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521.
锂电池以其优异的性能得到了广泛的应用,其废弃量也在逐步增加.如果不对其进行有效的处理回收,不仅给环境保护带来巨大的压力,而且也会造成钴、锂、镍和锰等有价金属的极大浪费.综述了国内外对废旧锂电池回收技术的研究现状,比较了不同回收途径的优缺点,讨论了回收技术的发展方向,着重介绍了共沉淀法在废旧锂电池有价金属回收中的应用.此外,随着锂离子电池生产技术的发展,新的电极材料将会出现并取代过渡金属氧化物,同时也需要相应的电解液与之匹配,这将向废旧锂电池回收技术提出了新的要求.  相似文献   
522.
张超  陈银广  顾国维 《环境科学》2013,34(4):1479-1484
同时回收氮磷可以显著提高碱性发酵污泥的脱水性能,但是目前对其机制尚不清楚.通过批式试验,研究了ζ电位、二价离子、胞外聚合物、溶解性聚合物以及鸟粪石对碱性发酵污泥脱水性能的影响.结果表明,在最佳回收条件下(pH=10.0,n(P)/n(N)=1.3 mol.mol-1,n(Mg)/n(N)=1.9 mol.mol-1),镁离子不仅能使|ζ|电位减小到14 mV以下,而且使一价阳离子与二价阳离子比例降低到9 mol.mol-1以下;同时回收氮磷可以显著降低溶解性多聚物和胞外聚合物的含量,尤其是溶解性蛋白质和松散型胞外聚合物的含量;这些变化都促进了碱性发酵污泥的脱水.此外,鸟粪石的形成也有助于提高脱水效果.  相似文献   
523.

Introduction

Research in human error has provided useful tools for designing procedures, training, and intelligent interfaces that trap errors at an early stage. However, this “error prevention” policy may not be entirely successful because human errors will inevitably occur. This requires that the error management process (e.g., detection, diagnosis and correction) must also be supported. Research has focused almost exclusively on error detection; little is known about error recovery, especially in the context of safety critical systems. The aim of this paper is to develop a research framework that integrates error recovery strategies employed by experienced practitioners in handling their own errors.

Method and Results

A control theoretic model of human performance was used to integrate error recovery strategies assembled from reviews of the literature, analyses of near misses from aviation and command & control domains, and observations of abnormal situations training at air traffic control facilities. The method of system dynamics has been used to analyze and compare error recovery strategies in terms of patterns of interaction, system affordances, and types of recovery plans. System dynamics offer a promising basis for studying the nature of error recovery management in the context of team interactions and system characteristics.

Impact on industry

The proposed taxonomy of error recovery strategies can help human factors and safety experts to develop resilient system designs and training solutions for managing human errors in unforeseen situations; it may also help incident investigators to explore why people's actions and assessments were not corrected at the time.  相似文献   
524.
In this paper, we show that the potential for endogenous technological change in alternative energy sources may alter the behaviour of resource-owning firms. When technological progress in an alternative energy source can occur through learning-by-doing, resource owners face competing incentives to extract rents from the resource and to prevent expansion of the new technology. We show that in such a context, it is not necessarily the case that scarcity-driven higher traditional energy prices over time will induce alternative energy supply as resources are exhausted. Rather, we show that as we increase the learning potential in the substitute technology, lower equilibrium energy prices prevail and there may be increased resource extraction and greenhouse gas emissions. We show that the effectiveness and the incidence of emissions reduction policies may be altered by increased potential for technological change. Our results suggest that treating finite resource rents as endogenous consequences of both technological progress and policy changes will be important for the accurate assessment of climate change policy.  相似文献   
525.
Burton C  Mitchell JT  Cutter SL 《Disasters》2011,35(3):488-509
Hurricane Katrina of August 2005 had extensive consequences for the state of Mississippi in the United States. Widespread infrastructure and property damage, massive social dislocation, and ecological loss remain among the many challenges faced by communities as they work towards 'normalcy'. This study employs repeat photography to understand differential recovery from Hurricane Katrina in Mississippi. Revealing change with conventional landscape photography, a process known as repeat photography, is common in the natural sciences. Simply stated, repeat photography is the practice of re-photographing the same scene as it appears in an earlier photograph. Photographs were taken at 131 sites every six months over a three-year period. Each photograph was assigned a recovery score and a spatially interpolated recovery surface was generated for each time period. The mapped and graphed results show disparities in the progression of recovery: some communities quickly entered the rebuilding process whereas others have lagged far behind.  相似文献   
526.
This paper analyses structural and personal exposure to Hurricane Katrina. Structural exposure is measured by flood height and building damage; personal exposure is measured by the locations of 911 calls made during the response. Using these variables, this paper characterises the geography of exposure and also demonstrates the utility of a robust analytical approach in understanding health‐related challenges to disadvantaged populations during recovery. Analysis is conducted using a contemporary statistical approach, a multiple additive regression tree (MART), which displays considerable improvement over traditional regression analysis. By using MART, the percentage of improvement in R‐squares over standard multiple linear regression ranges from about 62 to more than 100 per cent. The most revealing finding is the modelled verification that African Americans experienced disproportionate exposure in both structural and personal contexts. Given the impact of exposure to health outcomes, this finding has implications for understanding the long‐term health challenges facing this population.  相似文献   
527.
Evidence of inbreeding depression is commonly detected from the fitness traits of animals, yet its effects on population growth rates of endangered species are rarely assessed. We examined whether inbreeding depression was affecting Sierra Nevada bighorn sheep (Ovis canadensis sierrae), a subspecies listed as endangered under the U.S. Endangered Species Act. Our objectives were to characterize genetic variation in this subspecies; test whether inbreeding depression affects bighorn sheep vital rates (adult survival and female fecundity); evaluate whether inbreeding depression may limit subspecies recovery; and examine the potential for genetic management to increase population growth rates. Genetic variation in 4 populations of Sierra Nevada bighorn sheep was among the lowest reported for any wild bighorn sheep population, and our results suggest that inbreeding depression has reduced adult female fecundity. Despite this population sizes and growth rates predicted from matrix-based projection models demonstrated that inbreeding depression would not substantially inhibit the recovery of Sierra Nevada bighorn sheep populations in the next approximately 8 bighorn sheep generations (48 years). Furthermore, simulations of genetic rescue within the subspecies did not suggest that such activities would appreciably increase population sizes or growth rates during the period we modeled (10 bighorn sheep generations, 60 years). Only simulations that augmented the Mono Basin population with genetic variation from other subspecies, which is not currently a management option, predicted significant increases in population size. Although we recommend that recovery activities should minimize future losses of genetic variation, genetic effects within these endangered populations-either negative (inbreeding depression) or positive (within subspecies genetic rescue)-appear unlikely to dramatically compromise or stimulate short-term conservation efforts. The distinction between detecting the effects of inbreeding depression on a component vital rate (e.g., fecundity) and the effects of inbreeding depression on population growth underscores the importance of quantifying inbreeding costs relative to population dynamics to effectively manage endangered populations.  相似文献   
528.
简介了软包装印刷工业复合生产过程中产生的VOCs污染物,探讨了现有ACF咐附回收有机溶剂设备存在的技术问题;结合软包装复合生产工艺特点,提出一种闭式循环的改良工艺,以解决能量浪费问题。  相似文献   
529.
Urine diversion (UD) has great potential to contribute to sustainably managing wastewater by separating urine at the source and recovering nutrients for reuse in agriculture. While factors enabling the UD technology in Sweden are thought to involve policies supporting nutrient recovery/reuse, on closer inspection, the variable success of UD systems has revealed that critical factors for success also relate to human-centred issues of social organisation, participation and incorporation of social knowledges of a variety of stakeholders into the decision-making process in which new technologies are trialled and adopted. Through the analytical lens of strategic niche management, we consider how early experimentation in UD has involved user participation and whether internal processes of learning, networking and visioning have been consciously considered and to what effect. As niche experiments are enabled/disabled not only by informal institutions such as values and social norms but also formal regulatory institutions, we have concurrently analysed the broader environment in which policies and institutions influence, to varying degrees, the uptake of UD.  相似文献   
530.
ABSTRACT

Community gardens are often considered to be therapeutic landscapes capable of supporting wellbeing and recovery particularly for members of vulnerable or disadvantaged groups such as refugees. This is regularly identified as resulting from the capacity for communal garden activities to enable realisation of self-efficacy, the formation of social connections and the assumed benefits of “being” in nature. These approaches tend to privilege anthropocentric perspectives that perpetuate conceptions of a human/nature binary. As such, existing literature has paid little attention to the role in refugee recovery of the visceral, affective force of matter encountered in the embodied act of gardening. By adopting such an approach, this paper aims to tease out the particularities of how bodies in these places engage with the ecological experiences of their new homes. Such encounters are never simply harmonious. They can reinforce dislocation while concurrently providing sites where gardeners are able to strengthen their adaptive capabilities via experimentation. To understand the utility of community gardening to support refugee recovery we argue it is necessary to not only attend to human participants and issues of design, infrastructure, and garden management, but also to the impact of particular forms of human and more-than-human entanglements that emerge in these spaces. In so doing we suggest that the notion of community and belonging in these settings should be broadened to more deeply engage with the more-than-human. To explore this, we focus on a small-scale, in-depth case study of a food-producing garden established for Burmese refugees in Canberra, Australia.  相似文献   
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