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121.
Adaptation Options Strategies for Hazards and Vulnerability Mitigation: An International Perspective
C.?Emdad?HaqueEmail author Ian?Burton 《Mitigation and Adaptation Strategies for Global Change》2005,10(3):335-353
The broad objective of this special issue of Mitigation and Adaptation Strategies for Global Change is to address some of the gaps in our knowledge and understanding of the policies, programs, and measures that might be applied
to natural hazards and their impacts in an era of climate change. Given the global impacts of climate change and world-wide
pattern of increasing losses from natural hazards we necessarily adopt an international perspective. The specific goals of
the special issue are to: (a) encompass experiential aspects, emphasizing current practice of mitigation and its associated
measures, and their results; and (b) explore primary or root causes of alarming shifts in human and economic costs of environmental
extremes. Special emphasis is placed on how human activities are playing a key role in enhancing vulnerability to NTEE (nature-triggered
environmental extremes), quite independently from the anthropogenic causes of climate change. The goals are also (c) to examine
costs, risks, and benefits (of all kinds including social, political, ecological) of mitigation, and adjustment and adaptation
measures; and (d) analyze policy implications of alternative measures. These components are expected to make significant contributions
to policy considerations – formulation, implementation and evaluation. There is much uncertainty about the rate of climate
change; however, the fact of increase of the atmospheric temperature in the last century is no longer a subject of scientific
or policy debate. Due to such changes in the geophysical parameters, certain types of nature-triggered environmental extreme
events are likely to continue to increase. How global warming will affect regional climates and pertinent variables is not
well known, limiting our ability to predict consequential effects. This factor poses serious constraints against any straightforward
policy decisions. Research findings of the work of this volume reaffirm that human dimensions, specifically our awareness
and decision-making behavior, are powerful explanatory factors of increasing disaster losses. Disaster mitigation through
addressing human, social, and physical vulnerability is one of the best means for contributing to ‘climate change adaptation
plans’, and sustainable development goals. Recent lessons from various countries have depicted that the formulation of mitigation
strategies cannot be exclusively top-down as it requires social, political, and cultural acceptance and sense of ownership.
An interactive, participatory process, involving local communities, produces best expected outcomes concerning mitigation,
preparedness, and recovery. An emerging consensus is that there is a need to move towards the ‘mission’ of the International
Strategy for Disaster Reduction which aims at building disaster resilient communities by promoting increased awareness of
the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human,
social, economic and environmental losses due to natural hazards and related technological and environmental disasters. Sharing
of best practices and lessons globally is certain to produce more efficiency and understanding in policy and decision making. 相似文献
122.
123.
针对煤质粉末活性炭最显著的热危险特性——自燃危险性进行试验。采用粉尘层最低着火温度测定系统对煤质粉末活性炭进行自燃试验,测定煤质粉末活性炭的最低着火温度;采用SDT Q600热重分析仪测定煤质粉末活性炭在氮气和空气气氛中以20℃/min的速率升温至700℃时的热解和燃烧特性,通过TG/DTG曲线计算其着火温度,并进行热稳定性评价。粉尘层自燃试验结果表明,煤质粉末活性炭最低着火温度为400℃,具有自燃危险性,易形成阴燃;氮气气氛中热解试验表明,热解过程经历了室温~120.0℃和280.0~700.0℃两次轻缓失重阶段,646.44℃时挥发分热失重速率最大,对应热失重速率峰值为0.082 6%/℃,自燃危险性较低;空气气氛中燃烧试验表明,燃烧过程经历了室温~95.5℃和300.0~600.0℃两次剧烈失重阶段,分别为吸附水分受热蒸发和氧化生成的有机官能团分解脱附导致,565.35℃时挥发分热失重速率最大,对应热失重速率峰值为13.20%/min,粉末较强的氧气吸附效应和较低的导热系数导致其自燃倾向较高,火灾危险性较大。 相似文献
124.
薄膜覆盖减少化肥养分流失研究 总被引:7,自引:1,他引:6
我国化肥的利用率低,使用量又不断增长,增加了农业面源污染问题的严重性.本研究针对化肥流失主要通过水带走的特性,进行大田试验种植玉米,利用薄膜覆盖所施用的化肥,实现"肥与水隔离",以减少化肥流失.试验一方面观察了不同施肥处理二季甜玉米的生长和产量,另一方面测定了作物对肥料的利用率以及地表径流养分含量.结果表明,在本土壤条件下甜玉米只需施用常规施肥量的70%即可达到高产.甜玉米收获后土壤中碱解氮、有效磷、有效钾的含量比不经薄膜覆盖的显著提高,其顺序为100%施肥量+覆膜70%施肥量+覆膜100%施肥量、70%施肥量不施肥.氮、磷、钾肥料的表观利用率分别为42%~87%、0%~3%和5%~15%,覆膜处理一般高于不覆膜处理,特别是在高施肥量情况下更为明显.通过8次径流水的收集测定,无薄膜覆盖的施肥处理的地表径流N、P和K平均浓度分别为27.72、2.70和7.07 mg.L-1,薄膜覆盖技术处理降低N、P、K浓度的效果分别达到了39.54%、28.05%、43.74%,对于减少农业面源污染和水体富营养化可起到明显效果. 相似文献
125.
为了快速监测水体悬浮有机物的数量,文章采用密封法测定COD,研究了池塘水体悬浮物及固体干物质样品的COD值与燃烧热值及灼烧减重之间的定量关系。结果表明:池塘水体悬浮物及固体干物质样品的COD值与燃烧热值及灼烧减重之间存在显著的相关关系。而且池塘水体悬浮物的COD值与燃烧热值之间的线性回归关系极显著,回归方程为,燃烧热值(J/L)=12.34COD(mg/L)+329.9。给定燃烧热值与有机碳的量以及与有机物量之间的换算系数,就可以推算出池塘悬浮有机物的数量。研究提出了一种池塘水体悬浮有机物的间接定量方法。 相似文献
126.
矿山开采生产主要的环境影响是生态影响,以抚顺新宾榆树铁矿为例,利用影子工程法对矿山开采进行环境经济损失分析,包括生态资源的经济损失和生态系统功能受到影响的经济损失,可用于矿区环境经济损益分析并作为相关建设项目的借鉴。 相似文献
127.
Keeping the blood flowing—plasminogen activator genes and feeding behavior in vampire bats 总被引:1,自引:0,他引:1
Tellgren-Roth A Dittmar K Massey SE Kemi C Tellgren-Roth C Savolainen P Lyons LA Liberles DA 《Die Naturwissenschaften》2009,96(1):39-47
The blood feeding vampire bats emerged from New World leaf-nosed bats that fed on fruit and insects. Plasminogen activator,
a serine protease that regulates blood coagulation, is known to be expressed in the saliva of Desmodus rotundus (common vampire bat) and is thought to be a key enzyme for the emergence of blood feeding in vampire bats. To better understand
the evolution of this biological function, we studied the plasminogen activator (PA) genes from all vampire bat species in
light of their feeding transition to bird and subsequently mammalian blood. We include the rare species Diphylla ecaudata and Diaemus youngi, where plasminogen activator had not previously been studied and demonstrate that PA gene duplication observed in Desmodus is not essential to the vampire phenotype, but relates to the emergence of predominant mammalian blood feeding in this species.
Plasminogen activator has evolved through gene duplication, domain loss, and sequence evolution leading to change in fibrin-specificity
and susceptibility to plasminogen activator inhibitor-1. Before undertaking this study, only the four plasminogen activator
isoforms from Desmodus were known. The evolution of vampire bat plasminogen activators can now be linked phylogenetically to the transition in feeding
behavior among vampire bat species from bird to mammalian blood.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
128.
采用好氧间歇淋洗培养法,对洱海流域内的农田、菜地土壤样品培养2周,研究土壤氮的矿化及其影响因素.结果表明,表层土壤2周氮矿化量平均为65.54mg/kg.不同农田利用方式下,表层土壤氮矿化量的平均值为露地菜田粮田大蒜田.土壤氮素矿化以硝态氮为主,且随着土壤深度的增加而降低.土壤氮矿化同全氮、有机质含量呈明显的正相关关系,与pH值呈负相关;氮矿化与无机氮含量、C/N之间无显著关系.全氮、有机质和pH值是影响该流域农田土壤矿化的主要因子. 相似文献
129.
Heavy metal (Pb,Zn) uptake and chemical changes in rhizosphere soils of four wetland plants with different radial oxygen loss 总被引:4,自引:0,他引:4
Lead and Zn uptake and chemical changes in rhizosphere soils of four emergent-rooted wetland plants; Aneilema bracteatum,
Cyperus alternifolius, Ludwigia hyssopifolia and Veronica serpyllifolia were investigated by two experiments: (1) rhizobag filled with
“clean” or metal-contaminated soil for analysis of Pb and Zn in plants and rhizosphere soils; and (2) applied deoxygenated solution for
analyzing their rates of radial oxygen loss (ROL). The results showed that the wetland plants with di erent ROL rates had significant
e ects on the mobility and chemical forms of Pb and Zn in rhizosphere under flooded conditions. These e ects were varied with
di erent metal elements and metal concentrations in the soils. Lead mobility in rhizosphere of the four plants both in the “clean”
and contaminated soils was decreased, while Zn mobility was increased in the rhizosphere of the “clean” soil, but decreased in the
contaminated soil. Among the four plants, V. serpyllifolia, with the highest ROL, formed the highest degree of Fe plaque on the root
surface, immobilized more Zn in Fe plaque, and has the highest e ects on the changes of Zn form (EXC-Zn) in rhizosphere under both
“clean” and contaminated soil conditions. These results suggested that ROL of wetland plants could play an important role in Fe plaque
formation and mobility and chemical changes of metals in rhizosphere soil under flood conditions. 相似文献
130.
分析了盘锦市湿地由于不合理的开发利用,导致生态功能受损状况;为防止湿地资源的过度开发,保护湿地生态系统的结构、物种、功能效应,使湿地资源永续利用,提出了具有可操作性的恢复措施。 相似文献