全文获取类型
收费全文 | 205篇 |
免费 | 3篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 6篇 |
废物处理 | 20篇 |
环保管理 | 20篇 |
综合类 | 32篇 |
基础理论 | 33篇 |
污染及防治 | 85篇 |
评价与监测 | 15篇 |
社会与环境 | 6篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 5篇 |
2013年 | 20篇 |
2012年 | 4篇 |
2011年 | 20篇 |
2010年 | 19篇 |
2009年 | 21篇 |
2008年 | 14篇 |
2007年 | 15篇 |
2006年 | 10篇 |
2005年 | 9篇 |
2004年 | 12篇 |
2003年 | 4篇 |
2002年 | 8篇 |
2001年 | 7篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1991年 | 1篇 |
1981年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有217条查询结果,搜索用时 31 毫秒
141.
142.
Taeil Jang George Vellidis Jeffrey B. Hyman Erin Brooks Lyubov A. Kurkalova Jan Boll Jaepil Cho 《Environmental management》2013,51(1):209-224
Understanding the best way to allocate limited resources is a constant challenge for water quality improvement efforts. The synoptic approach is a tool for geographic prioritization of these efforts. It uses a benefit-cost framework to calculate indices for functional criteria in subunits (watersheds, counties) of a region and then rank the subunits. The synoptic approach was specifically designed to incorporate best professional judgment in cases where information and resources are limited. To date, the synoptic approach has been applied primarily to local or regional wetland restoration prioritization projects. The goal of this work was to develop a synoptic model for prioritizing watersheds within which suites of agricultural best management practices (BMPs) can be implemented to reduce sediment load at the watershed outlets. The model ranks candidate watersheds within an ecoregion or river basin so that BMP implementation within the highest ranked watersheds will result in the most sediment load reduction per conservation dollar invested. The model can be applied anywhere and at many scales provided that the selected suite of BMPs is appropriate for the evaluation area’s biophysical and climatic conditions. The model was specifically developed as a tool for prioritizing BMP implementation efforts in ecoregions containing watersheds associated with the USDA-NRCS conservation effects assessment project (CEAP). This paper presents the testing of the model in the little river experimental watershed (LREW) which is located near Tifton, Georgia, USA and is the CEAP watershed representing the southeastern coastal plain. The application of the model to the LREW demonstrated that the model represents the physical drivers of erosion and sediment loading well. The application also showed that the model is quite responsive to social and economic drivers and is, therefore, best applied at a scale large enough to ensure differences in social and economic drivers across the candidate watersheds. The prioritization model will be used for planning purposes. Its results are visualized as maps which enable resource managers to identify watersheds within which BMP implementation would result in the most water quality improvement per conservation dollar invested. 相似文献
143.
Han Sang Cho Hee Sun Moon Jae Yong Lim Jae Young Kim 《Journal of Material Cycles and Waste Management》2013,15(1):82-89
This study investigated the effect of long chain fatty acids (LCFAs) removal as a pretreatment prior to anaerobic digestion on the production of methane from food waste. The results showed that the anaerobic digestion of food waste containing 1.6 g COD/L of LCFAs was not inhibited (4 days lag-time, 78.3 % methane recovery in 35 days) compared to that of lipid free food waste (3 days lag time, 72.5 % methane recovery in 35 days); however, some unsaturated LCFAs, which are toxic to microorganism, were accumulated in the batch anaerobic digestion reactor. Meanwhile, in a methanogenic activity study, the activity of methanogens was observed to be linearly inhibited by the presence of more than 1 g COD/L of LCFAs. The possibility of the accumulation of unsaturated LCFAs in the reactor should be considered when operating a large-scale continuous system. 相似文献
144.
145.
S. H. Park E. J. Kim T. H. Yun J. H. Lee C. K. Kim Y. H. Seo S. A. Oh S. S. Choi S. J. Cho M. S. Kim G. Y. Han M. Y. Kim H. S. Jeong D. S. Cheon H. S. Kim 《Food and environmental virology》2010,2(2):69-73
Waterborne outbreaks of enteric viruses are a major public health concern. The present study has been carried out to assess the presence of enteric viruses responsible for human acute gastroenteritis (AGE) in groundwater intended for drinking and produce washing. In total, 62 samples from groundwater for drinking and produce washing collected from Dec 2007 to Dec 2008 in Seoul were tested for enteric viruses using conventional RT–PCR, ELISA, and real-time RT–PCR. Our results showed that enteric viruses were detected in 7 (8.8%) groundwater samples. Rotaviruses were detected in 3 (4.8%) of the samples by ELISA; human adenoviruses were detected in 2 (3.2%) of the samples by ELISA; and nested RT–PCR detected noroviruses in 2 (3.2%) of the samples. In one of the groundwater sample, the norovirus RNA was detected by conventional RT–PCR which was confirmed positive by real-time RT–PCR. Additionally, real-time RT–PCR successfully detected norovirus RNA in five out of 62 water samples (8.1%). The data demonstrate that real-time RT–PCR will be useful as a rapid and sensitive method for detecting norovirus in water samples. Phylogenetic analysis revealed that the noroviruses detected in two of the groundwater samples belonged to GII-4. These studies can provide important information for the prevalence of enteric viruses in Korean groundwater. 相似文献
146.
In this study, the effect of moisture supply during desiccation in a landfill liner system under the climatic conditions prevalent
in spring and summer in Korea was investigated. The specimens used in the test were a mixture of dredged clay (parent soil)
combined with additives Pa or Pb (proprietary cementing materials — Pa is mostly silicate powder and Pb is mostly quicklime).
The mixing ratio of the dredged clay to Pa was 5: 1 and that for dredged clay to Pb was 20: 3 (w/w). The effect of moisture
supply to the liner system was evaluated in three ways: the uniaxial compressive strength, permeability, and shrinkage tests
during desiccation. From the results, the compressive strength of the Pa/Pb-clay mixture without moisture supply decreased
more dramatically than that of the Pa/Pb-clay mixture with moisture supply during desiccation. The permeability of the latter
decreased more rapidly than that of the former. Shrinkage of the Pa/Pb-clay mixture with moisture supply during the curing
process was less than that of the Pa/Pb-clay mixture without moisture supply. 相似文献
147.
C. Wretfors S.-W. Cho M. S. Hedenqvist S. Marttila S. Nimmermark E. Johansson 《Journal of Polymers and the Environment》2009,17(4):259-266
The next generation of manufactured products must be sustainable and industrially eco-efficient, making materials derived
from plants an alternative of particular interest. Wheat gluten (WG) is an interesting plant material to be used for production
of plastic similar materials due to its film-forming properties. For usage of plastics in a wider range of applications, composite
materials with improved mechanical properties are demanded. The present study investigates the possibilities of reinforcing
WG plastics with hemp fibers. Samples were manufactured using compression molding (130 °C, 1600 bar, 5 min). Variation in
fiber length, content (5, 10, 15 and 20 wt%) and quality (poor, standard, good) were evaluated. Mechanical properties and
structure of materials were examined using tensile testing, light and scanning electron microscopy. Hemp fiber reinforcement
of gluten plastics significantly influenced the mechanical properties of the material. Short hemp fibers processed in a high
speed grinder were more homogenously spread in the material than long unprocessed fibers. Fiber content in the material showed
a significant positive correlation with tensile strength and Young’s modulus, and a negative correlation with fracture strain
and strain at maximum stress. Quality of the hemp fibers did not play any significant role for tensile strength and strain,
but the Young’s modulus was significantly and positively correlated with hemp fiber quality. Despite the use of short hemp
fibers, the reinforced gluten material still showed uneven mechanical properties within the material, a result from clustering
of the fibers and too poor bonding between fibers and gluten material. Both these problems have to be resolved before reinforcement
of gluten plastics by industrial hemp fibers is applicable on an industrial scale. 相似文献
148.
Ravindranadh Koutavarapu Mohan Rao Tamtam Chimpiri Rao Myl Migyung Cho Jaesool Shim 《环境科学学报(英文版)》2021,33(4):326-340
Global environmental problems have been increasing with the growth of the world economy and have become a crucial issue. To replace fossil fuels, sustainable and eco-friendly catalysts are required for the removal of organic pollutants. In this study, nickel ferrite (NiFe2O4) was prepared using a simple wet-chemical synthesis, followed by calcination; bismuth phosphate (BiPO4) was also prepared using a hydrothermal method. Further, NiFe2O4/BiPO4 nanocomposites were prepared using a hydrothermal technique. Numerous characterization studies, such as structural, morphology, surface area, optical, photoluminescence, and photoelectrochemical investigations, were used to analyze NiFe2O4/BiPO4 nanocomposites. The morphology analysis indicated a successful decoration of BiPO4 nanorods on the surface of NiFe2O4 nanoplate. Further, the bandgap of the NiFe2O4/BiPO4 nanocomposites was modified owing to the formation of a heterostructure. The as-prepared NiFe2O4/BiPO4 nanocomposite exhibited promising properties to be used as a novel heterostructure for tetracycline (TC) and Rhodamine B (RhB) removal. The NiFe2O4/BiPO4 nanocomposite degrades TC (98%) and RhB (99%) pollutants upon solar-light irradiation within 100 and 60 min, respectively. Moreover, the trapping experiments confirmed the Z-scheme approach of the prepared nanocomposites. The efficient separation and transfer of photogenerated electron-hole pairs rendered by the heterostructure were confirmed by utilizing electrochemical impedance spectroscopy, photocurrent experiments, and photoluminescence. Mott–Schottky measurements were used determine the positions of the conduction and valence bands of the samples, and the detailed mechanism of photocatalytic degradation of toxic pollutants was projected and discussed. 相似文献
149.
Risk Analysis of Volatile Organic Compounds Through Daily Life Cycle in the Industrial City in Korea
This study analyzed the risk of exposure to volatile organic compounds (VOCs) through a study of activity patterns in the Korean industrial city, Ulsan. The daily life cycle patterns(LCPs) of 331 people in Ulsan were surveyed and the average LCPs in Ulsan were obtained by statistical analysis. Nine to twelve personal air samples of VOC exposure at the breathing zones were collected at each LCP. This included hours for sleeping,cooking and eating, going to and from work, working, participating in field or outdoor activities, reading, watchingTV, and shopping. The components and concentrations of the collected VOCs were identified by a Gas Chromatography-MassDetector (GC-MS). The overall reproducibility of all GC analytical procedures of the simultaneously collected duplicatesample pairs represented a mean of percent differences rangingfrom about 9 to 13%. For the general population of Ulsan, thecarcinogenic and non-carcinogenic risk of exposure to theVOCs during the LCPs was evaluated. The carcinogenic riskwas analyzed using both the chronic daily exposure orlifetime average daily exposure (CDI) and the cancerpotency factor. The non-carcinogenic risk was analyzedusing both the CDI and the chronic reference dose.The major chemical forms of the identified VOCs were oxidized forms (43%), aliphatic alkanes (29%) and aromatics (15%). Even though the highest total exposure strength per unit time of each activity was observed during shopping, the highest totalamount of exposure to VOCs was identified as the exposure duringwork. The total carcinogenic risk of exposure to the carcinogenicVOCs through daily life cycle in Ulsan was 2.0 × 10-4which is substantially exceeding the permissible carcinogenicrisk level, 10-5 10-6. The carcinogenic riskduring most of the life cycle activities, except forreading, mainly performed indoors, was higher than that ofthe activities performed outdoors. The carcinogenic risk bybenzene exposure was about 56% (time weighted average) ofthe total carcinogenic risk by the exposure to thecarcinogenic VOCs. During cooking and eating, shopping andout door activities, however, the carcinogenic risk by theexposure to chlorinated compounds like chloroform exceededthe exposure to benzene. The overall hazard index (non-carcinogenic risk) by a chronic exposure to carcinogenicand non-carcinogenic VOCs through daily life cycle in Ulsanwas evaluated as 3.91 × 10-1, which is much less than1.0 considered as a hazard level to human health, and thusit seems likely not to produce a severe health hazard. 相似文献
150.
Oxidation of organophosphorus pesticides for the sensitive detection by a cholinesterase-based biosensor 总被引:3,自引:0,他引:3
A potentiometric flow injection-type biosensor developed in our laboratory was used for the determination of organophosphorus pesticides (OPs). The principle of the biosensor is that the degree of inhibition of a sensor enzyme by an OP is dependent on the concentration of the pesticide. The sensor system consisted of a reactor with acetylcholinesterase (AChE) immobilized on a controlled pore glass and a detector with a tubular H(+)-selective membrane electrode. In order to examine the possibility of enhancing the sensitivity of the sensor by converting OPs to oxidized forms (stronger inhibitors), a comparison of the degree of enzyme inhibition by OPs at 10(-6) M before and after their oxidation was made. All of the ten pesticides tested exhibited greater inhibitory power toward the sensor enzyme following oxidation. All of the oxidized pesticides at 10(-6) M inhibited the sensor enzyme to a considerable degree, demonstrating the utility of the developed method for the class-specific determination of OPs. A calibration curve for diazinon, over the concentration range of 10(-11)-10(-4) M, was obtained. The lower detection limit was 2 x 10(-10) M. Treatment of the inhibited enzyme with pyridine-2-aldoxime restored the enzyme to near full activity, allowing repeated use of the sensor. 相似文献