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831.
Geochemistry in the modern soil survey program 总被引:1,自引:0,他引:1
Wilson MA Burt R Indorante SJ Jenkins AB Chiaretti JV Ulmer MG Scheyer JM 《Environmental monitoring and assessment》2008,139(1-3):151-171
Elemental analysis has played an important role in the characterization of soils since inception of the soil survey in the
US. Recent efforts in analysis of trace and major elements (geochemistry) have provided necessary data to soil survey users
in a variety of areas. The first part of this paper provides a brief overview of elemental sources, forms, mobility, and bioavailability;
critical aspects important to users of soil survey geochemical data for appropriate use and interpretations. Examples are
provided based on data gathered as part of the US soil survey program. The second part addresses the organization of sample
collection in soil survey and how soil surveys are ideally suited as a sampling strategy for soil geochemical studies. Geochemistry
is functional in characterization of soil types, determining soil processes, ecological evaluation, or issues related to soil
quality and health, such as evaluating suitability of soils for urban or agricultural land use. Applications of geochemistry
are on-going across the US and are documented herein. This analytical direction of soil survey complements historic efforts
of the National Cooperative Soil Survey Program and addresses the increasing need of soil survey users for data that assists
in understanding the influence of human activities on soil properties. 相似文献
832.
Baba A Ereeş FS Hiçsönmez U Cam S Ozdilek HG 《Environmental monitoring and assessment》2008,139(1-3):277-285
Fifteen bottled mineral waters purchased at random all over Turkey were analyzed for their chemical composition by OPTIMA-2000
ICP-AES Perkin Elmer techniques. Results show a wide spread in the chemical specification of these mineral waters, with differences
in chemical composition observed in the regions being due to the geological environment and the majority of bottled mineral
waters exceeding the pH limit of Turkish drinking water standards. When the concentrations of elements are evaluated, it can
readily be seen that generally there are three types of mineral water in Turkey. The concentrations of Al, B, Ba, Cd, Cu,
Cr, Fe, Mn Pb and Zn in mineral water were compared with the limits established by the Turkish Standard for Natural Mineral
Waters (Turkish Official Gazette 2004); water standards prepared by World Health Organization (2006) and the United States of America Environmental Protection Agency (US EPA) drinking water standards (1993). Such a comparison shows that, except for Ba and Mn, the concentrations of the other heavy metals are lower than the limit
of the US.EPA in Turkey. Some parameters examined were found to comprise strong correlations pair-wise. 相似文献
833.
Statistical source identification of metals in groundwater exposed to industrial contamination 总被引:1,自引:0,他引:1
Tariq SR Shah MH Shaheen N Jaffar M Khalique A 《Environmental monitoring and assessment》2008,138(1-3):159-165
Levels of selected metals Na, Ca, Mg, K, Fe, Mn, Cr, Co, Ni, Cd, Pb and Mn were estimated by flame atomic absorption spectrophotometry
in groundwater samples from Kasur, a significant industrial city of Pakistan. Salient mean concentration levels were recorded
for: Na (211 mg/l), Ca (187 mg/l), Mg (122 mg/l), K (87.7 mg/l), Fe (2.57 mg/l) and Cr (2.12 mg/l). Overall, the decreasing
metal concentration order was: Na > Ca > Mg > K > Fe > Cr > Zn > Co > Pb > Mn > Ni > Cd. Significantly positive correlations
were found between Na–Cr (r = 0.553), Na–Mn (r = 0.543), Mg–Fe (r = 0.519), Mg–Cr (r = 0.535), Pb–K (r = 0.506) and Pb–Ni (r = 0.611). Principal Component Analysis and Cluster Analysis identified tannery effluents as the main source of metal contamination
of the groundwater. The present metal data showed that Cr, Pb and Fe levels were several times higher than those recommended
for water quality by WHO, US-EPA, EU and Japan. The elevated levels of Cr, recorded as 21–42 fold higher compared with the
recommended quality values, were believed to originate from the tanning industry of Kasur. 相似文献
834.
Barman SC Singh R Negi MP Bhargava SK 《Environmental monitoring and assessment》2008,137(1-3):495-504
The present study deals with the effect of fireworks on ambient air quality during Diwali Festival in Lucknow City. In this
study, PM10, SO2, NO
x
and 10 trace metals associated with PM10 were estimated at four representative locations, during day and night times for Pre Diwali (day before Diwali) and Diwali
day. On Diwali day 24 h average concentration of PM10, SO2, and NO
x
was found to be 753.3, 139.1, and 107.3 μg m−3, respectively, and these concentrations were found to be higher at 2.49 and 5.67 times for PM10, 1.95 and 6.59 times for SO2 and 1.79 and 2.69 for NO
x
, when compared with the respective concentration of Pre Diwali and normal day, respectively. On Diwali day, 24 h values for
PM10, SO2, and NO
x
were found to be higher than prescribed limit of National Ambient Air Quality Standard (NAAQS), and exceptionally high (7.53
times) for PM10. On Diwali night (12 h) mean level of PM10, SO2 and NO
x
was 1,206.2, 205.4 and 149.0 μg m−3, respectively, which was 4.02, 2.82 and 2.27 times higher than their respective daytime concentrations and showed strong
correlations (p < 0.01) with each other. The 24 h mean concentration of metals associated with PM10 was found to be in the order of Ca (3,169.44) > Fe (747.23) > Zn (542.62) > Cu (454.03), > Pb (307.54) > Mn (83.90) > Co
(78.69) > Cr (42.10) > Ni (41.47) > Cd (34.69) in ng m−3 and all these values were found to be higher than the Pre Diwali (except Fe) and normal day. The metal concentrations on
Diwali day were found to be significantly different than normal day (except Fe & Cu). The concentrations of Co, Ni, Cr and
Cd on Diwali night were found to be significantly higher than daytime concentrations for Pre Diwali (control). The inter correlation
of metals between Ca with Pb, Zn with Ni and Cr, Cu with Co, Co with Mn, Ni with Cd, Mn with Cd, Ni with Cd and Cr, and Cr
with Cd showed significant relation either at p < 0.05 or P < 0.01 levels, which indicated that their sources were the same. The metals Cu, Co, Ni, Cr and Cd showed significant (p < 0.01) association with PM10. These results indicate that fireworks during Diwali festival affected the ambient air quality adversely due to emission
and accumulation of PM10, SO2, NO
x
and trace metals.
ITRC Communication Number 2538 相似文献
835.
Ikem A Campbell M Nyirakabibi I Garth J 《Environmental monitoring and assessment》2008,140(1-3):69-81
Anthropogenic sources of pollution can significantly contribute to elevated concentrations of toxic elements in soils. A preliminary
survey of trace elements content and their availability in residential soils from New Madrid County, Missouri was undertaken.
Mean elemental concentrations (mg kg−1, dry wt) of sixty two soil samples were: As 6.6, Be 0.8, Cd 1.6, Co 9.7, Cr 24.5, Cu 18.1, Fe 9951, Mn 298, Ni 15.6, Pb 48.8,
V 42.1, Zn 95.5 and Hg 0.05. The US EPA preliminary remediation goals (PRGs) was only exceeded by As (7 % of samples) and
V (8% of samples). The Missouri average background values were exceeded by Pb (69%), Zn (31%), Cu (27%), As (23%), Be (19%),
Co (18%), Ni (16%), V (8%) and Mn (2%). Crustal enrichments (EFc) for As (97), Cr (6), Cu (10), Pb (121), V (7), and Hg (17) were highest for North Lilbourn soils. Fractionation experiment
revealed that Fe (54–79%) was in the residual phase while Zn (70–90%), Mn (88–92%), As (59–81%) and Pb (63–79%) were potentially
available in soils. Factor loadings of the element concentrations on principal components 1, 2 and 3 accounted for over 81%
variance of the data set. The factor loadings suggested that apart from natural contributions of trace elements to the soils,
human activities possibly accounted for other inputs in soils. 相似文献
836.
Marcelo Enrique Conti Domenico Cucina Mauro Mecozzi 《Environmental Modeling and Assessment》2008,13(4):553-565
A regression model is proposed for studying the relationship between trace metals concentrations and weights of individuals
of Monodonta turbinata (Born), a gastropod mollusc used as a trace metal biomonitor of marine coastal areas. The model herein presented was developed
including sites as reference factors and showed very good correlations. The prevision model of contamination gave good results
for this kind of pollutants, and it can be used as a tool for monitoring programmes. 相似文献
837.
Omar Ali Al-Khashman 《The Environmentalist》2008,28(3):203-215
The present study investigates the physical, chemical, and biological characteristics of spring water samples in Shoubak area
in the southern Jordan. The samples were collected from May 2004 to May 2005. All samples were analyzed for temperature, conductivity,
dissolved oxygen, pH, major cations (Ca2+, Mg2+, K+, Na+), major anions (Cl−, NO3−, HCO3−, SO42−, PO43−, F−), and trace metals (Fe2+, Al3+, Mn2+, Cu2+, Cr3+, Ni2+, Zn2+, Pb2+, Cd2+). Water quality for available springs showed high salinity through long period of contact with rocks. The ion concentrations
in the water samples were from dissolution of carbonate rocks and ion exchange processes in clay. The general chemistry of
water samples was typically of alkaline earth waters with prevailing bicarbonate chloride. Some springs showed elevated nitrate
and sulfate contents which could reflect to percolation from septic tanks, cesspools, and agricultural practices. The infiltration
of wastewater from cesspools and septic tanks into groundwater is considered the major source of water pollution. The results
showed that there were great variations among the analyzed samples with respect to their physical, chemical and biological
parameters, which lie below the maximum permissible levels of the Jordanian and WHO drinking water standards. The results
indicate that the trace metals of spring’s water of Shoubak area do not generally pose any health or environmental problems.
Factor analysis was used to identify the contributers to water quality. The first factor represents major contribution from
anthropogenic activities, while the second one represents major contribution from natural processes. 相似文献
838.
电感耦合等离子体质谱法测定饮用水中15种稀土元素 总被引:2,自引:0,他引:2
采用电感耦合等离子体质谱法测定饮用水中15种稀土元素,采取内标校正法,以Rh、Re、Bi为内标,结合优化仪器条件和干扰校正方程来消除干扰.15种稀土元素的方法检出限为0.000 2μg/L~ 0.003 μg/L,混合标准溶液平行测定的RSD< 6%,饮用水样品的加标回收率为98%~120%. 相似文献
839.
840.