Choice of metadata Статьи
Page 38, Results: 424
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371.
Подробнее
36
A53
Anarbekova, Z. А.
The influence of yeast races on the aroma-forming substances of table wines. [Текст] / Z. А. Anarbekova, G. I. Baigazieva // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 12-18
ББК 36
Рубрики: Пищевое производство
Кл.слова (ненормированные):
Wine yeast -- fermentation -- enzyme activity -- ermentation dynamics -- organic acids -- aroma-forming substances.
Аннотация: This article shows the influence of the yeast race on the fermentation dynamics of white grape must, the composition of organic acids and aroma-forming components. The races that ensure the production of high-quality wine materials are identified.
Держатели документа:
WKU
Доп.точки доступа:
Baigazieva, G.I.
A53
Anarbekova, Z. А.
The influence of yeast races on the aroma-forming substances of table wines. [Текст] / Z. А. Anarbekova, G. I. Baigazieva // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 12-18
Рубрики: Пищевое производство
Кл.слова (ненормированные):
Wine yeast -- fermentation -- enzyme activity -- ermentation dynamics -- organic acids -- aroma-forming substances.
Аннотация: This article shows the influence of the yeast race on the fermentation dynamics of white grape must, the composition of organic acids and aroma-forming components. The races that ensure the production of high-quality wine materials are identified.
Держатели документа:
WKU
Доп.точки доступа:
Baigazieva, G.I.
372.
Подробнее
35
A92
Augaliev, D. B.
Oxidative dimerization of methane to C2 hydrocarbons. [Текст] / D. B. Augaliev, M. K. Erkibaeva, A. O. Aidarova // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 18-24
ББК 35
Рубрики: chemical Technology
Кл.слова (ненормированные):
ODM reaction -- C2 hydrocarbons -- SHS method -- temperature of reaction
Аннотация: The purpose of this work is to study the reaction of methane dehydrogenation on new 20%La-10%Ce-20%Mg-50% glycine catalysts prepared by the SHS method to identify the optimal conditions for their preparation, concentration and ratio of metals, the influence of contact time and process temperature on the direction and mechanism of the reaction.
Держатели документа:
WKU
Доп.точки доступа:
Erkibaeva, M.K.
Aidarova, A.O.
Tungatarova, S.А.
Baizhumanova, T.S.
A92
Augaliev, D. B.
Oxidative dimerization of methane to C2 hydrocarbons. [Текст] / D. B. Augaliev, M. K. Erkibaeva, A. O. Aidarova // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 18-24
Рубрики: chemical Technology
Кл.слова (ненормированные):
ODM reaction -- C2 hydrocarbons -- SHS method -- temperature of reaction
Аннотация: The purpose of this work is to study the reaction of methane dehydrogenation on new 20%La-10%Ce-20%Mg-50% glycine catalysts prepared by the SHS method to identify the optimal conditions for their preparation, concentration and ratio of metals, the influence of contact time and process temperature on the direction and mechanism of the reaction.
Держатели документа:
WKU
Доп.точки доступа:
Erkibaeva, M.K.
Aidarova, A.O.
Tungatarova, S.А.
Baizhumanova, T.S.
373.
Подробнее
28.5
I-53
Ikhsanov, Y. S.
Amino acid , fatty acid and vitamin composition of rosa caninal. [Текст] / Y. S. Ikhsanov, K.M. Kusainova, G. Y. Tasmagambetova, N. T. Andasova, Y. A. Litvinenko // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 39-43
ББК 28.5
Рубрики: Botany
Кл.слова (ненормированные):
Rosa -- Rosa canina L -- Supercritical fluid extraction -- amino acid -- vitamins
Аннотация: This article examines the study of the quantitative composition of amino acids and vitamins in the fruits of the species of the genus Rosa widespread in Kazakhstan in the supercritical extract, isolated and the fruits of the Rosa canina plant, in order to establish the possibility of using and with the subsequent cultivation of the selected species.
Держатели документа:
WKU
Доп.точки доступа:
Kusainova, K.M.
Tasmagambetova, G.Y.
Andasova, N.T.
Litvinenko, Y.A.
I-53
Ikhsanov, Y. S.
Amino acid , fatty acid and vitamin composition of rosa caninal. [Текст] / Y. S. Ikhsanov, K.M. Kusainova, G. Y. Tasmagambetova, N. T. Andasova, Y. A. Litvinenko // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 39-43
Рубрики: Botany
Кл.слова (ненормированные):
Rosa -- Rosa canina L -- Supercritical fluid extraction -- amino acid -- vitamins
Аннотация: This article examines the study of the quantitative composition of amino acids and vitamins in the fruits of the species of the genus Rosa widespread in Kazakhstan in the supercritical extract, isolated and the fruits of the Rosa canina plant, in order to establish the possibility of using and with the subsequent cultivation of the selected species.
Держатели документа:
WKU
Доп.точки доступа:
Kusainova, K.M.
Tasmagambetova, G.Y.
Andasova, N.T.
Litvinenko, Y.A.
374.
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.
375.
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.
376.
Подробнее
24
M23
Mamyrbekova, А.
Study of kinetics of copper oxidation by electrolysis under non-stationary conditions. [Текст] / А. Mamyrbekova, А. Mamyrbekova, M. К. Kassymova, A. Zh. Aitbayeva, O. N. Chechina // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 54-59
ББК 24
Рубрики: chemistry
Кл.слова (ненормированные):
copper electro-oxidation -- copper (I) oxide -- copper (II) oxide -- unsteady electrolysis -- electrolyte -- polarisation curves
Аннотация: The nature of the anion electrolyte affects the rate of copper anodic oxidation, while the process occurs more efficiently in solutions of sulfate and sodium chloride and is accompanied by significant polarisation. Based on the study of kinetics the possibility of obtaining powders of metal oxide was shown, which further allowed to determine the parameters of the electrolysis process in non-stationary conditions in order to obtain highly dispersed materials based on copper oxides with specific physico-chemical properties.
Держатели документа:
WKU
Доп.точки доступа:
Mamyrbekova, А.
Kassymova, M.К.
Aitbayeva, A.Zh.
Chechina, O.N.
M23
Mamyrbekova, А.
Study of kinetics of copper oxidation by electrolysis under non-stationary conditions. [Текст] / А. Mamyrbekova, А. Mamyrbekova, M. К. Kassymova, A. Zh. Aitbayeva, O. N. Chechina // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 54-59
Рубрики: chemistry
Кл.слова (ненормированные):
copper electro-oxidation -- copper (I) oxide -- copper (II) oxide -- unsteady electrolysis -- electrolyte -- polarisation curves
Аннотация: The nature of the anion electrolyte affects the rate of copper anodic oxidation, while the process occurs more efficiently in solutions of sulfate and sodium chloride and is accompanied by significant polarisation. Based on the study of kinetics the possibility of obtaining powders of metal oxide was shown, which further allowed to determine the parameters of the electrolysis process in non-stationary conditions in order to obtain highly dispersed materials based on copper oxides with specific physico-chemical properties.
Держатели документа:
WKU
Доп.точки доступа:
Mamyrbekova, А.
Kassymova, M.К.
Aitbayeva, A.Zh.
Chechina, O.N.
377.
Подробнее
36
M15
Madet, G.
Research of malting properties of Kasakhstan tritikale grain varieties for use in the beverage industry. [Текст] / G. Madet // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 59-65
ББК 36
Рубрики: Пищевые производства
Кл.слова (ненормированные):
Malt -- barley -- triticale -- fermentation industry -- kvass -- kvass wort concentrate -- ethyl alcohol -- extract -- variety -- germination ability
Аннотация: In this regard, it is obvious that the performance of work related to theoretical and experimental research aimed at the development of new technological modes of preparation of malt from triticale is one of the urgent tasks, the decision of which, to create an assortment of drinks. The purpose of the research work is to study the malting properties of Kazakhstani varieties of triticale grain.
Держатели документа:
WKU
Доп.точки доступа:
Bayazitova, M.M.
M15
Madet, G.
Research of malting properties of Kasakhstan tritikale grain varieties for use in the beverage industry. [Текст] / G. Madet // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 59-65
Рубрики: Пищевые производства
Кл.слова (ненормированные):
Malt -- barley -- triticale -- fermentation industry -- kvass -- kvass wort concentrate -- ethyl alcohol -- extract -- variety -- germination ability
Аннотация: In this regard, it is obvious that the performance of work related to theoretical and experimental research aimed at the development of new technological modes of preparation of malt from triticale is one of the urgent tasks, the decision of which, to create an assortment of drinks. The purpose of the research work is to study the malting properties of Kazakhstani varieties of triticale grain.
Держатели документа:
WKU
Доп.точки доступа:
Bayazitova, M.M.
378.
Подробнее
24
M97
Mussina, А. S.
Development of the conditions for strong thallium amalgam. [Текст] / А. S. Mussina // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 65-70
ББК 24
Рубрики: chemistry
Кл.слова (ненормированные):
thallium amalgam -- chemical preparation -- storage -- decomposition -- sulfuric acid -- water -- wash liquid
Аннотация: It has been established that lNH2SO4 solution and distilled water can be used as a protective medium for a long-term storage (30-40 days) of thallium amalgam of eutectic composition (8.6 mas.%), without sliming of its surface and an insignificant change of its concentration. An inverse dependence between the decomposition reaction rate and the ratio of the solution volume per unit of the contact surface (V:S), which corresponds to the height of the liquid layer (h) above the amalgam, is observed. At h ~ 2.5 cm and higher, the reaction rate becomes stabilized. The value of metal loss during its storage for 10-15 days does not exceed 0.5-1.0 mas.% of the initial thallium content in the amalgam. It has been shown that the rate of dissolution of thallium from amalgam is rather low, and in sulfuric acid solution it is only slightly higher than that in water with all S:V ratios. A similar picture is observed upon thallium amalgam decomposition in the same media in an open vessel; the difference consists only in a higher K value (Table 4). Thus, with S:V = 1:2.5, in an open vessel K in lNH2SO4 makes up 10,5.1011 mol/cm2.sec, and in H2O – 7.3.1011 mol/cm2.sec, whereas in a closed vessel K in lNH2SO4 makes up 1,9.1011 mol/cm2.sec, and in H2O – 1.5.1011 mol/cm2.sec. For 40 days of thallium amalgam (8.54 mas.%) storage in 1NH2SO4 the loss of thallium has been 1.3 mas.%, and in the distilled water - 1 mas.%. The quantity of the dissolved metal increases in proportion to the experiment duration, which is characteristic for a zero-order reaction, and this dependence is observed for all S:V ratios from 1:1 to 1:7. Besides, a possibility to use some saturated hydrocarbons, wherein no sliming of thallium amalgam occurs, as a protective wash liquid has been shown.
Держатели документа:
WKU
Доп.точки доступа:
Baitasheva, G.U.
Myrzakhmetova, N.О.
Tagabergenova, Zh.A.
Gorbulicheva , E.P.
M97
Mussina, А. S.
Development of the conditions for strong thallium amalgam. [Текст] / А. S. Mussina // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 65-70
Рубрики: chemistry
Кл.слова (ненормированные):
thallium amalgam -- chemical preparation -- storage -- decomposition -- sulfuric acid -- water -- wash liquid
Аннотация: It has been established that lNH2SO4 solution and distilled water can be used as a protective medium for a long-term storage (30-40 days) of thallium amalgam of eutectic composition (8.6 mas.%), without sliming of its surface and an insignificant change of its concentration. An inverse dependence between the decomposition reaction rate and the ratio of the solution volume per unit of the contact surface (V:S), which corresponds to the height of the liquid layer (h) above the amalgam, is observed. At h ~ 2.5 cm and higher, the reaction rate becomes stabilized. The value of metal loss during its storage for 10-15 days does not exceed 0.5-1.0 mas.% of the initial thallium content in the amalgam. It has been shown that the rate of dissolution of thallium from amalgam is rather low, and in sulfuric acid solution it is only slightly higher than that in water with all S:V ratios. A similar picture is observed upon thallium amalgam decomposition in the same media in an open vessel; the difference consists only in a higher K value (Table 4). Thus, with S:V = 1:2.5, in an open vessel K in lNH2SO4 makes up 10,5.1011 mol/cm2.sec, and in H2O – 7.3.1011 mol/cm2.sec, whereas in a closed vessel K in lNH2SO4 makes up 1,9.1011 mol/cm2.sec, and in H2O – 1.5.1011 mol/cm2.sec. For 40 days of thallium amalgam (8.54 mas.%) storage in 1NH2SO4 the loss of thallium has been 1.3 mas.%, and in the distilled water - 1 mas.%. The quantity of the dissolved metal increases in proportion to the experiment duration, which is characteristic for a zero-order reaction, and this dependence is observed for all S:V ratios from 1:1 to 1:7. Besides, a possibility to use some saturated hydrocarbons, wherein no sliming of thallium amalgam occurs, as a protective wash liquid has been shown.
Держатели документа:
WKU
Доп.точки доступа:
Baitasheva, G.U.
Myrzakhmetova, N.О.
Tagabergenova, Zh.A.
Gorbulicheva , E.P.
379.
Подробнее
28
N16
Naguman, P.N.
Phytoncides in the composition of common bird cherry. [Текст] / P.N. Naguman // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 70-75
ББК 28
Рубрики: Biology
Кл.слова (ненормированные):
Bird cherry -- phytoncides -- plant -- bacteria -- protozoa -- useful properties
Аннотация: The presence of tannins and essential oil in the fruit has an anti-inflammatory effect, which is used to treat inflammatory processes in the gastrointestinal tract and dysentery. The infusion of cherry fruits has a destructive effect on microorganisms. Preparations of the fruits of the common cherry have an antiseptic effect. They are used in dental practice in the treatment of inflammatory processes of the oral mucosa, paradontosis, toothache and hypovitaminosis.
Держатели документа:
WKU
Доп.точки доступа:
Zhorabek, A.A.
Amanzholova, A.S.
Kulakov, I.V.
Rakhimbaeva, A.N.
N16
Naguman, P.N.
Phytoncides in the composition of common bird cherry. [Текст] / P.N. Naguman // News of national academy of sciences of the republic of Kazakhstan. . - 2021. - №3. - P. 70-75
Рубрики: Biology
Кл.слова (ненормированные):
Bird cherry -- phytoncides -- plant -- bacteria -- protozoa -- useful properties
Аннотация: The presence of tannins and essential oil in the fruit has an anti-inflammatory effect, which is used to treat inflammatory processes in the gastrointestinal tract and dysentery. The infusion of cherry fruits has a destructive effect on microorganisms. Preparations of the fruits of the common cherry have an antiseptic effect. They are used in dental practice in the treatment of inflammatory processes of the oral mucosa, paradontosis, toothache and hypovitaminosis.
Держатели документа:
WKU
Доп.точки доступа:
Zhorabek, A.A.
Amanzholova, A.S.
Kulakov, I.V.
Rakhimbaeva, A.N.
380.
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.
Page 38, Results: 424