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21.
In this paper, we deal with the nonlinear second-order differential equation with damped vibration term involving p-Laplacian operator. Of particular interest is the resolution of an open problem. An interesting outcome from our result is that we can obtain the fast homoclinic solution with general superlinear growth assumption in suitable Sobolev space. To our knowledge, our theorems appear to be the first such result about damped vibration problem with p-Laplacian operator.  相似文献   
22.
Acta Mathematica Sinica, English Series - The main purpose of this article is to study the calculating problem of the sixth power mean of the two-term exponential sums, and give an interesting...  相似文献   
23.
As a sequel to [8], we investigate here the behaviour of thetrivial extensions of tilted algebras under stable equivalence.It will be shown that if a finite-dimensional symmetric algebra is stably equivalent to the trivial extension of a tilted algebraB, then is the trivial extension of some tilted algebra A whichhas the same type as B.  相似文献   
24.
Present paper presents a derivation of Luikov equations applicable to sublimation-drying. The physical situation and transfer mechanism are elucidated clearly. The coefficients appearing in Luikov equations are given in a more explicit way. Some formulation mistakes in recent publications are indicated.
Anwendung der Luikov-Gleichungen auf die Sublimationstrocknung
Zusammenfassung Die Untersuchung bezieht sich auf eine Ableitung der Luikov-Gleichungen, mittels deren sich der Vorgang der Sublimationstrocknung analysieren läßt. Physikalische Anfangssituation und Austauschmechanismen werden klar herausgestellt und die in den Luikov-Gleichungen auftretenden Koeffizienten in expliziter Weise angegeben. Ferner erfolgt Hinweis auf Formulierungsfehler in jüngeren Veröffentlichungen.

Nomenclature C M v/V f, concentration of vapor, kg/m3 - c pv specific heat of vapor at constant pressure, J/kg K - c pw specific heat of adsorbed water at constant pressure, J/kg K - c s specific heat of solid skeleton, J/kg K - C s M s/V f, concentration of solid skeleton, kg/m3 - C w M w/V f, concentration of adsorbed water, kg/m3 - f V w/V f, volumetric fraction of adsorbed water - j F mass flux of vapor by diffusion (Fick) transfer, kg/m2 s - j D mass flux of vapor by filtration (Darcy) transfer, kg/m2 s - j v total mass flux of vapor, kg/m2 s - k permeability, m2 - M s mass of solid skeleton, kg - M v mass of vapor in pores, kg - M w mass of adsorbed water, kg - P pressure, Pa - q heat flux, W/m2 - R gas constant, J/kg K - T temperature, K - V f volume of the framework of porous medium, m3 - V v volume of vapor in porous medium, m3 - V w volume of the absorbed water, m3 Greek symbols /(c p), effective thermal diffusivity, m2/s - m effective vapor diffusivity in porous medium, m2/s - p R T /, Luikov pressure diffusivity, m2/s - +f, porosity of the porous medium - effective thermal conductivity of porous body, W/m K - dynamic viscosity of vapor, kg/m s - kinematic viscosity, m2/s - Ck/=k/, Luikov filtration motion coefficient, s - V v/V f, volumetric fraction of vapor - density of absorbed water, kg/m3 - (c p) M v c pv+M s c s+M w c pw /V f=Cc pv+C s c s+fc pw, effective product of density and specific heat of humid porous body, J/m3K  相似文献   
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Methylene blue-intercalated alpha-zirconium phosphate (MBZrP) micro particles in deionized water were deposited onto the surface of graphite powder to prepare graphite powder-supported MBZrP, which was subsequently dispersed into methyltrimethoxysilane-derived gels to yield a conductive composite. The composite was used as electrode material to fabricate a surface-renewable, rigid, leak-free carbon ceramic composite electrode, bulk-modified with methylene blue (MB). In the configuration, alpha-zirconium phosphate was employed as a solid host for MB, which acted as a catalyst. Graphite powder ensured conductivity by percolation, the silicate provided a rigid porous backbone and the methyl groups endowed hydrophobicity and thus limited the wetting section of the modified electrode. Peak currents of the MBZrP-modified electrode were surface-confined at low scan rates but diffusion-controlled at high scan rates. Square-wave voltammetric study revealed that MBZrP immobilized in carbon ceramic matrix presented a two-electron, three-proton redox process in acidic aqueous solution with pH ranged from 0.44 to 2.94. In addition, the chemically modified electrode showed an electrocatalytic activity toward nitrite reduction at +0.15 V ( vs. Ag/AgCl) in acidic aqueous solution (pH=0.44). The linear range and detection limit are 1x10(-6)-4x10(-3) mol x L(-1) and 1.5x10(-7) mol x L(-1), respectively.  相似文献   
28.
纳米级NiTiO3粉体的合成   总被引:3,自引:0,他引:3  
以H2TiO3,H2O2及NiCl2为主要原料,用化学共沉淀法制备了纳米级NiTiO3。确定了反应物H2TiO3,H2O2,NH3的最佳摩尔比为1:8:2,用不同的退火温度和退火时间对样品处理得到相应粒径的纳米级粉体。  相似文献   
29.
A water-soluble nanometer-scale metallocapped polyrotaxane has been prepared by the inclusion complexation of azo-calixarenes with metallo-bridged bis(beta-CD)s, displaying highly selective binding for Ca(2+).  相似文献   
30.
The molecular structure and binding, as well as infrared and electronic spectroscopic properties for the title complex Cu(mnt)(dmbpy)(mnt(2-)=maleonitriledithiolate, dmbpy=4,4'-dimethyl-2,2'-bipyridine) were studied in this paper. With semi-empirical PM3 and non-empirical DFT (B3LYP/6-311G*) methods, the molecular geometry of the complex was optimized and corresponding vibrational spectra in the gaseous state were obtained. The calculated results derived from DFT were more reasonable than those from PM3. The point group of Cu(mnt)(dmbpy) in isolated gaseous state was C(2), in which Cu(II) adopted a distorted tetrahedral geometry and the dihedral angle between the N(2)Cu and S(2)Cu planes was about 29.814 degrees. And a complete assignment to the IR spectra of such a complicated molecule was exhibited. With ZINDO/S method an electronic spectrum was calculated. The results showed that the calculated values generally agreed with the observed ones. And a detailed explain was made on its electronic spectra.  相似文献   
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