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871.
Starch-based composite films have been proposed as food packaging. In this context, the study of non-conventional starch sources (sagu, Canna edulis Kerr) has worldwide special attention, because these materials can impart different properties as carbohydrate polymers. A thorough study of the matrices used (sagu starch and flour) was carried out. In the same way, thermoplastic starch (TPS)/PCL blend and thermoplastic flour (TFS)/PCL blend were obtained by melt mixing followed by compression moulding containing glycerol as plasticizer. In this study, chemical composition of the matrices and their properties were related with the properties of the developed films. Moisture content, water solubility, X-ray diffraction, thermogravimetric analysis and mechanical and microstructural properties were evaluated in the films. Taking into account the results, the sagu flour has great potential as starchy source for food packaging applications. However, concretely the flour had lower compatibility with the PCL compared to the starch/PCL blend. 相似文献
872.
Rudi Dungani Abdulwahab F. Owolabi Chaturbhuj K. Saurabh H. P. S. Abdul Khalil Paridah M. Tahir C. I. C. M. Hazwan Kamoldeen A. Ajijolakewu M. M. Masri E. Rosamah P. Aditiawati 《Journal of Polymers and the Environment》2017,25(3):692-700
The objective of this work was to isolate cellulose nanocrystal (CNC) from oil palm fronds (Elaeis guineensis) and its subsequent characterization. Isolation involves sodium hydroxide/anthraquinone pulping with mechanical refining followed by total chlorine free bleaching (includes oxygen delignification, hydrogen peroxide oxidation and peracetic acid treatment) before acid hydrolysis. Bleaching significantly decreased kappa number and increased α-cellulose percentage of fibers as confirmed by Technical Association of the Pulp and Paper Industry standards. Transmission electron microscopy (TEM), X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis revealed that acid hydrolysis along with bleaching improved crystallinity index and thermal stability of the extracted nanocrystals. It was observed that CNC maintained its cellulose 1 polymorph despite hydrolysis treatment. Mean diameter as observed by TEM and average fiber aspect ratio of obtained CNC was 7.44 ± 0.17 nm and 16.53 ± 3.52, respectively making it suitable as a reinforcing material for nanocomposite. 相似文献
873.
Compositions of wood-polypropylene composites (WPCs) are prepared through melt compounding followed by injection moulding. WPCs are formulated for eight compositions with a different weight ratio of wood, virgin or recycled polypropylene and coupling agent. WPCs compositions are compared in terms of Melt Flow Index, Tensile, FESEM images, Flexural and crystallinity index for same operating variable conditions. From the results, recycled polypropylene based WPCs are superior in comparison to virgin polypropylene based WPCs. With the addition of 5 % coupling agent in recycled polypropylene-based composites for 45:50 composition, tensile and flexural values of WPCs are higher in comparison to all composition and neat virgin or recycled polypropylene. This work stands for the utilization of waste wood with recycled plastic for replacement of wood and virgin plastic. 相似文献
874.
Bovine Tuberculosis and Badger Culling in England: An Animal Rights-Based Analysis of Policy Options
Steven P. McCulloch Michael J. Reiss 《Journal of Agricultural and Environmental Ethics》2017,30(4):535-550
Bovine tuberculosis (bovine TB) is an important and controversial animal health policy issue in England, which impacts humans, cattle and badgers. The government policy of badger culling has led to widespread opposition, in part due to the conclusions of a large field trial recommending against culling, and in part because badgers are a cherished wildlife species. Animal rights (AR) theorists argue that sentient nonhumans should be accorded fundamental rights against killing and suffering. In bovine TB policy, however, pro-culling actors claim that badgers must be culled to avoid the slaughter of cattle. The first part of the paper compares AR theories of Regan, Francione, Cochrane, Garner and Donaldson and Kymlicka in the context of wildlife species. The second part of the paper applies these AR theories to bovine TB and badger control. AR theories are applied to badger control policy options of (1) do nothing, (2) badger culling, and (3) badger vaccination. We conclude that AR theories are strongly opposed to badger culling. In general, culling is prohibited due to a badger’s right to life and its rights against suffering. The AR theories support a do-nothing, i.e. non-culling, non-vaccination approach to badger control. In the case of the AR theories of Regan and Francione, this is based on abolitionist positions with respect to farming. For Cochrane, Garner, and Donaldson and Kymlicka, the do-nothing policy option is preferred because badger vaccination causes a degree of suffering which generally is not for the individual’s benefit. 相似文献
875.
Moti Gorin 《Journal of Agricultural and Environmental Ethics》2017,30(4):585-594
Utilitarian objections to the consumption of factory-farmed products center primarily on the harms such farms cause to animals. One problem with the utilitarian case against the consumption of factory-farmed products is that the system of production is so vast and complex that no typical, individual consumer can, through her consumer behavior, make any difference to the welfare of animals. I grant for the sake of argument that this causal inefficacy objection is sound and go on to argue that the utilitarian nevertheless has the resources to conclude that at least in some cases it is wrongful on utilitarian grounds for an individual to consume factory-farmed products. When a consumer who believes that factory farming is wrongful consumes the products of factory farms, she endorses wrongful practices, and by doing so she engages in a form of self-harm. Self harm, like harm to others, must be taken into consideration when a utilitarian agent deliberates about the permissibility of her proposed course of action. Therefore, the causal inefficacy objection, while powerful, is not decisive against utilitarian objections to consuming factory-farmed products. 相似文献
876.
S. Gómez Mestres Marianne E. Lien 《Journal of Agricultural and Environmental Ethics》2017,30(5):625-643
This paper explores food commoning through an ethnographic case study in Catalonia as our primary site while the Norwegian case is juxtaposed as a comparison, two agriculturally and economically different European countries. The ethnography analyses cooperation networks between organic food producers’ and consumers’ involving different nodes of community gardening initiatives, self-employed growers, local farmers and all of them under a unique cooperative integrating a community economy. The result it is a myriad of exchange practices ranging from reciprocity and barter to market exchange without intermediaries through on-line platforms. Along these exchanges different options of currency intervene giving rise to novel social and cooperative relations. Similar initiatives in Norway show less variation and are less experimental regarding forms of payment but share similarities in relation to material articulations, concerns and forms of alternative practice. Although these novel forms do not represent a complete break from the more standardized supply chains, and hence from the oppositions/contradictions of production and consumption, the participants see themselves as contributing to a more general process of de-commodification of food. We explore the extent to which the meaning and moral values are mutually constituted in relation to socioeconomic exchanges and environmental caring that each person experiences based on different forms of cooperation and reciprocity. Food, we suggest, is more than a commodity on the market that we may influence through our role as consumers. It is a significant focal point connecting our lives to those of others that articulates one’s relations to society in a political manner. 相似文献
877.
Kalpita Bhar Paul 《Journal of Agricultural and Environmental Ethics》2017,30(5):645-665
Rapid changes in the environment are far from being a new phenomenon, especially for vulnerable zones like the Sundarbans, India. In the era of climate change, when these islands are witnessing a lot of initiatives to combat the increasing negative impacts of various environmental changes, this article showcases why it is imperative to study the everyday phenomenological experiences of the islanders to be able to go beyond the climate-affected narratives and generate a deeper understanding of the phenomenon itself—‘environmental change’. This article provides the islanders’ phenomenological accounts of environmental change and borrowing from Heidegger’s concept of ‘Being-in-the-world’ explicates the reason behind the disparity in acknowledging environmental change across individuals. Making this interpretive phenomenological account of environmental change as the ground, this article offers a rubric of community-based ethic which perhaps can prove to be effective in addressing any place-specific environmental change, over and above the prevalent approach of place-based ethic. 相似文献
878.
Urban farming – a type of urban agriculture focused on entrepreneurial food production – serves multiple functions in neighbourhoods; yet these are not well delineated. Expectations for urban farming often centre on traditional measures of economic development, potentially overlooking other benefits. Through a qualitative case study conducted in Baltimore, Maryland, we sought to understand community perceptions regarding the ways in which urban farms can benefit cities. Interviews with residents, neighbourhood leaders, and urban farmers in three residential neighbourhoods with urban farms revealed the pathways by which community members view farms as improving neighbourhoods. Benefits stemmed from four primary changes urban farms made to study neighbourhoods: creation of public projects welcoming involvement, physical improvement of degraded space, production of local food, and creation of new businesses. These changes led to multiple perceived benefits including increased social connectedness, a transformed physical landscape, improved neighbourhood reputation, increased access to fresh produce, and educational, youth development, and employment opportunities. Our findings demonstrate the importance of a multifunctional paradigm that accounts for social and educational functions in assessing the value of urban farming and bring empirical evidence to the concept of multifunctional agriculture. Urban farms with strong social aims may appear to contribute little to economic development if measured using traditional indicators of success such as job creation or fiscal impacts, but provide numerous other benefits for community development. 相似文献
879.
The northern, resource-dependent regions of Canada have long faced distinctive social, economic, and environmental challenges and vulnerabilities. However, these regions and communities increasingly find themselves in a transitional and post-productivist context – the implications of which are largely unclear. Therefore, research is needed to identify the current and emerging challenges facing such regions and how environmental governance and planning must adjust to meet these challenges. We utilise the case study of the Northeast Superior region of Ontario to identify and analyse the dynamics developing in post-productivist, resource-dependent regions and what the implications may be for environmental governance. Several key themes and issues that emerged include an increasingly pluralistic context, new regionalism and north–south tensions, First Nation initiatives and power imbalances, and northern identities which are tied to ideas of historical resource-dependence, remoteness, and intimate and complex links to the landscape, all of which inform environmental governance and sustainability debates. As a result, the Northeast Superior case provides insight into these ongoing dynamics which encompass individuals, government, industry, organisations, and the landscape, with the resultant lessons being transferable to initiatives in other northern, remote, and circumpolar regions. 相似文献
880.
James W. Yeates 《Journal of Agricultural and Environmental Ethics》2017,30(1):23-35
The Farm Animal Welfare Council’s concept of a Good Life gives an idea of an animal’s quality of life that is over and above that of a mere life worth living. The concept needs explanation and clarification, in order to be meaningful, particularly for consumers who purchase farm animal produce. The concept could allow assurance schemes to apply the label to assessments of both the potential of each method of production, conceptualised in ways expected to enhance consumers’ engagement such as ‘naturalness’ and ‘freedom’; and the concept of a life worth living as a safeguard threshold below which no animal’s actual welfare should fall, based on each animal’s overall affective states. This may provide a framework for development of the Good Life concept, within scientific and sociological fields, in order to allow reliable and influential use by assessors, consumers and retailers. 相似文献