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61.
高效能源利用是推动工业发展,进而促使城镇格局演化的重要催化剂,同时城镇化的高速发展对工业能源的消费结构和利用效率提出了进一步的要求,这必将影响到低碳城市建设和环境保护等生态责任目标的实现。选取2003—2012年长江经济带11个省份(直辖市)的相关数据,运用门槛模型对城镇化率、城镇居民人均总收入、能源工业投资、工业总产值、城市人口密度、产业结构等影响工业能源消费的因素进行分析,重点研究城镇化率和工业能源消费的非线性关系和相应的地区差异。结果表明:(1)长江经济带城镇化发展存在着明显的地区差异,上海、浙江等东部地区城镇化发展速度和水平明显优于云南、贵州等中西部地区。云南和贵州2012年的城镇化率远远低于2003年上海、浙江的城镇化率,显示出长江上游和下游之间存在着巨大的发展水平差距。(2)城镇化对工业能源消费存在显著的门槛效应,以城镇化率为门槛变量,存在两个结构变化点,分别为36.9%和48.3%。(3)在第一个门槛点前,城镇化对工业能源消费起抑制作用,前期城镇化的发展导致资源和人口的集聚效应明显,资源的利用效率和配置效率得到提升,从而抑制工业能源消费。在越过第二个门槛点后,城镇化对工业能源消费起正向作用,此时工业的发展和生活消费水准的提升对能源消费提出了更多的要求。最后为促进长江经济带城镇化和工业低碳化的协调发展,提出以下建议:加快长江经济带沿线各省份联动发展,缩小城镇化发展差异;针对城镇化率和工业能源消费的非线性关系,采取相应的措施引导和控制工业能源消费的变化趋势;协调城镇化进程和地区工业能源消耗,促进城镇化的健康发展。  相似文献   
62.
随着居民部门用能快速增长,各国都在致力于观察本国居民能源消费特征以减少碳排放,特别是发达国家。本文应用近30年的微观调查数据分析美国居民能源消费现状和趋势,为发展中国家提供一些借鉴意义。从总量上看,伴随着人口、家庭数量和建筑面积的上升,能源消费总量变化较小,趋于稳定;人均用能则呈下降趋势。从用能结构来看,以天然气和电力为主,2009年分别占比44%和41%;近30年来天然气占比小幅下降,电力占比上升明显;完善的天然气设施和电力服务体系使得能源可获得性高。从用途分类来看,取暖和家电占绝大比例,2009年分别占比41%和35%;取暖用能近30年来出现平缓下降趋势,燃料来源70%是天然气;家电设备用能占比明显上升,增长近1倍;制冷占比较小,近年出现小幅上升;热水用能则比较稳定。家庭炊事燃料以电力和天然气为主,2009年分别占比60%和34%。近30年,家用电器保有量和能源效率有显著提高。建筑用能方面,美国房屋服务时间长,后期建筑房屋在保温性能方面高于早期房屋,单位面积耗能下降。美国居民享受着较高水平的能源服务,能源消费总量在近30年没有明显变化,这和能源效率的提高有着密切关系;如完善的"能源之星"项目是一个强有力的措施,以及完善的能源统计制度为能源分析提供了有力的数据支撑。相比,中国存在居民炊事用能固体燃料占比较高、建筑服务周期短、建筑材料耗能比重大等问题。建议中国政府进一步完善能源统计制度、推行农村能源扶持项目和能源标识、加强建筑规划、落实建筑能耗标准。  相似文献   
63.
A chronic dietary risk assessment for pesticide residues was conducted for four age groups of the Argentinian population following the procedure recommended by the WHO. The National Theoretical Maximum Daily Intake (NTMDI) for 308 pesticides was calculated for the first time, using the Maximum Residue Limits (MRLs) from several Argentinean regulations and food consumption data from a comprehensive National Nutrition and Health Survey. The risk was estimated by comparing the TMDI with the Acceptable Daily Intakes (ADI) identified by various sources. Furthermore, for each of the compounds with a TMDI >65% of the ADI, a probabilistic analysis was conducted to quantify the probability of exceeding the ADI. In this study 27, 22, 10, and 6 active ingredients (a.i.) were estimated to exceed the 100% of the ADI for the different population groups: 6–23 month-old children, 2–5 year-old children, pregnant women, and 10–49 year-old women, respectively. Some of these ADI-exceeding compounds (carbofuran, diazinon, dichlorvos, dimethoate, oxydemeton-methyl and methyl bromide) were found in all four of these groups. Milk, apples, potatoes, and tomatoes were the foods that contributed most to the intake of these pesticides. The study is of primary importance for the improvement of risk assessment, regulations, and monitoring activities.  相似文献   
64.
针对我国生活垃圾的特点,提出了厨余等有机生活垃圾单独收集,在产生源头进行好氧堆肥处理。研制了好氧堆肥设备,由加热装置、通风装置、冷凝水收集和回灌装置,以及与该生物堆肥设备配套的生物过滤除臭装置、自控系统和数据采集软件几部分构成。自控系统由氧气、温度、湿度三路传感器以及2个控制器构成,并与加热装置、通风装置连接,能满足物料加热、供氧和散热的要求。本研究通过为期30 d的试运行实验表明,物料快速升温并稳定保持在高温阶段(50~60℃),物料中的氧气浓度保持在14%~16%范围内。在堆肥实验结束时,物料的含水率降至36.4%,有机质含量降至49%,另外,通过好氧速率指标也可判定物料达到腐熟。  相似文献   
65.
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   
66.
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   
67.
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   
68.
石灰岩山地造林树种——光皮树   总被引:17,自引:0,他引:17  
石灰岩山地的造林绿化,土壤条件差、难度大、任务重,选择好适生造林树种是获得成功的关键.光皮树适生特点突出、三大效益明显、营林技术可行,是石灰岩山地理想的造林树种,可在生产中推广应用.  相似文献   
69.
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   
70.
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   
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