全文获取类型
收费全文 | 769篇 |
免费 | 16篇 |
国内免费 | 108篇 |
专业分类
安全科学 | 36篇 |
废物处理 | 32篇 |
环保管理 | 76篇 |
综合类 | 347篇 |
基础理论 | 80篇 |
污染及防治 | 227篇 |
评价与监测 | 78篇 |
社会与环境 | 14篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 10篇 |
2022年 | 12篇 |
2021年 | 28篇 |
2020年 | 21篇 |
2019年 | 16篇 |
2018年 | 15篇 |
2017年 | 17篇 |
2016年 | 22篇 |
2015年 | 26篇 |
2014年 | 31篇 |
2013年 | 46篇 |
2012年 | 43篇 |
2011年 | 74篇 |
2010年 | 37篇 |
2009年 | 51篇 |
2008年 | 51篇 |
2007年 | 44篇 |
2006年 | 45篇 |
2005年 | 33篇 |
2004年 | 26篇 |
2003年 | 39篇 |
2002年 | 26篇 |
2001年 | 23篇 |
2000年 | 31篇 |
1999年 | 17篇 |
1998年 | 21篇 |
1997年 | 21篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 14篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 2篇 |
1987年 | 1篇 |
1985年 | 2篇 |
1982年 | 1篇 |
排序方式: 共有893条查询结果,搜索用时 31 毫秒
881.
Reaction kinetics is fundamental for modelling the thermal oxidation of a solid phase, in processes such as dust explosions, combustion or gasification. The methodology followed in this study consists in i) the experimental identification of the reaction mechanisms involved in the explosion of organic powders, ii) the proposal of simplified mechanisms of pyrolysis and oxidation, iii) the implementation of the model to assess the explosion severity of organic dusts. Flash pyrolysis and combustion experiments were carried out on starch (22 μm) and cellulose (53 μm) at temperatures ranging from 973 K to 1173 K. The gases generated were collected and analyzed by gas chromatography. In this paper, a semi-global pyrolysis model was developed for reactive systems with low Damköhler number. It is in good agreement with the experimental data and shows that both carbon monoxide and hydrogen are mainly generated during the pyrolysis of the solid, the generation of the latter compound being greatly promoted at high temperature. A simplified combustion model was also proposed by adding two oxidation reactions of the pyrolysis products. In parallel, flame propagation tests were performed in a semi open tube in order to assess the burning velocity of such compounds. The laminar burning velocity of cellulose was determined to be 21 cm s−1. Finally, this model will be integrated to a predictive model of dust explosions and its validation will be based on experimental data obtained using the 20 L explosion sphere. The explosion severity of cellulose was determined and will be used to develop and adjust the predictive model. 相似文献
882.
883.
Zhijie Li Lu Lei Yanpei Li Chun Chen Qingqing Wang Wei Zhou Jiaxing Sun Conghui Xie Yele Sun 《环境科学学报(英文版)》2021,33(6):242-252
Extensive studies on aerosol chemistry have been carried out in megacities in China, however, aerosol characterization in Central China Plain (CCP) is limited. Here we conducted real-time measurements of fine particle composition with a time-of-flight aerosol chemical speciation monitor in Kaifeng, Henan province in October 2019. Our results showed that nitrate and organics constituted the major fraction of non-refractory PM2.5 for the entire study, on average accounting for 34% and 33%, respectively. However, aerosol composition was substantially different among four periods due to different meteorological conditions and chemical processing. For instance, nitrate presented the lowest contribution during the first period due to evaporative loss associated with high temperature (T), and then rapidly increased during polluted periods as a function of relative humidity (RH). Positive matrix factorization analysis showed the dominance of secondary organic aerosol (SOA) in OA, and also the changes in OA composition under different T and RH levels. In addition, this study is unique with two periods of local emission controls. Back trajectory and coefficient of divergence analysis showed that air pollution in CCP was overall homogeneously distributed. As a result, the effectiveness of local emission controls in this region was strongly affected by meteorological conditions and regional transport. We found that one of the periods with emission control even showed the highest concentrations for the entire study. Our results point towards the limited effect of local emission controls in mitigating air pollution in CCP, and highlight the importance of joint emission controls under unfavorable meteorological conditions. 相似文献
884.
Sara Evangelisti Paola Lettieri Domenico Borello Roland Clift 《Waste management (New York, N.Y.)》2014,34(1):226-237
Particularly in the UK, there is potential for use of large-scale anaerobic digestion (AD) plants to treat food waste, possibly along with other organic wastes, to produce biogas. This paper presents the results of a life cycle assessment to compare the environmental impacts of AD with energy and organic fertiliser production against two alternative approaches: incineration with energy production by CHP and landfill with electricity production. In particular the paper investigates the dependency of the results on some specific assumptions and key process parameters. The input Life Cycle Inventory data are specific to the Greater London area, UK. Anaerobic digestion emerges as the best treatment option in terms of total CO2 and total SO2 saved, when energy and organic fertiliser substitute non-renewable electricity, heat and inorganic fertiliser. For photochemical ozone and nutrient enrichment potentials, AD is the second option while incineration is shown to be the most environmentally friendly solution. The robustness of the model is investigated with a sensitivity analysis. The most critical assumption concerns the quantity and quality of the energy substituted by the biogas production. Two key issues affect the development and deployment of future anaerobic digestion plants: maximising the electricity produced by the CHP unit fuelled by biogas and to defining the future energy scenario in which the plant will be embedded. 相似文献
885.
Satnam Singh Li-Sen Young Fo-Ting Shen Chiu-Chung Young 《Waste management (New York, N.Y.)》2014,34(10):1877-1883
Discharging untreated highly acidic (pH < 4.0), organic and nutrients rich monosodium glutamate wastewater (MW), and highly alkaline (pH > 10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5 ± 0.1) with PW and lime (treatments represented as MW + PW and MW + Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha?1. Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear?1 and 100-kernel weight were higher in MW + Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW + Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW + PW. The MW + PW and MW + Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances. 相似文献
886.
Mathieu Muller Julie Jimenez Maxime Antonini Yves Dudal Eric Latrille Fabien Vedrenne Jean-Philippe Steyer Dominique Patureau 《Waste management (New York, N.Y.)》2014,34(12):2572-2580
The design and management of anaerobic digestion of sewage sludge (SS) require a relevant characterisation of the sludge organic matter (OM). Methods currently used are time-consuming and often insufficiently informative. A new method combining chemical sequential extractions (CSE) with 3D fluorescence spectroscopy was developed to provide a relevant SS characterisation to assess both OM bioaccessibility and complexity which govern SS biodegradability. CSE fractionates the sludge OM into 5 compartments of decreasing accessibility. First applied on three SS samples with different OM stability, fractionation profiles obtained were in accordance with the latter. 3D fluorescence spectroscopy revealed that the bioaccessible compartments were mainly constituted of simple and easily biodegradable OM while the unaccessible ones were largely made of complex and refractory OM. Then, primary, secondary and anaerobically digested sludge with different biodegradabilities were tested. Complexity revealed by 3D fluorescence spectroscopy was linked with biodegradability and chemical accessibility was correlated with sludge bioaccessibility. 相似文献
887.
Davide Papurello Andrea Lanzini Pierluigi Leone Massimo Santarelli Silvia Silvestri 《Waste management (New York, N.Y.)》2014,34(11):2047-2056
The present work investigates electricity production using a high efficiency electrochemical generator that employs as fuel a biogas from the dry anaerobic digestion of the organic fraction of municipal solid waste (OFMSW).The as-produced biogas contains several contaminants (sulfur, halogen, organic silicon and aromatic compounds) that can be harmful for the fuel cell: these were monitored via an innovative mass spectrometry technique that enables for in-line and real-time quantification.A cleaning trap with activated carbons for the removal of sulfur and other VOCs contained in the biogas was also tested and monitored by observing the different breakthrough times of studied contaminants.The electrochemical generator was a commercial Ni anode-supported planar Solid Oxide Fuel Cell (SOFC), tested for more than 300 h with a simulated biogas mixture (CH4 60 vol.%, CO2 40 vol.%), directly fed to the anode electrode. Air was added to promote the direct internal conversion of CH4 to H2 and CO via partial oxidation (POx).The initial breakthrough of H2S from the cleaning section was also simulated and tested by adding ~1 ppm(v) of sulfur in the anode feed; a full recovery of the fuel cell performance after 24 h of sulfur exposure (~1 ppm(v)) was observed upon its removal, indicating the reliable time of anode exposure to sulfur in case of exhausted guard bed. 相似文献
888.
Jianbin Guo Renjie Dong Joachim Clemens Wei Wang 《Waste management (New York, N.Y.)》2013,33(11):2219-2224
Many Chinese biogas plants run in the lower range of mesophilic conditions. This study evaluated the performance of a completely stirred anaerobic reactor treating pig manure at different temperatures (20, 28 and 38 °C). The start-up phase of the reactor at 20 °C was very long and extremely poor performance was observed with increasing organic loading rate (OLR). At an OLR of 4.3 g ODM L?1 d?1, methane production at 28 °C was comparable (3% less) with that at 38 °C, but the risk of acidification was high at 28 °C. At low OLR (1.3 g ODM L?1 d?1), the biogas process appeared stable at 28 °C and gave same methane yields as compared to the reactor operating at 38 °C. The estimated sludge yield at 28 °C was 0.065 g VSS g?1 CODremoved, which was higher than that at 38 °C (0.016 g VSS g?1 CODremoved). 相似文献
889.
Muhammad Asim Ibrahim Görgen Göransson Fabio Kaczala William Hogland Marcia Marques 《Waste management (New York, N.Y.)》2013,33(11):2296-2306
In this study temporary storage sites of municipal solid waste were characterized based on their potential social, health and environmental impacts as a consequence of spontaneous fires, by employing Boolean as well as weighted-linear-combination approaches in connection with various fuzzy set functions of population density around the storage sites. Sweden was used as the case study and data from 105 storage sites were analysed; of these, 38 were identified to be posing high risk for downwind residing population. Furthermore, during the past 10 years, the fire frequency and the average population residing within a radius of 1, 2, and 3 km were found to be comparatively higher for storage sites owned by private companies than for those owned by municipalities. The study provided first-cut information of poorly sited temporary storage sites and can help in formalizing the comprehensive risk analysis in the future. 相似文献
890.
The aim of this work was to examine the performance of a sand filter in treating modern olive mill (OMW) effluents after dilution with domestic wastewater on a one-to-one basis. The experimental pilot consisted of a column of opaque PVC, and the sand filter was filled with 50 cm of sand and 10 cm of gravel in the top and the bottom of the filter. The alimentation (4 cm/day) was done sequentially following a 1 day wet/3 days dry cycle. The OMW effluent was very acidic with a pH of 4.12, and had high concentrations of phenolic compounds (7.2 g/L) and total chemical oxygen demand (65 g/L). The percolation of the diluted OMW through the sand filters caused an increase in pH from 4.84 to 8.25 and a 90% removal of total suspended solids. The sand filter treatment also led to important reductions in organic matter (90% of total COD, 83% of dissolved COD and 92% of phenolic compounds) and nutrients (91% of Kjeldahl-nitrogen, 97% of ammonia-nitrogen, 99% of nitrate-nitrogen and 99% of phosphates). The flow rate became very low indicating clogging of the sand pores after 10 weeks. HPLC analysis of the diluted OMW before and after passage through the sand filter showed an important reduction in the toxic monomeric compounds after the treatment. 相似文献