全文获取类型
收费全文 | 13042篇 |
免费 | 1825篇 |
国内免费 | 975篇 |
专业分类
安全科学 | 2810篇 |
废物处理 | 278篇 |
环保管理 | 2190篇 |
综合类 | 6589篇 |
基础理论 | 1080篇 |
污染及防治 | 736篇 |
评价与监测 | 774篇 |
社会与环境 | 745篇 |
灾害及防治 | 640篇 |
出版年
2023年 | 148篇 |
2022年 | 281篇 |
2021年 | 384篇 |
2020年 | 466篇 |
2019年 | 285篇 |
2018年 | 258篇 |
2017年 | 429篇 |
2016年 | 440篇 |
2015年 | 508篇 |
2014年 | 606篇 |
2013年 | 757篇 |
2012年 | 1011篇 |
2011年 | 1095篇 |
2010年 | 803篇 |
2009年 | 807篇 |
2008年 | 563篇 |
2007年 | 893篇 |
2006年 | 915篇 |
2005年 | 708篇 |
2004年 | 641篇 |
2003年 | 608篇 |
2002年 | 535篇 |
2001年 | 386篇 |
2000年 | 401篇 |
1999年 | 361篇 |
1998年 | 242篇 |
1997年 | 226篇 |
1996年 | 182篇 |
1995年 | 196篇 |
1994年 | 154篇 |
1993年 | 121篇 |
1992年 | 97篇 |
1991年 | 55篇 |
1990年 | 40篇 |
1989年 | 23篇 |
1988年 | 14篇 |
1987年 | 16篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 16篇 |
1981年 | 9篇 |
1980年 | 19篇 |
1979年 | 14篇 |
1978年 | 16篇 |
1977年 | 9篇 |
1973年 | 7篇 |
1972年 | 9篇 |
1971年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 26 毫秒
1.
环境规制对资源型城市绿色全要素生产率是否具有推动作用,通过何种路径驱动以及是否存在城市类型异质性有待进一步理清。本文选取2004—2019年中国113座资源型城市的面板数据,利用非径向、非角度的SBM模型与GML指数对资源型城市绿色全要素生产率进行测算,随后通过构建多重中介效应模型实证检验了科技创新、外商直接投资和产业结构优化在环境规制影响绿色全要素生产率的传导机制及其在城市类型间的异质性。研究表明:(1)从全样本回归结果看,环境规制对资源型城市绿色全要素生产率的作用系数显著为正,产业结构优化和外商直接投资均发挥了显著的正向中介效应,而科技创新表现为间接抑制作用;在非资源型城市中,三类中介效应均不显著。(2)类型异质性检验显示,科技创新在成长型、成熟型城市中发挥了正向中介效应,在再生型城市中表现为间接抑制作用;外商直接投资在衰退型城市中的中介效应值为正,而在再生型城市中表现为负向中介效应;产业结构优化在成长型与成熟型城市中发挥了正向中介效应。(3)对比中介效应结果表明,全样本回归时,产业结构优化、外商直接投资和科技创新的中介效应梯次递减,产业结构优化的中介效应占比接近80%,环境规制的... 相似文献
2.
Jennifer M. Sanders C. Rhett Jackson Meredith Welch-Devine 《Journal of the American Water Resources Association》2023,59(4):803-823
Despite long-standing knowledge of the benefits of riparian buffers for mitigating nonpoint source pollution, many streams are unprotected by buffers. Even landowners who understand ecological values of buffers mow riparian vegetation to the streambank. Do trends in rural riparian conditions reflect the development of riparian forest science? What motivates residential riparian management actions? Using high-resolution orthoimagery, we quantified riparian conditions and trends between 1998 and 2015 in the rural upper Little Tennessee River basin in Macon County, North Carolina and explored how landowners view riparian zone management and riparian restoration programs. Buffer composition in 2015 was as follows: no buffer (32.5%), narrow (19.3%), forested (26.7%), shrub (7.2%), and intermediate (7.0%). Relative to 1998, the greatest decrease occurred in the no buffer class (−17.7%, 46 km) and the largest increases occurred in the shrub (+72.5%, 20 km) and narrow (12.6%, 14 km) classes. Forested buffer marginally increased. Semi-structured interview data suggest that landowners prioritize recreational and scenic aspects of riparian buffers over ecological functions such as filtration and bank stabilization. Riparian restoration programs might be made more enticing to non-adopters if outreach language appealed to landowner priorities, design elements demonstrated intentional management, and program managers highlighted areas where ecological goals and landowner values align. 相似文献
3.
Pankaj Kumar Vandana Mishra Saiyami Bhardwaj Shafali Garg Ludovic F. Dumée Radhey Shyam Sharma 《环境质量管理》2023,32(4):9-17
Sectorial approach for monitoring heavy metal pollution in rivers has failed to report realistic pollution status and associated ecological and human health risks. The increasing spread of heavy metals from different sources and emerging risks to human and environmental health call for reexamining heavy metal pollution monitoring frameworks. Also, the sources, spread, and load of heavy metals in the environment have changed significantly over time, requiring consequent modification in the monitoring frameworks. Therefore, studies on heavy metal monitoring in rivers conducted in the last decade were evaluated for experimental designs, research frameworks, and data presentations. Most studies (∼99%) (i) lacked inclusiveness of all environmental compartments; (ii) focused on “one pollutant – one/two compartment” or sometimes “one pollutant – one compartment – one effect” approach; and (iii) remained “data-rich but information poor.” An ecological approach with integrative system thinking is proposed to develop a holistic approach for monitoring river pollution. It is visualized that heavy metal monitoring, risk analyses, and water management must incorporate tracking pollutants in different environmental compartments of a river (water, sediment, and floodplain/bank soil) and consider correlating it with riverbank land use. The systems-based pollution monitoring and assessment studies will reveal the critical factors that drive heavy metals pollutant movement in ecosystems and associated potential risks to the environment, wildlife, and humans. Also, water quality and pollution indexing tools would help better communicate complex pollution data and associated risks among all stakeholders. Therefore, integrating systems approaches in scientific- and policy-based tools would help sustainably manage the health of rivers, wildlife, and humans. 相似文献
4.
梳理了高校实验室环境-安全-健康准入制度包含的管理内容,从人员管理、设备管理、试剂管理、实验环境管理角度进行了分析。根据现有实验室安全信息化系统运行情况,探讨了将实验室安全信息化系统与实验室信息化系统、设备管理信息化系统进行数据融合和功能优化的要点,重点分析了设备采购及管理系统、实验室安全教育与考试系统、实验室安全检查系统、试剂管理平台、实验室门禁管理系统在功能上的内在关联,从而通过试剂管理平台、实验室门禁控制系统、设备采购系统实现实验室环境-安全-健康准入制度的强制执行。研究发现,高校与环境监测实验室、院系实验室安全管理部门联合促进实验室安全信息化系统、实验室信息化系统、设备管理信息化系统的数据共享与功能升级,可以丰富实验室安全准入制度的内涵和管理手段,加强实验室安全准入制度的强制执行力,提高实验室安全管理效率。 相似文献
5.
The iron and steel industry is not only an important foundation of the national economy, but also the largest source of industrial air pollution. Due to the current status of emissions in the iron and steel industry, ultra-low pollutant emission control technology has been researched and developed. Liquid-phase proportion control technology has been developed for magnesian fluxed pellets, and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets (80%) for the first time in China to realize source emission reduction of SO2 and NOx. Based on the characteristics of high NOx concentrations and the coexistence of multiple pollutants in coke oven flue gas, low-NOx combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of sulfur. Based on the characteristics of co-existing multiple pollutants in pellet flue gas, selective non-catalytic reduction (SNCR) coupled with ozone oxidation and spray drying adsorption (SDA) was developed, which significantly reduces the operating cost of the system. In the light of the high humidity and high alkalinity in flue gas, filter materials with high humidity resistance and corrosion resistance were manufactured, and an integrated pre-charged bag dust collector device was developed, which realized ultra-low emission of fine particles and reduced filtration resistance and energy consumption in the system. Through source emission reduction, process control and end-treatment technologies, five demonstration projects were built, providing a full set of technical solutions for ultra-low emissions of dust, SO2, NOx, SO3, mercury and other pollutants, and offering technical support for the green development of the iron and steel industry. 相似文献
6.
Junhua Li Shangchao Xiong Jianjun Chen Hao Liu Wenzhe Si Yue Peng Xuecheng Wu Huan Liu 《环境科学学报(英文版)》2023,123(1):400-416
In most of the world's building material industries, the control of flue gas pollutants mainly focuses on a single pollutant. However, given the large capacity and high contribution of China's building materials industry to global air pollution, the need to develop multi-pollutant emission reduction technology is urgent. Recently, China has focused on reducing the emissions of flue gas pollutants in the building materials industry, established many key research and development projects, and gradually implemented more stringent pollutant emission limits. This project focuses on the most recent advances in flue gas emission control technology in China's building materials industry, including denitration, dust removal, desulfurization, synergistic multi-pollutant emission reduction, and the construction of pilot research and demonstration projects for pollutant removal in several building material industries. On this basis, revised pollutant limits in flue gas emitted in China's building material industry are proposed. 相似文献
7.
8.
为准确评价城轨信号系统安全保障能力及影响因素,基于云理论对定性与定量因素的良好融合优点,构建城轨信号系统安全保障能力评价云模型及评价指标体系,采用组合赋权法对各指标赋予权重,并基于专家意见,利用正向云发生器生成标准云。结果表明:该云模型具有一定稳定性和可靠性,可对城轨信号系统安全保障能力进行有效测评,同时能够发现安全运营中的缺陷,有助于协助管理方进行针对性改善,以提高城轨信号系统的安全保障能力。 相似文献
9.
为充分发挥立法的引领和推动作用,不断完善中国矿山安全法律法规体系,分析我国矿山安全领域的立法现状,借鉴美国矿山安全立法经验及启示,立足于我国矿山安全监管监察体制革新的新形势和新要求,提出了以《矿山安全法》为基本法,以行政法规、部门规章、监察手册和强制性标准为支撑的新发展阶段矿山安全法规标准体系,为中国矿山安全领域立法提供参考。 相似文献
10.
应用现代信息技术及装备,设计开发“企业+监理+承包商”三级一体化工程项目HSSE管理支撑系统,具有人员管理、培训考试、施工机具管理、风险管理、监督检查、考核奖惩等主要业务流程管理功能,同时提供专家知识库支持,有效支撑项目HSSE管理。多个项目应用结果表明,该系统满足企业、监理和承包商对项目实施一体化HSSE管理的需要,优化了各业务环节管理流程,加强了管控手段,有效解决了人员能力不足、责任不落实等问题,促进了HSSE工作的规范化、标准化、精细化、高效化,具有广阔的推广应用前景。 相似文献