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Nikolai A. Kudryashov Dmitry I. Sinelshchikov 《Applied mathematics and computation》2012,218(12):6991-6997
The family of fifth order nonlinear evolution equations is studied. Some traveling wave elliptic solutions are found. The classification of these exact solutions is given. 相似文献
995.
Algebra of Octonions is used to construct singular viscosity solutions of fully nonlinear Hessian elliptic equations. These
equations are written in the form of an Isaacs equation. 相似文献
996.
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998.
Latifa Ait Mahiout Nikolai Bessonov Bogdan Kazmierczak Vitaly Volpert 《Mathematical Methods in the Applied Sciences》2023,46(2):1740-1751
Viral infection in cell culture and tissue is modeled with delay reaction-diffusion equations. It is shown that progression of viral infection can be characterized by the viral replication number, time-dependent viral load, and the speed of infection spreading. These three characteristics are determined through the original model parameters including the rates of cell infection and of virus production in the infected cells. The clinical manifestations of viral infection, depending on tissue damage, correlate with the speed of infection spreading, while the infectivity of a respiratory infection depends on the viral load in the upper respiratory tract. Parameter determination from the experiments on Delta and Omicron variants allows the estimation of the infection spreading speed and viral load. Different variants of the SARS-CoV-2 infection are compared confirming that Omicron is more infectious and has less severe symptoms than Delta variant. Within the same variant, spreading speed (symptoms) correlates with viral load allowing prognosis of disease progression. 相似文献
999.
Steffen A. Föhrenbacher Mirjam J. Krahfuss Ludwig Zapf Dr. Alexandra Friedrich Dr. Nikolai V. Ignat'ev Prof. Dr. Maik Finze Prof. Dr. Udo Radius 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3504-3516
Fluoride abstraction from different types of transition metal fluoride complexes [LnMF] (M=Ti, Ni, Cu) by the Lewis acid tris(pentafluoroethyl)difluorophosphorane (C2F5)3PF2 to yield cationic transition metal complexes with the tris(pentafluoroethyl)trifluorophosphate counterion ( FAP anion, [(C2F5)3PF3]−) is reported. (C2F5)3PF2 reacted with trans-[Ni(iPr2Im)2(ArF)F] (iPr2Im=1,3-diisopropylimidazolin-2-ylidene; ArF=C6F5, 1 a ; 4-CF3-C6F4, 1 b ; 4-C6F5-C6F4, 1 c ) through fluoride transfer to form the complex salts trans-[Ni(iPr2Im)2(solv)(ArF)] FAP ( 2 a - c[solv] ; solv=Et2O, CH2Cl2, THF) depending on the reaction medium. In the presence of stronger Lewis bases such as carbenes or PPh3, solvent coordination was suppressed and the complexes trans-[Ni(iPr2Im)2(PPh3)(C6F5)] FAP ( trans -2 a[PPh3] ) and cis-[Ni(iPr2Im)2(Dipp2Im)(C6F5)] FAP ( cis -2 a[Dipp2Im] ) (Dipp2Im=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) were isolated. Fluoride abstraction from [(Dipp2Im)CuF] ( 3 ) in CH2Cl2 or 1,2-difluorobenzene led to the isolation of [{(Dipp2Im)Cu}2]2+2 FAP− ( 4 ). Subsequent reaction of 4 with PPh3 and different carbenes resulted in the complexes [(Dipp2Im)Cu(LB)] FAP ( 5 a – e , LB=Lewis base). In the presence of C6Me6, fluoride transfer afforded [(Dipp2Im)Cu(C6Me6)] FAP ( 5 f ), which serves as a source of [(Dipp2Im)Cu)]+. Fluoride abstraction of [Cp2TiF2] ( 7 ) resulted in the formation of dinuclear [FCp2Ti(μ-F)TiCp2F] FAP ( 8 ) (Cp=η5-C5H5) with one terminal fluoride ligand at each titanium atom and an additional bridging fluoride ligand. 相似文献
1000.
Irena S. Akhrem Dzhuletta V. Avetisyan Lyudmila V. Afanaseva Oleg I. Artyushin Nikolai D. Kagramanov Andrey L. Sigan 《Tetrahedron letters》2017,58(42):4014-4019
The one-pot, regioselective synthesis of branched diacid derivatives – diesters, dithioesters, diamides [YC(O)O(CH2)mC(Me)2OC(O)Y] and diketones of aromatic and heteroaromatic series, [ArCO(CH2)mC(Me)2C(O)Ar,) from available linear acyl halides, CnH2 n+1COCl (n = 7–9), CO (1 at) and various nucleophiles (YH = EtOH, CF3CH2OH, H(CF2)2CH2OH, thiophene, anisole, Et2NH, aniline, and morpholine) in the presence of the superelectrophilic complex, CBr4·2AlBr3 has been performed for the first time. This method provides access to new and promising groups of dicarboxylic acid derivatives and diketones containing quaternary carbon atom and remote functional groups. 相似文献