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131.
M. R. JOYCE K. K. LEE S. SYNGELLAKIS P. A. S. REED 《Fatigue & Fracture of Engineering Materials & Structures》2004,27(11):1025-1036
Complex multi‐phase Al–Sn–Si alloys are commonly employed in the manufacture of small automotive plain bearings. The fundamental fatigue initiation behaviour of this class of alloys is currently not well understood. A range of analytical techniques were applied to investigate preferential initiation site location and to attempt to identify critical microstructural features. It was apparent from experimental studies that points of fatigue crack initiation are associated with the Si secondary phase. Using tessellation approaches and subsequently both adaptive numerical modelling and micro‐scale finite element modelling allowed the identification of features affecting the probability that a given Si phase would initiate a fatigue crack. 相似文献
132.
To improve the safety of plant start-up operation, a safety evaluation system has been developed. As a key component in an operational design support system, the evaluation system examines any potential hazards during start-up operation simulation. The evaluation system is integrated into an operational design methodology which designs operable processes by proposing alternatives, examining process safety and operability, and modifying operating procedures or plant structures. Issues for both methodology and implementation of a G2-based expert system are discussed. Finally, the system is applied to an industrial hydrodesulphurization process. 相似文献
133.
Iron dialyzability (ID) from three Cruciferae (broccoli, kale and cabbage) was determined by an in vitro digestion method. The effect of added Crucifers on the ID of extrinsic nonheme iron as well as effects of heating were studied. Uncooked Crucifers contained iron of moderate ID (7–9%); cooking resulted in substantial ID increase (200%). Cooked Crucifers increased extrinsic ID three- to fourfold. Time and temperature relationships for the increase suggested that organic acids released after partial cell wall degradation combined with protein denaturation and iron solubilization from fiber were major reasons for differences between raw and cooked vegetables. Cruciferous vegetables can contribute to improved iron nutrition. 相似文献
134.
Reference materials for quantitative determination of regulated heavy metals, such as Pb and Cd in electronic components, were designed and investigated in terms of stability and homogeneity. Reference materials with two concentration levels of heavy metals were prepared by spiking Pb and Cd compounds to epoxy molding compounds made by mixing silica powders and epoxy resin. The concentration changes of the reference materials during stability test for 1 a were not observed. In the homogeneity assessment, the as-prepared reference materials were studied by using three different analytical tools, inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray fluoroescence spectrometry (XRF) and laser ablation ICP mass. The results show different homogeneities by the characteristics of analytical tools and the materials. 相似文献
135.
Kil-Sung LEE Hyeon-Kyeong SEO Yong-June YANG Woo-Chae HWANG Kwang-Hee IM In-Young YANG 《中国有色金属学会会刊》2011,(Z1):135-140
The recent trend of vehicle design aims at crash safety and environmentally-friendly aspect. For the crash safety aspect, the energy absorbing members should absorb collision energy sufficiently but for the environmentally-friendly aspect, the vehicle structure must be light weight in order to improve the fuel efficiency and reduce the tail gas emission. Therefore, the light weight of vehicle must be achieved in a securing safety status of crash. An aluminum or carbon fiber reinforced plastics (CFRP) is rep... 相似文献
136.
Min Ku LEE Jung Gu LEE Jong Keuk LEE Sung Mo HONG Sang Hoon LEE Jin Ju PARK Jae Woo KIM Chang Kyu RHEE 《中国有色金属学会会刊》2011,(Z1):7-11
The microstructures of the brazed joints for commercially pure Ti and stainless steel were investigated by the applications of various filler alloys including Ag-, Ti-, Zr- and Ni-based alloys. Generally, the dissimilar joints between Ti and stainless steel were dominated by the Ti-based intermetallic compounds (IMCs), e.g. (Ti, Zr)2(Fe, Ni), TiFe, TiCu, and Ti2(Fe, Ni), due to a significant dissolution of Ti from the base metal. The (Fe-Cr) σ phase was also observed near the stainless steel due to a segregation of Cr into the interface region. This research demonstrates empirically that the brittleness of the Ti and stainless steel joint can not be avoided only by applying single braze alloy or single insert metal, and thus an introduction of additional suitable interlayer between the filler alloy and the base metal is necessary to prevent the brittleness of the joint. 相似文献
137.
Multicast technology application has been widely utilized in broadband internet. Source authentication is one of the most needs for many multicast applications transferring real-time information such as stream video and online news. Because multicast current services provided to the group members are changed dynamically, data transferring by a group member is not used by the recipient. In order to verify the identity of the sender who sent the packet and to make sure that the data have not been tampered, an optimized source authentication scheme has been proposed to transfer the authentication information not to the next-door packet. The proposed method for multiple packets authenticates the source with a limited number of electronic signatures. The proposed method can reduce overhead compared to the method by adding a digital signature for every packet. In addition, by sending the generated electronic signature to the first packet and the last packet, it prevents the loss of consecutive packets, as well as a source authentication can be provided in real-time services. 相似文献
138.
Tenderization of Meat with Ginger Rhizome Protease 总被引:5,自引:0,他引:5
Beef steaks and sliced beef marinated with different levels of crude ginger extract were evaluated for the tenderness and structural changes. A significant (P<0.05) enhancement of tenderness with increasing amounts of ginger extract was observed at low levels of extract (0, 0.05, 0.1, and 0.2 mL/6.5 cm2 for the steaks; 0, 0.25, 0.5, and 1 mL/lOOg for the sliced beef), whereas further improvement of tenderness at more than 0.2 mL/6.5 cm2 or 1 mL/lOOg was minimal. Electron microscopy of the treated beef revealed the preferential degradation of thin filaments in the I-bands, resulting in extensive fragmentation of myofibrils. Thus, ginger rhizome protease is an effective meat tenderizer and the tenderization is achieved through preferential degradation of thin filaments. 相似文献
139.
SEONG- JIN CHOI SAHN NAHM JAE-DONG BYUN KYUNG-SOO SUH HWACK JOO LEE HYUN RYU 《Journal of Materials Science Letters》1997,16(10):785-787
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
140.
Phase transfer experiments were performed, involving contact between an aqueous 1:1 solution of α-lactalbumin and β-lactoglobulin and an AOT-in-isooctane reversed micellar phase. The resulting extraction and separation of the two proteins were analyzed as functions of pH, ionic strength and total protein concentration using SDS-PAGE, and compared with extractions from pure solutions. At low protein concentrations, the extent of reversed micellar solubilization of the two pure proteins predicted well the extraction from mixtures. However, at higher protein concentrations β-lactoglobulin appeared to be excluded from the micellar droplets. Because of the significantly different partitioning behavior of the two proteins, reversed micellar extraction from an initially equal weight mixture led to an effective separation of the proteins. 相似文献