Pub Date : 2023-07-26DOI: 10.26896/1028-6861-2023-89-7-71-77
S. I. Safin, V. Tolcheev
One of the most important tasks in Text Mining is the formation of sufficiently large representative and consistent samples (datasets). Usually, datasets are obtained from various information sources. In some cases, due to the lack of specialized texts in Russian, the dataset is expanded by adding translated English-language documents. In such situations, it is advisable to evaluate the uniformity-heterogeneity of the combined arrays. However, such a verification is complicated by the fact that the documents are multidimensional vectors, the correct comparison of which is a very non-trivial task. Insufficient elaboration of procedures for checking the uniformity of samples for the multidimensional case leads to the fact the problem of possible differences in data is ignored that in practice as insignificant. As a result, classifiers are trained on samples that are a mixture of quite diverse texts, and the resulting quality of categorization does not improve (or even deteriorates). Thus, it seems relevant to develop a procedure for checking the uniformity of documentary samples. To do this, we provide a comprehensive study of the problem of shift in textual data, identified and analyzed the reasons that cause the heterogeneity of documentary arrays. In this study, the datasets consist of bibliographic descriptions of scientific articles (title, abstract, keywords). The authors develop a procedure for assessing the homogeneity of two samples having approximately the same volume and the same method for calculating the weights of terms. For comparison, centroids are used, which have the size of a common dictionary of two datasets (in the absence of some terms, zero values are put in the corresponding positions of the centroids). The representation of samples in the form of «terminological portraits» (centroids) allowed us to reduce the verification of the homogeneity of multidimensional document vectors to a well-studied problem of analyzing two one-dimensional connected samples, for which nonparametric criteria were used. The sign criterion and the Wilcoxon sign rank criterion were used in the study. The proposed procedure for checking the uniformity of samples was tested on three collections of documents obtained from Russian and English-language sources.
{"title":"Procedure for checking the uniformity of samples of text documents based on nonparametric criteria","authors":"S. I. Safin, V. Tolcheev","doi":"10.26896/1028-6861-2023-89-7-71-77","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-71-77","url":null,"abstract":"One of the most important tasks in Text Mining is the formation of sufficiently large representative and consistent samples (datasets). Usually, datasets are obtained from various information sources. In some cases, due to the lack of specialized texts in Russian, the dataset is expanded by adding translated English-language documents. In such situations, it is advisable to evaluate the uniformity-heterogeneity of the combined arrays. However, such a verification is complicated by the fact that the documents are multidimensional vectors, the correct comparison of which is a very non-trivial task. Insufficient elaboration of procedures for checking the uniformity of samples for the multidimensional case leads to the fact the problem of possible differences in data is ignored that in practice as insignificant. As a result, classifiers are trained on samples that are a mixture of quite diverse texts, and the resulting quality of categorization does not improve (or even deteriorates). Thus, it seems relevant to develop a procedure for checking the uniformity of documentary samples. To do this, we provide a comprehensive study of the problem of shift in textual data, identified and analyzed the reasons that cause the heterogeneity of documentary arrays. In this study, the datasets consist of bibliographic descriptions of scientific articles (title, abstract, keywords). The authors develop a procedure for assessing the homogeneity of two samples having approximately the same volume and the same method for calculating the weights of terms. For comparison, centroids are used, which have the size of a common dictionary of two datasets (in the absence of some terms, zero values are put in the corresponding positions of the centroids). The representation of samples in the form of «terminological portraits» (centroids) allowed us to reduce the verification of the homogeneity of multidimensional document vectors to a well-studied problem of analyzing two one-dimensional connected samples, for which nonparametric criteria were used. The sign criterion and the Wilcoxon sign rank criterion were used in the study. The proposed procedure for checking the uniformity of samples was tested on three collections of documents obtained from Russian and English-language sources.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86664464","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}
Pub Date : 2023-07-26DOI: 10.26896/1028-6861-2023-89-7-61-70
R. I. Solovyov, A. Safin, D. Balkaev, V. V. Batrakov, L. Amirova
The shaping of composite consolidated plates into products is a complex process. To obtain a defect-free product, we have to bear in mind that thermoplastics reinforced with a fabric practically do not stretch, and their shaping behavior is determined by the mechanisms of shear deformations within a layer or between layers, by the processes of sliding a composite over the surface of tooling and by the flexural rigidity of the consolidated plates. Due to the complex behavior of the material during deformation, the optimization of the thermoforming process by trial and error is rather expensive in implementation and can be successfully replaced by a preliminary simulation. The available software packages intended for modeling the thermoforming process which provide construction of a correct model of the material consistent with the reality, require the introduction of input parameters for the drape of the consolidated plate, its flexural stiffness, the coefficient of friction between layers and with tooling. However, until now there are no standards for their measurement, which significantly hinders the process of modeling the thermoforming of products from consolidated plates based on thermoplastic binders. We present experimental data on the determination of some physical and mechanical properties of carbon fiber reinforced plastics based on polypropylene PP01030, including tensile-displacement tests of the sample, tests with a moving frame that provide evaluating the shear behavior of thermoplastic composite materials, as well as tests for determining the interlayer friction and friction of a composite with tooling. The tests were carried out at the melting temperature of the matrix using specialized tooling, made taking into account the experience of foreign research groups in physical and mechanical testing of thermoplastic composite materials. A method for determining the flexural rigidity of thermoplastic carbon fiber reinforced plastics is proposed. The presented tooling does not require the application of a complex force, and needs only standard tensile test clamps of the testing machine. The data obtained from the physicomechanical tests can be used in virtual modeling of the thermoforming process of consolidated composite plates.
{"title":"Determination of the shaping behavior of thermoplastic composite materials required for simulation of thermoforming","authors":"R. I. Solovyov, A. Safin, D. Balkaev, V. V. Batrakov, L. Amirova","doi":"10.26896/1028-6861-2023-89-7-61-70","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-61-70","url":null,"abstract":"The shaping of composite consolidated plates into products is a complex process. To obtain a defect-free product, we have to bear in mind that thermoplastics reinforced with a fabric practically do not stretch, and their shaping behavior is determined by the mechanisms of shear deformations within a layer or between layers, by the processes of sliding a composite over the surface of tooling and by the flexural rigidity of the consolidated plates. Due to the complex behavior of the material during deformation, the optimization of the thermoforming process by trial and error is rather expensive in implementation and can be successfully replaced by a preliminary simulation. The available software packages intended for modeling the thermoforming process which provide construction of a correct model of the material consistent with the reality, require the introduction of input parameters for the drape of the consolidated plate, its flexural stiffness, the coefficient of friction between layers and with tooling. However, until now there are no standards for their measurement, which significantly hinders the process of modeling the thermoforming of products from consolidated plates based on thermoplastic binders. We present experimental data on the determination of some physical and mechanical properties of carbon fiber reinforced plastics based on polypropylene PP01030, including tensile-displacement tests of the sample, tests with a moving frame that provide evaluating the shear behavior of thermoplastic composite materials, as well as tests for determining the interlayer friction and friction of a composite with tooling. The tests were carried out at the melting temperature of the matrix using specialized tooling, made taking into account the experience of foreign research groups in physical and mechanical testing of thermoplastic composite materials. A method for determining the flexural rigidity of thermoplastic carbon fiber reinforced plastics is proposed. The presented tooling does not require the application of a complex force, and needs only standard tensile test clamps of the testing machine. The data obtained from the physicomechanical tests can be used in virtual modeling of the thermoforming process of consolidated composite plates.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89808146","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}
Pub Date : 2023-07-26DOI: 10.26896/1028-6861-2023-89-7-51-60
M. Tupitsin, I. A. Trishkina, E. I. Storozheva
The reasons for the premature failure of a spring made of steel 50KhFA used in the safety valve of the column head part of the flare facility were analyzed. The failure of the spring occurred after 7 years of operation at a temperature below 90°C in a working environment of light oil products (sulfurous gasoline). Visual and measurement control, chemical analysis of the steel composition, energy-dispersive X-ray spectroscopy (EDS) of metal in local areas, macro- and microstructural analysis, macro- and electron fractography, phase chemical and X-ray structural analysis, hardness and microhardness tests and reductive heat treatment were used in the research. The data on the characteristic external signs, typical micro damages, and the mechanism of destruction under low-temperature hydrogen sulfide corrosion of steel 50KhFA with hydrogenation, the most dangerous accompanying process, were gained in the study. According to the results obtained, the chemical composition and hardness of the spring metal meet the requirements of the standards for steel 50KhFA. The microstructure of the studied metal is tempered martensite with a decarburized layer up to 0.158 mm in thickness present on the surface. The analysis of the results showed that the premature failure of the spring is attributed both to technological heredity and contact with the working environment unauthorized by the project. An ulcerative damage of the metal surface and penetrating of corrosion products into the depth of metal due to violation of the integrity of the spring coating were revealed, which indicates a low resistance of 50KhFA steel to low-temperature hydrogen sulfide corrosion. The failure occurs predominantly near non-metallic inclusions along the boundaries of primary austenitic grains, where the largest precipitates of chromium carbides are located, as well as along the interphase boundaries of oriented carbide plates.
{"title":"On the reasons for the premature failure of safety valve springs in the equipment of the primary oil refining","authors":"M. Tupitsin, I. A. Trishkina, E. I. Storozheva","doi":"10.26896/1028-6861-2023-89-7-51-60","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-51-60","url":null,"abstract":"The reasons for the premature failure of a spring made of steel 50KhFA used in the safety valve of the column head part of the flare facility were analyzed. The failure of the spring occurred after 7 years of operation at a temperature below 90°C in a working environment of light oil products (sulfurous gasoline). Visual and measurement control, chemical analysis of the steel composition, energy-dispersive X-ray spectroscopy (EDS) of metal in local areas, macro- and microstructural analysis, macro- and electron fractography, phase chemical and X-ray structural analysis, hardness and microhardness tests and reductive heat treatment were used in the research. The data on the characteristic external signs, typical micro damages, and the mechanism of destruction under low-temperature hydrogen sulfide corrosion of steel 50KhFA with hydrogenation, the most dangerous accompanying process, were gained in the study. According to the results obtained, the chemical composition and hardness of the spring metal meet the requirements of the standards for steel 50KhFA. The microstructure of the studied metal is tempered martensite with a decarburized layer up to 0.158 mm in thickness present on the surface. The analysis of the results showed that the premature failure of the spring is attributed both to technological heredity and contact with the working environment unauthorized by the project. An ulcerative damage of the metal surface and penetrating of corrosion products into the depth of metal due to violation of the integrity of the spring coating were revealed, which indicates a low resistance of 50KhFA steel to low-temperature hydrogen sulfide corrosion. The failure occurs predominantly near non-metallic inclusions along the boundaries of primary austenitic grains, where the largest precipitates of chromium carbides are located, as well as along the interphase boundaries of oriented carbide plates.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90611102","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}
Pub Date : 2023-07-26DOI: 10.26896/1028-6861-2023-89-7-78-86
E. Kolesnikov
The analysis the concept of uncertainty, its origin, interpretation in various scientific fields, sources of uncertainty, qualitative and quantitative aspects of this concept, as well as approaches to quantifying uncertainty are presented. Methods of historical and comparative analysis were used in the study. The main conclusion is the necessity of taking into account the presence of uncertainty and quantification of uncertainty of the results of mathematical modeling of objects and phenomena of the surrounding world in the same way as we do when assessing measurement uncertainty of experimental data. In is shown that the interval approach to estimating uncertainty of modeling results currently seems to be the most promising. The concept of uncertainty first proposed at the beginning of the last century refers to epistemic situations involving imperfect or unknown information. This concept had only a qualitative aspect for a long time. In the second half of the twentieth century, almost simultaneously with the development of a risk-based approach in the field of technological security, there was an interest in understanding uncertainty, its origin and typification. We are indebted to metrology for giving uncertainty a quantitative aspect, in which, instead of the measurement error paradigm, a measurement uncertainty paradigm was developed, and approaches (partly controversial) to its quantitative assessment were proposed. Uncertainty is an attribute of any data obtained both experimentally or theoretically (currently, usually by mathematical modeling). In the field of experimental research, specifying the uncertainty interval of the result has long been a scientific standard and routine. The time has come to make it mandatory for the results of theoretical research. To date, three alternative methods of quantitative estimation of uncertainty have been developed: probabilistic, fuzzy and interval methods. Methods for leveling the negative features of its initial «naive» version have been proposed in modern interval analysis. It seems to be the most promising method of quantifying uncertainty of the results of mathematical modeling today.
{"title":"Uncertainty: qualitative and quantitative aspects","authors":"E. Kolesnikov","doi":"10.26896/1028-6861-2023-89-7-78-86","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-78-86","url":null,"abstract":"The analysis the concept of uncertainty, its origin, interpretation in various scientific fields, sources of uncertainty, qualitative and quantitative aspects of this concept, as well as approaches to quantifying uncertainty are presented. Methods of historical and comparative analysis were used in the study. The main conclusion is the necessity of taking into account the presence of uncertainty and quantification of uncertainty of the results of mathematical modeling of objects and phenomena of the surrounding world in the same way as we do when assessing measurement uncertainty of experimental data. In is shown that the interval approach to estimating uncertainty of modeling results currently seems to be the most promising. The concept of uncertainty first proposed at the beginning of the last century refers to epistemic situations involving imperfect or unknown information. This concept had only a qualitative aspect for a long time. In the second half of the twentieth century, almost simultaneously with the development of a risk-based approach in the field of technological security, there was an interest in understanding uncertainty, its origin and typification. We are indebted to metrology for giving uncertainty a quantitative aspect, in which, instead of the measurement error paradigm, a measurement uncertainty paradigm was developed, and approaches (partly controversial) to its quantitative assessment were proposed. Uncertainty is an attribute of any data obtained both experimentally or theoretically (currently, usually by mathematical modeling). In the field of experimental research, specifying the uncertainty interval of the result has long been a scientific standard and routine. The time has come to make it mandatory for the results of theoretical research. To date, three alternative methods of quantitative estimation of uncertainty have been developed: probabilistic, fuzzy and interval methods. Methods for leveling the negative features of its initial «naive» version have been proposed in modern interval analysis. It seems to be the most promising method of quantifying uncertainty of the results of mathematical modeling today.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73686685","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}
Pub Date : 2023-07-26DOI: 10.26896/1028-6861-2023-89-7-34-44
N. Yakovleva, A. N. Kokatev, K. I. Oskin, K. Stepanova, A. Shulga
A widely used nanocomposite coating is a porous anodic alumina colored by particles of metals or their compounds deposited into the pores. The insertion of light-scattering nanosized particles into the pores changes the optical properties of the anodic oxide, whereas the immobilization of metal nanoparticles in pores ensures their corrosion resistance. We present the results of studying black protective and decorative coatings on the surface of AMg5 aluminum alloy. The surface morphology of the samples was analyzed using atomic force microscopy, and the electrophysical properties were monitored by electrochemical impedance spectroscopy (EIS). The growth kinetics of the anodic coating has been studied, and optimal conditions for the formation of a regularly porous oxide coating 10 – 12 μm thick with a regular pore diameter of 15 ± 5 nm on the alloy surface were determined. It is shown that subsequent electrochemical coloring for 15 min makes it possible to obtain a black color of the coatings due to the deposition of Cu and/or CuO nanoparticles into the pores. Simulation of electrical equivalent circuits makes it possible to separate and calculate the electrical parameters corresponding to different layers and elucidate their regular changes after coloring and hydrothermal treatment. The high corrosion resistance of electrochemically colored anodized alloy samples subjected to hydrothermal treatment has been revealed. The results obtained can be used in the application of protective and decorative anodic coatings for the manufacture, for example, of solar panels due to the high absorption and low reflectivity of black coatings.
{"title":"Study of black protective-decorative nanocomposite anodic coatings on the surface of AMg5 aluminum alloy","authors":"N. Yakovleva, A. N. Kokatev, K. I. Oskin, K. Stepanova, A. Shulga","doi":"10.26896/1028-6861-2023-89-7-34-44","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-34-44","url":null,"abstract":"A widely used nanocomposite coating is a porous anodic alumina colored by particles of metals or their compounds deposited into the pores. The insertion of light-scattering nanosized particles into the pores changes the optical properties of the anodic oxide, whereas the immobilization of metal nanoparticles in pores ensures their corrosion resistance. We present the results of studying black protective and decorative coatings on the surface of AMg5 aluminum alloy. The surface morphology of the samples was analyzed using atomic force microscopy, and the electrophysical properties were monitored by electrochemical impedance spectroscopy (EIS). The growth kinetics of the anodic coating has been studied, and optimal conditions for the formation of a regularly porous oxide coating 10 – 12 μm thick with a regular pore diameter of 15 ± 5 nm on the alloy surface were determined. It is shown that subsequent electrochemical coloring for 15 min makes it possible to obtain a black color of the coatings due to the deposition of Cu and/or CuO nanoparticles into the pores. Simulation of electrical equivalent circuits makes it possible to separate and calculate the electrical parameters corresponding to different layers and elucidate their regular changes after coloring and hydrothermal treatment. The high corrosion resistance of electrochemically colored anodized alloy samples subjected to hydrothermal treatment has been revealed. The results obtained can be used in the application of protective and decorative anodic coatings for the manufacture, for example, of solar panels due to the high absorption and low reflectivity of black coatings.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85660441","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}
Pub Date : 2023-07-26DOI: 10.26896/1028-6861-2023-89-7-45-50
V. Y. Goltsev, A. Osintsev, A. Plotnikov, V. I. Polskij
The possibility of evaluating the tear resistance of brittle materials by diametral compression test of short cylinders (solid and central with a central hole) has been analyzed. The computational analysis was performed by the finite element method using the ANSYS program. It is shown that the stress distribution in a disk with a hole is similar that without a hole but contains disturbances introduced by a stress concentrator in the form of a hole. The normalized values of the maximum first principal stresses for a disk with a hole exceed the values for a disk without a hole by more than 5 times. The experimental analysis was carried out by testing short cylinders, both solid and with a central hole, made of brittle materials: cast iron and graphite. It is noted that the fracture resistance, determined by the formula recommended by the ASTM D3967 – 95a standard, practically does not differ for solid cast iron samples, and for graphite differs by 1.5 times from the true tear resistance of materials; when testing samples with a central hole, the tear resistance differs from the standard values by a factor of 1.5 and almost 2.5, respectively. The different nature of the sample destruction is also noted: slow controlled rupture of cast iron and dynamic destruction of graphite with the corresponding deformation diagrams. The results of testing fuel pellets of uranium dioxide are given as an example of testing real cylindrical samples with a central hole. It is shown that the test results of ARV-1 graphite samples are in good agreement with the test results of fuel samples. Thus, the possibility of testing small-sized short cylinders according to the diametral compression scheme for indirect assessment of the tensile strength of brittle materials has been confirmed. A calculation formula is proposed for an indirect assessment of the tensile strength of brittle materials based on the results of testing small-sized short cylinders, both with and without a central hole according to the diametral compression scheme.
{"title":"Diametral compression of short cylinders with a central hole as a method for assessing the tear resistance of brittle materials","authors":"V. Y. Goltsev, A. Osintsev, A. Plotnikov, V. I. Polskij","doi":"10.26896/1028-6861-2023-89-7-45-50","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-45-50","url":null,"abstract":"The possibility of evaluating the tear resistance of brittle materials by diametral compression test of short cylinders (solid and central with a central hole) has been analyzed. The computational analysis was performed by the finite element method using the ANSYS program. It is shown that the stress distribution in a disk with a hole is similar that without a hole but contains disturbances introduced by a stress concentrator in the form of a hole. The normalized values of the maximum first principal stresses for a disk with a hole exceed the values for a disk without a hole by more than 5 times. The experimental analysis was carried out by testing short cylinders, both solid and with a central hole, made of brittle materials: cast iron and graphite. It is noted that the fracture resistance, determined by the formula recommended by the ASTM D3967 – 95a standard, practically does not differ for solid cast iron samples, and for graphite differs by 1.5 times from the true tear resistance of materials; when testing samples with a central hole, the tear resistance differs from the standard values by a factor of 1.5 and almost 2.5, respectively. The different nature of the sample destruction is also noted: slow controlled rupture of cast iron and dynamic destruction of graphite with the corresponding deformation diagrams. The results of testing fuel pellets of uranium dioxide are given as an example of testing real cylindrical samples with a central hole. It is shown that the test results of ARV-1 graphite samples are in good agreement with the test results of fuel samples. Thus, the possibility of testing small-sized short cylinders according to the diametral compression scheme for indirect assessment of the tensile strength of brittle materials has been confirmed. A calculation formula is proposed for an indirect assessment of the tensile strength of brittle materials based on the results of testing small-sized short cylinders, both with and without a central hole according to the diametral compression scheme.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81571107","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}
Pub Date : 2023-07-25DOI: 10.26896/1028-6861-2023-89-7-14-20
E. B. Kovaleva, S. G. Dyachkova, A. Ganina, I. Kuzora, V. A. Sergeev
The octane number for gaseous components (GC) is currently determined using the calculation method proceeding from the hydrocarbon composition. The method provides determination of the research octane number (RON) only. A discrepancy between the actual and predicted values of the octane number thus determined leads to an overestimated introduction of these components into the fuel which results in the reduced fuel performance and economic indicators of the production. In this regard, the development of a new approach to the determination of the blending octane number of low-boiling components is extremely important for designing optimal formulations of motor fuels. A method for determining the blending octane numbers (both RON and MON) of motor gasoline gaseous components has been improved due to preliminary sample preparation by bubbling which provided taking into account the proportion of involving fractions of C4 hydrocarbon and pentane-amylene along with the chemical nature of the base fuel components. It is shown that the value of the blending octane number for gaseous components depends on the hydrocarbon composition of the base component. Application of the developed method to determining the blending octane number of gaseous components of motor fuels allowed us to obtain optimal formulations of gasoline with the involvement of low-boiling by-products and increased the accuracy of forecasting the composition of fuels thus improving the economic performance of the production.
{"title":"A new approach to determining the blending octane number of gaseous components of motor gasolines","authors":"E. B. Kovaleva, S. G. Dyachkova, A. Ganina, I. Kuzora, V. A. Sergeev","doi":"10.26896/1028-6861-2023-89-7-14-20","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-14-20","url":null,"abstract":"The octane number for gaseous components (GC) is currently determined using the calculation method proceeding from the hydrocarbon composition. The method provides determination of the research octane number (RON) only. A discrepancy between the actual and predicted values of the octane number thus determined leads to an overestimated introduction of these components into the fuel which results in the reduced fuel performance and economic indicators of the production. In this regard, the development of a new approach to the determination of the blending octane number of low-boiling components is extremely important for designing optimal formulations of motor fuels. A method for determining the blending octane numbers (both RON and MON) of motor gasoline gaseous components has been improved due to preliminary sample preparation by bubbling which provided taking into account the proportion of involving fractions of C4 hydrocarbon and pentane-amylene along with the chemical nature of the base fuel components. It is shown that the value of the blending octane number for gaseous components depends on the hydrocarbon composition of the base component. Application of the developed method to determining the blending octane number of gaseous components of motor fuels allowed us to obtain optimal formulations of gasoline with the involvement of low-boiling by-products and increased the accuracy of forecasting the composition of fuels thus improving the economic performance of the production.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89947225","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}
Pub Date : 2023-07-25DOI: 10.26896/1028-6861-2023-89-7-21-24
J. Jamur
In medical practice, nonsteroidal anti-inflammatory drugs (NSAIDs) are often used to treat osteoarthritis and rheumatoid arthritis. Ibuprofen is a well-known NSAID, analgesic, and antipyretic medication. This chemical is an active ingredient of several oral medications that are offered in tablet, gel pellet, and syrup forms and has higher efficacy, tolerance, and side effect rates than other compounds, including pyrazolone derivatives. We present a unique plasma-assisted desorption/ionization mass spectrometry (PADI-MS) approach for improving pharmaceutically important solids using an ibuprofen tablet as a model solid sample. The goal of the study is to create an innovative mass spectrometric method that could be used for quick and accurate analysis in the development of pharmaceutically relevant compounds. Sniffer tubes were used to route sample ions into a single quadrupole MS, with each acquisition lasting for 1 minute. Without any prior preparation, samples of ibuprofen tablets were directly exposed to PADI plasma for one minute at an atmosphere pressure. The approach is rapid, easy to use, and needs little to no sample preparation. In this study, the settings were improved by optimization of several parameters, such as plasma power, plasma-to-sample distance, and inner/outer flows of helium carrier gas, which were found to be 8 W, 2 mm, and 284 mL/min, respectively. The PADI-MS method provides a real-time information about structural features on the compounds. Ibuprofen tablets were used as a paradigm for pharmaceutically significant materials and direct PADI-MS analysis without a preliminary sample -treatment appeared to be successful: according to PADI-MS data a medication can be examined after one minute of plasma exposure.
{"title":"Optimization of Plasma-Assisted Desorption/Ionization-Mass Spectrometry for Analysis of Ibuprofen","authors":"J. Jamur","doi":"10.26896/1028-6861-2023-89-7-21-24","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-21-24","url":null,"abstract":"In medical practice, nonsteroidal anti-inflammatory drugs (NSAIDs) are often used to treat osteoarthritis and rheumatoid arthritis. Ibuprofen is a well-known NSAID, analgesic, and antipyretic medication. This chemical is an active ingredient of several oral medications that are offered in tablet, gel pellet, and syrup forms and has higher efficacy, tolerance, and side effect rates than other compounds, including pyrazolone derivatives. We present a unique plasma-assisted desorption/ionization mass spectrometry (PADI-MS) approach for improving pharmaceutically important solids using an ibuprofen tablet as a model solid sample. The goal of the study is to create an innovative mass spectrometric method that could be used for quick and accurate analysis in the development of pharmaceutically relevant compounds. Sniffer tubes were used to route sample ions into a single quadrupole MS, with each acquisition lasting for 1 minute. Without any prior preparation, samples of ibuprofen tablets were directly exposed to PADI plasma for one minute at an atmosphere pressure. The approach is rapid, easy to use, and needs little to no sample preparation. In this study, the settings were improved by optimization of several parameters, such as plasma power, plasma-to-sample distance, and inner/outer flows of helium carrier gas, which were found to be 8 W, 2 mm, and 284 mL/min, respectively. The PADI-MS method provides a real-time information about structural features on the compounds. Ibuprofen tablets were used as a paradigm for pharmaceutically significant materials and direct PADI-MS analysis without a preliminary sample -treatment appeared to be successful: according to PADI-MS data a medication can be examined after one minute of plasma exposure.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82312578","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}
Pub Date : 2023-07-25DOI: 10.26896/1028-6861-2023-89-7-8-13
I. Platonov, V. Platonov, A. I. Balashova, I. N. Kolesnichenko, I. M. Mukhanova, N. A. Aphonin
Miniaturization coupled with the introduction of microfluidic systems and devices into the chromatograph hardware is one of the main approaches to the creation of modern gas chromatographic equipment. For variable sample dosing in automatic mode, a microfluidic dosing valve based on microelectromechanical systems was developed. The manufactured device provides multi-point calibration with a single calibration gas mixture. Two methods for constructing a calibration dependence were implemented using the developed dosing device: a calibrated loop for 250 μl taken as a constant dosing loop and calibration solutions (gas mixtures of propane in helium (GSO 10463–2014) with concentrations of 0.0025, 0.025, 0.25, 0.5б and 1.25 % vol.) were used in the first method, whereas in the second one a variable dosing provided by the developed microfluidic dosing valve which consisted in the possibility of introducing a different amount of the calibration gas mixture of propane in helium (2.5 % vol.) into the chromatographic column due to changing the time of sample injection at a constant pressure was implemented. The experiment was carried out on a PIA gas microchromatograph with a MEMS column (a sectional plane of 1 × 1 mm and a 1-m channel) with a Carbopak B adsorbent. It is shown that the use of the developed dosing device as part of the PIA gas microchromatograph makes it possible to carry out a metrologically assured quantitative analysis.
{"title":"Variable microfluidic dosing valve for gas chromatography","authors":"I. Platonov, V. Platonov, A. I. Balashova, I. N. Kolesnichenko, I. M. Mukhanova, N. A. Aphonin","doi":"10.26896/1028-6861-2023-89-7-8-13","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-8-13","url":null,"abstract":"Miniaturization coupled with the introduction of microfluidic systems and devices into the chromatograph hardware is one of the main approaches to the creation of modern gas chromatographic equipment. For variable sample dosing in automatic mode, a microfluidic dosing valve based on microelectromechanical systems was developed. The manufactured device provides multi-point calibration with a single calibration gas mixture. Two methods for constructing a calibration dependence were implemented using the developed dosing device: a calibrated loop for 250 μl taken as a constant dosing loop and calibration solutions (gas mixtures of propane in helium (GSO 10463–2014) with concentrations of 0.0025, 0.025, 0.25, 0.5б and 1.25 % vol.) were used in the first method, whereas in the second one a variable dosing provided by the developed microfluidic dosing valve which consisted in the possibility of introducing a different amount of the calibration gas mixture of propane in helium (2.5 % vol.) into the chromatographic column due to changing the time of sample injection at a constant pressure was implemented. The experiment was carried out on a PIA gas microchromatograph with a MEMS column (a sectional plane of 1 × 1 mm and a 1-m channel) with a Carbopak B adsorbent. It is shown that the use of the developed dosing device as part of the PIA gas microchromatograph makes it possible to carry out a metrologically assured quantitative analysis.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73436918","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}
Pub Date : 2023-07-25DOI: 10.26896/1028-6861-2023-89-7-25-33
I. Schemerov, A. Polyakov, P. B. Lagov, S. Kobeleva, A. Kochkova, Yury O Kulanchikov, A. Doroshkevich, V. Kirilov
The reverse current recovery time is an important parameter of diodes, fast rectifiers and transistors which determined their high-frequency properties and area of application. Defects in the structure may sufficiency reduce the cutoff frequency and lead to overheating. The reverse recovery of the low currents in the α- and β-Ga2O3 Schottky diodes was measured and analyzed in this study. The reverse recovery time in the β-Ga2O3-based Schottky diode is limited mainly by the relaxation of the RC-circuit formed by the equivalent diode circuit and can be very low (20 nsec in this case). Irradiation can introduce some defects in the structure, which may act as deep levels and prolong the relaxation. We have demonstrated experimentally that increasing serial resistance of the circuit lead to an increase in the reverse recovery time. But we can point an additional part of relaxation that can be attributed to the emission from deep levels in the forbidden gap of the semiconductor. It is shown that prolongation increases with the reverse recovery time but saturates. In the α-Ga2O3-based structures the reverse recovery time measured after proton irradiation was 6 μsec, twice as high than it can be expected from RC-circuit relaxation time. These deep levels can be associated with interstitial oxygen atoms. The results obtained can be used to improve the technology of crystal growth to produce Schottky diodes with a high boundary frequency.
{"title":"The effect of trapping sites introduced by 1 MeV proton irradiation on the reverse current recovery time in Ga2O3-based Schottky diodes","authors":"I. Schemerov, A. Polyakov, P. B. Lagov, S. Kobeleva, A. Kochkova, Yury O Kulanchikov, A. Doroshkevich, V. Kirilov","doi":"10.26896/1028-6861-2023-89-7-25-33","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-7-25-33","url":null,"abstract":"The reverse current recovery time is an important parameter of diodes, fast rectifiers and transistors which determined their high-frequency properties and area of application. Defects in the structure may sufficiency reduce the cutoff frequency and lead to overheating. The reverse recovery of the low currents in the α- and β-Ga2O3 Schottky diodes was measured and analyzed in this study. The reverse recovery time in the β-Ga2O3-based Schottky diode is limited mainly by the relaxation of the RC-circuit formed by the equivalent diode circuit and can be very low (20 nsec in this case). Irradiation can introduce some defects in the structure, which may act as deep levels and prolong the relaxation. We have demonstrated experimentally that increasing serial resistance of the circuit lead to an increase in the reverse recovery time. But we can point an additional part of relaxation that can be attributed to the emission from deep levels in the forbidden gap of the semiconductor. It is shown that prolongation increases with the reverse recovery time but saturates. In the α-Ga2O3-based structures the reverse recovery time measured after proton irradiation was 6 μsec, twice as high than it can be expected from RC-circuit relaxation time. These deep levels can be associated with interstitial oxygen atoms. The results obtained can be used to improve the technology of crystal growth to produce Schottky diodes with a high boundary frequency.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73302568","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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