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61.
战场环境下装备保障信息系统安全风险与防护   总被引:1,自引:1,他引:0  
李宇明  耿斌 《装备环境工程》2015,12(2):91-94,124
目的研究战场环境下装备保障信息系统的安全问题。方法从装备保障及装备保障信息系统的概念、分类和复杂战场环境下装备保障信息系统所面临的安全威胁入手,依照五分法把装备保障信息系统安全风险划分为5个等级,推导出风险评估模型,提出实施装备保障信息系统安全防护的技战术策略。结果战场环境下,为确保整个作战进程中装备保障活动安全、有效、稳定地进行,装备保障信息系统防护必须遵循统一协调、综合利用的积极防护原则,采用有效的风险控制措施加以应对。结论通过积极探索和发展装备保障信息安全与防护理论,找准战场环境信息防护中存在的薄弱环节,制定了装备保障信息安全防护策略,加强装备保障信息系统的安全管理工作,最终提高我军装备保障信息系统的防护能力。  相似文献   
62.
(过冷)液体蒸气压(PL)是评价化学品在环境中分配、迁移和归趋行为的重要参数。PL具有较强的温度依附性。发展一种能够精确预测不同环境温度下化学品PL的方法,有助于填补化学品生态风险评估的大量数据缺失。本研究收集整理了661种有机化合物在不同温度下(200~830 K)共计10 478个log PL值。在此基础上,采用偏最小二乘(PLS)回归和支持向量机(SVM)方法,构建了PL的线性和非线性预测模型。结果表明:2种模型均具有良好的拟合度、稳健性及预测能力,SVM模型的预测性能略高于PLS模型(PLS:R2adj.tra=0.912,RMSEtra=0.477,Q2ext=0.910;SVM:R2adj.tra=0.997,RMSEtra=0.092,Q2ext=0.967)。机理分析表明,温度是影响PL的主要因素,温度越高,蒸气压越大;其次,X1sol也影响PL大小,X1sol用来描述分子间的色散作用,分子间色散力越小,蒸气压越大;此外,化合物的氢键个数、极性和分子构型等因素也影响PL大小。采用Wiliams plot方法表征了PLS模型应用域。所建立的模型可用来预测烷烃、烯烃、醇、酮、羧酸、苯、酚、联苯、卤代芳香烃、含N化合物及含S化合物在不同温度下的PL数据。  相似文献   
63.
In the aftermath of a disaster event, and in the absence of trained professionals, many responsibilities are assumed by uninjured citizens who are willing and able to help, such as care of the injured or search and rescue. These citizens are constrained by communications and logistics problems but are less equipped to deal with them as most often they are cut off from any coordinated assistance. The method proposed in this study would increase the survivability of those injured or trapped by a disaster event by providing a facility to allow citizens to coordinate and share information among themselves. This is facilitated by the proposed deployment and the autonomous management of an ad hoc infrastructure that liaises directly with survivors without central control. Furthermore, as energy concerns present critical constraints to these networks, this research proposes a system of categorising information elements within the network to ensure efficient information exchange.  相似文献   
64.
This paper develops a methodology for integrating a land-use forecasting model with an event scale, rainfall-runoff model in support of improving land-use policy formulation at the watershed scale. The models selected for integration are loosely coupled, structured upon a common GIS platform that facilitates data exchange. The hydrologic model HEC-HMS is calibrated for a specific storm event that occurred within central Washington State. The land-use forecasting model, What If? is implemented to forecast future spatial distributions of low-density residential land-uses under low and high population growth estimates. Forecasted land-use distribution patterns for the years 2015, 2025, and 2050 are then used as land-use data input for the calibrated hydrologic model, keeping all other parameters constant. Impacts to the stream discharge hydrograph are predicted as the study area becomes increasingly developed as forecasted by What If?. The initial results of this integration process demonstrate the synergy that can be generated through the linkage of the selected models. The ability to quantifiably forecast the potential hydrologic implications of proposed land-use policies before their implementation offers land-use decision-makers a valuable tool for discerning which proposed land-use alternatives will be effective at minimizing storm water runoff.  相似文献   
65.
通过在Na+-MMT表面生长MoS2来提高窄带隙半导体光生电子分离速率及稳定性.利用阳离子填充法及水热法成功制备了复合光催化剂Na+-MMT/MoS2,并通过FT-IR、SEM、TEM、Raman、XRD、TG、XPS、UV-DRS和ESR等表征进一步证明了材料的成功负载及光、电化学性能. 同时,以有机染料罗丹明B为待降解染料来评价光催化剂的催化性能,发现其在80 min可有效降解罗丹明B,降解率达96%.经过5次循环使用后,Na+-MMT/MoS2复合光催化剂仍具有较好的光催化性能.因此,利用MMT的表面电负性及稳定的片层结构负载MoS2,可形成光生电子迁移通道进一步提高电荷迁移速率及光催化剂的稳定性.本研究可为黏土材料调控窄带隙半导体制备环境友好型光催化剂提供新思路.  相似文献   
66.
In policy support of municipal solid waste (MSW) management, life cycle assessment (LCA) can serve to compare the environmental or economic impacts of two or more options for waste processing. The scope of waste management LCAs generally focuses less attention on future developments, e.g., where will recycling take place, and more on the environmental performance of prototypes, e.g., the incineration of all waste compared to recycling. To provide more robust support for Swiss waste glass-packaging disposal, scenarios of Swiss waste glass-packaging are assessed from a life cycle perspective. The scenarios consist in schemes for the disposal of the total amount of Swiss waste glass-packaging, i.e., different combinations of recycling and downcycling in Switzerland or abroad developed in Part I, Meylan et al. (2013). In this article (Part II), the disposal schemes are assessed with respect to eco-efficiency, an indicator that combines total environmental impacts and gross value added in Switzerland. Results show that no policy alternative guarantees environmental impact reductions and gross value added gains under all developments of exogenous constraints. Downcycling to foam glass in Switzerland is not only an environmentally sound disposal option, but it also buffers gross value added losses in case domestic recycling (and thus glass-packaging production in Switzerland) ceases in the future. The substitution of products based on raw materials other than Swiss cullet is the main responsible for change in environmental and economic impacts. Hence, an eco-efficiency maximizing policy should consider the products of disposal schemes. The combination of scenario analysis and eco-efficiency assessment as presented in this paper can be applied to other contexts (i.e., countries, waste fractions).  相似文献   
67.
本文介绍了基于任务成功率的装备综合保障工作体系框架,提出了可靠性、维修性、测试性、保障性、安全性协同设计环境要求,从而为进行可靠性、维修性、测试性、保障性、安全性综合优化设计奠定基础。  相似文献   
68.
Watershed analysis and watershed management are developing as tools of integrated ecological and economic study. They also assist decision-making at the regional scale. The new technology and thinking offered by the advent of the Internet and the World Wide Web is highly complementary to some of the goals of watershed analysis. Services delivered by the Web are open, interactive, fast, spatially distributed, hierarchical and flexible. The Web offers the ability to display information creatively, to interact with that information and to change and modify it remotely. In this way the Internet provides a much-needed opportunity to deliver scientific findings and information to stakeholders and to link stakeholders together providing for collective decision-making. The benefits fall into two major categories: methodological and educational. Methodologically the approach furthers the watershed management concept, offering an avenue for practical implementation of watershed management principles. For educational purposes the Web is a source of data and insight serving a variety of needs at all levels. We use the Patuxent River case study to illustrate the web-based approach to watershed management. A watershed scale simulation model is built for the Patuxent area and it serves as a core for watershed management design based on web applications. It integrates the knowledge available for the Patuxent area in a comprehensive and systematic format, and provides a conceptual basis for understanding the performance of the watershed as a system. Moreover, the extensive data collection and conceptualisation required within the framework of the modeling effort stimulates close contact with the environmental management community. This is further enhanced by offering access to the modeling results and the data sets over the Web. Additional web applications and links are provided to increase awareness and involvement of stakeholders in the watershed management process. We argue that it is not the amount and quality of information that is crucial for the success of watershed management, but how well the information is disseminated, shared and used by the stakeholders. In this respect the Web offers a wealth of opportunities for the decision-making process, but still to be answered are the questions at what scale and how widely will the Web be accepted as a management tool, and how can watershed management benefit from web applications.  相似文献   
69.
基于支持向量机的湖泊生态系统健康评价研究   总被引:7,自引:4,他引:3  
利用支持向量机在处理分类问题、小样本问题和泛化推广方面的优势,构建了基于支持向量机的湖泊生态系统健康评价模型.同时,对广州市最大的人工湖——白云湖的水质及生物群落情况进行了监测,最后运用该模型对白云湖生态系统健康状况进行了评价.评价结果表明,白云湖生态系统处于病态状态,不能达到其净化水质的设计作用.建议从提高进水水质、实施湖区截污和丰富生物量3方面改善白云湖生态系统健康水平.与传统熵权综合健康指数法和熵权模糊综合评价法相比,所建模型更加客观、科学地评价了湖泊生态系统健康状况,能够为湖泊生态系统健康管理提供一定依据,具有广阔的应用前景.  相似文献   
70.
目的研制开发"海军航空装备保障统筹图绘制系统",实现海军航空装备保障管理智能化,有效利用保障资源,提高保障工作效率。方法采用C/S和B/S模式相结合,前台以NevronNETVision为系统开发平台,后台数据管理采用大型关系型数据库SQLServe,通过网络计划技术和AOE网分析技术,实现图形绘制和确定关键路线。结果通过导入Excel工作薄,实现统筹图、甘特图、资源载荷图的自动生成,提供可视化的图形编辑和统筹图的规范性检查,能进行关键路径、时间参数计算和人员负荷分析。结论 "海军航空装备保障统筹图绘制系统"智能、高效,为海军航空装备保障管理智能化提供了技术支持。  相似文献   
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