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941.
In view of wide potential use as p-type oxide semiconductor of titanium monoxide (TiO), it is deposited in this work by using high power impulse magnetron sputtering (HIPIMS), which is known to provide less hysteresis effect in reactive sputtering and better control in stoichiometry. A strong correlation among the preparation parameters on the microstructure and optoelectrical characteristics of the obtained Ti-O films are investigated.Experimental results show that the crystallinic cubic γ-TiO can be directly grown on unheated glass substrate. In regard to the effects of substrate bias and post-annealing, the as-grown γ-TiO transfers into rutile (R-TiO2) at a critical substrate bias voltage of −125 V or post-annealing temperature of 500 °C. For the purpose of p-type channel layer in transistor, the optimum γ-TiO film exhibiting a high hole mobility of 8.2 cm2/V s is grown at the substrate bias voltage of −25 V and followed by the post-annealing at 400 °C. 相似文献
942.
This article presents the implementation and application, to two complex machines, of two holography methods called CIBNAH (Complex Intensity Based Near-field Acoustic Holography) and MRNAH (Multi Reference Near-field Acoustic Holography) based on residual spectra. The first is a newly developed method that uses complex sound intensity as its basis and hence bypasses the need for reference signals. Here, several approaches are presented to validate both methods and to investigate each method’s advantages and limitations. 相似文献
943.
《AEUE-International Journal of Electronics and Communications》2014,68(8):763-766
There is a considerable interest in the antennas which have high power handling capacity with beam steering functionality. The design of narrow side waveguide slot-array antenna for high power applications is introduced in this paper. An approach to achieve a uniform radiation slot waveguide antenna is presented. The large scale array antenna can be composed of such antenna cells. Moreover, it is possible to realize beam steering in the azimuth direction by adjusting the broad wall dimension of the waveguide. Besides, this slot waveguide antenna is expected to have high power handling capacity in vacuum environment, because there is no dielectric or electric field enhancement inside the antenna. 相似文献
944.
This paper presents an analysis of the combining mechanism for status information postulated by the mathematical formulation of the theory of status characteristics and expectation states. Six lemmas on the basic features of the combining mechanism are derived from the formulation and discussed. Further, four theorems that illustrate the implications of the particular combining mechanism for power and prestige orders are presented and proven. 相似文献
945.
Cyanoacetamides 3 were prepared via reacting ethyl cyanoacetate with benzylamine. Yields and reaction times needed for reaction completion at room temperature, by microwaves (μω) heating and under ultrasound (US) irradiations are compared. The formed cyanoacetamides were coupled with aromatic diazonium salts and the formed arylhydrazones were used as precursors to title triazoles and pyrazoles via reacting the former with hydroxylamine and chloroacetonitrile. Yields of products formed via conventional heating are compared with those of μω and US irradiation. 相似文献
946.
947.
R.Y. Hong Y.J. Wu G.Q. Di B. Xu D.G. Wei 《Journal of magnetism and magnetic materials》2009,321(8):1106-1110
Bi-substituted yttrium iron garnet (Bi-YIG, Bi1.8Y1.2Fe5O12) nanoparticles were prepared by microwave-assisted co-precipitation as well as conventional co-precipitation using ammonia aqueous solution as precipitant. The nanoparticles were characterized by thermal gravity-differential thermal analysis, X-ray powder diffraction, transmission electron microscopy, dynamic light scattering and vibrating sample magnetometer, respectively. The Faraday rotation of Bi-YIG modified PMMA slices was also investigated. Results demonstrate that the Bi-YIG nanoparticles prepared by microwave-assisted co-precipitation show smaller particle size and higher Faraday rotation than those prepared by conventional co-precipitation. 相似文献
948.
949.
950.
An improved progressive preconditioning method for analyzing steady inviscid and laminar flows around fully wetted and sheet‐cavitating hydrofoils is presented. The preconditioning matrix is adapted automatically from the pressure and/or velocity flow‐field by a power‐law relation. The cavitating calculations are based on a single fluid approach. In this approach, the liquid/vapour mixture is treated as a homogeneous fluid whose density is controlled by a barotropic state law. This physical model is integrated with a numerical resolution derived from the cell‐centered Jameson's finite volume algorithm. The stabilization is achieved via the second‐and fourth‐order artificial dissipation scheme. Explicit four‐step Runge–Kutta time integration is applied to achieve the steady‐state condition. Results presented in the paper focus on the pressure distribution on hydrofoils wall, velocity profiles, lift and drag forces, length of sheet cavitation, and effect of the power‐law preconditioning method on convergence speed. The results show satisfactory agreement with numerical and experimental works of others. The scheme has a progressive effect on the convergence speed. The results indicate that using the power‐law preconditioner improves the convergence rate, significantly. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献