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Shared risks and opportunities set specific premises for risk management (RM) in temporary multi-organizations (TMOs). However, most project RM research is presented from the perspective of a single-organizational project delivery team or covers limited risk perceptions and RM approaches. This paper aims to address how well the body of knowledge on multi-organizational RM corresponds to a state-of-art understanding on project RM and to identify which gaps need to be addressed in future research. The review involves: 1) the preferred view of risk as threat and/or opportunity, 2) the nature of addressed risks as anticipated or unanticipated risks or unrealistic assumptions, 3) the role of the multi-organization as the source of risks and/or resources for risk management (RM), and 4) the allocation of risk responsibilities. The review covers research papers published between 2000 and 2012 in four journals: International Journal of Project Management (IJPM), Project Management Journal (PMJ), Journal of Construction Engineering and Management (JCEM), and IEEE Transactions on Software Engineering (TSE). 105 eligible research papers were identified. The results and conclusion outline the identified main gaps in multi-organizational RM research compared to the state-of-art RM research and TMO-specific characteristics. The results can be used to inform research agendas on more holistic and dynamic multi-organizational RM concepts.  相似文献   
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The redox behavior of iron oxide modified with various amount of molybdenum (Mo) was investigated in the present study. The modified iron oxides were prepared by co-precipitation using urea hydrolysis method. The influence of Mo on the hydrogen production capacity and the material stability was studied in detail employing temperature-programmed reduction (TPR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET analysis. Furthermore, the activity and the stability of the samples were tested in repeated reduction and re-oxidation for 100 cycles with diluted H2 and H2O. The results indicate that Mo enhances the stability of iron oxide material by mitigating the sintering process. The positive influence of Mo in stabilizing the iron oxide material is attributed to the dispersion of Fe–Mo oxide material. The dispersion in turn inhibits the neck formation responsible for the sintering.  相似文献   
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A dynamic model of a multiple hearth kaolin calciner has been developed and is presented in this article. This model describes the physical‐chemical phenomena taking place in the six furnace parts: the solid phase, gas phase, walls, cooling air, rabble arms, and the central shaft. The solid phase movement, in particular, is described by a novel mixing model. The mixing model divides the solid bed in a hearth into volumes and the distribution of their contents, after one full central shaft rotation, is identified by the pilot experiments. First, the model is validated by the industrial data, and then the dynamics of the multiple hearth furnace is studied by introducing step changes to the three manipulated variables: the feed rate, and the gas, and air flows supplied. The responses of the gas phase temperature and solid bed component profiles are analysed and the results are discussed. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3683–3698, 2015  相似文献   
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The present study examines Chinese university students’ attitudes and knowledge regarding energy, specifically towards forest bio-energy in their country. The study was based on opinions of students from Northwest Agriculture and Forestry University (NWAFU) in China and it was conducted using a questionnaire completed by 441 students. The students’ attitudes are seen as highly relevant because they are considered as both potential consumers and possible experts in the field of bio-energy. Their activities influence how the future energy markets will likely develop. The results revealed various interesting facets of the students’ views regarding energy usage. Of particular interest is the students’ positive attitude towards renewable energy in general, but slightly less positive towards forest bio-energy. However, the respondents expected to receive more information and knowledge about renewable energy and forest bio-energy. Moreover, it can be concluded that the dissemination of knowledge through different sources (e.g. teaching in school, information available on the Internet and other media channels) is an increasingly important aspect regarding energy issues. The results of this study can provide information of the perceptions of young educated people on energy policy issues and thus serve political decision-making processes for the future options concerning the development of forest bio-energy in China. Finally, the outcome of this study indicates that further environmental and energy education in China is urgently needed.  相似文献   
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Health-related information is increasingly used on food products to convey their benefits. Health claims as a subcategory of these messages link the beneficial component, functions or health outcomes with specific products. For consumers, health claims seem to carry the message of increased healthiness, but not necessarily making the product more appealing. The wording of the claim seems to have little impact on claim perception, yet the health image of carrier products is important. From consumer-related factors the relevance and attitudes towards functional foods play a role, whereas socio-demographic factors have only minor impact and the impact seems to be case-dependent. Familiarity with claims and functional foods increase perceived healthiness and acceptance of these products. Apparently consumers make rather rational interpretations of claims and their benefits when forced to assess the information, but we still know relatively little about consumer understanding of the message content in claims and even less about the assessment of personal relevance of the claimed benefits. In future studies more emphasis should be put on including contextual influences and realistic conditions in assessing consumer understanding and use of health claims in purchase decisions.  相似文献   
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The aim of this study is to discuss how information about the development and use of bio-energy is forwarded and disseminated to general public via the Internet in China. Furthermore, this study also explores in what manner the information of renewable energy policies is presented. A research method used in this study is an application of content analysis. Altogether 19 energy-related web platforms were found by searching keywords, such as “energy net” or “renewable energy net” or “bio-energy net” on www.Google.cn. A thorough analysis was conducted by focusing on one of them: www.china5e.com. The news articles on www.china5e.com were examined according to whether the use of bio-energy was articulated positively or negatively in the contents of articles. It was also considered whether the articles were imported from abroad. The results of this study indicated that in China there is a tendency on the Internet to disseminate primarily the positive information about bio-energy with a great emphasis on its benefits. In addition, the study shows that when analyzing the content of the news articles, biogas and liquid bio-fuels will be the main bio-energy development trends in China in the near future.  相似文献   
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Abstract Fungal spore content in dust accumulated in air ducts was investigated in 24 mechanically ventilated single-family houses of which 15 had also a central air heating system. Dust was collected from the ducts simultaneously with cleaning of the ventilation systems. Besides spore concentrations and flora of culturable fungi, total fungal spore concentrations were determined in dust samples by the aqueous two-phase technique and spore counting with epifluorescence microscopy. Culturable spore concentrations in the dust varied from 104 to 107 CFU/g and total spore concentrations from 107 to 108 spores/g. Total spore concentrations in the duct dust were significantly higher in the air heated houses than in the other mechanically ventilated houses. The difference resulted mainly from a higher proportion of recirculation air and a higher age of the air heated houses. Cladosporium, Penicillium, Aspergillus and yeasts consisted of >90% of fungal flora in the dust. Although total spore concentrations were at the same level both in the exhaust and in the supply ducts in both types of house, culturable fungal spore concentrations were slightly higher in the exhaust ducts than in the supply ducts. The proportion of culturable spores was <5% of total spores in dust accumulated in the ducts.  相似文献   
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Mine Water and the Environment - The mobility of contaminants from mine waste can be assessed using different extraction methods. Aqua regia (AR) extraction is the most commonly used method in...  相似文献   
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