废旧电脑的处置现状与绿色电脑概念的普及

慨述了发达国家在废电脑处理方面的现状，并对绿色电脑进行了分析与展望。     

Determinants of the marginal willingness to pay for improved domestic water and irrigation in partially electrified Rwandan villages

Access to water for domestic and irrigation uses remains limited across Sub-Saharan Africa, particularly in rural areas. While the technical feasibility of implementing innovative technologies to improve water supply has been often evaluated, less is known about the drivers that motivate users to pay for obtaining the inherent benefits of improved water supply. In this article, the determinants of the marginal willingness to pay (mWTP) for improved domestic and irrigation water are investigated. For this purpose, a contingent valuation study is performed in rural Rwanda. This study uses survey data from 316 households situated in 8 villages, in which ~20% of the households receive electricity thanks to microgrids powered by solar energy. It is found that the mWTP for improved domestic water supply is influenced by the proportion of children in the household, business ownership, and satisfaction with water quantity and quality. The mWTP for irrigation is determined by respondent education, business ownership and crop area planted. This paper contributes to the literature by allowing a comparison of the determinants of the mWTP for improved domestic water supply to the determinants of the mWTP for irrigation. Another contribution is to examine the mWTP for improved water infrastructure in partially electrified villages. Identifying areas with high marginal benefits from water can guide infrastructure investment and electrification efforts while improving well-being and increasing revenues in rural areas.     

Dual function of allopreening in the cooperatively breeding green woodhoopoe, Phoeniculus purpureus

Allopreening is a widespread but little-studied phenomenon in birds and is particularly prevalent in species where individuals are forced into close proximity. Such a situation facilitates the transfer of ectoparasites between individuals and allopreening has therefore been proposed to serve a hygienic function. In addition, allopreening might theoretically play a role in social communication. Green woodhoopoes (Phoeniculus purpureus) are cooperatively breeding birds that roost communally every night in a tree cavity and are thus susceptible to high ectoparasite loads. Our results suggest that allopreening of the head and neck (“head”), which cannot be efficiently self-preened, serves a primarily hygienic function: all individuals, irrespective of sex, dominance status, and group size, donated and received similar rates of head allopreening and terminated a similar proportion of bouts in which they were involved. Furthermore, there was a high occurrence of reciprocation and head allopreening occurred at a constant rate throughout the year. In contrast, allopreening of the rest of the body, which is accessible to the recipient itself, is likely to serve a primarily social function: body allopreening rates were higher in larger groups; dominant individuals received more body allopreening and terminated a significantly higher proportion of bouts than subordinates; and subordinates donated body allopreening at a higher rate than dominants. Moreover, bouts initiated by dominants were more likely to be reciprocated than those initiated by subordinates and body allopreening rates varied seasonally. Allopreening in the green woodhoopoe is therefore likely to serve a dual function, depending on the part of the body involved.     

Does cadence of Iguana iguana displays facilitate individual recognition?

Iguanid lizards communicate threat, courtship and territorial advertisement through stereotyped headbob displays. It has been hypothesized that slight interindividual differences in these displays might enhance individual recognition and maintain dominance relationships within populations, but the precise display elements responsible have not been determined. The purpose of this study was to examine if experimentally induced differences in displays would decrease recognition of individual conspecifics. Specifically, social interactions between adult male green iguanas (Iguana iguana) were examined at normothermic and hypothermic body temperatures. Whereas the cadence (rate of muscle contraction) of stereotypic displays of individual lizards was slowed at hypothermic body temperature (Q ₁₀ 1.6), the amplitude (maximal muscle contraction) of hypothermic displays remained constant relative to normothermic displays. Normothermic lizards viewing a display from a hypothermic lizard responded to that display as if it were performed at a normothermic cadence. During paired encounters between lizards (one hypothermic, one normothermic), dominant/subordinate dyads within the group were unusually maintained regardless of which individual was hypothermic. The exception occurred when dominant individuals at the lowest experimental body temperatures retreated from subordinate individuals. The results suggest that individual lizards recognized their relative social status even when cadence of displays was radically altered, indicating that cadence alone probably does not function in individual recognition. Other morphological, display elements, or scent cues may provide information useful in individual recognition.Communicated by G.M. Klump     

MFC处理人工湿地生物堵塞物及同步产电研究

为探究MFC（microbial fuel cells,微生物燃料电池）对人工湿地（constructed wetland,CW）堵塞物EPS（extracellular polymeric substances,胞外聚合物）组分的处理效果和产电性能,构建双室MFC,设置闭路组（closed circuit MFC,MFC-C）和开路组（open circuit MFC,MFC-O）对EPS中的主要组分〔PN（protein,蛋白质）和PS（polysaccharide,多糖）〕及人工湿地堵塞物进行处理,分析底物类型、底物浓度和外阻（R_ex）对MFC系统产电性能的影响及系统对底物的处理效果.结果表明:①MFC系统的产电性能受底物类型、底物浓度及R_ex的影响较大,底物浓度增加1.5倍（由200 mg/L增至500 mg/L）时,MFC系统最大电压（V_max）增加5.8%（PN）,最大功率密度（P_max）分别增加188.30%（PN）和124.21%（PS）;保持底物类型和底物浓度不变,R_ex增加9倍（由100 Ω增至1 000 Ω）时,MFC的V_max分别增加110.26%（PN）和92.81%（PS）,P_max分别增加109.19%（PN）和7.51%（PS）.②PN可全部被阳极微生物利用,但同时阳极微生物会分泌PS,底物浓度增加1.5倍时,出水中ρ（PS）分别增加107.85%（MFC-C）和78.55%（MFC-O）;R_ex增加9倍时,ρ（PS）分别增加415.85%（MFC-C）和294.29%（MFC-O）;底物为PN时,出水中ρ（PS）均表现为MFC-C < MFC-O,说明MFC形成的微弱电场在一定程度上可抑制PS的分泌.③人工湿地堵塞物可作为MFC的底物,随着投加量的增加（除堵塞物投加量为0.500 g/L外）,V_max（约750 mV）变化不大,但电压稳定时间随投加量的增加而略有延长;堵塞物投加量为6.667 g/L时,MFC的P_max为12.25 mW/m2,内阻（R_int）为1 112.5 Ω,MFC产电性能下降.研究显示,人工湿地堵塞物EPS可以作为MFC的阳极底物并同步实现能源回收.      

箱式变电站中的电气安全与防护

分析我国农网改造中箱式变电站发展的新趋势,针对一些变电站运行的安全问题,笔者提出以箱变的外形结构、内部构造、独立模块为主的八防功能———防火、防凝露和凝霜、防水、防高温、防低温、防潮、防腐蚀、防小动物进入以及新的防雷与接地的设计方案;阐述改进箱变安全的实施方法,并在ZXW1-35(10)系列智能型无人值守箱式变电站中应用。使用证明,对比国家电气安全标准,该箱式变电站在偏僻之处,特别是在多雷地区,箱式变电站中的一次、二次及通讯设备不会被破坏并将损坏降到最低限度,能够保证电网的正常运行,同时符合国家电气设备安全质量标准。随着新科技成果的推广和应用,箱变的安全性和电网运行的质量得到进一步提高。     

人类活动与气候变暖互助响应研究

本文从“温室效应”的实质,温室气体的“变暖潜能”入手,分析了人类活动与气候变暧互助响应的“蝶形效应”,提出了人类共同控制金球变暖的行动方略。     

Optimal design for water conservation and energy savings using green roofs in a green building under mixed uncertainties

Most water conservation and energy saving strategies for residential homes and commercial buildings have higher initial capital investment than traditional ones. Yet, the added benefits of these “green” building strategies should outweigh the increase of initial capital cost at the end of the house lifetime. Using green roof systems to cool houses gives rise to uncertainties from local precipitation patterns and the unstable market related costs and benefits. The optimal area of green roof to balance cost, benefit, and risk remains unknown. To achieve such a complex systems analysis, a grey stochastic programming model was prepared to address the optimal design strategies under mixed uncertainties. Such a cost-benefit-risk trade-off model was formulated for this study through an optimization framework to retrieve the optimal design strategies with respect to a typical Florida residential home (shingle and metal roofs). It is particularly designed to synergistically integrate a green roof with beneficial reuse of gray water and stormwater while achieving some degree of energy savings. The study identifies the optimal green roof area that keeps within the cost of a conventional home over a specific life time, such as 50 years. Research findings show that as the reliability level associated with the chance constraint was decreased, the upper bound of the green roof area did not vary much for either shingle or metal roofs. The lower bound was found to decrease in the same situation, however, due to the higher minimum cost of the cistern in relation to the greater volume of expected rainfall, forcing the required green roof area to decrease.     

Selecting safer building products in practice

In recent years the green building movement has focused increased attention on chemical hazards in building products and the need to select safer alternatives. This paper describes a number of tools available to architects and other building professionals and explores the product evaluation process behind one resource, BuildingGreen’s GreenSpec directory, as a window into the imperfect reality of alternatives assessment in the building design field.     

黄姜废水微生物燃料电池产电去污性能研究

以H型反应器研究了微生物燃料电池(MFC)利用黄姜废水产电的效果,并结合产电周期中阳极液氧化峰电位、COD、pH值等物化指标及进出水IR、GC-MS谱图变化讨论了MFC对黄姜废水污染物的去除特性.黄姜废水MFC内阻约480 Ω,最大功率密度可达1 18.1 mW/m2,外接1 000 Ω电阻时,5 mL黄姜废水所含有机...