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571.
This study focuses on the electrodeposition of Ni and Ni–Fe alloys from synthetic solutions similar to those obtained by the dissolution of electron gun (an electrical component of cathode ray tubes) waste. The influence of various parameters (pH, electrolyte composition, Ni2+/Fe2+ ratio, current density) on the electrodeposition process was investigated. Scanning electron microscopy (SEM) and X-ray fluorescence analysis (XRFA) were used to provide information about the obtained deposits’ thickness, morphology, and elemental composition. By controlling the experimental parameters, the composition of the Ni–Fe alloys can be tailored towards specific applications. Complementarily, the differences in the nucleation mechanisms for Ni, Fe and Ni–Fe deposition from sulfate solutions have been evaluated and discussed using cyclic voltammetry and potential step chronoamperometry. The obtained results suggest a progressive nucleation mechanism for Ni, while for Fe and Ni–Fe, the obtained data points are best fitted to an instantaneous nucleation model.  相似文献   
572.
The thermal LDPE degradation mechanism harnessing a high-pressure autoclave surrounded by a furnace was investigated in this work. Rates of formation of gas, liquid, and solid during degradation of PE plastic wastes in cyclohexane as solvent at 400 and 425°C have been experimentally determined. Four reaction mechanisms have been proposed and tested to estimates of gas, liquid, and solid. Proposed mechanisms are based on the assumption that the reactions are pseudo-first-order with respect to the reacting species. Pseudo-first-order rate constants for each of the indicated mechanistic steps have been calculated by nonlinear regression analysis. The best fit was obtained by model 2 (pure parallel reaction mechanism), and its activation energy was determined.  相似文献   
573.
Photo identification is an important tool for estimating abundance and monitoring population trends over time. However, manually matching photographs to known individuals is time-consuming. Motivated by recent developments in image recognition, we hosted a data science challenge on the crowdsourcing platform Kaggle to automate the identification of endangered North Atlantic right whales (Eubalaena glacialis). The winning solution automatically identified individual whales with 87% accuracy with a series of convolutional neural networks to identify the region of interest on an image, rotate, crop, and create standardized photographs of uniform size and orientation and then identify the correct individual whale from these passport-like photographs. Recent advances in deep learning coupled with this fully automated workflow have yielded impressive results and have the potential to revolutionize traditional methods for the collection of data on the abundance and distribution of wild populations. Presenting these results to a broad audience should further bridge the gap between the data science and conservation science communities.  相似文献   
574.
ABSTRACT

Previous research has suggested that corporatist polities tend to enact more ambitious environmental policies than others. Here it is argued that the macro concept of corporatism can be dissected into three components: inclusiveness, consensualism and strength of tripartite organisations. These components of corporatism can be measured at the meso-level of policy networks. It is proposed that inclusiveness and consensualism are related to ambitious climate policy but exclusive tripartite coalitions can be detrimental for the ambitiousness of climate policy. This argument is backed by evidence from policy network surveys in two similar corporatist countries where climate change policies diverge: Sweden, where policies are ambitious, and Finland, where they are less so. It is found that in Sweden the climate change policy network is more consensual and slightly more inclusive, while in Finland tripartite organisations play a strong role.  相似文献   
575.
In this paper, we examine the claims that competing networks make over the safety or risk attached to an energy-from-waste (EfW) plant in Crymlyn Burrows in South Wales. The paper draws upon a governmentality perspective and identifies three networks at the heart of decision-making: a dissenter network, a developer network and a regulatory network. The arguments put forward by the networks reveal much about how power relations are realised at a local level. The paper draws upon a longitudinal case study approach to demonstrate that networks have a life beyond a development decision and that key actors can align themselves with competing networks at different points in the development and operation phase of an EfW plant.  相似文献   
576.
在北京市经济发展的新时期.循环经济理念和发展模式的引入进一步提升了北京经济增长的质量.促进北京经济向着“低投入、高产出、可循环”的方向发展。在压缩的工业化和工业制造业耗能过大的双重压力下,北京应积极探索工业循环经济的发展模式。立足予北京工业循环经济的发展现实,提出企业清洁生产模式、生态工业固模式和工业废弃物可持续利用模式.通过对北京市第一次经济普查数据能源消费与水资源消费的数据进行标准差和平均值的比较计算。认为北京应积极压缩耗能商、污染大的化学原料及化学制品制造业、黑色金属冶炼及压延工业、电力、热力的生产和供应业。实现产业的循环转型;高新技术产业的循环经济发展是北京市循环工业发展的关键环节;最后通过对重点生态工业示范园区的产业集群分析,提出今后北京重点发展的生态工业园。  相似文献   
577.
2012和2013年的废纸市场让很多企业一筹莫展,全球经济不振,国内需求不足,产能过剩,直接影响了造纸行业的生产和销售,作为原料供应商的废纸回收利用行业,必然受到连带影响,整个产业进入低迷阶段.除了外部经济环境的影响,行业内部应该如何调整,产业政策又该怎样引导行业健康发展,将是未来需要持续探讨的课题.  相似文献   
578.
ABSTRACT

This study employs Hugh Fearnley-Whittingstall’s television program, Hugh’s War on Waste, to explore representations of sustainable everyday life and the functions of celebrity environmental advocacy. The analysis is located within broader understandings of the discursive and contested nature of sustainability and the representative functions of environmental celebrities who act as figures of both distinction and equivalence. It discusses Fearnley-Whittingstall within the context of the stable of celebrity chefs, and it demonstrates how Hugh’s War on Waste is an example of the burgeoning televisual genre based on forms of campaigning about food issues. The analysis specifically explores how Hugh’s War on Waste is informed by: narratives of self-transformation where individuals are marshaled into appropriate practices of waste management and sustainability, presentations of the pleasures associated with such practices, and revelations of the networks of food production, distribution and consumption across the contexts of domestic everyday life, farms, supermarkets, and other corporations.  相似文献   
579.
作为“城市矿产”的典型代表,废弃手机因其废弃数量大、稀贵金属品位高等特性而备受关注,但在推进废弃手机回收过程中存在诸多问题。本文以推动产业发展为立足点,梳理了影响废弃手机回收的两级制衡要素,通过构建GREY-DEMATEL模型,定量评估各要素对废弃手机回收的影响程度并确定优先等级。其中,完善废弃手机回收的管理制度及相应的经济扶持政策成为短期内应着力解决的核心问题,从长期发展来看,废弃手机的前端收集应成为产业关注的重点。基于此,本文立足于废弃手机回收的短期目标及长远发展,分别提出相应的管理策略,为再生资源产业的良性发展提供对策建议。  相似文献   
580.
睢羽  宋守信 《火灾科学》2013,22(1):44-51
基于能量转移理论、多米诺效应理论等相关理论对地铁火灾二次事故概念进行界定,并分析地铁火灾二次事故的演化机理,确定地铁火灾条件下易发的二次事故类型;建立了地铁火灾二次事故安全评价指标体系,通过BP神经网络的安全评价方法对地铁火灾二次事故进行量化分析。  相似文献   
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