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101.
A mixture theory is developed for multi-component micropolar porous media with a combination of the hybrid mixture theory and the micropolar continuum theory. The system is modeled as multi-component micropolar elastic solids saturated with multi- component micropolar viscous fluids. Balance equations are given through the mixture theory. Constitutive equations are developed based on the second law of thermodynamics and constitutive assumptions. Taking account of compressibility of solid phases, the volume fraction of fluid as an independent state variable is introduced in the free energy function, and the dynamic compatibility condition is obtained to restrict the change of pressure difference on the solid-fluid interface. The constructed constitutive equations are used to close the field equations. The linear field equations are obtained using a linearization procedure, and the micropolar thermo-hydro-mechanical component transport model is established. This model can be applied to practical problems, such as contaminant, drug, and pesticide transport. When the proposed model is supposed to be porous media, and both fluid and solid are single-component, it will almost agree with Eringen's model. 相似文献
102.
Multi-component Dirac equation hierarchy and its multi-component integrable couplings system 总被引:2,自引:0,他引:2 下载免费PDF全文
A general scheme for generating a multi-component
integrable equation hierarchy is proposed. A simple
3M-dimensional loop algebra \tilde{X} is produced. By taking
advantage of \tilde{X}, a new isospectral problem is established
and then by making use of the Tu scheme the multi-component Dirac
equation hierarchy is obtained. Finally, an expanding loop algebra
\tilde{F}M of the loop algebra \tilde{X} is presented. Based
on the \tilde{F}M, the multi-component integrable coupling
system of the multi-component Dirac equation hierarchy is
investigated. The method in this paper can be applied to other
nonlinear evolution equation hierarchies. 相似文献
103.
104.
Dr. Abir Goswami Dr. Sudhakar Gaikwad Prof. Dr. Michael Schmittel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(9):2997-3001
Enzymes are encoded with a gamut of information to catalyze a highly selective transformation by selecting the proper reactants from an intricate mixture of constituents. Mimicking biological machinery, two switchable catalysts with differently sized cavities and allosteric control are conceived that allow complementary size-selective acyl transfer in an on/off manner by modulating the effective local concentration of the substrates. Selective activation of one of two catalysts in a mixture of reactants of similar reactivity enabled upregulation of the desired product. 相似文献
105.
2-取代-4(3H)-喹唑啉酮在Br(o)nsted酸性功能化离子液体中的微波合成 总被引:3,自引:0,他引:3
以N-甲基咪唑、吡啶为起始原料,合成了二种新型Br(o)nsted酸性功能化离子液体:1-(4-磺酸基)苄基-3-甲基咪唑硫酸氢根盐(3a),N-(4-磺酸基)苄基吡啶硫酸氢根盐(3b),以其作为反应介质与催化剂,研究了2-取代-4(3H)-喹唑啉酮的三组分、一锅法微波合成.结果表明,当n(2-氨基苯甲酸):n(酰氯):n(乙酸铵):n(3a或3b)=1:1.2:1.5:0.1时,反应6 min即可完成,产率81%~95%.离子液体经减压蒸馏、真空干燥可重复使用3次,催化活性基本保持不变. 相似文献
106.
以N-甲基咪唑、吡啶为起始原料,合成了二种新型BrФnsted酸性功能化离子液体:1-(4-磺酸基)苄基-3-甲基咪唑硫酸氢根盐(3a),N-(4-磺酸基)苄基吡啶硫酸氢根盐(3b),以其作为反应介质与催化剂,研究了2-取代-4(3H)-喹唑啉酮的三组分、一锅法微波合成.结果表明,当n(2-氨基苯甲酸):n(酰氯):n(乙酸铵):n(3a或3b)=1:1.2:1.5:0.1时,反应6min即可完成,产率81%~95%.离子液体经减压蒸馏、真空干燥可重复使用3次,催化活性基本保持不变. 相似文献
107.
Dihydropyrimidinones/thiones (DHPM’s) have been prepared by one-pot condensation of methyl acetoacetate, aldehydes, urea/thiourea in the presence of heteropoly-11-tungsto-1-vanadophosphoric acid, H4[PVW11O40]?·?32H2O, (HPV) supported on activated natural clay (HPVAC) under solvent-free reaction condition have been proposed. The DHPM derivatives were identified through elemental analysis and melting point measurements and characterized by FT-IR, 1H-NMR, 13C-NMR spectroscopic methods. 相似文献
108.
Mahmoud. Abd El Aleem. Ali. Ali. El-Remaily 《催化学报》2015,(7):1124-1130
A series of coumarin-chalcone hybrid compounds and coumarins linked to pyrazoline was synthe-sized in good yield and short time using a simple and efficient method. This method involved the one-pot reaction of salicylaldehyde, an α-ketoester and an aromatic aldehyde (in the case of the coumarin-chalcone derivatives) in addition to hydrazine hydrate (in the case of the pyrazolyl cou-marins) in the presence of a catalytic amount of bismuth triflate [Bi(OTf)3, 5 mol%]. The synthesized compounds showed scavenging activity towards the free radical 2,2-diphenyl-1-picrylhydrazyl. All compounds were characterized using IR,1H NMR and13C NMR spectroscopy. 相似文献
109.
An efficient procedure for the synthesis of a novel class of benzylidene-2-alkoxy-4-aryl-6,7-dihydro-5H-cyclopenta[b]pyridine-, -5,6,7,8-tetrahydroquinoline and/or -6,7,8,9-tetrahydro-5H-cyclohepta[b]pyridine-3-carbonitrile was introduced through the one-pot multi-component reaction of cyclopentanone, cyclohexanone, and/or cycloheptanone with different aromatic aldehydes and malononitrile. The same products were also produced by classical route by the two-component reaction of dibenzylidine cyclopentanone, cyclohexanone, and/or cycloheptanone derivatives with malononitrile. The reactions were achieved using sodium alkoxide solution as catalyst and reagent. 相似文献
110.
A fast, general, environmentally friendly, and facile method for preparation of 5, 5-disubstituted hydantoins from the reaction between ketone (or aldehyde) derivatives with KCN and ammonium carbonate under microwave irradiation is presented. The microwaves remarkably accelerated this reaction, the reaction times decreased dramatically, the reaction conditions were milder, and the yields were also greater. Also a comparative study of microwave versus classical conditions has been done. All the products were characterized by infrared, NMR, and CHN analysis, and their melting points are identical to those of the known compounds reported in the literature. This method might be useful in the future for the preparation of similar derivatives. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献