全文获取类型
收费全文 | 445篇 |
免费 | 13篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 36篇 |
废物处理 | 2篇 |
环保管理 | 154篇 |
综合类 | 155篇 |
基础理论 | 48篇 |
污染及防治 | 25篇 |
评价与监测 | 23篇 |
社会与环境 | 25篇 |
灾害及防治 | 17篇 |
出版年
2023年 | 5篇 |
2022年 | 3篇 |
2021年 | 16篇 |
2020年 | 20篇 |
2019年 | 8篇 |
2018年 | 13篇 |
2017年 | 17篇 |
2016年 | 18篇 |
2015年 | 18篇 |
2014年 | 17篇 |
2013年 | 28篇 |
2012年 | 19篇 |
2011年 | 22篇 |
2010年 | 25篇 |
2009年 | 19篇 |
2008年 | 24篇 |
2007年 | 16篇 |
2006年 | 16篇 |
2005年 | 16篇 |
2004年 | 9篇 |
2003年 | 16篇 |
2002年 | 12篇 |
2001年 | 15篇 |
2000年 | 17篇 |
1999年 | 12篇 |
1998年 | 10篇 |
1997年 | 9篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1986年 | 6篇 |
1985年 | 6篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有485条查询结果,搜索用时 62 毫秒
31.
Globally, the issue of energy use and climate change is at the forefront of many national and international agendas, and also an issue central to children's lives and well-being. This paper examines how children are both affected by and contribute to the problems associated with unsustainable energy use as it relates to the growth of car dependent lives. The paper presents the findings of a study of travel as it relates to the everyday lives of children in the city of Dunedin in New Zealand. The study found that children currently lead complex car dependent lives. This extensive car reliance presents a serious and largely unrecognised challenge to the sustainable planning and management of the urban environment. The move towards more sustainable transportation can bring benefits for both the environment and for children's lives. 相似文献
32.
Foran J. Brosnan T. Connor M. Delfino J. DePinto J. Dickson K. Humphrey H. Novotny V. Smith R. Sobsey M. Stehman S. 《Environmental monitoring and assessment》2000,62(2):147-167
The International Life SciencesInstitute (ILSI) Risk Science Institute (RSI) convenedan expert panel of scientists to developrecommendations for a comprehensive monitoring programfor the Croton and Catskill/Delaware watersheds, whichprovide drinking water to New York City's residents. This effort was conducted as part of efforts topreserve and enhance the quality of New York City'sreservoir system through a watershed protectionprogram. The panel developed recommendations for astrategic framework on which to construct a monitoringprogram. As part of this activity, the paneldetermined whether existing monitoring activities weredeficient and, where activities were deficient, thepanel developed recommendations for additionalinformation that should be collected.The panel recommended the development and use of anintegrated approach to watershed monitoring, whichdraws on modeling, risk-based planning and analysis,statistical sampling and design, and basic compliancemonitoring. The approach should be designed toprovide an assessment of natural and anthropogenicsources of stress to the system as well as anassessment of water quality trends in response tostresses acting in concert, both over the long termand over the five-year New York City Memorandum ofAgreement (MOA) assessment time frame. It should alsoprovide an assessment of the human health andenvironmental risks posed by a variety of stressors,and the impact of management actions implemented toameliorate stressors. 相似文献
33.
酸沉降影响稻米品质的新发现 总被引:2,自引:0,他引:2
酸沉降影响了稻米质量和口感.酸雨时空分布从宏观上概括了稻米品质的地理分布.酸雨决定了酶活性相关金属离子的丰缺,继而影响淀粉合成关键酶的活性,最终影响淀粉合成质量.温度变化是表象,降雨pH值变化是条件,酶活性相关金属离子丰缺是根本,实质是酶活性相关金属离子或激活或抑制了支链淀粉合成关键酶的活性.提出了改善粮食作物质量的化控创新技术路线. 相似文献
34.
基于生态系统服务供需的雄安新区生态安全格局构建 总被引:2,自引:0,他引:2
生态安全格局构建是保障区域生态安全的关键。沿用“源地识别—阻力面构建—廊道提取”的生态安全格局构建模式,选取粮食供给、产水量、土壤保持、固碳释氧和生境维持5项生态系统服务供给指标,以及人口密度、地均GDP和土地利用程度3项生态系统服务需求指标,综合生态系统服务供需2方面识别重要生态源地,利用夜间灯光强度进行基本阻力面修正,采用最小累积阻力模型进行生态廊道提取,构建出雄安新区生态安全格局。研究表明:新区生态源地总面积约48433 km2,占新区土地总面积的313%,主要分布于新区西北部旱地和东南部水域;新区生态阻力系数空间分布较为破碎,大部分区域阻力值较低,间或分布高阻力值;新区生态廊道总长度18586 km,呈“Y”字型沿建设用地和水系分布,所处地类主要为旱地。基于生态系统服务供需的生态安全格局构建可为新区规划建设提供参考和借鉴。 相似文献
35.
Ali Tighnavard Balasbaneh Abdul Kadir Bin Marsono 《International Journal of Sustainable Engineering》2017,10(3):176-184
The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO2 emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO2 emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO2 emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO2 emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO2 emissions compared to other schemes. Therefore, S8 has a decreased CO2 effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing. 相似文献
36.
Parakkatt Parambil Leena Vasudevan Anil Kumar Kundan. K. Dani Sunil. M. Sombawne Palani Murugavel Govindan Pandithurai 《毒物与环境化学》2017,99(4):652-664
The formation of ultrafine particles, their growth, and associated characteristic features has been studied during new particle formation events over a high-altitude station of the Western Ghats during the 2014 post-monsoon season. Most of the events were observed during noon time where particle bursts in the nucleation-mode size range from 5 to 25 nm followed by sustained growth in size. This phenomenon persists for ~4–8 h with a growth rate of 1–2 nm h–1. Peak concentrations of nucleation-mode particles during the event generally vary from 2300 to 5000 cm–3. The mean growth rate is 1.4 ± 0.42 nm h–1, particle formation rate is 1.14 ± 0.22 cm–3 s–1, coagulation sink is 0.35 ± 0.22 cm–3 s–1, and condensational sink is 15.4 ± 2.6?×?10–3 s–1. All these values are comparable with earlier results from Indian region. Comparison of size-segregated particle number concentration during days of new particle formation events and those without new particle formation were carried out showing a distinct variation in nucleation and Aitken mode with least variability associated with the accumulation mode. 相似文献
37.
Francisca F. del Campo 《Environmental pollution (Barking, Essex : 1987)》2010,158(9):2906-108
Microcystins (MCs) are toxic cyclic heptapeptides produced by various cyanobacteria genera, especially Microcystis. We identified 10 out of 12 MCs produced by three Microcystis aeruginosa strains from cyanobacteria collections, UTEX 2666, UTEX 2670 and UAM 1303, by using two analytical methods: Matrix-assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF/MS) and HPLC Photodiode Array Detector coupled to a hybrid Quadrupole Time of Flight Mass Spectrometry (HPLC-PDA-QTOF/MS). MALDI-TOF/MS failed to detect non-polar MCs, such as MC-LY and MC-LW. HPLC-QTOF/MS permitted the accurate identification of most MCs present in methanolic extracts. Besides, three new MCs, namely: [D-Glu(OCH3)6, D-Asp3] MC-LAba, MC-YL and MC-YM were detected by HPLC-QTOF/MS. 相似文献
38.
Incidence of polybrominated diphenyl ethers in central air conditioner filter dust from a new office building 总被引:2,自引:0,他引:2
This study examined polybrominated diphenyl ethers (PBDEs) in central air conditioner filter (CACF) dust from a new office building in Shenzhen, China. Human exposure to PBDE via dust inhalation and ingestion were also estimated. PBDEs level in CACF dust was lower than those in the other countries and regions. Approximately 0.671 pg/kg bw/day PM2.5 (Particulate Matter up to 2.5 μm in size) bounded Σ15PBDEs can be inhaled deep into the lungs and 4.123 pg/kg bw/day PM10 (Particulate Matter up to 10 μm in size) bounded Σ15PBDEs tend to be deposited in the upper parts of the respiratory system. The average total intake of Σ15PBDEs via dust inhalation and ingestion for adults reached ∼141 pg/kg bw/day in this building. This value was far below the reference dose (RfD) recommended by United States Environmental Protection Agency. Human exposure to PBDEs via dust inhalation and ingestion in the new building is less than the old ones. 相似文献
39.
The use of futures in copper marketing became common during the 1990s, but little attention has been put on the reasons for it and its relationship with other elements of marketing such as forward sales and premiums. This study focuses on these issues and the benefit of futures relative to annual forward contracts. It argues futures complement annual forward contracts to secure the average market price rather than to maximize revenue. The paper analyzes empirical evidence for the six largest Chilean copper producers. This sample reflects well the entire Chilean industry during the 1990s. The analysis shows that forward sales became more volatile and futures seem to be the instrument to avoid income fluctuation at the end of the marketing process. However, the benefits of futures compared to forward sales are very modest. In the last section we suggest a better marketing instrument to maximize revenue may be premiums. 相似文献
40.
ABSTRACT: Local governments often face environmental problems that cross political boundaries. The onus for solution usually falls on the moat severely affected jurisdiction, others do nothing until impacted. Resolution of these problems requires cooperation across political boundaries which means that local governments must be persuaded first that there is a problem, and second that action is required to solve it. This paper presents a method to supply low cost, credible information that can be used to achieve consensus on problem solution. A case study of a lake water quality management problem is described. Formative evaluation techniques was adapted to provide a minimum of evidence which was then used to persuade less impacted local jurisdictions to cooperate in the problem solution. 相似文献