全文获取类型
收费全文 | 1438篇 |
免费 | 113篇 |
国内免费 | 728篇 |
专业分类
安全科学 | 126篇 |
废物处理 | 63篇 |
环保管理 | 122篇 |
综合类 | 1074篇 |
基础理论 | 247篇 |
污染及防治 | 417篇 |
评价与监测 | 88篇 |
社会与环境 | 75篇 |
灾害及防治 | 67篇 |
出版年
2024年 | 11篇 |
2023年 | 38篇 |
2022年 | 97篇 |
2021年 | 95篇 |
2020年 | 92篇 |
2019年 | 79篇 |
2018年 | 72篇 |
2017年 | 85篇 |
2016年 | 98篇 |
2015年 | 98篇 |
2014年 | 118篇 |
2013年 | 114篇 |
2012年 | 132篇 |
2011年 | 117篇 |
2010年 | 125篇 |
2009年 | 123篇 |
2008年 | 118篇 |
2007年 | 94篇 |
2006年 | 102篇 |
2005年 | 49篇 |
2004年 | 44篇 |
2003年 | 46篇 |
2002年 | 44篇 |
2001年 | 40篇 |
2000年 | 49篇 |
1999年 | 50篇 |
1998年 | 30篇 |
1997年 | 24篇 |
1996年 | 16篇 |
1995年 | 17篇 |
1994年 | 12篇 |
1993年 | 13篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1970年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1961年 | 1篇 |
1959年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有2279条查询结果,搜索用时 9 毫秒
961.
962.
采用污泥活性炭(SAC)、TiO2/SAC、Fe3O4/SAC作为敏化剂,结合微波处理技术对污泥进行了预处理,通过分析滤液中COD、DNA、氮、磷、有机物的含量及组分,探索微波+敏化剂的最佳处理条件.SAC负载TiO2和Fe3O4后强化了其对电磁波的介电损耗和磁滞损耗,tan δε分别增加了1.8和1.3倍,tan δμ分别增加到0.26和0.67.TiO2/SAC投加量为0.25g/gSS时,样品滤液的COD浓度是1900mg/L,是原污泥和单独微波处理的4.52倍和1.86倍;Fe3O4/SAC投加量为0.35g/gSS时,样品滤液的COD浓度是2540mg/L,是原污泥和单独微波处理的6.05倍和2.45倍,Fe3O4/SAC强化污泥破壁效果更好.此时,样品滤液中TN、TP、蛋白质、多糖浓度分别为原污泥的7.7倍、16倍、7.49倍和71.69倍,微生物胞内和胞外聚合物中的物质大量释放,滤液中的溶解性有机物大大增加.微波+敏化剂的预处理方法有利于对污泥中氮、磷及有机物进行资源化利用与回收. 相似文献
963.
Ji Young Song 《International journal of occupational safety and ergonomics》2019,25(4):575-582
Purpose. The main objective of this study was to ascertain whether injury-related hospital admission in all South Korea female firefighters is greater than that in the general population. Methods. To perform this comparison, the standardized admission ratios (SARs) and their 95% confidence intervals (CIs) were calculated by person-years and mortality computation software. Results. Compared to the general population, the SARs for overall injury (SAR?=?1.57, 95% CI [1.24, 1.96]) and for injury to the lower back (SAR?=?2.78, 95% CI [1.81, 4.07]) in the female firefighters were significantly higher. The SARs for injury to the knee (SAR?=?2.48, 95% CI [1.18, 4.55]) in emergency medical services (EMS) workers were significantly higher than those in the general population. Conclusions. Our study shows that the SARs of overall injury and injury to the lower back in female firefighters and knee injury in the EMS were significantly higher than those in the general population. Further studies are needed to protect the lower back of firefighters and the knees of EMS. 相似文献
964.
Tingting Yue Fahe Chai Jingnan Hu Ming Ji Xiaofeng Bao Zhenhua Li Liqang He Lei Zu 《环境科学学报(英文版)》2016,28(10):193-199
The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas(CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0–10 km/hr were increased to 10–20 km/hr, the CO_2, CO, nitrogen oxide(NO_x), and total hydrocarbon(THC) emission factors decreased by(71.6 ± 4.3)%,(65.6 ± 9.5)%,(64.9 ± 9.2)% and(67.8 ± 0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards(Euro Ⅳ) did not have lower emission factors than the Chongqing coaches with Euro Ⅱ emission standards. Both the higher emission factors at 0–10 km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO_2 and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most(by 83.2%), followed by the THC emission factors, which decreased by 67.1%. 相似文献
965.
966.
967.
This paper examines a transition of environmental governance in China that involves increased transparency and public participation. It pays close attention to the role of the mass media in this transformation. After briefly reviewing the history of environmental governance in China, the paper examines the particular transformations in the governance regime that are associated with the controversy over the sealing of the eastern lake in the Old Summer Palace, Beijing. The paper argues that the central government has increasingly enlisted the support of the public and the media in governing environmental matters and provides evidence that the traditional mass media and the Internet have become increasingly active in environmental debates in China. 相似文献
968.
Experimental results indicated that ozone transfer in the rotating packed contactor was noticeably greater than in a traditional packed-bed contactor under similar operational conditions. Ozonation in the rotating packed contactor has been shown to be feasible for achieving nearly complete decomposition of o-cresol within 1 hour. The decomposition of o-cresol by ozonation in the rotating packed contactor increased with increasing rotor speed and decreasing the gas-liquid flowrate ratio. However, the reduction of total organic carbon during the ozonation of o-cresol was not influenced by variation of rotor speed and gas-liquid flowrate ratio. The species distribution of o-cresol under various solution conditions plays a significant role in determining the decomposition behavior. In most experiments conducted in this study, the decomposition of o-cresol by ozonation was more favorable under alkaline conditions. 相似文献
969.
970.
王继斌 《中国环境管理干部学院学报》2001,(Z1)
党的十五大把环境保护问题作为基本国策,并强调:“正确处理经济发展同人口、资源、环境的关系”。这表明生态问题已经引起高度重视,建立和发展生态工业已成为当前一项重要任务。本文在介绍生态工业定义的基础上,说明了建立和发展生态工业的必要性及其如何建立和发展生态工业。 相似文献