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661.
In this paper, after a brief discussion on the implicit constitutive relations used in thermoelasticity, based on Fox’s [1] work, we derive a general implicit relation for the heat flux vector. In the section following that we use the methodology suggested by Rajagopal [2] and [69] whereby we derive a class of implicit constitutive relations for q and we show that by selecting appropriate functions appearing in the formulation, we can obtain as special cases the Fourier heat conduction and the Maxwell-Cattaneo-Fox model. We do not discuss the implications of the second law of thermodynamics. 相似文献
662.
A numerical method for calculation of strong radiation for 2D reactive air is developed. Governing equations are taken to
be 2D, compressible Reynolds-average Navier–Stokes and species transport equations. Also, radiation heat flux is evaluated
using a model of discrete ordinate method. A multiband model is used to construct absorption coefficients. Tangent slab approximation
is assumed to determine the characteristic parameters needed in the Discrete Ordinates Method. 相似文献
663.
Based on the method of energy principle, an analytical approach for computing the capillary force for sphere/sphere geometry is presented in this paper. In modeling the capillary force, we consider spheres with both equal and non-equal radii, for both symmetric and asymmetric configurations at liquid/solid interfaces. We use numerical analysis to investigate the validity and efficiency of the derived model. The effect of various parameters including humidity, distance between two spheres, radii of spheres and contact angles on the meniscus force are investigated. Finally the results obtained from the model are compared with experimental measurements, and the accuracy and precision of the presented approach is verified. 相似文献
664.
Malakoutikhah M Teixidó M Giralt E 《Angewandte Chemie (International ed. in English)》2011,50(35):7998-8014
Advances in the field of shuttle-mediated drug delivery have been made in the last decade; however, the treatment of brain disorders still remains a great challenge because of the presence of the blood-brain barrier (BBB), a structure that limits the access of drugs to their site of action in the central nervous system. Several strategies have been proposed to enhance the transport of drugs across the BBB. In this Review, we focus on the vector-mediated approach, in which a drug is coupled to a molecule (shuttle) that has the ability to cross the BBB and deliver the drug to the brain. 相似文献
665.
Morteza Seddighin 《Linear algebra and its applications》2011,434(5):1395-1408
We will study the slant joint antieigenvalues and antieigenvectors of pairs of operators that belong to the same closed normal subalgebra of the algebra of bounded operators on a separable Hilbert space. This extends the slant antieigenvalue theory from single normal operators to pairs of normal operators. Our results may be viewed as extensions of the Greub-Rheinboldt inequality from two positive operators to two normal operators. 相似文献
666.
In the present study the solubilities of two antifungal drugs of ketoconazole and clotrimazole in supercritical carbon dioxide were measured using a simple static method. The experimental data were measured at (308 to 348) K, over the pressure range of (12.2 to 35.5) MPa. The mole fraction solubilities ranged from 0.2 · 10?6 to 17.45 · 10?5. In this study five density based models were used to calculate the solubility of drugs in supercritical carbon dioxide. The density based models are Chrastil, modified Chrastil, Bartle, modified Bartle and Mendez-Santiago and Teja (M–T). Interaction parameters for the studied models were obtained and the percentage of average absolute relative deviation (AARD%) in each calculation was displayed. The correlation results showed good agreement with the experimental data. A comparison among the five models revealed that the Bartle and its modified models gave much better correlations of the solubility data with an average absolute relative deviation (AARD%) ranging from 4.8% to 6.2% and from 4.5% to 6.3% for ketoconazole and clotrimazole, respectively. Using the correlation results, the heat of drug–CO2 solvation and that of drug vaporization was separately approximated in the range of (?22.1 to ?26.4 and 88.3 to 125.9) kJ · mol?1. 相似文献
667.
Saeed Balalaie Hassan MotaghediMorteza Bararjanian Daryoush Tahmassebi Hamid Reza Bijanzadeh 《Tetrahedron》2011,67(47):9134-9141
An efficient method for the stereoselective synthesis of 3-(diarylmethylene)-2-oxindoles and 3-(arylmethylene)-2-oxindoles via carbopalladation is described. In this approach, an Ugi-4-component reaction (4-CR) adduct was used as the starting material. A one-pot sequence involving intermolecular carbopalladation C-H activation/C-C bond formation efficiently afforded the oxindole derivatives. 相似文献
668.
Saeed Balalaie Morteza BararjanianSaeedeh Hosseinzadeh Frank RomingerHamid Reza Bijanzadeh Eckardt Wolf 《Tetrahedron》2011,67(38):7294-7300
An efficient strategy for the one-pot syntheses of indolo[1,2-a]quinoxalinones catalyzed by CuI have been developed. The procedures combine the Ugi four-component reaction of aldehydes, 2-iodoaniline, 2-indole carboxylic acid, and isocyanides followed by the copper-catalyzed intramolecular N-arylation of the Ugi product in one-pot procedure, which afford the desired products in good to very good yields. 相似文献
669.
Morteza BararjanianSaeedeh Hosseinzadeh Saeed Balalaie Hamid Reza Bijanzadeh 《Tetrahedron》2011,67(14):2644-2650
Potentially bioactive 3-(anilinoarylmethylene)-2-oxindoles as Hesperadin analogoues have been synthesized via a two-step procedure: (a) an Ugi-4MCR and (b) reaction of the Ugi adduct with aniline in the presence of a palladium catalyst via domino Heck/Buchwald reaction. In all cases, a single isomer with the Z-configuration was obtained in good to high yields. 相似文献
670.
Seyed Javad Ahmadi Sodeh Sadjadi Morteza Hosseinpour 《Monatshefte für Chemie / Chemical Monthly》2011,44(24):1163-1168