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711.
712.
低碳城市是一种实现低碳经济、进行低碳生产与消费、形成低碳生活、建设良性与可持续发展的能源生态体系的城市模式。通过调控城市绿地系统、优化城市开放空间,有利于低碳城市理念下的生态城市建设,实现城市的可持续发展。首先对低碳城市建设与城市绿地系统优化的关系进行了分析;其次对郑州城市绿地系统建设存在的主要问题进行了探讨,借助AreGIS9.3软件分析了郑州市绿地服务区的影响范围;最后基于城市绿地系统优化原则提出四方面的优化建议——注重城市的生态设计;优化绿地系统的空间布局;实现“点”、“线”、“面”的有机结合;实施适度的绿地容量限制;发展立体绿化与推广绿色建筑材料的使用。 相似文献
713.
714.
为探索和创新汶川大地震以及其他灾情灾后青少年心理援助提供科学决策依据,通过对四川灾区民众的调查分析及其对收集的信息资料研究,着重揭示了汶川大地震灾后青少年心理援助的经验:“三个加强”——加强方式、方法、机制“三位一体”对青少年心理援助,“三个强化”——社会、学校、家庭“三位一体”对青少年心理援助的启示。 相似文献
715.
716.
PM2.5在线监测技术概述 总被引:4,自引:0,他引:4
针对PM2.5颗粒物监测技术和PM2.5的监测网络的建设,重点介绍了美国多年来对PM2.5的监测状况,以及采用的Beta射线法、Beta射线光浊度法、微量振荡天平法等监测技术的方法和原理;指出综合国内外多年的监测经验,PM2.5的在线监测需要经过大量手工经典方法数据作为比对和校验,才能给出有效而高质量的PM2.5监测数据。 相似文献
717.
在对水泥生产线篦冷机尾气除尘进行分析的基础上,提出了电除尘改袋式除尘的必要性,可有效控制新型干法窑烟尘和粉尘的排放浓度;针对具体案例的使用结果进行了阐述。 相似文献
718.
Shalamu Abudu J. Phillip King Zhuping Sheng 《Journal of the American Water Resources Association》2012,48(1):10-23
Abudu, S., J.P. King, Z. Sheng, 2011. Comparison of the Performance of Statistical Models in Forecasting Monthly Total Dissolved Solids in the Rio Grande. Journal of the American Water Resources Association (JAWRA) 48(1): 10‐23. DOI: 10.1111/j.1752‐1688.2011.00587.x Abstract: This paper presents the application of autoregressive integrated moving average (ARIMA), transfer function‐noise (TFN), and artificial neural networks (ANNs) modeling approaches in forecasting monthly total dissolved solids (TDS) of water in the Rio Grande at El Paso, Texas. Predictability analysis was performed between the precipitation, temperature, streamflow rates at the site, releases from upstream reservoirs, and monthly TDS using cross‐correlation statistical tests. The chi‐square test results indicated that the average monthly temperature and precipitation did not show significant predictability on monthly TDS series. The performances of one‐ to three‐month‐ahead model forecasts for the testing period of 1984‐1994 showed that the TFN model that incorporated the streamflow rates at the site and Caballo Reservoir release improved monthly TDS forecasts slightly better than the ARIMA models. Except for one‐month‐ahead forecasts, the ANN models using the streamflow rates at the site as inputs resulted in no significant improvements over the TFN models at two‐month‐ahead and three‐month‐ahead forecasts. For three‐month‐ahead forecasts, the simple ARIMA showed similar performance compared to all other models. The results of this study suggested that simple deseasonalized ARIMA models could be used in one‐ to three‐month‐ahead TDS forecasting at the study site with a simple, explicit model structure and similar model performance as the TFN and ANN models for better water management in the Basin. 相似文献
719.
Jae H. Ryu Bryce Contor Gary Johnson Richard Allen John Tracy 《Journal of the American Water Resources Association》2012,48(6):1204-1220
Abstract: Water supply uncertainty continues to threaten the reliability of regional water resources in the western United States. Climate variability and water dispute potentials induce water managers to develop proactive adaptive management strategies to mitigate future hydroclimate impacts. The Eastern Snake Plain Aquifer in the state of Idaho is also facing these challenges in the sense that population growth and economic development strongly depend on reliable water resources from underground storage. Drought and subsequent water conflict often drive scientific research and political agendas because water resources availability and aquifer management for a sustainable rural economy are of great interest. In this study, a system dynamics approach is applied to address dynamically complex problems with management of the aquifer and associated surface‐water and groundwater interactions. Recharge and discharge dynamics within the aquifer system are coded in an environmental modeling framework to identify long‐term behavior of aquifer responses to uncertain future hydrological variability. The research shows that the system dynamics approach is a promising modeling tool to develop sustainable water resources planning and management in a collaborative decision‐making framework and also to provide useful insights and alternative opportunities for operational management, policy support, and participatory strategic planning to mitigate future hydroclimate impacts in human dimensions. 相似文献
720.
Organochlorine pesticides (OCPs) such as DDT and DDE have been detected in the surface 0.2 m of Vertisols in the lower Namoi Valley of north western New South Wales, Australia even though they have not been applied to crops since 1982. However, their presence in the deeper soil horizons has not been investigated. The objective of this study was to determine if OCPs were present to a depth of 1.2 m in Vertisols under irrigated cotton farming systems in the lower Namoi Valley of New South Wales. Soil was sampled from the 0-1.2 m depths in three sites, viz. the Australian Cotton Research Institute, ACRI, near Narrabri (149°36′E, 30°12′S), and two cotton farms near Wee Waa (149°27′E, 30°13′S) and Merah North (149°18′E, 30°12′S) in northern New South Wales, Australia. The OCPs detected and their metabolites were α-endosulfan, β-endosulfan, endosulfan sulphate, DDD, DDE, DDT and endrin. The metabolite DDE, a breakdown product of DDT, was the most persistent OCP in all depths analysed. Endosulfan sulphate was the second most persistent followed by endrin > α-endosulfan > β-endosulfan > DDT and DDD. DDT was sprayed extensively in the lower Namoi Valley up to the early 1980s and may explain the persistence of DDE in the majority of soil samples. Dicofol and Dieldrin, two OCPs previously undocumented in Vertisols were also detected. The movement of OCPs into the subsoil of Vertisols may occur when irrigation or rain transports soil colloids and organic matter via preferential flow systems into the deeper layers of a soil profile. Persistence of OCPs was closely correlated to soil organic carbon concentrations. The persistence in soil of OCP’s applied to cotton crops grown more than two decades ago suggests that they could enter the food chain. Their presence at depths of 1.2 m suggests that they could move into groundwater that may eventually be used for domestic and stock consumption. 相似文献