Journal of Chemical Technology and Metallurgy最新文献

{"title":"APPLICATION OF ILLUSTRATIVE MATERIALS IN FOREIGN LANGUAGE TEACHING FOR ENGINEERING SPECIALTIES","authors":"Tsvetelina Vukadinova","doi":"10.59957/jctm.v59.i2.2024.30","DOIUrl":"https://doi.org/10.59957/jctm.v59.i2.2024.30","url":null,"abstract":"In the process of learning a foreign language for specific purposes, the most suitable, adequate, and innovative approaches are constantly being sought, concerning how and which/what additional (supplementary) materials contribute to more effective 1) subject and 2) language content learning, as well as concerning easy knowledge transfer - from the native to the foreign language. The following paper examines the importance of various content components and illustrative materials as supporting engineering students’ foreign language teaching and learning. By means of an exploratory survey (survey card), the opinion of the students was collected and analyzed, which is indicative of the materials suitable for application in a working environment in their relation with the conceptual apparatus in the studied material in the native and foreign languages.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"233 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140514761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CHEMICAL REMOVAL OF IRON SULFIDE DEPOSIT IN PIPES FROM OIL AND SOUR GAS PRODUCTION","authors":"F. Mainier, André Armando Mendonça de Alencar Junior, E. F. Barros","doi":"10.59957/jctm.v59.i1.2024.19","DOIUrl":"https://doi.org/10.59957/jctm.v59.i1.2024.19","url":null,"abstract":"Hydrogen sulfide (H2S) and carbon dioxide (CO2) present in oil and natural gas cause mild steel corrosion, potentially resulting in formation of corrosion product layers on the internal surfaces of tubulars. In field experiences relating to the research reported herein, this has led to restrictions on the flow of water produced from a three-phase horizontal separator. This paper demonstrates a specific case of chemical removal of relatively hard, dark, and adherent heterogeneous deposits on the internal surface of the pipe. The phases involved in this process are iron sulfide, iron oxides and calcium carbonate existing as scales/corrosion products. To evaluate their dissolution, laboratory tests were conducted using hydrochloric acid (HCl) with additions of chlorine in the form of calcium hypochlorite [Ca(ClO)2]. Appropriate safety measures were taken employed, considering hazards associated with chlorine and toxicity of hydrogen sulfide. The treatment regime had 87 % effectiveness for scale removal in combination with propargyl alcohol (2-propyn-1-ol) as a corrosion inhibitor.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"4 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139450937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D SPACE KINEMATICS OF A ROBOT FOR PROCESS AUTOMATION IN METALLURGY","authors":"Valentin Slavov, Verjinia Aleksandrova","doi":"10.59957/jctm.v59.i2.2024.25","DOIUrl":"https://doi.org/10.59957/jctm.v59.i2.2024.25","url":null,"abstract":"This paper presents the main results of a study on the kinematics in 3D space of a robot used for process automation in metallurgy. \u0000The robot is studied as a mechanical system with twelve degrees of freedom consisting of seven rigid bodies. The transition matrices between the local and reference coordinate systems are defined in symbolic form. The position vectors and linear velocities of characteristic points are also defined in symbolic form as well as angular velocities of bodies from the mechanical system. A calculation algorithm is compiled and entered into a standard mathematical software product. Results are obtained in symbolic form and are valid for all mechanical systems with an analogous dynamic model. The kinematics results represent a basis for studying the dynamics and vibrations of a robot for automating processes in metallurgy.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140514443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GLASS-FORMATION IN THE As2Se3-GeSe2-ZnTe SYSTEM","authors":"L. Aljihmani, Tihomir Petrov","doi":"10.59957/jctm.v59.i2.2024.8","DOIUrl":"https://doi.org/10.59957/jctm.v59.i2.2024.8","url":null,"abstract":"New chalcogenide samples from the As2Se3-GeSe2-ZnTe system are synthesized by melt quenching technique in evacuated to a residual pressure of 1.10-3 Pa quartz ampoules. The specimens from the investigated system are prepared by direct mono-temperature synthesis with conditions conformed to the physico-chemical features of the initial compounds. The state of the bulk samples (glassy, crystalline, glassy + crystalline) is proven by visual, X-ray diffraction, and microscopic analyses. The glass-forming region within the system is outlined using the results of the performed syntheses and analyses. It lies on the As2Se 3-GeSe2 side and partially on the As2Se3-ZnTe (from 0 to 5 mol % ZnTe) and GeSe2 -ZnTe (from 0 to 15 mol % ZnTe) sides. The maximum solubility of ZnTe in the glasses is 20 mol %. A presence of a crystallizing phase As2ZnGe is registered in the XRD-investigated samples.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"182 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140514778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EVALUATION OF THE OXIDATIVE THERMAL STABILITY OF FISH OIL WITH THE ADDITION OF PUMPKIN SEED OIL OR ROSEMARY EXTRACT","authors":"Artan Gashi, Georgi Chernev, E. Symoniuk, Zivko Jankulovski, Carolina Krebs de Souza, Fatos Rexhepi","doi":"10.59957/jctm.v59.i1.2024.7","DOIUrl":"https://doi.org/10.59957/jctm.v59.i1.2024.7","url":null,"abstract":"The present study investigates the thermal stability of the commercial fish oil, rich in unsaturated fatty acids, and compares the sensory properties of pure fish oil with a mixture of fish oil and added rosemary extract (RE), as well as roasted and unroasted pumpkin seed oil, at a concentration of 5 %. All samples were monitored using FTIR spectroscopy to measure the specific absorptivity of conjugated dienes (CDs) and conjugated trienes (CTs), as well as the peroxide value. Additionally, GC/FID was employed to evaluate the oxidative degree of the fish oil and compare the antioxidative effect of roasted pumpkin seed oil, specifically in comparison to rosemary extract. For this purpose, the oil stability was optimized by comparing the oxidation levels of fish oils exposed to range of temperature, including 23°C, 50°C, 70°C, 90°C, and 110°C. This was done in the presence of a low percent of rosemary extract, unroasted pumpkin seed oil (UPSO), and roasted pumpkin seed oil (RPSO). Based on the obtained results, a clear difference is observed in the blended samples, particularly when roasted pumpkin seed oil is used. This difference is evident in the ultraviolet chemical parameters, fatty acid profile, and most notably in the optimized FTIR vibrational bands. The ratios of area peaks such as 3444/2854, 1745/2854 and 3010/2854 are considered important parameters for monitoring the chemical changes and lipid stability. All the chemical parameters confirm the possibility of enhancing the stability of fish oil by blending it with healthy pumpkin seedoil. The composition of pumpkin seed oil increases the stability of fish oil. Consequently, it is evident that pumpkin seed oil, known for its high healthy benefits, can successfully be used to improve the thermal and oxidative stability of fish oil lipids. The principal component analysis (PCA) was used to define clusters, which revealed a wide range of both chemically changed and unchanged samples. The application of FTIR spectroscopy as an alternative method provides excellent parameters for easy operation, affordability, and ecological considerations, making in an efficient tool for controlling the quality of edible oils.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"60 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EFFECTS OF ZEOLITE INCORPORATION AND INERT FILLERS ON THE CURING OF CEMENT MORTARS","authors":"Vilma Petkova, V. Stoyanov, B. Kostova, Katerina Mihaylova","doi":"10.59957/jctm.v59.i2.2024.9","DOIUrl":"https://doi.org/10.59957/jctm.v59.i2.2024.9","url":null,"abstract":"One of the main approaches to reducing the environmental impacts of the construction industry is the use of mineral additives reducing the use of cement in mortars and concretes for construction. The objects of this research are different cement composites with high content of inert mineral fillers (marble and quartz sand), the influence of zeolite incorporation on the microstructure, and low water-cement ratio, obtained after the hydration of white portland cement.In this study, the evolution of the curing processes and the crystal formation during up to 120 days of water-curing are investigated. Moreover, the effects of replacing up to 10 wt. % of white cement with natural zeolite are studied. Attention was focused on the general microstructural development during curing with special attention on the evolution and morphology of pore space and the observed  calcium silicate hydrates (C–S–H), portlandite, and carbonate-containing phases.The phase composition (newly formed phases as well as the formation of C-S-H gel) is defined by using powder X-Ray diffraction and SEM. The experimental data shows that the cement composites with the inert marble filler as an additive lead to the creation of carbo-aluminates. The incorporation of up to 10 percent of clinoptilolite in concrete mixtures by mass of the total cementitious components is more efficient when used in lower strength mixes. A significant reduction in the workability of the fresh mortars is not observed, but the high surface area of zeolite reduces bleeding and accelerates setting without any strong effects on the other physical and technological properties of fresh mortars.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"284 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140514483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INVESTIGATION OF THE MICROSTRUCTURE OF AISI 321 STAINLESS STEEL AFTER LASER SURFACE MELTING","authors":"Tsanka D. Dikova, Natalina K. Panova, I. Parushev","doi":"10.59957/jctm.v59.i1.2024.24","DOIUrl":"https://doi.org/10.59957/jctm.v59.i1.2024.24","url":null,"abstract":"The aim of the present paper is to investigate the microstructure of laser-melted surface layers of austenitic steel for biomedical applications. The surface of prismatic specimens from AISI 321 stainless steel was treated by continuous CO2 laser. Three modes of laser processing were used, ensuring surface melting. The microstructure was observed by OM and SEM, while the chemical composition was investigated by EDX analysis. It was found that the microstructure of as-delivered steel was two-phase and relatively inhomogeneous in morphology and chemical composition. It consisted of austenite with grain sizes between 20 - 150 μm, relatively large amount of striped δ-ferrite and spherical carbides along the grain boundaries. After laser melting, the microstructure remained two-phase (δ-ferrite and austenite), but became more homogeneous in morphology and composition. Different dendrites morphology in the particular regions of the molten layer was confirmed - fine equiaxed dendrites on the top surface and columnar at the bottom of the molten pool. Delta-ferrite is located in the interdendritic areas and in larger amounts in the transition zone between the molten.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"55 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139450853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"STUDYING THE SOLUBILITY OF THE SYSTEM ZnSO4 - KNO3 - H2O","authors":"Dilnoza Ne’matjon qizi Makhkamova, Zokirjon Turayev","doi":"10.59957/jctm.v59.i1.2024.16","DOIUrl":"https://doi.org/10.59957/jctm.v59.i1.2024.16","url":null,"abstract":"The solubility of the components in the ZnSO4 - KNO3 - H2O system was studied by the visual-polythermal method in the temperature range from -7.0°С to 42.0°С. The phase diagram delimits the fields of ice crystallization, KNO3, K2SO4·ZnSO4·6H2O, and ZnSO4. A solubility diagram was constructed, and a new compound K2SO4·ZnSO4·6H2O was separated. The new compound was identified by chemical, X-ray phase, thermogravimetric, and IR spectroscopic analysis.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"18 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139450873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PHYSICAL-CHEMICAL MODELING AND INVESTIGATION OF THE “HIGH-ENTROPY METAL MATRIX / TiC” SYSTEM COMPONENTS INTERACTION","authors":"A. Naizabekov, Marina Samodurova, Evgenii Bodrov, S. Lezhnev, Dmitry Mikhailov, K. Litvinyuk, E. Panin","doi":"10.59957/jctm.v59.i1.2024.25","DOIUrl":"https://doi.org/10.59957/jctm.v59.i1.2024.25","url":null,"abstract":"The research carried out is aimed at developing the scientific basis for obtaining new composite materials based on high-entropy alloys, as well as developing the basic principles of processing and operation of such materials. It was necessary to conduct a theoretical and experimental study of the physical-chemical processes occurring during the interaction of high-entropy alloys with reinforcing TiC particles, as well as to study the effect of temperature and composition of interacting phases on the interaction process and its results. Thermodynamic and kinetic modeling of the interaction processes of the matrix components of high-entropy alloys based on the Cantor alloy (FeCoCrNiMn), including titanium and carbon with the formation of titanium carbide was carried out. Modern modeling approaches were used, which makes it possible to implement modern software. In particular, thermodynamic modeling using methods developed within the framework of the Calphad approach was carried out. Thermo-Calc software (includingTC-PRISMA kinetic modeling software) and FactSage software were used in the research process. An experimental study of the composition and structure of samples of TiC-reinforced metal matrix materials (using electron microscopy, X-ray spectral microanalysis and XRD) was also carried out. The distribution of various elements in the microstructure of materials and their phase composition were investigated. Comparison of the simulation results with experimental data allowed to make conclusions about the qualitative adequacy of thermodynamic and kinetic models of phase equilibria and phase transformations occurring during the formation, possible heat treatment and operation of TiC-reinforced metal matrix materials at high temperatures to the observed experimental data.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"49 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139451001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COTINUS COGGYGRIA ETHANOL EXTRACT AS CROSSLINKING AGENT IN FORMULATION OF THE PROTEIN FILMS","authors":"Ayten Solak, S. Dyankova","doi":"10.59957/jctm.v59.i1.2024.4","DOIUrl":"https://doi.org/10.59957/jctm.v59.i1.2024.4","url":null,"abstract":"The study explores the potential application of smoketree (Cotinus coggygria Scop) ethanol extract (STE) as a natural cross-linking and active component in the formulation of films based on collagen (CL), gelatin (GL) and soy protein isolate (SPI). After casting and drying of the respective film-forming solutions, elastic and homogeneous films were obtained. A significant color difference was found for all protein films with added STE compared to the control series (mainly due to an increase in yellowness). The degree of cross-linking was highest in CLSTE (60 %), followed by GLSTE (27 %) and SPISTE (18 %). The antioxidant activity of the films, determined by the DPPH radical scavenging assay, increased significantly after the addition of STE. The observed increase in tensile strength (TS) for the films with STE ranged from double (CLSTE and SPISTE) to more than 4 times (GLSTE). In addition, there was a significant improvement in the light barrier properties of the extract-incorporated films, but also a reduction in their transparency up to 1.5 times compared to their respective controls. No significant influence was observed on physical characteristics such as thickness, moisture absorption and total soluble matter. Research results show that STE can be successfully used as a natural cross-linking agent in protein films, resulting in improved light barrier properties as well as increased strength and antioxidant activity.","PeriodicalId":38363,"journal":{"name":"Journal of Chemical Technology and Metallurgy","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139451078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}