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971.
Physics of the Solid State - The thermodynamic properties and phase transitions in a two-dimensional strongly diluted threevertex antiferromagnetic Potts model on a triangular lattice have been... 相似文献
972.
A. Ya. Gerchikov G. M. Sharipova I. V. Safarova M. V. Sakhibgareeva S. I. Spivak 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(6):1010-1014
The kinetics and mechanism of the antioxidative action of С60 fullerene are studied via highly sensitive manometry and kinetic spectrophotometry, based on the example of a model reaction of the initiated oxidation of 1,4-dioxane. The adequacy of the proposed mechanism according to the experimental data is analyzed by means of mathematical modeling. The mechanism behind the inhibiting process is found to be a multi-center radical reaction. The rate constants of the elementary stages are determined. 相似文献
973.
The program for calculating the fields of characteristic physical quantities in a twodimensional diffusion-induced flow over an impermeable strip immersed in a continuously stratified fluid at rest is developed on the basis of the fundamental system of equations. The flow patterns are presented with a high spatial resolution, the complicated structure of compensation flows near the strip edges is studied, and the ranges of applicability of the previously obtained analytical (asymptotic) solutions are determined. The calculated results are in agreement with the data of high-resolution shadow visualization of streaky structures adjoining the edges of the fixed strip immersed in a stratified fluid. 相似文献
974.
Hsiu‐Fu Hsu Corresponding author Shih‐Jay Chien Hsiu‐Hui Chen Chien‐Hsing Chen Li‐Ya Huang Chung‐Hao Kuo 《Liquid crystals》2013,40(6):683-689
Liquid crystalline α,α′‐bis(4‐alkoxyphenylethynyl)oligothiophenes (bi‐ and ter‐thiophene) have been synthesized and their mesogenic behaviour and optical properties investigated. They all exhibited a nematic mesophase, and compounds with long alkoxy chains also showed lamellar phases. Increasing the number of thiophene units increased both the transition temperatures and the mesophase ranges. As for their optical properties, incorporating more thiophene units results in red‐shifted absorption and emission spectra, slightly enhanced quantum efficiency, and a larger Stoke's shift. Most importantly, in terms of the absorption and emission maxima, the incorporation of one 4‐alkoxyphenylethynyl moiety was found to be equivalent to adding one thiophene ring. 相似文献
975.
As the hardware of FLIM technique becomes mature, the most important criterion for FLIM application is the correct interpretation of its data. In this research, first of all, a more orthogonal phasor approach, called as Modified Phasor Approach (MPA), is put forward. It is a way to calculate the lifetime of the complex fluorescent process, and a rule to measure how much the fluorescence process deviates from single exponential decay. Secondly, MPA is used to analysis the time-resolved fluorescence processes of the transfected CHO-K1 Cell lines expressing adenosine receptor A1R tagged by CYP and YFP, measured in the channel of the acceptor. The image of the fluorescence lifetime and the multiplication of the fluorescence lifetime and deviation from single exponential decay reveal the details of the Homo-FRET. In one word, MPA provides the physical meaning in its whole modified phasor space, and broadens the way for the application of the fluorescence lifetime imaging. 相似文献
976.
A. Ya. Fridman A. Yu. Tsivadze E. M. Morozova N. P. Sokolova A. A. Shiryaev G. A. Petukhova A. M. Voloshchuk I. I. Bardyshev A. M. Gorbunov I. Ya. Polyakova A. K. Novikov V. N. Titova A. A. Yavich N. V. Petrova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(12):2453-2458
A material with porous structures formed by jointed aza- and oxa-aza-crowns with peripheral OHgroups is synthesized on the basis of cellulose fabric and PVC transformed into hydroxyethylcyclam. Mesopores are mainly observed on the fiber surface. The specific surface of the material is 6 m2/g; the volume of free space is 0.112 cm3/g. Assuming the internal pores have a disk-like shape, their width is estimated at 2 nm. The material sorbs vapors of aliphatic and aromatic hydrocarbons, alcohols, aldehydes, ketones, amines, amides, nitriles, and sulfoxides. It also swells to a limited degree in organic solvents. When sulfuric acid or sodium hydroxide is sorbed in the pores, compounds of them with H+- and OH–-conducting systems of hydrogen bonds are formed. 相似文献
977.
V. Ya. Borkhodoev 《Journal of Analytical Chemistry》2014,69(11):1041-1046
Blank experiment in X-ray fluorescence analysis is actually a measurement of the background at the analytical line of an element to be determined. Numerous factors affecting the appearance and registration of the background signal are responsible for its normal distribution. In this work, the possibility of using real samples with low analyte concentrations as blank samples is substantiated. A criterion for the assessment of the correctness of different equations for calculating the limit of detection is proposed. An expression for the calculation of the limit of detection using a one-sided confidence interval of the distribution of analytical signal is derived. An algorithm for the assessment of the limit of detection is proposed. 相似文献
978.
979.
Jiancong Du Suhui Deng Shangguo Hou Lingling Qiao Jianfang Chen Qing Huang Chunhai Fan Ya Cheng Yun Zhao 《中国光学快报(英文版)》2014,12(4):41101-38
DNA tetrahedral nanostructures are considered to be uew nanocarriers because they can be precisely controlled and hold excellent penetration ability to the cellular membrane. Although the DNA tetrahedral nanostructure is extensively studied in biology and medicine, its behavior in the cells with nanoscale resolution is not understood clearly. In this letter, we demonstrate superrcsolution fluorescence imaging of the distribution of DNA tetrahedral nanostructures in the cell with a simulated emission depletion (STED) microscope, which is built based on a conventional eonfocal microscope and can t)rovide a resolution of 70 nm. 相似文献
980.
V. F. Ivanov D. A. Gordon I. A. Shilova V. A. Lesnichaya A. I. Mikhailov E. Ya. Misochko 《Russian Journal of Applied Chemistry》2016,89(8):1292-1295
New composite lignocellulose materials were prepared using modified lignin and nanocellulose. The materials were studied by elemental and thermal gravimetric analysis, and their tensile tests were performed. The results obtained show that addition of nanocellulose to modified lignin makes possible its use as filler in paper production. 相似文献