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341.
    
● Mechanical behavior of MBT waste affected by loading rate was investigated. ● Shear strength ratio of MBT waste increases with an increase in loading rate. ● Cohesion is inversely related to loading rate. ● Internal friction angles are positively related to loading rate. ● MBT waste from China shows smaller range of φ. Mechanical biological treatment (MBT) technology has attracted increasing attention because it can reduce the volume of waste produced. To deal with the current trend of increasing waste, MBT practices are being adopted to address waste generated in developing urban societies. In this study, a total of 20 specimens of consolidated undrained triaxial tests were conducted on waste obtained from the Hangzhou Tianziling landfill, China, to evaluate the effect of loading rate on the shear strength parameters of MBT waste. The MBT waste samples exhibited an evident strain-hardening behavior, and no peak was observed even when the axial strain exceeded 25%. Further, the shear strength increased with an increase in the loading rate; the effect of loading rate on shear strength under a low confining pressure was greater than that under a high confining pressure. Furthermore, the shear strength parameters of MBT waste were related to the loading rate. The relationship between the cohesion, internal friction angle, and logarithm of the loading rate could be fitted to a linear relationship, which was established in this study. Finally, the ranges of shear strength parameters cohesion c and effective cohesion c ´ were determined as 1.0–8.2 kPa and 2.1–14.9 kPa, respectively; the ranges of the internal friction angle φ and effective internal friction angle φ ´ were determined as 16.2°–29° and 19.8°–43.9°, respectively. These results could be used as a valuable reference for conducting stability analyses of MBT landfills.  相似文献   
342.
This work presents an overall introduction to the Station for Observing Regional Processes of the Earth System–SORPES in Nanjing, East China, and gives an overview about main scientific findings in studies of air pollution-weather/climate interactions obtained since 2011. The main results summarized in this paper include overall characteristics of trace gases and aerosols, chemical transformation mechanisms for secondary pollutants like O3, HONO and secondary inorganic aerosols, and the air pollution–weather/climate interactions and feedbacks in mixed air pollution plumes from sources like fossil fuel combustion, biomass burning and dust storms. The future outlook of the development plan on instrumentation, networking and data-sharing for the SORPES station is also discussed.
  相似文献   
343.
    
● The emission reduction causes significant change in organic aerosol composition. ● The atmospheric oxidizing capacity improved during emission reduction. ● The mixed oxygenated organic aerosol contributed higher during emission reduction. Organic aerosol (OA) is a major component of atmospheric particulate matter (PM) with complex composition and formation processes influenced by various factors. Emission reduction can alter both precursors and oxidants which further affects secondary OA formation. Here we provide an observational analysis of secondary OA (SOA) variation properties in Yangtze River Delta (YRD) of eastern China in response to large scale of emission reduction during Chinese New Year (CNY) holidays from 2015 to 2020, and the COVID-19 pandemic period from January to March, 2020. We found a 17% increase of SOA proportion during the COVID lockdown. The relative enrichment of SOA is also found during multi-year CNY holidays with dramatic reduction of anthropogenic emissions. Two types of oxygenated OA (OOA) influenced by mixed emissions and SOA formation were found to be the dominant components during the lockdown in YRD region. Our results highlight that these emission-reduction-induced changes in organic aerosol need to be considered in the future to optimize air pollution control measures.  相似文献   
344.
Effective planning of resources management is important for facilitating socio-economic development and eco-environmental sustainability. Such a planning effort is complicated with a variety of uncertain, dynamic and nonlinear factors as well as their interactions. In this study, an inexact-stochastic quadratic programming with recourse (ISQP-R) method is developed for reflecting dynamics of system uncertainties based on a complete set of scenarios as well as tackling nonlinearities in the objective function to reflect the effects of marginal utility on system benefits and costs. Moreover, since penalties are exercised with recourse against any infeasibility, the ISQP-R can support the analysis of various policy scenarios that are associated with different levels of economic consequences when the promised targets are violated. The developed method is applied to a case study of planning resources management and developing regional ecological sustainability. The results have been generated and are helpful for decision makers in not only identifying desired resources-allocation strategies but also gaining insight into the tradeoff between economic objective and eco-environment violation risk.  相似文献   
345.
Polygonum viviparum, which reproduces sexually and asexually, is widely distributed in the Qinghai-Tibet Plateau, and its reproduction strategies are very sensitive to changes in the environment. This study aimed to elucidate the effect of altitude on the photosynthetic characteristics and reproductive strategies of P. viviparum. This study was conducted to investigate the responses of photosynthetic, vegetative, and reproductive traits of P. viviparum populations along six altitudinal gradients in the eastern part of the Qilian Mountains in China. Our results indicated that, with increasing altitude, the net photosynthetic rate of P. viviparum showed an increasing trend, reaching its maximum value (14.39 μmol m–2 s–1) at 3 700 m above sea level. The transpiration rate showed an increasing trend, followed by a decreasing trend, and the intercellular CO2 concentration did not differ significantly between altitudes. With increasing altitude, the plant height and leaf area of P. viviparum showed a downward trend, the aboveground and underground biomass decreased, and the specific leaf area initially decreased and then increased. However, the leaf greenness index showed an upward trend, and the number of stomata in the upper and lower epidermis of leaves initially increased and then decreased. With increasing altitude, the proportion of inflorescence length per plant (the ratio of inflorescence length to plant height), the proportion of bulbil length per inflorescence (the ratio of bulbil length to inflorescence height), and the proportion of the number of bulbils per inflorescence (the ratio of the number of bulbils to the total number of flowers and bulbils) showed an increasing trend. Air temperature and light intensity are the major environmental factors affecting the photosynthetic characteristics and functional traits of P. viviparum. Thus, P. viviparum is exposed to more environmental stresses and obtains less energy when altitude increases, but it adapts to the harsh alpine environment by increasing the photosynthetic capability per unit area. With increasing altitude, P. viviparum populations may be sustained by investing less energy in vegetation and more in reproduction, especially asexual reproduction. © 2022 Science Press. All rights reserved.  相似文献   
346.
建筑物震害的类比预测方法研究   总被引:7,自引:0,他引:7  
在“同一场地上相似的两幢建筑物,未来具有相似的震害程度”的假设前提下,提出了如何利用一个地区的部分建筑物单体的震害预测结果,对这一地区的其它建筑物单体的震害进行预测的方法,并从结构抗震角度研究了如何用加权Ham-ming距离度量两幢建筑物的相似程度。  相似文献   
347.
震后地震灾情的快速获取是地震应急救援的关键,将多源异构灾情信息进行合理的分类与编码,对增强灾情信息的处理能力具有重要的意义。分析了不同地震灾情获取方法的现状与特点,介绍了几种新兴的灾情获取方法。分析了地震灾情的分类原则与方法,研究了多源异构地震灾情信息的分类体系。阐述了灾情信息的编码方法,提出了多源异构地震灾情的编码结构与编码存储。  相似文献   
348.
不确定性校正对地震危险性分析结果的影响   总被引:2,自引:0,他引:2  
聂永安  陈宇坤 《灾害学》1998,13(4):12-16
对现行地震危险性分析模型中的不确定性校正方法所涉及到的一些问题进行了讨论.以地震烈度的危险性分析为例,说明危险性曲线的衰减系数及不确定性大小是影响校正结果的主要因素.总的趋势是:对低烈度,校正后危险性有所降低,降低幅度达50%以上;对高烈度,校正后危险性有所提高,提高幅度可达数倍以上。  相似文献   
349.
周美琴  宁松  聂文东  赵智国  史培军 《灾害学》2012,(4):103-106,113
基于566户调研数据,对湖南省开展的政策性种植业保险做了深入分析,以期对农业保险的开展和相关政策实施提供有益的参考。调查结果显示:水稻和棉花保险保障程度有限,低于基本物化成本;对相关政策的不理解以及担心得不到赔偿是限制农户购买农业保险的主要原因;农户愿意支付的水稻与棉花的保险费率平均在2.6%~3.0%。建议加强农村基础设施建设,提高农业生产设防水平;结合农民需求和支付意愿,设计合理丰富的保险产品;增加农民收入,加强保险知识教育;加大农业保险宣传,保证基层政府和保险公司良好的公信度。  相似文献   
350.
本文研究了地下管道系统的震害预测及网络系统可靠性分析的方法。它是以地下管道微观破坏机制为根据,以模糊图论为主要计算工具的计算方法。最后,本文给出了天津市煤气管网系统的应用实例,结果表明,本方法有一定的推广应用价值。  相似文献   
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