Structure and mechanical properties of the welded joints of large-diameter pipes

The structure and mechanical properties of the technological welded joints of large-diameter pipes of strength class K60 produced by two companies are studied. Along with standard mechanical properties (σ0.2, σu, δ, ψ), specific work of deformation a (tensile toughness) and true rupture strength Sf are estimated from an analysis of the stress-strain diagrams constructed in true coordinates. The mechanical behavior is found to be different for samples cut from different zones of a welded joint (central weld, heat-affected zone, and base metal). The mutual correlation between parameters a, S f, and impact toughness KCV is considered. © 2013 Pleiades Publishing, Ltd

Optical constatnts of yttrium-iron garnet single-crystal film strucrures

Light-attenuation spectra of yttrium–iron gar-net single-crystal film structures grown on a gallium–gadolinium garnet substrate by liquid-phase epitaxy from the undercooled solution in the melt have been studied and compared with those of bulk yttrium–iron garnet samples. The calculated optical constants are discussed tak-ing into account the influence of crystal field on the splitting of the energy states of iron ions in the film samples.

ВЛИЯНИЕ КОМПОНЕНТНОГО СОСТАВА МИЦЕЛЛЯРНОГО РАСТВОРА НА СПЕКТРАЛЬНЫЕ СВОЙСТВА И СОЛЮБИЛИЗАЦИЮ ПЛЮРОНИКОМ ПРОИЗВОДНОГО БОРДИФТОРИД-ДИПИРРОЛИЛМЕТЕНА

It has been shown by a spectral method that the efficiency of solubilization of a borondifluoride dipyrromethene derivative by Pluronic F-127 inmixed systems depends on the proportions of mass concentrations of the dye and Pluronic in an initial liquid solution. It has been established that the values of the Pluronic F-127 concentration, at which the micelles solubilizing the dye are efficiently formed, exceed 10 % (mass). The analysis of spectral characteristics of the solution of the “dye – Pluronic” adducts has shown that the dye under study exists in the Pluronic micelles in the highest degree of disaggregation manifesting the spectral characteristics of monomeric form.Спектральным методом показано, что эффективность солюбилизации плюроником F-127 производного бордифторид-дипирролилметена зависит от соотношения в смешанных системах массовых концентраций красителя и плюроника в исходном жидком растворе. Установлено, что характерные значения концентраций плюроника в растворе, при которых образуются мицеллы, солюбилизирующие краситель, превышают 10 мас.%. Анализ спектральных характеристик рас- творов аддуктов «краситель–плюроник» показал, что исследуемый краситель в мицеллах плюроника находится в наибольшей степени дезагрегации, проявляя спектральные характеристики мономерной формы.