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991.
Du Xile 《中国人口.资源与环境(英文版)》2013,11(4):44-51
Abstract Water pollution is one of the major environmental problems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central China has become a serious problem for its development. In this study, the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI), and the change trend was calculated using methods of Mann-Kendall test and Sen’s slope estimator, based on the monitoring data from 1998 to 2008. The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases, implying that most rivers were seriously polluted. However, this serious polltuon is expected to be gradually improved, as the concentration of water pollutants and NCPI declined significantly in most rivers. Water pollution in reservoirs was much lower than rivers, and the NCPI in the three monitored reservoirs was lower than 3 in most years, and shows a downward trend. Although the surface water quality was gradually improved, great efforts are still needed to enhance the protection and improvement of surface water environment. 相似文献
992.
《International Journal of Sustainable Engineering》2013,6(3):258-266
This paper reveals comparative experimental analysis of the effect of variation of natural and forced convection heat losses on the performance of prototype parabolic dish water heater with coated and non-coated receivers. With the above-described system, hot water needs in domestic applications can be fulfilled instantly. A parabolic dish collector was used for instant water heating. Design of solar parabolic dish collector consists of truncated cone-shaped helical coiled receiver made up of copper at focal point. Instantaneous efficiency of 63% and 48% has been achieved with coated and non-coated receivers. This prototype has been evaluated for its performance with water flow rate of 0.0076 kg/s during the months of April and May 2010 at Shivaji University, Kolhapur, Maharashtra, India (latitude: 16.42° North, longitude: 74.13° West). 相似文献
993.
《International Journal of Sustainable Engineering》2013,6(4):278-286
Sustainable innovation represents a current challenge for companies, as firms need to change the way they design, develop, produce and distribute products and services. Therefore, this paper proposes a new framework to be used as a reference guideline for organisations to define a roadmap, specific actions and projects to achieve sustainable innovation, integrating four key enablers. The first enabler is mass customisation (MC), which targets the identification and compliance with customers' specific needs and requirements in order to achieve customer‐driven design. At the same time, the sustainable development (SD) paradigm is taken into consideration, where for any new product or service, companies analyse the benefits, risks and impacts of not only economic factors, but also social and environmental implications. The third enabler is linked to the value network (VN), where innovations happen owing to the active collaboration and distributed knowledge of partners inside and outside the company. Finally, the fourth and last considers the complete product and service life cycle (PSLC), where the three sustainable elements are identified and analysed in each single business process. Two case studies, (footwear sector and water treatment plants) are described to show the validity and successful deployment of the proposed framework in real industrial scenarios. 相似文献
994.
《International Journal of Sustainable Engineering》2013,6(1):66-73
Current carbon footprinting (CF) and life cycle assessment (LCA) methods do not treat recycled biogenic carbon adequately, because the calculation rules for recycled products and biogenic carbon stored in products are defined independently from each other. Therefore, an improved and consistent calculation rule for the CF of product systems containing both recycling processes and carbon stored in products is proposed. The methodological approach consists of the application of the same allocation principles for both greenhouse gas (GHG) releases and GHG removals: (1) explicit accounting of inputs (GHG removals) and outputs (GHG releases) of biogenic carbon flows instead of assuming carbon neutrality per se; (2) consistent application of allocation rules for environmental benefits and environmental burdens. It is shown that the different modelling approaches (e.g. polluter pays, conservative or partitioning) lead to different results in LCA and CF calculations, e.g. the GHG emissions of first life cycle of the product system calculated here range between ? 1.6 units in the polluter pays approach and 4 units in the conservative approach. It is shown that the currently common modelling is an average approach for primary biogenic material, a worst-case approach for recycled biogenic material and a best-case approach for disposed biogenic material. This paper proposes to improve the currently developed standards for CF by adding a requirement to the goal and scope definition phase that ensures the consistent and transparent documentation, how biogenic carbon removal credits are allocated between life cycles. 相似文献
995.
《International Journal of Sustainable Engineering》2013,6(3):224-235
Reliable prediction of total product life cycle costs is crucial for the life cycle management of products. These costs are predominantly dictated by the actual operational behaviour of the product's lifetime, and cannot be sufficiently determined through deterministic calculations due to the stochastic and the dynamic nature of the problem. This is specifically true when considering running systems with unknown lifetime and operation parameters. Against this background, the paper presents a dynamic methodology for predicting life cycle costs based on product failure mechanisms, their associated critical lifetime prediction parameters and optional maintenance strategies to enable decision support for product design and use phase strategies. 相似文献
996.
天津近海富营养化及环境因子的时空变化特征 总被引:2,自引:1,他引:1
基于1995—2010年监测数据,通过Mann-Kendall趋势检验和Kriging空间插值等方法,对天津近岸海域氮磷营养盐、有机污染物和富营养状况的时空变化趋势及其成因进行了分析. 结果表明:在天津近岸海域的48个监测时段中,有81.3%的监测时段处于富营养状态,有39.6%的ρ(DIN)和16.7%的ρ(DIP)超过海洋水质四类标准,有89.6%的ρ(CODMn)符合海洋水质一类标准;氮和磷为主要污染物,污染物质量浓度和富营养状态的季节性差异显著. ρ(DIP)、ρ(CODMn)和营养状态指数的年际变化主要呈下降趋势,ρ(DIN)呈先下降后显著上升的趋势;ρ(DIN)、ρ(DIP)和ρ(CODMn)在空间分布上基本遵循近岸高、远岸低的规律,其中ρ(DIN)和ρ(DIP)均显著呈带状分布,并且基本为北高南低. 防治天津近岸海域水体富营养化的关键是削减丰水期和平水期入海径流的氮负荷以及北部海域入海径流的磷负荷. 相似文献
997.
为回收废弃LCD(液晶显示器)显示屏中的液晶,提出了“超声波辅助有机溶剂溶解液晶屏、膜过滤和减压蒸馏”的回收方法,并以TN-TFT显示模式的液晶屏为试验对象,对回收液晶的光电性能进行检测和相变分析,以评估其潜在的利用价值. 结果表明:方法的回收率达50%;收集物液晶特性明显,呈现出较宽的向列相温变区间和较高的清亮点温度,但纯度不高,达不到日常显示所用的液晶纯度要求(GCMS>99%);响应时间为33.2ms,可以满足日常LCD显示屏的要求;介电常数为4.71,折射率为0.089,虽与纯净液晶相比稍有下降,但可满足标准AM-LCD显示的参数要求;阈值电压为3.2V,比纯净液晶有所提高,可进一步去除离子性杂质进行提纯,以降低阈值电压. 相似文献
998.
茶园土壤氮素组分变化影响茶园土壤供氮能力和氮素循环.以植茶30、50和70 a的茶园土壤为研究对象,探讨不同植茶年限土壤氮素组分变化特征及其与理化性质和酶活性之间的关系.结果表明:①随着植茶年限的增加,粉粒、全磷、脲酶和过氧化氢酶活性逐渐增加,砂粒、黏粒、pH、电导率、有机碳和蔗糖酶活性逐渐降低,碱性磷酸酶活性先增加后降低,土壤含水量和酸性磷酸酶活性无显著变化.②随着植茶年限的增加,酸解性铵态氮、氨基酸态氮和硝态氮含量显著增加,且茶园土壤全氮、酸解性铵态氮、未知态氮和非酸解氮含量显著高于林地.③全磷、碱性磷酸酶和脲酶是土壤氮素组分变化的主要影响因子.其中,有机氮组分与全磷、碱性磷酸酶活性具有显著相关性,无机氮组分与碱性磷酸酶活性具有显著相关性,全氮与砂粒、粉粒、全磷、脲酶和碱性磷酸酶活性具有极显著的相关性. 相似文献
999.
1000.
采用生命周期评价(LCA)法研究了塑料牛奶包装的全生命周期环境影响,并在处置阶段对不同处置方式的环境影响进行比较.通过现场和资料调研的方式,获得所有生命周期阶段能量物质的输入/输出和环境外排数据.结果表明:塑料牛奶包装生命周期阶段中环境影响比重最大的是原料获取阶段,占90%以上.其全生命周期环境影响主要集中在化石燃料、无机物对人体损害和气候变化3个方面,在致癌、酸化富营养化和生态毒性方面影响稍小.3种处置方式对环境影响由大到小依次为填埋>焚烧>再生,其中填埋和焚烧处置分别比塑料包装处置阶段前的环境影响增加16.1%和5.3%,再生可降低75.9%. 相似文献