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991.
绿色消费是解决当前中国环境污染的重要战略组成部分,本文研究了对上海市开展的关于绿色消费1200余份调查问卷。研究结果显示:1)人们环境意识和绿色消费意愿普遍提高,98%的受访者愿意为保护环境做出自身行为的改变。2)绿色消费认知参差不齐。对绿色产品的认知渠道不多,绿色产品的标签知晓率低于30%。3)绿色消费意愿强烈但支付能力还有限,82%的消费者愿意购买绿色产品,但支付不能超过同类普通商品10%的额外费用。研究结果还表明:绿色消费与性别、年龄、职业以及学历等具有相关关系。 相似文献
992.
从人口的家庭结构、年龄结构、城乡结构变化的角度对城镇建筑能耗的变化进行了分析.根据测算,2010~2030年,中国20~39岁的人口从4.46亿下降到3.28亿,减少约1.18亿;2030年全国的平均家庭规模从3.10人下降到2.48人,全国家庭数量将突破5.5亿户;按照现有模式发展,2030年城市化率达到64.2%.人口结构变化的影响下,2020年的城镇建筑需求总面积为3.14′1010m2,人均住宅面积为37m2,建筑能耗达到1.72′109tce;2030年的建筑需求总面积为3.84′1010m2,人均住宅面积为42m2,能耗为2.13′109tce. 从需求角度看,未来建筑规模的增长速度将逐步放缓.如果不能及时调整发展战略,未来会出现较大规模的住宅空置和资源浪费. 相似文献
993.
994.
对北京市5座生活垃圾堆肥设施(南宫、顺义、阿苏卫、燕山、沃绿洁)开展耗能、排污研究,实地调查获取5座设施2009—2011年的耗能、排污指标数据,并分析垃圾发酵、恶臭控制、渗滤液处理3个工艺的耗能排污特征,总结各工艺及设施层次耗能排污的影响因素. 结果表明:5座设施发酵工艺年耗水量(y,103t)与年垃圾处理量(x,103t)呈线性关系,有y=0.0551x+3.0627;隧道堆肥发酵工艺的单位(t)垃圾耗电、渗滤液及残渣产量均低于间歇式动态堆肥;隧道堆肥恶臭控制工艺耗水量占厂区总耗水量的5.92%,用电量占厂区总耗电量的23.78%;渗滤液处理工艺的耗电量与ρ(CODCr)呈正相关(P<0.05,R=0.981),但与渗滤液处理量相关性不强. 垃圾组成及性质、工艺差别、污染物特性影响工艺耗电量及恶臭、渗滤液产生量. 完善堆肥设施各个工艺环节并进行中水回用,有利于削减设施耗能排污. 相似文献
995.
996.
Effects of mussel dredging on sediment metabolism (oxygen uptake and sulfate reduction rates) and phosphorus dynamics (flux across sediment-water interface and sequential extraction) were examined in Limfjorden (Denmark) during spring (May) and summer (August). Sediment samples were taken during mussel dredging and in addition an experimental simulation of the dredging was performed to investigate short-term changes in phosphorus (P) dynamics. Iron-bound P was reduced by up to 2/3 in the surface layer in the dredging track (from 31 to 8?mmol?P?m?2), whereas the dissolved P-pools and less reactive particulate pools were not affected by dredging. Sediment oxygen consumption was enhanced immediately after dredging, but returned to the initial level after 4 days (20–40?mmol?m?2?d?1). The enhanced consumption was attributed to reoxidation of reduced compounds released during dredging. Sulfate reduction rates were high in the area (13–15?mmol?m?2?d?1) and sulfides competed with P for oxidized iron resulting in low iron-bound pools in the area (<4% of total P pools). Sulfate reduction rates were stimulated by the resuspension of sediments, especially in August, where a subsurface maximum was found, possibly due to a mixing of labile organic matter into these layers. In contrast sulfate reduction rates were reduced in the dredging track due to removal of labile organic matter from the surface layers. The loss of P during dredging was to some extent counteracted by regeneration of iron-bound P pools in the surface layers. The release of P due to mussel dredging was estimated to be in the same order of magnitude as the annual loading from the catchments and point sources to Limfjorden. 相似文献
997.
Solar energy feeds all life on this planet's surface. The energy of the Sun can be tapped and converted to the different forms of energy by renewable energy systems, such as solar power plants, photovoltaic systems, and plants. Land is needed for food production, which is the most globally important activity. With increasing population, the required area is determined by consumption and production patterns. The world is globally divided into poor and rich areas of production and consumption, which have large differences. Iran's energy and food production and consumption are studied and compare with poor and rich examples. It is concluded that available agricultural land is limited and currently declining per capita due to population growth. The expansion of irrigated crop area, high-quality seed, and modern farming techniques can marginally improve agricultural productivity and provide relative self-sufficiency in grain production. Much of the growth in Iran's renewable energy is attributed to hydroelectricity power plants. Solar energy, wind, hydro and geothermal energy are also potential forms of sustainable energy in Iran. 相似文献
998.
基于1978-2012年国内外能源价格、产业发展以及我国能源消耗的相关数据,通过构建一般调节作用模型和状态空间模型比较了国内外能源价格对我国能源消耗的作用路径以及静态和动态作用效力,结果表明:仅考虑单一路径时,国内外能源价格均难以对我国能源消耗起到有效的调节作用,但综合考虑多种路径时则表现出较强的影响。能源价格的提高通过影响产出总量和产业结构产生了较强的能耗拉动效应,但却通过影响能源效率产生了一定的能耗抑制效应。此外,国内外能源价格的联动性低,价格传导受阻。样本区间内,国内能源价格对我国能源消耗的影响显著大于国外能源价格的作用;后者通过价格路径对我国能源消耗的作用短期内并不显著,长期则表现出了一定的抑制性。总体来看,国内外能源价格关联性越强(价差越小),能源价格提升对于能耗总量的抑制作用越明显;我国能源价格的合理上升有利于节能降耗。 相似文献
999.
The most important question raised from issues of environmental degradation is how economic activities bring about changes that will result in pollution. In the pursuit of tourism economy, contrary to popular interest, the travel and tourism (T&T) industry may cause environmental damages through the emissions of carbon dioxide (CO2) from energy consumption in areas such as transportation and delivery of amenities. Given this major concern, this paper attempts to investigate the linkage between tourism and CO2 emissions in Malaysia between 1981 and 2011. In particular, this study fills the knowledge gap by taking a closer look at the impact of international tourist arrivals on CO2 emissions by sector – electricity and heat generation and transport. Results from the bound test method suggest that there exists a long-run relationship among the variables under consideration when CO2 emissions become the dependent variable. The original result is similarly robust to alternatives, which are CO2 emissions from sectors of electricity and heat generation and transport. Furthermore, the vector error correction model causality analysis indicates a causal relationship between tourism and CO2 emissions by transport and electricity and heat generation. Subsequently, several tourism-related policies are drawn from these findings. 相似文献
1000.
碘化汞和碘化钾的碱性溶液与氨反应能生成淡红色胶态化合物,该颜色在较宽的波长内具有强烈吸收。国家标准纳氏试剂光度法是常见的测定氨氮的方法,该法操作简便,灵敏度高,但预处理过程繁琐。通过对校准曲线的绘制条件进行改进,并对水样的预处理方法作了进一步的探讨,改进后的方法操作简便,对水样进行测定,与标准法相对照,结果基本一致。 相似文献