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31.
Matheus D. Slongo Suelen D. F. Brandolt Tales S. Daitx Raquel S. Mauler Marcelo Giovanela Janaina S. Crespo Larissa N. Carli 《Journal of Polymers and the Environment》2018,26(6):2290-2299
The aim of this work was to evaluate the effect of different plasticizers on the morphology, crystallization, and mechanical properties of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV)/organomodified montmorillonite (OMt) nanocomposites. We investigated three different plasticizers: dioctyl phthalate (DOP), a commonly used additive in the polymer industry, and two natural and biodegradable plasticizers: epoxidized soybean oil (ESO) and triethyl citrate (TEC). The nanocomposites with 3 wt% OMt were obtained by melt processing in an internal mixer. The plasticizers were used alone or in combination with clay in a concentration of 10 wt%. X-ray diffraction and scanning electron microscopy results revealed a partially intercalated structure. The degree of crystallinity was higher for all of the samples compared to neat PHBV, although the melting temperature decreased with the use of plasticizers combined with OMt. The impact strength results were dependent on the interaction between the components of the system. Triethyl citrate was the most effective plasticizer due to its more pronounced interaction with the PHBV matrix, which yielded improvements in processing conditions and PHBV’s flexibility and impact properties. 相似文献
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This paper explores three questions related to acceptance as a security management approach. Acceptance draws upon relationships with community members, authorities, belligerents and other stakeholders to provide consent for the presence and activities of a non‐governmental organisation (NGO), thereby reducing threats from these actors. Little is documented about how NGOs gain and maintain acceptance, how they assess and monitor the presence and degree of acceptance, or how they determine whether acceptance is effective in a particular context. Based on field research conducted in April 2011 in Kenya, South Sudan and Uganda, we address each of these three issues and argue that acceptance must be actively sought as both a programme and a security management strategy. In the paper we delineate elements common to all three contexts as well as missed opportunities, which identify areas that NGOs can and should address as part of an acceptance approach. 相似文献
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Levels of dechlorane plus and polybrominated diphenylethers in human milk in two Canadian cities 总被引:1,自引:0,他引:1
Siddique S Xian Q Abdelouahab N Takser L Phillips SP Feng YL Wang B Zhu J 《Environment international》2012,39(1):50-55
Flame retardant dechlorane plus (DP) and several polybrominated diphenylether (PBDE) congeners have been measured in 87 human milk samples collected in two Canadian cities: Kingston and Sherbrooke. The levels of PBDEs in human milk (mean (median), ng g− 1 lipid weight = 10 (5.9), 4.1 (2.8), 3.0 (1.6), 5.12 (1.6), and 15 (ND) for BDE-47, BDE-99, BDE-100, BDE-153, and BDE-209, respectively) were comparable to those reported in Europe, U.S.A. and China. The levels of DP, with a mean value of 0.98 ng g− 1 and a median value of 0.60 ng g− 1 (lipid weight), were two to ten times lower than those of concurrently measured major PBDEs including BDE-209. While there is little difference in the levels of measured contaminants in milk samples collected from the two cities, the contaminants levels in human milk show, indicated by Principal Components Analysis, that DP, deca-BDE, and penta-BDE come from three distinct sources. The mean and median isomer ratio values of DP in milk were 0.67 and 0.69, respectively, very similar to that of DP commercial products. 相似文献
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La Fuente Carla I. A. do Val Siqueira Larissa Augusto Pedro Esteves Duarte Tadini Carmen C. 《Journal of Polymers and the Environment》2022,30(9):3974-3984
Journal of Polymers and the Environment - Green methods of modification, such as ozone, can bring new functionalities to starch. In this study, starch-based plastics were produced by extrusion,... 相似文献
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Sandro Donnini Mancini Alex Rodrigues Nogueira Dennis Akira Kagohara Jonas Age Saide Schwartzman Tania de Mattos 《Waste management & research》2007,25(6):517-523
The urban solid waste of the city of Indaiatuba (pop. 175 000), located in the state of S?o Paulo, was characterized, focusing on the recycling potential. For this purpose, collected waste was subdivided into 27 items, classified by mass and volume. About 90% of this waste was found to be potentially recyclable and only 10% requiring landfilling. The compostable organic matter, in the form of food and garden waste, both with high moisture content (51 and 41%, respectively), represents 54% in mass and 21% in volume. The most common type of plastic in this waste is high density polyethylene, whose estimated disposal is about 5000kgday(-1). A socio-economic analysis of the waste generation indicates that low-income neighbourhoods discard relatively less packaging and more food waste, shoes and construction debris than middle and high income ones, which may be due to low purchasing power and schooling. Our findings indicate that more aluminium and uncoloured polyethylene terephthalate is discarded in the warmest months of the year, probably due to a greater consumption of canned and bottled drinks. 相似文献
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GC/MS-screening analyses of water samples from the Lippe River, Germany, revealed the presence of a wide spectrum of low-molecular weight organic compounds ranging from non-polar constituents like aliphatic hydrocarbons to polar constituents like n-carboxylic acids and phenols. Most of the identified compounds could be attributed to anthropogenic input and are used as plasticizers, flame retardants, pharmaceutical drugs or fragrances. Some of them had rarely been noticed as organic pollutants of aquatic environments before. These are, among others, 9-methylacridine, the plasticizer 2,2,4-trimethyl-1,3-pentandioldiisobutyrate (TXIB), the surfactant 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD), triphenylphosphinoxide and the flame retardant tris(chloropropyl)phosphate. On the other hand, most of the identified trialkyl phosphates, pharmaceutical drugs and synthetic fragrances have been reported in surface waters by several authors so far. Input pathways of the detected compounds were traced back by sampling various input sources of organic matter such as discharges of wastewater and Lippe River tributaries. Several contaminants were ubiquitous in Lippe River water and also occurred in sewage effluent from a municipal sewage treatment plant and in samples from the tributaries. This observation suggests that they are typical sewage derived contaminants and have the potential to be used as anthropogenic molecular markers. 相似文献
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Georgia Carvalho Paulo Moutinho Daniel Nepstad Luciano Mattos Márcio Santilli 《Mitigation and Adaptation Strategies for Global Change》2000,5(4):411-411
Authors Index
Author index 相似文献39.
Surprisingly little attention is paid to the role of digital technology and related forms of data production, storage, processing, and sharing in humanitarian governance. This paper uses Michael Barnett's ( 2013 ) conceptualisation of humanitarian governance when arguing for a better accounting of technology in literature on humanitarian governance. Specifically, it proposes a two‐fold alertness to governance of (a) the uses of new technology and (b) that which is produced by digital technologies. This elucidates important issues, including that of access to digitalised data collected from humanitarian subjects, with implications for their (in)security. The paper concludes by suggesting that access is no longer ‘only’ about challenges of gaining access to vulnerable populations, but also about challenges of preventing access to vulnerable digital bodies and their use for aggressive purposes. In short, access and protection acquire a new dimension and analyses of humanitarian governance must be more attentive to the role of digital technology. 相似文献
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Despite abundant research on the consequences of perceived abusive supervision, less is known about how employees develop perceptions of supervisory abuse. Across two studies, we integrate classic and recent theoretical work on attributions to understand the causal explanations underlying employee perceptions of and reactions to abusive supervision. In the first study, we develop measures of internal, external, and relational attributions for perceived supervisor abuse. In the second study, we demonstrate that internal and external attributions are indirectly related to aggressive and citizenship behaviors through employees' perceptions of interactional justice. Theoretical and practical implications are also discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献