136 research outputs found
Lost pattern complex composition effect on steel casting structure and properties
One of the ways to produce high-quality castings at relatively inexpensive costs is lost foam casting. However, the existing problem of surface carburization due to the burnout of the polystyrene pattern and general contamination of the near-surface layer is one of the factors that hinder the widespread use of this casting method. In order to minimize carburization, it is proposed to use a complex pattern composition. The results of studying the effect of the pattern complex composition and the technological parameters of manufacturing the “Through Cover” casting for the ingot purity and structure are presented
Shell forming mode effect on casting quality
The paper deals with the influence of shell forming modes on some parameters of castings: the surface and internal defects. The degree of roughness and stress concentration were determined on the castings obtained under production conditions. According to the result, it was found that the use of variable pressure in the formation of the shell ensures the purity of the casting and the reduction of the stress level in the casting
The corrosion resistant coating with halloysite nanoparticles
The process of application of coating on metal surfaces is described in this article. The composition with 100 % corrosion preventing substance + 42,5 % acetone + 10 % halloysite was recognized as the most appropriate for coating, and it provides the best corrosion resistance of hydraulic pump details. The impellers of circulation pumps for water delivery in heating system fail after 5 - 6 months because of the galling of work flutes, as water doesn’t pass through the chemical purification. After applying corrosion resistant coating with halloysite the lifetime of impellers increases. The essence of which is dipping the impeller into hydrochloric acid with 24 hour keeping in it, then it is dried in dryer up to 4 hours. The lifetime of this impeller increases 1,8 fold and it was approximately 9 months
Оценка устойчивости территории вблизи карстовых провалов в населенном пункте Березники (Нижегородская область)
The article provides with the results of a comprehensive assessment of the stability of the area near the karst sinkholes at Berezniki, Gaginsky district. The materials of geophysical surveys obtained by the method of vertical electric sounding were interpreted taking into account the karstological drilling data. Weakened zones are outlined along the apparent resistivity sections. Dependence of sounding results on the distance from the nearest sinkhole was analyzed. The intensity of sinkhole formation and the average diameter of the karst sinkhole were calculated.В статье приведена комплексная оценка устойчивости территории вблизи карстовых провалов с. Березники Гагинского района. Проинтерпретированы материалы полевых геофизических исследований, полученные методом вертикального электрического зондирования, с учетом данных карстологического бурения. Оконтурены ослабленные участки по глубинным срезам кажущихся сопротивлений. Выполнено зондирование территории по удаленности от ближайшего карстопроявления. Посчитаны интенсивность провалообразования и средний диаметр карстового провала
Multilevel System of Studying Plague Microbe Strains Proprties in the Republic of Kazakhstan
The study of freshly isolated cultures is necessary to form an objective idea of the properties of plague microbe natural populations. The analysis of the levels of investigating the properties of strains has been carried out and the characteristics of Yersinia pestis in Kazakhstan are presented. The results of studying the phenotypic and genetic properties of plague microbe natural strains are provided. Following the epizootiological survey of natural plague foci, the museums of live cultures at plague control stations annually receive strains of plague pathogen, which are transferred to the National Collection of Microorganisms of the National Scientific Center of Particularly Dangerous Infections (NSCPDI). One of the main points of Y. pestis strains analysis is the determination of their typicality/atypicality. The study of strains begins at the moment of their isolation by anti-epidemic units. The primary identification of strains is carried out in laboratories of anti-epidemic units by morphology, sensitivity to plague and pseudotuberculosis bacteriophages, fermentation of glycerol, rhamnose and sucrose. In the laboratories of plague control stations and departments, fermentation of maltose and arabinose, denitrification, amino acid requirements, virulence, sensitivity to antibiotics are additionally investigated. Analysis of strains virulence includes determination of calcium dependence, the presence and amount of F1, pesticinogenicity and sensitivity to pesticin 1 and virulence for white mice. The assessment and preservation of the collected gene pool in the NSCPDI National Collection includes various activities, one of the main ones is an in-depth study of all features using standard microbiological methods, molecular methods for complete identification and creation of a data bank containing information about the genome of strains at different intensity of the epizootic process. The NSCPDI has a digital database on the registration and movement of strains, equipment for molecular research. The collection evaluates properties, systematizes information, and ensures the viability of plague pathogen strains for longterm storage
International Cooperation of Kazakhstan in the Prevention of Particularly Dangerous Infections
The dependence of the incidence of various nosologies on the epidemic situation in neighboring countries has been a feature of the epidemic process in recent years. In this regard, it is of particular importance to carry out joint anti-epidemic and preventive measures in border areas in order to prevent the importation of dangerous infections into the territory of neighboring states. The aim of the work was to analyze the results of international cooperation in the prevention of particularly dangerous infections. Presented are the areas of cooperation and outcomes of joint research activities. Measures for cooperation between the relevant institutions of the Ministry of Health of the Republic of Kazakhstan and the Rospotrebnadzor on the operational exchange of information in case of emergencies, joint research work on the monitoring of particularly dangerous and other natural-focal infectious diseases in the border areas, joint seminars, scientific and practical conferences on the introduction of modern methods of laboratory diagnostics into practice, internships on the exchange of experience in epizootiological survey in foci of particularly dangerous infections are described in the paper. Examples of Russian-Kazakh cooperation are provided. The results of a joint epizootiological survey of the territory of the Kazakh part of the Altai Mountains are presented. On a global scale, cases of plague and other particularly dangerous infections in any geographic region can constitute international public health emergencies and this type of threat requires international cooperation
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