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991.
黑土区土壤侵蚀经济损失价值估算及其特征分析——以黑龙江克拜东部黑土区为例 总被引:2,自引:0,他引:2
论文在GIS技术支持下,依据环境经济学原理,利用2005年的坡面侵蚀和沟蚀数据,对黑龙江克拜东部黑土区由土壤侵蚀造成的直接经济损失进行了定量估算;在此基础上,将黑土区土壤侵蚀经济损失与西北黄土高原地区、北方土石山区、西南岩溶区进行了对比分析。结果表明:研究区2005年由土壤侵蚀所造成的直接经济损失总价值约为9414.20×104元,占当地种植业总收入的17.19%,部分乡镇损失价值占种植业收入的1/4以上。将黑土区土壤侵蚀经济损失与我国其他水蚀区对比发现:东北黑土区虽以轻度侵蚀为主,土壤侵蚀量固然不能与黄土高原相提并论,但由于黑土腐殖质含量高、养分丰富,轻度侵蚀即可造成严重的养分流失,其单位面积土壤侵蚀直接经济损失价值是黄土高原的3~4倍。 相似文献
992.
通过艾萨炉投产以来“烟气、烟尘”测试数据在车间、分厂生产控制中所起作用的分析,阐述艾萨炉“烟气、烟尘”测试的重要性。对工艺制酸烟气实现烟气量、烟尘、烟气成份在线监测的必要性提出看法。 相似文献
993.
The intertidal midge Clunio, which reproduces on exposed rocky seashores, becomes enclosed in an irregularly shaped air bubble during short submersion
by incoming waves. This water-repellent property of Clunio’s cuticle is caused by a complete cover of hydrophobic microtrichia offering an effective surf tolerance. These microtrichia
not only trap a thin air layer above the cuticle but also maintain a larger air bubble between the insect’s ventral side and
legs. The effectiveness of the water repellence was quantitatively characterised on the basis of a known model (Crisp and
Thorpe, Discuss Faraday Soc 3:210–220, 1948). The parameters of the model are the contact angle θ (>90°) at the contact line of air/water/microtrichia and the distance between individual microtrichia and their radius. When
the microtrichia are 1.1 μm apart and have a radius of 0.1 μm and an estimated contact angle θ of 140°, the air layer is stable against hydrostatic pressures of up to 3 m water column. As shown by a modified version
of the model, considerably larger air bubbles can be trapped by the microtrichia cover of the legs up to distances of 0.5 mm
from the body. The widely spaced (about 8 μm apart) and longer setae of Clunio are not involved in the formation of air layers and air bubble. 相似文献
994.
Stefan Hochrainer Reinhard Mechler Georg Pflug 《Mitigation and Adaptation Strategies for Global Change》2009,14(3):231-250
This paper discusses the applicability of crop insurance for the case of Malawi and explores the potential impact of climate
change on the viability of the Malawi weather insurance program making use of scenarios of climate change-induced variations
in rainfall patterns. The analysis is important from a methodological and policy perspective. By combining catastrophe insurance
modeling with climate modeling, the methodology demonstrates the feasibility, albeit with large uncertainties, of estimating
the effects of climate variability and climate change on the near- and long-term future of microinsurance schemes serving
the poor. By providing a model-based estimate of insurance back-up capital necessary to avoid ruin under climate variability
and climate change, along with the associated uncertainties and data limitations, this methodology can quantitatively demonstrate
the need for financial assistance to protect micro-insurance pools against climate-induced insolvency. This is of major concern
to donors, NGOs and others supporting these innovative systems, those actually at-risk and insurers providing insurance. A
quantitative estimate of the additional burden that climate change imposes on weather insurance for poor regions is of interest
to organizations funding adaptation. Further, by linking catastrophe modeling to regionalized climate modeling, the analysis
identifies key modeling inputs necessary as well as important constraints. We end with a discussion of the opportunities and
limits to similar modeling and weather predictability for Sub-Saharan Africa beyond the case of Malawi.
相似文献
Reinhard MechlerEmail: |
995.
T. A. Persson 《Mitigation and Adaptation Strategies for Global Change》2009,14(5):399-408
It is argued that there are at least five reasons for the Northeast states of the United States to implement a regional emission
trading scheme for carbon dioxide despite the lack of federal policy regulations: goodwill, learning, political influence,
risk management and competitiveness interests. Using an energy-economy model, the carbon price to bring the firms into compliance
with a 10% reduction by 2020 is estimated to be 20-150 US$ per ton C. There have been discussions about linking the ongoing
EU Emission Trading Schemes to the Northeast state initiative. The prime argument is that such a linkage would encourage a
change of the federal US policy, which has traditionally followed action taken at the state level. Emissions trading with
binding mitigation commitments could thus be demanded and accepted also on federal level. This paper demonstrates that the
impact of linkage on permit prices depends on the reduction target in the European scheme: A low EU target results in a net
flow of permits to the Northeast scheme, while a 40% EU reduction target results in a net flow of permits from the Northeast.
Flow of permits from the Northeast state must be compensated for by the EU because the United States is not a party of the
Kyoto Protocol. The EU must therefore buy permits in allowances recognized in the Kyoto regime in an amount equal to the net
flow of permits from the Northeast states.
相似文献
T. A. PerssonEmail: |
996.
分析了我国现阶段城市建筑垃圾处置现状和隐患,介绍了城市建筑垃圾减量化、资源化和无害化处置技术和其重要性、必要性和可行性。 相似文献
997.
998.
本文以胜利一号露天矿为例,通过解译近40年来矿区周边的遥感影像图片,对矿区周边的景观类型和景观格局变化进行回顾性评价,结果表明:(1)目前胜利一号露天矿周边景观以草原景观为主,75.41%的景观为草原景观,其中以克氏针茅草原所占面积最大,占整个评价区面积的60.22%,其次为羊草草原景观(占11.58%)。(2)胜利一号露天矿周边景观类型在近40年来发生了明显变化,草原景观不断减少,而人工景观类型却在不断增加2,000年以后人工景观增加幅度最大,2010年人工景观类型面积是2000年的3.54倍。(3)胜利一号露天矿周边土壤质地正逐步由低湿化向中生化和砾石质化转变,草原景观类型也发生了一定变化,与1973年相比2,010年克氏针茅草原面积增加了14.22%,而羊草草原面积却降低了53.6%。(4)人工景观的增加使得矿区周边整个景观更趋于多样化,景观分布也趋于均匀,而景观优势度指数降低,景观斑块密度逐渐增大,最大斑块指数、平均斑块周长面积比、最近邻体距离、蔓延度指数逐渐减小,景观斑块趋于小型化,使景观异质性增加,景观破碎化加大。(5)人工景观的增加使草原景观内部的多样性和均匀度正在遭受破坏;而且随着草原景观中克氏针茅草原面积的不断增加,草原景观的优势度指数不断增加。 相似文献
999.
煤炭脱固硫技术现状及实验探讨 总被引:1,自引:0,他引:1
从当前环境状况入手,分析了目前脱固硫技术的现状、方法,并针对铜川高硫煤进行了物理洗选脱硫实验,提出了进一步固硫技术研究的设想。 相似文献
1000.
对水污染源在线监测系统比对监测过程中的监测条件、样品采集、实验室分析及数据质量和有效性等全过程的质量保证和控制措施进行探讨,以保证其监测数据的科学性、准确性、可靠性和合法性。 相似文献