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91.
Teplenko Marina A. Podchernyaeva Irina A. Panasyuk Alla D. 《Powder Metallurgy and Metal Ceramics》2002,41(3-4):154-161
We have studied the process of electrospark alloying of titanium alloy VT6 and steels with a composite material based on AlN ZrB2 with ZrSi2 additive. We have established that Al2SiO5 and ZrSiO4 forming in the coating directly during its formation play the role of a solid lubricant. Under optimal conditions for electrospark alloying of the titanium alloy, the coefficient of friction is 0.13, the wear is 6 m/km for a sliding velocity of 14 m/sec and a load of 2.56 MPa. Ceramics based on AlN ZrB2 can be recommended for use as wear-resistant and corrosion-resistant coatings. 相似文献
92.
Poly(N-isopropylacrylamide), NIPA, thermoresponsive hydrogels with well-defined concentrations of an electroactive probe, 1,1'-ferrocenedimethanol, Fc(MeOH)2, were prepared. The discontinuous reversible volume phase transition of such gels occurs at 32 +/- 1 degrees C and results in a release of approximately 93% of the solution from the polymeric network. Transport of Fc(MeOH)2 in both swollen and collapsed gels was studied using steady-state voltammetry and chronoamperometry at platinum microelectrodes. The diffusion coefficient of Fc(MeOH)2 in collapsed gels was approximately 2 orders of magnitude smaller than that in swollen gels. UV/vis spectroscopic studies showed that for 3.0% NIPA gel, the concentration of Fc(MeOH)2 in the collapsed phase was approximately 6 times higher than that in released solution and 4.5 times higher than in the original swollen gel. 相似文献
93.
A problem of a modal P-regulator synthesis for a linear multivariable dynamical system with uncertain (interval) parameters in state space is considered. The designed regulator has to place all coefficients of the system characteristic polynomial within assigned intervals. We have developed the approach proposed earlier in Dugarova and Smagina (Avtomat. i Telemech. 11 (1990) 176) and proved a direct correlation between interval system controllability and existence of robust modal P-regulator. 相似文献
94.
Electrospray ionization is a routine method in MS analysis of proteins and other biopolymers. Deposition of the electrospray products onto a conductive electrode is suggested here as a means to manufacture functionally active protein films. Recovery of the specific hydrolytic activity of the electrosprayed alkaline phosphatase (AP) was used as a probe for preservation of protein intactness in the electrospray deposition (ESD). It was shown that protein inactivation upon ESD is highly dependent on voltage and current used. Humidity and the presence of protective substances in solution also affect the process. Complete preservation of the enzyme activity was observed when the ESD was performed at low current and humidity in the presence of disaccharides. 相似文献
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S. F. Marenkin S. G. Mikhailov V. A. Morozova K. K. Palkina O. G. Koshelev 《Inorganic Materials》2003,39(10):1024-1027
Cd1 – x
Zn
x
As2 (x = 0.03, 0.05, 0.06) single crystals are grown by the Bridgman method, and their optical absorption spectra are measured. The introduction of Zn is shown to increase the band gap of CdAs2, by up to 14 meV at x = 0.06. The highest content of ZnAs2 incorporated into CdAs2 is 6 mol %. 相似文献
100.
Podchernyaeva Irina A. Lavrenko Vladimir A. 《Powder Metallurgy and Metal Ceramics》2001,40(1-2):44-48
The formation of a surface layer on low-alloyed steel during light-thermal treatment with a composite material based on Si3N4 Al2O3 was investigated. The working surfaces were studied using metallographic, x-ray diffraction, and electron-probe microanalysis. It was found that the corrosion-resistant phases Al2SiO5, (Fe, Cr)2O3, (Cr, Al) 2O3, and NiCrO4 formed in the alloyed layer, increasing its microhardness by 2-5 times and its corrosion resistance in sea water by more than two orders of magnitude. 相似文献