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981.
The Goal Orientation Scale (GOS) developed by VandeWalle, Cron and Slocum (2001) is used to assess learners’ goal orientation style. However, this scale is in English, limiting its applications with francophone populations. This study documents the psychometric properties of a French version of the GOS. The instrument was translated and verified by expert translators then administered to 219 French-speaking students enrolled in two Quebec Universities. The subjects also responded to a measure of fear of negative evaluation, general self efficacy and locus of control. Analyses of the factor structure, internal consistency, temporal stability and the pattern of correlations with external variables indicates that this French version converges with the original English instrument. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
982.
This paper summarizes results on the use of quantitative microscopy in relating microstructural features to the friability of a model abrasive material, Al2O3-ZrO2. Quantitative stereology was used to characterize the geometric aspects of the microstructure of fused Al2O3-ZrO2 abrasives and to relate these to friability. The microstructure was controlled by varying processing parameters. The quench rate of the material from the melt was found to exhibit the most control over the microstructure. The friability was measured using three methods: the ball mill test, a DeBeers Friatester and a microfriability test developed for this study. Friability was found to be controlled by the geometric aspects of microstructure. The microstructural parameter which appeared to exert the largest influence over friability was the scale factor glα. A fracture mechanics approach was employed to explain the observed increase in strength and toughness in Al2O3-ZrO2 materials. 相似文献
983.
基于机构动力学-控制系统协同仿真与优化的凸轮廓线优化设计 总被引:2,自引:0,他引:2
为了降低高速吹瓶机中凸轮机构带动的模具合模时出现的接触力,提出了基于机构动力学-控制系统协同仿真和优化的凸轮廓线优化设计方法.首先,建立吹瓶机模具运动控制系统模型,目标函数是在最大接触力约束下运动时间最短.其次,根据赫兹接触理论中接触力与变形量的关系,引入位移状态变量,将高速无冲击凸轮廓线设计问题转化为位移无超调的最速... 相似文献
984.
Robert F. DeJaco Matheus Dorneles de Mello Huong Giang T. Nguyen Mi Young Jeon Roger D. van Zee Michael Tsapatsis Joern Ilja Siepmann 《American Institute of Chemical Engineers》2020,66(4):e16868
In this work, batch-adsorption experiments and molecular simulations are employed to probe the adsorption of binary mixtures containing ethanol or a linear alkane-1,n-diol solvated in water or ethanol onto silicalite-1. Since the batch-adsorption experiments require an additional relationship to determine the amount of solute (and solvent) adsorbed, as only the bulk liquid reservoir can be probed directly, molecular simulations are used to provide a relationship between solute and solvent adsorption for input to the experimental bulk measurements. The combination of bulk experimental measurements and simulated solute–solvent relationship yields solvent and solute loadings that are self-consistent with simulation alone, and allow for an assessment of the various assumptions made in the literature. At low solution concentrations, the solute loading calculated is independent of the assumption made. At high concentrations, a negligent choice of assumption can lead to systematic overestimation or underestimation of calculated solute loading. 相似文献
985.
Robert Creutznacher Eric Schulze Georg Wallmann Prof. Dr. Thomas Peters Dr. Matthias Stein Dr. Alvaro Mallagaray 《Chembiochem : a European journal of chemical biology》2020,21(7):1007-1021
Bile acids have been reported as important cofactors promoting human and murine norovirus (NoV) infections in cell culture. The underlying mechanisms are not resolved. Through the use of chemical shift perturbation (CSP) NMR experiments, we identified a low-affinity bile acid binding site of a human GII.4 NoV strain. Long-timescale MD simulations reveal the formation of a ligand-accessible binding pocket of flexible shape, allowing the formation of stable viral coat protein–bile acid complexes in agreement with experimental CSP data. CSP NMR experiments also show that this mode of bile acid binding has a minor influence on the binding of histo-blood group antigens and vice versa. STD NMR experiments probing the binding of bile acids to virus-like particles of seven different strains suggest that low-affinity bile acid binding is a common feature of human NoV and should therefore be important for understanding the role of bile acids as cofactors in NoV infection. 相似文献
986.
A hybrid sorbent material for removal of hydrogen sulfide from air was developed. The material is based on activated carbon and iron compounds obtained from waste iron(II) sulfate(VI) heptahydrate. The iron salt is deposited on the carbonaceous support and subjected to oxidation (Fe2+ to Fe3+) using atmospheric oxygen under alkaline conditions. An effect of H2O2 addition to the process on the composition of the resultant material was also examined. X-ray diffraction (XRD) analyses confirmed easy conversion of waste FeSO4·7H2O to iron oxides Fe3O4 and FeOOH. The activated carbon supporting iron oxides revealed a higher efficiency in H2S elimination from air compared to the commercial activated carbon, without any modification. 相似文献
987.
Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
988.
Declerck Nathalie; Machius Mischa; Joyet Philippe; Wiegand Georg; Huber Robert; Gaillardin Claude 《Protein engineering, design & selection : PEDS》2003,16(4):287-293
Bacillus licheniformis 相似文献
989.
Jernej Drofenik Robert Dominko Mogens Mogensen Stane Pejovnik 《Electrochimica acta》2003,48(7):883-889
Four types of cellulose, in particular carboxy methyl cellulose (CMC), are tested as potential binding materials in graphitic anodes for lithium ion batteries. It is shown that a minimum content of a cellulose which gives acceptable anode properties (reversible capacity>300 mA h g−1 during the first 10 cycles, irreversible loss<20%) is about 2 wt.%, which is less than in the case of conventional polymeric binders (5-10 wt.%). Kinetics of insertion-deinsertion and passivation processes seem not to be affected by the presence of cellulose. Explanation for the electrode failure at cellulose contents lower than 1 wt.% is given based on X-ray diffraction and microscopy investigations. Finally, the structure (distribution) of cellulose in the composite anode material is discussed and (indirectly) checked with a series of experiments. Most results are compared with the corresponding results obtained either with gelatin or conventional polymeric binders or both. 相似文献
990.
Staphylococcus epidermidis is a bacterium that is part of the human microbiota. It is most abundant on the skin, in the respiratory system and in the human digestive tract. Also, Staphylococcus aureus contributes to human infections and has a high mortality rate. Both of these bacterial species produce biofilm, a pathogenic factor increasing their resistance to antibiotics. For this reason, we are looking for new substances that can neutralize bacterial cells. One of the best-known substances with such effects are silver nanoparticles. They exhibited antibacterial and antibiofilm formation activity that depended on their size, shape and the concentration used. In this review, we presented the data related to the use of silver nanoparticles in counteracting bacterial growth and biofilm formation published in scientific papers between 2017 and 2021. Based on the review of experimental results, the properties of nanoparticles prompt the expansion of research on their activity. 相似文献