База данных: Статьи
Страница 7, Результатов: 89
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61.
Подробнее
35
B15
Bagova, Z.
Analysis and prospective utilization of technogenic slag waste from a lead plant. [Текст] / Z. Bagova, K. Zhantasov, G. Turebekova, B. Sapargaliyeva, Javier Rodrigo-Iiarri // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 22-28
ББК 35
Рубрики: chemical Technology
Кл.слова (ненормированные):
waste -- lead-zinc waste -- secondary raw materials -- non-ferrous metals -- valuable components -- waste processing -- waste disposal -- low-waste and non-waste technologies
Аннотация: The article presents the analysis and results of the study of technogenic slag waste of lead-zinc production. Slags of lead-zinc production contain a large number of toxic compounds: lead, zinc, osmium, cadmium, which are dangerous sources of environmental pollution. Due to the open storage of slags, it was found that the maximum permissible concentrations of lead were exceeded. Utilization of man-made slag waste is of great importance for reducing the negative impact on the safety of life and improving the environmental situation in the region. At the same time, slags are valuable raw materials containing compounds of non-ferrous and rare-earth metals.
Держатели документа:
WKU
Доп.точки доступа:
Zhantasov, K.
Turebekova, G.
Sapargaliyeva, B.
Rodrigo-Iiarri, Javier
B15
Bagova, Z.
Analysis and prospective utilization of technogenic slag waste from a lead plant. [Текст] / Z. Bagova, K. Zhantasov, G. Turebekova, B. Sapargaliyeva, Javier Rodrigo-Iiarri // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 22-28
Рубрики: chemical Technology
Кл.слова (ненормированные):
waste -- lead-zinc waste -- secondary raw materials -- non-ferrous metals -- valuable components -- waste processing -- waste disposal -- low-waste and non-waste technologies
Аннотация: The article presents the analysis and results of the study of technogenic slag waste of lead-zinc production. Slags of lead-zinc production contain a large number of toxic compounds: lead, zinc, osmium, cadmium, which are dangerous sources of environmental pollution. Due to the open storage of slags, it was found that the maximum permissible concentrations of lead were exceeded. Utilization of man-made slag waste is of great importance for reducing the negative impact on the safety of life and improving the environmental situation in the region. At the same time, slags are valuable raw materials containing compounds of non-ferrous and rare-earth metals.
Держатели документа:
WKU
Доп.точки доступа:
Zhantasov, K.
Turebekova, G.
Sapargaliyeva, B.
Rodrigo-Iiarri, Javier
62.
Подробнее
35
Y45
Yermagambet, B. T.
Production of carbon nanofibers based on coal tar and polyacryonitrile by electrospinning method. [Текст] / B. T. Yermagambet, M. K. Kazankapova, A. T. Nauryzbayeva, Zh. M. Kassenova // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 72-80
ББК 35
Рубрики: chemical Technology
Кл.слова (ненормированные):
carbon nanofiber -- coal tar -- polyacrylonitrile -- electrospinning -- oxidation -- carbonization
Аннотация: The article presents experiments on obtaining composite fibers based on Shubarkol coal tar (CT) and polycarlonitrile (PAN) by electrospinning in a laboratory setup. As a result of energy dispersive X-ray spectroscopy and SEM microscopy, the elemental composition (C-85.83%) and the diameter of the carbon fiber were determined, which ranged from 89.0 nm to 449.8 nm. The resulting CNF was subjected to oxidation in air at 300 °C, the holding time was 1 hour, after which the carbonization process was carried out at 800 °C, followed by cooling to room temperature.
Держатели документа:
WKU
Доп.точки доступа:
Kazankapova, M.K.
Nauryzbayeva, A.T.
Kassenova, Zh.M.
Y45
Yermagambet, B. T.
Production of carbon nanofibers based on coal tar and polyacryonitrile by electrospinning method. [Текст] / B. T. Yermagambet, M. K. Kazankapova, A. T. Nauryzbayeva, Zh. M. Kassenova // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 72-80
Рубрики: chemical Technology
Кл.слова (ненормированные):
carbon nanofiber -- coal tar -- polyacrylonitrile -- electrospinning -- oxidation -- carbonization
Аннотация: The article presents experiments on obtaining composite fibers based on Shubarkol coal tar (CT) and polycarlonitrile (PAN) by electrospinning in a laboratory setup. As a result of energy dispersive X-ray spectroscopy and SEM microscopy, the elemental composition (C-85.83%) and the diameter of the carbon fiber were determined, which ranged from 89.0 nm to 449.8 nm. The resulting CNF was subjected to oxidation in air at 300 °C, the holding time was 1 hour, after which the carbonization process was carried out at 800 °C, followed by cooling to room temperature.
Держатели документа:
WKU
Доп.точки доступа:
Kazankapova, M.K.
Nauryzbayeva, A.T.
Kassenova, Zh.M.
63.
Подробнее
38.3
S70
Sokolova, Ya. А.
The study of the properties and structure of cement binding composition on electrolyte acqueous solutions activated by mechanomagnetic method. [Текст] / Ya. А. Sokolova, M. V. Akulova, B. R. Isakulov, А. G. Sokolova [et al.] // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 86-91
ББК 38.3
Рубрики: Строительные материалы
Кл.слова (ненормированные):
Cement compositions, -- mechanomagnetic activation -- electrolyte aqueous solutions -- differential thermo gravimetric analysis -- compressive strength -- structure formation of binders -- sodium thiosulphate -- calcium chloride
Аннотация: In the present paper, the issues of studying the influence of complex activation of grouting fluid on the structure and properties of the hardened cement paste and concrete are considered. The problem is relevant for manufacturing of building materials. In the paper, there was used the method of applying in the concrete mix composition of the elementary chemical substances undergone special physical treatment by means of mechanomagnetic activation. For more profound study of the structure formation processes in the hardened cement paste, the method of differential thermo gravimetric analysis has been used. As the research results have shown, the concrete samples on the activated electrolyte solutions are characterized by improved strength. In addition, on the base of differential thermo gravimetric analysis, it was proven that in the studied samples of the hardened cement paste on the electrolyte solutions activated by the method of mechanomagnetic treatment, the less calcium hydroxide and the more hydrated calcium silicate with amorphous and fine crystalline is formed. The obtained results for cement composites could be applied when manufacturing effective binder for concretes and mortars in the production of building materials and structures.
Держатели документа:
WKU
Доп.точки доступа:
Akulova, M.V.
Isakulov, B.R.
Sokolova, А.G.
Kul’sharov, B.B.
Isakulov, А.B.
S70
Sokolova, Ya. А.
The study of the properties and structure of cement binding composition on electrolyte acqueous solutions activated by mechanomagnetic method. [Текст] / Ya. А. Sokolova, M. V. Akulova, B. R. Isakulov, А. G. Sokolova [et al.] // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 86-91
Рубрики: Строительные материалы
Кл.слова (ненормированные):
Cement compositions, -- mechanomagnetic activation -- electrolyte aqueous solutions -- differential thermo gravimetric analysis -- compressive strength -- structure formation of binders -- sodium thiosulphate -- calcium chloride
Аннотация: In the present paper, the issues of studying the influence of complex activation of grouting fluid on the structure and properties of the hardened cement paste and concrete are considered. The problem is relevant for manufacturing of building materials. In the paper, there was used the method of applying in the concrete mix composition of the elementary chemical substances undergone special physical treatment by means of mechanomagnetic activation. For more profound study of the structure formation processes in the hardened cement paste, the method of differential thermo gravimetric analysis has been used. As the research results have shown, the concrete samples on the activated electrolyte solutions are characterized by improved strength. In addition, on the base of differential thermo gravimetric analysis, it was proven that in the studied samples of the hardened cement paste on the electrolyte solutions activated by the method of mechanomagnetic treatment, the less calcium hydroxide and the more hydrated calcium silicate with amorphous and fine crystalline is formed. The obtained results for cement composites could be applied when manufacturing effective binder for concretes and mortars in the production of building materials and structures.
Держатели документа:
WKU
Доп.точки доступа:
Akulova, M.V.
Isakulov, B.R.
Sokolova, А.G.
Kul’sharov, B.B.
Isakulov, А.B.
64.
Подробнее
26.3
S14
Safarov, R. Z.
Elemental analysis of local and foreign raw materials for the production of trimanganese tetraoxide pigment. [Текст] / R. Z. Safarov, A. Zhandildenova, D. B. Kargin, B. B. Makhmutov [и др.] // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 92-98
ББК 26.3
Рубрики: geology
Кл.слова (ненормированные):
hausmannite -- pigment -- manganese ore -- nanopowders -- electronic microscopy -- energy-dispersive analysis
Аннотация: In the course of continuation of scientific research in the development of Kazakhstani technology for the production of trimanganese tetraoxide pigment, there have been proposed new methods of analysis which make it possible to investigate new nanostructural materials sourced from local deposits. The results obtained are of practical importance and serve as the foundation for developing new technologically advanced domestic production of a competitive product that is in demand both on the national and international markets. The available methods are not able to highlight the particularity and diversity of Kazakhstani manganese ores due to the uneven distribution of manganese minerals and host (waste) rock, the quantitative ratio of rock-forming components and their variation instability. Methods of energy-dispersive analysis of manganese ores from Kazakhstani Zhaksylyk and Bogach deposits have been put forward, electronic micrographs, spectrograms of samples, diagrams of normalized distribution of elements on the surface of samples have been obtained and a comparative analysis with raw analogue samples of some foreign manufacturers has been performed.
Держатели документа:
WKU
Доп.точки доступа:
Zhandildenova, A.
Kargin, D. B.
Makhmutov, B. B.
Kamatov, R. M.
Shomanova, Zh. K.
S14
Safarov, R. Z.
Elemental analysis of local and foreign raw materials for the production of trimanganese tetraoxide pigment. [Текст] / R. Z. Safarov, A. Zhandildenova, D. B. Kargin, B. B. Makhmutov [и др.] // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 92-98
Рубрики: geology
Кл.слова (ненормированные):
hausmannite -- pigment -- manganese ore -- nanopowders -- electronic microscopy -- energy-dispersive analysis
Аннотация: In the course of continuation of scientific research in the development of Kazakhstani technology for the production of trimanganese tetraoxide pigment, there have been proposed new methods of analysis which make it possible to investigate new nanostructural materials sourced from local deposits. The results obtained are of practical importance and serve as the foundation for developing new technologically advanced domestic production of a competitive product that is in demand both on the national and international markets. The available methods are not able to highlight the particularity and diversity of Kazakhstani manganese ores due to the uneven distribution of manganese minerals and host (waste) rock, the quantitative ratio of rock-forming components and their variation instability. Methods of energy-dispersive analysis of manganese ores from Kazakhstani Zhaksylyk and Bogach deposits have been put forward, electronic micrographs, spectrograms of samples, diagrams of normalized distribution of elements on the surface of samples have been obtained and a comparative analysis with raw analogue samples of some foreign manufacturers has been performed.
Держатели документа:
WKU
Доп.точки доступа:
Zhandildenova, A.
Kargin, D. B.
Makhmutov, B. B.
Kamatov, R. M.
Shomanova, Zh. K.
65.
Подробнее
24
I-54
Ilyassov, A. E.
Investigation of the sorption characteristics of activated carbons. [Текст] / A. E. Ilyassov, A.О. Baikonurova, B. N. Surimbayev // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 105-109
ББК 24
Рубрики: chemistry
Кл.слова (ненормированные):
activated carbon -- sorption -- sorption capacity of coal -- sorbent -- gold
Аннотация: The article presents the results of a comparison of the sorption characteristics for gold of crushed activated carbon of the foreign Haycarb brand, obtained from expensive raw materials - coconut shells, and crushed activated carbon of the domestic Shubarkol brand, obtained from relatively cheap raw materials - low-ash coking coal. The activated carbon Shubarkol crushed to a class of -3.6+1.0 mm, was produced in Kazakhstan from coking coal by Shubarkolkomir JSC.
Держатели документа:
WKU
Доп.точки доступа:
Baikonurova, A.О.
Surimbayev, B.N.
I-54
Ilyassov, A. E.
Investigation of the sorption characteristics of activated carbons. [Текст] / A. E. Ilyassov, A.О. Baikonurova, B. N. Surimbayev // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 105-109
Рубрики: chemistry
Кл.слова (ненормированные):
activated carbon -- sorption -- sorption capacity of coal -- sorbent -- gold
Аннотация: The article presents the results of a comparison of the sorption characteristics for gold of crushed activated carbon of the foreign Haycarb brand, obtained from expensive raw materials - coconut shells, and crushed activated carbon of the domestic Shubarkol brand, obtained from relatively cheap raw materials - low-ash coking coal. The activated carbon Shubarkol crushed to a class of -3.6+1.0 mm, was produced in Kazakhstan from coking coal by Shubarkolkomir JSC.
Держатели документа:
WKU
Доп.точки доступа:
Baikonurova, A.О.
Surimbayev, B.N.
66.
Подробнее
36
T91
Tuleshova, Z.
Investigation of the composition of polyphenolic substances of the juice from artichoke tubers. [Текст] / Z. Tuleshova, G. I. Baigazieva, E. Askarbekov // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 142-148
ББК 36
Рубрики: Пищевые производства
Кл.слова (ненормированные):
jerusalem artichoke -- chemical composition -- nutritional value -- polyphenolic substances
Аннотация: In this article, the chemical composition of tubers and juice-semi-finished products from jerusalem artichoke is investigated. The results of the studies showed that the bulk of the dry substances in jerusalem artichoke tubers are carbohydrates, most of which are represented by fructosides. In the semi-finished juice passes: oligosaccharides 22.54 %, monosaccharides 1.61%, as well as part of the structural polysaccharides-fiber 0.07 %, pectin substances 1.84 %.
Держатели документа:
WKU
Доп.точки доступа:
Baigazieva, G.I.
Askarbekov, E.
T91
Tuleshova, Z.
Investigation of the composition of polyphenolic substances of the juice from artichoke tubers. [Текст] / Z. Tuleshova, G. I. Baigazieva, E. Askarbekov // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №2. - P. 142-148
Рубрики: Пищевые производства
Кл.слова (ненормированные):
jerusalem artichoke -- chemical composition -- nutritional value -- polyphenolic substances
Аннотация: In this article, the chemical composition of tubers and juice-semi-finished products from jerusalem artichoke is investigated. The results of the studies showed that the bulk of the dry substances in jerusalem artichoke tubers are carbohydrates, most of which are represented by fructosides. In the semi-finished juice passes: oligosaccharides 22.54 %, monosaccharides 1.61%, as well as part of the structural polysaccharides-fiber 0.07 %, pectin substances 1.84 %.
Держатели документа:
WKU
Доп.точки доступа:
Baigazieva, G.I.
Askarbekov, E.
67.
Подробнее
35
J21
Jalmakhanbetova, R.I.
Calculate the standard enthalpies of combustion , formation and melting of the complex roseofungin with a-, B- and y- cyclodextrin. [Текст] / R.I. Jalmakhanbetova, Ye. M. Suleimen, B. K. Kasenov // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 44-47
ББК 35
Рубрики: chemical Technology
Кл.слова (ненормированные):
roseofungin -- cyclodextrin -- standard enthalpy of combustion -- standard enthalpy of formation -- enthalpy of melting of a complex
Аннотация: One of the most important quantities in chemical thermodynamics and thermochemistry is the enthalpy of combustion. Of the currently existing methods for calculating the heat of combustion of natural and synthetic organic compounds, the most acceptable and correct in our case was the Karash method. In this study, the standard enthalpy of combustion, the standard enthalpy of formation, and the melting enthalpy of the antibiotic roseofungin and its cyclodextrin derivatives were calculated. As a result of the study, the thermodynamic constants of the standard enthalpies of combustion, standard enthalpies of formation, and the enthalpies of melting of the above compounds were calculated, which are of interest for physicochemical modeling of processes with their participation, serve as initial information arrays for loading into fundamental thermodynamic data banks and reference books, and is also important for standardization and certification of these complexes. It should be noted that the presence of a large number of hydroxyl groups in the structures of the studied complexes allows them to be attributed to polar compounds.
Держатели документа:
WKU
Доп.точки доступа:
Suleimen, Ye.M.
Kasenov, B.K.
J21
Jalmakhanbetova, R.I.
Calculate the standard enthalpies of combustion , formation and melting of the complex roseofungin with a-, B- and y- cyclodextrin. [Текст] / R.I. Jalmakhanbetova, Ye. M. Suleimen, B. K. Kasenov // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 44-47
Рубрики: chemical Technology
Кл.слова (ненормированные):
roseofungin -- cyclodextrin -- standard enthalpy of combustion -- standard enthalpy of formation -- enthalpy of melting of a complex
Аннотация: One of the most important quantities in chemical thermodynamics and thermochemistry is the enthalpy of combustion. Of the currently existing methods for calculating the heat of combustion of natural and synthetic organic compounds, the most acceptable and correct in our case was the Karash method. In this study, the standard enthalpy of combustion, the standard enthalpy of formation, and the melting enthalpy of the antibiotic roseofungin and its cyclodextrin derivatives were calculated. As a result of the study, the thermodynamic constants of the standard enthalpies of combustion, standard enthalpies of formation, and the enthalpies of melting of the above compounds were calculated, which are of interest for physicochemical modeling of processes with their participation, serve as initial information arrays for loading into fundamental thermodynamic data banks and reference books, and is also important for standardization and certification of these complexes. It should be noted that the presence of a large number of hydroxyl groups in the structures of the studied complexes allows them to be attributed to polar compounds.
Держатели документа:
WKU
Доп.точки доступа:
Suleimen, Ye.M.
Kasenov, B.K.
68.
Подробнее
24
K17
Кairbekov, Zh. К.
Physicochemical and antioxidant properties of humic acids of low-mineralized peloids of the Tuzkol deposit. [Текст] / Zh. К. Кairbekov, I. M. Jeldybayeva, D. Z. Аbilmazhinova, S. M. Suimbayeva // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 48-53
ББК 24
Рубрики: chemistry
Кл.слова (ненормированные):
Low-mineralized sludge sulphide mud (peloids) -- humic -- fulvic -- hymatomelanic -- humic acids -- antioxidant activity
Аннотация: As a result of studies it was found that the peloids of the deposit of Tuzkol Lake (Republic of Kazakhstan) are high quality medium-sulfide, weakly alkaline sludge muds. It was found that peloid-derived humic acid contains 49.63 % oxygen, 22.37% carbon, 9.65 % silicon and 6.26% calcium; it also contains Na, Mg, Al, Fe and an insignificant amount of S, Cl, K, F. Electron microscopy and IR spectroscopy analysis of the molecular structure of humic substances of peloids indicated that their macromolecule consists of framework olefinic and aromatic fragments with a substantial proportion of unoxidized aliphatic groups, as well as aromatic structures containing carboxyl groups. The findings of amperometric detection of the antioxidant properties of humic acids suggest that they have antioxidant activity, which will make it possible to use them as a biologically active substance for medicines.
Держатели документа:
WKU
Доп.точки доступа:
Jeldybayeva, I.M.
Аbilmazhinova, D.Z.
Suimbayeva, S.M.
K17
Кairbekov, Zh. К.
Physicochemical and antioxidant properties of humic acids of low-mineralized peloids of the Tuzkol deposit. [Текст] / Zh. К. Кairbekov, I. M. Jeldybayeva, D. Z. Аbilmazhinova, S. M. Suimbayeva // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 48-53
Рубрики: chemistry
Кл.слова (ненормированные):
Low-mineralized sludge sulphide mud (peloids) -- humic -- fulvic -- hymatomelanic -- humic acids -- antioxidant activity
Аннотация: As a result of studies it was found that the peloids of the deposit of Tuzkol Lake (Republic of Kazakhstan) are high quality medium-sulfide, weakly alkaline sludge muds. It was found that peloid-derived humic acid contains 49.63 % oxygen, 22.37% carbon, 9.65 % silicon and 6.26% calcium; it also contains Na, Mg, Al, Fe and an insignificant amount of S, Cl, K, F. Electron microscopy and IR spectroscopy analysis of the molecular structure of humic substances of peloids indicated that their macromolecule consists of framework olefinic and aromatic fragments with a substantial proportion of unoxidized aliphatic groups, as well as aromatic structures containing carboxyl groups. The findings of amperometric detection of the antioxidant properties of humic acids suggest that they have antioxidant activity, which will make it possible to use them as a biologically active substance for medicines.
Держатели документа:
WKU
Доп.точки доступа:
Jeldybayeva, I.M.
Аbilmazhinova, D.Z.
Suimbayeva, S.M.
69.
Подробнее
24
N94
Nurdillayeva, R. N.
Dissolution of stanless steel in sodium chloride solution at polarization by non-stationary current. [Текст] / R. N. Nurdillayeva // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 75-81
ББК 24
Рубрики: chemistry
Кл.слова (ненормированные):
stainless steel -- titanium electrode -- alternating current -- iron (II) ions -- chromium (III)ions -- current density -- and current efficiency
Аннотация: Stainless steel is in great demand due to its mechanical strength, heat resistance, and resistance to corrosive environments. This article presents the result of a study of the electrochemical dissolution behavior of a stainless steel electrode (12X18H10T) at polarization by 50 Hz alternating current in a neutral medium (NaCl). Preliminary experiments have shown that the main processes do not take place when two stainless steel electrodes are polarized with an alternating current. It was observed that by the polarization of the “stainless steel – titanium” pair electrodes with alternating current, the alloy is intensively dissolved with the formation of iron (II) and chromium (III) ions. This is due to the "valve" properties of the oxide layer formed on the surface of the titanium electrode. A change in the value of the current density of the titanium and steel electrodes significantly affects the process of electrochemical dissolution of the alloy. At high current densities, the dissolution rate of the alloy decreases due to the deterioration of the current correcting properties of titanium. With an increase in the electrolyte concentration, the current efficiency is reduced as salt passivation occurs. A maximum value of the current efficiency of dissolution of stainless steel was observed at a current frequency of 50 Hz. High frequencies of the alternating current do not provide an adjustable duration of the anodic half-cycle for the oxidation reaction due to the frequent change of half-cycles of the alternating current. It was observed that increasing the temperature of the electrolyte reduces the current efficiency of the electrochemical dissolution of stainless steel electrodes. The effects of main electrochemical parameters on the electrolysis process have been investigated, and the optimal conditions of the alloy dissolution were established (іТі = 60 kA/m2, іSS = 800 A/m2, [NaCl] = 2.0 M, t = 30, ν = 50 Hz.).
Держатели документа:
WKU
Доп.точки доступа:
Sauirbay, Zh.G.
Bayeshov, A.B.
N94
Nurdillayeva, R. N.
Dissolution of stanless steel in sodium chloride solution at polarization by non-stationary current. [Текст] / R. N. Nurdillayeva // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 75-81
Рубрики: chemistry
Кл.слова (ненормированные):
stainless steel -- titanium electrode -- alternating current -- iron (II) ions -- chromium (III)ions -- current density -- and current efficiency
Аннотация: Stainless steel is in great demand due to its mechanical strength, heat resistance, and resistance to corrosive environments. This article presents the result of a study of the electrochemical dissolution behavior of a stainless steel electrode (12X18H10T) at polarization by 50 Hz alternating current in a neutral medium (NaCl). Preliminary experiments have shown that the main processes do not take place when two stainless steel electrodes are polarized with an alternating current. It was observed that by the polarization of the “stainless steel – titanium” pair electrodes with alternating current, the alloy is intensively dissolved with the formation of iron (II) and chromium (III) ions. This is due to the "valve" properties of the oxide layer formed on the surface of the titanium electrode. A change in the value of the current density of the titanium and steel electrodes significantly affects the process of electrochemical dissolution of the alloy. At high current densities, the dissolution rate of the alloy decreases due to the deterioration of the current correcting properties of titanium. With an increase in the electrolyte concentration, the current efficiency is reduced as salt passivation occurs. A maximum value of the current efficiency of dissolution of stainless steel was observed at a current frequency of 50 Hz. High frequencies of the alternating current do not provide an adjustable duration of the anodic half-cycle for the oxidation reaction due to the frequent change of half-cycles of the alternating current. It was observed that increasing the temperature of the electrolyte reduces the current efficiency of the electrochemical dissolution of stainless steel electrodes. The effects of main electrochemical parameters on the electrolysis process have been investigated, and the optimal conditions of the alloy dissolution were established (іТі = 60 kA/m2, іSS = 800 A/m2, [NaCl] = 2.0 M, t = 30, ν = 50 Hz.).
Держатели документа:
WKU
Доп.точки доступа:
Sauirbay, Zh.G.
Bayeshov, A.B.
70.
Подробнее
35
R18
Rakhimberlinova, Zh. B.
Chemical activation of the surface of the burnt rock by various modifiers. [Текст] / Zh. B. Rakhimberlinova, I. V. Kulakov, A.Zh. Alimzhanova, M. М. Mussirepov, N. E. Nakypbekova // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 81-86
ББК 35
Рубрики: chemical Technology
Кл.слова (ненормированные):
oxidized coals -- humic acids -- inorganic surfaces -- burnt rock -- host rock -- modifiers
Аннотация: This article presents the results of experimental studies of the process of grafting humic acids and their functional derivatives on modified and unmodified surfaces of burnt rock. It is shown that the inoculation of humic acids on inorganic carriers is more successful with the preliminary activation of the surface of burnt rocks.
Держатели документа:
WKU
Доп.точки доступа:
Kulakov, I.V.
Alimzhanova, A.Zh.
Mussirepov, M.М.
Nakypbekova, N.E.
R18
Rakhimberlinova, Zh. B.
Chemical activation of the surface of the burnt rock by various modifiers. [Текст] / Zh. B. Rakhimberlinova, I. V. Kulakov, A.Zh. Alimzhanova, M. М. Mussirepov, N. E. Nakypbekova // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 81-86
Рубрики: chemical Technology
Кл.слова (ненормированные):
oxidized coals -- humic acids -- inorganic surfaces -- burnt rock -- host rock -- modifiers
Аннотация: This article presents the results of experimental studies of the process of grafting humic acids and their functional derivatives on modified and unmodified surfaces of burnt rock. It is shown that the inoculation of humic acids on inorganic carriers is more successful with the preliminary activation of the surface of burnt rocks.
Держатели документа:
WKU
Доп.точки доступа:
Kulakov, I.V.
Alimzhanova, A.Zh.
Mussirepov, M.М.
Nakypbekova, N.E.
Страница 7, Результатов: 89