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141.
Natalia Sh. Lebedeva Anatoly I. Vyugin Natalia A. Pavlycheva Elena V. Parfenyuk Olga I. Davidova 《Thermochimica Acta》2002,390(1-2):179-186
The heats of interactions of zinc(II)tetraphenylporphyrine with 30 types of neutral molecules in benzene and carbon tetrachloride were measured using the calorimetric titration method. The thermodynamic characteristics of complex formation were calculated. The satisfactory multiparameter correlation of thermodynamic stability of the molecular complexes formed with physicochemical properties of the neutral molecules (electron pair donor ability, volume, electronic and orientational polarization) was obtained. 相似文献
142.
Natalia A. Nikonorova Nikolai N. Smirnov Ricardo Diaz‐Calleja Alexander V. Yakimansky 《Journal of Polymer Science.Polymer Physics》2008,46(14):1488-1496
Local forms of molecular mobility of comb‐like random copolymethacrylates, containing side‐chain nonlinear optical chromophores and amyl‐ or octafluoroamyl‐groups, are studied. In the glassy state, two relaxation processes are found, which are due to reorientation of terminal polar groups (γ2‐process) and rotation of chromophore groups about their long axes (β‐process). For octafluoroamyl‐containing copolymers, the γ2‐process is superposition of the two molecular motions due to reorientation of terminal chromophore groups and ? CF2H groups. The intensity and relaxation times in the range of the γ2‐process depend on the chemical structure and concentration of chromophores in a copolymer. For the β‐process, the molecular mobility weakly depends on the chromophore structure, being mainly determined by the relative lengths of the rigid chromophore and flexible side chains. On the global spectrum of depolarization current it was observed the γ1‐process due to reorientation of (CH2)n spacers between chromophore groups and copolymer backbone. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1488–1496, 2008 相似文献
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Bogusław Buszewski Agnieszka Ulanowska Tomasz Ligor Natalia Denderz Anton Amann 《Biomedical chromatography : BMC》2009,23(5):551-556
In this study, 38 samples of expired air were collected and analyzed from 20 non‐smoking volunteers, four passive smokers and 14 smokers (21 women and 17 men). Measurements were carried out using solid‐phase microextraction (SPME) as an isolation and preconcentration technique. The determination and identification were accomplished by gas chromatography coupled with mass spectrometry (GC/MS). Our data showed that ca 32% of all identified compounds in the breath of healthy non‐smokers were saturated hydrocarbons. In the breath of smoking and passive smoking volunteers hydrocarbons were predominant, but also present were more exogenous analytes such as furan, acetonitrile and benzene than in the breath of non‐smokers. Acetonitrile, furan, 3‐methylfuran, 2,5‐dimethylfuran, 2‐butanone, octane and decane were identified in breath of smoking and passive smoking persons. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
145.
Anastasia S. Kozlenko Nadezhda I. Makarova Ilya V. Ozhogin Artem D. Pugachev Maria B. Lukyanova Irina A. Rostovtseva Gennady S. Borodkin Natalia V. Stankevich Anatoly V. Metelitsa Boris S. Lukyanov 《Mendeleev Communications》2021,31(3):403-406
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146.
Aldrich LN Lebois EP Lewis LM Nalywajko NT Niswender CM Weaver CD Conn PJ Lindsley CW 《Tetrahedron letters》2009,50(2):212-215
General, high-yielding MAOS protocols for the expedient synthesis of functionalized 3,6-disubstituted-[1,2,4]triazolo[4,3-b]pyridazines are described amenable to an iterative analog library synthesis strategy for the lead optimization of an M1 antagonist screening hit. Optimized compounds proved to be highly selective M1 antagonists. 相似文献
147.
Natalia Osipova 《Operations Research Letters》2008,36(3):372-376
We study the Processor Sharing queueing model with a hyper-exponential service time distribution and Poisson batch arrival process. In the case of the hyper-exponential service time distribution we find an analytical expression for the expected conditional response time function and obtain an alternative proof of its concavity with respect to the service time. 相似文献
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Bis-paddlewheel heterobimetallic complexes in which palladium(II) is connected to the rare-earth metals(III) [Pd(μ-OOCMe)4Ln(OH2)(μ,η2-OOCMe)]2 × 2HOOCMe (Ln = Nd, Sm, Eu, Yb and Tm) by four acetate bridges were synthesised by the reaction of Pd3(μ-OOCMe)6 with the LnIII acetates. The tetraacetate-bridged complexes were unexpectedly found to be readily transformed by the stoichiometric amount of pivalic acid into the mono-paddlewheel tetrapivalate-bridged analogues in which the paddlewheel structure [Pd(μ-OOCR)4Ln] maintains as established by X-ray crystallography. The role of the intra- and intermolecular H-bonding in these complexes is discussed. 相似文献
150.
A Novel Streptavidin–luciferase Fusion Protein: Preparation,Properties and Application in Hybridization Analysis of DNA
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Daria V. Smirnova Maya Y. Rubtsova Vitaly G. Grigorenko Natalia N. Ugarova 《Photochemistry and photobiology》2017,93(2):541-547
A streptavidin–luciferase fusion protein comprising the thermostable mutant form of firefly luciferase Luciola mingrelica and minimal core streptavidin was constructed. The streptavidin–luciferase fusion was mainly produced in a tetrameric form with high luciferase and biotin‐binding activities. It was shown that fusion has the same Km values for ATP and luciferin and the bioluminescence spectra as initial luciferase. The linear dependence of the bioluminescence signal on the content of the fusion was observed within the range of 10?18–10?13 mol per well. Successful application of obtained fusion in a biospecific bioluminescence assay based on biotin–streptavidin interactions was demonstrated by the example of a specific DNA hybridization analysis. A DNA hybridization analysis for Escherichia coli cells identification was developed using unique for these cells gadB fragment encoding glutamate decarboxylase. The amplified biotinylated GadB fragments were hybridized with the immobilized oligonucleotide probes; then, the biotin in the DNA duplexes was detected using the streptavidin–luciferase fusion protein. To reach the high sensitivity of the assay, we optimized the conditions of the assay. It was shown that the use of Pluronic for plate modification resulted in a significant reduction in the DNA detection limit which finally was 0.4 ng per well. 相似文献