全文获取类型
收费全文 | 466篇 |
免费 | 3篇 |
国内免费 | 8篇 |
专业分类
安全科学 | 13篇 |
废物处理 | 47篇 |
环保管理 | 50篇 |
综合类 | 39篇 |
基础理论 | 56篇 |
环境理论 | 1篇 |
污染及防治 | 189篇 |
评价与监测 | 56篇 |
社会与环境 | 19篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 12篇 |
2022年 | 48篇 |
2021年 | 36篇 |
2020年 | 18篇 |
2019年 | 17篇 |
2018年 | 22篇 |
2017年 | 21篇 |
2016年 | 24篇 |
2015年 | 15篇 |
2014年 | 24篇 |
2013年 | 68篇 |
2012年 | 20篇 |
2011年 | 18篇 |
2010年 | 10篇 |
2009年 | 13篇 |
2008年 | 8篇 |
2007年 | 11篇 |
2006年 | 9篇 |
2005年 | 12篇 |
2004年 | 7篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1972年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1964年 | 2篇 |
排序方式: 共有477条查询结果,搜索用时 0 毫秒
1.
Rashid Muhammad Khan Muhammad Naseem Jalbani Nusrat 《Food and environmental virology》2021,13(1):44-52
Food and Environmental Virology - Drinking water supplies in the developing world often serve as a biosphere for various organisms. Viral gastroenteritis is a neglected area of research in... 相似文献
2.
This paper investigates and compares the performances of polylactic acid (PLA)/kenaf (PLA-K) and PLA/rice husk (PLA-RH) composites
in terms of biodegradability, mechanical and thermal properties. Composites with natural fiber weight content of 20% with
fiber sizes of less than 100 μm were produced for testing and characterization. A twin-screw extrusion was used to compound
PLA and natural fibers, and extruded composites were injection molded to test samples. Flexural and Izod impact test, TGA,
soil burial test and SEM were used to investigate properties. All results were compared to a pure PLA matrix sample. The flexural
modulus of the PLA increased with the addition of natural fibers, while the flexural strength decreased. The highest impact
strength (34 J m−1), flexural modulus (4.5 GPa) and flexural strength (90 MPa) were obtained for the composite made of PLA/kenaf (PLA-K), which
means kenaf natural fibers are potential to be used as an alternative filler to enhance mechanical properties. On the other
hand PLA-RH composite exhibits lower mechanical properties. The impact strength of PLA has decreased when filled with natural
fibers; this decrease is more pronounced in the PLA-RH composite. In terms of thermal stability it has been found that the
addition of natural fibers decreased the thermal stability of virgin PLA and the decrement was more prominent in the PLA-RH
composite. Biodegradability of the composites slightly increased and reached 1.2 and 0.8% for PLA-K and PLA-RH respectively
for a period of 90 days. SEM micrographs showed poor interfacial between the polymer matrix and natural fibers. 相似文献
3.
Abdellatif Ouahsine Hassan Smaoui Khouane Meftah Philippe Sergent François Sabatier 《Environmental Fluid Mechanics》2013,13(2):169-187
We present a numerical model based on the hydro-morphodynamical coupling to study coastal sandbar migration. In order to improve both nonlinear and dispersive wave processes in relatively shallow water, we developed a finite element model based on the Legendre polynomials and on the Extended Boussinesq model. This model reproduces the propagation of wave trains with a high degree of accuracy on a greater range of depths than the standard Boussinesq models. We also implemented the Total Variation Diminishing schemes to improve the quality of the computed hydrodynamic fields, especially in areas where sharp flow gradients occurred. The coupled morpho-hydrodynamical model is then used to simulate the migration of real sandbars observed at Rousty beach (Mediterranean French coast). For verification the model results are compared with field measurements obtained from a small-scale field campaign carried out over two years at Rousty beach, and the results of this comparison are thoroughly discussed and analyzed. 相似文献
4.
Ashraf A. Hassan Saleh M. Abdullah Ibrahim A. Khardali Ghassan A. Shaikhain Magbool E. Oraiby 《毒物与环境化学》2013,95(9):1477-1483
The habit of khat chewing is widespread with a deep-rooted sociocultural tradition in these regions and as such poses a public health problem. The use of pesticides is considered to be indispensable practice for the production of adequate food supply for the increasing demands by the global population and for control of insect-borne diseases. Thus, contamination of the environment with pesticides and entry of these chemicals into the food chain is unavoidable especially in developing countries. The main objective of our current study was to assess pesticide pollution of khat leaves (unknown origin) obtained while being smuggled into the Kingdom of Saudi Arabia and to be used in Jazan area. A total of 120 khat leaf samples were extracted using solid-phase extraction followed by gas chromatography/mass spectrometry analysis for the presence of 69 standard pesticides using an internal standard, tiphenyl phosphate. No pesticide residues were detected in all the studied samples. These data as preliminary and more experiments need to be performed to confirm our present findings. Routine monitoring of the pesticide residues is important for the prevention, control, and reduction of environmental pollution and also for legal decisions to minimize health risks. 相似文献
5.
A sensitive, accurate and reproducible method for the analysis of metoclopramide, a gastrointestinal drug, has been described. An isocratic HPLC elution method was employed which requires about 10 minutes to be performed. The concentration of metoclopramide hydrochloride preparations was found to be 95.1 ±0.3% and 94.21 ±0.25% in tablet and injection formulations, respectively. 相似文献
6.
Fuels like coal and rubber are frequently used for brick burning. However, both coal and rubber contain heavy metals. These heavy metals may elutriate in the wake of fly ash or may adsorb or absorb in the product. The present work deals with the analysis of heavy metals in some samples collected from brick burning industries located in the vicinity of a metropolitan city, Peshawar, Pakistan. Samples from raw clay, product, chimney scale and fossil fuel & rubber were collected and leached with acid mixture. The leachates were concentrated and analyzed by atomic absorption spectrophotometer for the determination of chromium (Cr), lead (Pb), cadmium (Cd) and antimony (Sb). It was observed that heavy metals are present in clay, brick and chimney scale. However, significant amount of these metals was observed in chimney scale. It is inferred that such emanations laden with heavy metals are accompanying the stack gases which are being dumped in to the environment. In order to avoid environmental problems, strict environmental regulations shall be enforced and a constant check on these emanations to the environment must be made to ensure clean air act. 相似文献
7.
M.?Masudul?Hassan M.?Rabiul?Islam Laurence?T.?Drzal Mubarak?A.?KhanEmail author 《Journal of Polymers and the Environment》2005,13(3):293-300
To improve the mechanical performance of natural lignocellulosic jute yarn, grafting with [3-(trimethoxysilyl) propylmethacrylate] (TMSPM) monomer has been performed on in situ UV radiation and optimized the monomer concentration (30%) and irradiation time (30 min). Effect of various amino acids (1%) as additives in TMSPM with photografted jute yarn at optimized system has been studied. The polymer loading (PL) and tensile properties like tensile strength (TS) and elongation at break (Eb) of treated samples were enhanced by incorporation of amino acids and the highest properties (TS = 300% and Eb = 386%) achieved by the sample treated with l-Arginine (Arg) with 32.5% PL value. Weak acid like 3% acetic acid and inorganic acid like 1% sulfuric acid were also incorporated in the optimized system of TMSPM grafting and compared their effect on the tensile properties with amino acid treated samples. Water absorption and weathering resistance of treated and untreated samples were also performed and treated sample showed lesser water uptake as well as less weight loss and mechanical properties as compared to untreated samples. 相似文献
8.
Rushdya R. A. Hassan Maisa M. A. Mansour 《Journal of Polymers and the Environment》2018,26(7):2698-2707
The current study is interested in evaluating the decay of cotton, Whatman and chemical pulp caused by Trichoderma harzianum and Paecilomyces variotii. The structural changes of the paper were evaluated by Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). The SEM results show differences in hyphae colonization and paper decay patterns between studied species under the current study; P. variotii caused an eroded structure in the cotton (cavity forming), whereas the initial T. harzianum colonization produced rupture and erosion (soft-rot decay type II) for the three types of paper ,the gaps were elongated with sharp pointed ends, which consisted either of individual cavities or in chains. Moreover, FTIR results confirmed that there a relationship could be observed between fungal decay and crystalline cellulose content because the intensity of peaks at 1335 and 1111 cm?1 significantly decreased due to the fungal decay. Furthermore, the intensity of O–H stretching absorption slightly decreased, and this may be attributed to hydrolysis of cellulose molecules. 相似文献
9.
Ben Jabeur Rim Fguiri Ali Jeday Mohamed-Razak Chekir Hassan Fatnassi Hicham Marvillet Christophe 《Journal of Material Cycles and Waste Management》2018,20(3):1857-1866
Journal of Material Cycles and Waste Management - This work presents an energy analysis of an industrial plant of production of Di-ammonium Phosphate (DAP plant). It aims to evaluate the important... 相似文献
10.
Amini Hassan Haghighat Gholam Ali Yunesian Masud Nabizadeh Ramin Mahvi Amir Hossein Dehghani Mohammad Hadi Davani Rahim Aminian Abd-Rasool Shamsipour Mansour Hassanzadeh Naser Faramarzi Hossein Mesdaghinia Alireza 《Environmental geochemistry and health》2016,38(1):25-37
Environmental Geochemistry and Health - There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in... 相似文献