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91.
We have proposed a tested in tissue phantoms and in vivo a novel sensor based on optical coherence tomography (OCT) for noninvasive and continuous monitoring of blood glucose concentration. OCT images were obtained from pig and rabbit skin before and after glucose administration. Slopes of OCT signals decreased substantially (~40% in tissues in vivo) and linearly with the increase of blood glucose concentration from 4 to 30 mM, typical for normal and diabetic subjects. Phantom studies demonstrated 1% accuracy of scattering-coefficient measurement. Our theoretical and experimental studies suggest that glucose concentration can potentially be measured noninvasively with high sensitivity and accuracy with OCT systems.  相似文献   
92.
Silylation of 1,1-dialkoxy-2-propanones with trimethyl- and tert-butyldimethylsilyl chlorides and trifluoromethanesulfonates in the presence of triethylamine and/or 1,8-diazabicyclo[5.4.0]undec-7-ene in various solvents leads to 2-trialkylsiloxypropenal acetals in up to 60% yield.  相似文献   
93.
A model kinetic equation approximating the Boltzmann equation with a linearized collision integral is constructed to describe rarefied gas flows at moderate and low Knudsen numbers. The kinetic model describes gas flows with a power-law intermolecular interaction potential and involves five relaxation parameters. The structure of a shock wave is computed, and the results are compared with an experiment for argon.  相似文献   
94.
Kinetics and Catalysis - An operando kinetic study was made of the Mizoroki–Heck reaction with low-reactive aryl chlorides using the most practically attractive “ligand-free”...  相似文献   
95.
The nucleophilic addition of 2-phenylethylphosphine, bis(2-phenylethyl)phosphine oxide, and bis(2-phenylpropyl)phosphine oxide to 3-thiolene 1,1-dioxide catalyzed by the KOH-DMSO system leads to bis(3-thioanil) (2-phenylethyl)phosphine oxide, bis(2-phenylethyl) (3-thianil)phosphine oxide, and bis(2-phenylpropyl) (3-thioanil)phosphine oxide, respectively.Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences, 664033 Irkutsk. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1195–1198, September, 1998.  相似文献   
96.
For rarefied gas flows at moderate and low Knudsen numbers, model equations are derived that approximate the Boltzmann equation with a linearized collision integral. The new kinetic models generalize and refine the S-model kinetic equation.  相似文献   
97.
98.
1-[1-Bromo-2-benzoyl(2-thenoyl)vinyl]-1,1-dimethylhydrazinium bromides were synthesized by the reactions of 1-aroyl-2-bromoacetylenes withN,N-dimethylhydrazine in acetonitrile at 20°C. The structure of 1-(2-benzoyl-1-bromovinyl)-1,1-dimethylhydrazinium bromide was established by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1536–1538, August, 1999.  相似文献   
99.
This paper gives a new formula for the plethysm of power-sum symmetric functions and Schur symmetric functions with one part. The form of the main result is that for b,
where the sum is over semistandard tableaux T of weight a b , is a root of unity, and maj(T) is a major index like statistic on semistandard tableaux.An Sb-representation, denoted S,b, is defined. In the special case when b, S,b is the Specht module corresponding to . It is shown that the character of S,b on elements of cycle type is
where the sum is over semistandard tableaux T of shape and weight ab. Moreover, the eigenvalues of the action of an element of cycle type acting on S,b are { }. This generalizes J. Stembridge's result [11] on the eigenvalues of elements of the symmetric group acting on the Specht modules.  相似文献   
100.
The interaction of N-(1-aryl-2,2,2-trichloroethyl)amides of arenesulfonic acids with secondary amines or their salts in the presence of inorganic bases involves the formation of chloroaziridine intermediates. Depending upon the solvent and reagent ratio, the reaction results in N-[1-dialkylamino-2-chloro-2-arylethylidene]-, N-[2-dialkylamino-1-chloro-2-arylethylidene]-, N-[1,2-bis(dialkylamino)-2-arylethylidene]-, and N-(1,2-dioxo-2-arylethene)amides of arenesulfonic acids.  相似文献   
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