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Challenges, Volume 3, Issue 2 (December 2012), Pages 70-318

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Research

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Open AccessArticle Challenges and Opportunities in Developing Sustainable Communities in the North West of England
Challenges 2012, 3(2), 133-152; doi:10.3390/challe3020133
Received: 28 June 2012 / Accepted: 21 July 2012 / Published: 3 August 2012
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Abstract
Origins of sustainable communities lie in agendas set in a motion passed by the United Nations nearly forty years ago. As part of a sustainable development strategy and to tackle negative aspects of post industrial cities, in 2003, the UK government launched a
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Origins of sustainable communities lie in agendas set in a motion passed by the United Nations nearly forty years ago. As part of a sustainable development strategy and to tackle negative aspects of post industrial cities, in 2003, the UK government launched a Sustainable Communities Plan, accompanied by regional action plans, of which a major objective has been to implement regeneration projects aiming to improve quality of life in several areas of England, including the North West. This paper aims to review sustainable development agendas and to establish what needs to be done to improve quality of life indicators for communities of Stockbridge Village (SV), Murdishaw (M) and Halton Brook (HB) in Knowsley Metropolitan Borough (MBC) and Halton Borough Councils (BC), which have been identified as the most deprived post industrial areas in the North West of England. An investigation has been carried out by comparing the economic, social, physical and environmental indicators. Study findings reveal existing challenges and highlight problems that need to be addressed when implementing sustainable development strategy. Full article
Open AccessArticle Resilience, Sustainability and Risk Management: A Focus on Energy
Challenges 2012, 3(2), 153-182; doi:10.3390/challe3020153
Received: 1 May 2012 / Revised: 21 June 2012 / Accepted: 23 July 2012 / Published: 8 August 2012
Cited by 18 | PDF Full-text (583 KB) | HTML Full-text | XML Full-text
Abstract
The natural and subsequent human disasters of March 11, 2011 in Japan have brought into focus more than ever the importance of resilience and risk mitigation in the construction of energy infrastructure. This article introduces some of the critical issues and discusses the
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The natural and subsequent human disasters of March 11, 2011 in Japan have brought into focus more than ever the importance of resilience and risk mitigation in the construction of energy infrastructure. This article introduces some of the critical issues and discusses the implications of energy in alleviating or exacerbating the risks of natural disasters. Additionally, it presents a framework for considering the risks of energy systems from a broad perspective. The connection is drawn between design for sustainability and the risks associated with energy systems in natural disasters. As a result of the assessment, six criteria are proposed for energy systems to contribute to societal resilience in the face of natural disasters—they should be: (1) Continuous; (2) Robust; (3) Independent; (4) Controllable; (5) Non-hazardous; and (6) Matched to demand. Full article
(This article belongs to the Special Issue Risk Management Challenges: Mitigate the Risk from Natural Hazards)
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Open AccessArticle Assessing the Relationship Between Hazard Mitigation Plan Quality and Rural Status in a Cohort of 57 Counties from 3 States in the Southeastern U.S.
Challenges 2012, 3(2), 183-193; doi:10.3390/challe3020183
Received: 13 April 2012 / Revised: 27 July 2012 / Accepted: 28 July 2012 / Published: 13 August 2012
Cited by 2 | PDF Full-text (897 KB) | HTML Full-text | XML Full-text
Abstract
Rural counties face unique challenges with regard to disaster vulnerability and resilience. We compared the quality of hazard mitigation plans (HMPs) completed in accordance with provisions of the Disaster Mitigation Act of 2000 from 21 urban and 36 rural counties in three southeastern
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Rural counties face unique challenges with regard to disaster vulnerability and resilience. We compared the quality of hazard mitigation plans (HMPs) completed in accordance with provisions of the Disaster Mitigation Act of 2000 from 21 urban and 36 rural counties in three southeastern states. HMPs were content analyzed to calculate a score for six principles of plan quality. Generalized linear models were used to assess how the mean number of items within each of the six principles was related to urban status, adjusting for total county population and state-level differences. Adjusted mean ratios were higher in urban areas for goals, fact base, policies and participation. Rural areas performed better than urban counterparts in both implementation and monitoring and inter-organizational coordination. Our results suggest that there are important differences in hazard mitigation plan quality between urban and rural counties. Future research should explore characteristics of urban and rural counties that explain the observed differences, and whether such differences can help explain the inequalities in response and recovery to disasters between urban and rural counties. Full article
(This article belongs to the Special Issue Risk Management Challenges: Mitigate the Risk from Natural Hazards)
Open AccessArticle 5-Hydroxymethylfurfural (5-HMF) Production from Hexoses: Limits of Heterogeneous Catalysis in Hydrothermal Conditions and Potential of Concentrated Aqueous Organic Acids as Reactive Solvent System
Challenges 2012, 3(2), 212-232; doi:10.3390/challe3020212
Received: 25 July 2012 / Accepted: 22 August 2012 / Published: 13 September 2012
Cited by 25 | PDF Full-text (997 KB) | HTML Full-text | XML Full-text
Abstract
5-Hydroxymethylfurfural (5-HMF) is an important bio-sourced intermediate, formed from carbohydrates such as glucose or fructose. The treatment at 150–250 °C of glucose or fructose in pure water and batch conditions, with catalytic amounts of most of the usual acid-basic solid catalysts, gave limited
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5-Hydroxymethylfurfural (5-HMF) is an important bio-sourced intermediate, formed from carbohydrates such as glucose or fructose. The treatment at 150–250 °C of glucose or fructose in pure water and batch conditions, with catalytic amounts of most of the usual acid-basic solid catalysts, gave limited yields in 5-HMF, due mainly to the fast formation of soluble oligomers. Niobic acid, which possesses both Lewis and Brønsted acid sites, gave the highest 5-HMF yield, 28%, when high catalyst/glucose ratio is used. By contrast, we disclose in this work that the reaction of fructose in concentrated aqueous solutions of carboxylic acids, formic, acetic or lactic acids, used as reactive solvent media, leads to the selective dehydration of fructose in 5-HMF with yields up to 64% after 2 hours at 150 °C. This shows the potential of such solvent systems for the clean and easy production of 5-HMF from carbohydrates. The influence of adding solid catalysts to the carboxylic acid media was also reported, starting from glucose. Full article
(This article belongs to the Special Issue Challenges in Chemical Processes)
Open AccessArticle Towards a Casimir Force Measurement between Micromachined Parallel Plate Structures
Challenges 2012, 3(2), 261-277; doi:10.3390/challe3020261
Received: 4 September 2012 / Revised: 22 October 2012 / Accepted: 5 November 2012 / Published: 20 November 2012
Cited by 1 | PDF Full-text (2439 KB) | HTML Full-text | XML Full-text
Abstract
Ever since its prediction, experimental investigation of the Casimir force has been of great scientific interest. Many research groups have successfully attempted quantifying the force with different device geometries; however, measurement of the Casimir force between parallel plates with sub-micron separation distance is
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Ever since its prediction, experimental investigation of the Casimir force has been of great scientific interest. Many research groups have successfully attempted quantifying the force with different device geometries; however, measurement of the Casimir force between parallel plates with sub-micron separation distance is still a challenging task, since it becomes extremely difficult to maintain sufficient parallelism between the plates. The Casimir force can significantly influence the operation of micro devices and to realize reliable and reproducible devices it is necessary to understand and experimentally verify the influence of the Casimir force at sub-micron scale. In this paper, we present the design principle, fabrication and characterization of micromachined parallel plate structures that could allow the measurement of the Casimir force with tunable separation distance in the range of 100 to 1000 nm. Initially, a gold coated parallel plate structure is explored to measure the Casimir force, but also other material combinations could be investigated. Using gold-silicon eutectic bonding, a reliable approach to bond chips with integrated suspended plates together with a well-defined separation distance in the order of 1–2 μm is developed. Full article
Open AccessArticle From a Literature Review to an Alternative Treatment System for Landfill Gas and Leachate
Challenges 2012, 3(2), 278-289; doi:10.3390/challe3020278
Received: 16 October 2012 / Revised: 14 November 2012 / Accepted: 27 November 2012 / Published: 6 December 2012
Cited by 1 | PDF Full-text (656 KB) | HTML Full-text | XML Full-text
Abstract
This paper provides an alternative treatment system for landfill gas and leachate control in order to reduce the energy consumption and disposal cost, using the recycled landfill gas as the combustion promoter for incineration of the leachate. This study starts by providing a
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This paper provides an alternative treatment system for landfill gas and leachate control in order to reduce the energy consumption and disposal cost, using the recycled landfill gas as the combustion promoter for incineration of the leachate. This study starts by providing a literature review to summarize and analyze different approaches being applied to landfill leachate treatment. Subsequently, a conceptual prototype is proposed, which can be built using existing technology by means of technical possibility analysis, whilst economic benefits could be returned through preliminary comparison. With the proposed introduction of a “waste treatment park”, this alternative treatment system could provide a template for leachate and landfill gas control. This study may provide an insight for landfill operators and engineers to promote the transformation from the conceptual framework to the real achievement. Finally, the limitations of the conceptual model and analysis are discussed, laying a foundation for further work. Full article

Review

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Open AccessReview Improving Product Quality with Entrapped Stable Emulsions: From Theory to Industrial Application
Challenges 2012, 3(2), 84-113; doi:10.3390/challe3020084
Received: 10 May 2012 / Revised: 15 June 2012 / Accepted: 25 June 2012 / Published: 10 July 2012
Cited by 3 | PDF Full-text (995 KB) | HTML Full-text | XML Full-text
Abstract
Entrapment of sub-micron scale emulsions containing active ingredients into macro-scale matrices has exhibited great potential as a delivery vehicle with controlled release capabilities, however optimization remains unrealized. Reported here are methods used to improve product quality by optimizing the emulsion formation steps. These
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Entrapment of sub-micron scale emulsions containing active ingredients into macro-scale matrices has exhibited great potential as a delivery vehicle with controlled release capabilities, however optimization remains unrealized. Reported here are methods used to improve product quality by optimizing the emulsion formation steps. These methods are in conjunction with the precepts of Process Intensification (PI). Success with pharmaceutics and chemical reacting systems provides a strategy for a wide range of applications; the emphasis here being nutraceutics. Use of a nano-technology platform assists in: (a) product quality improvements through better nutrient dispersion, and thus bio-efficacy; and (b) production efficiencies through implementation of PI concepts. A continuous methodology, utilizing these PI concepts, that approximates a bottom-up approach to the creation of sub-micron and nano-emulsions is the basis of the technology presented here. Note that solid particles may result during post-processing. The metrics of successful processing include obtainment of nano-scale species with minimal input energy, reduced processing steps at higher throughput rates, and improved quality without over-usage of key ingredients. In addition to flavor and wellness characteristics, product stability for extended shelf life along with an appreciable cargo load in the entrapped emulsion is a major concern. Experimental protocols and path forward recommendations to overcome challenges and meet expectations in these emerging opportunities are also presented. Full article
(This article belongs to the Special Issue Challenges in Chemical Processes)
Open AccessReview Continuous-Flow Processes in Heterogeneously Catalyzed Transformations of Biomass Derivatives into Fuels and Chemicals
Challenges 2012, 3(2), 114-132; doi:10.3390/challe3020114
Received: 11 May 2012 / Revised: 19 June 2012 / Accepted: 11 July 2012 / Published: 12 July 2012
Cited by 6 | PDF Full-text (678 KB) | HTML Full-text | XML Full-text
Abstract
Continuous flow chemical processes offer several advantages as compared to batch chemistries. These are particularly relevant in the case of heterogeneously catalyzed transformations of biomass-derived platform molecules into valuable chemicals and fuels. This work is aimed to provide an overview of key continuous
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Continuous flow chemical processes offer several advantages as compared to batch chemistries. These are particularly relevant in the case of heterogeneously catalyzed transformations of biomass-derived platform molecules into valuable chemicals and fuels. This work is aimed to provide an overview of key continuous flow processes developed to date dealing with a series of transformations of platform chemicals including alcohols, furanics, organic acids and polyols using a wide range of heterogeneous catalysts based on supported metals, solid acids and bifunctional (metal + acidic) materials. Full article
(This article belongs to the Special Issue Challenges in Chemical Processes)
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Open AccessReview Particle Handling Techniques in Microchemical Processes
Challenges 2012, 3(2), 194-211; doi:10.3390/challe3020194
Received: 27 July 2012 / Accepted: 14 August 2012 / Published: 22 August 2012
Cited by 12 | PDF Full-text (3212 KB) | HTML Full-text | XML Full-text
Abstract
The manipulation of particulates in microfluidics is a challenge that continues to impact applications ranging from fine chemicals manufacturing to the materials and the life sciences. Heterogeneous operations carried out in microreactors involve high surface-to-volume characteristics that minimize the heat and mass transport
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The manipulation of particulates in microfluidics is a challenge that continues to impact applications ranging from fine chemicals manufacturing to the materials and the life sciences. Heterogeneous operations carried out in microreactors involve high surface-to-volume characteristics that minimize the heat and mass transport resistances, offering precise control of the reaction conditions. Considerable advances have been made towards the engineering of techniques that control particles in microscale laminar flow, yet there remain tremendous opportunities for improvements in the area of chemical processing. Strategies that have been developed to successfully advance systems involving heterogeneous materials are reviewed and an outlook provided in the context of the challenges of continuous flow fine chemical processes. Full article
(This article belongs to the Special Issue Challenges in Chemical Processes)
Open AccessReview A Life-cycle Approach to Improve the Sustainability of Rural Water Systems in Resource-Limited Countries
Challenges 2012, 3(2), 233-260; doi:10.3390/challe3020233
Received: 10 August 2012 / Revised: 29 October 2012 / Accepted: 31 October 2012 / Published: 8 November 2012
Cited by 3 | PDF Full-text (488 KB) | HTML Full-text | XML Full-text
Abstract
A WHO and UNICEF joint report states that in 2008, 884 million people lacked access to potable drinking water. A life-cycle approach to develop potable water systems may improve the sustainability for such systems, however, a review of the literature shows that such
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A WHO and UNICEF joint report states that in 2008, 884 million people lacked access to potable drinking water. A life-cycle approach to develop potable water systems may improve the sustainability for such systems, however, a review of the literature shows that such an approach has primarily been used for urban systems located in resourced countries. Although urbanization is increasing globally, over 40 percent of the world’s population is currently rural with many considered poor. In this paper, we present a first step towards using life-cycle assessment to develop sustainable rural water systems in resource-limited countries while pointing out the needs. For example, while there are few differences in costs and environmental impacts for many improved rural water system options, a system that uses groundwater with community standpipes is substantially lower in cost that other alternatives with a somewhat lower environmental inventory. However, a LCA approach shows that from institutional as well as community and managerial perspectives, sustainability includes many other factors besides cost and environment that are a function of the interdependent decision process used across the life cycle of a water system by aid organizations, water user committees, and household users. These factors often present the biggest challenge to designing sustainable rural water systems for resource-limited countries. Full article
(This article belongs to the Special Issue Challenges in Industrial Ecology)
Open AccessReview Challenges in Improving Energy Efficiency in a University Campus Through the Application of Persuasive Technology and Smart Sensors
Challenges 2012, 3(2), 290-318; doi:10.3390/challe3020290
Received: 4 September 2012 / Revised: 8 November 2012 / Accepted: 9 November 2012 / Published: 19 December 2012
Cited by 3 | PDF Full-text (2344 KB) | HTML Full-text | XML Full-text | Correction | Supplementary Files
Abstract
The impact of energy consumption and carbon emission in the UK poses a grave challenge. This challenge is particularly high amongst residents of university campuses, where usage of electricity and carbon emission remain invisible to the students. In student residential accommodation, personal choices
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The impact of energy consumption and carbon emission in the UK poses a grave challenge. This challenge is particularly high amongst residents of university campuses, where usage of electricity and carbon emission remain invisible to the students. In student residential accommodation, personal choices and social influences affect electricity consumption and ultimately the resultant reduction in carbon emissions. Therefore, innovative solutions are required to change students’ energy consumption behavior, and one promising part of the solution is to present real-time electricity consumption data to students in real-time via a dedicated web platform, while, at the same time, appointing an energy delegate in each hall to induce motivation among the students. The results of some interventions show that immediate energy feedback from smart meters or display devices can provide savings of 5%–15%. However, the situation is different; with the complexity in behavior of our target groups “the students who are living in the halls of residence”, there are economical and environmental aspects to be addressed in these issues, in the campus halls of residence. Therefore, we propose a system to address this issue, by applying smart sensors (real-time electricity data capture), integration of dedicated visual web interface (real-time electricity feedback display) and an appointed energy delegate in each hall (a motivator). It is expected that this will motivate students living in the halls of residence to reduce their electricity wastage and, therefore, control the energy cost and also reduce the carbon emissions released into the environment. In the present research, we focus on the University of Kent, Canterbury campus to study energy conservation and carbon emission reduction strategies. Full article
(This article belongs to the Special Issue Challenges in Industrial Ecology)

Other

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Open AccessDiscussion Syndicate Innovation Venturing: Translating Academic Innovations into Commercial Successes
Challenges 2012, 3(2), 70-83; doi:10.3390/challe3020070
Received: 26 March 2012 / Revised: 21 May 2012 / Accepted: 24 May 2012 / Published: 5 July 2012
Cited by 2 | PDF Full-text (150 KB) | HTML Full-text | XML Full-text
Abstract
Innovations that initiate new technology cycles, i.e., radical innovations, bring tremendous value to Society and build for the companies that deploy them sustainable competitive advantages. However, large firms have typically been relatively inefficient at accessing from academia or technology start-ups such technological
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Innovations that initiate new technology cycles, i.e., radical innovations, bring tremendous value to Society and build for the companies that deploy them sustainable competitive advantages. However, large firms have typically been relatively inefficient at accessing from academia or technology start-ups such technological leaps. Indeed, most multiyear and multimillion dollar academia-industry partnerships have historically not resulted in any acceleration of the rate of deployment of game-changing innovations, which empirically proceeds in 25 year cycles, such as for example the expansion of the scope of the pharmaceutical industry from small molecules to biologics, or, projecting into the future, to siRNA or therapeutic stem cell technologies. Syndicated innovation venturing is a new strategic partnering concept described here that brings together actors from different economic segments in a non zero-sum game as a means to facilitate seed-funding, with the aim to de-risk technologies while reducing initial financial exposures. A case study in the pharmaceutical industry suggests that alleviating this hurdle may provide an appropriate environment to improve the dynamics of academic technology transfer to the commercial phase. By contributing to the de-risking of the creation of novel biotechnology businesses, this novel mechanism could help speed up the commercialization of emerging technologies on a large scale. At a time when knowledge-based firms such as pharmaceutical companies attempt to revisit their innovation models to advance science, in spite of an environment of increasing risk-aversion, such responses could tilt the balance in favor of disruptive products and sustained corporate financial performance by removing common barriers to radical innovation deployment. Full article

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