首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   572篇
  免费   3篇
  国内免费   6篇
安全科学   5篇
废物处理   39篇
环保管理   58篇
综合类   45篇
基础理论   134篇
污染及防治   162篇
评价与监测   110篇
社会与环境   27篇
灾害及防治   1篇
  2023年   15篇
  2022年   49篇
  2021年   32篇
  2020年   10篇
  2019年   11篇
  2018年   18篇
  2017年   15篇
  2016年   27篇
  2015年   17篇
  2014年   30篇
  2013年   56篇
  2012年   28篇
  2011年   31篇
  2010年   36篇
  2009年   22篇
  2008年   34篇
  2007年   27篇
  2006年   20篇
  2005年   14篇
  2004年   11篇
  2003年   13篇
  2002年   15篇
  2001年   7篇
  2000年   3篇
  1999年   5篇
  1998年   3篇
  1997年   1篇
  1996年   2篇
  1995年   2篇
  1994年   4篇
  1992年   4篇
  1991年   1篇
  1989年   2篇
  1984年   1篇
  1980年   1篇
  1978年   1篇
  1976年   1篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
  1969年   1篇
  1966年   1篇
  1964年   1篇
  1961年   3篇
  1960年   1篇
  1958年   1篇
  1957年   1篇
排序方式: 共有581条查询结果,搜索用时 328 毫秒
501.
Environmental Science and Pollution Research - Nanopriming is an emerging field of science which uses nanoparticles in solution to improve parameters of seed vigor. This leads to an initial...  相似文献   
502.
Environmental Science and Pollution Research - The industrial revolution has marked a strong impact on financial upgradation of several countries, and increase in the industrial establishment...  相似文献   
503.
Environmental Science and Pollution Research - Solar energy is one of the major sources of renewable energy which contributes for environmental protection and pollution reduction. Methods and...  相似文献   
504.
Life cycle assessment (LCA) provides a concept, framework, and method to identify and evaluate the environmental burdens of products and processes. An ongoing concern of companies trying to implement LCA is the value of LCA in supporting actual decisions versus the resources and time needed to conduct a “full” LCA. In response to these concerns, there has been a lot of activity surrounding the “streamlining” of LCA to keep it more manageable yet provide useful and acceptably accurate results. This article explores the concept of streamlining, discusses where and how streamlining decisions can be made in an LCA, and presents issues related to conducting more streamlined LCAs. Due to the wide variety of purposes and scenarios in which LCAs are conducted, it is difficult to devise a one-size-fits-all method for streamlining. Instead, we have focused on presenting the streamlining options in the context of major decision points that are common to most LCAs.  相似文献   
505.
The global agenda of sustainable development (SD) will get a major boost from the successful implementation of the Sustainable Development Goals (SDGs) in developing countries. This requires effective planning and understanding of the SDGs at the national level and developing sound SDG indicators that account for country priorities. Currently, there is no formal SDG indicator set in India, but the process for it is underway. This paper has attempted to propose a unique technique for identifying the most representative indicator set for SD measurement in India based on the SDGs. Considering the needs and preferences of the country, a three‐stage process is proposed to develop the priority indicator set. The application of the approach has been presented for SDG 7, which relates to energy. This is supported with a background on India's SD progress. The proposed technique is simple yet effective, and can be easily replicated by other developing countries.  相似文献   
506.
This study was conducted in the summer season (May, 2007). The fluoride concentration along with other physico-chemical parameters in ground water samples was determined in Marks Nagar of Unnao district, Uttar Pradesh (India), since it is the only source of drinking water for the villagers. The fluoride concentration in the water varied from 0.8 to 13.9 mgl−1 with a mean of 4.02 mgl−1. The correlation analysis revealed that fluoride had a positive correlation with pH, CO3, HCO3, and sodium adsorption ratio (SAR), whereas a negative correlation with Ca and Mg was found. A soil profile was also dug in the area to assess depth-wise fluoride content in the soil. The soil samples and underneath calcium carbonate (CaCO3) concretion were analyzed for fluoride content. The percent of soluble fluoride to total fluoride in the soil varied from 25.15 to 4.76% down the soil profile. The soluble fluoride was found to decrease with the increase in the clay content in the soil. The total leachable fluoride in CaCO3 concretions was found to be 6.08%. It was inferred from this study that the soil and underneath layer of CaCO3 concretions may be the potential source of fluoride contamination in the shallow drinking water sources of the area.  相似文献   
507.
The presence of dyes in water is undesirable due to the toxicological impact of their entrance into the food chain. Owing to the recalcitrant nature of dyes to biological oxidation, a tertiary treatment like adsorption is required. In the present study, unsaturated polyester resin (UPR) has been used as a sorbent in the treatment of dye-contaminated water. Different concentrations of Tropaeoline 000 containing water were treated with UPR. The preliminary investigations were carried out by batch adsorption to examine the effects of pH, adsorbate concentration, adsorbent dosage, contact time, and temperature. A plausible mechanism for the ongoing adsorption process and thermodynamic parameters have also been obtained from Langmuir and Freundlich adsorption isotherm models. Thermodynamic parameter showed that the sorption process of Tropaeoline 000 onto activated carbon (AC) and UPR were feasible, spontaneous, and endothermic under studied conditions. The estimated values for (ΔG) are ?10.48?×?103 and ?6.098?×?103 kJ mol?1 over AC and UPR at 303 K (30 °C), indicating towards a spontaneous process. The adsorption process followed pseudo-first-order model. The mass transfer property of the sorption process was studied using Lagergren pseudo-first-order kinetic models. The values of % removal and k ad for dye systems were calculated at different temperatures (303–323 K). The mechanism of the adsorption process was determined from the intraparticle diffusion model.  相似文献   
508.
Fresh water prawns, Macrobrachium lamarrei and Macrobrachium dayanum (Crustacea-Decapoda) were subjected to static bioassay tests to ascertain the LC50 values of copper sulphate. The 24, 48, 72 and 96 hr LC50 values of copper sulphate for M. lamarrei were 0.38, 0.361, 0.343 and 0.300 mg/l and for M. dayanum were 1.634, 0.988, 0.532 and 0.418 mg/l respectively. Behavioral responses and LC50 values indicate that M. lamarrei were more sensitive to copper sulphate than M. dayanum.  相似文献   
509.
A study was performed to investigate the effects of complete and skeleton photoperiods on gonadal stimulation in baya weaver, Ploceus philippinus. In August 2003, five groups of acclimatized birds (n = 7 each) were exposed to 6L: 13D: 1L: 4D, 6L: 6D: 1L: 11D, 11L: 13D and 13L: 11D. Birds were refractory and their exposure to 6L:13D:1L:4D, 6L:6D:1L:11D, 11L:13D and 13L:11D did not evoke any response. This clearly indicates that the birds were insensitive to the stimulatory effects of these photoperiods and perceived them as short days. An attempt was made to test the responsivity by subjecting all these groups to long day exposure after 16 weeks of experiment. Under 16L: 8D, birds did not show a response during the first 4 weeks of exposure (week 16 to week 20), but thereafter there was a significant photoinduction except 11L:13D (week 24), but the rate and magnitude was different. Until the end of the experiment (32 weeks), all groups of birds had maximum testicular volume except 11L:13D. Birds pre-exposed to 6L:13D:1L:4D, 6L:6D:1L:11D, 11L:13D and 13L:11D responded to 16L:8D, which suggests that these photoperiods helped the birds in recovering their photosensitivity. The results from this experiment indicate that baya weaver interprets a light period depending when the light falls relative to its endogenous circadian system.  相似文献   
510.
Thin-layer chromatography (TLC) is shown as an effective, inexpensive, reliable, and less time consuming technique for simple and effective monitoring of persistent toxicant-like DDT in its manufacturing plant effluent. Aqueous untreated and treated grab and composit effluent samples were collected, extracted with a solvent and concentrated and chromatographed both for qualitative and quantitative analysis for p, p′-DDT and related compounds. This technique was successful and can form an effective, inexpensive method to be used by the developing countries, which have limited financial resources.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号