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301.
2005年以来,黑龙江省社会经济持续稳步发展,截至2017年,全省GDP达到15903亿元,增长近3倍,人均GDP增长2.89倍,城镇化率达到60%,第三产业占全省生产总值比重达到55.82%。与此同时,全省碳排放量从19095万吨增加到27251万吨,增长1.43倍。通过对黑龙江省13年间社会经济数据的系统分析研判,人均GDP、城镇化率、碳排放强度等因素对全省碳排放量影响显著。  相似文献   
302.
周倜  张强  梅宝中 《环境与发展》2020,(1):83-83,85
城市河道黑臭水体对市民生活有严重不良影响,黑臭水体形成复杂、治理难度大。本文通过分析黑臭水体的外源性及内源性成因,明确了黑臭水体来源与治理方向,同时从控源截污、底泥修复、水体净化等方面研究了有效治理城市河道黑臭水体污染的技术,旨在进一步明确其治理策略,以期为有效治理提供参考。  相似文献   
303.
• A dual “waste-to-resource” application of FO was proposed. • Performance of sea salt bittern as an economic FO draw solution was evaluated. • High quality struvite recovery from black water using FO was demonstrated. • Feed pH is a key factor to control the form of recovered phosphorous. A dual “waste-to-resource” innovation in nutrient enrichment and recovery from domestic black water using a sea salt bittern (SSB)-driven forward osmosis (FO) process is proposed and demonstrated. The performance of SSB as a “waste-to-resource” draw solution for FO was first evaluated. A synthetic SSB-driven FO provided a water flux of 25.67±3.36 L/m2⋅h, which was 1.5‒1.7 times compared with synthetic seawater, 1 M NaCl, and 1 M MgCl2. Slightly compromised performance regarding reverse solute selectivity was observed. In compensation, the enhanced reverse diffusion of Mg2+ suggested superior potential in terms of recovering nutrients in the form of struvite precipitation. The nutrient enrichment was performed using both the pre-filtered influent and effluent of a domestic septic tank. Over 80% of phosphate-P recovery was achieved from both low- and high-strength black water at a feed volume reduction up to 80%‒90%. With an elevated feed pH (~9), approximately 60%‒85% enriched phosphate-P was able to be recovered in the form of precipitated stuvite. Whereas the enrichment performance of total Kjeldahl nitrogen (TKN) largely differed depending on the strength of black water. Improved concentration factor (i.e., 3-folds) and retention (>60%) of TKN was obtained in the high-nutrient-strength black water at a feed volume reduction of 80%, in comparison with a weak TKN enrichment observed in low-strength black water. The results suggested a good potential for nutrient recovery based on this dual “waste-to-resource” FO system with proper management of membrane cleaning.  相似文献   
304.
DFT calculations in gas and aqueous solution phases have been performed to study the mechanism of carbamate formation by the absorption of CO2 in 2-amino-2-methyl-1-propanol (AMP). The results reveal the importance of considering the effect of water as solvent for the reaction to proceed. Furthermore water molecules play an important role as a basic reactant leading to stable intermediates formation. These results point at a single-step, third order reaction as the most probable mechanism for the formation of carbamate by the absorption process.  相似文献   
305.
Carbon capture and storage (CCS) may play a central role in managing carbon emissions from the power sector and industry, but public support for the technology is unclear. To address this knowledge gap, and to test the use of discrete choice analysis for determining public attitudes, two focus groups and a national survey were conducted in Canada to investigate the public's perceptions of the benefits and risks of CCS, the likely determinants of public opinion, and overall support for the use of CCS.The results showed slight support for CCS development in Canada, and a belief that CCS is less risky than normal oil and gas industry operations, nuclear power, or coal-burning power plants. A majority of respondents indicate that they would support the use of CCS as part of a greenhouse gas reduction strategy, although it would likely have to be used in combination with energy efficiency and alternative energy technologies in order to retain public support.  相似文献   
306.
Ecologists are increasingly actively involved in conservation. We identify five key topics from a broad sweep of ecology that merit research attention to meet conservation needs. We examine questions from landscape ecology, behavioral ecology, ecosystem dynamics, community ecology, and nutrient cycling related to key topics. Based on literature review and publication trend assessment, consultation with colleagues, and roundtable discussions at the 24th International Congress for Conservation Biology, focused research on the following topics could benefit conservation while advancing ecological understanding: 1. Carbon sequestration, requiring increased linkages to biodiversity conservation; 2. Ecological invasiveness, challenging our ability to find solutions to ecological aliens; 3. Individual variation, having applications in the conservation of rare species; 4. Movement of organisms, integrating ecological processes across landscapes and scales and addressing habitat fragmentation; and 5. Trophic-level interactions, driving ecological dynamics at the ecosystem-level. Addressing these will require cross-disciplinary research under the overarching framework of conservation ecology.  相似文献   
307.
广州城区冬季黑碳气溶胶污染特征及其来源初探   总被引:11,自引:4,他引:7  
于2007年12月至2008年2月利用黑碳(Aethalometer)和气体在线现测仪(Thermo 42i型二氧化硫、43i型氮氧化物争49i型臭氧分析仪)和MAWS自动气象站获得了大气细粒子中每5分钟黑碳气溶胶(BC)浓度,每1小时SO2、NO2、NO和O3浓度和风速、风向等气象因子观测数据.结果发现,黑碳日均值浓度值为10.5±7.7 μg/m3,浓度变化范围为2.7~34.8 μg/m3.非降雨期BC有相对明显的两个峰值和一个谷值;降雨期BC昼间呈单调上升,夜间呈单调降低.通过对BC与气体污染物相关性分析并结合城市污染源分布,发现BC的最主要来源是工业燃煤和机动车尾气排放.  相似文献   
308.
Geological CO2 capture and storage (CCS) is among the main near-term contenders for addressing the problem of global climate change. Even in a baseline scenario, with no comprehensive international climate policy, a moderate level of CCS technology is expected to be deployed, given the economic benefits associated with enhanced oil and gas recovery. With stringent climate change control, CCS technologies will probably be installed on an industrial scale. Geologically stored CO2, however, may leak back to the atmosphere, which could render CCS ineffective as climate change reduction option. This article presents a long-term energy scenario study for Europe, in which we assess the significance for climate policy making of leakage of CO2 artificially stored in underground geological formations. A detailed sensitivity analysis is performed for the CO2 leakage rate with the bottom-up energy systems model MARKAL, enriched for this purpose with a large set of CO2 capture technologies (in the power sector, industry, and for the production of hydrogen) and storage options (among which enhanced oil and gas recovery, enhanced coal bed methane recovery, depleted fossil fuel fields, and aquifers). Through a series of model runs, we confirm that a leakage rate of 0.1%/year seems acceptable for CCS to constitute a meaningful climate change mitigation option, whereas one of 1%/year is not. CCS is essentially no option to achieve CO2 emission reductions when the leakage rate is as high as 1%/year, so more reductions need to be achieved through the use of renewables or nuclear power, or in sectors like industry and transport. We calculate that under strict climate control policy, the cumulative captured and geologically stored CO2 by 2100 in the electricity sector, when the leakage rate is 0.1%/year, amounts to about 45,000 MtCO2. Only a little over 10,000 MtCO2 cumulative power-generation-related emissions are captured and stored underground by the end of the century when the leakage rate is 1%/year. Overall marginal CO2 abatement costs increase from a few €/tCO2 today to well over 150 €/tCO2 in 2100, under an atmospheric CO2 concentration constraint of 550 ppmv. Carbon costs in 2100 turn out to be about 40 €/tCO2 higher when the annual leakage rate is 1%/year in comparison to when there is no CO2 leakage. Irrespective of whether CCS deployment is affected by gradual CO2 seepage, the annual welfare loss in Europe induced by the implementation of policies preventing “dangerous anthropogenic interference with the climate system” (under our assumption, implying a climate stabilisation target of 550 ppmv CO2 concentration) remains below 0.5% of GDP during the entire century.
Koen SmekensEmail:
  相似文献   
309.
欧盟黑碳监测现状及我国开展黑碳监测的建议   总被引:1,自引:0,他引:1  
介绍了欧盟关于黑碳概念的定义及黑碳的来源和危害,着重从政策、技术、实践3个层面分析了欧盟黑碳监测的发展现状。借鉴欧盟的先进发展经验,对我国开展黑碳监测的必要性进行了分析,并提出了相关的发展建议。  相似文献   
310.
利用苏州市2005—2010年土地利用以及能源消耗数据,对苏州市碳排放进行了估算,结果表明,2005—2010年苏州市碳排放呈逐年增加趋势,建设用地是主要的碳源,林地是主要的碳汇。并根据结果提出了关于减少碳排放的几点建议。  相似文献   
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