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961.
Transport profoundly affects energy use and carbon dioxide emissions in the tourism sector. The Wulingyuan Scenic Area (WSA), a natural heritage destination in China, is chosen for the case study. The energy consumption and carbon emission of 10 types of tourism transportation modes at the destination are measured and analyzed using a bottom‐up approach for the period of 1979 to 2010. Scenarios were created to project the effects of single and multiple factors on energy consumption and carbon emission by tourism transportation during 2011‐2020. The results showed the following: (a) there is a large difference in energy consumption and carbon emission per capita and per kilometer per capita among the 10 vehicle modes; (b) the monthly energy consumption and carbon emission of tourism transportation differed significantly, the month with the highest (October) are respectively 6.8 and 4 times that of the lowest month (January); (c) the highest annual growth rate of energy consumption and carbon emission are respectively as 32.16% and 27.98% during 1979‐2010; and (d) the amount of energy consumption and carbon emission in the multiple factor scenarios are lower than that in the reference and single factor scenarios during 2011‐2020.  相似文献   
962.
莱茵衣藻(Chlamydomonas reinhardtii)是一种重要的模式生物,其miRNA的发现相对较晚.为系统化地预测分析莱茵衣藻的miRNA,采用比较基因组和同源比对相结合的方法,根据mi Rbase中已知的莱茵衣藻miRNA序列以及前体的特点,并且基于莱茵衣藻的全基因组对其miRNA的前体序列和成熟miRNA进行系统的分析和筛选,使用unigene和JGI的莱茵衣藻相关序列数据库对预测结果进行靶基因预测和功能的分析.最终发现可能存在的miRNA 36条,其前体结构符合miRNA前体的基本特征且具有高度的同源性,两个数据库所得相匹配靶基因分别为64和32条,其中部分是与莱茵衣藻各项生命活动相关的基因.本研究表明莱茵衣藻的基因组中具有可能存在的新miRNA家族,并且部分有高度匹配的靶基因,为其后续研究提供了可靠的理论支持.  相似文献   
963.
以河蚬为受试生物,以存活率、呼吸抑制率为测试终点,研究了沉积物和上覆水中重金属Pb、Cd对底栖生物的毒性效应,并探讨了沉积物中酸挥发性硫化物(acid volatile sulfide,AVS)和同时提取金属(simultaneously extracted metals,SEM)对重金属生物有效性的影响。结果表明,沉积物中Pb、Cd对河蚬致死效应较低,当Pb、Cd浓度分别为400、100 mg獉kg-1,连续暴露21 d时,致死率低于20%;沉积物中Pb、Cd对河蚬14 d的呼吸抑制率EC50分别为519和151 mg獉kg-1;上覆水中Pb和Cd离子浓度较低,对生物毒性效应贡献可以忽略;SEM/AVS值和生物呼吸抑制率有着明显的线性相关性,当SEMPb/AVS1,SEMCd/AVS0.6时,重金属对河蚬有明显的毒性效应。  相似文献   
964.
对事故过程突变模型的建立和突变分析研究现状进行了综述,并展望其发展趋势。  相似文献   
965.
In the first, the paper gave a retrospective analysis on the comprehensive assessment of circular economic development. According to the requirement of improving resource & environment efficiency, the paper designed an analytical framework for a comprehensive assessment of regional circular economic growth, which consists of the goal, object and technical line of the comprehensive assessment of regional circular economic development. Given that, the paper discussed the criterion for choosing the assessment index, the approaches of index's weighing determination, the means of data standardization, and the reference system of assessment index value and so on. According to the framework of regional circular economic development evaluation, the paper made a comprehensive evaluation of Jiangsu Province's circular economic development. The result shows that from temporal change, Jiangsu Province's circular economic development had different stages; from the spatial comparison, there is variance among different regions, which could be divided into different types according to the spatial variance and the relation between the development of circular economy and the aggregative index number. There was a remarkable correlation between circular economic development level and GDP or the 2nd industry GDP. Finally, the ?aper gives some suggestions on how to promote the development of drcular economy in Jiangsu Province.  相似文献   
966.
川中丘陵区土地资源的可持续利用——以乐至县为例   总被引:1,自引:0,他引:1  
川中丘区是四川省粮食经济作物的主产区,土壤肥沃、耕地少、土地利用复杂。以乐至县为例,探讨了该县土地资源的可持续利用。  相似文献   
967.
968.
陈曦川  李琳 《灾害学》1998,13(2):33-36
为加强洪灾研究工作,做好灾前预评估、灾中跟踪评估、灾后详细评估工诈,应用地理信息系统(GIS)技术,建立起海河流域西三洼(东淀洼、文安茬、贾口控)洪灾遥感监测背景信息系统。  相似文献   
969.
Contrast with artificial environment, the multi-level self-organizational system of nature has great gain. Sustainable material environment should respect nature: non-rubbish and super-cycle quality of natural ecosystem offers the material source of human development, fractal structure of nature offers new field of space and information source to this high-density and information-based society, dissipative structure of nature links the new system of energy with whole ecosystem organically, and life-chain regulation is the base of sustainable life environment. Nature guarantees the physical healthy environ- ment by its all-dimension healthy factor, constructs the mental healthy environment by its quality of co-ordinate and chaos, so that guarantees the whole emergence of sustainable development on the 'super-science' level In the view of sustainable development, construction, green economy and human health are basic fields. With the concept of ecosystem regulation, we can relate these fields organically and fulfill the task of human health, welfare and sustainable development. Ecosystem regulation is the base of sustainable development's new paradigm.  相似文献   
970.
Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.  相似文献   
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