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131.
In the present investigation, microfibrils were extracted from raw bamboo and characterized using scanning electron microscope. Composites based on polyhydroxybutyrate (PHB) and bamboo microfibril were prepared with various microfibril loading. The mechanical and thermal properties of the resulting composites were measured. Tensile strength and impact strength of the composites were found to be increasing with increase in the loading of bamboo microfibrils, reached an optimum and thereafter decreased with further increase in microfibril loading. Percentage crystallinity was found to be increasing with increase in fibril loading. Thermal stability of the composite was higher than that of pure PHB. The composite could be developed further for various structural applications.  相似文献   
132.
In the present study we investigate the fate of citalopram (CIT) at neutral pH using advanced water treatment technologies that include O3, ClO2 oxidation, UV irradiation and Fenton oxidation. The ozonation resulted in 80% reduction after 30 min treatment. Oxidation with ClO2 removed >90% CIT at a dosage of 0.1 mg L−1. During UV irradiation 85% reduction was achieved after 5 min, while Fenton with addition of 14 mg L−1 (Fe2+) resulted in 90% reduction of CIT. During these treatment experiments transformation products (TPs) were formed from CIT, where five compounds were identified by using high resolution and tandem mass spectrometry. Among these desmethyl-citalopram and citalopram N-oxide have been previously identified as human metabolites, while three are novel and published here for the first time. The three TPs are a hydroxylated dimethylamino-side chain derivative, a butyrolactone derivative and a defluorinated derivative of CIT.  相似文献   
133.
The aim of the study was to investigate the hypothesis that consumption of fish liver increases cancer risk in humans due to increased intake of persistent organic pollutants (POPs). This study is based on data from the Norwegian Women and Cancer Study (NOWAC). The study has a prospective cohort design with questionnaire data from 64 285 randomly selected Norwegian women (aged 40-70 at baseline) and linkage to the Norwegian Cancer Registry. Cox proportional hazards regression was used to calculate risk ratios associated with consumption of fish liver and total cancer and cancer in breast, uterus, and colon. Fish liver consumption was, after adjusting for known risk factors, associated with a significant reduced risk for total cancer (RR = 0.92, 95% CI: 0.85, 0.99), and non-significant reduced risk for breast cancer (RR = 0.90, 95% CI: 0.78, 1.04), and colon cancer (RR = 0.82, 95% CI: 0.63, 1.07). Relative risk for uterus cancer was 0.82 (95% CI: 0.61-1.12). No significant dose-response effect was found for frequency of fish liver consumption (when divided into three intake groups) and total cancer, nor for any of the other cancer sites.We have concluded that in Norwegian women, fish liver consumption was not associated with an increased cancer risk in breast, uterus, or colon. In contrast, a decreased risk for total cancer was found.  相似文献   
134.
The photochemical ozone creation potentials (POCPs) for CF3CFCH2 and other commercially significant hydrofluoroolefins have been estimated for the first time. CF3CFCH2 (HFO-1234yf) has a POCP of 7.0 which is less than that for ethane (12.3) and greater than for methane (0.6). Methane and ethane have sufficiently low POCPs that they are usually considered unreactive with respect to ozone formation in urban areas and accordingly are exempt from volatile organic compound (VOC) emission regulations. Estimated POCPs for other hydrofluoroolefins are: CH2CF2, 18.0; CF2CF2, 12.5; CH2CHCF3, 10.7; CF2CFCF3, 5.4; Z-CHFCFCF3, 5.6; E-CHFCFCF3, 7.3; CH2CHCF2CF3, 6.6; and t-CHFCHCF3, 6.4.  相似文献   
135.
Scientific information is not always effectively incorporated into decision-making processes. This phenomenon seems to hold even when the information is aligned with an articulated need, is generated according to sound scientific procedures, and is packaged with end-user preferences in mind. We propose that contextual or cultural differences contribute significantly to the misalignment in communication between those who generate information and those who seek information for improved management of natural resources. The solution is to cultivate shared understanding, which in turn relies on acknowledgment and sharing of diverse values and attitudes. This constitutes a difficult challenge in a culturally diverse environment. Whereas cultural diversity represents wealth in experiences, knowledge and perspectives it can constrain the potential to develop the shared understandings necessary for effective integration of new information. This article illustrates how a lack of shared understanding among participants engaged in a resource-management process can produce and perpetuate divergent views of the world, to the extent that information and knowledge flows are ineffective and scientific information, even when requested, cannot be used effectively. Four themes were distilled from interviews with management and scientific staff of a natural resource–management agency in South Africa. The themes are used to illustrate how divergent views embedded in different cultures can discourage alignment of effort toward a common purpose. The article then presents a sense-making framework to illustrate the potential for developing shared understandings in a culturally diverse world.  相似文献   
136.
ABSTRACT

The momentum achieved for unilateral carbon taxes in seven European countries is examined. Why is it that small countries, despite being vulnerable to forces of international competition, have been able to implement carbon taxes? A review of national experiences does not suggest that the share of fossil fuels in the energy mix defines the room for such taxes, or point to a strong role for traditional left-right ideology. Rather, it is deep-seated patterns of national policy styles with neo-corporatist traits, providing a protective device for the open economies of small countries, which condition the introduction of carbon taxes. The associated routines of decision-making offer coordination mechanisms for proactive macroeconomic policies in which carbon taxation can find a place. Parliamentary democracies with proportional representation, as is common in the smaller countries, provide access to government for political parties that pursue carbon taxation. These in turn sensitise larger political parties to climate concerns, as they benefit from institutionalised practices and routines for problem-solving and consensus-seeking.  相似文献   
137.
Residue materials generated in the metallurgical industry have gained an increasing importance, both from the points of view of energy and material supply. A joint process integration model for the integrated steel plant system is developed and used in this paper. It takes into account both residue materials and energy recirculation for the system. The potential for increased recirculation and the effect on the system from an environmental point of view is presented, and implementations and practical experiences are discussed. The model developed can serve as a benchmark for different steelmaking operations and constitute a basis for the continuous work involved in material, energy, environment or economic analyses for the steel production system.  相似文献   
138.
It is crucial for a steel making production system to operate at the lowest possible production cost, while satisfying stability and reliability conditions. To plan future production strategies, it is therefore important to be able to model the system behaviour when internal and external parameters are changed. In this study the sensitivity and stability of an optimised solution, of an integrated steel plant, have been investigated. The solution’s sensitivity has been analysed taking both internal process changes and external price variations into account, through applying both simulation and optimisation. The analysis also includes both costs and environmental issues such as carbon dioxide and sulphur emissions. Based on the methodology suggested, it is possible to determine the stability of the system solution, including both economic and environmental performance.  相似文献   
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