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   110篇
  免费   0篇
  国内免费   4篇
安全科学   8篇
废物处理   3篇
环保管理   7篇
综合类   8篇
基础理论   22篇
污染及防治   42篇
评价与监测   13篇
社会与环境   11篇
  2023年   2篇
  2021年   1篇
  2019年   4篇
  2018年   1篇
  2017年   7篇
  2016年   6篇
  2015年   3篇
  2014年   4篇
  2013年   16篇
  2012年   7篇
  2011年   6篇
  2010年   4篇
  2009年   4篇
  2008年   9篇
  2007年   4篇
  2006年   11篇
  2005年   3篇
  2004年   4篇
  2003年   6篇
  2002年   1篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1997年   1篇
  1994年   2篇
  1993年   1篇
  1991年   1篇
  1987年   2篇
  1981年   1篇
排序方式: 共有114条查询结果,搜索用时 31 毫秒
91.
In this study, seasonal observations of radon concentration changes inside buildings carried out in the northeastern region of Poland is presented. One-year measurements of radon concentrations were performed in chosen buildings. The integral method of Cr-39 trace detectors in diffusive chambers was used. Mean values of radon concentrations were determined in monthly, 2-, 3-, 6-month, and annual observations. The fraction of a mean annual concentration of the value obtained in a shorter observation was calculated. Monthly concentration values were from about 0.2 to 14.9 of the annual mean. All buildings revealed seasonal fluctuation of radon concentration. Negative correlation of indoor radon concentration in the buildings and the mean temperature outside was observed in most examined buildings. The lowest coefficient range, determining which part of the annual mean value would be obtained in the 6-month observation, was gained for exposure begun in April or October.  相似文献   
92.
Environmental Science and Pollution Research - Phytoremediation, as a cost-effective, highly efficient, environmentally friendly, and green approach, gained attention to the removal of metals,...  相似文献   
93.
Heavy metals, including cadmium (Cd), lead (Pb) and mercury (Hg) act as nephrotoxic agents, particularly in the renal cortex. The aim of the study was to determine the concentrations of Cd, Pb and Hg in kidneys removed from patients due to lesions of various etiologies and from patients after the rejection of transplanted kidneys. Additionally, we determined the influence of selected biological and environmental factors on the concentrations of toxic metals. The study material consisted of kidneys with tumor lesions (n = 27), without tumors (n = 7) and its extracted grafts (n = 10) obtained from patients belongs to the north-western areas of Poland. The determined metal concentrations in the renal cortex and medulla may be arranged in the following descending order: Cd > Pb > Hg. The highest concentrations of Cd and Hg were found in the cortex, while the maximum content Pb was observed in the medulla. Significant correlations were found in the concentrations of the same metals between cortex and medulla and between Pb and Hg in the renal medulla. Pb content was higher in the renal medulla of men than in the cortex of the elderly (above 60 years of age). The highest concentrations of Pb and Hg were found in the cortex and medulla, of the kidneys had not neoplastic changes, and lower content of these metals were found in the extracted kidney grafts. In summary, renal grafts accumulate less heavy metals than cancerous kidneys, what could have been caused by immunosuppressors taken by the graft recipients. Moreover, sex, age and smoking are key factors responsible for xenobiotics concentrations.  相似文献   
94.
Harbor sediments containing large deposits of organotin compounds constitute a potential threat to the marine environment. Samples of harbor sediments were collected twice in the years 2003 and 2005 from the following locations: Zió?kowskiego, Siarkowe, Wi?lane, Weglowe, Chemików and Paliw P?ynnych Quays. The cores of 25cm length sliced into 2- and 5-cm segments were analyzed. After drying and homogenization, samples were split into two granulometric fractions, i.e. <2.00 and <0.063mm. The dominant fraction in whole sediment, i.e. fraction grain diameter <2.00mm, was sand (grain diameter 2.00-0.063mm). However, the highest concentrations of butyltin (BT) and phenyltin (PT) compounds were found in the fine sediment fraction. The mean values of tributyltin (TBT), dibutyltin (DBT) and monobutyltin (MBT) in the analyzed samples in the <2.00mm fraction were 2144.9, 434.7 and 148.1ngSng(-1)d.w., respectively, while the corresponding mean values in the <0.063mm fraction were 6556.4, 1593.7 and 450.0ngSng(-1)d.w. The mean concentrations of monophenyltin (MPhT) have been estimated at 29.0 and 49.9ngSng(-1)d.w. for the <2.00 and <0.063mm fraction sizes, respectively. The estimated content levels of diphenyltin (DPhT) and triphenyltin (TPhT) were in most cases below the detection limit of the applied method. The sediment cores collected from the locations characterized by high industrialization and intense exploitation (Wi?lane, Weglowe Quays) contained the highest concentrations of BT and PT.  相似文献   
95.
Livestock operations are associated with emissions of odor, gases, and particulate matter. The majority of previous livestock odor studies focused on swine operations whereas relatively few relate to dairy cattle. Identifying the compounds responsible for the primary odor impact is a demanding analytical challenge because many critical odor components are frequently present at very low concentrations within a complex matrix of numerous insignificant volatiles. The objective of this study was to describe a chemical-sensory profile of dairy manure odor using headspace solid-phase microextraction (HS-SPME) and multidimensional gas chromatography-mass spectrometry-olfactometry (MDGC-MS-O). Two analytical approaches were used: (1) HS-SPME time-series extractions (from seconds up to 20 hr) followed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O) analyses, and (2) relatively short HS-SPME extractions (30 min) followed by MDGC-MS-O analyses on selected chromatogram heart-cuts. Dairy manure was collected at research dairy farms in the United States and Israel. Volatile organic compounds (VOCs) resolved from multiple analyses included sulfur-containing compounds, volatile fatty acids, ketones, esters, and phenol/indole derivatives. A total of 86 potential odorants were identified. Of them, 17 compounds were detected by the human nose only. A greater number of VOCs and odorous compounds were detected, as well as higher mass loading, on solid-phase microextraction (SPME) fibers observed for longer extractions with SPME. However, besides sulfur-containing compounds, other selected compounds showed no apparent competition and displacement on the SPME fiber. The use of MDGC-MS-O increased chromatographic resolution even at relatively short extractions and revealed 22 additional odorants in one of the regions of the chromatogram. The two analytical approaches were found to be parallel to some extent whereas MDGC-MS-O can also be considered as a complementary approach by resolving more detailed chemical-sensory odor profiles.  相似文献   
96.
This paper attempts to determine whether and to what extent forest birds take the risk of feeding in an open area in winter. In each of three plots the extra food (lard) was initially placed on the border of the forest and open area and then moved into the open area and located within 15, 30 and 45 m from the edge of the forest. Only in one plot the total number of all the birds feeding on lard significantly decreased along with the food being moved away from the edge of the forest. In other plot the number of the most numerous Great Tit Parus major and Blue Tit Cyanistes caeruleus significantly increased along with the food source being moved away into open area. The numbers of the other 7 species of birds fell or did not have directional nature. Only in one plot the aggregation (the number of individuals of a given species feeding simultaneously) increased significantly along with moving the food into open area. In other plots differences in aggregation did not have the directional nature and, in most cases, were not significant.  相似文献   
97.
Bisphenol A (BPA; 4-[2-(4-hydroxyphenyl)propan-2-yl]phenol) is a substance typically used in the plastic industry. It is used in the production of epoxy resins, polycarbonate, or fire retardants or as a stabilizer and an antioxidant in numerous types of plastics. Bisphenol A is introduced into the environment via municipal and industrial wastewater. Because of its hydrophobic properties, BPA has the potential for sorption on activated sludge during the biological wastewater treatment processes. This study investigated the degradation of BPA by means of UV-radiation and in the UV/H2O2 process with the presence and absence of hydrocarbonate ions (HCO3(-)) as hydroxyl radicals (OH*) scavengers. The calculated value of quantum yield was equal to 0.18, and the value of BPA rate constant with hydroxyl radicals was equal to 3.3 x 10(9) M(-1) s(-1).  相似文献   
98.
The paper presents water-quality evaluation based on an 8-year monitoring programme in the Gdansk Municipality region, on the Southern coast of the Baltic Sea. The studies were carried out from 2000 to 2007 by surface water analysis at 15 various sites within eight watercourses. Sampling sites included rather urbanized or developed lands, farming fields and non-polluted city recreational areas such as parks and forests. Most of the watercourses were sampled monthly at two locations, one within the upper course of the watercourse and the other near its mouth. In all samples, eight parameters of water quality were determined: total suspended solids, dissolved oxygen, water temperature, oxygen saturation, 5-day biochemical oxygen demand, chemical oxygen demand, total phosphorus and total nitrogen concentration. Interpretation of the obtained results revealed that examination of those basic physicochemical parameters permits to discriminate initially watercourses with respect to level of water contamination. During the research, a large dataset was obtained and it was described by both basic statistical parameters and chemometric method of cluster analysis. The paper presents relations between analysed parameters and influence of land exploitation mode on water quality and describes variation of the results both in space and time.  相似文献   
99.
Cyanide toxicity and their environmental impact are well known. Nevertheless, they are still used in the mining, galvanic and chemical industries. As a result of industrial activities, cyanides are released in various forms to all elements of the environment. In a natural environment, cyanide exists as cyanogenic glycosides in plants seeds. Too much consumption can cause unpleasant side effects. However, environmental tobacco smoke (ETS) is the most common source of cyanide. Live organisms have the ability to convert cyanide into less toxic compounds excreted with physiological fluids. The aim of this paper is to review the current state of knowledge on the behaviour of cyanide in the environment and its impact on the health and human life.  相似文献   
100.
Polyacrylamide(PAM) used in sludge dewatering exists widely in high-solid anaerobic digestion. Acrylamide is registered in the list of chemicals demonstrating toxic, carcinogenic and mutagenic properties. Therefore, it is reasonable to ask about the mobility of such residual substances in the environment. The study was carried out to assess the impact of the mesophilic(39 ± 1°C) and thermophilic(54 ± 1°C) fermentation process on the level of acrylamide monomer(AMD) content in the dairy sludge. The material was analysed using high-performance liquid chromatography(HPLC) for quantification of AMD. The results indicate that the process of methane fermentation continues regardless of the temperature effects on the degradation of AMD in dairy sludge. The degree of reduction of acrylamide monomer for thermophilic fermentation is 100%, while for mesophilic fermentation it is91%. In practice, this means that biogas technology eliminates the risk of AMD migration to plant tissue. Moreover, it should be stressed that 90% of cumulative biogas and methane production was reached one week earlier under thermophilic conditions — the dynamics of the methanisation process were over 20% faster.  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