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991.
J. R. He G. C. I. Lin 《The International Journal of Advanced Manufacturing Technology》1992,7(4):210-217
A computerised trace method has been developed for determining the relationships of assembly requirements with design dimensions
and tolerances of the components in an assembly, and the relationships of design specifications and machining allowance requirements
with manufactured dimensions and tolerances of the component in a process plan. This method traces from the proposed components
or planned operations only the dimensions and tolerances that affect the given requirement, and therefore the equations for
design or for manufacture can be established simultaneously and accurately. Hence it is possible to establish constraints
for the optimisation of dimensions and tolerances for design or for manufacture. 相似文献
992.
993.
The brittle-ductile transition temperature in the solidification range depends on the composition of the phase which solidifies as the last one. The paper presents a thermochemical study of Fe-Mn-C-P system, determining the conditions of crystallisation of carbides, phosphides and the pseudo-ternary eutectic ML-M3C-M3P. Manganese raises the phosphorus concentration in eutectic. The eutectic temperature attains its maximum at about 6% of Mn. Then the brittle-ductile transition temperature is about 30 K higher than in ternary Fe-C-P alloy. A further raise is possible when the alloy is modified by an element forming stable, solide carbide, for ex. titanium. The results of theoretical analysis were verified by experimental work. The influence of titanium on the inclusions appearing in the vicinity of hot cracks of Hadfield cast steel has been studied. 相似文献
994.
I. S. Sheinin I. S. Kal'tseva 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(3):168-175
Translated from Gidrotehnicheskoe Stroitel'stvo, No. 3, pp. 27–31, March, 1992. 相似文献
995.
L. A. Kryachko V. N. Paderno O. I. Kovalenko 《Powder Metallurgy and Metal Ceramics》1992,31(6):510-518
Translated from Poroshkovaya Metallurgiya, No. 6(354), pp. 58–69, June, 1992. 相似文献
996.
997.
Embabi S.H.K. Bellaouar A. Elmasry M.I. Hadaway R.A. 《Solid-State Circuits, IEEE Journal of》1991,26(2):150-153
Circuit techniques are presented for increasing the voltage swing of BiCMOS buffers through active charging and discharging using complementary bipolar drivers. These BiCMOS circuits offer near rail-to-rail output voltage swing, higher noise margins, and higher speed of operation at scaled-down power supply voltages. The circuits are simulated and compared to BiCMOS and CMOS buffers. The comparison shows that the conventional BiCMOS and the complementary BiCMOS buffers are efficient for power supply voltages greater than 3V and that if the power supply voltage is scaled down (<3 V) and the load capacitance is large (>1 pF), the complementary BiCMOS buffers would be the most suitable choice. They provide high speed and low delay to load sensitivity and high noise margins. The first implementation is favorable near a 2.5-V power supply for its smaller area 相似文献
998.
The influence of nicotinamide and oxythiamine on the activity of NADPH-producing dehydrogenases of glucoso-6-phosphate, 6-phosphogluconate, malate, isocitrate, as well as concentration and synthesis rate of fatty acids in fatty tissue were studied in experiments on mice with genetically conditioned non-insulin-dependent diabetes and hyperinsulinemia. It has been established that in these diseases the synthesis of fatty acids and their inclusion into lipids are activated without increasing the above enzymes activity. It is shown that nicotinamide and oxythiamine inhibit inclusion of C from glucose into free fatty acids, antivitamin intensifies lipolysis in the fatty tissue of the diseased animals. 相似文献
999.
Ya. A. Kamenchuk S. I. Pisareva L. N. Andreeva F. G. Unger 《Chemistry and Technology of Fuels and Oils》2006,42(1):39-42
Precipitation of sediment caused by external factors — temperature and solvent — is due to the spin nature of the contaminants
formed during use of the oil. These paramagnetic contaminants also lead to aging of oils. Their total elimination restores
the properties of used oil to the level of the base oil, but requires sufficient energy effects.
__________
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 1, pp. 29–31, January–February, 2006. 相似文献
1000.
A. A. Vaipolin Yu. A. Nikolaev V. Yu. Rud’ Yu. V. Rud’ E. I. Terukov 《Semiconductors》2003,37(4):414-416
Photosensitive structures of surface-barrier and homojunction types have been fabricated for the first time on the basis of ZnIn2Se4 single crystals. The spectral dependence of the quantum efficiency of photoconversion has been studied and discussed. It is concluded that the structures are promising for commercial applications. 相似文献