全文获取类型
收费全文 | 116篇 |
免费 | 3篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 1篇 |
环保管理 | 16篇 |
综合类 | 52篇 |
基础理论 | 17篇 |
污染及防治 | 43篇 |
评价与监测 | 10篇 |
社会与环境 | 7篇 |
出版年
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 5篇 |
2014年 | 2篇 |
2013年 | 5篇 |
2012年 | 8篇 |
2011年 | 15篇 |
2010年 | 3篇 |
2009年 | 13篇 |
2008年 | 13篇 |
2007年 | 10篇 |
2006年 | 6篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1998年 | 1篇 |
1997年 | 4篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1987年 | 1篇 |
排序方式: 共有146条查询结果,搜索用时 125 毫秒
101.
Distribution and sources of polycyclic aromatic hydrocarbons in Wuhan section of the Yangtze River, China 总被引:9,自引:0,他引:9
Polycyclic aromatic hydrocarbons (PAHs) are important organic contaminants with great significance for China, where coal burning
is the main source of energy. In this study, concentrations, distribution between different phases, possible sources and eco-toxicological
effect of PAHs of the Yangtze River were assessed. PAHs in water, suspended particulate matters (SPM) and sediment samples
at seven main river sites, 23 tributary and lake sites of the Yangtze River at the Wuhan section were analyzed. The total
concentrations of PAHs in the studied area ranged from 0.242 to 6.235 μg/l in waters and from 31 to 4,812 μg/kg in sediment.
The average concentration of PAHs in SPM was 4,677 μg/kg, higher than that in sediment. Benzo(a)pyrene was detected only at
two stations, but the concentrations were above drinking water standard. The PAHs level of the Yangtze River was similar to
that of some other rivers in China but higher than some rivers in foreign countries. There existed a positive relationship
between PAHs concentrations and the TOC contents in sediment. The ratio of specific PAHs indicated that PAHs mainly came from
combustion process, such as coal and wood burning. PAHs may cause potential toxic effect but will not cause acute biological
effects in sedimentary environment of the Wuhan section of the Yangtze River. 相似文献
102.
Precipitation Chemistry and Occurrence of Acid Rain Over Dhanbad, Coal City of India 总被引:1,自引:0,他引:1
Singh AK Mondal GC Kumar S Singh KK Kamal KP Sinha A 《Environmental monitoring and assessment》2007,125(1-3):99-110
The present study investigated the chemical composition of wet atmospheric precipitation over Dhanbad, coal city of India.
The precipitation samples were collected on event basis for three years (July 2003 to October 2005) at Central Mining Research
Institute. The precipitation samples were analyzed for pH, conductivity, major anions (F, Cl, NO3, SO4) and cations (Ca, Mg, Na, K, NH4). The pH value varied from 4.01 to 6.92 (avg. 5.37) indicating acidic to alkaline nature of rainwater. The pH of the rainwater
was found well above the reference pH (5.6), showing alkalinity during the non-monsoon and early phase of monsoon, but during
the late phase of monsoon, pH tendency was towards acidity (<5.6~pH) indicating the non-availability of proper neutralizer
for acidic ions. The observed acidic events at this site were 91, (n = 162) accounting 56% for the entire monitoring months. The (NO3 + Cl)/SO4 ratio in majority of samples was found below 1.0, indicating that the acidity is greatly influenced by SO4. The calculated ratio of (Ca + NH4)/(NO3 + SO4) ranges between 0.42–5.13 (average 1.14), however in most of the samples, the ratio is greater than unity (>1.0) indicating
that Ca and NH4 play an important role in neutralization of acidic ions in rainwater. Ca and SO4 dominate the bulk ionic deposition and these two ions along with NH4 accounts 63% of the annual ionic deposition. 相似文献
103.
The marine environment of Mumbai and Jawaharlal Nehru ports was monitored for some environmental and biological parameters
during three different periods between 2001 and 2002. The results are compared with the records available since 1960s. With
the passage of time the environmental status underwent changes, probably due to the increase in anthropogenic activities in
the metropolis. The nutrient level especially the nitrate concentration has increased gradually over the years with a simultaneous
decrease in dissolved oxygen, indicating increase in the biological activity. Characterization of this environment based on
Assessment of Estuarine Trophic Status (ASSETS) model indicates that the current status is poor and may get worsen in future
if no appropriate management policies are put into place. 相似文献
104.
Myller S. Tonhá Daniel F. Araújo Rafael Araújo Bruno C.A. Cunh Wilson Machado Joelma F. Portel João PR Souz Hikari K. Carvalho Elton L. Dantas Henrique L. Roig Patrick Seyler Jeremie Garnier 《环境科学学报(英文版)》2021,33(3):313-325
The Paraiba do Sul (PSR) and Guandu Rivers (GR) water diversion system (120 km long) is located in the main industrial pole of Brazil and supplies drinking water for 9.4 million people in the metropolitan region of Rio de Janeiro. This study aims to discern the trace metals dynamics in this complex aquatic system. We used a combined approach of geochemical tools such as geochemical partitioning, Zn isotopes signatures, and multivariate statistics. Zinc and Pb concentrations in Suspended Particulate Matter (SPM) and sediments were considerably higher in some sites. The sediment partition of As, Cr, and Cu revealed the residual fraction (F4) as the main fraction for these elements, indicating low mobility. Zinc and Pb were mostly associated with the exchangeable/carbonate (F1) and the reducible (F2) fractions, respectively, implying a higher susceptibility of these elements to being released from sediments. Zinc isotopic compositions of sediments and SPM fell in a binary mixing source process between lithogenic (δ66/64ZnJMC ≈ + 0.30‰) and anthropogenic (δ66/64ZnJMC ≈ + 0.15‰) end members. The lighter δ66/64ZnJMC values accompanied by high Zn concentrations in exchangeable/carbonate fraction (ZnF1) enable the tracking of Zn anthropogenic sources in the studied rivers. Overall, the results indicated that Hg, Pb, and Zn had a dominant anthropogenic origin linked to the industrial activities, while As, Cr, and Cu were mainly associated with lithogenic sources. This work demonstrates how integrating geochemical tools is valuable for assessing geochemical processes and mixing source effects in anthropized river watersheds. 相似文献
105.
Identifying and quantifying the contributions of multiple sources of trace elements to stream sediments in a basin containing several possible inputs presents a unique problem related to the investigation of rivers impacted by industrial activity. A multi-source dilution-mixing model was developed and applied to determine the relative contributions to As, Cu and Pb burdens in the Clark Fork River, Montana, a recipient of historical mine wastes as a result of over a century of mining and milling operations. The results identified the Flint Creek drainage as a major source of anthropogenic As (47%) and Pb (35%) to sediments of the Clark Fork River and the Milltown Reservoir, in addition to the major sources associated with mining operations in Butte, MT. The Little Blackfoot River also contributes anthropogenic As (3%) and Pb (4%) to the Clark Fork River, while minor inputs of Cu (1%) and Pb (2%) emanate from the Blackfoot River. The model allows source quantification, and an understanding of the fate and transport of mine wastes in a basin, allowing identification and eventual prioritization of sites destined for remediation. 相似文献
106.
Tait Chirenje L. Q. Ma A. G. Hornsby K. Portier W. Harris S. Latimer 《Environmental Forensics》2013,14(2):141-153
Knowledge of arsenic background concentrations in urban soils is important for making remediation decisions. The soil cleanup target level (SCTL) for arsenic in Florida lies within the range of arsenic background concentrations. The residential SCTL is also near the practical quantification limits using analytical procedures. Currently no standard protocols are available for determining arsenic background concentrations in urban soils, apart from site-specific cases. Therefore, a pilot study was conducted to develop and employ appropriate protocols to determine arsenic distribution in urban soils. This involved: site selection (e.g. size and sampling frame), sample collection (e.g. sampling technique), and statistical considerations (e.g. design). Factors such as ease of sample collection and maintaining anonymity of private properties were also considered as they influence the successful implementation of the study. Forty surface soil samples each were collected from five categories in three land use classes (residential-yard and right-of-way, commercial and public land-parks and public building), digested using EPA method 3051a and analysed using graphite furnace atomic absorption spectrometry. Experiences from the pilot study (e.g. complications during sample selection, digestion, data censoring etc.) were used in the development of the final protocol to be used in determining the distribution of arsenic in urban areas. 相似文献
107.
Soil investigations near a former smelter have revealed that historic use of arsenical pesticides has contributed significantly to anthropogenic background concentrations of arsenic on certain residential properties in Denver, Colorado, U.S.A. Remedial investigation data, based on samples collected in relatively undisturbed locations, had previously indicated that the "upper limit" of background arsenic concentrations was 28 mg/kg in the site vicinity. This value compares reasonably well with more regional data, which indicate increasing arsenic concentrations moving from rural to urban land use. Soil sampling during cleanup, however, revealed the presence of arsenic concentrations of a few hundred to more than 1000 mg/kg on a large number of residential lawns due to historic applications of a crabgrass killer, which was missed by the earlier investigation samples because of the sampling bias toward undisturbed land. Data from over 20,000 soil samples now show that several different populations comprise urban background levels of arsenic and that these populations may be stratified by land use and have spatial patterns that should be considered during any background study. A variety of forensic techniques, including spatial analysis, arsenic speciation, and calculation of metals ratios were necessary to separate the smelter impacts from pesticide impacts. 相似文献
108.
Alvyn P. Berg Ting-An Fang Hao L. Tang 《Frontiers of Environmental Science & Engineering》2019,13(1):10
109.
The concentration and loading distribution of trace metals (Cu, Zn, Pb, Co, Ni, Cr, and Mn) and major elements (Al, Ca, Fe, and Mg) in different particle size fractions (2000-280, 280-100, 100-50, 50-10, 10-2, and <2 μm) of surface soils from highly urbanized areas in Hong Kong were studied. The enrichment of Pb, Cu, and Zn in the urban soils was strongly influenced by anthropogenic activities, and Pb accumulated in fine particles was mainly derived from past vehicular emissions as shown by Pb isotopic signatures. Trace metals primarily accumulated in clay, fine silt, and very fine sand fractions, and might pose potential health risks via the inhalation of resuspended soil particles in the air (PM10 or PM2.5), and ingestion of adhered soils through the hand-to-mouth pathway. The mobility, bioavailability, and human bioaccessibility of Pb and Zn in bulk soils correlated significantly with metal concentrations in fine silt and/or very fine sand fractions. 相似文献
110.
U.C. Kulshrestha L.A.K. Reddy J. Satyanarayana Monika J. Kulshrestha 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):5123-5127
Real-time simultaneous studies on chemical characteristics of rainwater and PM10 aerosols were carried out to understand the scavenging of major chemical components in Indian region. The concentrations of Ca2+, NH4+, SO42− and NO3− were observed to be lower in the aerosol samples collected during rain as compared to before and after rain events. The most significant reduction was noticed for Ca2+ (74%) during rain which showed highest scavenging ratio (SR) and indicated that below-cloud scavenging is an effective removal process for Ca2+ in Indian region. Among non-sea salt components, Ca2+ had highest SR at Hyderabad indicating typical characteristics of crustal influence as abundance of calcium carbonate in soil dust has been reported in India. However, the levels of these major chemical components gradually got build-up in due course of time. After rain events, the levels of SO42− aerosols were noticed to be substantially higher (more than double) within 24 h. In general, scavenging ratios for all components (except Ca2+, NH4+ and K+) were higher over BOB as compared to Hyderabad. The maximum fall in aerosol levels (BR minus AR) was observed during continuous and low intensity rain events that did not allow building up of aerosol concentrations. 相似文献