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761.
762.
Households respond to earthquake risk in different ways. The main theories explaining human behaviour under threat of earthquakes are reviewed. A survey of households' responses in Tehran and Rasht in Iran to earthquake risks is used to assess the validity of psychological, 'need', socio-cultural and economic theories in explaining behaviour. More support of cognitive and cultural theories is found rather than economic and 'need' theories of earthquake safety measures; this suggests that positive adoption of mitigation measures can be encouraged in terms of cognitive processes through information and education.  相似文献   
763.
In this paper we develop a novel, comprehensive method for estimating the global human carrying capacity in reference to food production factors and levels of food consumption. Other important interrelated dimensions of carrying capacity such as energy, non-renewable resources, and ecology are not considered here and offer opportunities for future work. Use of grain production (rain-fed/irrigated), animal product production (grazing/factory farm), diet pattern (grain/animal products), and a novel water accounting method (demand/supply) based on actual water consumption and not on withdrawal, help resolve uncertainties to find better estimates. Current Western European food consumption is used as a goal for the entire world. Then the carrying capacity lies in the range of 4.5–4.7 billion but requiring agricultural water use increase by 450–530% to 4725–5480 km3, the range based on different estimates of available water. The cost of trapping and conveying such water, will run 4.5–13.5 trillion over 50 years requiring an annual spending increase of 150–400%, straining the developing world where most of the population increase is expected. We reconfirm estimates in the literature using a dynamic model. ‘Corner scenarios’ with extreme optimistic assumptions were analyzed using the reasoning support software system GLOBESIGHT. With a hypothetical scenario with a mainly vegetarian diet (grazing only with 5% animal product), the carrying capacity can be as high as 14 billion. Ecological deterioration that surely accompanies such a population increase would negatively impact sustainable population. Using our approach the impact of ecological damage could be studied. Inter- and intra-regional inequities are other considerations that need to be studied.  相似文献   
764.
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766.
珍珠岩对蚯蚓同步处理污泥-狐尾藻的研究   总被引:1,自引:0,他引:1  
本研究利用太平二号蚯蚓构建生物反应器,以污水处理厂脱水污泥和粉绿狐尾藻作为研究对象,探究添加不同比例的珍珠岩对蚯蚓动物反应器处理混合物的减量化、无害化和资源化效果.结果表明,添加珍珠岩能够显著提高蚯蚓动物反应器同步处理污泥-狐尾藻的效率,经反应器处理后,混合物减量化效果明显,处理后产物的pH、有机质、碱解氮和重金属含量(Cu、Pb、Cr)均表现为明显下降,电导率(EC)和速效磷显著上升.经反应器处理后,产物品质符合在pH6.5的中性和碱性土壤上的施用标准.结果显示,当珍珠岩添加比例为4%时,对动物反应器的实用性和经济性效果最佳.  相似文献   
767.
Influenza A virus poses a major public health concern and is associated with annual epidemics and occasional pandemics. Influenza A H3N2 viruses, which are an important cause of human influenza, can infect birds and mammals. Contaminated undercooked poultry products including eggs with avian influenza virus constitute a possible risk of transmission to humans. In this study, a novel levulinic acid plus sodium dodecyl sulfate (SDS) sanitizer was evaluated for eggshell decontamination. Influenza A H3N2 virus-inoculated chicken eggshells were treated with a 5 % levulinic acid plus 2 % SDS, 2 % levulinic acid plus 1 % SDS, and 0.5 % levulinic acid plus 0.5 % SDS liquid solution for 1 min. Log reductions of viable viruses were observed by plaque assay. The 5 % levulinic acid plus 2 % SDS sanitizer provided the greatest level of influenza A H3N2 virus inactivation (2.23 log PFU), and differences in virus inactivation were observed for the various levulinic acid plus SDS concentrations tested (P ≤ 0.05). To the best of our knowledge, this is the first study demonstrating influenza A H3N2 virus inactivation on eggshells using a novel levulinic acid plus SDS sanitizer. The sanitizer may be useful for reducing egg contamination and preventing the spread of avian influenza virus to humans.  相似文献   
768.
South Asia is one of the most densely populated regions of the world, where despite a slow growth, agriculture remains the backbone of rural economy as it employs one half to over 90 percent of the labor force. Both extensive and intensive policy measures for agriculture development to feed the massive population of the region have resulted in land degradation and desertification, water scarcity, pollution from agrochemicals, and loss of agricultural biodiversity. The social and ethical aspects portray even a grimmer picture of the region with growing poverty mainly, amongst small farmers, food scarcity, and overall poor quality of life. This article reviews the historical perspective of agriculture development in the region and gives a panoramic view of the policy initiatives and their environmental as well as social and ethical spin-offs. The aim is to explore the environmental and ethical dimensions of the agricultural development in South Asia and recommend a holistic approach in formulating plans and programs to combat environmental degradation, hunger, and poverty resulting from unsustainable agricultural practices.  相似文献   
769.
Heavy metal pollution caused by traffic activities is increasingly becoming a great threat to urban environmental quality and human health. In this paper, soils of Kerman urban and suburban areas were collected to assess the potential effects of traffic and other vehicle-related pollution by heavy metal accumulation in soils. Eighty-six samples were collected along streets and from residential and rural sectors, as well as vehicle-related workshops from depth of 0–5 and 15–20 cm and analyzed by flame atomic absorption spectrometry (FAAS) for heavy metals (Cd, Cr, Cu, Pb, Sn and Zn), as well as major elements (Al, Ca, Fe and Mn). Several hot-spot areas were identified in the composite geochemical maps produced based on Geographical Information System (GIS) technology. The majority of the hot-spot areas were identified to be vehicle-related workshops, fuel stations and road junctions. The most polluted hot-spot in the study area was located in soils close to a car battery processing workshop in the southwestern part of Kerman city, with concentrations of Cd (0.32 mg/kg), Cr (169 mg/kg), Cu (250 mg/kg), Pb (5,780 mg/kg), Sn (27.2 mg/kg) and Zn (178 mg/kg) of 1, 8.5, 8.3, 230, 13.5 and 3 times more than the relevant mean concentrations in natural soils, respectively. Traffic pollution has resulted in significant accumulation of heavy metals in soils and sediments, and that level of accumulation varied remarkably among elements. Based on X-ray diffraction analysis, most parts of soils and sediments of the Kerman basement consist of calcite and clay minerals. Abundance of clay minerals and medium to alkaline pH causes low mobility of heavy metals in soils of Kerman.  相似文献   
770.
Canola (Brassica napus L.) is commonly used as a hyper-accumulator for phytoextraction of heavy metals from soil and water. Like many other heavy metals, lead (Pb) contaminates soil, water and air and thus it is a great problem. This study was conducted to investigate toxic effects of Pb on growth and nutrient uptake in four canola cultivars. Each of four cultivars of canola (Con-II, Con-III, Legend and Shiralee) was subjected to four levels of Pb (0, 30, 60 and 90 mg Pb kg(-1) of soil) from lead chloride [PbCl2]. Due to Pb toxicity, plant growth was adversely affected and relatively a severe reduction in root biomass (45.7%) was recorded. The Pb accumulation increased both in shoot and root, the highest being in root. The uptake of different nutrients, i.e., N, P, K, Ca, Mg, Zn, Cu and Mn was reduced (38.4, 32.8, 33.1, 49.6, 7.78, 52.0, 42.6 and 45.9%, respectively) in the shoots and that of N, Fe, Zn, and Cu in the roots (48.5, 33.2, 24.3 and 44.8%, respectively) of all canola cultivars. The root K, P, Zn and Mn and shoot P, Mg and Fe contents were less affected, the concentration of Pb, Ca and Mg in roots of all cultivars. Among canola cultivars Con-II and Con-III performed better than Legend and Shiralee in terms of growth (26.03%) and nutrient accumulation. Overall, plant growth and nutrient accumulation in the canola cultivars was hampered due to the presence of Pb.  相似文献   
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