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1.
The phase transitions and phase state of hydroxypropylcellulose mixtures with ethanol and acetic acid under static conditions and in the shear field have been studied by the turbidity-point method and polarization microscopy with the use of a polarization-photoelectric setup and a modified plastoviscometer. The deformation of solutions leads to a decrease in the temperature of mesomorphic phase formation and to a change in the type of liquid crystals from cholesteric to nematic. 相似文献
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Phase transitions in the systems cyanoethyl cellulose-DMF, cyanoethyl cellulose-DMAA, and cyanoethyl cellulose-(trifluoroacetic acid + methylene chloride) were studied by means of the cloud-point and polarization microscopy techniques, as well as with a photoelectric polarization unit and a modified plasticorder. It was shown that the LC phase appears at higher concentrations and lower temperatures as the polarity of solvent molecules increases. The shear deformation of cyanoethyl cellulose solutions in DMF and DMAA results in the expansion of the temperature-concentration region of existence of the LC phase. The effect of shear field on phase transitions in cyanoethyl cellulose solutions is nonmonotonic in character. 相似文献
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Skorik Yu. A. Neudachina L. K. Osintsev A. V. Yatluk Yu. G. Vshivkov A. A. Osintseva E. V. 《Russian Journal of Organic Chemistry》2002,38(3):385-389
4-[4-Bis(2-carboxyethyl)aminophenylazo]benzenesulfonic acid and 4-[2-bis(2-carboxyethyl)amino-4,5-dimethylphenylazo]benzenesulfonic acid were synthesized for the first time by azo coupling of diazosulfanilic acid with N,N-bis(2-carboxyethyl)aniline and N,N-bis(2-carboxyethyl)-3,4-xylidine, respectively. The acid ionization constants of the products were determined, their electron absorption spectra were measured, and schemes of acid-base equilibria in aqueous solution were proposed. 相似文献
4.
Skorik Yu. A. Romanenko G. V. Neudachina L. K. Vshivkov A. A. 《Russian Journal of Coordination Chemistry》2001,27(11):796-802
Crystals of [Cu(o-Andp)(H2O)2] · 2H2O (where o-Andp2–is -anisidine-N,N-di-3-propionate) were synthesized and studied using X-ray diffraction analysis. The crystals are triclinic: a= 12.063(1) Å, b= 12.483(3) Å, c= 13.586(2) Å, = 91.29(1)°, = 111.67(1)°, = 104.00(1)°, V= 1830.5(5) Å3, space group P
, Z= 2, and R= 0.0528 for 5965 reflections with I2(I). The two crystallographically independent complexes are isostructural. The tetragonal–bipyramidal coordination of copper(III) involves three O atoms, the N atom of the tetradentate ligand o-Andp2–, and two O atoms from water. The aminodipropionate group of the ligand (average Cu–O 1.939 Å and Cu–N 2.051 Å) and one of the coordinated water molecules (Cu–O(w) 1.991 Å) lie in the equatorial plane. The second water molecule (Cu–O(w) 2.32 Å) and the methoxy O atom of o-Andp2–(Cu–O 2.37 Å) are in the apical positions of the bipyramid. 相似文献
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Phase transitions, structures, and rheological properties of hydroxypropyl cellulose–ethylene glycol and ethyl cellulose–dimethylformamide systems in the presence and in the absence of a magnetic field have been studied. The application of the magnetic-field results in increases in viscosity and supramolecular particle size in solutions of cellulose ethers. Concentration dependences of viscosity and particle size are described by curves with maxima. 相似文献
7.
S. A. Vshivkov L. V. Adamova G. A. Galyas 《Russian Journal of Applied Chemistry》2010,83(7):1196-1201
Differential scanning calorimetry, X-ray diffraction analysis, polarization microscopy, methods of cloud points and static
sorption, and a polarization-photoelectric installation were used to make a thermodynamic analysis of systems constituted
by hydroxypropylcellulose, poly(ethylene glycols), and water. The thermodynamic parameters obtained were correlated with phase
diagrams of these systems. 相似文献
8.
V. K. Kedrinskii V. A. Vshivkov G. G. Lazareva 《Journal of Applied Mechanics and Technical Physics》2005,46(5):652-657
The structure and dynamics of the wave field generated by a bubble system in the form of an axial bubble cylinder (cord) excited by a plane shock wave propagating along the axis in an axisymmetric shock tube are numerically examined. It is shown that consecutive excitation of oscillations of the bubble zone results in formation of a quasi-steady shock wave in the cord and in the ambient liquid. Results of the numerical analysis of the maximum amplitude of the resulting wave as a function of problems parameters are described.__________Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 5, pp. 46–52, September–October, 2005. 相似文献
9.
The effect of a magnetic field on the viscosity of magnetorheological poly(ethylene glycol)-aerosil-iron nanoparticle and poly(dimethylsiloxane)-aerosil-iron nanoparticle suspensions is studied. The magnetic field leads to an increase in the viscosity of the suspensions by a factor of 20–300. The concentration dependence of the effect of magnetic field on the viscosity of the systems is described by a curve with a maximum. The dependences of viscosity on shear rate upon loading and unloading do not coincide, thus indicating the relaxation character of the flow process. 相似文献
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