B. Rakhadilov, L. Bayatanova, A. Kengesbekov, S. Abdulina, M. Kylyshkanov, M.A. Podoynikov, G.S. Moldabayeva
Preliminary studies of fluoranhydrite as a binder showed that on its own it almost does not harden, intervention in the technological process of basic production is almost impossible, so in order to obtain materials it is necessary to develop ways of modifying it to initiate the binder properties or use “acidic” fluoranhydrite before the neutralization stage. In this work the influence of various additives (sodium sulfate and sodium sulfite, potassium sulfate, copper sulfate, iron sulfate crystallohydrate, alumina aluminate, sodium carbonate) on the properties of fluorine hydrite binders produced by neutralization of sour waste from hydrofluoric acid production with an excess of limestone was studied. In this work to obtain dependences of anhydrite binder technological properties on the number of introduced additives and determine the optimal composition of the binder, as well as create mathematical models of the processes under study and their statistical analysis used mathematical planning of the experiment. As the conducted studies showed the speed of setting of products based on anhydrite binder and their strength mainly depend on the temperature of water and its amount for mixing at the optimum dispersity of the binder. The strength of the samples made from the neutralized waste was found to be in the range of 0.5‒1.2 MPa, and the strength of the samples based on the activated anhydrite binder ― in the range of 5.3‒10.7 MPa that corresponds to the parameters of the material suitable for the production of boards.
{"title":"Activation of fluoranhydrite with various chemical additives for the production of gypsum fiberboards","authors":"B. Rakhadilov, L. Bayatanova, A. Kengesbekov, S. Abdulina, M. Kylyshkanov, M.A. Podoynikov, G.S. Moldabayeva","doi":"10.31489/2024ph1/34-42","DOIUrl":"https://doi.org/10.31489/2024ph1/34-42","url":null,"abstract":"Preliminary studies of fluoranhydrite as a binder showed that on its own it almost does not harden, intervention in the technological process of basic production is almost impossible, so in order to obtain materials it is necessary to develop ways of modifying it to initiate the binder properties or use “acidic” fluoranhydrite before the neutralization stage. In this work the influence of various additives (sodium sulfate and sodium sulfite, potassium sulfate, copper sulfate, iron sulfate crystallohydrate, alumina aluminate, sodium carbonate) on the properties of fluorine hydrite binders produced by neutralization of sour waste from hydrofluoric acid production with an excess of limestone was studied. In this work to obtain dependences of anhydrite binder technological properties on the number of introduced additives and determine the optimal composition of the binder, as well as create mathematical models of the processes under study and their statistical analysis used mathematical planning of the experiment. As the conducted studies showed the speed of setting of products based on anhydrite binder and their strength mainly depend on the temperature of water and its amount for mixing at the optimum dispersity of the binder. The strength of the samples made from the neutralized waste was found to be in the range of 0.5‒1.2 MPa, and the strength of the samples based on the activated anhydrite binder ― in the range of 5.3‒10.7 MPa that corresponds to the parameters of the material suitable for the production of boards.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"159 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235491","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}
L. Sulyubayeva, B. Rakhadilov, Y. Naimankumaruly, M.B. Bayandinova, N. Muktanova, N. Berdimuratov
One of the important aspects is the interaction of plasma with the surface of a material, especially in the conditions of a fusion facility. The current work presents the preliminary results of the study of tungsten surface structure modification under helium plasma irradiation. A small-sized linear simulator KAZ-PSI with a plasma-beam setup was designed and assembled, where helium was used as a working gas. The main elements of the linear plasma simulator are an electron beam gun with a LaB6 cathode, a plasma-beam discharge chamber, an interaction chamber, a target device, and an electromagnetic system consisting of electromagnetic coils. It was revealed that under irradiation on the surface of the samples there is a relief with defective structure consisting of chaotically arranged ledges and pits of various shapes with average size (100‒600) nm and pore sizes (0.1‒1.5) μm with visible areas of flaking and sputtering. It was found that when the negative potential on the target is varied by –500V/–1000V/–1500V, the formation of dislocation with chaotic and cellular structure of tungsten with an average grain size of (1‒25) μm is observed; it was revealed that the total values of elastic and plastic components of deformation across the tungsten grain differ from each other by about 2.5 times.
{"title":"Study of changes in the surface structure of tungsten irradiated by helium plasma","authors":"L. Sulyubayeva, B. Rakhadilov, Y. Naimankumaruly, M.B. Bayandinova, N. Muktanova, N. Berdimuratov","doi":"10.31489/2024ph1/23-33","DOIUrl":"https://doi.org/10.31489/2024ph1/23-33","url":null,"abstract":"One of the important aspects is the interaction of plasma with the surface of a material, especially in the conditions of a fusion facility. The current work presents the preliminary results of the study of tungsten surface structure modification under helium plasma irradiation. A small-sized linear simulator KAZ-PSI with a plasma-beam setup was designed and assembled, where helium was used as a working gas. The main elements of the linear plasma simulator are an electron beam gun with a LaB6 cathode, a plasma-beam discharge chamber, an interaction chamber, a target device, and an electromagnetic system consisting of electromagnetic coils. It was revealed that under irradiation on the surface of the samples there is a relief with defective structure consisting of chaotically arranged ledges and pits of various shapes with average size (100‒600) nm and pore sizes (0.1‒1.5) μm with visible areas of flaking and sputtering. It was found that when the negative potential on the target is varied by –500V/–1000V/–1500V, the formation of dislocation with chaotic and cellular structure of tungsten with an average grain size of (1‒25) μm is observed; it was revealed that the total values of elastic and plastic components of deformation across the tungsten grain differ from each other by about 2.5 times.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"192 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235460","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}
S. Katsyv, V. Kukharchuk, V. Madyarov, V. Kucheruk, P.I Kulakov, M.L. Hribov
The paper proposes the use of the non-Euclidean metric to reduce the uncertainty that occurs when measuring voltage for the tasks of ongoing continuous control of electric power consumption in large, branched high-voltage electric networks. The problem is that for continuous control of electric power consumption, it is necessary to install the active and reactive power measuring equipment in each node of the electric network (at each substation) and to ensure the transmission of measurement information to dispatching control centers. For countries with large electric networks, long distances between electric grid nodes and dispatch control centers, this requires huge capital costs. Therefore, it is advisable to place equipment for measuring electric power and voltage only in individual nodes of the electrical network, and then calculate the parameters of the remaining nodes based on Kirchhoff's laws. But at the same time, there is a significant measurement uncertainty, because the complex value of the voltage is usually not measured, only the modulus of the voltage values is used for the calculation. The use of non-Euclidean metrics provides the reduction of the input data uncertainty, which are necessary to control the consumption of electric power in each node of the electric network.
{"title":"Application of non-Euclidean metric in the electric power industry for reduction of measurement uncertainty","authors":"S. Katsyv, V. Kukharchuk, V. Madyarov, V. Kucheruk, P.I Kulakov, M.L. Hribov","doi":"10.31489/2024ph1/83-91","DOIUrl":"https://doi.org/10.31489/2024ph1/83-91","url":null,"abstract":"The paper proposes the use of the non-Euclidean metric to reduce the uncertainty that occurs when measuring voltage for the tasks of ongoing continuous control of electric power consumption in large, branched high-voltage electric networks. The problem is that for continuous control of electric power consumption, it is necessary to install the active and reactive power measuring equipment in each node of the electric network (at each substation) and to ensure the transmission of measurement information to dispatching control centers. For countries with large electric networks, long distances between electric grid nodes and dispatch control centers, this requires huge capital costs. Therefore, it is advisable to place equipment for measuring electric power and voltage only in individual nodes of the electrical network, and then calculate the parameters of the remaining nodes based on Kirchhoff's laws. But at the same time, there is a significant measurement uncertainty, because the complex value of the voltage is usually not measured, only the modulus of the voltage values is used for the calculation. The use of non-Euclidean metrics provides the reduction of the input data uncertainty, which are necessary to control the consumption of electric power in each node of the electric network.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"5 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235561","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}
N. Tanasheva, A. Bakhtybekova, N. Shuyushbayeva, A. Dyusembaeva, M.A. Burkov, S.A. Nurkenov
Magnus wind turbines have a number of advantages in the form of electricity generation at low wind values, ranging from 3-4 m/s. However, at high speeds around the existing blades of wind turbines, there is a phenomenon of separation of vortices, which entails the destruction of the structure, as well as an increase in drag. Based on this, an urgent issue is the regulation of the flow around cylindrical bodies, along with a decrease in drag force. The novelty of the work is the elimination of vortices, as well as their control, by adding a fixed blade to the cylinder. Authors of the article for this purpose created a mock-up of the cylinder blade with a fixed blade. A number of experimental studies were carried out to determine the aerodynamic forces and coefficients depending on the angle of inclination with respect to the incoming flow at U = 5 m/s. It was found that at an angle of inclination of 0° and 180°, the combined blade has a maximum lifting force of 2.7 N and 2.75 N, respectively. It is determined that at these angles, the drag force is the lowest and is 1.26 N and 1.08 N.
马格努斯风力涡轮机在低风速（3-4 米/秒）发电方面具有许多优势。然而，在现有风力涡轮机叶片周围高速旋转时，会出现涡流分离现象，导致结构破坏和阻力增加。因此，当务之急是调节圆柱体周围的气流，同时降低阻力。这项工作的新颖之处在于通过在圆柱体上添加固定叶片来消除和控制涡流。为此，文章作者制作了一个带有固定叶片的圆柱体叶片模型。进行了大量实验研究，以确定空气动力和系数，这取决于相对于 U = 5 m/s 入流的倾斜角度。研究发现，在倾角为 0° 和 180° 时，组合叶片的最大提升力分别为 2.7 N 和 2.75 N。在这些角度下，阻力最小，分别为 1.26 N 和 1.08 N。
{"title":"Experimental study of aerodynamic coefficients of a combined blade","authors":"N. Tanasheva, A. Bakhtybekova, N. Shuyushbayeva, A. Dyusembaeva, M.A. Burkov, S.A. Nurkenov","doi":"10.31489/2024ph1/92-98","DOIUrl":"https://doi.org/10.31489/2024ph1/92-98","url":null,"abstract":"Magnus wind turbines have a number of advantages in the form of electricity generation at low wind values, ranging from 3-4 m/s. However, at high speeds around the existing blades of wind turbines, there is a phenomenon of separation of vortices, which entails the destruction of the structure, as well as an increase in drag. Based on this, an urgent issue is the regulation of the flow around cylindrical bodies, along with a decrease in drag force. The novelty of the work is the elimination of vortices, as well as their control, by adding a fixed blade to the cylinder. Authors of the article for this purpose created a mock-up of the cylinder blade with a fixed blade. A number of experimental studies were carried out to determine the aerodynamic forces and coefficients depending on the angle of inclination with respect to the incoming flow at U = 5 m/s. It was found that at an angle of inclination of 0° and 180°, the combined blade has a maximum lifting force of 2.7 N and 2.75 N, respectively. It is determined that at these angles, the drag force is the lowest and is 1.26 N and 1.08 N.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"151 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235638","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}
I. Spivak-Lavrov, S. Sharipov, A.B. Seiten, A.A. Trubitsyn
Deflector plates consist of two parallel conductive plates that create a deflecting electric field. They can be used to control the flow of charged particles ― electrons or ions. The effect of the еdgе fiеld of deflector plates leads to a change in the velocity of charged particles in the longitudinal and transverse directions, consequently of which their real trajectories change, deviating from ideal ones, which violates the space-time resolution of corpuscular optical devices in which they are used. Apart from that, the electric field at the input to the plates of deflector can vary over time, which must also be taken into account when the deflector diverts the beam of charged particles. Thus, in many cases, the use of deflector plates with open ends is inappropriate, since uncontrolled scattering fields are formed. In this article, we can consider the field of deflector plates with expanded screens at the output, so that deflecting beams of charged particles can be used at the output of deflector plates. Using the methods of the theory of complex variable functions, analytical expressions for the edge field of deflector plates with grounded screens were obtained. Firstly, by grounding the screens and shielding the plates from the deflection field, we can localize the edge electric field and reduce the uncontrolled scattering fields, and secondly, such a field can be accurately calculated analytically.
{"title":"Еdgе fiеld of dеflеctorplаtes with expanding screens","authors":"I. Spivak-Lavrov, S. Sharipov, A.B. Seiten, A.A. Trubitsyn","doi":"10.31489/2024ph1/99-105","DOIUrl":"https://doi.org/10.31489/2024ph1/99-105","url":null,"abstract":"Deflector plates consist of two parallel conductive plates that create a deflecting electric field. They can be used to control the flow of charged particles ― electrons or ions. The effect of the еdgе fiеld of deflector plates leads to a change in the velocity of charged particles in the longitudinal and transverse directions, consequently of which their real trajectories change, deviating from ideal ones, which violates the space-time resolution of corpuscular optical devices in which they are used. Apart from that, the electric field at the input to the plates of deflector can vary over time, which must also be taken into account when the deflector diverts the beam of charged particles. Thus, in many cases, the use of deflector plates with open ends is inappropriate, since uncontrolled scattering fields are formed. In this article, we can consider the field of deflector plates with expanded screens at the output, so that deflecting beams of charged particles can be used at the output of deflector plates. Using the methods of the theory of complex variable functions, analytical expressions for the edge field of deflector plates with grounded screens were obtained. Firstly, by grounding the screens and shielding the plates from the deflection field, we can localize the edge electric field and reduce the uncontrolled scattering fields, and secondly, such a field can be accurately calculated analytically.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":" 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140391231","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}
The creation of a laboratory installation was carried out with an aim to ensure the study of the working processes and characteristics of vacuum boosters as a part of hydraulic brake drives for vehicles with a gross weight of up to 3.5 tons for civilian usage, and armored vehicles with a gross weight of up to 8.5 tons designated for service and combat missions. Theoretical researches in this direction have been previously carried out by a number of scientists of the Department of “Automobiles” named after prof. Gredeskul A.B. in Kharkiv National Automobile and Road University, the results of which have been highlighted in a number of scientific papers. Comparison of the results of theoretical studies with the experimental ones, received on the laboratory setup and suggested in this paper, according to the experimental method described in the article, using the created electronic signal processing complex and sensor unit, made it possible to establish a discrepancy between theoretical and experimental studies within 6%. This complex for experimental research was created for the first time, thus allowing to obtain the results that confirm the theoretical studies of the vacuum boosters of the brake drive of cars, as well as revealed a number of dependencies between the weight and overall parameters of the under research unit, along with the number of functional relationships between the structural components of the vacuum boosters, which enables to significantly optimize its design.
{"title":"Research of the vacuum brake booster working process","authors":"N.V Sklyarov, A.I. Shapovalov, P.V. Chernenko, A.V Korniev, A.A. Kashkanov, V.A. Kashkanov, V. Kucheruk","doi":"10.31489/2024ph1/43-58","DOIUrl":"https://doi.org/10.31489/2024ph1/43-58","url":null,"abstract":"The creation of a laboratory installation was carried out with an aim to ensure the study of the working processes and characteristics of vacuum boosters as a part of hydraulic brake drives for vehicles with a gross weight of up to 3.5 tons for civilian usage, and armored vehicles with a gross weight of up to 8.5 tons designated for service and combat missions. Theoretical researches in this direction have been previously carried out by a number of scientists of the Department of “Automobiles” named after prof. Gredeskul A.B. in Kharkiv National Automobile and Road University, the results of which have been highlighted in a number of scientific papers. Comparison of the results of theoretical studies with the experimental ones, received on the laboratory setup and suggested in this paper, according to the experimental method described in the article, using the created electronic signal processing complex and sensor unit, made it possible to establish a discrepancy between theoretical and experimental studies within 6%. This complex for experimental research was created for the first time, thus allowing to obtain the results that confirm the theoretical studies of the vacuum boosters of the brake drive of cars, as well as revealed a number of dependencies between the weight and overall parameters of the under research unit, along with the number of functional relationships between the structural components of the vacuum boosters, which enables to significantly optimize its design.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"161 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235618","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}
N. Berdimuratov, Y. Kambarov, M. Maulet, S.D. Bolatov, Zh.B. Sagdoldina, D. Baizhan
This paper presents the results of research aimed at developing the technology of plow share hardening by means of electrofriction hardening. It is shown that in electrofriction hardening of plow shares a structure with microhardness gradient is formed along the depth of the hardened zone. After electrofriction hardening the microhardness of plow share increases in 3–3.5 times in comparison with the initial state. The reason for the gradient character of microhardness distribution along the thickness of the modified layer is the ultra-high cooling rate, which causes a high temperature gradient near the surface. On the basis of the results of scanning electron microscopy it is established that at electrofriction hardening of steel 40Kh the hardened surface layer is formed, consisting of two zones: the surface hardened zone with the structure of fine–needle martensite and austenite; the zone of thermal influence (transition layer) with martensite-perlite structure, smoothly passing into the initial ferrite-perlite structure. It is established that the phase composition of steel 40Kh in the initial state consists of α-Fe phase with BCC lattice, and after electrofriction hardening the hardening phases of residual austenite (γ-Fe) and martensite (α'-Fe) are formed. The obtained data allow us to conclude that electrofriction treatment is an effective method of plow share hardening from structural steel 40Kh.
{"title":"Electrofriction treatment of plow shares","authors":"N. Berdimuratov, Y. Kambarov, M. Maulet, S.D. Bolatov, Zh.B. Sagdoldina, D. Baizhan","doi":"10.31489/2024ph1/66-72","DOIUrl":"https://doi.org/10.31489/2024ph1/66-72","url":null,"abstract":"This paper presents the results of research aimed at developing the technology of plow share hardening by means of electrofriction hardening. It is shown that in electrofriction hardening of plow shares a structure with microhardness gradient is formed along the depth of the hardened zone. After electrofriction hardening the microhardness of plow share increases in 3–3.5 times in comparison with the initial state. The reason for the gradient character of microhardness distribution along the thickness of the modified layer is the ultra-high cooling rate, which causes a high temperature gradient near the surface. On the basis of the results of scanning electron microscopy it is established that at electrofriction hardening of steel 40Kh the hardened surface layer is formed, consisting of two zones: the surface hardened zone with the structure of fine–needle martensite and austenite; the zone of thermal influence (transition layer) with martensite-perlite structure, smoothly passing into the initial ferrite-perlite structure. It is established that the phase composition of steel 40Kh in the initial state consists of α-Fe phase with BCC lattice, and after electrofriction hardening the hardening phases of residual austenite (γ-Fe) and martensite (α'-Fe) are formed. The obtained data allow us to conclude that electrofriction treatment is an effective method of plow share hardening from structural steel 40Kh.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235322","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}
M. Kubenova, K. Kuterbekov, M. Balapanov, R. Ishembetov, G. D. Kabdrakhimova, R. Alina, M. Tatay, R. Ildos
Modern research efforts are aimed at developing fuel cells characterized by high efficiency, low cost and environmental friendliness, which largely depend on the properties of the corresponding catalyst materials ― the most important components of the fuel cell. Catalysts based on metal chalcogenides, predominantly S based, have activity in accelerating the oxygen reduction reaction comparable to the activity of Pt in H2SO4. The work uses the technique of compacting powder materials and obtained volumetric samples. Nanodisperse powder fractions with an average particle size of (50–100) nm were obtained. The values of the thermo-emf coefficient (about 0.08 mV/K) were obtained for the studied alloy with low defects in the cation sublattice of the Сu2S0.5Te0.5 type. It was found that a decrease in grain size leads to a significant decrease in electronic conductivity for all studied samples. The paper presents the results of a study of the thermoelectric properties of the Cu2S0.5Te0.5 triple alloy. For the studied composition, a decrease in thermal conductivity by (25‒30)% and a slight increase in the thermal emf coefficient compared with large–crystal samples were obtained. Low thermal conductivity was found in the range (0.3–1.1) W m-1 K-1 with a conductivity above 1000 ohms-1cm-1. For the studied sample Cu2S0.5Te0.5 ― thermoelectric efficiency (ZT = 0.25) at 400 °C, which allows us to hope for the possibility of improving the characteristics of samples of this composition to acceptable values for practical thermoelectric devices by selecting the optimal alloying.
现代研究的目标是开发高效、低成本和环保的燃料电池，这在很大程度上取决于相应催化剂材料的特性，而催化剂材料是燃料电池最重要的组成部分。基于金属卤化物（主要是 S 基）的催化剂在加速氧还原反应方面的活性可与 H2SO4 中铂的活性相媲美。这项研究采用了粉末材料压制技术，并获得了体积样品。获得了平均粒径为（50-100）纳米的纳米分散粉末馏分。所研究的Сu2S0.5Te0.5 型合金的阳离子亚晶格缺陷较低，因此获得了热电系数（约 0.08 mV/K）。研究发现，晶粒尺寸的减小会导致所有研究样品的电子电导率显著降低。本文介绍了 Cu2S0.5Te0.5 三元合金的热电性能研究结果。就所研究的成分而言，与大晶体样品相比，热导率降低了 (25-30)%，热辐射系数略有增加。热导率在 (0.3-1.1) W m-1 K-1 范围内较低，电导率高于 1000 欧姆-1 厘米-1。所研究的样品 Cu2S0.5Te0.5 - 400 °C 时的热电效率（ZT = 0.25），这使我们有希望通过选择最佳合金来改善这种成分样品的特性，使其达到实用热电设备的可接受值。
{"title":"Investigation of thermoelectric properties of nanocrystalline copper chalcogenides","authors":"M. Kubenova, K. Kuterbekov, M. Balapanov, R. Ishembetov, G. D. Kabdrakhimova, R. Alina, M. Tatay, R. Ildos","doi":"10.31489/2024ph1/59-65","DOIUrl":"https://doi.org/10.31489/2024ph1/59-65","url":null,"abstract":"Modern research efforts are aimed at developing fuel cells characterized by high efficiency, low cost and environmental friendliness, which largely depend on the properties of the corresponding catalyst materials ― the most important components of the fuel cell. Catalysts based on metal chalcogenides, predominantly S based, have activity in accelerating the oxygen reduction reaction comparable to the activity of Pt in H2SO4. The work uses the technique of compacting powder materials and obtained volumetric samples. Nanodisperse powder fractions with an average particle size of (50–100) nm were obtained. The values of the thermo-emf coefficient (about 0.08 mV/K) were obtained for the studied alloy with low defects in the cation sublattice of the Сu2S0.5Te0.5 type. It was found that a decrease in grain size leads to a significant decrease in electronic conductivity for all studied samples. The paper presents the results of a study of the thermoelectric properties of the Cu2S0.5Te0.5 triple alloy. For the studied composition, a decrease in thermal conductivity by (25‒30)% and a slight increase in the thermal emf coefficient compared with large–crystal samples were obtained. Low thermal conductivity was found in the range (0.3–1.1) W m-1 K-1 with a conductivity above 1000 ohms-1cm-1. For the studied sample Cu2S0.5Te0.5 ― thermoelectric efficiency (ZT = 0.25) at 400 °C, which allows us to hope for the possibility of improving the characteristics of samples of this composition to acceptable values for practical thermoelectric devices by selecting the optimal alloying.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"39 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235244","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}
A. Zhumabekov, A. Kassanova, N. Ispulov, K. Dossumbekov, Zh. Ospanova, T. Dossanov, A. Kurmanov
The influence of reduced graphene oxide and the optoelectronic characterictics of a nanocomposites based on rGO and TiO2 were studied. Surface morphology and Raman spectra of nanocomposite materials indicate the presence of initial components. It has been illustrated that during hydrothermal synthesis further reduction of rGO occurs, i.e. the variety of oxygen-containing groups decreases. Studies of current-voltage characteristics have displayed the availability of rGO in the nanocomposite leads to an increase in the photo induced current to more than 40 µA. Next, the photoresponsivity of the samples was determined, which is three orders of value higher than pure titanium dioxide for nano-composite material. And the detectivity also increased 9 times. This parameter allows you to identify the performance of the device. In this regard, the UV detector based on nanocomposite has a higher performance. Studies also show a decrease in reaction time to light irradiation. When irradiated, the nanocomposite material reacts to light three orders of magnitude faster than TiO2.
{"title":"High responsivity UV detector based on TiO2-rGO nanocomposite material","authors":"A. Zhumabekov, A. Kassanova, N. Ispulov, K. Dossumbekov, Zh. Ospanova, T. Dossanov, A. Kurmanov","doi":"10.31489/2024ph1/6-12","DOIUrl":"https://doi.org/10.31489/2024ph1/6-12","url":null,"abstract":"The influence of reduced graphene oxide and the optoelectronic characterictics of a nanocomposites based on rGO and TiO2 were studied. Surface morphology and Raman spectra of nanocomposite materials indicate the presence of initial components. It has been illustrated that during hydrothermal synthesis further reduction of rGO occurs, i.e. the variety of oxygen-containing groups decreases. Studies of current-voltage characteristics have displayed the availability of rGO in the nanocomposite leads to an increase in the photo induced current to more than 40 µA. Next, the photoresponsivity of the samples was determined, which is three orders of value higher than pure titanium dioxide for nano-composite material. And the detectivity also increased 9 times. This parameter allows you to identify the performance of the device. In this regard, the UV detector based on nanocomposite has a higher performance. Studies also show a decrease in reaction time to light irradiation. When irradiated, the nanocomposite material reacts to light three orders of magnitude faster than TiO2.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"187 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235765","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}
M. Kubenova, K. Kuterbekov, M. Balapanov, R. Ishembetov, G. D. Kabdrakhimova, R. Alina, M. Tatay, R. Ildos
Copper chalcogenides have a complex electronic structure due to the interaction of hybridized s- and p-states of chalcogen forming a valence band with 3d states of copper, which greatly complicates the interpretation of temperature dependences of kinetic parameters having a nonmonotonic character. Cu2S copper sulfide is an effective thermoelectric material, so it is interesting to study its kinetic parameters of solid solutions that it forms with alkali metals. The nonstoichiometry of chalcogenides can be easily controlled electrochemically, therefore, the task of selecting the optimal composition according to the cationic sublattice is quite feasible. The paper presents experimental studies of the properties of Cu2S binary copper sulfide. Copper chalcogenides have a complex electronic structure due to the interaction of hybridized s- and p-states of chalcogen forming a valence band with 3d states of copper, which greatly complicates the interpretation of temperature dependences of kinetic parameters having a nonmonotonic character. For the Cu2S sample, rather low values of the electron thermal EMF coefficient of the sample from 0.05 mV/K to 0.25 mV/K were found, which are more typical for metals than for semiconductors. The thermal conductivity of the Cu2S sample is quite low, it rises to 0.3 W/m*K at a phase transition of about 380 K and does not fall below 0.2 W/m*K. Thus, the nonstoichiometry of chalcogenides can be easily controlled electrochemically, therefore, the task of selecting the optimal composition according to the cationic sublattice is quite feasible. In addition, to improve the thermoelectric properties of Cu2S, it can be achieved by alloying alkali metals into a binary copper sulfide matrix.
卤化铜具有复杂的电子结构，这是由于卤化铜的杂化 s 态和 p 态与铜的 3d 态相互作用形成了价带，这使得对具有非单调特性的动力学参数的温度依赖性的解释变得非常复杂。硫化铜 Cu2S 是一种有效的热电材料，因此研究它与碱金属形成的固溶体的动力学参数很有意义。氢化铝的非几何形状很容易通过电化学方法进行控制，因此，根据阳离子亚晶格选择最佳成分是非常可行的。本文介绍了对 Cu2S 二元硫化铜特性的实验研究。卤化铜具有复杂的电子结构，这是因为卤化铜的杂化 s 态和 p 态与铜的 3d 态相互作用形成了价带，这使得对具有非单调特性的动力学参数的温度依赖性的解释变得非常复杂。在 Cu2S 样品中，发现样品的电子热 EMF 系数在 0.05 mV/K 至 0.25 mV/K 之间，数值较低，这在金属中比在半导体中更为典型。Cu2S 样品的热导率相当低，在约 380 K 的相变过程中升至 0.3 W/m*K，且不会低于 0.2 W/m*K。因此，可以很容易地通过电化学方法控制钙钛矿的非化学计量，因此，根据阳离子亚晶格选择最佳成分的任务是相当可行的。此外，为了改善 Cu2S 的热电特性，还可以在二元硫化铜基体中加入碱金属合金。
{"title":"Thermal properties of Cu2S binary copper sulfides","authors":"M. Kubenova, K. Kuterbekov, M. Balapanov, R. Ishembetov, G. D. Kabdrakhimova, R. Alina, M. Tatay, R. Ildos","doi":"10.31489/2024ph1/13-22","DOIUrl":"https://doi.org/10.31489/2024ph1/13-22","url":null,"abstract":"Copper chalcogenides have a complex electronic structure due to the interaction of hybridized s- and p-states of chalcogen forming a valence band with 3d states of copper, which greatly complicates the interpretation of temperature dependences of kinetic parameters having a nonmonotonic character. Cu2S copper sulfide is an effective thermoelectric material, so it is interesting to study its kinetic parameters of solid solutions that it forms with alkali metals. The nonstoichiometry of chalcogenides can be easily controlled electrochemically, therefore, the task of selecting the optimal composition according to the cationic sublattice is quite feasible. The paper presents experimental studies of the properties of Cu2S binary copper sulfide. Copper chalcogenides have a complex electronic structure due to the interaction of hybridized s- and p-states of chalcogen forming a valence band with 3d states of copper, which greatly complicates the interpretation of temperature dependences of kinetic parameters having a nonmonotonic character. For the Cu2S sample, rather low values of the electron thermal EMF coefficient of the sample from 0.05 mV/K to 0.25 mV/K were found, which are more typical for metals than for semiconductors. The thermal conductivity of the Cu2S sample is quite low, it rises to 0.3 W/m*K at a phase transition of about 380 K and does not fall below 0.2 W/m*K. Thus, the nonstoichiometry of chalcogenides can be easily controlled electrochemically, therefore, the task of selecting the optimal composition according to the cationic sublattice is quite feasible. In addition, to improve the thermoelectric properties of Cu2S, it can be achieved by alloying alkali metals into a binary copper sulfide matrix.","PeriodicalId":505293,"journal":{"name":"Bulletin of the Karaganda University \"Physics Series\"","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235299","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}
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