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Eurasian Chemico-Technological Journal
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This is an Open Access Journal

Open Access journal
ISSN (Print) 1562-3920 - ISSN (Online) 2522-4867
Published by Al-Farabi Kazakh National University

[2 journals]

Effect of Lattice Structure and Composite Precursor on Mechanical
Properties of 3D-Printed Bone Scaffolds
- Authors: M. Shams, Z. Mansurov, C. Daulbayev, B. Bakbolat
  Pages: 257‒ - 257‒
  Abstract: This article presents an investigation on designing and fabricating scaffolds with different structures, desired porosity, composition, and surface area to volume ratio (SA:V) for orthopedic applications by using the computer-aided design (CAD) and the stereolithography (SLA) 3D printing technique. Different triply periodic minimal surfaces (TPMS) and functionally graded lattice structures (FGLS) were designed based on various cell geometries. Finite element analysis (FEA), tensile and compression tests were carried out, and the results are presented. Two different resin compositions were used to print the models and compare the effect of resin precursors on the mechanical properties of scaffolds. The first was a biodegradable resin made from soybean oil commercially available on the market (made by Anycubic Co.). The second was a mixture of biodegradable UV-cured resin with 5% W/W of hydroxyapatite (HA) and 5% W/W calcium pyrophosphate (CPP). Bio-Hydroxyapatite and Bio-Calcium Pyrophosphate were obtained from eggshells waste and characterized using XRD and FESEM. The obtained data show that adding resin precursors (HA/CPP) slightly decreases the mechanical strength of printed scaffolds; however, considering their extraordinary effect on bone regeneration, this small effect can be ignored, and HA/CPP can be used as an ideal agent in bioscaffolds.
  PubDate: 2022-01-31
  DOI: 10.18321/ectj1129
  Issue No: Vol. 23, No. 4 (2022)
Genesis and Properties of MOx/CNTs (M = Ce, Cu, Mo) Catalysts for Aerobic
Oxidative Desulfurization of a Model Diesel Fuel
- Authors: Е.V. Matus, S.A. Yashnik, A.V. Salnikov, L.M. Khitsova, A.N. Popova, A.P. Nikitin, S.A. Sozinov, Z.R. Ismagilov
  Pages: 267‒ - 267‒
  Abstract: Aerobic oxidative desulfurization of a model diesel fuel over MOx/CNTs catalysts (M = Ce, Cu, Mo) was studied to develop innovative technology for cleaning motor fuels to EURO-5 standard. It was shown that the thermal stability of catalysts improves in the following order of metal Сu < Сe < Мо. The disordering of the carbon matrix of support increases in the next row of M: Mo < Ce < Cu, which is accompanied by an increase in the specific surface area of the samples (40 → 105 m2/g). The forms of stabilization of the active component (CeO2, CuO/Cu2O/ Cu, or MoO3/MoO2) were revealed, indicating a partial reduction of the metal cations during the thermal decomposition of copper and molybdenum precursor compounds deposited on CNTs. In oxidative desulfurization of a model diesel fuel over MOx/CNTs catalysts at 150 °C the total conversion of dibenzothiophene increased in the next row of M: Се < Сu < Мо. It was found that at 150 °C over the optimum MoOx/CNTs catalyst the highest dibenzothiophene conversion 95–99% is observed. It was assumed that the high activity of MoOx/CNTs is associated with both the oxidizing ability and the tendency of MoOx to chemosorption of sulfur compounds.
  PubDate: 2022-01-31
  DOI: 10.18321/ectj1130
  Issue No: Vol. 23, No. 4 (2022)
The Role of Chain Processes in Cool Flames and Soot Formation
- Authors: Z.A. Mansurov
  Pages: 235 - 245
  Abstract: The 125th anniversary of Academician N.N. Semenov, the great natural scientist of the 20th century, is a significant event for the world scientific community. With his discoveries and tireless scientific, organizational, pedagogical, and social activities, he made an invaluable contribution to the formation of chemical physics and to the development of physics, chemistry, and biology. Nobel Prize laureate, academician N.N. Semenov played a huge role in the creation of the Department of Chemical Kinetics and Combustion of the Al-Farabi Kazakh National University and the Institute for Problems in Combustion. Contacts with the disciples of Academician N.N. Semenov made it possible for the researchers of the Institute for Problems in Combustion to discuss their candidate and doctoral dissertations at the seminars of the Institute of Chemical Physics in Moscow. With the support of N.N. Semenov, Ya.B. Zel’dovich, and A.G. Merzhanov, All-Union Symposia on Combustion and Explosion (1980 in Alma-Ata) and on Structural Macrokinetics (1984 in Alma-Ata) were organized. The article provides an overview of the author’s works on studying the structure of the front of cool flames of diethyl ether and butane, the preflame zone of normal propane flames, and soot formation during combustion of hydrocarbons. The phenomenology, kinetics and mechanism of soot formation, and the influence of various factors on the formation of polycyclic aromatic hydrocarbons, carbon nanotubes, fullerenes, graphene, and soot are considered.
  PubDate: 2021-12-31
  DOI: 10.18321/ectj1127
  Issue No: Vol. 23, No. 4 (2021)
Study on the Rapid Preparation of Zinc Oxide Nanotubes by Galvanostatic
Etching
- Authors: Jingsong Sun, Jinxing Cao, Xiaohong Jiang
  Pages: 247‒ - 247‒
  Abstract: At present, most of the methods for preparing ZnO nanotubes are chemical etching of ZnO nanorods, which is inefficient and takes a long time. In this paper, ZnO nanotubes were successfully prepared by galvanostatic etching. Nanotubes prepared by galvanostatic etching only took 1/6 of the time of chemical etching. The ZnO nanotubes obtained by two different methods were tested by XRD and SEM. It is found that the crystal structure and crystallinity of the ZnO nanotubes obtained by galvanostatic etching are unchanged, and the internal corrosion of the nanotubes by galvanostatic etching is more thorough and has a larger specific surface area. In the tests of UV-vis spectrophotometry, fluorescence spectra and electrochemical performance test, the optical properties and electrochemical performance of ZnO nanotubes obtained by galvanostatic etching are better than those obtained by chemical etching. Because the ZnO nanotubes obtained by galvanostatic etching have larger specific surface area, better optical properties and better electrochemical performance, they have a greater application prospect in sensors and ultraviolet light detectors.
  PubDate: 2021-12-31
  DOI: 10.18321/ectj1128
  Issue No: Vol. 23, No. 4 (2021)
Purification of Tomato Bushy Stunt Virus Particles by One-Step
Hydroxyapatite Column Chromatography
- Authors: Zh. Tleukulova, Z. Stamgaliyeva, A. Dildabek, G. Mukiyanova, R.T. Omarov
  Pages: 277‒ - 277‒
  Abstract: The main aim of this work was to develop a time-saving and cost-effective purification method of infectious plant viral nanoparticles. Virions of Tomato bushy stunt virus (TBSV), which is a member of Tombusvirus genus, were purified by one-step Bio-gel HT Hydroxyapatite (HA) column chromatography. Extracts from Nicotiana benthamiana plants infected with TBSV were directly loaded onto the HA column and eluted by 10 mM sodium phosphate buffer (pH 6.8). A specificity of virions has been confirmed by immunoblotting and electron microscopy. Homogeneity of virions was tested by SDS-PAGE, where only 41 kDa polypeptide bands referring to the capsid protein of TBSV were detected by Coomassie staining. The biological infectious activity of a purified material was demonstrated by observing TBSV-specific symptoms observed in N. benthamiana plants at 7‒10 days of post-inoculation (dpi). Moreover, purified virions were used for immunization of the BALb/c mouse to raise primary antibodies against the TBSV virus. Our results show that in low concentrations of sodium phosphate buffer total proteins extracted from infected plants adsorb to HA sorbent, while viral particles do not adsorb to the HA matrix and flow throw column due to Ca2+ ions implicated in TBSV virions’ structure. This highly effective and simple virus purification protocol can also be used for the isolation of other plant virions.
  PubDate: 2021-12-31
  DOI: 10.18321/ectj1131
  Issue No: Vol. 23, No. 4 (2021)
The Current Radiation Situation of the Territory Near the Uranium Mining
Enterprises of Northern Kazakhstan
- Authors: A.S. Nygymanova, A.G. Pirmanova, M.M. Bakhtin, K.A. Kuterbekov, P.K. Kazymbet, A.M. Kabyshev, B.U. Baikhozhayeva
  Pages: 283‒ - 283‒
  Abstract: Radioactive waste near the industrial zones of the mining administrations of the Stepnogorsk Mining and Chemical Combine, which occupy vast areas of the territory, remains an urgent problem for Northern Kazakhstan. For example, waste rock processing referred to as “tailings”, is contained in huge industrial basin-lakes, called tailings. Each liter of jelly-like “pulp”, in addition to carbonates of arsenic, molybdenum, phosphorus and other chemical elements, contains up to 1 g of active uranium, as well as radium and thorium. As a result of the pedestrian gamma survey, the authors identified a locally contaminated area in the northwest direction from the sanitary protection zone of the tailing dump of the Stepnogorsk Mining and Chemical Combine. It has been established that, according to the indices of radioactive contamination of water bodies, the stagnant water bodies of the Manybaiskiy and Sulukamysskiy thalweg located behind the sanitary protection zone of the tailing dump of the Stepnogorsk Mining and Chemical Combine are classified as contaminated.
  PubDate: 2021-12-31
  DOI: 10.18321/ectj1132
  Issue No: Vol. 23, No. 4 (2021)