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21.
H. Oudadesse J. L. Irigaray Y. Barbotteau V. Brun Ph. Moretto 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):458-465
Bioactive glasses are used as coating biomaterials to facilitate anchorage of metallic prostheses implanted into the body. The aim of this work is to study the behavior of gel formed in contact with alloys and BVA and BVH bioactive glasses implanted. Cylinders of metallic implants composed by Ti, Al and V, are coated with bioactive glass. Three sheep were implanted for different time length: 3, 6 and 12 months in the femoral epiphysis. Results obtained with particle induced X-ray emission and scanning electron microscopy show that BVA coating induces a better contact between the metallic implant and bone. On the other hand, BVH coating prevents corrosion from the metallic implant. 相似文献
22.
Ph. MullhauptAuthor Vitae B. SrinivasanAuthor VitaeD. BonvinAuthor Vitae 《Automatica》2002,38(9):1565-1573
Analysis of exclusively kinetic two-link underactuated mechanical systems is undertaken in this paper. It is first shown that such systems are not full-state feedback linearizable around any equilibrium point. Also, the equilibrium points for which the system is small-time locally controllable (STLC) is at most a one-dimensional submanifold. A concept less restrictive than STLC, termed the small-time local output controllability (STLOC) is introduced, the satisfaction of which guarantees that a chosen configuration output can be controlled at its desired value. It is shown that the class of systems considered is STLOC, if the inertial coupling between the input and output is nonzero. Also, in such a case, the system is nonminimum phase. An example section illustrates all the results presented. 相似文献
23.
Ph. A. Passeraub G. Rey-Mennet P. A. Besse H. Lorenz R. S. Popovic 《Sensors and actuators. A, Physical》1997,60(1-3):122-126
A high-sensitivity flat-coil inductive proximity sensor microsystem has been realized and successfully tested. The flat coil, made with CMOS-compatible post processes, is connected to a versatile differential relaxation oscillator electronic interface. In this new and simple interface, the excitation, the signal extraction and amplification are assured by only one operational amplifier. Experimental results on the microsystem confirm that large output frequency variations occur when a metallic target approaches the sensor. 相似文献
24.
Bafleur M. Vidal M. Puig Buxo J. Givelin Ph. Macary V. Sarrabayrouse G. 《Analog Integrated Circuits and Signal Processing》1995,8(3):219-231
To answer to the need of a cost effective smart power technology, an original design methodology that permits implementing latch-up free smart power circuits on a very simple CMOS/DMOS technology is proposed. The basic concept used to this purpose is letting float the wells of the MOS transistors most susceptible to initiate latch-up. The efficiency of the design methodology is experimentally shown. 相似文献
25.
Eric P. Kvam Ph.D. Srikanth B. Samavedam B.Tech. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(3):47-51
The Ge-Si on Si epilayer system, besides being an interesting technological system in its own right, is a superb model for strained-layer studies. The point defect and symmetry defect structures associated with compound semiconductors can be avoided, allowing a focus on the mechanics of the system. Dislocation sources, glide behavior, and performance effects have been examined for strained-layer systems. Surprises have appeared along the way, but these materials are now becoming characterized well enough for industrial device applications. 相似文献
26.
Xuezhi Zhang Ph.D. Andrejs Atrens Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(1):48-50
A boundary problem arising from rapid solidification with changing conditions at the moving boundary for the classical Stefan problem was solved by combining the heat transfer with crystallization kinetics using a front-tracking finite-difference scheme. At each time step, the conditions at the moving boundary were determined by an iterative process. 相似文献
27.
Y. C. Lee Ph.D. Nagesh Basavanhally Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(6):46-50
In addition to providing electrical connections, solder is useful in the formation of passive, precision alignments for optoelectronic packaging. Different designs have demonstrated micrometer-level alignment accuracies, and the aligned structures are becoming more and more complex. Solder engineering has been successfully introduced into the field of optoelectronics, and it is expected to be applied to many other areas demanding low-cost, precision alignments. 相似文献
28.
29.
M. T. Collins Ph.D. E. J. McConaghy B. Chem. Eng. B.Sc. R. F. Stauffer B.Sc. G. J. Desroches B.Sc. B. D. Krysa B.Sc. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(4):51-58
The first commercial application of the Sherritt two-stage zinc pressure leach process commenced operation at the Hudson Bay Mining and Smelting Company metallurgical complex in Flin Flon, Manitoba (Canada), on July 2, 1993. The start-up was relatively smooth, and full design rate for the plant was achieved by September 12, 1993. Since that time, zinc extraction in the zinc pressure leach plant has consistently been in excess of 98%, and production has continued to exceed expectations. The successful operation of the Hudson Bay plant represents a significant advancement of zinc processing technology, especially with respect to meeting the environmental challenge faced by zinc plants today. 相似文献
30.
Ching-Hwa Lee Ph.D. Tei-Chih Cheau Ph.D. Sang-Teh Chen B.S. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(5):40-42
The metals recovered from automotive scrap can provide important resources for industrial development. Thus, the construction of a new plant was undertaken to help recycle valuable metals from nonferrous auto scrap in Taiwan. The main purpose of this project was to establish an automated heavy medium separation technique to cull aluminum from automotive scrap, and thus to replace the labor-intensive hand-picking process. The design capacity of the resulting heavy medium separation plant is two tonnes per hour and the completion of this plant will reduce hand-picking labor by 80%. 相似文献