Convergent Star Product Algebras on ‘ax+b’

We define nontempered (exponential growth) function spaces on the Lie group ax+b which are stable under some left-invariant (convergent) star product. The techniques used to achieved the latter come from symmetric spaces geometry and star representation theory.     

Thermal coefficient of linear expansion of non-crystalline chalcogenides in the As-S-Se-Te-I system

The object of the paper is an investigation of the glasses of the (As₂S₃)_x(AsSe_0.5Te_0.5I)_100-x. type for 65≤;x≤;95, using methods of thermomechanical analysis. Values of the thermal coefficients of linear expansion in solid and visco-plastic phase were determined. it was shown that introducing arsenic-sulfide in glass-matrix AsChI, i.e. (AsSe_0.5Te_0.5I), leads to an increasing stability of these glasses. The characteristic temperatures of softening Tg and the temperature of the beginning of deformation t_w increase by increasing content of As₂S₃. The analytical forms of dependence of four significant physical values α_g, α_l, Tg, Tw, as a function of As₂S₃ content in the structure of glasses were fitted. This revised version was published online in July 2006 with corrections to the Cover Date.     

JD树脂刻蚀及涂层的XPS研究

ＪＤ光学树脂表面刻蚀过程的ＸＰＳ研究表明，引进树脂遥ＣＯＨ，Ｃ＝Ｏ，Ｃ－ＳＯ３Ｈ，ＣＯＯＨ等基因随刻蚀温度的提高或时间的延长而增加，对其相对含量进行了计算，固化后的耐磨涂层具有ＳｉＯ２结构，ＪＤ板材的最佳刻蚀条件为２０℃，２０ｍｉｎ。     

Sorption of water vapor on cation-substituted vermiculite

Deformations of Na, Ca, and Ba vermiculites upon sorption of water vapor have been determined by a dilatometric method. Sequential stages in the hydration of interlayer exchange cations have been identified. The experimental results have been compared with data obtained in studies using adsorptive, calorimetric, and x-ray methods.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Institute of Colloid Chemistry and the Chemistry of Water, Academy of Sciences of the Ukraine, Kiev. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 34–39, January, 1992.     

Enhancement of the light-scattering ability of coatings by using hollow pigments

The light-scattering properties of coatings based on monodisperse polymeric spheres of two different diameters (ca 0.5 and 1 m) were evaluated from reflectance measurements as a function of the wavelength from 400 to 700 nm. Some of these plastic pigments were hollow and it was noted that these particles gave coatings with a greater light-scattering ability than coatings based on solid particles of a similar size. It was possible to estimate the contribution of the internal pores to the scattering ability of the coating layers by saturating the layers with an oil of a refractive index similar to that of the polymeric pigment particles. A simple model accounting for the scattering provided by the internal pores of the hollow particles is suggested. The agreement between the experimental results and the prediction of the model is fair. It was noted that the light scattering coefficient of the coatings increased when the external diameter of their constituent hollow particles increased from ca 0.5 to 1 m.     

Deformation calorimetry of polyurethane block-copolymers

A thermodynamic analysis of the uniaxial stretching of polyurethanes of various compositions and mechanical histories was carried out by using deformation calorimetry. The initial small strain deformations were found to result from the volume elasticity of the hard phase. The intramolecular energy contributions of the soft blocks were estimated. The hard block contributions were shown to depend on their content and on the degree of sample stretching. The predominant role of the soft component is proved to be manifested only in softened samples with a hard block content not exceeding 30%. The thermodynamics of the softening and hysteresis phenomena were studied. The dependence of the deformation mechanism on the hard block content and mechanical history is discussed.The authors express their thanks to Dr. A. R. Korigodsky and Dr. M. P. Letunovsky for the PU samples.     

Electron density distribution in potassium bis -(carbonato)cuprate(II)

The electron density distribution in potassiumbis-(carbonato)cuprate(II) has been analyzed using x-ray diffraction data from an earlier structure determination. While the copper-ligand geometry is close to square planar the deformation density near the metal is strongly asymmetric. There are local maxima near the copper atom along the line of the Cu-K vectors. These resemble features found in corresponding regions in normal length metal-metal bonds. The observation is consistent with the long range nature of the Coulomb potential associated with the potassium ion.     

RESEARCH ANNOUNCEMENTS ON “DPK: DEEP NEURAL NETWORK APPROXIMATION OF THE FIRST PIOLA-KIRCHHOFF STRESS”

1 Introduction and Main Results Consider the first Piola-Kirchhoff stress P defined as[1]P(F)=?W(F)/?F,(1.1)where F and W refer to the deformation tensor and strain energy density.Due to the principle of material frame-indifference and the material symmetry,two important constraints should be satisfied by these relations[1].     

Hydrodynamic thickness and deformational properties of adsorption layers of poly(ethyleneoxides)

From the measurements of surface potentials of quartz capillaries before and after adsorption of poly(ethylene oxides) (PEO) of various molecular mass, an assessment of the equilibrium hydrodynamic thickness of the adsorption layers has been obtained. The results have been compared with those of independent measurements of . The flow of the polymer solution under increasing pressure drops at the ends of a capillary, which causes the corresponding shear stress () on the surface of adsorbed PEO layers, results in the deformation of the latter, which manifests itself in decreasing 5. The values decrease by several times when the shear stress rises to 2×10₂ N m^–2. Such values of have been obtained using thin capillaries (r = 5÷6 mm) and by application of the capillary electrokinetic method with pressure drops up to 5÷6 MPa.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 31–37, January, 1994.