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991.
The deformation of a liquid capsule enclosed by a thin shell in a simple shear flow is studied numerically using an implicit immersed boundary method. We present a thin-shell model for computing the forces acting on the shell middle surface during the deformation within the framework of the Kirchhoff–Love theory of thin shells. This thin-shell model takes full account of finite-deformation kinematics which allows thickness stretching as well as large deflections and bending strains. For hyperelastic materials, the plane-stress assumption is used to compute the hydrostatic pressure and the incompressibility condition yields the thickness strain component and the corresponding change in the thickness. The stresses developing over the cross-section of the shell are integrated over the thickness to yield the stress and moment resultants which are then used to compute the forces acting on the shell middle surface. The immersed boundary method is employed for calculating the hydrodynamics and fluid–structure interaction effects. The location of the thin shell is updated implicitly using the Newton–Krylov method. The present numerical technique has been validated by several examples including an inflation of a spherical shell and deformations of spherical and oblate spheroidal capsules in the shear flow. 相似文献
992.
The oxygen permeability of films is relevant for packaging related and technical applications. An increasingly used test method for the measurement of oxygen permeability is the optical test method, because it allows a simple and cost-efficient measurement setup. This method is based on optical chemical sensors. However, not much is known about its validity. Therefore, method validation is necessary which is subject of this study. The optical method is compared with the carrier gas method for a variety of film samples. In the tested permeability range of 0.5–2500 cm3 (STP)·(m2 d bar)−1 both methods deviated less than 20% for zero and 50% relative humidity. 相似文献
993.
Ewelina Zatorska 《Journal of Differential Equations》2012,253(12):3471-3500
We consider the Cauchy problem for the system of equations governing flow of isothermal reactive mixture of compressible gases. Our main contribution is to prove sequential stability of weak solutions when the state equation essentially depends on the species concentration and the viscosity coefficients vanish on vacuum. Moreover, under additional assumption on the “cold” component of the pressure in the regions of small density, we prove the existence of weak solutions for arbitrary large initial data. 相似文献
994.
M. Gitterman 《Physica A》2009,388(7):1046-1056
The rate of a chemical reaction is expressed in terms of the correlation functions which are found from the full system of hydrodynamic equations in reactive systems. In the limiting cases one obtains all three types of behavior of reaction rates near the critical points found in experiments (slowing-down, speeding-up, insensitivity to criticality). This behavior depends on the number of reactive and inert components in a system, proximity and path of approach to the critical point. 相似文献
995.
Luigi C. Berselli Roger Lewandowski 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2012
We consider a 3D Approximate Deconvolution Model ADM which belongs to the class of Large Eddy Simulation (LES) models. We aim at proving that the solution of the ADM converges towards a dissipative solution of the mean Navier–Stokes equations. The study holds for periodic boundary conditions. The convolution filter we first consider is the Helmholtz filter. We next consider generalized convolution filters for which the convergence property still holds. 相似文献
996.
In this paper, a kind of β-amyloid peptide (Aβ1-16) conjugated gold nanoparticles (Aβ1-16@GNPs) are prepared and employed as colorimetric indicator for studying the interaction of β-amyloid peptide with metallic ions (e.g. Zn2+ and Ca2+). In the presence of Zn2+, mono-dispersing Aβ1-16@GNPs enable to form aggregates or attach on the SHG-44 (human glioma cell) cellular surface which results in significant color change of the solution. The experimental results indicate that Zn2+ can interact with Aβ1-16 and form Zn2+-β-amyloid peptide complexes. In particular, in the presence of Zn2+, a time-dependent interaction of cells with Aβ1-16@GNPs has been observed that may suggest different expression levels of β-amyloid peptide related proteins in various cell cycles. In addition, the aggregating/binding process can be easily reversed by adding EDTA, a good chelated ligand of Zn2+, which gives further proof of the interaction mechanism. 相似文献
997.
Novel p-tolylimido rhenium(V) complexes [Re(p-NC6H4CH3)X2(hpb)(PPh3)] and [Re(p-NC6H4CH3)(hpb)2(PPh3)]X (X = Cl, Br) have been obtained in the reactions of [Re(p-NC6H4CH3)X3(PPh3)2] with 2-(2-hydroxyphenyl)-1H-benzimidazole (Hhpb). The compounds were identified by elemental analysis IR, UV-Vis spectroscopy and X-ray crystallography. The electronic structures of the complex [Re(p-NC6H4CH3)Cl2(hpb)(PPh3)] and the cation [Re(p-NC6H4CH3)(hpb)2(PPh3)]+ have been calculated with the density functional theory (DFT) method. Additional information about binding in the [Re(p-NC6H4CH3)Cl2(hpb)(PPh3)] and [Re(p-NC6H4CH3)(hpb)2(PPh3)]+ has been obtained by NBO analysis. The electronic spectra of [Re(p-NC6H4CH3)Cl2(hpb)(PPh3)] and [Re(p-NC6H4CH3)(hpb)2(PPh3)]Cl were investigated at the TDDFT level employing B3LYP functional in combination with LANL2DZ. 相似文献
998.
《Journal of Coordination Chemistry》2012,65(3):467-478
Abstract The chemical and direct electrochemical syntheses of copper, cobalt, nickel and zinc chelates of 2-[N-tosylamine)benzaldoxime (L1H2) and 2-[N-tosylamine)benzal-O-methyloxime (L2H) are reported. On the basis of the elemental analyse IR and EPR spectra and magnetic properties, dimeric structures ML are suggested from L1H2 under the conditions of the chemical synthesis, while electrosynthesis leads to the monomeric complexes M(L1H)2. Using L2H as a ligand, only the chelates ML2 2 are formed, regardless of the method of synthesis. The copper dimers CuL1 have antiferromagnetic properties, while the chelates M(L1H)2 and ML2 have normal magnetic moments. In agreement with the magnetic properties and literature data on structures of four-coordinate complexes a tetrahedral structure is assigned. 相似文献
999.
Jordanka Petrova Nikolai G. Vassilev Marko Kirilov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):457-463
Abstract The reaction of the lithium derivative of diethyl ester of phenylmethanephosphonic acid (1-Li) with alkanones, cycloalkanones, alkylaryl and diarylketones 2s-b is studied at -70°C in THF. The corresponding adducts-diethyl esters of l-phenyl-2,2-dialkyl(phenyl)-2-hydroxyethanephosphonic acids 3s-h are isolated, their yields being usually higher at short reaction time. The olefination of 3-Li as well as of 3 (both by thermolysis or in acidic media) proceeds in low degree, while in the case of 3-Na the yields of alkenes 4 are good. The relative configurations of 3b. 31 and 3g are determined by IR and NMR-spectra, as well as by their stereospecific olefination. “Threo”-stereoselectivity of the addition stage of the reaction of 1-Li with 2b, 21 and 2g is observed, the “threo”/“erythro” ratio remaining independent on the reaction time. 相似文献
1000.
Sahar Al Akoum-Ebrik Mohamed Ansar Rahima Mouhoub Claude Vaccher Marie-Pierre Vaccher Nathalie Flouquet 《光谱学快报》2013,46(5):925-944
The enantiomeric composition and absolute configuration of 4-Amino-3-(benzo[b]furan-2-yl)-Butanoic Acids and of 4-Amino-3-(thien-2-yl)-Butanoic Acids 1 may be accurately determined by 1H and 13C nuclear magnetic resonance analysis of the corresponding derivatives 3 prepared by reaction with chiral reagents. Correlation with HPLC is signaled. 相似文献