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531.
Witold Pawlus Hamid Reza Karimi Kjell Gunnar Robbersmyr 《Journal of Mechanical Science and Technology》2011,25(7):1737-1747
In this paper, we propose a method of modeling for vehicle crash systems based on viscous and elastic properties of the materials.
This paper covers an influence of different arrangement of spring and damper on the models’ response. Differences in simulating
vehicle-torigid barrier collision and vehicle-to-pole collision are explained. Comparison of the models obtained from wideband
(unfiltered) acceleration and filtered acceleration is done. At the end we propose a model which is suitable for localized
collisions simulation. 相似文献
532.
Henselmans Inge; Helgeson Vicki S.; Seltman Howard; de Vries Jakob; Sanderman Robbert; Ranchor Adelita V. 《Canadian Metallurgical Quarterly》2010,29(2):160
Objective: In this article, we aim to (a) identify distinct trajectories of psychological distress in the first year after a breast cancer diagnosis in women treated with adjuvant therapy and (b) explore possible predictors of these trajectories, that is, demographic, medical, and personal characteristics. Method: The 171 patients were assessed after diagnosis, after surgery, after adjuvant treatment, in the reentry phase, and in the (short-term) survivorship phase (2 and 6 months after the end of treatment, respectively). Main Outcome Measure: Psychological distress was assessed with the 12-item General Health Questionnaire. Results: There were four trajectories of distress: a group that experienced no distress (36.3%), a group that experienced distress only in the active treatment phase (33.3%), a group that experienced distress in the reentry and survivorship phase (15.2%), and a group that experienced chronic distress (15.2%). Personality and physical complaints resulting from adjuvant treatment could distinguish the distress trajectories. Mastery was the only unique predictor. Conclusion: Most patients were not distressed in response to breast cancer or only temporarily so. Yet, a minority of patients became or remained distressed after the end of treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
533.
534.
Eva Veiseth-Kent Kjell I. Hildrum Ragni Ofstad Mia B. Rørå Per Lea Marit Rødbotten 《Food chemistry》2010
The main objective of this study was to compare the effects of three different processing treatments on sensory attributes and instrumental quality measurements of raw Atlantic salmon (Salmo salar) fillets. Salmon was either pre-rigor filleted and restricted or allowed to contract (Vacuum-PRE and Contracted-PRE, respectively) or post-rigor filleted (POST). Sensory evaluation (appearance, flavour, texture) and instrumental quality measurements (colour, texture, fat, astaxanthin, liquid holding capacity) were performed at 5–7 days postmortem. Sensory evaluation revealed that Vacuum-PRE fillets had less desirable quality attributes than the other treatment groups, with higher scores for tenderness and whiteness and lower scores for hardness and colour intensity. The observed changes in fillet height between the treatment groups indicated that the immediate vacuum packaging of the Vacuum-PRE fillets had limited their contraction during rigor mortis development, resulting in the negative effects observed on quality. This implicates that the well-known positive effects of pre-rigor filleting regarding colour and texture can be reduced or even abolished if the fillets are restricted from contraction during rigor mortis development. 相似文献
535.
Information and communication technologies (ICTs) increasingly permeate everyday life in industrialized societies. The aim of this paper is to explore ICT-related transformations of everyday practices and discuss the implications, particularly for residential electricity consumption. The present socio-technical changes are seen in a historical perspective, and it is argued that the integration of ICT into everyday practices can be seen as a new round of household electrification, comparable to earlier rounds that also led to higher electricity consumption. A case study carried out in Denmark in 2007–2008 explores the present changes in everyday life. Based on qualitative interviews, the study focuses on people's ways of integrating ICTs into their everyday practices, on any significant changes in these practices, and on the influence of the changed practices on electricity consumption. The paper concludes with a discussion on the implications for energy policy. 相似文献
536.
贝尔维蒂宫位于奥地利首都的中心,它是巴洛克式建筑中的一颗耀眼的宝石。Marble大厅是一座装饰着高大镜子的巨大房间,天花板上有大量壁画和闪闪发光的吊灯。 相似文献
537.
Volodymyr Pavlyuk Grygoriy Dmytriv Ihor Chumak Oliver Gutfleisch Inge Lindemann Helmut Ehrenberg 《International Journal of Hydrogen Energy》2013
The existence of Li-rich super-lightweight intermetallics in the Li–Mg–Si ternary system has attracted attention for high capacity hydrogen storage materials. The hydrogenation properties of the alloys were studied by thermogravimetric analysis, differential scanning calorimetry in H2 atmosphere and X-ray diffraction. The Li-rich alloy absorbs the highest amount of hydrogen (8.8% w/w for Li70Mg10Si20), while the Mg-rich alloy (Li30Mg40Si30) absorbs 6.0% w/w H2 and shows the first experimental evidence for LiMgH3 formation with LiNbO3-type structure during hydrogenation. 相似文献
538.
The most important contributors to the world's total oil production are the giant oil fields. Using a comprehensive database of giant oil field production, the average decline rates of the world's giant oil fields are estimated. Separating subclasses was necessary, since there are large differences between land and offshore fields, as well as between non-OPEC and OPEC fields. The evolution of decline rates over past decades includes the impact of new technologies and production techniques and clearly shows that the average decline rate for individual giant fields is increasing with time. These factors have significant implications for the future, since the most important world oil production base – giant fields – will decline more rapidly in the future, according to our findings. Our conclusion is that the world faces an increasing oil supply challenge, as the decline in existing production is not only high now but will be increasing in the future. 相似文献
539.
Manuel Weirich Jonas GurauskisVanesa Gil Kjell WiikMari-Ann Einarsrud 《International Journal of Hydrogen Energy》2012
Lanthanum tungstate materials have been reported to show exceptional mixed proton and electron conducting behaviour at elevated temperatures and making them attractive for dense hydrogen gas separation membranes. In this work preparation of planar asymmetric lanthanum tungstate membranes was addressed. For this purpose carbon black and rice starch pore formers were evaluated for optimum substrate gas permeability. It was found that carbon black pore former results in higher level of effective porosity. Stabilization of fine lanthanum tungstate powder in ethanol based solvent media was carried out to find out optimum surfactant quantity for tape casting slurry. By combining lanthanum tungstate tapes with and without pore former defect free asymmetric membranes were produced by conventional sintering. 相似文献
540.
Sebastian Beggel Inge Werner Juergen P. Geist 《The Science of the total environment》2010,408(16):3169-170
Toxic effect concentrations of insecticides are generally determined using the technical grade or pure active ingredient. Commercial insecticide formulations, however, contain a significant proportion (> 90%) of so-called inert ingredients, which may alter the toxicity of the active ingredient(s). This study compares the sublethal toxicity of two insecticides, the pyrethroid bifenthrin, and the phenylpyrazole fipronil, to their commercial formulations, Talstar® and Termidor®. Both insecticides are used for landscape treatment and structural pest control, and can be transported into surface water bodies via stormwater and irrigation runoff. We used larval fathead minnow (Pimephales promelas), to determine effects on growth and swimming performance after short-term (24 h) exposure to sublethal concentrations of pure insecticides and the respective formulations. Significantly enhanced 7 d growth was observed at 10% of the 24 h LC10 (53 μg L−1) fipronil. Swimming performance was significantly impaired at 20% of the 24 h LC10 (0.14 μg L−1) of bifenthrin and 10% of the 24 h LC10 of Talstar® (0.03 μg L−1). Fipronil and Termidor® led to a significant impairment of swimming performance at 142 μg L−1 and 148 μg L−1 respectively, with more pronounced effects for the formulation. Our data shows that based on dissolved concentrations both formulations were more toxic than the pure active ingredients, suggesting that increased toxicity due to inert ingredients should be considered in risk assessments and regulation of insecticides. 相似文献