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91.
J. Hardell A. Yousfi M. Lund L. Pelcastre B. Prakash 《Tribology - Materials, Surfaces & Interfaces》2014,8(2):90-97
AbstractAbrasive wear in industrial applications such as mining, materials handling and agricultural machinery constitutes a large part of the total wear. Hardened high strength boron steels are known for their good wear resistance and mechanical properties, but available results in the open literature are scarce. This work aims at investigating how different quenching techniques affect the two-body abrasive wear resistance of hardened high strength boron steels. Furthermore, the wear as a function of depth in thicker hardened high strength boron steel plates has also been studied. The material characterisation has been carried out using microhardness, SEM/energy dispersive spectroscopy and three-dimensional optical surface profilometry. The results have shown that water quenched and tool quenched high strength boron steel had similar wear resistance. The main wear mechanisms appear to be microcutting combined with microfatigue. Workhardening during the abrasion process has been found to affect the abrasive wear. 相似文献
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Nam Seung-Hee Kim Young-Min Walsh Marie K. Yim Sun-Hee Eun Jong-Bang 《Food science and biotechnology》2016,25(1):31-39
This study was performed to characterize pear protease proteolytic activity and investigate the use of pear protease as a meat tenderizer. Pear protease was purified and stabilized by 5% dextrin during lyophilization (dry) or concentration (liquid). Pear protease was further characterized with respect to pH, thermodynamics, and enzyme kinetics. Pear protease was stable at a pH range of 5-8 with an optimum pH of 6.5. From Arrhenius plots, liquid protease showed higher temperature dependency (23.49 kJ/mol) than dry protease (18.62 kJ/mol) due to its higher activation energy. The kcat/Km, catalytic efficiency of enzyme, was similar with 2.9 and 2.7 µM/min with dry and liquid proteases. Pear protease was evaluated for its proteolytic activities with casein and beef myofibrillar proteins by individually and combination with fig and kiwifruit proteases. These result indicated that pear and kiwifruit proteases could be complementary to be a desirable product for meat tenderization. 相似文献
94.
A highly nonlinear increase in electrical conductivity and concomitant photoemission occurs not only during “flash sintering” but also in presintered, dense specimens. We report results from experiments with dense specimens that show a strong correspondence between the intensity of photoemission and electrical conductivity of specimens under a variety of conditions of the electrical parameters. It is proposed that both properties are related to the concentration of electron–hole pairs generated in such experiments. 相似文献
95.
John McDonald Rosalee Wolfe Jerry Schnepp Julie Hochgesang Diana Gorman Jamrozik Marie Stumbo Larwan Berke Melissa Bialek Farah Thomas 《Universal Access in the Information Society》2016,15(4):551-566
Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays. 相似文献
96.
Marie Hurtgen Antoine Debuigne Didier Gigmes Christine Jérôme Christophe Detrembleur 《Polymer》2012,53(20):4353-4358
The grafting mechanism of poly(vinyl acetate) macroradicals prepared by cobalt-mediated radical polymerization onto C60 is investigated. The experimental conditions directly impact the nature and stability of the PVAc/C60 adducts. In the presence of residual initiating radicals that can compete with PVAc° macroradicals for addition onto C60, mixtures of PVAc/C60 adducts having between one and eight polymer chains per C60 are formed. PVAc/C60 adducts prepared with low [PVAc]:[C60] ratios may contain weak C60–C60 bonds that further dissociate and account for the instability of the products. The formation of such dimers can be lessened by increasing the temperature from 30 °C to 100 °C. The temperature increase also allows a complete dissociation of the PVAc-Co dormant species into PVAc° macroradicals and an almost quantitative grafting of eight PVAc chains onto C60, leading to well-defined C60(PVAc)8 octa-adducts. These results might shed new light on the grafting onto C60 of macroradicals prepared by other CRP techniques. 相似文献
97.
What Business Owners Expect From a Crisis Manager? A Competency Model: Survey Results From Czech Businesses 下载免费PDF全文
This competency model of a crisis manager has been developed based on cooperation with managers and experts in the field of crisis management. The brainwriting method was used to generate an overview of the competencies expected of a crisis manager. Using a mind map three basic groups of competencies were developed. The participants used Saaty's method to determine the significance of individual competencies. The different attributes of individual competencies according to the level of their development were established. Finally all individual competencies were assigned a target value which indicates the expected level of competence for the position of a crisis manager. The model of competencies is a practical tool for the establishment of crisis management system in a company. 相似文献
98.
Tristan Kolb Christian Neuber Marie Krysak Christopher K. Ober Hans‐Werner Schmidt 《Advanced functional materials》2012,22(18):3865-3873
Each film preparation technique affects the physical properties of the resulting coating and thus defines its applicability in modern device construction. In this context solvent based spin coated and solvent‐free physical vapor deposited molecular glass photoresist films are systematically investigated for their dissolution behavior, sensitivity, and overall lithographic performance. These investigations demonstrate that the solvent‐free physical vapor deposition leads to a marked increase in sensitivity. This could be explained by the individual molecule by molecule deposition step producing a more homogeneous distribution of the multicomponent resist system, especially the photoacid generator. In addition, this assumption is supported by former published simulations focusing on aggregate formation within thin films. This work demonstrates that the lithographic sensitivity of multicomponent resist system is an intrinsic parameter to investigate molecular material distribution and indicates that the applied film preparation technique is crucial for the corresponding performance and applicability. 相似文献
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