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251.
Sustainability is a key challenge for humanity in the context of complex and unprecedented global changes. Future Earth, an international research initiative aiming to advance global sustainability science, has recently launched knowledge–action networks (KANs) as mechanisms for delivering its research strategy. The research initiative is currently developing a KAN on “natural assets” to facilitate and enable action-oriented research and synthesis towards natural assets sustainability. ‘Natural assets’ has been adopted by Future Earth as an umbrella term aiming to translate and bridge across different knowledge systems and different perspectives on peoples’ relationships with nature. In this paper, we clarify the framing of Future Earth around natural assets emphasizing the recognition on pluralism and identifying the challenges of translating different visions about the role of natural assets, including via policy formulation, for local to global sustainability challenges. This understanding will be useful to develop inter-and transdisciplinary solutions for human–environmental problems by (i) embracing richer collaborative decision processes and building bridges across different perspectives; (ii) giving emphasis on the interactions between biophysical and socioeconomic drivers affecting the future trends of investments and disinvestments in natural assets; and (iii) focusing on social equity, power relationships for effective application of the natural assets approach. This understanding also intends to inform the scope of the natural asset KAN’s research agenda to mobilize the translation of research into co-designed action for sustainability.  相似文献   
252.
This study analyzes whether the ideological orientation of a newspaper has an influence on the salience of skeptical arguments (trend, attribution, impact, and response skeptics) in the coverage of climate change in the UK, Germany, and Switzerland, and examines whether certain newspaper titles act as advocates of the skeptical countermovement. A quantitative content analysis of a broad newspaper sample for each country over the course of one year (June 2012–May 2013) was conducted. The results reveal that conservative newspapers do not amplify skeptical voices in general; the difference between conservative and more liberal outlets is only found in the case of impact and response skepticism. Second, in each country, certain conservative newspapers are particularly open to skeptical arguments.  相似文献   
253.
随着人类社会的不断发展,人们生产生活活动的加剧,片面追求经济效益的工业超标排放、生活垃圾污染、恶意的植被破坏等行为造成了自然生态系统的进一步恶化,也给水生环境带来了极大破坏,人类在尝到水生环境破坏的苦果后,开始积极加强环境保护,并深入探索水生环境修复技术。基于此,本文对水环境修复相关概念及其主要技术进行了分析,以期能够进一步提升水环境治理成效,促进人与自然的和谐发展。  相似文献   
254.
中国进入WTO以来与欧盟棉花贸易的虚拟水资源总量研究   总被引:2,自引:0,他引:2  
中国在与欧盟国家的商晶贸易中,直接进口的是初级农产品,但闻接进口的却是隐藏在这些农产最中的虚拟水.研究这些潜在的水资源,对缓解我国水资源压力,保障粮食安全具有重要的现实意义.本文采用联合国粮农组织FAO的CROPWAT Model计算模型,借助CropWat for Windows计算软件,从资源当量转换的角度出发,计算中国自进入WTO以来与欧盟国家的棉花贸易中水资源转换以及虚拟水贸易情况.计算结果表明,2003-2005年中国在与欧盟的棉花贸易中,间接进口了151.28×106m3的水资源,相当于节约了国内同等数量的水资源.本文可以为解决中国日益短缺的水资源问题提供有益参考.  相似文献   
255.
Coalbeds are an attractive geological environment for storage of carbon dioxide (CO2) because CO2 is retained in the coal as an adsorbed phase and the cost of injection can be offset by enhanced coalbed methane (ECBM) production. This paper presents the findings of a CO2 storage feasibility study on coalbeds in the Wyodak-Anderson coal zone of the Powder River Basin, Wyoming, USA, using reservoir characterization and fluid flow simulations. A 3D numerical model of the Big George coal was constructed using geostatistical techniques, with values of cleat and matrix permeability and porosity constrained through history-matching of production data from coalbed methane (CBM) wells in the field area.Following history-matching, several ECBM and CO2 storage scenarios were investigated: shrinkage and swelling of the coal was either allowed or disallowed, a horizontal hydraulic fracture was either placed at the injection well or removed from the model, the number of model layers was varied between 1 and 24, and the permeability and porosity fields were constructed to be either homogeneous or heterogeneous in accordance with geostatistical models of regional variability. All simulations assumed that the injected gas was 100% CO2 and that the coalbed was overlain by an impermeable caprock. Depending on the scenario, the simulations predicted that after 13 years of CO2 injection, the cumulative methane production would be enhanced by a factor of 1.5–5. Including coal matrix shrinkage and swelling in the model predicted swelling near the injection well, which resulted in a slight reduction (10%) in injection rate. However, including a horizontal hydraulic fracture in the model at the base of the injection well helped mitigate the negative effect of swelling on injection rate. It was also found that six model layers were needed to have sufficient resolution in the vertical direction to account for the buoyancy effects between the gas and resident water, and that capturing the heterogeneous nature of the coal permeability and porosity fields predicted lower estimates of the storage capacity of the Wyodak-Anderson coal zone.After noting that gravity and buoyancy were the major driving forces behind gas flow within the Big George coal, several leakage scenarios were also investigated, in an effort to better understand the interplay between diffusion and flow properties on the transport and storage of CO2. The modeling predicted that the upward migration of gas due to the buoyancy effect was faster than the diffusion of CO2 and therefore the gas rapidly rose to the top of the coalbed and migrated into overlying strata when an impermeable caprock was not included in the model.  相似文献   
256.
Science guides search and rescue after the 2006 Philippine landslide   总被引:1,自引:0,他引:1  
A rockslide-debris avalanche destroyed the remote village of Guinsaugon in Southern Leyte, Philippines, on 17 February 2006. Although search and rescue procedures were implemented immediately, the scale of the landslide and a lack of information about its nature resulted in unfocused and imprecise efforts in the early days of the operation. Technical support was only introduced five days after the event, provided by a team of volunteer geologists, geophysicists, and meteorologists. By the time search and rescue operations were transferred to specific target sites, however, the chances of finding survivors trapped under the rubble had diminished. In such critical situations, speed, accuracy, and the maximum appropriation of resources are crucial. We emphasise here the need for a systematic and technically informed approach to search and rescue missions in large-scale landslide disaster contexts, and the formulation of better disaster management policies in general. Standard procedures must be developed and enforced to improve how civil authorities respond to natural calamities.  相似文献   
257.
Chloramines,in practice,are formed onsite by adding ammonia to chlorinated drinking water to achieve the required disinfection.While regulated disinfection byproducts(DBPs)are reduced during chloramine disinfection,other DBPs such as iodinated(iodo-)DBPs,that elicit greater toxicity are formed.The objective of this study was to investigate the impact of prechlorination time on the formation of both halogen-specific total organic halogen(TOX)and iodo/chlorinated(chloro-)DBPs during prechlorination/chloramination in source waters(SWs)containing iopamidol,an X-ray contrast medium.Barberton SW(BSW)and Cleveland SW(CSW)containing iopamidol were prechlorinated for 5–60 min and afterwards chloraminated for 72 hr with ammonium chloride.Chlorine contact time(CCT)did not significantly impact total organic iodine(TOI)concentrations after prechlorination or chloramination.Concentrations of total organic chlorine(TOCl)formed during prechlorination did not significantly change regardless of pH and prechlorination time,whileTOClappearedtodecreaseafter 72 hrchloraminationperiod.Dichloroiodomethane(CHCl_2I)formation during prechlorination did not exhibit any significant trends as a function of p H or CCT,but after chloramination,significant increases were observed at pHs 6.5 and 7.5 with respect to CCT.Iodo-HAAs were not formed during prechlorination but were detected after chloramination.Significant quantities of chloroform(CHCl_3)and trichloroacetic acid(TCAA)were formed during prechlorination but formation ceased upon ammonia addition.Therefore,prechlorination studies should measure TOX and DBP concentrations prior to ammonia addition to obtain data regarding the initial conditions.  相似文献   
258.
徐闯  徐鹏  王刚  张守献  汪卫东 《环境工程》2013,31(3):25-27,62
分析了孤岛油田二元驱污水特性,针对其乳化油较多,粒径大小分布不均,且较稳定的特点,设计了具有大锯齿结构特征的反相破乳剂分子结构,并合成新型高效反相破乳剂WRD-34,评价了药剂的除油性能。在孤岛孤四联合站应用此新型反相破乳剂开展破乳除油现场试验,二元驱污水的破乳效果得到明显提高,含油量由处理前的514~1 202mg/L降低到13.2~54.0 mg/L。  相似文献   
259.
目的 研究6A01-T5铝合金和304不锈钢异种金属间的缝隙腐蚀行为规律。方法 采用常温常压浸泡腐蚀方法,结合SEM、EDS、XRD和白光干涉检测,对6A01-T5铝合金/304不锈钢缝隙结构在碱性Na Cl溶液中的腐蚀行为进行研究。结果 6A01-T5铝合金/304不锈钢缝隙腐蚀表现为在缝口处产生沿缝口方向的凹陷渠,在缝内,以局部减薄和腐蚀坑为主,并随着腐蚀时间的延长,腐蚀程度逐渐加重。不同区域腐蚀产物的形貌和成分组成不尽相同,缝外暴露区的腐蚀产物表现为晶体颗粒状,主要成分为Ca CO3和Al(OH)3等铝的腐蚀产物。缝口附近沿缝口方向形成一层有明显界线的腐蚀产物覆盖层,缝隙内部的腐蚀产物相对较少,表现为尺寸相对较小的结块,主要成分为Al(OH)3等铝的腐蚀产物。结论 在6A01-T5铝合金与304不锈钢非电连接情况下,6A01-T5铝合金/304不锈钢缝隙内2种金属分别独立发生缝隙腐蚀,因2种金属在腐蚀过程中争夺O2,使得304不锈钢对6A01-T5铝合金的缝隙腐蚀起到抑制作用。  相似文献   
260.
在室内受控模拟条件下开展实验,研究了在19、23、27、31、35℃5个水温梯度下鲴鱼对铜绿微囊藻和水质的影响。研究结果表明,在不同水温下,鲴鱼对铜绿微囊藻具有较强的控制作用,实验结束时铜绿微囊藻密度减少至初始密度的18%~30%,摄食率和消化率分别为6.83×104~8.32×104cells/(g·d)、93%~98%;叶绿素a的去除率为68%~88%;实验组TP、TN去除率分别为22%~25%、20%~38%,对照组的分别为80%~94%、28%~40%。对照组NH+4-N浓度变化很小(0.071~0.073 mg/L),而实验组氨氮浓度显著增大(2.222~3.645 mg/L),分别为初始值的31、34、42、51和46倍。  相似文献   
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