全文获取类型
收费全文 | 728篇 |
免费 | 9篇 |
国内免费 | 23篇 |
专业分类
安全科学 | 34篇 |
废物处理 | 76篇 |
环保管理 | 68篇 |
综合类 | 51篇 |
基础理论 | 129篇 |
环境理论 | 1篇 |
污染及防治 | 242篇 |
评价与监测 | 117篇 |
社会与环境 | 37篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 11篇 |
2022年 | 89篇 |
2021年 | 71篇 |
2020年 | 16篇 |
2019年 | 30篇 |
2018年 | 36篇 |
2017年 | 44篇 |
2016年 | 48篇 |
2015年 | 33篇 |
2014年 | 40篇 |
2013年 | 96篇 |
2012年 | 39篇 |
2011年 | 49篇 |
2010年 | 22篇 |
2009年 | 33篇 |
2008年 | 17篇 |
2007年 | 17篇 |
2006年 | 10篇 |
2005年 | 8篇 |
2004年 | 9篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 2篇 |
1999年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1973年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有760条查询结果,搜索用时 236 毫秒
361.
Behzad Jabbaripour Mohammad Hossein Sadeghi Mohammad Reza Shabgard Hossein Faraji 《Journal of Manufacturing Processes》2013,15(1):56-68
Titanium aluminide intermetallics offer an attractive combination of low density and good oxidation, corrosion and ignition resistance with unique mechanical properties. In this study two series of machining tests are designed. Firstly the powder mixed electrical discharge machining (PMEDM) of γ-TiAl by means of different powders such as aluminum, chrome, silicon carbide, graphite and iron is performed to investigate the output characteristics of surface roughness and topography, material removal rate (MRR), electrochemical corrosion resistance of machined samples and also the machined surfaces are investigated by means of EDS and XRD analyses. Secondly after selection the aluminum powder as the most appropriate kind of powder, the current, pulse on time, powder size and powder concentration are changed in different levels for overall comparison between EDM and PMEDM output characteristics. In the first setting of input machining parameters, aluminum powder improves the surface roughness of TiAl sample about 32% comparing with EDM case and also aluminum particles with the size of 2 μm, in the second setting of input parameters lead to 54% enhancement of MRR comparing with EDM case. The electrochemical corrosion results show that, corrosion resistance of the samples which are machined by graphite and chrome powders respectively are about three and two times more than the sample which is machined without powder. 相似文献
362.
Al Attar L Al-Oudat M Kanakri S Budeir Y Khalily H Al Hamwi A 《Journal of environmental management》2011,92(9):2151-2158
This study was carried out to assess the radiological impact of Syrian phosphogypsum (PG) piles in the compartments of the surrounding ecosystem. Estimating the distribution of naturally occurring radionuclides (i.e. (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb) in the raw materials, product and by-product of the Syrian phosphate fertilizer industry was essential. The data revealed that the concentrations of the radionuclides were enhanced in the treated phosphate ore. In PG, (226)Ra content had a mean activity of 318 Bq kg(-1). The uranium content in PG was low, ca. 33 Bq kg(-1), because uranium remained in the phosphoric acid produced. Over 80% of (232)Th, (210)Po and (210)Pb present partitioned in PG. The presence of PG piles did not increase significantly the concentration of (222)Rn or gamma rays exposure dose in the area studied. The annual effective dose was only 0.082 mSv y(-1). The geometric mean of total suspended air particulates (TSP) ca. 85 μg m(-3). The activity concentration of the radionuclides in filtrates and runoff waters were below the detection limits (ca. 0.15 mBq L(-1) for (238)U, 0.1 mBq L(-1) for (232)Th and 0.18 mBq L(-1) for both of (210)Po and (210)Pb); the concentration of the radionuclides in ground water samples and Qattina Lake were less than the permissible limits set for drinking water by the World Health Organisation, WHO, (10, 1 and 0.1 Bq L(-1) for (238)U, (232)Th and both of (210)Po and (210)Pb, respectively). Eastern sites soil samples of PG piles recorded the highest activity concentrations, i.e. 26, 33, 28, 61 and 40 Bq kg(-1) for (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb, respectively, due to the prevailing western and north-western wind in the area, but remained within the natural levels reported in Syrian soil (13-32 Bq kg(-1) for (226)Ra, 24.9-62.2 Bq kg(-1) for (238)U and 10-32 Bq kg(-1) for (232)Th). The impact of PG piles on plants varied upon the plant species. Higher concentrations of the radionuclides were recorded for grass in comparison to broad-leaved plants. Among the species that grow naturally on PG piles, Inula, Ecballium and Polygonium may be radionuclides accumulators. A determined effort is needed at a national level to achieve a common and coherent approach to regulate PG piles or to consider it a resource material rather than waste or residue. 相似文献
363.
Mohammad Aslam Khan S. Akhtar Ali Shah 《Journal of Agricultural and Environmental Ethics》2011,24(6):629-644
South Asia is one of the most densely populated regions of the world, where despite a slow growth, agriculture remains the
backbone of rural economy as it employs one half to over 90 percent of the labor force. Both extensive and intensive policy
measures for agriculture development to feed the massive population of the region have resulted in land degradation and desertification,
water scarcity, pollution from agrochemicals, and loss of agricultural biodiversity. The social and ethical aspects portray
even a grimmer picture of the region with growing poverty mainly, amongst small farmers, food scarcity, and overall poor quality
of life. This article reviews the historical perspective of agriculture development in the region and gives a panoramic view
of the policy initiatives and their environmental as well as social and ethical spin-offs. The aim is to explore the environmental
and ethical dimensions of the agricultural development in South Asia and recommend a holistic approach in formulating plans
and programs to combat environmental degradation, hunger, and poverty resulting from unsustainable agricultural practices. 相似文献
364.
Heavy metal pollution caused by traffic activities is increasingly becoming a great threat to urban environmental quality
and human health. In this paper, soils of Kerman urban and suburban areas were collected to assess the potential effects of
traffic and other vehicle-related pollution by heavy metal accumulation in soils. Eighty-six samples were collected along
streets and from residential and rural sectors, as well as vehicle-related workshops from depth of 0–5 and 15–20 cm and analyzed
by flame atomic absorption spectrometry (FAAS) for heavy metals (Cd, Cr, Cu, Pb, Sn and Zn), as well as major elements (Al,
Ca, Fe and Mn). Several hot-spot areas were identified in the composite geochemical maps produced based on Geographical Information
System (GIS) technology. The majority of the hot-spot areas were identified to be vehicle-related workshops, fuel stations
and road junctions. The most polluted hot-spot in the study area was located in soils close to a car battery processing workshop
in the southwestern part of Kerman city, with concentrations of Cd (0.32 mg/kg), Cr (169 mg/kg), Cu (250 mg/kg), Pb (5,780 mg/kg),
Sn (27.2 mg/kg) and Zn (178 mg/kg) of 1, 8.5, 8.3, 230, 13.5 and 3 times more than the relevant mean concentrations in natural
soils, respectively. Traffic pollution has resulted in significant accumulation of heavy metals in soils and sediments, and
that level of accumulation varied remarkably among elements. Based on X-ray diffraction analysis, most parts of soils and
sediments of the Kerman basement consist of calcite and clay minerals. Abundance of clay minerals and medium to alkaline pH
causes low mobility of heavy metals in soils of Kerman. 相似文献
365.
Hossein Tabari Safar Marofi Mohammad Ahmadi 《Environmental monitoring and assessment》2011,177(1-4):273-287
Sixteen water quality parameters have been monitored at four stations located along the Maroon River during 1989?C2008. The trend analysis was performed on seasonal and annual time-scales using the Mann?CKendall test, the Sen??s slope estimator and the linear regression. The relationships of the water quality parameters to river discharge were also investigated. The statistical methods showed both positive and negative trends in annual water quality data. However, significant trends were detected by the statistical methods only in calcium, magnesium, sodium absorption ratio, pH, and turbidity series. The results indicated that the concentrations of the water quality parameters increased in spring and winter seasons, while the concentrations were diluted in summer and autumn seasons in the last two decades. Moreover, the highest numbers of significant trends were found in the spring and summer series, respectively. According to the regression analysis, most of the water quality parameters were negatively correlated with river discharge. 相似文献
366.
Ahmed MK Parvin E Arif M Islam MM Akter MS Khan MS 《Environmental monitoring and assessment》2011,182(1-4):197-204
The present investigation was undertaken to study the induction of DNA damage by lead chloride (PbCl(2)) in freshwater climbing perch Anabas testudineus using alkaline single cell gel electrophoresis (comet assay). Based on the LC(50) values of lead chloride of A. testudineus three different concentrations viz., 0.1, 1.0 and 2.0 mg/L were selected to expose fish. The DNA damage was observed in the gill, kidney and liver tissue as the percentage of DNA in comet tails and comet heads in the tissue of the exposed fish. DNA damage at different concentrations showed sensitivity to particular tissue. The liver tissue exhibited significantly (p < 0.01) higher DNA damage, followed by kidney and gill. However, the DNA damage was found to be dose dependent; at 2 mg/L of PbCl(2) the tail and head DNA of liver tissue were 57.84% and 39.49%, in kidney tissue the values were 52.36% and 44.97% whereas in gill tissue the values were 48.86% and 48.96% respectively. The current study explored the utility of the comet assay for in vivo laboratory studies using A. testudineus species for screening the genotoxic potential of lead chloride. 相似文献
367.
Umme Salma Zohora Mohammad Shahedur Rahman Abdul Wahab Khan Masahiro Okanami Takashi Ano 《环境科学学报(英文版)》2013
To enhance the production of lipopeptide antibiotic iturin A, nutrient contents of the culture mediums were investigated in both submerged and biofilm fermentations. As a carbon source maltose and as nitrogen source, fish protein was used. In submerged fermentation maltose uptake was found lower (12%) compared to biofilm fermentation (15%) that was associated with higher cellular growth in biofilm. However, requirement of nitrogen (fish protein) concentration was found similar in both submerged and biofilm fermentations. Production of iturin A in submerged fermentation with 12% maltose and 5% fish protein was 4450 mg/L, and in biofilm fermentation it was 5050 mg/L when 15% maltose and 5% fish protein was used. 相似文献
368.
Eivazzadeh Mehran Hassanvand Mohammad Sadegh Faridi Sasan Gholampour Akbar 《Environmental science and pollution research international》2021,28(42):59403-59415
Environmental Science and Pollution Research - The monthly and spatial variations of atmospheric dustfall (DF) and their elemental components were determined. The DF sampling was performed using... 相似文献
369.
Khazdair Mohammad Reza Boskabady Mohammad Hossein 《Environmental science and pollution research international》2021,28(39):54191-54208
Environmental Science and Pollution Research - Chemical warfare (CW) agents are toxic synthetic chemicals that affect human’s health, and sulfur mustard (SM) is a well-known chemical weapon... 相似文献
370.
Aborode Abdullahi Tunde Tsagkaris Christos Oyeyemi Ajagbe Abayomi Akanji Onigbinde Oluwanisola Essar Mohammad Yasir Ahmad Shoaib Khawaja Uzzam Ahmed Cruz-Martins Natália Batiha Gaber El-Saber 《Environmental science and pollution research international》2021,28(35):47685-47688
Environmental Science and Pollution Research - Nearly two-thirds of migrants residing in camps in Europe are women and children. Many of these children, being born on the way without essential... 相似文献