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471.
淀粉及改性淀粉的阻垢性能测试   总被引:1,自引:0,他引:1  
实验利用浓硫酸氧化淀粉制备了改性淀粉,其颜色为棕红色;然后在不同浓度、温度、Ca2+浓度、pH下,对淀粉及改性淀粉的阻垢性能进行了测试.结果发现,淀粉高效阻垢的最佳浓度为8 mg/L,最佳温度为70℃,在此最佳浓度、最佳温度下对应阻垢效率为23.3%;改性淀粉高效阻垢的最佳浓度为0.61 mg/L,最佳温度为80℃,在...  相似文献   
472.
随着社会生活不断进步,旅游作为一种新的精神生活方式,使人们之间的交往不再局限于两点之间。人员的相互流动加强了彼此的了解,但也衍生出很多实际问题,环境保护也因此逐渐受到人们的重视,生态旅游的提出正是基于这样的现状。本文从生态旅游的角度来分析西部旅游与交通的关系,试图找出解决对策,真正实现落后地区的可持续发展。  相似文献   
473.
1株产电假单胞菌(Pseudomonas sp.)RE7的分离及特性研究   总被引:2,自引:0,他引:2  
微生物燃料电池(microbial fuel cell,MFC)阳极微生物的种类和作用机制对MFC的产电性能有着重要的影响.从已稳定运行1a的MFC的阳极室分离得到1株电化学活性革兰氏阴性细菌——菌株RE7,其16SrRNA基因序列与Pseudomonas aeruginosastrain CMG587有99%同源性,属于假单胞菌属(Pseudomonas sp.).利用菌株RE7构建的MFC的稳定产电和循环伏安曲线测定结果都表明,菌株RE7具有较强的电化学活性,利用菌株RE7构建的MFC的最大输出电压为352mV,相应的最大面积功率密度为69.2mW/m2,体积最大功率密度为6.2W/m3.由不同稀释比例的MFC排出液的产电效果比较可知,菌株RE7极有可能是通过自身分泌的氧化还原类物质进行电子传递.  相似文献   
474.
介绍了我国生物质资源利用现状及存在的主要问题,以某电厂利用生物质发电为例,从原燃料的用量、污染物排放情况及环境经济效益等方面进行分析,说明利用生物质发电是节能减排的重要途径。  相似文献   
475.
发达国家以气候变暖为契机,引领全球进入"后工业革命"时代,这个时代的特点就是,发展低碳经济,构建绿色体系。我国以节能减排为切入点,推进低碳经济的发展。文章论述了发展低碳经济面临的挑战与机遇,最后指出低碳经济是我国经济与环境融合的最佳选择。  相似文献   
476.
骆正山  刘璐  张新生  王小完 《灾害学》2022,(1):68-71+76
为保障能源储备安全,探究雷电和静电对储气库安全的影响。根据雷电和静电理论,构建储气库雷静电概率模型,分析雷静电对储气库的影响。考虑天然气扩散的特殊性,选取高斯烟羽模型预测气体扩散范围,并结合闪火后果准则对闪火危害范围进行分析,构建CCPS-BST模型对爆炸危害范围预测,分析风速及大气稳定度对三种危害后果的影响。结果表明,雷静电会增加储气库泄漏后发生闪火和爆炸的概率,气体扩散范围和闪火后果沿主导风向呈梭形分布,蒸气云爆炸后果由中心向四周扩散,三种危害范围都与风速和大气稳定度呈相反的变化。研究结果可为多因素下储气库安全分析研究提供参考,为降低灾害后果和维护储气库的日常安全提供了理论依据。  相似文献   
477.
20世纪80年代中期以来的气候变暖,尤其是90年代中期以来的气候显著变暖带给社会经济发展的利与弊,一直以来受到广泛关注。气候变暖对于建筑耗能,尤其是对采暖和降温总耗能的影响很值得研究。论文以主要使用电能进行空间调节的中国夏热冬冷地区为对象,以《夏热冬冷地区居住建筑节能设计标准JCJ134-2001》中所规定的采暖、降温耗电量限值为依据,研究了气候变暖对该区居住建筑单位面积采暖年耗电量、降温年耗电量及采暖降温年耗电总量的影响。结果表明,1986年以来的气候变暖,尤其是1996年以来的气候显著变暖,理论上使夏热冬冷地区居住建筑单位面积采暖年耗电量降低;同时增加了相当一部分地区居住建筑单位面积降温年耗电量;除个别地区外,气候变暖理论上使中国夏热冬冷地区居住建筑单位面积采暖降温耗电总量普遍下降。  相似文献   
478.
Based on the Green Development Indicator System issued by the Chinese government, this study conducted an in-depth evaluation of provincial green development in China, from 2013 to 2016. The findings of the study showed that: (1) significant regional differences existed across provinces in China regarding green development. (2) In terms of changing trends, the overall level of green development exhibited an upward trend during the years covered by our study, with a faster rising rate of development in eastern and central regions of China than in western ones. (3) In terms of spatial correlation, the spatial autocorrelation of China’s green development was evident. However, the spatial agglomeration of provincial green development gradually waned during the period in 2013–2016. (4) When it comes to drivers of spatial autocorrelation, the comparatively upward trend in the environmental field served as the main factor that drove green development from agglomeration to balance. (5) In terms of convergence, the tendency showed that less developed regions were about to catch up with leading regions in China in green development, especially as regards the dimensions of ecological protection and resource utilization.  相似文献   
479.
ABSTRACT

Natural history films use technological mediations to frame aspects of nature so as to communicate information, in part through engendering particular viewer affects. As an entertainment industry embedded in capitalist social relations and concerned with competition for finance and ratings, natural history film-making is also a search for “the money shot” – associated with extremes including rarity, sensational behavior, and otherwise un(fore)seen views. I highlight this sensationalizing impetus through ethnographic fieldwork conducted at the biannual UK Wildscreen film festival in 2010. Here, wildlife films were frequently presented as action dramas with a rhythm of anticipation, climax and satisfaction. I argue that, through stimulating significantly disconnective affects, such framing may work against composition of a caring ecocultural ethics that entwines human with more-than-human natures and futures; and that this tendency parallels the similarly disconnecting effects documented for pornographic film. In contrast, I engage with the differently constructive frames guiding the low budget, open access, activist film Green, which, perhaps paradoxically given the thrust of much of the natural history film industry, won the prestigious WWF Gold Panda Award at Wildscreen 2010. I follow framing theorist George Lakoff to emphasize that since cognition is both embodied and embedded in diverse inter-relationships, affective registers generating mimetic connection are as significant in communicating information regarding “the environment” as the text and words by which nature might be framed. I conclude that attention to affective registers and embodied (dis)connections in natural history film may enhance a turning of capitalist spectacle against itself, so as to work more effectively in service to the composition of abundant socionatural futures.  相似文献   
480.
ABSTRACT

The electricity grid is susceptible to numerous threats, especially severe weather events that have the potential to cause large-scale power outages. This has resulted in an increased emphasis on resilience against these events. Microgrids, small standalone power grids that have the ability to function independently from the greater electricity grid, have significant potential to improve response to environmental and anthropogenic crises. The vast majority of extant microgrids are generally small in scale, and operated under a conventional model of single operator, owner, and user. We argue that the ultimate potential of this approach will be in the development of multi-stakeholder microgrids which can combine a diversity of renewable and conventional power resources to respond to environmental hazards. The addition of stakeholders allows for increased diversification of generation sources, economies of scale, and other increased operational benefits and opportunities. However, there are significant challenges that arise with the additional layer of stakeholders in terms of governance, cost, and technical operations that can cause the multi-stakeholder model to be more difficult to implement. We develop the case for multi-stakeholder microgrids as a response to environmental hazards, and outline the challenges and questions facing the development of this form of microgrid.  相似文献   
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