Gland packings with pliant casings

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, pp. 9–10, March, 1989.     

Induction of substances with thymosin-like activity and the potentiation of interferonogenesis in the mechanism of prodigiozan inhibition of 3-methylcholanthrene-induced blastomogenesis

It is shown that prodigiosan is an inductor of synthesis of the substances with the thymosin-like activity. The suggestion about inhibition of 3-methylcholanthrene-induced blastomogenesis by prodigiosan which is mediated by the substances with the thymosin-like activity and interferon is discussed. We present the hypothetical diagram of the development of the above mentioned mechanism. The significance of the obtained findings for elaboration of the immunotherapy is discussed.     

Theory of the Structure of Coherent Boundaries in ZrO<Subscript>2</Subscript> Nanoparticles

A general algorithm is proposed for constructing coherent boundaries. This algorithm is based on the interrelation between the spatial coherence of structural fragments in nanoparticles and the geometric connection in the corresponding associated bundle. A local approach is used to describe the structure of coherent boundaries in zirconia nanoparticles. The inference is made that the models of structures thus obtained should be preferred over the models constructed in terms of the theory of coincident site lattice.Original Russian Text Copyright © 2005 by Fizika i Khimiya Stekla, Shevchenko, Samoilovich, Talis, Madison.     

The wave theory of a plane lens made from a negative material

A plane lens made from a negative material (metamaterial) is considered. The wave theory that was developed earlier is generalized to the case when the wave-energy loss in the lens and in the ambient medium is taken into account. The dimensions of the spot that is formed in the field-focusing region in the presence of loss, instead of the focal point existing in the absence of loss, are analytically estimated. It is shown that the dimensions of the spot are related to the loss parameters in the media and to the lens’ thickness. The dependence of the dimensions of the spot on the field frequency (and wavelength) is due only to the frequency dispersion of the loss parameters. The dimensions of the spot formed owing to the finite dimensions of the lens are estimated.     

Selecting gunning materials for the working lining of intermediate ladles at the MMK corporation

Production has been organized of new grades of gunning materials at the Magnesite Gunning Material Corporation (previously the Magnesite Intokast Satka Corporation), which is part of the Magnesite Group holding, and these materials are used to form the working layer of lining in intermediate MNLZ ladles. Effective use has been made of a novel special technology for preparing the gunning materials. The method implies organizing the relation between the refractory maker and the users as regards modifying the quality of the gunning materials in accordance with changes in the production parameters and the amount of steel. The new materials completely match the technological specifications of MNLZ Corporation at MMK and provide a considerable reduction in the costs of preparing the intermediate ladles.     

Isotactic and syndiotactic polypropylene/multi-wall carbon nanotube composites: synthesis and properties

Isotactic polypropylene (iPP) and syndiotactic polypropylene (sPP) nanocomposites containing 0.1–3.5 wt.% multi-wall carbon nanotubes (MWCNTs) have been synthesized via in situ polymerization method with the use of C₂- and C_s- symmetry zirconocenes activated by methylaluminoxane (MAO) in liquid propylene medium. Fracture morphology studies by SEM reveal different MWCNT dispersion efficiency in various polymer matrices, which arises from the catalytic peculiarities of the composite synthesis. Considerable Young’s modulus enhancement of iPP and sPP (25–66%) takes place even at low MWCNT loadings (below 0.5 wt.%). The obtained nanocomposites can find use as efficient electromagnetic shielding materials and microwave absorbing filters due to relatively low permittivity values and considerable dielectric losses in microwave range. Calorimetry data demonstrate that MWCNTs exert evident influence as nucleating agents causing the rise of iPP and sPP crystallization temperature. Considerable retardation effect on iPP thermal oxidative degradation has been observed: the temperature of maximal weight loss rate rises by ~52 °C upon incorporating only 1.4 wt.% MWCNTs.