The application of an assisting gas plasma generator for low-temperature magnetron sputtering of Ti-C-Mo-S antifriction coatings on titanium alloys

The positive effect of assisting influence of high-density gas plasma formed by an independent plasma generator PINK on mechanical and tribological characteristics of Ti-C-Mo-S magnetron coating on titanium alloys at lowered to 350°С temperature of coating regardless of alloy structural condition was revealed by methods of calotest, nanorecognition, scratch testing and frictional material tests. The coating formed by means of a combined magnetron plasma method reduces titanium alloys friction coefficient in multiple times and increases wear resistance by two orders of magnitude. At the same time the mechanical properties of ultra-fine-grained titanium alloys obtained by nanostructuring do not deteriorate

Crystallographic parameters of compounds and solid solutions in binary systems Cu-Pt and Ga-Pt

The study establishes that the packing index in compounds of the system Cu-Pt is close to the value 0.74 against a slight deviation from the Zen law of atomic volumes. The compounds in the system Ga-Pt have the highest values of the packing index in the range of the equiatomic composition, which greatly exceed ψ for close-packed structures based on FCC and HCP lattices for compounds made of the same kind of atoms. A correlation between singular points on the phase diagram of the system Ga-Pt and high values of the packing index in compounds is established

Properties of resistive hydrogen sensors as a function of additives of 3d-metals introduced in the volume of thin nanocrystalline SnO2 films

Analysis of the results of studying electrical and gas sensitive characteristics of the molecular hydrogen sensors based on thin nanocrystalline SnO2 films coated with dispersed Au layers and containing Au+Ni and Au+Co impurities in the bulk showed that the characteristics of these sensors are more stable under the prolonged exposure to hydrogen in comparison with Au/SnO2:Sb, Au films modified only with gold. It has been found that introduction of the nickel and cobalt additives increases the band bending at the grain boundaries of tin dioxide already in freshly prepared samples, which indicates an increase in the density Ni of the chemisorbed oxygen. It is important that during testing, the band bending eφs at the grain boundaries of tin dioxide additionally slightly increases. It can be assumed that during crystallization of films under thermal annealing, the 3d-metal atoms in the SnO2 volume partially segregate on the surface of microcrystals and form bonds with lattice oxygen, the superstoichiometric tin atoms are formed, and the density Ni increases. If the bonds of oxygen with nickel and cobalt are stronger than those with tin, then, under the prolonged tests, atomic hydrogen will be oxidized not by lattice oxygen, but mainly by the chemisorbed one. In this case, stability of the sensors’ characteristics increases

Binary phase diagrams based on elements VIIIA and IB periods of the D. I. Mendeleev's table and features of crystallographic parameters

The data obtained as a result of the analysis of crystallogeometric parameters and the structure of state diagrams of binary systems from elements VIIIA and IB periods of the D. I. Mendeleev's table are presented. It is shown that the classification of the evolution of phase diagrams of binary systems by types, proposed by T. A. Lebedev, correlates with features of concentration dependences of the deviation of atomic volumes in solid solutions from Zen law

Steroid-refractory hand eczema: treatment experience

Hand eczema is a common multi-etiological disease manifested by evolutionary polymorphism of rashes. Hand eczema develops against the background of altered reactivity and genetic predisposition under the adverse effects of endogenous and exogenous factors. Hand eczema has a chronic course and is characterized by a wide range of clinical manifestations. The prevalence of eczematous lesions of the hands among the adult population is 1–2%, and among all skin diseases – 30–40%. The disease has an extremely negative impact on the quality of life, ability to work, career prospects and the social status of a person. The long course of eczematous lesions of the hands can be complicated by a secondary infection: bacterial and mycotic flora. Therefore, choosing the right and effective treatment for hand eczema is a particularly difficult task for a dermatologist. In recent years, a multicomponent drug based on gentamicin sulfate, dexpanthenol, mometasone furoate and econazole nitrate has been widely used for the treatment of hand eczema due to its high efficacy, tolerability, and safety. The use of this multicomponent drug in monotherapy for hand eczema is effective, leads to clinical remission and restoration of the quality of life of patients and is not accompanied by side effects and complications. This review focuses on the epidemiology, clinical features, and treatment options for hand eczema. Clinical experience with the use of a multicomponent drug in patients with hand eczema complicated by infection is also given

Zen law and features of liquidus-solidus curves in binary state diagrams based on elements VIIIA and IB of the periodic table

The paper presents the analysis of binary state diagrams based on elements VIIIA and IB of the periodic table and crystal geometry parameters of solid solutions and intermetallic compositions. The analysis shows an explicit correlation between the type of the evolution of phase diagrams classified by Lebedev depending on the nature of atomic volume deviations observed in solid solutions and intermetallic compounds from Zen law

Electron-ion-plasma modification of the structure and properties of commercial steels

The work is devoted to the structural-phase analysis of steels of the austenitic and martensitic grade, irradiated with a high-intensity pulsed electron beam of the submillisecond duration of exposure in the mode of the surface layer melting. A thermodynamic analysis of phase transformations occurring during heat treatment in alloys of the composition Fe-Cr-C and Fe-Cr-Ni-C, which are the basis of steels 20X13 and 12X18H10T, is carried out. It is shown that formation of solid solutions on the basis of [alpha]-iron (BCC crystalline lattice) and [gamma]- iron (FCC crystalline lattice) as well as the entire range of carbide phases of a complex elemental composition (M[23]C[6], M[7]C[3] и M[3]C, where symbol M refers to atoms of metallic elements Fe, Cr, and Ni) is possible in equilibrium conditions in given materials. The irradiation of steels 12X18H10T and 20X13 with a high-intensity pulsed electron beam of the submillisecond duration of exposure is carried out. It is shown that the electron-beam processing of steel in the melting mode and the subsequent rapid crystallization is accompanied by a significant transformation of the surface layer structure, consisting in complete dissolution of original carbide phase particles; in formation of dendritic crystallization cells of submicron sizes; in occurrence of martensitic [gamma]->[alpha] and [gamma]->[epsilon] transformation; in re-allocation of nanosized particles of carbide and intermetallic phases

Современное состояние методов коррекции инволюционных изменений кожи и место фотодинамической терапии среди них

This work is a review of modern scientific data on the process of aging, as well as the prospect of using photodynamic therapy for correction of involutional skin changes in the age cohorts, cohorts with a burdened medical history, including cancerous and precancerous skin neoplasms. The data on the predicted increase in life expectancy and, as a consequence, the potential risk of pathologies, including those with skin localization, progression of malignancy processes, as well as the formation of de novo elements, is presented. The increase in life expectancy also demonstrates the socialization of the elderly population, along with the increasing need for correction of involutional skin changes. However, considering the risks associated with the chronic diseases and increased malignancy in this cohort, methods have to be carefully selected. One such technique is photodynamic therapy (PDT). PDT is actively used in oncology, and recently has been increasingly showing its aesthetic effectiveness. It can be predictably used not only on cancer patients, but also in an age cohort.Данная работа представляет собой обзор современных научных данных о процессах старения кожи, а также о перспективе использования метода фотодинамической терапии для коррекции инволюционных изменений кожи у возрастного населения. Приводятся данные прогнозируемого увеличения продолжительности жизни и, как следствие, потенциального риска возникновения патологий, в том числе кожной локализации. Увеличение продолжительности жизни также демонстрирует и социализацию пожилого населения, вместе с тем возрастающую потребность в преображении и коррекции инволюционных изменений кожи, но, учитывая риски в связи с наличием хронических заболеваний и возрастающей малигнизации данной когорты, следует тщательно подбирать методики, учитывая вышеперечисленные особенности. Одним из таких методов является фотодинамическая терапия. Фотодинамическая терапия активно применяется в онкологии, а в последнее время все чаще показывает свою эффективность в эстетическом направлении, соответственно прогнозируемо может использоваться не только у онкологических больных, но и возрастной когорты

Синтез коллагена в коже: генетические и эпигенетические аспекты

One of the most important functions of the skin, mechanical, is provided by collagen fibers and their interaction with other elements of the extracellular matrix. Synthesis of collagen fibers is a complex multistep process. At each stage, disturbances may occur, leading, as a result, to a decrease in the mechanical properties of the connective tissue. In clinical practice, disorders of collagen synthesis are manifested through increased skin laxity and looseness and premature aging. In addition to the clinical presentation, it is important for the cosmetologist and dermatologist to understand the etiology and pathogenesis of collagenopathies. The present review summarizes and systematizes available information about the role of genetic and epigenetic factors in the synthesis of collagen fibers in the skin. Understanding the etiology of collagen synthesis disorders can allow doctors to prescribe pathogenetically grounded treatment with the most effective results and minimize adverse reactions.Одна из важных функций кожи, механическая, обеспечивается коллагеновыми волокнами и их взаимодействием с другими элементами внеклеточного матрикса. Синтез коллагеновых волокон – это сложный многоэтапный процесс. На каждом этапе может возникнуть нарушение, приводящее в итоге к снижению механических свойств соединительной ткани. Клинически нарушения коллагенообразования проявляются в виде повышенной дряблости, рыхлости кожи, раннего проявления признаков старения лица. Кроме клинической картины, врачу косметологу и дерматологу важно понимать этиологию и патогенез коллагенопатий. В нашем обзоре мы обобщили и систематизировали имеющуюся информацию о роли генетических и эпигенетических факторов в процессе синтеза коллагеновых волокон кожи. Понимание патогенеза нарушения коллагенообразования может позволить врачам назначать патогенетически обоснованное лечение с достижением наиболее эффективных результатов и минимизацией нежелательных реакций