全文获取类型
收费全文 | 1690篇 |
免费 | 16篇 |
国内免费 | 73篇 |
专业分类
安全科学 | 76篇 |
废物处理 | 186篇 |
环保管理 | 183篇 |
综合类 | 163篇 |
基础理论 | 277篇 |
环境理论 | 2篇 |
污染及防治 | 650篇 |
评价与监测 | 163篇 |
社会与环境 | 63篇 |
灾害及防治 | 16篇 |
出版年
2023年 | 20篇 |
2022年 | 37篇 |
2021年 | 36篇 |
2020年 | 15篇 |
2019年 | 29篇 |
2018年 | 44篇 |
2017年 | 58篇 |
2016年 | 81篇 |
2015年 | 42篇 |
2014年 | 72篇 |
2013年 | 140篇 |
2012年 | 105篇 |
2011年 | 119篇 |
2010年 | 96篇 |
2009年 | 109篇 |
2008年 | 122篇 |
2007年 | 108篇 |
2006年 | 100篇 |
2005年 | 87篇 |
2004年 | 83篇 |
2003年 | 59篇 |
2002年 | 62篇 |
2001年 | 47篇 |
2000年 | 21篇 |
1999年 | 12篇 |
1998年 | 9篇 |
1997年 | 7篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 7篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有1779条查询结果,搜索用时 62 毫秒
951.
A highly sensitive enzyme electrode was prepared based on gold nanoparticles for measurement of pesticides. Gold nanoparticles of 25-30 nm were synthesized on a glassy carbon electrode by double-pulse technique while the coverage was controlled by applied potential and time. The gold nanoparticles were modified to form a self-assembled monolayer, followed by covalent binding of tyrosinase. The TYR-AuNP-GC electrode was compared with bare GC, AuNP-GC, and modified AuNP-GC and TYR-Au (plate type) electrodes in terms of cyclic voltammetry. The voltammograms well represent the sensitivity of enzymatic oxidation of catechol, substrates for the enzyme activity. The prepared electrode integrated into a continuous flow system and was tested to detect pesticides, such as 2,4-D, atrazine, and ziram. Under the optimized conditions of the flow system, the electrode performed reasonably according to the inhibition mechanism in the concentration range of 0.001-0.5 ng mL(-1). The enhanced performance was attributed to the favored microenvironment for the enzyme activity provided by SAM on gold nanoparticles. 相似文献
952.
Assessment of Wastewater Reuse Effects on Nutrient Loads from Paddy Field Using Field-Scale Water Quality Model 总被引:1,自引:0,他引:1
Sang Min Kim Sang June Im Seung Woo Park Jeong Jae Lee Brian L. Benham Tae Il Jang 《Environmental Modeling and Assessment》2008,13(2):305-313
CREAMS-PADDY, a modified version of the field-scale CREAMS model, simulates the hydrologic, sediment, and nutrient cycles
in paddy fields. The CREAMS-PADDY model was applied to estimate the effects of using wastewater for irrigation on nutrient
loads from paddy fields in Republic of Korea. The model was calibrated and validated using data from two rice paddy fields.
The coefficient of determination between observed and simulated total nitrogen and total phosphorus were 0.92 and 0.57, respectively,
for the calibration period and 0.84 and 0.73 for the validation period. Simulations showed that when using wastewater for
irrigation, the total nitrogen loads increased by 210% and total phosphorus by 1,270% when compared with conventional water
irrigation. The total nitrogen and total phosphorus concentration in the ponded water increased by 254 and 534%, respectively,
when compared with conventional water irrigation. The effect of reducing N and P fertilizer application rates by 10, 30, and
50% on nutrient loads exiting a paddy field were also simulated using the validated CREAMS-PADDY model. These simulations
indicated that total phosphorus loads from the paddy were reduced only slightly by reducing the fertilizer, while total nitrogen
loads were reduced by as much as 8.8, 16.6, and 24.4% when N ferlitizer rates were reduced by 10, 30, and 50%, respectively.
An erratum to this article can be found at 相似文献
953.
Takuro Nishina Chu Ngoc Kien Nguyen Van Noi Ha Minh Ngoc Chul-Sa Kim Sota Tanaka Kōzō Iwasaki 《Environmental monitoring and assessment》2010,169(1-4):285-297
This study assessed pesticide residues in soils, sediments, and vegetables in the Xuan Khe and Hop Ly communes located along the Chau Giang River in the Red River Delta, northern Vietnam. Samples were collected from agricultural areas within and outside of embankments built to prevent flooding. In Xuan Khe, the soils outside of the embankment were more clayey with higher organic matter contents compared with the inside, due to selective deposition during river flooding. Many of the soils contained significant amounts of pesticides including dichlorodiphenyltrichloroethane (DDT), dicofol, isoprothiolane, and metalaxyl although their levels were below the maximum allowable concentration set by the Vietnamese government. The spectrum of DDT derivatives found suggested that the source of DDTs was not contaminated dicofol. Soils in Hop Ly resembled soils in Xuan Khe but were relatively sandy; one field showed appreciable contents of DDT derivatives. The ratios of (p,p ′-dichlorodiphenyldichloroethylene + p,p ′-dichlorodiphenyldichloroethane)/∑DDT in the surface and subsurface soils in Hop Ly were 0.34 and 0.57, suggesting that the DDTs originated from recent application. Pesticide residues in soils were not likely to translocate into vegetable crops, except for metalaxyl. High concentrations of cypermethrins in kohlrabi leaves could be ascribed to foliar deposition. 相似文献
954.
This paper presents monitoring results of daily brick kiln stack emission and the derived emission factors. Emission of individual air pollutant varied significantly during a firing batch (7 days) and between kilns. Average emission factors per 1,000 bricks were 6.35–12.3 kg of CO, 0.52–5.9 kg of SO2 and 0.64–1.4 kg of particulate matter (PM). PM emission size distribution in the stack plume was determined using a modified cascade impactor. Obtained emission factors and PM size distribution data were used in simulation study using the Industrial Source Complex Short-Term (ISCST3) dispersion model. The model performance was successfully evaluated for the local conditions using the simultaneous ambient monitoring data in 2006 and 2007. SO2 was the most critical pollutant, exceeding the hourly National Ambient Air Quality Standards over 63 km2 out of the 100-km2 modelled domain in the base case. Impacts of different emission scenarios on the ambient air quality (SO2, PM, CO, PM dry deposition flux) were assessed. 相似文献
955.
The emission of nitrogen compounds from power plants accounts for a significant proportion of the total emissions of nitrogen to the atmosphere. This study seeks to understand the nature of chemical reactions in the atmosphere involving nitrogen, which is important in undertaking quantitative assessments of the contribution of such reactions to local and regional air pollution. The slant column density (SCD) of power-plant-generated NO(2) was derived using imaging differential optical absorption spectroscopy (I-DOAS) with scattered sunlight as a light source. The vertical structure of NO(2) SCD from power plant stacks was simultaneously probed using a pushbroom sensor. Measured SCDs were converted to mixing ratios in calculating the rate of NO(2) increase at the center of the plume. This study presents quantitative measurements of the rate of NO(2) increase in a rising plume. An understanding of the rate of NO(2) increase is important because SO(2) and NO(x) compete for the same oxidizing radicals, and the amount of NO(x) is related to the rates of SO(2) oxidation and sulfate formation. This study is the first to directly obtain the rate of NO(2) increase in power plant plumes using the I-DOAS technique. NO(2) increase rates of 60 and 70 ppb s(-1) were observed at distances of about 45 m from the two stacks of the Pyeongtaek Power Plant, northwest South Korea. 相似文献
956.
Jin Lee Eun-Sook Kim Bang-Sik Roh Seog-Won Eom Kyung-Duk Zoh 《Environmental monitoring and assessment》2013,185(9):7675-7691
The concentrations of trihalomethanes (THMs), including chloroform, bromodichloromethane, dibromochloromethane, and bromoform, and haloacetic acids (HAAs; monochloroacetic acid, monobromoacetic acid, dibromoacetic acid, dichloroacetic acid, and trichloroacetic acid) were measured in tap waters passing through water distribution systems of six water treatment plants in Seoul, Korea, and their associated health risks from exposure to THMs through ingestion, dermal contact, and inhalation were estimated using a probabilistic approach. The concentration ranges for total THMs and HAA5 were 3.9–53.5 and <LOD–49.5 μg/L, respectively. Among DBPs, chloroform, bromodichloromethane, dichloroacetic acid, and trichloroacetic acid were the most frequently detected. Spatial and seasonal variations in concentrations of THMs and HAAs in the six water distribution systems were significant (P?<?0.001).The mean lifetime cancer risks through ingestion, dermal contact, and inhalation during showering ranged as 7.23–10.06?×?10?6, 2.19–3.63?×?10?6, and 5.22–7.35?×?10?5, respectively. The major exposure route to THMs was inhalation during showering. Sensitivity analysis showed that shower time and shower frequency had a great impact on the lifetime cancer risk by the exposure to THMs in tap water. 相似文献
957.
The column-integrated optical and radiative properties of aerosols in the downwind area of East Asia were investigated based on sun/sky radiometer measurements performed from February 2004 to June 2005 at Gwangju (35.23° N, 126.84° E) and Anmyeon (36.54° N, 126.33° E), Korea. The observed aerosol data were analyzed for differences among three seasons: spring (March-May), summer (June-August), and autumn/winter (September-February). The data were also categorized into five types depending on the air mass origin in arriving in the measurement sites: (a) from a northerly direction in spring (S(N)), (b) from a westerly direction in spring (S(W)), (c) cases with a low ?ngstr?m exponent (<0.8) in spring (dust), (d) from a northerly direction in autumn/winter (AW(N)), and (e) from a westerly direction during other seasons (AW(W)). The highest ?ngstr?m exponents (α) at Gwangju and Anmyeon were 1.43?±?0.30 and 1.49?±?0.20, respectively, observed in summer. The lowest column-mean single-scattering albedo (ω) at 440 nm observed at Gwangju and Anmyeon were 0.89?±?0.02 and 0.88?±?0.02, respectively, during a period marked by the advection of dust from the Asian continent. The highest ω values at Gwangju and Anmyeon were 0.95?±?0.02 and 0.96?±?0.02, respectively, observed in summer. Variations in the aerosol radiative-forcing efficiency (β) were related to the conditions of the air mass origin. The forcing efficiency in summer was -131.7 and -125.6 W?m(-2) at the surface in Gwangju and Anmyeon, respectively. These values are lower than those under the atmospheric conditions of spring and autumn/winter. The highest forcing efficiencies in autumn/winter were -214.3 and -255.9 W?m(-2) at the surface in Gwangju and Anmyeon, respectively, when the air mass was transported from westerly directions. 相似文献
958.
An enhanced dual coil 2,4-dinitrophenylhydrazine (DNPH) derivatization method (dual coil/DNPH) allowed the quantitative determination
of formaldehyde (HCHO) in ambient air. In this method, traceable HCHO was collected using a coil sampler connected in series
and lacking a long sampling tube. It was then analyzed using liquid chromatography followed by UV detection of the DNPH derivatives.
The method is based on the reaction of formaldehyde with DNPH to produce 2,4-dinitrophenylhydrazone. The detection limits
(3σ) were 0.10–0.40 ppbv with a precision ranging from 0.84 to 4.09% RSD. The results of dual coil/DNPH and conventional DNPH
cartridge methods were generally well correlated: HCHO (dual coil/DNPH) = 0.97 (±0.13) vs. HCHO (DNPH Cartridge) + 0.33 (±0.33),
r = 0.82. The dual coil/DNPH method was used to measure gaseous HCHO in the atmosphere of Metropolitan Seoul during the summer
2000 and 2001, and in Gwangju during the fall of 2001 and 2002. The daytime mean concentration of HCHO was 4.52 (±5.69) and
3.21 (±1.27) ppbv in Metropolitan Seoul for 10–12 August 2000 and 29–31 May 2001, respectively, and 1.73 (±0.98), 3.04 (±2.25),
2.70 (±1.70), and 2.01 (±2.28) ppbv in Gwangju City during 22–27 September 2001, 17–24 October 2001, 9–13 October 2002, and
28 October to 2 November 2002, respectively. The HCHO in Seoul from 10–12 August 2000 was mainly the result of photochemical
processes, while direct emissions from vehicles and long-range transport of air from China contributed during 29–31 May 2001.
During 22–27 September 2001, 17–24 October 2001, and 9–13 October 2002 in Gwangju, the HCHO came primarily from photochemical
processes, although some air affected by biomass burning admixed in the late afternoon. The increase in the HCHO concentration
on 20 October 2001 and from 28 October to 2 November 2002 was attributed mainly to direct emissions from biomass burning in
farmland near the measurement site. 相似文献
959.
960.
Mutagenic activity of river water from a river near textile industrial complex in Korea 总被引:1,自引:0,他引:1
Kwon JH Lee HK Kwon JW Kim K Park E Kang MH Kim YH 《Environmental monitoring and assessment》2008,142(1-3):289-296
The mutagenic activity of XAD-2 adsorbates and water extracts recovered from nine locations of the Kumho River was tested on S. typhimurium TA98 strain to identify the source of the mutagenicity. A sampling site, receiving effluents from the textile industrial complex located in Daegu City, showed extraordinarily high mutagenic activity, especially in the presence of S9 mixture, at all sampling time in both XAD-2 adsorbates and dichloromethane extracts. This indicated the existence of the frame-shift mutagens in the Kumho River, same type of mutagens detected in previous studies by other researchers in the Nakdong River into which the Kumho River discharges. The fractionation study showed that the mutagenic chemicals in the river water are mid-polar. Furthermore, mean tail length obtained by single cell gel electrophoresis assay (Comet assay) showed consistent dose-dependent DNA damage, indicating that the chemicals in the river water not only act as frame-shift mutagens but also break human lymphocytes DNA strain. Chemical identification of the mutagens should be required. 相似文献