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1.
The siting a landfill or waste treatment facility and the redevelopment of a brownfield or former landfill site are generally treated as independent issues in the research literature. Nonetheless, the two are important elements of community development and urban revitalization efforts. The purpose of this paper is to provide an integrated review of the current literature on attitudes toward waste treatment sites and their potential conversion for recreation use. We begin by examining research on residents’ perceptions of and attitudes toward proposed and existing waste treatment facility sites, including the perceived impacts and determinants of attitudes toward these sites. Next we summarize work that has explored the subsequent conversion of former landfills or brownfield sites, with a particular emphasis on repurposing these sites for green space and recreation use. We conclude by summarizing key issues and implications for future research and policy development. 相似文献
2.
指出了我国门窗的节能标准低下,多数门窗厂家整体技术水平低下,导致我国门窗的保温性能远低于西方发达国家,大量的能耗从门窗洞口等部位流失。分析了我国门窗节能的现状,阐述了国外节能门窗的应用状况,探讨了节能门窗的未来发展趋势。 相似文献
3.
选取了1995年至2007年我国29个省市面板数据,建立以城市化水平为被解释变量,能源消费和碳排放作为解释变量的模型,通过协方差分析检验和Haus man检验的分析结果,确定研究模型的形式为固定影响变截距模型,最后,通过对拟合模型的结果分析,实证结果表明:高能耗、高排放、粗放式经济发展方式不利于城市化水平的提高;同时,各省市的城市化发展水平也存在差异.因此,各省市应在城市化工业化进程中推进产业结构和能源消费结构调整使其朝着更有利于节能环保的方向演进,节能减排政策的调整重点应该放在能源强度和能源消费碳强度上. 相似文献
4.
低碳概念的逐渐深入人心,也使得低碳建筑开始出现在持续、高速发展的城市化进程中。在当下人们的环境保护意识逐渐增强以及对人居环境提出更高要求的背景下,低碳建筑不仅是环保理念在建筑实体上的物质载体体现,而且也是符合可持续发展理念的必然抉择。 相似文献
5.
LOU Can SI Bing-wen DENG Kai-dong MA Tao JIANG Cheng-gang TU Yan ZHANG Nai-feng JI Shou-kun CHEN Dan-dan DIAO Qi-yu 《农业科学学报》2015,14(12):2605-2617
This experiment was conducted to investigate the energy requirement of Dorper×thin-tailed Han crossbred ewes during non-pregnancy and lactation. Fifteen ewes after parturition were randomly assigned to three treatments: ad libitum(100%) feed intake and 80 or 60% ad libitum intake, and another nine non-pregnant ewes were assigned to a blank control group. Digestibility trials were performed in the non-pregnant ewes and in the lactating ewes on the 20 th, 50 th, and 80 th d of lactation. In parallel with the digestibility trial, a respirometry experiment was conducted to determine the methane and carbon dioxide production with an open-circuit respirometry system that was equipped with respiratory chambers. The net energy(NE) and metabolizable energy(ME) requirements for maintenance and growth were calculated using the carbon and nitrogen balance method. The results revealed that the carbon(C) and nitrogen(N) excretions and energy losses at faeces and urine, as well as the output of methane and CO2, increased significantly with decreasing feed intake(P0.01). The apparent digestibilities of C in th e stages of non-pregnancy and early, middle and late lactation were 55.8–58.3%, 62.5–73.8%, 64.8–71.3%, and 61.7–65.0%, respectively, and the apparent digestibilities of N were 45.2–51.3%, 73.7–82.7%, 72.8–80.5%, and 73.6–76.5%, respectively. The corresponding energy apparent digestibilities were 52.0–56.3%, 60.7–76.6%, 61.0–68.8%, and 61.4–67.7%, respectively. The ME/DE(digestible energy) values were 79.5–85.9%, 79.4–83.5%, 81.0%–85.3% and 78.6–82.9%, respectively. The maintenance requirements of NE, ME, and the efficiencies of ME utilisation for maintenance during the stages of non-pregnancy and early, middle and late lactation were 215.5, 253.1, 247.7, and 244.7 k J kg~(–1) BW0.75 d, and 372.4, 327.1, 320.9, and 362.0 k J kg~(–1) BW0.75 d, and 0.58, 0.77, 0.77, and 0.68, respectively. The ME requirement for the growth of non-pregnant ewes was 31.3 MJ kg~(–1) BW gain. 相似文献
6.
Assessment of the preference of sheep for fresh, dried or ensiled forms of mucuna (Mucuna pruriens var utilis) forage was followed by investigations into the effect of supplementing straw-based diets with the forage. Four sheep were offered fresh, dried and ensiled forms of the forage in a cafeteria style to assess their preference. In the second experiment, 20 sheep were randomly assigned to four dietary treatments, namely, alkali-treated straw only (M0), treated straw supplemented with mucuna forage at 0.3% (M10), 0.6% (M20) or 0.75% (M25) of body weight (approximately 10%, 20% and 25%, respectively, of the total dry matter intake). The daily feed intakes were determined and the sheep were weighed weekly for 10 weeks. The sheep showed a marked preference for fresh mucuna forage over either the dried or ensiled forms. The total dry matter intake increased by 15% and 21%, respectively, with M20 and M25. All the groups lost weight over the feeding period. However, only M0 gave weight losses during the second half of the feeding period. The feed conversion efficiency followed a trend similar to that for weight gains. M20 had the greatest effect on growth and feed conversion efficiency. 相似文献
7.
LIYan-fei WANGZhe NIUShu-ling 《东北农业大学学报(英文版)》2004,11(2):160-162
24 healthy periparturient cows were randomly allocated into three groups and fed 100% energy diet(NRO standard diets), 120% energy diet and 80% energy diet, respectively, beginning at 28 days prior to anticipated parturition. After parturition, all the cows were provided with the lactation ration ad libitum until the day 56 postpartum.The objectives of the study were to investigate the effect of energy intake during the dry period on the production performance in the postpartum cows. The results indicated that the cows fed with high energy diet during the dry period had a lower dry material intake (DMI) and reduced milk production and a significant body weight (BW) loss compared with the cows fed with 80% energy diet and 100% energy diet. The results suggested that energy intake during the dryperiod was an important factor that influences and regulates DMI, milk production and energy equilibration of postparturient cows. 相似文献
8.
9.
针对北方冬季密闭畜禽舍普遍存在的舍内湿度大、传统除湿方法成本高的问题,设计了一种以翅片管换热器为核心部件的自然冷凝式节能除湿系统,利用北方冬季寒冷的舍外自然条件使制冷剂充分制冷后循环引入翅片管换热器中,依据冷凝原理实现舍内高湿气体冷凝析湿。该除湿系统实现舍内空气内循环除湿,减少直接或间接通风除湿造成大量的热量损失。利用湿空气理论计算除湿速率,通过在密闭试验舱进行试验测试来验证换热除湿系统的工作性能。结果表明,翅片管换热器有效换热面积、舱内空气和制冷剂初始温差、风机风速和制冷液流量对除湿速率和舱内降温有着正向影响。风速为1m/s、平均初始温差约为33℃情况下,在约为36m3的试验舱内平均降温为4.67℃,平均除湿速率约为2.69kg/h。在有效换热面积为18m2的换热器除湿试验中,空气与制冷剂的质量流率比为0.31、0.63和0.95时,能效比分别为5.63、12.25和11.03,表明换热器存在热交换能力的上限,能效比不能随风机风速增大而持续增加,可为除湿系统的节能调控提供参考。该系统充分利用了东北寒区冬季舍外自然低温,除湿和节能效果明显,可为解决北方冬季畜禽舍除湿和节能之间矛盾提供有效途径。 相似文献
10.
基于PLSR的土壤颜色预测方法及其与色系转换法的对比研究 总被引:1,自引:1,他引:1
传统的土壤颜色测定主要采用蒙塞尔比色卡比对,精度高,但费时费力。近年来尝试采用色系转换法预测土壤颜色,方法较为简便。基于土壤高光谱反射率和偏最小二乘回归(PLSR)方法进行土壤颜色预测,并与色系转换法进行对比研究。采集皖赣鄂交界地区76个不同颜色的土壤样品,分别采用PLSR及色系转换法进行土壤颜色预测,并与实测结果进行了对比。结果表明,PLSR交叉验证的R2cv分别达到0.62、0.61和0.75,测定值标准偏差与标准预测误差的比值(RPD)分别达到1.94、1.67和2.15,说明PLSR模型用于土壤颜色预测是可行的;其均方根误差(RMSE)仅为1.32、0.55和0.97个单位,较色系转换法的RMSE分别低0.94、1.24和0.95个单位,其HV/C整体预测误差?E的平均值为1.91,较色系转换法的平均值低5.16,说明PLSR方法预测土壤蒙塞尔颜色较色系转换法更优。该方法为土壤颜色的获取提供了一种新的途径。 相似文献