Effect of preliminary vacuum plasma treatment on coating adhesion

The paper presents research results on the adhesion properties of Si coatings synthesized by different methods and under different conditions of preliminary vacuum ion plasma treatment of substrates with subsequent magnetron sputtering. The substrate surface was pretreated with low-energy ion beams, high-energy ion beams, gas discharge plasma, and plasma produced by a magnetron sputtering system. The vacuum conditions (pump type, pressure, etc.), the ion current density, and the bias parameters (pulse repetition frequency and duration) were varied. The research results demonstrate a considerable effect of plasma immersion ion implantation on the adhesion of Si coatings to NiTi substrates

Effect of bias voltage on coating homogeneity in plasma immersion ion implantation

The paper presents research results demonstrating the influence of bias on the homogeneity of plasma immersion ion implantation. The research results allow the conclusion that plasma immersion ion implantation can be used to advantage for surface modification of medical materials, e.g., nickel-titanium (NiTi) alloys. In particular, doing of NiTi with silicon at pulsed bias provides highly homogeneous surface treatment

Plasma immersion ion implantation for the efficient surface modification of medical materials

The paper reports on a new method of plasma immersion ion implantation for the surface modification of medical materials using the example of nickel-titanium (NiTi) alloys much used for manufacturing medical implants. The chemical composition and surface properties of NiTi alloys doped with silicon by conventional ion implantation and by the proposed plasma immersion method are compared. It is shown that the new plasma immersion method is more efficient than conventional ion beam treatment and provides Si implantation into NiTi surface layers through a depth of a hundred nanometers at low bias voltages (400 V) and temperatures (≤150°C) of the substrate. The research results suggest that the chemical composition and surface properties of materials required for medicine, e.g., NiTi alloys, can be successfully attained through modification by the proposed method of plasma immersion ion implantation and by other methods based on the proposed vacuum equipment without using any conventional ion beam treatment

Plasma immersion ion implantation for surface treatment of complex branched structures

The paper presents experimental results demonstrating the capabilities of plasma immersion ion implantation of silicon (Si) for surface treatment of complex branched structures such are self-expanding intravascular nickel-titanium (NiTi) stents. Using NiTi stents of diameter 4 and 8 mm, it is shown that plasma immersion ion implantation can provide rather homogeneous doping of their outer and inner surfaces with Si atoms. Also presented are research data on the processes that determine the thickness, composition, and structure of surface layers subjected to this type of treatment

Integrable quadratic Hamiltonians on so(4) and so(3,1)

We investigate a special class of quadratic Hamiltonians on so(4) and so(3,1) and describe Hamiltonians that have additional polynomial integrals. One of the main results is a new integrable case with an integral of sixth degree.Comment: 16 page

Analysis of macroeconomic development indicators of the region

Abstract Regional aspect of forecasting in conditions of Russian economic environment plays particular role, since without the consideration of specific character of regions development no long-term national programs can be realized, as well as implementation of any social or economic reforms becomes impossible. The interrelation between economic advancement and social factors in the Republic of Mari El reviewed in this this article creates awareness of specific interrelation of gross regional product with considered factors and their influence on this index value

Creation of a magnetic driven gate for THz rays

In this paper, magnetic fluids based on iron oxide Fe3O4 and 5BDSR alloy were obtained. Magnetic particles were obtained by nanosecond pulsed laser ablation. The preparation of the magnetic fluid was carried out by mechanical and ultrasonic stirring in a solution of polymethylphenylsiloxane. It is shown that under the influence of an external magnetic field, the spectral properties of the magnetic fluid of the 5BDSR alloy correspond to characteristics that can be used to create a magnetic gate

A Dynamic Model of Regional Economic Growth

The article is devoted to the construction of a dynamic model of economic growth Solow and Solow model taking into account the delay in the commissioning of assets for the Volga Federal District. We study and analyze the theoretical methods of investigation method of constructing such models and the urgency of the topic of research. To build the model were selected macroeconomic indicators such as gross regional product, the value of fixed assets, the labor force employed in the economy, the economically active population, the value of investments in fixed assets, consumption. On the basis of the constructed models were constructed projections of key macroeconomic parameters included in the model for 2013-2015. In order to assess the accuracy of the predicted values obtained by the Solow model, built four equations of various growth curves. It should be noted that these trend lines very well describe the gross regional product of the Volga Federal District. The best model is the polynomial trend line; the coefficient of determination is the maximum. Predicted values are similar between the Solow model and polynomial trend line. It is shown that elasticity of labor much more elasticity in terms of capital to the Volga Federal District, as a result, it is possible to make an unequivocal conclusion about the extensive nature of economic growth. DOI: 10.5901/mjss.2015.v6n3s7p13