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601.
交通系统碳交易实现途径研究   总被引:1,自引:0,他引:1  
由于交通运输行业的移动点源碳排放不同于电力和钢铁等固定排放点源,具有不易于管理和监测的特点,且方法学发展滞后,使得大多数碳排放交易系统未将其纳入早期控排范围。本文分析比较了交通系统碳交易方法学的发展状况,将碳交易项目开发潜在领域归纳为4类:道路交通领域,涉及到的方法学比较复杂,有十几种之多;城市轨道交通领域,主要采取ACM0016和CM-028-V01方法学;航空运输领域,至2014年10月尚未有适用于该领域的方法学获得批准;铁路运输领域,涉及到的方法学主要是AM0101。并分别各领域计算出相应的潜在减排量。分析了交通系统3个碳交易项目案例,其中,已在北京环境交易所挂牌的不停车电子收费系统碳开发项目,认可的温室气体清单为:基准线排放量27 078.936 103 t CO2e;项目排放量20 975.456 103 t CO2e;泄露0;项目减排量6 103 t CO2e。已完成碳核查报告的城市燃料替换公共交通项目,第一年减排量计算结果为:基准线排放量218 333 t CO2e;项目排放量158 824 t CO2e;泄露0;项目减排量59 509 t CO2e。正在开发的城市轨道公共交通项目,预计在整个10年的计入期内可以产生减排量2 057 064 t,平均每年205 706 t。基于案例分析,提出在总量控制碳交易试点下的交通系统碳交易项目测量、报告、核查建设要点:1建立交通温室气体排放数据统计、核算和管理体系。2编制城市交通体系温室气体清单。3参与制定《交通行业温室气体排放核算与报告指南》。4建立节能减排管理制度和团队,系统化、规范化管理企业能源消耗以及温室气体排放。  相似文献   
602.
响应曲面法优化固相反硝化的工艺条件   总被引:2,自引:0,他引:2  
以一种新型可降解材料PLA/PHBV共混物为碳源和生物膜载体,对硝酸盐污染水进行反硝化脱氮。在温度为(29±1)℃,pH为(7.5±0.2)条件下,利用响应曲面法考察了进水硝态氮浓度、水力停留时间(HRT)和出水硝态氮浓度之间的关系,建立了以出水硝态氮浓度为响应值的二次多项式回归模型,模型预测值与实验值能很好吻合。方差分析结果表明,进水硝态氮浓度和HRT及其交互作用对响应值均具有显著性影响(P<0.01)。  相似文献   
603.
Box-Behnken响应曲面优化铁炭微电解降解结晶紫   总被引:1,自引:1,他引:0  
在单因素实验的基础上,以结晶紫脱色率为评价指标,铁炭比、反应时间与曝气量为考察因素,采用Box-Be-hnken响应曲面法优化铁炭微电解降解结晶紫的工艺条件,同时得出相应的数学模型。实验表明,在结晶紫初始浓度为100mg/L和体积为300 mL,pH为3,反应时间为80 min,铁屑的投加量为20 g,铁炭质量比为2∶1,曝气量为20 L/h的条件下,铁炭微电解对结晶紫的脱色率可达到89.6%。通过Box-Behnken响应曲面可知,铁炭比、反应时间、曝气量以及铁炭比和反应时间的交互作用对结晶紫的脱色率均有显著影响,其中曝气量对脱色率的影响尤为显著;回归模型决定系数R2=0.9067,P=0.039,表明此模型拟合程度良好,且模型显著。铁炭微电解降解结晶紫最佳的工艺条件为:铁炭比为2.4∶1,反应时间为84 min、曝气量为40 L/h,脱色率为93.25%,回归模型的预测值与测定值偏差率为2.26%。  相似文献   
604.
In the present study, response surface methodology (RSM) based on the Box-Behnken design (BBD) was employed to investigate the effects of the different operating conditions on the removal of the fungicide (Vapam) onto soil modified with perlite using sorption process. The process parameters such as pH of the fungicide solution (2, 5 and 8), temperature (15, 25 and 35°C), shaking time (2, 13 and 24 h) and the percentage of perlite in the modified soil (0, 2 and 4 %) were investigated using a four-factor-three-level Box-Behnken design at an initial fungicide concentration of C0 = 1.6 mg/L as a fixed input parameter. A second-order quadratic model suggested the optimum conditions to be as follows: fungicide solution pH of 3.57, temperature of 15°C, shaking time of 3.5 h and 4% of perlite in the modified soil which resulted in the improvement of Vapam sorption. Under optimum conditions, the fungicide (Vapam) removal was predicted 12.88 μg/g by BBD. The confirmatory experiments were conducted and the results revealed that the fungicide removal was 13.14 μg/g which indicated that the predicted and the observed values of response (Vapam removal) were in close agreement. Therefore, the soil modified with perlite holds good potential for Vapam sorption. This is the first report on fungicide Vapam sorption onto soil modified with perlite using statistical experimental design employing response surface methodology.  相似文献   
605.
The paper aims to explore the implementation of an eco-design methodology and the related software platform (G.EN.ESI – Green ENgineering dESIgn) within technical departments of a manufacturing firm. The G.EN.ESI eco-design methodology is based on the life cycle thinking concept and the software platform is conceived as a set of inter-operable software tools able to efficiently exchange data among them and with the traditional design systems (i.e. CAD, PDM and PLM). A multinational company, designing and producing household appliances, adopted the proposed methodology and related software platform for redesigning two cooker hood models with the aim to improve their environmental performances. Design and engineering departments evaluated the methodology and platform impact on the product development process, as well as the platform inter-operability with traditional design tools. The results indicate that methodology and software platform satisfy the requirements of the enterprise in terms of: (i) degree of expertise and training requirement on this subject, (ii) low impact in a consolidated design process and, (ii) good level of inter-operability among heterogeneous tools. However, the testing results highlight the necessity of a further platform optimisations in terms of software integration (single workbench made by integrated software tools with the same graphical user interface).  相似文献   
606.
The aim of this paper is to identify principal factors controlling the Degree of Sustainable Development of Mineral Resources (DSDMR) of mining cities and then to measure their DSDMR and reveal their developing trends. To do this, 78 Chinese mining cities are used as an example. These cities are classified on a hierarchical level of the DSDMR in order to support decision-making of sustainable development. Six principal factors controlling the DSDMR are recognized using factor analysis. They are used to measure the DSDMR of the Chinese mining cities and their developing trends. The results show that in terms of the type of mineral resources, the DSDMR decreases from petroleum to multi-resources to non-metal to coal to metal cities. It decreases also from middle to old to young aged cities and from eastern to central to western cities in geographical location. In addition, large and very large cities have higher DSDMR values than middle- and small-sized cities. These Chinese mining cities are classified into six clusters by cluster analysis, which forms the basis for policy making.  相似文献   
607.
Mineral economics is the academic discipline that investigates and promotes understanding of economic and policy issues associated with the production and use of mineral commodities. While its origins can be traced back at least 200 years to the writings of David Ricardo and other early Classical economists, it emerged as a separate academic field only after World War II and then primarily in the United States. As a separate academic discipline, its roots are found in mining schools that needed to consider the milieu in which minerals are sold. While geologists, mining engineers, and others with technical backgrounds were largely responsible for creating the first stand-alone mineral-economics programs, ultimately trained economists became participants as well. Moreover, even after the rise of mineral-economics departments, most of the research in the field continued and continues to be carried out in other academic units, including traditional economic departments and engineering schools, as well as in government agencies, nonprofit research organizations, consulting firms, and international organizations.  相似文献   
608.
An important feature of export-oriented production in mineral-rich developing countries for almost three decades after 1960 was the growth of state-owned enterprises. For the phosphate industry, this was reflected in the expansion of companies such as Office Cherifienne des Phosphate (OCP) in Morocco and the Jordan Phosphate Mines Company (JPMC). There was a strategic importance of the industry for these nations and the large capital outlays necessary for phosphate and fertilizer production expansion often required considerable government assistance because of the perceived high risks of private investment in the industry.  相似文献   
609.
During the past five years, industry analysts have proclaimed that metal prices are in the early phase of a ‘super cycle,’ driven primarily by Chinese industrial expansion. Academic economists have generally been very skeptical about the presence of long cycles. A time-series econometric analysis by Cuddington and Jerrett [2008. Super cycles in real metals prices? IMF Staff Pap. 55(4), in press], however, has used band-pass filtering techniques to isolate super cycles in the prices of six metals traded on the London Metal Exchange (the ‘LME6’). This paper extends the search for super-cycle behavior to three additional metal products that are critical in the early phases of industrial development and urbanization: steel, pig iron, and molybdenum (a key ingredient in many steel alloys). There is strong evidence of super cycles in these three metals, although their timing differs to some extent from the super cycles found for the LME6.  相似文献   
610.
The global gold market has recently attracted a lot of attention and the price of gold is relatively higher than its historical trend. For mining companies to mitigate risk and uncertainty in gold price fluctuations, make hedging, future investment and evaluation decisions, depend on forecasting future price trends. The first section of this paper reviews the world gold market and the historical trend of gold prices from January 1968 to December 2008. This is followed by an investigation into the relationship between gold price and other key influencing variables, such as oil price and global inflation over the last 40 years. The second section applies a modified econometric version of the long-term trend reverting jump and dip diffusion model for forecasting natural-resource commodity prices. This method addresses the deficiencies of previous models, such as jumps and dips as parameters and unit root test for long-term trends. The model proposes that historical data of mineral commodities have three terms to demonstrate fluctuation of prices: a long-term trend reversion component, a diffusion component and a jump or dip component. The model calculates each term individually to estimate future prices of mineral commodities. The study validates the model and estimates the gold price for the next 10 years, based on monthly historical data of nominal gold price.  相似文献   
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