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301.
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为检验二元联合作用藻红外测试方法的可行性,用Cu~(2+)、Fe3+、Mn~(2+)、Al3+、Cr3+、Hg~(2+)、Cd~(2+)、Pb~(2+)、Zn~(2+)进行了二元联合作用测试实验。结果显示:联合药液的参照浓度与单药液的参照浓度比为0.5:0.25的有15组二元组合,为2.0:1.0的有10组二元组合,为1.0:0.5的有11组二元组合;在9种重金属的36组二元联合作用测试结果中出现拮抗作用、相加作用、协同作用,表明联合作用类型表现出多样性;14组拮抗作用中单组的再现性为50%~100%、多组的再现性的出现率为93%、单组的重现性为67%~100%、多组的重现性的出现率为100%,21组相加作用中单组的再现性为50%~100%、多组的再现性的出现率为86%、单组的重现性为67%~100%、多组的重现性的出现率为100%,1组协同作用重现性67%;36组联合作用测试结果的再现性为50%~100%、再现性的出现率为86%,重现性为67%~100%、重现性的出现率为100%。上述分析可知,9种重金属的36种二元联合作用测试结果具有较好的多样性、再现性、重现性,表明测试条件、藻温测试方法、三指标评价法能够保证藻响应温差和藻响应药品评价结果的质量,参照浓度分析方法、联合作用评价方法能够控制联合作用分析结果的质量;藻响应的有毒有害物都存在敏感浓度,用参照浓度分析方法可分析出藻响应有毒有害物的参照浓度。因此,藻红外测试技术可以用于测试重金属、农药、有机药品、抗生素等的二元联合作用。  相似文献   
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304.
防电磁波辐射的功能性服装   总被引:4,自引:0,他引:4  
电磁波辐射已成为危害人类健康的第四大污染源,如何进行屏蔽是人们日益关注的问题,本文介绍了防电磁波辐射服装的功能及特点,提出了屏蔽服装今后的发展方向.  相似文献   
305.
    
Solar‐driven interfacial water evaporation is a promising strategy to produce clean water by effectively converting abundant solar energy into localized heat. However, many previously reported interfacial evaporation systems are separate and costly. In this work, an all‐in‐one interfacial water evaporator with flexibility, low‐cost, and large‐scale production based on electrostatic flocking technology is proposed. Hydrophilic microfibers (flocks) are vertically planted on the upper side of the textile substrate to enhance the light trapping for photothermal conversion and lower the latent heat for more efficient evaporation. On the other side of the textile, a highly dense and vertically aligned array of hydrophobic flocks are prepared to form a continuous air layer, reducing heat conduction from absorber to bulk water. Taking advantage of those features, the all‐in‐one evaporator achieves a good evaporation rate of 1.32 kg m−2 h−1 for pure water and 1.10 kg m−2 h−1 for seawater. Simultaneously, the evaporator demonstrates resistance to salt accumulation, resulting in its stability in brine. This all‐in‐one evaporator represents an innovative way for designing interfacial evaporators and a convenient approach to mitigate the global freshwater scarcity.  相似文献   
306.
微波辐射处理活性艳蓝KN-R染料溶液的研究   总被引:56,自引:0,他引:56       下载免费PDF全文
在活性炭存在下微波照射能使活性艳蓝KN-R溶液迅速脱色,每g活性炭处理浓度为300mg/L的活性艳蓝KN-R溶液50mL,微波辐射4min脱色率达97.1%.  相似文献   
307.
An important element of resource management and conservation is an understanding of the tradeoffs between marketed products, such as timber, and measures of environmental quality, such as biodiversity. In this paper, we develop an integrated economic-ecological spatial optimization model that we then apply to evaluate alternate forest policies on a 560,000 km2 study region of managed boreal forest in Alberta and British Columbia, Canada. The integrated model incorporates dynamic forest sector harvesting, current levels of oil and gas sector development, coarse-filter or habitat-based old forest indicators, a set of empirical forest bird abundance models, and statistical models of the natural and current fire regimes. Using our integrated model, economic tradeoff curves, or production possibility frontiers, are developed to illustrate the cost of achieving coarse-filter targets by a set time (50 years) within a 100-year time horizon. We found levels of ecological indicators and economic returns from the timber industry could both be increased if spatial constraints imposed by the current policy environment were relaxed; other factors being equal, this implies current policy should be revised. We explore the production possibility frontier's relationship to the range of natural variation of old forest habitat, and show how this range can be used to guide choices of preferred locations along the frontier. We also show that coarse-filter constraints on the abundance of certain habitat elements are sufficient to satisfy some fine-filter objectives, expressed as the predicted abundances of various species of songbirds.  相似文献   
308.
中国的太阳能资源及应用潜力   总被引:9,自引:0,他引:9  
太阳能资源被认为是21世纪最引人注目的可再生能源和洁净能源,为了经济的可持续发展,应该把环境保护和长期利益作为研究目标,文章估算了中国14个城市的太阳能资源,分析了太阳能热水系统和PIVP系统的经济性,研究结果表明,中国的太阳能利用潜力很大,政府应该对其发展发挥重要作用。  相似文献   
309.
    
Plasmonic structures are gaining tremendous interest due to their unique capability to trap light into subwavelength units, beneficial for high efficient light harvesting and related applications. Here, a plasmonic structure realized on a monocrystallized Cu2ZnSnS4 (CZTS) nanosheet‐assembled membrane is presented. This unique CZTS structure exhibits high absorption efficiency (≈92.25%) in a broad solar spectrum (200–2500 nm), leading to a solar desalination efficiency of ≈84.5% under 1 Sun irradiation. This highly efficient broadband absorption is due to the structure induced localized surface plasmon resonance absorption. Besides, owing to its high chemical stability, salty water containing heavy metal ions can be effectively desalinated with a constant long time (>20 h) durability using this CZTS membranes as the absorber. The combination of the robust desalination effect, high stability and durability, as well as the low‐cost and scalable process for production, makes this type of CZTS membranes one of the most competitive desalination candidates.  相似文献   
310.
    
Luminescent solar concentrators (LSCs) are photovoltaic (PV) complementary devices to overcome the mismatch between the Si‐based PV cells, response and the solar spectrum, allowing PV urban integration. Challenges for the luminescent layer include the use of abundant and sustainable natural organic molecules. Here, LSCs composed of a glass container and based on bundles of cylindrical hollow‐core plastic optical fibers filled with aqueous solutions of R‐phycoerythrin (R‐PE), extracted from Gracilaria sp. algae are presented. The R‐PE solutions absorb in the UV/visible spectral range (300–550 nm) and convert this radiation into red‐emission (550–700 nm) with a maximum absolute quantum yield of ≈0.39. In this work, LSCs with distinct geometries are reported, in which the R‐PE emission yields optical conversion efficiency values up to ≈6.88% and ≈4.74% for a planar device and for a bundle of cylindrical LSCs, respectively, which are the largest values known for liquid‐based LCSs using sustainable emitting centres. Moreover, the coupling of the LSCs to commercial Si‐based PV devices yields power conversion efficiency values of ≈0.27% (planar) and ≈23.03 × 10−3%, (bundle). These values illustrate the potential of this approach for the development of natural‐based LSCs meeting the requirements of reliable, sustainable, and competitive energy systems.  相似文献   
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