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71.
为降低某公司烧结机干法脱硫装置烟道阻力,减少引风机出力,实现节能优化,运用计算流体力学软件,对引风机出口烟道内流场进行三维数值模拟,并根据分析结果进行烟道的优化改造。改造后,吸收塔入口负压由-200Pa提升至-560Pa,风机电流由328A降为301.4A,节能降耗显著。  相似文献   
72.
中国2030年CO2排放总量预测研究   总被引:2,自引:0,他引:2  
我国2005年和2010年CO2排放总量分别为55亿t和81.52亿t,“十五”和“十一五”期间年均增长率分别为11.0%和8.0%.中国2011-2015年、2016-2020年、2021-2025年和2026-2030年GDP年均增长率分别为8%、7%、6%、5%的经济发展模式与对应的能源消费弹性系数分别为0.5、0.5、0.4和0.3的能源发展模式,预测2030年燃煤、燃油和天然气CO2排放量及全国CO2排放总量.提出减少CO2排放总量对策,主要包括:调整能源结构,尽量减少煤炭消费量占能源消费总量的比例,增加石油、天然气和新能源的比例,提高CO2综合利用率,完善CO2管理政策与法律法规等.  相似文献   
73.
Contaminated food through dietary intake has become the main potential risk impacts on human health. This study investigated concentrations of rare earth elements (REEs) in soil, vegetables, human hair and blood, and assessed human health risk through vegetables consumption in the vicinity of a large-scale mining area located in Hetian Town of Changting County, Fujian Province, Southeast China. The results of the study included the following mean concentrations for total and bio-available REEs of 242.92 ± 68.98 (135.85–327.56) μg g−1 and 118.59 ± 38.49 (57.89–158.96) μg g−1 dry weight (dw) in agricultural soil, respectively, and total REEs of 3.58 ± 5.28 (0.07–64.42) μg g−1 dw in vegetable samples. Concentrations of total REEs in blood and hair collected from the local residents ranged from 424.76 to 1274.80 μg L−1 with an average of 689.74 ± 254.25 μg L−1 and from 0.06 to 1.59 μg g−1 with an average of 0.48 ± 0.59 μg g−1 of the study, respectively. In addition, a significant correlation was observed between REEs in blood and corresponding soil samples (R2 = 0.6556, p < 0.05), however there was no correlation between REEs in hair and corresponding soils (p > 0.05). Mean concentrations of REEs of 2.85 (0.59–10.24) μg L−1 in well water from the local households was 53-fold than that in the drinking water of Fuzhou city (0.054 μg L−1). The health risk assessment indicated that vegetable consumption would not result in exceeding the safe values of estimate daily intake (EDI) REEs (100−110 μg kg−1 d−1) for adults and children, but attention should be paid to monitoring human beings health in such rare earth mining areas due to long-term exposure to high dose REEs from food consumptions.  相似文献   
74.
Urban sprawl is a major issue for sustainable development. It represents a significant contribution to energy consumption of a territory especially due to transportation requirements. However, transport energy consumption is rarely taken into account when the sustainability of suburban structures is studied. In this context, the paper presents a method to estimate transport energy consumption in residential suburban areas. The study aimed, on this basis, at highlighting the most efficient strategies needed to promote awareness and to give practical hints on how to reduce transport energy consumption linked to urban sprawl in existing and future suburban neighborhoods. The method uses data collected by using empirical surveys and GIS. An application of this method is presented concerning the comparison of four suburban districts located in Belgium to demonstrate the advantages of the approach. The influence of several parameters, such as distance to work places and services, use of public transport and performance of the vehicles, are then discussed to allow a range of different development situations to be explored. The results of the case studies highlight that traveled distances, and thus a good mix between activities at the living area scale, are of primordial importance for the energy performance, whereas means of transport used is only of little impact. Improving the performance of the vehicles and favoring home-work give also significant energy savings. The method can be used when planning new areas or retrofitting existing ones, as well as promoting more sustainable lifestyles regarding transport habits.  相似文献   
75.
Sustainable product development is closely related to sustainable consumption. The understanding of consumers' purchase, use and discard behaviours may facilitate the identification of requirements to guide manufacturers in the development of sustainable goods and services. The aim of this paper is to investigate consumers' perception about factors that motivate or discourage the consumption of sustainable products to identify demands and convert them into requirements. South Brazilian green and traditional consumers were asked to complete an exploratory qualitative questionnaire. Their answers were organized and compared to identify differences and similarities between the demands of these two groups. Furthermore, demands were converted into requirements for packages, products, manufactures, stores planning and discard systems. The interpretation of factors that motivate or discourage the purchase of sustainable products given by interviewees led to the creation of a list of possible public policies or programmes, aiming to support sustainable consumption. The results demonstrate the necessity of further quantitative investigation between consumer groups, for validation purposes.  相似文献   
76.
电解法处理含镍废水及纯镍的回收   总被引:1,自引:0,他引:1  
采用电解回收法处理Ni2+含量为2g/L的废水,在阴极回收纯镍。研究了电解电流、极距、NH4Cl浓度、pH值等因素对Ni2+去除率、槽压、阴极能耗的影响,得出最优工艺参数为:温度20℃,电解时间20min时、电解电流300mA,极距15mm,NH4Cl浓度5g/L,pH值8.0,该条件下Ni2+去除率为96.926%,槽压16.21V,阴极能耗22.418kW.h/kg,在阴极可得到沉积6.45μm厚的镍板。  相似文献   
77.
The premise of this article is that the planning and design of new rest camps in conservation areas should be based on ecological principles in such a way that the plant ecology within the camp be an integral part and extension of the natural ecology of its immediate vicinity. This is desirable so that visitors to the camp will be provided not only with facilities for resting, eating, and sleeping, but also be able to enjoy and study the natural environment in a relaxed atmosphere. The Berg-en-Dal rest camp, which was established in Kruger National Park, was planned in such a way and designed according to the principles outlined by the authors in a companion article. The planning included six zones: a control zone, day visitor zone, overnight visitor zone, staff accommodation zone, recreation zone, and service zone. The point is stressed that plant species selected to be used as additional vegetation to those already growing in the camp were endemic to the nine landscape facets identified in the camp. The design allowed for separation of the various land-use zones in such a way that they would complement each other rather than be a hindrance to each other. The camp has been built according to the plans included in this article and has proved to be a great success. The conclusion is drawn that the planning principles are sound and should be used in the future for the planning and design of rest camps for conservation areas in South Africa.  相似文献   
78.
Large but feasible increases that have been projected for the production of wood energy in the United States can be expected to significantly alter the current carbon storage patterns in US forest vegetation. The 1976 net wood increment left after forest cutting equals about 136 × 106 tons of carbon/year, with about 60% of the increment found in merchantable trees, and the remainder in nonmerchantable components.Achieving 5–10 quads of wood energy beyond 1976 levels by the year 2010 can significantly change current carbon storage patterns with the magnitude of change dependent on the extent of residue harvest to meet energy goals, and the rate of future forest growth. Complete loss of the apparent net wood increment is a possible outcome.Although the future growth and harvest situation cannot be known now, a range of possible scenarios suggests that US forests in the year 2010 will store much less carbon than today, thus significantly changing their role in the global carbon cycle.  相似文献   
79.
瓦勃氏呼吸仪测定乐果合成废水的可生化性   总被引:1,自引:0,他引:1  
张本兰  裴健 《四川环境》1992,11(2):16-18,26
本文概述了瓦勃氏呼吸仪测定有机污染物的可生化性的基本原理和方法。通过测定用乐果合成废水驯化后的微生物的生化呼吸线和相对耗氧速度曲线,结果表明:乐果合成废水是有毒的,但是完全可以被特异驯化后的微生物所降解;其降解速度与时间和废水所含污染物的浓度有关。  相似文献   
80.
海岸带环境资源综合管理,是对海岸带资源可持续开发利用模式下的现代综合管理。本文在对区域海岸带环境资源综合管理的内涵及管理目标进行分析的基础上,以秦皇岛海岸带环境资源实施综合管理为例,提出了区域海岸带环境资源综合管理的评价过程及模式。  相似文献   
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