全文获取类型
收费全文 | 843篇 |
免费 | 1篇 |
国内免费 | 31篇 |
专业分类
安全科学 | 18篇 |
废物处理 | 57篇 |
环保管理 | 66篇 |
综合类 | 95篇 |
基础理论 | 141篇 |
污染及防治 | 351篇 |
评价与监测 | 91篇 |
社会与环境 | 47篇 |
灾害及防治 | 9篇 |
出版年
2023年 | 56篇 |
2022年 | 115篇 |
2021年 | 109篇 |
2020年 | 23篇 |
2019年 | 35篇 |
2018年 | 41篇 |
2017年 | 34篇 |
2016年 | 49篇 |
2015年 | 20篇 |
2014年 | 37篇 |
2013年 | 79篇 |
2012年 | 27篇 |
2011年 | 32篇 |
2010年 | 23篇 |
2009年 | 12篇 |
2008年 | 26篇 |
2007年 | 24篇 |
2006年 | 18篇 |
2005年 | 17篇 |
2004年 | 16篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 6篇 |
2000年 | 9篇 |
1999年 | 2篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1964年 | 2篇 |
1961年 | 1篇 |
排序方式: 共有875条查询结果,搜索用时 15 毫秒
1.
Morsheda Akhter Sagar Kumar Dutta Palash Kumar Dhar Jamil Ahmed Mohammed Nazrul Islam Khan Md. Khairul Amin Jahidul Islam 《环境质量管理》2023,32(4):149-160
Catalytic activity of spinel ferrite in breaking down toxic dye materials are promising due to their uniqueness. In this study, aluminum-doped copper zinc ferrite, Cu0.4Zn0.6-xAlxFe2O4 (x = 0.0, 0.2, 0.4, 0.6), a catalyst for toxic dye degradation is synthesized through chemical co-precipitation route. The formation of the spinel ferrite catalyst is initially confirmed by Fourier transform infrared spectra, which shows the frequency of metal-oxygen bond vibration at 539 and 427 cm−1 attributed to the tetrahedral and octahedral sites respectively. Higher intensity sharp peak of X-ray diffraction for (311) plane is the evidence for the phase purity and the formation of spinel ferrite. The crystallite size is found to decrease with the increase of Al3+ ion. The surface structure of the obtained particles is investigated using a scanning electron microscope. Analyses of the material's magnetic characteristics using a vibrating sample magnetometer (VSM) revealed that it is, in fact, a soft magnet, as evidenced by the loop of its hysteresis, which is narrow. The catalytic degradation of methylene blue dye under the mechanism of the photo-Fenton process is studied with the obtained spinel ferrites and the result is found to be as high as 96.5%. The process follows pseudo-second order kinetics and the Langmuir isotherm. 相似文献
2.
Amirhossein Moosavi Adel Nikfarjam 《International Journal of Sustainable Engineering》2019,12(3):174-188
In this paper, the inventory-routing problem is studied for a closed-loop supply chain. This closed-loop supply chain considers suppliers, manufacturers, whole-sellers, and disposal centers. To formulate this problem, a mixed integer linear programming model is proposed. This mathematical model minimizes the total costs of the supply chain, including the fixed and variable costs of vehicles, and holding inventory costs of final products and scraps. The proposed model considers the road roughness degree, multi-path setting and the heterogeneous fleet of vehicles, which increases its flexibility and the quality of solutions. Then, two symmetry-breaking constraints are proposed to reduce the complexity of the mathematical model. In order to evaluate the integrity of the proposed model, 20 instances of different sizes are randomly generated and solved. Finally, a comprehensive sensitivity analysis is conducted with respect to five key features of the problem, such as the impact of the symmetry-breaking constraints on the CPU time, multi-path setting, fixed cost of vehicles, heterogeneous fleet of vehicles, and lost sales. The results indicate that the consideration of multi-path setting and the heterogeneous fleet of vehicles improves the quality of solutions significantly. 相似文献
3.
Advanced oxidation technologies are a friendly environmental approach for the remediation of industrial wastewaters. Here, one pot synthesis of mesoporous WO_3 and WO_3-graphene oxide(GO) nanocomposites has been performed through the sol–gel method. Then, platinum(Pt) nanoparticles were deposited onto the WO_3 and WO_3-GO nanocomposite through photochemical reduction to produce mesoporous Pt/WO_3 and Pt/WO_3-GO nanocomposites. X-ray diffraction(XRD) findings exhibit a formation of monoclinic and triclinic WO_3 phases. Transmission Electron Microscope(TEM) images of Pt/WO_3-GO nanocomposites exhibited that WO_3 nanoparticles are obviously agglomerated and the particle sizes of Pt and WO_3 are ~ 10 nm and 20–50 nm, respectively. The mesoporous Pt/WO_3 and Pt/WO_3-GO nanocomposites were assessed for photocatalytic degradation of Methylene Blue(MB) as a probe molecule under visible light illumination.The findings showed that mesoporous Pt/WO_3, WO_3-GO and Pt/WO_3-GO nanocomposites exhibited much higher photocatalytic efficiencies than the pure WO_3. The photodegradation rates by mesoporous Pt/WO_3-GO nanocomposites are 3, 2 and 1.15 times greater than those by mesoporous WO_3, WO_3-GO, and Pt/WO_3, respectively. The key factors of the enhanced photocatalytic performance of Pt/WO_3-GO nanocomposites could be explained by the highly freedom electron transfer through the synergetic effect between WO_3 and GO sheets, in addition to the Pt nanoparticles that act as active sites for O2 reduction, which suppresses the electron hole pair recombination in the Pt/WO_3-GO nanocomposites. 相似文献
4.
Devendra Kumar Agrawal Prasanna Kumar Samal Nehal Ahmed Farooquee Lok Man Singh Palni 《The Environmentalist》2003,23(1):39-47
The Indian Himalayan Region (IHR) is suffering from environmental degradation due to population pressure and infra-structural needs. This is coupled with a natural setting, which creates problems of accelerated soil erosion and mass wasting. In view of these environmental difficulties and the growing concern for effective restoration, there has become an urgent need for multi-disciplinary coordinated improvement schemes. The mitigation of risk arising from hazardous mass wasting processes, through a careful and systematic approach, has helped in the development of the concept of Mountain Risk Engineering (MRE). The MRE practices involve an integrated approach to solving the infra-structural engineering problems of hilly and mountainous areas through environmentally conscious cost-effective and site-specific designs. However, the role of people's participation is extremely crucial for the success of such programs. This paper analyzes the perception of the local people about the approaches adopted in MRE participatory developmental programs and throws light on the intricacies of peoples' participation. 相似文献
5.
A. Wieraszko Z. Ahmed J. Armani N. Maqsood S. Philips H. Raja 《The Environmentalist》2005,25(2-4):145-155
Summary The influence of pulsed magnetic fields (PMF) on the properties of nervous tissue was investigated. Hippocampal slices or
synaptosomes obtained from hippocampal tissue were used as model systems. The amplitude of potentials recorded in vitro from one of the hippocampal pathways (Schaffer collaterals that use glutamate as a neurotransmitter) was employed as a measure
of the influence of magnetic fields on synaptic efficiency. The synaptic glutamate turnover and radioactive calcium accumulation
were used as markers of the PMF influence on biochemistry of synaptic mechanisms. The exposure of hippocampal slices for 30
min to PMF amplified evoked potentials. While the frequency of 0.16 Hz exerted the strongest effect, lower (0.01, 0.07, 0.03
Hz) and higher (0.5 Hz) frequencies were much less effective. The enhancement of the neuronal excitability was correlated
with significant increase in the neuronal spontaneous activity mediated by electrical synapses. The PMF-induced changes in
the excitability of the tissue were accompanied by an increase in the synaptic turnover of glutamate. The release of radioactive
D-Aspartate (a glutamate analog used as a marker for glutamate turnover) from the slices, and its uptake by synaptosomes were
enhanced, and reduced respectively, following the stimulation with pulsed magnetic fields. The frequency which was the most
efficient in amplification of evoked potentials (0.16 Hz) was also the most effective in the modulation of the release and
uptake processes. The PMF-induced changes in neurotransmitter turnover coincided with an increase in 45Ca2+ accumulation observed in hippocampal slices exposed to PMF. 相似文献
6.
7.
Wafa Feki-Sahnoun Asma Hamza Mabrouka Mahfoudi Ahmed Rebai Malika Bel Hassen 《Environmental science and pollution research international》2014,21(19):11481-11499
Microphytoplankton data along the southern Tunisian coasts have been monitored weekly since 1995. This study used the data collected during the period 2000–2007 to determine the temporal variability patterns and to characterize the geographical structures of microphytoplankton populations. The methodological approach consisted in isolating the temporal variability common to all sampled sites and in analyzing the “residual” site-specific component. Multivariate ordination methods were used to determine the seasonal and interannual variability. The temporal pattern shared by all sites was highlighted and the seasonal cycle of the most frequent phytoplankton communities contrasted the diatoms winter-spring species to the dinoflagellates summer-fall species. Multitable comparison allowed the identification of three areas exhibiting similar phytoplankton population variability. The results, despite the coastal location of sampling sites, indicated that hydrodynamic and geomorphologic properties of the different areas as well as anthropogenic activities play a key role in the structure of the phytoplankton communities. 相似文献
8.
9.
Assessment of irrigation system sustainability using the Theil–Sen estimator of slope of time series
Shamseddin Musa Ahmed 《Sustainability Science》2014,9(3):293-302
Agriculture, especially the irrigated sector, is the mainstay of Sudan’s economy as it accounts for 40 % of gross domestic product (GDP) and employs 70 % of the workforce. The economic viability of irrigated schemes is dependent on three factors: crop yield, water management and cropped area. The research question of this study was whether or not the current status of these factors can be sustained in order to maintain the economic viability of irrigation systems? To answer this question, a new (to the best of the author’s knowledge) approach was developed based on time series analysis, and on the Theil–Sen estimator of slope. The study defined sustainability conceptually as “the ability of an irrigation system to sustain crop yields using the optimum cropped area and water consumption to realize the economic viability of the irrigation system without a decline in soil quality and environment”. Time series datasets of crop yields, cropped area and irrigation water consumption are collected routinely by statistical departments. Any abrupt years in the development of trends were detected and related to their driving forces/causes, of which climatic conditions and marketing policies were found to be the most important. The simple approach developed proved its suitability for quantifying the progress of irrigated schemes’ towards sustainability development as tested under the conditions of Gezira irrigated scheme in Sudan—the largest singly managed irrigation scheme in the world. The scheme was found to be sustainable under the condition that the crop yield is considered as the top priority; otherwise, the sustainability of the scheme is jeopardized. 相似文献
10.
Isiksal Aliya Zhakanova Samour Ahmed Resatoglu Nil Gunsel 《Environmental science and pollution research international》2019,26(20):20219-20231
Environmental Science and Pollution Research - This paper aims to explore the impact of real interest rates (RIN), income, trade, foreign direct investment (FDI), and energy consumption on... 相似文献