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991.
Ion-beam sputter-deposited alloy films of Co/sub 74/Fe/sub 6/B/sub 15/Si/sub 5/ and Fe/sub 75/Ni/sub 5/B/sub 15/Si/sub 5/ were examined for their magnetic and structural properties. Films were characterized by ferromagnetic resonance, vibrating sample magnetometry, and extended X-ray absorption fine structure (EXAFS) analysis. Using atomic parameters deduced from EXAFS modeling and fitting procedures, magnetic properties were calculated with no adjustable parameters. Correlation between perpendicular FMR measurements and EXAFS first-shell modeling suggests a low-temperature formation of cobalt-borides in the Co/sub 74/Fe/sub 6/B/sub 15/Si/sub 5/ alloy. Annealed Fe/sub 75/Ni/sub 5/B/sub 15/Si/sub 5/ samples did not display evidence of structural and/or magnetic instabilities until the onset of long-range crystallization near T/sub ann/=400 degrees C.<> 相似文献
992.
A. J. Hermans 《Journal of Engineering Mathematics》1991,25(1):63-75
The purpose of this paper is to provide a mathematical tool to improve the optimal design of ship forms. It is common practice that hull forms are designed such that they have minimum wave resistance in calm water. In this paper a theory is described by which the effect of short waves may be incorporated.The basic tool we use is the ray theory. First, the appropriate free-surface condition is shown. Then, the standard ray method, well-known in geometric optics, is formulated in the fluid region and at the free surface. After an elimination process the eiconal equation and the transport equation are obtained. The characteristic equation for the nonlinear eiconal equation is derived, keeping in mind that the characteristics are not perpendicular to the wave fronts, due to the effect of the double-body potential due to the forward speed of the ship, which is assumed to be a good approximation for the steady potential.Numerical computations are carried out by means of the RK4 method to obtain the ray pattern. After some manipulations the amplitude may be computed just as well. Finally, the nonlinear added-resistance force is calculated. Pictures of ray patterns for several angles of incidence are shown. Also the forces are shown. 相似文献
993.
I. S. Panidi V. A. Trofimov N. S. Lepikhina 《Chemistry and Technology of Fuels and Oils》2006,42(6):440-445
Equations are proposed for calculating the molar volume of liquid hydrocarbons used in production of surfactants. With such
data, it will be possible to calculate most of the physicochemical properties of these hydrocarbons to solve many process
problems.
__________
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 6, pp. 39–41, Novemmber–December, 2006. 相似文献
994.
Fernando J Beltrn F Javier Rivas Olga Gimeno 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(9):973-984
Photocatalytic ozonation (1O3 + VUV + TiO2), ozonation (O3), catalytic ozonation (O3 + TiO2), ozone photolysis (O3 + VUV), photocatalysis (TiO2 + VUV) and photolysis (VUV) have been compared in terms of formation of intermediates, extent of, mineralization (TOC, COD, chloride, nitrate) and kinetics in the aqueous treatment of three phenols (phenol, p‐chlorophenol and p‐nitrophenol). In all cases, photocatalytic ozonation led to lower degradation times for chemical oxygen demand and total organic carbon removal. Intermediates formed were similar in the different oxidation systems with some exceptions. They can be classified into three different types: polyphenols (resorcinol, catechol, hydroquinone), unsaturated carboxylic acids (maleic and fumaric acids) and saturated carboxylic acids (glyoxylic, formic and oxalic acids). First order kinetic equations have been checked for the oxidation processes studied in the case of the parent compound. Rate constants of these systems have also been calculated. Copyright © 2005 Society of Chemical Industry 相似文献
995.
Velocity profiles for the inner and outer flow regions of annuli are proposed for the turbulent flow of drag reducing fluids. Theoretical expressions for friction factors are developed. From the shear stress equations and the velocity profiles, estimates for the entrance lengths are given. 相似文献
996.
A.J. Neilson 《International Journal of Impact Engineering》1985,3(2):137-142
The experimental results for the perforation energy of mild steel plate struck by flat-ended, non-deforming, cylindrical penetrators have been correlated using the principles of dimensional analysis. A correlation is presented for long penetrators. It is shown that for short penetrators a different response of the target is observed and that, at present, there are insufficient published data to produce a unifying correlation. 相似文献
997.
998.
The manifestation of elastic effects during the filtration of polymer solutions is analyzed theoretically.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 3, pp. 390–397, September, 1985. 相似文献
999.
Papandriopoulos J. Evans J. Dey S. 《Wireless Communications, IEEE Transactions on》2005,4(6):2705-2715
How can we achieve the conflicting goals of reduced transmission power and increased capacity in a wireless network, without attempting to follow the instantaneous state of a fading channel? In this paper, we address this problem by jointly considering power control and multiuser detection (MUD) with outage-probability constraints in a Rayleigh fast-fading environment. The resulting power-control algorithms (PCAs) utilize the statistics of the channel and operate on a much slower timescale than traditional schemes. We propose an optimal iterative solution that is conceptually simple and finds the minimum sum power of all users while meeting their outage targets. Using a derived bound on outage probability, we introduce a mapping from outage to average signal-to-interference ratio (SIR) constraints. This allows us to propose a suboptimal iterative scheme that is a variation of an existing solution to a joint power control and MUD problem involving SIR constraints. We further use a recent result that transforms complex SIR expressions into a compact and decoupled form, to develop a noniterative and computationally inexpensive PCA for large systems of users. Simulation results are presented showing the closeness of the optimal and mapped schemes, speed of convergence, and performance comparisons. 相似文献
1000.
Ramirez-Angulo J. Sawant M.S. Lopez-Martin A. Carvajal R.G. 《Electronics letters》2005,41(10):570-572
A high-performance compact current mirror implementation with very low input resistance, very high output resistance, high copying accuracy, low input and output voltage supply requirements and high bandwidth is proposed. The circuit characteristics are validated with simulations in 0.5 /spl mu/m CMOS technology and with experimental results. 相似文献