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41.
3,4-Dihydrocarbazol-(2H)-1-ones are transformed by boiling pyridine hydrochloride into corresponding carbazoles. 相似文献
42.
Emile Rouvier Raphaël Pastor Jean Musso Aim Cambon 《Magnetic resonance in chemistry : MRC》1974,6(12):640-643
In this paper we report the conformational analysis of several di- or trisubstituted ethanes substituted by the following groups: N-dialkly, thioalkyl, alkoxy, N-pyrrolidino, N-benzyl, nitrile or carbomethoxy. Spectra were calculated by a method based on chemical shifts. Relative stabilities of rotamers were discussed in relation to structural parameters (geometrical and electronic). 相似文献
43.
44.
1-Amino-2-dimethylamino-ethane and 1-amino-3-dimethylamino-propane react with o-methoxycarbonylphenyl isothiocyanate (I) to yield the corresponding 3-(ω-dimethylaminoalkyl)-2-thiono-1,2,3,4-tetrahydroquinazolin-4-ones (V). The tertiary amino group of V is quaternized to the corresponding ammonio derivative VI when treated with methyl iodide in methanol. 相似文献
45.
Emile Cherbuliez B. Willhalm O. Espejo S. Jaccard J. Rabinowitz 《Helvetica chimica acta》1967,50(5):1440-1452
o-Methoxycarbonyl-phenylisothiocyanate V and primary alkylamines (R″? NH2) reacted in the appropriate medium yield the corresponding 2-mercapto-3-alkyl-3, 4-dihydro-quinazolinone-4 derivatives VI (the ? NH2 group is thiocarbamoylated by the ? N?C?S group and then acylated in an intramolecular reaction by the ? COOCH3 group with elimination of CH3OH). 相似文献
46.
Emile Cherbuliez S. Jaccard R. Mouzenidou J. Rabinowitz 《Helvetica chimica acta》1966,49(6):1950-1951
4-Trimethylammoniobutyl hydrogensulfate, heated at 185°C under reduced pressure, yields 4-trimethylammoniobutylsulfuric monoester. The rate of scission of this ester in alkaline medium grows with the concentration of the OH? ions. 相似文献
47.
Sunil Kumar Surath Ghosh Bessem Samet Emile Franc Doungmo Goufo 《Mathematical Methods in the Applied Sciences》2020,43(9):6062-6080
The heat equation is parabolic partial differential equation and occurs in the characterization of diffusion progress. In the present work, a new fractional operator based on the Rabotnov fractional-exponential kernel is considered. Next, we conferred some fascinating and original properties of nominated new fractional derivative with some integral transform operators where all results are significant. The fundamental target of the proposed work is to solve the multidimensional heat equations of arbitrary order by using analytical approach homotopy perturbation transform method and residual power series method, where new fractional operator has been taken in new Yang-Abdel-Aty-Cattani (YAC) sense. The obtained results indicate that solution converges to the original solution in language of generalized Mittag-Leffler function. Three numerical examples are discussed to draw an effective attention to reveal the proficiency and adaptability of the recommended methods on new YAC operator. 相似文献
48.
Making use of the traditional Caputo derivative and the newly introduced Caputo-Fabrizio derivative with fractional order and no singular kernel, we extent the nonlinear Kaup-Kupershmidt to the span of fractional calculus. In the analysis, different methods of fixed-point theorem together with the concept of piccard L-stability are used, allowing us to present the existence and uniqueness of the exact solution to models with both versions of derivatives. Finally, we present techniques to perform some numerical simulations for both non-linear models and graphical simulations are provided for values of the order α = 1.00; 0.90. Solutions are shown to behave similarly to the standard well-known traveling wave solution of Kaup-Kupershmidt equation. 相似文献
49.
Emile Durand 《International Journal of Theoretical Physics》1975,14(6):417-422
The Corben-Schwinger theory gives imaginary values of the energy, forS 3 2 =1 states, in very intensive magnetic fields. The theory proposed by the author, which is most satisfactory in the nonrelativistic approximation, does not have this defect forS 3 2 =1 states, but it appears forS 3 2 =0 states. 相似文献
50.
S Shah S Lee JY Verkhoturov S Tuleuova N Schweikert EA Ramanculov E Revzin A 《Langmuir : the ACS journal of surfaces and colloids》2008,24(13):6837-6844
This paper describes a novel approach of controlling cell-surface interactions through an electrochemical "switching" of biointerfacial properties of optically transparent microelectrodes. The indium tin oxide (ITO) microelectrodes, fabricated on glass substrates, were modified with poly(ethylene glycol) (PEG) silane to make glass and ITO regions resistant to protein and cell adhesion. Cyclic voltammetry, with potassium ferricyanide serving as a redox reporter molecule, was used to monitor electron transfer across the electrolyte-ITO interface. PEG silane modification of ITO correlated with diminished electron transfer, judged by the disappearance of ferricyanide redox activity. Importantly, application of reductive potential (-1.4 V vs Ag/AgCl reference) corresponded with reappearance of typical ferricyanide redox peaks, thus pointing to desorption of an insulating PEG silane layer. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) characterization of the silanized ITO surfaces after electrical stimulation indicated complete removal of the silane layer. Significantly, electrical stimulation allowed to "switch" chosen electrodes from nonfouling to protein-adhesive while leaving other ITO and glass regions protected by a nonfouling PEG silane layer. The spatial and temporal control of biointerfacial properties afforded by our approach was utilized to micropattern proteins and cells and to construct micropatterned co-cultures. In the future, control of the biointerfacial properties afforded by this novel approach may allow the organization of multiple cell types into precise geometric configurations in order to create better in vitro mimics of cellular complexity of the native tissues. 相似文献