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71.
72.
Mirsaidov U Timashev SF Polyakov YS Misurkin PI Musaev I Polyakov SV 《The Analyst》2011,136(3):570-576
The functional properties of many technological surfaces in biotechnology, electronics, and mechanical engineering depend to a large degree on the individual features of their nanoscale surface texture, which in turn is a function of the surface manufacturing process. Among these features, the surface irregularities and self-similarity structures at different spatial scales, especially in the range of 1 to 100 nm, are of high importance because they greatly affect the surface interaction forces acting at a nanoscale distance. An analytical method for parameterizing the surface irregularities and their correlations in nanosurfaces imaged by atomic force microscopy (AFM) is proposed. In this method, flicker noise spectroscopy--a statistical physics approach--is used to develop six nanometrological parameters characterizing the high-frequency contributions of jump- and spike-like irregularities into the surface texture. These contributions reflect the stochastic processes of anomalous diffusion and inertial effects, respectively, in the process of surface manufacturing. The AFM images of the texture of corrosion-resistant magnetite coatings formed on low-carbon steel in hot nitrate solutions with coating growth promoters at different temperatures are analyzed. It is shown that the parameters characterizing surface spikiness are able to quantify the effect of process temperature on the corrosion resistance of the coatings. It is suggested that these parameters can be used for predicting and characterizing the corrosion-resistant properties of magnetite coatings. 相似文献
73.
Huang Z Luo Z Geletii YV Vickers JW Yin Q Wu D Hou Y Ding Y Song J Musaev DG Hill CL Lian T 《Journal of the American Chemical Society》2011,133(7):2068-2071
The abundant-metal-based polyoxometalate complex [Co(4)(H(2)O)(2)(PW(9)O(34))(2)](10-) is a hydrolytically and oxidatively stable, homogeneous, and efficient molecular catalyst for the visible-light-driven catalytic oxidation of water. Using a sacrificial electron acceptor and photosensitizer, it exhibits a high (30%) photon-to-O(2) yield and a large turnover number (>220, limited solely by depletion of the sacrificial electron acceptor) at pH 8. The photocatalytic performance of this catalyst is superior to that of the previously reported precious-metal-based polyoxometalate water oxidation catalyst [{Ru(4)O(4)(OH)(2)(H(2)O)(4)}(γ-SiW(10)O(36))(2)](10-). 相似文献
74.
75.
Darshan C Kundaliya Reeta Vij AA Tulapurkar U Vaidya R Pinto RG Kulkarni 《Pramana》2002,58(5-6):1041-1044
Electrical resistance (R) measurements of a bulk La0.33Nd0.33Ca0.33MnO3 perovskite in magnetic fields up to 40 kOe have revealed anomalous temperature hysteretic effects both in 0 Oe and 20 kOe
magnetic fields. The sharp peak observed in the R vs. T plot indicates the occurrence of metal-to-insulator (M-I) transition at a temperature of T
MI=110 K and 140 K, for cooling and warming paths, respectively. An applied magnetic field of 20 kOe reduces the resistance
and shifts T
MI to 160 K and 185 K for cooling and warming, respectively. We have observed a much higher resistance in the cooling path than
in the warming path leading to the hysteretic resistance ratio (R
cool/R
warm) of 200 at 110 K and 1.8 at 160 K for 0 Oe and 20 kOe, respectively. Record values of colossal magnetoresistance (CMR) have
been achieved. The CMR value reaches nearly 99% in the temperature ranges of 90 K to 140 K and 90 K to 170 K for 20 kOe and
40 kOe magnetic fields in the cooling mode, respectively. The observed unusual behavior is attributed to the co-existence
of La-rich and Nd-rich domains assumed to be distributed randomly in the compound. 相似文献
76.
A. M. Musaev 《Russian Physics Journal》1997,40(5):462-464
The results are presented of the experimental detection and investigation of the phenomenon of the drift of excitons in an
inhomogeneous electric field. The investigations were performed on silicon structures with Shottky barriers at 4.2 K. A study
was made of the influence of the photoexcitation intensity and electric field strength on the breakdown dynamics of the structure.
The experimental results were used to show that breakdown of a reverse-biased Shottky barrier involves a narrowing of the
width of the space-charge region due to a drift of excitons in the inhomogeneous electric field and to recombination of electrons
on ionized impurity centers of the barrier.
Kh. I. Amirkhanov Physics Institute, Dagestan Scientific Center, Russian Academy of Sciences. Translated from Izvestiya Vysshikh
Uchebnykh Zavedenii, Fizika, No. 5, pp. 67–69, May, 1997. 相似文献
77.
78.
Institute of New Chemical Problems, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 2, pp. 8–16, March–April, 1990. 相似文献
79.
Institute of Mathematics and Mechanics of the Academy of Sciences of the Azerbaidzhan SSR, Baku. Translated from Prikladnaya Mekhanika, Vol. 26, No. 10, pp. 16–21, October, 1990. 相似文献
80.
We have studied the peak effect (PE) phenomenon in single crystals of weakly pinned superconductors CeRu2 and 2H-NbS2. 2H-NbS2 is iso-structural and iso-electronic to 2H-NbSe2, whose similarity with CeRu2 as regards the PE representing the order-to-disorder transformation of the flux line lattice was claimed some time ago. We
report on the step change in equilibrium magnetization across the peak effect in CeRu2. We also present the vortex phase diagram of 2H-NbS2 obtained from the magnetization data, and compare the PE phenomenon in 2H-NbS2 and 2H-NbSe2. 相似文献