全文获取类型
收费全文 | 274篇 |
免费 | 22篇 |
国内免费 | 125篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 7篇 |
环保管理 | 12篇 |
综合类 | 164篇 |
基础理论 | 82篇 |
污染及防治 | 127篇 |
评价与监测 | 20篇 |
社会与环境 | 5篇 |
出版年
2024年 | 1篇 |
2022年 | 5篇 |
2021年 | 3篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 13篇 |
2015年 | 13篇 |
2014年 | 18篇 |
2013年 | 44篇 |
2012年 | 52篇 |
2011年 | 46篇 |
2010年 | 24篇 |
2009年 | 18篇 |
2008年 | 18篇 |
2007年 | 22篇 |
2006年 | 11篇 |
2005年 | 7篇 |
2004年 | 14篇 |
2003年 | 11篇 |
2002年 | 14篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 6篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有421条查询结果,搜索用时 0 毫秒
381.
The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polybrominated diphenylethers (PBDEs) in 33 breast milk samples collected in 2006-2007 from primipara mothers close to four industrial areas of Slovak Republic were determined. The total PCDDs/PCDFs and dl-PCBs expressed as TEQ based on WHO TEFs 1998 in breast milk samples varied from 5.0 to 51.8 pg g−1 fat (median: 13.1 pg g−1 fat; mean: 18.0 pg g−1 fat). The measurements of seven PBDE congeners (IUPAC No. 28, 47, 99, 100, 153, 154, and 183) were performed for the first time in human milk from Slovakia. PBDE levels ranged between 0.22 and 1.62 ng g−1 fat, with median and mean value of 0.43 ng g−1 fat and 0.57 ng g−1 fat respectively. No statistically significant differences were observed between studied areas in total PBDE concentrations.Furthermore, this study presents first results concerning the daily intake (DI) of PCDDs/PCDFs and dioxin-like compounds for the most vulnerable breast-fed infant population in Slovakia. The total PCDD/PCDF and dl-PCB DI for an infant during the first 2 months of life was estimated in a range from 14.4 to 230 pg TEQ kg−1 b.w., with a median value of 58.9 pg TEQ kg−1 b.w.. The DI values substantially exceeded the tolerable daily intake (TDI) 1-4 pg TEQ kg−1 b.w. recommended by WHO. The dietary infant intake concerning PBDEs was estimated to be between 0.69 and 7.1 ng kg−1 b.w. d−1, with median value of 1.7 ng kg−1 b.w. d−1. 相似文献
382.
Agnieszka Hernik Katarzyna GóralczykPaweł Struciński Katarzyna CzajaWojciech Korcz Maria MinorczykJan Krzysztof Ludwicki 《Chemosphere》2013
The purpose of this study was to assess human exposure in the prenatal period to selected PBDEs (BDE-47, BDE-99, BDE-153) and PCBs (CB-77, CB-101, CB-118, CB-126, CB-138, CB-153, CB-170, CB-180) basing on the analysis of these compounds in cord blood. The experimental material consisted of 89 cord blood samples taken from women resident in Warsaw and its vicinity. In over 90% of all tested samples the presence of congeners CB-153, CB-138, CB-180 and BDE-47 was identified. The least frequently found were CB-126 and BDE-153, which were present at relatively low concentration levels. Among all analysed PCBs, the highest average concentrations were found in the case of congeners CB-138 (11.8 ng/g of fat) and CB-153 (43.4 ng/g of fat), whereas the lowest was in the case of CB-170 (0.4 ng/g of fat) and CB-126 (0.1 ng/g of fat). In the case of PBDEs the greatest share in the total concentration was that of the congeners BDE-47 and BDE-99, whereas the smallest share was that of the higher brominated congener BDE-153. These results suggest that human exposure to the examined compounds begins already in the period of intrauterine life. The comparison of our own results with the findings of other authors indicates that the PCBs and PBDEs levels in cord blood of women living in Poland do not differ from the respective concentrations in cord blood of other female inhabitants of Europe. 相似文献
383.
An effective method for determination of indicator polychlorinated biphenyls (PCBs) has been validated using gas chromatography (GC) equipped with electron capture detector (ECD). The GC–ECD method was validated by determining the linear range (working range) for determination of the compounds, minimum detectable quantities (MDQ), the precision and accuracy of the method for the analysis of the compounds. MDQ obtained for the compounds ranges from 0.0005 to 0.002 ng. Indeed the method was found to be more sensitive as the number of chlorine atoms attached to the biphenyl increases. The precision and accuracy of the GC method validated ranges from 2.4% to 14.5% and −7.0% to 14.6% respectively. Coefficient of variation associated with the repeatability of the retention times and corresponding peak areas was found to be 0.0001–0.0007 for the retention times and 0.0014–0.059 for the peak areas. Percentage recoveries for the compounds were in the range of 95.7–101.0%. The validated method was then applied to determine levels of indicator PCBs in sediments sampled from eleven sampling points along the Lake Bosuntwi in Ghana and the highest PCB load of 19.17 ng g−1 was recorded at Pipie No. 2. PCB 52 and PCB 101 were found to be the most ubiquitous indicator PCBs in the study area, both with 90.91% occurrence. 相似文献
384.
Municipal solid waste (MSW) source-classified collection represents an advancement in resource cycling and secondary pollution control in China. Comparative experiments were performed to assess the levels and patterns of polychlorinated biphenyls in bottom ash, fly ash from boiler, and fly ash from bag filter from an MSW incineration plant with source-classified collection of MSW. Polychlorinated biphenyls were concentrated in the bag filter fly ash and in the bottom ash. The total amount of polychlorinated biphenyls was much lower than in fly ashes and bottom ash from traditional mixed waste incineration. Total concentration of coplanar polychlorinated biphenyls and toxic equivalent quantities were also reduced. Due to variations of feed waste, complete combustion, including continuously high incineration temperature, low CO concentrations and high air excess ratio were observed. Incineration temperature showed a negative correlation, while CO concentration showed a positive correlation with total and coplanar polychlorinated biphenyls, indicating that the latter can be reduced by controlling combustion conditions related to properties of feed waste. 相似文献
385.
386.
Occurrence and congeners specific of polychlorinated biphenyls in agricultural soils from Southern Jiangsu, China 总被引:7,自引:0,他引:7
A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls (PCBs) in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% of ∑PCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% of ∑PCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs. 相似文献
387.
喀斯特峡谷区常见植物叶片δ13C值与环境因子的关系研究 总被引:1,自引:1,他引:1
通过对贵州花江峡谷喀斯特石漠化区4种典型石漠化植物群落中11种常见植物种叶片的δ13C值测定,研究了各植物种对影响植物碳同位素分馏的主要环境因子(土壤储水量、大气相对湿度、光照强度、土壤厚度)的响应,分析了石漠化梯度中不同土层土壤储水量、大气相对湿度、土壤有机质、年均气温、光照强度等环境因子梯度变化与植物叶片δ13C值的关系.结果表明,大部分物种的δ13C值对环境因子的变化趋势表现为随环境水分好转呈下降趋势,即水分利用效率下降;也有部分物种呈稳定不变或逆势上升趋势.相关性分析表明,清香木(Pistacia weinmannifolia)、石岩枫(Mallotus repandus)、红背山麻杆(Alchornea trewioides)的主导因子是土层储水量;肾蕨(Nephrolepis cordifolia)、野桐(Mallotus japonicus var.floccosus)的主导因子是土壤厚度;肾蕨、八角枫(Alangium chinense)、构树(Broussonetia papyrifera)的主导因子是光照强度;而广西密花树(Rapanea kwangsiensis)、圆叶乌桕(Sapium rotundifolium)和灰毛浆果楝(Cipadessa cinerascens)则分辨不出主导因子,即环境影响因素更为综合.总体而言,叶片高δ13C值是对低水分、高光、低资源环境的适应. 相似文献
388.
现代黄河三角洲土壤中多氯联苯来源解析研究 总被引:2,自引:2,他引:2
对现代黄河三角洲22个表层土壤样品中类二英类多氯联苯(PCBs)进行双毛细管柱GC-ECD结合MS测试,并对所得数据进行主成分分析,在同系物水平上解析了现代黄河三角洲土壤中PCBs污染的类型、来源、贡献率和同系物组成.结果表明,现代黄河三角洲土壤中PCBs污染存在4类污染源:第1类污染是由地表径流带来的非点源污染,来自黄河沿岸企业的工业生产和使用,其贡献率为49.6%,同系物组成与国产PCBs相似,且与Aroclor1221相对应;第2和第3类同属点源污染,来自沿海地区的油田开采活动,贡献率分别为15.0%和10.1%,第2类同系物组成与Aroclor1221和Aroclor1242叠加的结果类似,第3类与Aroclor1260相似;第4类污染是由大气污染导致的非点源污染,来自大气的干、湿沉降,其贡献率为8.4%,同系物组成与Aroclor1242、Aroclor1248和Aroclor1260叠加的结果类似. 相似文献
389.
珠江三角洲空气中多氯联苯污染的区域背景研究 总被引:12,自引:0,他引:12
选择肇庆市鼎湖山自然保护区作为珠江三角洲地区大气中多氯联苯(PCBs)污染评价的区域性环境背景.研究表明,背景区夏季空气中PCBs的平均浓度为216.94pg/m3,其中气态PCBs的浓度是183.42pg/m3,是颗粒态的5.47倍;PCBs总量的氯数分布以三氯和四氯取代的PCBs为主,两者的总贡献率为86.41%.冬季空气样品中PCBs的总浓度是176.43pg/m3,其中气相中的浓度为123.20pg/m3,仅是颗粒相中浓度的2.31倍.与夏季空气样品不同的是,冬季气相样品中二氯到四氯取代的PCBs浓度仅是颗粒相样品中的2.94倍,几乎是夏季的1/2.与国外研究相比,鼎湖山自然保护区空气中PCBs的浓度很高. 相似文献
390.
A. Watanabe A. Ohara N. Tajima S. Yoneki Y. Hosoya 《Journal of Material Cycles and Waste Management》2003,5(1):0039-0048
Polychlorinated biphenyls (PCBs), a type of persistent organic pollutants (POPs), are considered to be endocrine disrupters.
According to the Stockholm Convention on POPs, PCB detoxification is being accelerated globally. We have developed an environmentally
sound chemical PCB detoxification plant using the ultraviolet ray/catalyst method. The purpose of this paper is to check the
design methodology for the PCB detoxification plant by the application of probabilistic safety analysis. First, possible hazardous
events were determined; second, the weakest points in these hazardous events were established; and third, the impact when
failures arise at the weak points in the system were studied. We clarified the preventive measures as follows. To prevent
PCBs leaking into the environment, select leak-tight valves for the piping containing PCBs, and reduce the number of valves.
To prevent fire or explosions due to leaks of an inflammable mixture, select leak-tight valves, reduce the number of valves
installed in the piping, and improve the reliability of the suppression tank in the isopropyl alcohol (IPA) recovery unit.
Received: February 27, 2001 / Accepted: June 17, 2002 相似文献