. The competence delivery system is especially important for identifying equipment condition, equipment isolation for maintenance, pre-start-up status and process deviations. Human errors associated with operating barriers were identified in fifty per cent of cases, were mostly mistakes and feature primarily in failure to prevent deviations and subsequently recover them. Loss of control associated with loss of containment was primarily due to the containment being bypassed (72% of incidents) and less to material strength failures (28%). Transfer pipework, connections in process plant and relief valves are the most frequent release points and the dominant release material is extremely flammable. It is concluded that the analysis of a large number of incidents in Storybuilder can support the quantification of underlying causes and provide evidence of where the weak points exist in major hazard control in the prevention of major accidents.  相似文献   
6.
Safety reports are mandatory documents in member states of European Union whenever any threshold limits of amounts of either stored or processed hazardous substances are exceeded. After a short introduction to EU Seveso Directives on major-accident hazards involving dangerous substances and to the transposition and implementation by member states, with a brief comment on last 2012/18/EU Directive (also known as Seveso III directive), the paper focuses on drafting of safety reports for industrial activities involving solid explosives. Specifically, the quantitative assessment of consequences from detonation is tackled respect to the side-on overpressure and the debris production. Both direct and inverse problems are illustrated to determine respectively the overpressure value at a given distance, and the explosive amount that allows respecting the regulations. Their solution is based on either analytic or numerical techniques and being based on recent scientific publications on the matter either evaluates or zeroes nonlinear algebraic equations. The availability of these equations avoids grounding the consequences assessment on diagrams and nomograms that otherwise would lead to interpretation and usage errors besides avoiding the automatic solution of the inverse problem. The paper focuses also on details such as embankment, crater, munitions, rocket propellant, building structure, and wall material that, at different levels, play a role in the assessment of detonation consequences. A discussion on debris formation, the available literature, and the evaluation of the impact probability of fragments on both fixed and moving targets closes the paper.  相似文献   
7.
中国西部能源及矿业开发与环境保护协调发展研究   总被引:4,自引:0,他引:4  
中国西部地区自然环境脆弱且恶劣,但能源及矿产资源分布相对集中,能源及矿业开发已经成为其经济社会发展的支柱产业.本文力图从西部能源及矿业开发与环境保护协调发展、促进资源开发与生态保护的视角,综合辨析出西部地区能源及矿业开发引发的地质环境及生态环境恶化问题,主要包括土壤污染与土地破坏、水资源污染与短缺、矿区大气污染、噪声污染以及采矿诱发的各类地质灾害和生态环境破坏等.文章认为:西部地区矿产资源和能源开发等人为因素引发的地质环境及生态环境恶化问题日益突出,增强西部地区可持续发展能力,确保资源开发与环境保护的协调发展是西部地区提高能源资源保障能力的现实选择,也是转变发展方式、建设“两型”社会的必然要求.为此,本文对西部地区能矿资源开发与环境保护的协调发展提出了相关建议,主要包括:大力推行绿色发展,极开发绿色新能源;加强资源管理与污染控制,建立、健全矿产资源开发环境保护相关法律法规和体系,健全生态补偿机制;通过市场准入制度设立绿色门槛,继续整合小矿山;加强西部资源型城市与沿海地区的区域融合,减少资源开发的负外部性,破除“资源诅咒”;借鉴国际上“责任矿产开发倡议”,提高能源及矿产资源开发利益相关者的参与能力;统筹协调资源税费、地方发展基金,明确资源税的调节作用,健全利益分配机制,设立绿色发展基金;加强能矿资源开发全过程的第三方独立监管,在能源及矿产资源开发过程中实行有效透明的监管等.  相似文献   
8.
Abstract

A commercial formulation of Bacillus thuringiensis Berliner var. kurstaki (BTK), Foray® 48B, was sprayed aerially over four blocks B13, B14, B15A and B15B in an oak forest in Wayne County, Pennsylvania during May 1990. B13 and B14 were sprayed at 75 billion international units (BIU) in 5.91 litres/ha and the other two at 50 BIU in 3.94 litres/ha. Oak foliage was collected at different intervals of time after treatment. Three types of bioassays were conducted against fourth instar gypsy moth larvae, viz., direct feeding of sprayed foliage, feeding on diet containing homogenized foliage, and force‐feeding of foliar extracts. Larval mortalities were converted into international units of BTK activity per unit area (IU/cm2) of foliage. Foliar extracts were also subjected to enzyme‐linked immunosorbent assay (ELISA) to determine the concentration of delta‐endotoxin protein. Regardless of the type of bioassay used, bioactivity of BTK persisted in foliage for about a week in all the blocks. The half‐life of inactivation, DT50, ranged from ca 12 to 22 h. The immunoassay data indicated a shorter duration of persistence (i.e., about 2 d) of the delta‐endotoxin protein, with DT50 values ranging from 10 to 15 h. Formulation ingredients present in Foray 48B played a role in the toxicity of BTK to gypsy moth larvae.  相似文献   
9.
Abstract

Interaction of lindane with silty loam and silty clay loam soils was studied in batch tests at 23, 30 and 37° C. Sorption experiments were carried out at four concentrations and for varying time of contact upto 72 hours. This was followed by desorption studies. No desorption was observed. The sorption data was analysed using sorption equations and evaluating the thermodynamic parameters. The sorption was found to be predominantly entropic in nature and a combined effect of adsorption and chemisorption. The effect of organic matter and other chemical and mineralogical constituents of soils has also been discussed. The sorption with single application of lindane with the two soil types indicates that the insecticide is less likely to reach groundwater.  相似文献   
10.
Abstract

The effect of two tracer dyes [Erio Acid Red (EAR) and Acid Black 48 (AB‐48)] on initial deposits and persistence of Bacillus thuringiensis subsp. kurstaki (Btk) toxin (delta‐endotoxin) was studied after spraying two commercial formulations, Foray® 48B and Foray® 76B, over potted white spruce [Picea glauca (Moench) Voss] seedlings, at a dosage rate of 30 billion international units (BIU) per ha. Spray was applied using a spinning disc atomizer calibrated to deliver droplet sizes similar to those utilized in ultra‐low‐volume (ULV) treatments in operational insect control programs. The sprayed seedlings were left outdoors at the Sault Ste. Marie laboratory for 18 days under natural conditions of sunlight, wind and rainfall. Initial deposits and persistence of delta‐endotoxin protein in spruce foliage were determined by immunoassay [enzyme linked immunosorbent assay (ELISA)] quantification of the delta‐endotoxin. The total protein (inactive plus active) and delta‐endotoxin (active protein) concentrations in the two formulations were determined by a gravimetric procedure and by ELISA respectively.

The initial deposit levels of the toxin on foliage were not markedly affected by the addition of either of the two tracer dyes, and showed only a narrow range of 1521 to 1625 ng/g foliage (fresh weight) for Foray 48B, and 1789 to 2056 ng/g for Foray 76B. However, the persistence of the toxin was significantly influenced by the presence of the dyes. The toxin persisted in foliage only for 7 d post‐spray When the EAR dye was added to Foray 48B, compared to 10 d when no dye was added. The average half‐life (DT50) of disappearance was 17.4 h for Foray 48B with EAR, and 20.9 h when no dye was present. In contrast, the situation was reversed in Foray 76B, since the duration of persistence was 10 d when EAR was added to Foray 76B, compared to 7 d when no dye was added. The average DT50 was 27.9 h for Foray 76B with EAR, and 22.2 h without the dye. Persistence was the longest (14 d) when the AB‐48 dye was added to Foray 76B, and the DT50 was 44.9 h.  相似文献   
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