全文获取类型
收费全文 | 137篇 |
免费 | 2篇 |
国内免费 | 26篇 |
专业分类
安全科学 | 1篇 |
废物处理 | 6篇 |
环保管理 | 14篇 |
综合类 | 56篇 |
基础理论 | 21篇 |
污染及防治 | 46篇 |
评价与监测 | 11篇 |
社会与环境 | 7篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 1篇 |
2022年 | 10篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2015年 | 10篇 |
2014年 | 6篇 |
2013年 | 14篇 |
2012年 | 9篇 |
2011年 | 20篇 |
2010年 | 8篇 |
2009年 | 13篇 |
2008年 | 16篇 |
2007年 | 5篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1992年 | 2篇 |
排序方式: 共有165条查询结果,搜索用时 15 毫秒
151.
Yong-Zhong Wang Yan-Mei Wang Rong Chen Qiang Liao Xun Zhu 《International Journal of Green Energy》2015,12(10):1031-1036
In the present work, characteristics of ethanol production from a single particle composing of pretreated rice straw, cellulase, and β-glucosidase were invesitgated by simultaneous saccharification and fermentation (SSF). The experiment experienced a start-up stage for S. cerevisiae biofilm formation, which was operated at an initial pH value of 4.8 for yeast solution, culture temperature of 30°C, flow rate of 0.8 mL/min for yeast solution, and stably operating stage for ethanol production at a culture temperature of 30°C. Investigations found that the maximal ethanol yield of 9.7 mg/g and the biofilm thickness of 0.37 mm were obtained at 30 mL/min of carrier gas flow rate. Also, the optimal interval time of water supplement was 4 h for SSF. The results show that the appropriate gas flow rate and the interval time of water supplement can keep the high activities of biofilm and enzymes during SSF and result in a high ethanol yield. 相似文献
152.
Koarashi J Davis PA Galeriu D Melintescu A Saito M Siclet F Uchida S 《Journal of environmental radioactivity》2008,99(10):1671-1679
Carbon-14 ((14)C) is one of the most important radionuclides from the perspective of dose estimation due to the nuclear fuel cycle. Ten years of monitoring data on (14)C in airborne emissions, in atmospheric CO(2) and in rice grain collected around the Tokai reprocessing plant (TRP) showed an insignificant radiological effect of the TRP-derived (14)C on the public, but suggested a minor contribution of the TRP-derived (14)C to atmospheric (14)C concentrations, and an influence on (14)C concentrations in rice grain at harvest. This paper also summarizes a modelling exercise (the so-called rice scenario of the IAEA's EMRAS program) in which (14)C concentrations in air and rice predicted with various models using information on (14)C discharge rates, meteorological conditions and so on were compared with observed concentrations. The modelling results showed that simple Gaussian plume models with different assumptions predict monthly averaged (14)C concentrations in air well, even for near-field receptors, and also that specific activity and dynamic models were equally good for the prediction of inter-annual changes in (14)C concentrations in rice grain. The scenario, however, offered little opportunity for comparing the predictive capabilities of these two types of models because the scenario involved a near-chronic release to the atmosphere. A scenario based on an episodic release and short-term, time-dependent observations is needed to establish the overall confidence in the predictions of environmental (14)C models. 相似文献
153.
Jun Lu Lina JiangDingjiang Chen Koki ToyotaP. James Strong Hailong WangTadashi Hirasawa 《Agriculture, ecosystems & environment》2012,146(1):13-22
Anaerobic digestion has become increasing popular for managing biowastes in rural China as it has the advantage of generating biogas, a renewable energy. A new challenge, however, is minimizing the environmental pollution resulting from the anaerobically digested slurry (ADS). The aim of this study was to assess the feasibility of using a paddy field to remediate ADS while simultaneously cultivating rice. A field experiment was trialed using six treatments based on varying nitrogen loadings over the period of a rice-growing season. These treatments were adjusted to the content of the N within the ADS and had loadings of 270, 405, 540 and 1080 kg N ha−1. These treatments were compared to a negative control (no fertilizer) and a positive control (chemical fertilizer) that consisted of urea applied at 270 kg N ha−1. The effects of these N sources and slurry remediation were monitored using standard methods to measure water quality, soil properties and changes in rice production. Rice grain yields were generally higher for all ADS treatments than for the urea N treatment. Standing water quality in the field could reach national discharge standards for all treatments within 7-8 days after each ADS irrigation. Groundwater quality and heavy metal concentrations in both soil and the rice grain were not affected by the ADS treatments. We suggest that the quantities of ADS irrigated in 867-1734 m3 ha−1 was not only safe for food quality (rice grain) and the receiving environment (water and soil), but also beneficial to soil fertility and rice grain yield. 相似文献
154.
155.
I. H. Choi J. H. Choi S. H. Ko P. A. Moore Jr 《Journal of environmental science and health. Part. B》2013,48(5):432-435
This study was a pen trial in which the effects of adding different rates of liquid aluminum chloride (AlCl3) on litter pH, total volatile fatty acids (VFAs), and ammonia (NH3) fluxes was evaluated. Liquid AlCl3 treatments used in this study were sprayed on the rice hull surface at rates of 100 g, 200 g, and 300 g liquid AlCl3/kg rice hulls; untreated rice hulls served as controls. Litter pH, total VFAs, and NH3 fluxes were all lowered (P< 0.05) by all of the liquid AlCl3 treatments compared with controls during certain times of the 5 week study. However, there were no significant differences among treatments on litter pH at the end of the study (from 3 to 5 weeks) or NH3 fluxes at beginning of the study (0 to 3 weeks). Total VFAs were reduced 16 %, 29 %, and 53 % by 100 g liquid AlCl3/kg rice hulls, 200 g liquid AlCl3/kg rice hulls, and 300 g liquid AlCl3/kg rice hulls, respectively. Liquid AlCl3additions reduced NH3 fluxes by 35 %, 57 % and 67 %, respectively, at the low, medium and high rates. In summary, these results indicate that adding liquid aluminum chloride to rice hulls would be a useful tool in reducing the negative environmental impact of poultry litter. It should be noted that the decreased VFA production and NH3 volatilization was chiefly associated with reduction in litter pH. 相似文献
156.
M. A. Gomarasca 《Environmental monitoring and assessment》1996,41(2):159-170
The special project RAISA (Advanced Researches for Innovation in Agricultural Systems) of the National Research Council of Italy concerns the development of new methodologies for the study and evaluation of the impact of agrotechnologies on the environment. In the project, several trans-disciplinary Units have worked together since 1990. The aim of the project is to define systems, using tools such as remote sensing and Geographical Information Systems, for decision making support in land planning and land use management, with particular attention to groudwater table pollution. The fundamental steps for evaluation of the impact of agrotechnologies on the Po river watershed, 75,000 km2 in northern Italy, and Tevere (Tiber) river watershed, 17.169 km2 in Central Italy are described here. The study concerns particular areas located in the western part of the Po River plain, where flooded rice is the main crop, and in the central plain of the Tevere basin where the risk of water pollution is considerable, due to small and medium sized swine breeding farms. The aspects considered were water pollution due to mineral nitrogen used to fertilize the rice crop and the nitrogen contained in the waste water from pig farms. For the Po river basin the methodology developed was based on the integration of satellite remote sensing images, and the available cartography, such as topographic and thematic maps, together with the hydrological and the toxicological data of the chemical fertilizers employed, summarized in maps of the groundwater table pollution hazard. A simpler evaluation was obtained in the Tevere river basin: the thematic layers were crossed in bi-directional matrices and the result merged with the map of the territorial distributionof the swine. In both cases the selected information was integrated and processed in Integrated sub-basin scale. The GISs led to the development of a user-friendly system for formalizing our knowledge of the degree of pollution hazard in simple and readable maps.Research supported by National Research Council of Italy, Special Project RAISA, sub-project N. 1 Paper N. 相似文献
157.
158.
根据IPCC Guidelines(1995)提供的方法,对1990年江浙沪地区水稻田的CH4排放统计计算,并所得数据进行评估和分析。通过计算得到江浙沪地区水稻田CH4排放为1.77Tg,占总CH4排放的53.6%,提出了该地区减少水稻田CH4排放的措施。 相似文献
159.
通过实地调查,初步弄清水稻受大气污染后,其产量损失与大气污染程度的关系,调查结果显示,水稻受大气污染后,其每穗实粒数,结实率与大气污染程度呈反比,而产量损失率与大气污染程度呈正比,产量损失率与大气污染程度的相关系数达极显著水平。 相似文献
160.
In much of sub-Saharan Africa (SSA), the lack of organic soil amendments constitutes one of the principal causes for declining soil fertility in intensifying farming systems. The challenge, therefore, remains to increase the availability of organic inputs and to develop recommendations for their combination with inorganic fertilizers. An on-farm experiment was conducted in the northern Guinea savanna of Nigeria to evaluate the fertilizer effect of rice (Oryza sativa L.) mill waste (RMW) on a degraded Alfisol. The decomposition and nutrient (N and P) release patterns of RMW were studied using the litterbag technique, and the effect on maize yield and soil properties was determined. The RMW was applied at rates of 0, 5, 10, and 15 Mg DM ha−1 and was applied either unburnt or burnt (farmers’ practice). In both years, compound fertilizer was broadcast during land preparation on all plots at rates of 40 kg N ha−1, 17 kg P ha−1, and 33 kg K ha−1.Results obtained in the litterbag study showed that, at maize harvest, more than 90% of the P had been released from the decomposing RMW. However, around 60% of the organic C and 45% of the N still remained. Compared to the control treatment (0 Mg ha−1 RMW), which yielded 0.55 Mg ha−1, maize (Zea mays L.) grain yields were increased by 95% when 10 Mg ha−1 of unburnt RMW was applied, and by 147% with 15 Mg ha−1 (mean of 2 years). In contrast, burnt RMW did not result in significant yield increases. The cumulative application of 30 Mg ha−1 of unburnt RMW significantly increased the soil organic carbon in the surface soil from 0.7% (0 Mg ha−1 RMW) to 1.3%.The results of this investigation indicate that RMW constitutes a valuable organic input in the Guinea savanna if applied unburnt at rates of 10–15 Mg ha−1 in combination with inorganic fertilizer. The repeated application of unburnt RMW may contribute to the rehabilitation of degraded soils through the buildup of soil organic matter. 相似文献