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91.
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
92.
In a recent study by Gurnani (1983), ‘Economic analysis of inventory systems’, three main conclusions were presented. (1) The inventory models analysed in his paper demonstrate that the inventory policy derived from the discounted (PW) coat differs substantially from that given by the traditional undiscounted inventory analysis. (2) The difference between the two depends upon the discounting rate. The discounting causes the optimum order quantity and correspondingly the period length to vary monotonically with the discounting rate. (3) However, it is not influenced by the inventory system planning horizon. This paper first examines each conclusion and demonstrates why his conclusions are either unfounded or irrelevant to his analysis. Next, some crucial derivational errors in his exposition are demonstrated via corrected formulations. Finally, a net present value maximizing framework that is consistent with modern theory of financial analysis, is suggested for the economic analysis of inventory systems. 相似文献
93.
EXPERIMENTAL AND NUMERICAL STUDY FOR HYDRODYNAMIC CHARACTERISTICS OF AN OSCILLATING HYDROFOIL 总被引:1,自引:1,他引:0
The present article reports the experimental Particle Image Velocimetry (PIV) investigation and the corresponding numerical simulation results about the water flow over the oscillating hydrofoil and its unsteady dynamic characters. The experimental study focuses on the effect of mean angles of attack. The comparison between the PIV results and numerical prediction about the flow field using Fluent well demonstrates the capability of CFD on the simulation of the water flow around the pitching hydrofoil. The numerical results indicate that the forced oscillating frequencies have evident effects on the flow separation and vortex shedding. The simulations about the hydrodynamic drag and lift coefficients were also performed. 相似文献
94.
Electrophoretic patterns of fresh beef, pork, chicken, and turkey sarcoplasmic proteins were studied using thin layer agarose gel electro-phoresis. Creatine kinase isozyme MM and myoglobin bands were used to identify the species. Binary mixtures (5/95, 25175, 50150, 751 25, 9515, % by weight of each species) were also examined by their electrophoretic and densitometric patterns. Electrophoretic patterns remained stable at elevated pH (7.5), but were affected by low pH (4.7). The relative ratios of the bands which characterized each species changed in proportion to the species content in each binary mixture. These ratios make it possible to predict the approximate fraction of each species present in such mixtures. 相似文献
95.
Equivalent concentrations of polydextrose and sucrose had similar effects on phase transitions of wheat starch-water systems. Onset and peak gelatinization temperatures were increased similarly with the two solutes. This was true with varied water:starch ratios, varied concentrations of solute, and for batters prepared with the two solutes. Acesulfame K, cyclamate, and saccharin at low levels, as might be used in food products, had little effect on phase transitions of starch-water-solute systems. 相似文献
96.
Heat penetration experiments were carried out in a hot water bath with small blocks of a solid polycarbonate material cut into various shapes (cylinder, cube and oval) to obtain heat penetration factors for each shape. These factors, along with characteristic dimensions from the odd shapes were then used in the finite cylinder heat transfer model to predict accurately the temperature at the center of each block in response to measured dynamic bath temperatures. Results showed sufficiently good agreement between predicted and measured center temperature profiles to justify use of the finite cylinder model for rapid evaluation of process deviations in thermal processing of foods in odd-shaped containers. 相似文献
97.
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
98.
SA-KYUN RHA WON-JUN LEE SEUNG-YUN LEE DONG-WON KIM CHONG-OOK PARK 《Journal of Materials Science: Materials in Electronics》1997,8(4):217-221
Copper films having thickness 600 nm were prepared on TiN using chemical vapour deposition (CVD). The deposited films were
annealed at various temperatures (350–550°C) in Ar and H2(10%)-Ar ambients. The changes in the grain size of the films upon annealing were investigated. Annealing in an H2(10%)-Ar ambient produced normal grain growth; annealing in an Ar ambient caused grain growth to stop at 550°C. The grain
size followed a monomodal distribution and the mean size increased in proportion to the square root of the annealing time,
indicating the curvature of the grain is the main driving force for grain growth. Upon annealing at 450°C for 30 min in an
H2(10%)-Ar ambient, the average grain size of the film increased from 122 nm to 219 nm, and the resistivity decreased from 2.35
μΩ cm to 2.12 μΩ cm at a film thickness of 600 nm.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
99.
An agile manufacturing workcell design 总被引:1,自引:0,他引:1
QUINN ROGER D. CAUSEY GREG C. MERAT FRANK L. SARGENT DAVID M. BARENDT NICK A. NEWMAN WYATT S. VELASCO JR VIRGILIO B. PODGURSKI ANDY JO JU-YEON STERLING LEON S. KIM YOOHWAN 《IIE Transactions》1997,29(10):901-909
This paper introduces a design for agile manufacturing worked Is intended for light mechanical assembly of products made from similar components (i.e., parts families). We define agile manufacturing as the ability to accomplish rapid changeover from the assembly of one product to the assembly of a different product. Rapid hardware changeover is made possible through the use of robots, flexible part feeders, modular grippers, and modular assembly hardware. The division of assembly, feeding, and unloading tasks between multiple robots is examined with prioritization based upon assembly time. Rapid software changeover will be facilitated by the use of a real-time, object-oriented software environment utilizing graphical simulations for off-line software development. An innovative dual VMEbus controller architecture permits an open software environment while accommodating the closed nature of most commercial robot controllers. These agile features permit new products to be introduced with minimal downtime and system reconfiguration. 相似文献
100.