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高速铁路客运车站气力垃圾收集输送系统应用研究 总被引:1,自引:0,他引:1
近年来国内高速铁路发展迅猛,同时也新建了一些高速铁路车站,但目前国内铁路车站站车垃圾仍然采用原始的人工收集或者人工机械混合收集的方式,这些传统的垃圾收集方式影响城市形象及人身健康。气力垃圾收集输送系统是目前国际最为先进的垃圾收集输送系统,文章对该系统在高速铁路车站的应用进行了研究,提出了具体的实施方案。 相似文献
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市售绿茶自混合水溶液中吸附除去铬(Ⅵ)的研究 总被引:9,自引:0,他引:9
本文探讨了国产茶叶(市售云南产绿茶)的结构、成份和溶解,以及在不同浓度、时间、pH、温度的条件下,自混合溶液中大量吸附铬(Ⅵ)的特性。结果表明,浸泡过的茶叶对Cr(Ⅵ)的吸附率略低于未泡茶样,在一定条件下,Cr(Ⅵ)的吸附量可达到4.96mg/g。我们建议在这复杂体系中,用离子交换吸附过程形成表面配合物,以及发生化学作用的综合吸附机理来解释。 相似文献
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Zhuobiao M Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue Di Zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu 《环境科学学报(英文版)》2019,31(5):121-134
Air concentrations of volatile organic compounds (VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and 9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most (36.15%) to the total propene-equivalent concentration of the measured VOCs, followed by combustion emission (16.92%), vegetation emission and secondary formation (14.33%), solvent usage (10.59%), petrochemical industry emission (9.89%), petrol evaporation (6.28%), and liquefied petroleum gas (LPG) usage (5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics, e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O3 pollution in Shenyang. 相似文献
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M. Hein S. Rotter M. Schmitt-Jansen P. C. von der Ohe W. Brack E. de Deckere C. Schmitt D. de Zwart L. Posthuma E. M. Foekema I. Muñoz S. Sabater H. Segner E. Semenzin A. Marcomini J. van Gils B. van Hattum L. A. van Vliet 《Environmental Sciences Europe》2010,22(3):217-228
The EU Water Framework Directive (WFD) requires the achievement of good ecological and chemical status in European river basins. However, evidence is increasing that a majority of European water bodies will not achieve this goal. Nutrient emissions and related eutrophication together with hydromorphological alterations have been suggested as the major driving forces of this insufficient ecological status. MODELKEY (511237 GOCE, FP6) provides strong evidence that toxic chemicals also affect the ecological status of European rivers. This was demonstrated in the case study rivers Elbe, Scheldt and Llobregat on different scales. This paper summarises key findings of MODELKEY including recommendations for WFD implementation. We ? provide evidence of toxic stress in aquatic ecosystems, ? provide evidence that impairment of ecological status results from impact of multiple stressors, ? suggest a tiered approach to assess impact of chemicals on ecological status, ? suggest a new approach for deriving candidate compounds for monitoring and prioritisation, ? call for consideration of bioavailability and bioaccumulation in chemical status assessments, ? suggest improvements for WFD water quality monitoring programmes, ? provide new integrated tools for basin-scale risk assessment and decision making, ? developed a Decision Support System to support river basin management. These key results will be presented in a series of ten integrated sections; for the scientific details please refer to publications listed on the MODELKEY website (http://www.modelkey.org/). This article also looks beyond MODELKEY and proposes a combination of MODELKEY diagnostic tools with recent ecological methods to further improve effectiveness of river basin management. 相似文献
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The reductive degradation of nitrobenzene (NB) by zero-valent iron was investigated. Experimental results showed that the degradation of NB was influenced by pH and NB concentration. The optimum pH value was found to be 3.0 for the reductive degradation of NB in the tested pH ranges of 3.0-12.0. The formation rate of aniline, a major reductive product of NB, followed zero-order kinetics at various pH levels. Furthermore, GC/MS analysis showed that aniline, azobenzene and azoxybenzene were the reductive products of NB by zero-valent iron. With the analysis of the products with GC/MS and FTIR, possible reductive pathways of NB by zero-valent iron were suggested. 相似文献
580.
通过室内循环冻融循环试验和三轴不固结不排水(UU)压缩试验研究了循环冻融作用与细砾组含量(P_(2-5))对黏质粗粒土抗剪性能的影响。结果表明,冻融循环作用对黏质粗颗粒土的应力—应变曲线性状具有一定的影响,可使其由未冻融的应变软化向应变硬化转变的趋势,但随着细砾组P_(2-5)含量的增加,冻融作用对其影响逐渐减弱。随着冻融循环次数的增加,土样剪切强度呈现逐渐衰减,且在5~9次冻融循环次数后基本保持不变,多次循环冻融作用后剪切强度最大衰减幅度可达40%。弹性模量随冻融循环次数的增加上下波动较大但整体呈现下降趋势。在抗剪强度指标方面,冻融作用对黏聚力影响比较显著,随着冻融循环次数的增加,黏聚力逐渐减小,最大衰减幅度可达65%,而内摩擦角上下波动较大无明显趋势。此外,随着细砾组P_(2-5)含量的增加,剪切强度、弹性模量及抗剪强度指标均呈现不同程度的减小,这与粗粒土内部粗颗粒和细颗粒占比及其强度发挥机制有关。 相似文献