Hopping Conduction in Disordered Carbon Nanotubes

We report electrical transport measurements on individual disordered carbon nanotubes, grown catalytically in a nanoporous anodic aluminum oxide template. In both as-grown and annealed types of nanotubes, the low-field conductance shows as exp[-(T_{0}/T)^{1/2}] dependence on temperature T, suggesting that hopping conduction is the dominant transport mechanism, albeit with different disorder-related coefficients T_{0}. The field dependence of low-temperature conductance behaves an exp[-(xi_{0}/xi)^{1/2}] with high electric field xi at sufficiently low T. Finally, both annealed and unannealed nanotubes exhibit weak positive magnetoresistance at low T = 1.7 K. Comparison with theory indicates that our data are best explained by Coulomb-gap variable range hopping conduction and permits the extraction of disorder-dependent localization length and dielectric constant.Comment: 10 pages, 5 figure

INVESTIGATION OF MECHANICAL PROPERTIESOF MR MATERIAL BY OPTOELECTRONIC SENSOR

The article represents the technique of measuring the deformation of the wire material MR (metallic rubber) in order to know it’s mechanical properties. Investigation of those properties will allow obtaining the new techniques of wire spiraling and pressing, using modern mathematical simulation techniques (ANSYS and LS-DYNA)

CALCULATION-EXPERIMENTAL EVALUATION OF CARRYING CAPACITY OF A BLADE OF AXIAL TURBOMACHINE

The article describes the approach to verifying the deformation CAE model of the blade. The papers presents a comparative analysis of the results of computational research and experiment The effect of rotating the blade on its carrying capacity is described

THE MACHINE FOR AUTOMATED PRODUCTION OF BLANKS MATERIAL MR

The article describes the design of the machine for automated production of blanks from material MR (metallic rubber). In the future, creation of this machine will allow researching the effect of blanks structure upon the properties offinished products from the material MR

РАСЧЕТ РЕЗОНАНСНЫХ ЧАСТОТ КОЛЕБАНИЙ РАБОЧИХ КОЛЕС ВРД С ИСПОЛЬЗОВАНИЕМ ВОЛНОВЫХ КОНЕЧНЫХ ЭЛЕМЕНТОВ

 The highly efficient algorithm for finding the resonance frequencies of rotating blade disks from gas turbine engines was developed. The algorithm based on use of interpolation function at the frequency domain for stresses and material properties. The algorithm don't use resonance diagram to find resonance frequencies of blade disks. The developed algorithm is implemented as a computer programming language Fortran. The resonance frequencies of model blade disk were explored.  Для исследований резонансных частот вращения рабочих колес турбомашин с примене­нием волновых конечных элементов разработан высокоэффективный алгоритм, не требую­щий построения резонансной диаграммы колеса. Алгоритм основан на введении интерпо­лирующих функций в частотной области для механических характеристик материалов и статических напряжений от действия поля центробежных сил и неравномерного нагрева, в сечениях конструкции. Разработанный алгоритм реализован в виде вычислительной про­граммы на языке программирования Фортран. Проведены сравнительные расчетные иссле­дования резонансных частот колебаний рабочего колеса