Journal "Research Bulletin of National Technical University of Ukraine "Kyiv Polytechnic Institute" (Naukovi visti) publishes original research results and practical developments from areas of technical, physical, mathematical, chemical and biological sciences.

Fine-Dispersed Iron (III) Oxyhydroxides Synthesis: Carbamide Precipitation

The conditions of carbamide precipitation synthesis of fine-dispersed iron (III) oxyhidroxides from iron (III) sulphate and nitrate solutions were found out. In order to determine the necessary precipitant amount potentiometric precipitation titration of iron (III) sulphate and nitrate solutions with ammonia and hydrolyzed carbamide solutions were carried out. The results of these researches are expounded.

Influence of Preconditioning on the Absorbency and Strengh of Ammonium Nitrate Granules Grade B

The retention capacity of granulated ammonium nitrate grade B with respect to the liquid fuel due to pretreatment of the granules has been increased, and energy-condensed systems for mining have been developed. Processing technology including opening of hard shell of granules without formation of through pores and creating a rigid framework of slightly soluble compounds in the pores. It has been found, that treatment with a solution of iron (III) chloride and further heating provides formation of iron (III) hydroxyl compounds framework with the developed surface in the pores of granules.

Temperature Measurement Uncertainty of Patient by Medical Thermal Imager

The purpose of this article is to develop the method of estimation and research of measurement temperature uncertainty by the medical thermal imager in pathological zones depending on the distance between the patient and the thermal imager. The proposed method is based on the noise equivalent temperature difference (NETD) which depends on the linear objective magnification of the thermal imager.

Physical and Chemical Conditions of Complex Saturation Carbon Steel 45 by Silicon and Chrome in Medium of Chlorine

The package of the applied programs with base of the thermodynamic data was used and the theoretical analysis of physical and chemical conditions of complex saturation carbon steel by silicon and chrome in medium of chlorine in the closed reactionary space was carried out at the lowered pressure of a gas phase. The influence of structure of initial components of a sating mix on equilibrium structure gas and condensed of phases of process chromosilicided is revealed.

Mathematical Modelling of Dynamics of the Vibroprotective System Equipped with Roller Absorber

Using the methods of mathematical modeling to develop numeral-analytical approach for determination of equations of ACHKH of the nonlinear vibroprotective system with a new isochronous roller absorber in the first approaching and to define the optimum parameters of its tuning. For the conclusion of equations ACHKH the averaging method of W. Ritz, adapted to the probed task, was used. For the solution of nonlinear algebraic equations of ACHKH of the system the special programmatic complex was developed in a non-obvious form.

Researches of Surface Quality Parameters of High Speed Sliding Bearings from Composite Materials for Printing Machines at DIamond Grinding

In the article the research results of defect layers formation on surface of high-speed sliding bearings made of new high-alloy composite materials from tool steels wastes and intended for printing machines have been presented. Such quality parameters of surface like cold-work strengthening and distortions of the 2-nd type are supplied by the result of interaction between force and temperature fields appearing on the top of diamond grain at fine diamond grinding of friction surfaces of sliding bearings were shown.

The Study of the Structure of Laminar Currents in Recirculating Channels with Developed Surface

In order to research influence of parameters of the developed surface on structure of a laminar current of viscous incompressible liquid in ring channels the computing model, and algorithm of creation of profiles of speed has been offered. This case deals with a homogeneous layer of obstacles – cylindrical protrusions, distance between which ensures the absence of hydrodynamics interactions. Numerical calculations allowed analyzing dependence of the maximum and average speeds of a stream from density of ledges on a surface of the channel and from their height.

Composite Design Pattern Application and Application of the LINQ Technology in the Context of the Prefix Encoding of Text Using the Huffman Algorithm

The designed methods are the implementation of the object-oriented architecture as the class diagram corresponding to the implementation of the Composite design pattern according to the requirements of the flexible implementation of the Huffman tree, the method of the dynamic iterative Huffman tree building. This tree uses the dynamic collection of the node interface using the Visual C# language and the creation method of the initial set of the leaf nodes using the LINQ technology.

Application of Discrete Structures and Numerical Sequences in Block Codes

The purpose to compress information using composition of universal codes with the recursive algorithm of original data recovery was achieved in this work. It obtains compression coefficient higher than in symbolic coding. Proposed method of time coding has reasonable values of compression coefficient and its purpose is coding with compression. For this purpose, entirely new kind of universal coding with the polybasic numeral system was created.

The Information Technology of Automated Data Processing in the Multi-Channel Ultrasonic Measurement Systems

The article is devoted to the application of information technology for the ultrasonic measurement of linear distances. The most attention is done on improving the accuracy and expansion bands of measurement. For that problem’s solving, using of the multi-channel ultrasonic measuring system that consists a plurality of sensors with various measuring characteristics is proposed.