Pub Date : 2020-09-09DOI: 10.6060/ivkkt.20206310.6301
Maria Е. Glazkova, M. V. Petrova, Yuliya S. Rodina, Sofia S. Rodina, Тatiana А. Аgeeva
The results of studying the spectral properties of zinc and cobalt meso-tetraphenyl-porphyrins included as the modifiers in polymethylmethacrylate, polystyrene and polyvinylchloride films are presented in this article for the first time. It was established that an inert polymer matrix of polyvinylchloride, block polystyrene and polymethylmethacrylate does not affect the spectral properties of tetrapyrrole macroheterocycles, which are included in it. In this case, insignificant bathochromic shift of the absorption bands of the metal complexes in the modified films is recorded, which is probably due to the presence of intermolecular interaction of the metalloporphyrin with the polymer matrix. The method of polymer producing is important for modification of polystyrene or polymethyl methacrylate films. The ignificant changes are observed in the electronic spectra of metalloporphyrins due to the interaction between the modifier and the residual amount of the radical polymerization initiator (benzoyl peroxide) used in the preparation of polymers. Earlier studies showed that the interaction of benzoyl peroxide with zinc and cobalt meso-tetraphenylporphyrinates in solution leads to the formation of the corresponding metalloisoporphyrinates. In this work, the possibility of such structures formation in a polymer matrix is shown for the first time. In this case, in the electronic absorption spectra of the modified films, as in solutions, bands appear in the near IR region. The fluorescent properties of modified films have been studied. It was shown that in the absence of interaction between the components in the film, metalloporphyrins introduced into the polymer matrix retain their ability to fluorescence.
{"title":"SPECTRAL PROPERTIES OF ZINC AND COBALT MESO-TETRAPHENYLPORPHYRINS IN POLYMER FILMS","authors":"Maria Е. Glazkova, M. V. Petrova, Yuliya S. Rodina, Sofia S. Rodina, Тatiana А. Аgeeva","doi":"10.6060/ivkkt.20206310.6301","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6301","url":null,"abstract":"The results of studying the spectral properties of zinc and cobalt meso-tetraphenyl-porphyrins included as the modifiers in polymethylmethacrylate, polystyrene and polyvinylchloride films are presented in this article for the first time. It was established that an inert polymer matrix of polyvinylchloride, block polystyrene and polymethylmethacrylate does not affect the spectral properties of tetrapyrrole macroheterocycles, which are included in it. In this case, insignificant bathochromic shift of the absorption bands of the metal complexes in the modified films is recorded, which is probably due to the presence of intermolecular interaction of the metalloporphyrin with the polymer matrix. The method of polymer producing is important for modification of polystyrene or polymethyl methacrylate films. The ignificant changes are observed in the electronic spectra of metalloporphyrins due to the interaction between the modifier and the residual amount of the radical polymerization initiator (benzoyl peroxide) used in the preparation of polymers. Earlier studies showed that the interaction of benzoyl peroxide with zinc and cobalt meso-tetraphenylporphyrinates in solution leads to the formation of the corresponding metalloisoporphyrinates. In this work, the possibility of such structures formation in a polymer matrix is shown for the first time. In this case, in the electronic absorption spectra of the modified films, as in solutions, bands appear in the near IR region. The fluorescent properties of modified films have been studied. It was shown that in the absence of interaction between the components in the film, metalloporphyrins introduced into the polymer matrix retain their ability to fluorescence.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75677182","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 : 2020-09-09DOI: 10.6060/ivkkt.20206310.6243
T. V. Burdikova, S. S. Ivshin, L. Zenitova
The paper presents the results of studies on the possibility of modifying the polyurethane matrix by the introduction into their structure of nanoscale fillers. The influence of the nature and content of nanosize additives of metal oxides (Al2O3, Fe2O3, CuO) on the physicomechanical properties of filled polyurethane compositions based on SKU PFL-100 prepolymer manufactured by Kazan Synthetic Rubber Plant JSC cured with 4,4'-methylene bis-(orthochloraniline) (MOCA) was studied. Dispersion analysis of the studied fillers is made. It was shown that the studied powders are prone to agglomeration. According to the specific surface area of the particles, the studied metal oxide powders are arranged as follows: Al2O3 - Fe2O3 - SiO2 - CuO. A discussion was made of the contribution of such factors as the area of interfacial contact, the structure and adsorption properties of the particle surface to the interaction at the oxide-polyurethane interface. It is shown that the decisive factor affecting the level of physical and mechanical properties is the nature of the filler (hydrophilicity, particle surface structure). The nature and concentration of nanosized particles of metal oxides were evaluated for the physicomechanical properties of the polymer under study. The initial and modified compositions were studied by thermogravimetric analysis. As a result of the studies, the basic laws that determine the effect of nanoscale additives of metal oxides on the properties of polymer systems are determined. It was shown that the introduction of 1% of the studied excipients is optimal. The highest values of physical and mechanical characteristics were recorded for polyurethane samples filled with copper oxide. Thermogravimetric analysis showed that by adding iron oxide additives it is possible to increase the heat-resistant properties of the polymer at operating temperatures up to 300 °C.
{"title":"STUDY OF INFLUENCE OF METAL NANOOXIDES ON CHARACTERISTICS OF COMPOSITE MATERIALS BASED ON POLYURETHANES","authors":"T. V. Burdikova, S. S. Ivshin, L. Zenitova","doi":"10.6060/ivkkt.20206310.6243","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6243","url":null,"abstract":"The paper presents the results of studies on the possibility of modifying the polyurethane matrix by the introduction into their structure of nanoscale fillers. The influence of the nature and content of nanosize additives of metal oxides (Al2O3, Fe2O3, CuO) on the physicomechanical properties of filled polyurethane compositions based on SKU PFL-100 prepolymer manufactured by Kazan Synthetic Rubber Plant JSC cured with 4,4'-methylene bis-(orthochloraniline) (MOCA) was studied. Dispersion analysis of the studied fillers is made. It was shown that the studied powders are prone to agglomeration. According to the specific surface area of the particles, the studied metal oxide powders are arranged as follows: Al2O3 - Fe2O3 - SiO2 - CuO. A discussion was made of the contribution of such factors as the area of interfacial contact, the structure and adsorption properties of the particle surface to the interaction at the oxide-polyurethane interface. It is shown that the decisive factor affecting the level of physical and mechanical properties is the nature of the filler (hydrophilicity, particle surface structure). The nature and concentration of nanosized particles of metal oxides were evaluated for the physicomechanical properties of the polymer under study. The initial and modified compositions were studied by thermogravimetric analysis. As a result of the studies, the basic laws that determine the effect of nanoscale additives of metal oxides on the properties of polymer systems are determined. It was shown that the introduction of 1% of the studied excipients is optimal. The highest values of physical and mechanical characteristics were recorded for polyurethane samples filled with copper oxide. Thermogravimetric analysis showed that by adding iron oxide additives it is possible to increase the heat-resistant properties of the polymer at operating temperatures up to 300 °C.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"225 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73930209","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 : 2020-09-09DOI: 10.6060/ivkkt.20206310.6233
S. Popova, G. Matafonova, V. Batoev
In present work, we have studied the kinetic fundamentals of sonophotochemical oxidation of emerging organic contaminants, atrazine and bisphenol A, in model aqueous solutions, simultaneously exposed to high-frequency ultrasound (US, 1.7 MHz) and ultraviolet light-emitting diodes (UV LEDs, 365 nm) in the absence and presence of persulfate (S2O82-) oxidant. Synergistic indices were calculated to assess a synergistic effect in the hybrid oxidation systems. It was found that the hybrid system {UV/US/S2O82-} exhibited the synergistic effect and was the most efficient for degrading bisphenol A in a raw: UV/US/S2O82- > UV/S2O82- > US/UV > US/S2O82- >> UV > US. In case of atrazine, no ultrasound effect was observed and the efficiencies of {UV/US/S2O82-} and {UV S2O82-} systems in terms of degradation rates were similar. In these oxidation systems, more than 90% of a contaminant was removed after 30 min treatment. Meanwhile, degradation rates for atrazine were higher than those wich were found for bisphenol A. This indicates a predomination of sulfate anion radicals, which react with bisphenol A rather slowly compared to atrazine. A synergism was also found under sonophotolysis of both contaminants without persulfate; however, this process requires a more prolonged irradiation time (~20% degraded in 40 min), hence, it is less energy-effective. The obtained results are promising for application of UV LEDs and high-frequency ultrasound in persulfate-based advanced oxidation processes to degrade organic contaminants in natural water and wastewater.
{"title":"SONOPHOTOCHEMICAL OXIDATION OF ORGANIC CONTAMINANTS IN AQUEOUS SOLUTIONS USING PERSULFATE","authors":"S. Popova, G. Matafonova, V. Batoev","doi":"10.6060/ivkkt.20206310.6233","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6233","url":null,"abstract":"In present work, we have studied the kinetic fundamentals of sonophotochemical oxidation of emerging organic contaminants, atrazine and bisphenol A, in model aqueous solutions, simultaneously exposed to high-frequency ultrasound (US, 1.7 MHz) and ultraviolet light-emitting diodes (UV LEDs, 365 nm) in the absence and presence of persulfate (S2O82-) oxidant. Synergistic indices were calculated to assess a synergistic effect in the hybrid oxidation systems. It was found that the hybrid system {UV/US/S2O82-} exhibited the synergistic effect and was the most efficient for degrading bisphenol A in a raw: UV/US/S2O82- > UV/S2O82- > US/UV > US/S2O82- >> UV > US. In case of atrazine, no ultrasound effect was observed and the efficiencies of {UV/US/S2O82-} and {UV S2O82-} systems in terms of degradation rates were similar. In these oxidation systems, more than 90% of a contaminant was removed after 30 min treatment. Meanwhile, degradation rates for atrazine were higher than those wich were found for bisphenol A. This indicates a predomination of sulfate anion radicals, which react with bisphenol A rather slowly compared to atrazine. A synergism was also found under sonophotolysis of both contaminants without persulfate; however, this process requires a more prolonged irradiation time (~20% degraded in 40 min), hence, it is less energy-effective. The obtained results are promising for application of UV LEDs and high-frequency ultrasound in persulfate-based advanced oxidation processes to degrade organic contaminants in natural water and wastewater.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77149286","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 : 2020-09-09DOI: 10.6060/ivkkt.20206310.6063
Guseyn R. Gurbanov, Saida M. Pashaeva, M. Adygezalova
Using the gravimetric method, the inhibitory efficiency of the combined inhibitor with respect to hydrogen sulfide and carbon dioxide corrosion of St3 steel in model-produced water MI was studied. Corrosion tests were carried out in 0.5 l sealed vessels on St3 samples of size 30×20×1. Gossypol resin + MARZA was used as a multifunctional combined inhibitor. Diesel fuel and kerosene were used as solvent. It has been established that the protective effect of using a multifunctional combined inhibitor in formation water with oil containing hydrogen sulphide and carbon dioxide using kerosene as a solvent ranges from 75 to 96 and for diesel as 80 to 100. The combined inhibitor allows to achieve in the MI medium containing hydrogen sulfide and carbon dioxide in the process of daily testing the corrosion rate of steel is about 0.04 g/ m2∙h only in a concentration of not less than 70 mg/l. However, with an increase in the duration of the test by an order of magnitude, a similar corrosion rate is observed already at an inhibitor concentration of 50 mg/l. The same is characteristic of carbon dioxide and hydrogen sulfide - carbon dioxide solutions. The bactericidal properties of the combined inhibitor with respect to two types of Desulfovibriodesulfuricans and Desulfomicrobium sulfate-reducing bacteria were studied. The effect of the inhibitor on the number of bacterial cells and the formation of hydrogen sulfide in Postgate nutrient medium “B” was evaluated. It has been shown that the combined inhibitor exhibits a bacteriostatic effect on to sulphate-reducing bacteria. It was revealed that the degree of suppression of the number of microorganisms Desulfovibriodesulfuricans at a concentration of the combined inhibitor 100.0 mg/l is higher than Desulfomicrobium. In the latter case, to achieve this effect, 120.0 mg/l concentration of the combined inhibitor is required. The studied combination inhibitor causes inhibition of hydrogen diffusion in steel St3 in the MI medium saturated with H2S and CO2 separately and together, and contributes to preserving the ductile properties of the steel St3 after exposure to solutions compared to non-inhibited media.
{"title":"STUDY OF UNIVERSAL COMBINED INHIBITOR FOR OIL AND GAS INDUSTRY","authors":"Guseyn R. Gurbanov, Saida M. Pashaeva, M. Adygezalova","doi":"10.6060/ivkkt.20206310.6063","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6063","url":null,"abstract":"Using the gravimetric method, the inhibitory efficiency of the combined inhibitor with respect to hydrogen sulfide and carbon dioxide corrosion of St3 steel in model-produced water MI was studied. Corrosion tests were carried out in 0.5 l sealed vessels on St3 samples of size 30×20×1. Gossypol resin + MARZA was used as a multifunctional combined inhibitor. Diesel fuel and kerosene were used as solvent. It has been established that the protective effect of using a multifunctional combined inhibitor in formation water with oil containing hydrogen sulphide and carbon dioxide using kerosene as a solvent ranges from 75 to 96 and for diesel as 80 to 100. The combined inhibitor allows to achieve in the MI medium containing hydrogen sulfide and carbon dioxide in the process of daily testing the corrosion rate of steel is about 0.04 g/ m2∙h only in a concentration of not less than 70 mg/l. However, with an increase in the duration of the test by an order of magnitude, a similar corrosion rate is observed already at an inhibitor concentration of 50 mg/l. The same is characteristic of carbon dioxide and hydrogen sulfide - carbon dioxide solutions. The bactericidal properties of the combined inhibitor with respect to two types of Desulfovibriodesulfuricans and Desulfomicrobium sulfate-reducing bacteria were studied. The effect of the inhibitor on the number of bacterial cells and the formation of hydrogen sulfide in Postgate nutrient medium “B” was evaluated. It has been shown that the combined inhibitor exhibits a bacteriostatic effect on to sulphate-reducing bacteria. It was revealed that the degree of suppression of the number of microorganisms Desulfovibriodesulfuricans at a concentration of the combined inhibitor 100.0 mg/l is higher than Desulfomicrobium. In the latter case, to achieve this effect, 120.0 mg/l concentration of the combined inhibitor is required. The studied combination inhibitor causes inhibition of hydrogen diffusion in steel St3 in the MI medium saturated with H2S and CO2 separately and together, and contributes to preserving the ductile properties of the steel St3 after exposure to solutions compared to non-inhibited media.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73214405","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 : 2020-09-09DOI: 10.6060/ivkkt.20206310.6234
A. Aripbaeva, Zhumahan U. Mirkhalykov, R. Kaldybaev, Oscar I. Koyfman, Y. Bazarov, S. Stepanova, S. Stepanov
The article proposes a technique for experimental studies of contact zones between threads in woven reinforcing frames of pressure fire hoses using a JSM-6490LV scanning electron microscope and statistical methods, on the basis of which the coefficients of vertical crumpling of threads, coefficients characterizing the lengths of contact zones between threads in fractions of the diameters of the warp and weft threads, the account of which is necessary for a more accurate determination of the bursting pressures in the pressure head fire hoses. Burst pressure is regulated by GOST R 51049-97 and is an important strength parameter of a pressure head fire hose, characterizing its ability to resist destruction under the influence of the internal hydraulic pressure of a fire extinguishing fluid. The influence of such parameters of a woven reinforcing frame made of polyester threads based on polyethylene terephthalate (PET), as the breaking force of the weft threads (threads laid along the circumference of the sleeve), the radius of the sleeve, geometric densities along the warp and weft, the coefficients of vertical crumpling, has been studied. and the diameters of the warp and weft threads, the coefficients characterizing the lengths of the contact zones between the threads in fractions of the diameters of the warp and weft threads by the value of the bursting pressure in the latex pressure fire hose manufactured by BEREG, designed for a working pressure of 1.6 MPa. As a result of the study, it was established: the bursting pressure of the pressure head fire hose significantly depends on the geometric densities along the base and weft of the fabric of the reinforcing frame (with an increase (decrease) in geometric densities, the calculated bursting pressure of the hose falls (increases)); the bursting pressure of the sleeve is directly proportional to the bursting force of the weft threads and inversely proportional to the radius of the pressure head fire hose with all its other parameters constant, and the dependence of the bursting pressure on these parameters is significant; with an increase in such parameters of the woven reinforcing frame of the pressure head fire hose as the diameters of the warp and weft threads, their vertical crushing, the length of the contact zones between the threads, the bursting pressure increases, which indicates the need to take these parameters into account in the strength calculation of the woven reinforcing frames of the fire hoses . The results of the study must be taken into account when designing new types of these technical products.
本文提出了一种利用JSM-6490LV型扫描电子显微镜和统计学方法对高压消防水带机织加强架螺纹间接触区域进行实验研究的方法，在此基础上，得到了螺纹的垂直卷曲系数、经纬螺纹直径分数中螺纹间接触区域长度的表征系数、为了更准确地确定压头消防软管的爆破压力，必须对其进行计算。破裂压力由GOST R 51049-97规定，是压力头消防水带的重要强度参数，表征其在灭火液内部液压影响下抵抗破坏的能力。研究了纬线(沿套周布放的线)的断裂力、套的半径、经纬方向的几何密度、垂直起皱系数等参数对涤纶丝机织增强框架性能的影响。经纬线直径，用BEREG公司生产的工作压力为1.6 MPa的乳胶压力消防水带的破裂压力值表示经纬线直径的分数中螺纹间接触区长度的系数。研究结果表明:压力头消防水带的破裂压力与增强框架织物基底和纬向的几何密度显著相关(随着几何密度的增大(减小)，计算出的破裂压力减小(增大));在其他参数不变的情况下，套筒爆破压力与纬线爆破力成正比，与压力头消防水带半径成反比，爆破压力与这些参数的相关性显著;随着压力头消防水带编织加强框架经纬线直径、垂直破碎线、线间接触区长度等参数的增加，破裂压力增大，说明在进行消防水带编织加强框架强度计算时需要考虑这些参数。在设计这些技术产品的新类型时，必须考虑研究结果。
{"title":"INVESTIGATION OF CHARACTERISTICS OF WOVEN REINFORCING FRAMES OF PRESSURE FIRE HOSES AND THEIR INFLUENCE ON VALUES OF INTERNAL BURSTING PRESSURES","authors":"A. Aripbaeva, Zhumahan U. Mirkhalykov, R. Kaldybaev, Oscar I. Koyfman, Y. Bazarov, S. Stepanova, S. Stepanov","doi":"10.6060/ivkkt.20206310.6234","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6234","url":null,"abstract":"The article proposes a technique for experimental studies of contact zones between threads in woven reinforcing frames of pressure fire hoses using a JSM-6490LV scanning electron microscope and statistical methods, on the basis of which the coefficients of vertical crumpling of threads, coefficients characterizing the lengths of contact zones between threads in fractions of the diameters of the warp and weft threads, the account of which is necessary for a more accurate determination of the bursting pressures in the pressure head fire hoses. Burst pressure is regulated by GOST R 51049-97 and is an important strength parameter of a pressure head fire hose, characterizing its ability to resist destruction under the influence of the internal hydraulic pressure of a fire extinguishing fluid. The influence of such parameters of a woven reinforcing frame made of polyester threads based on polyethylene terephthalate (PET), as the breaking force of the weft threads (threads laid along the circumference of the sleeve), the radius of the sleeve, geometric densities along the warp and weft, the coefficients of vertical crumpling, has been studied. and the diameters of the warp and weft threads, the coefficients characterizing the lengths of the contact zones between the threads in fractions of the diameters of the warp and weft threads by the value of the bursting pressure in the latex pressure fire hose manufactured by BEREG, designed for a working pressure of 1.6 MPa. As a result of the study, it was established: the bursting pressure of the pressure head fire hose significantly depends on the geometric densities along the base and weft of the fabric of the reinforcing frame (with an increase (decrease) in geometric densities, the calculated bursting pressure of the hose falls (increases)); the bursting pressure of the sleeve is directly proportional to the bursting force of the weft threads and inversely proportional to the radius of the pressure head fire hose with all its other parameters constant, and the dependence of the bursting pressure on these parameters is significant; with an increase in such parameters of the woven reinforcing frame of the pressure head fire hose as the diameters of the warp and weft threads, their vertical crushing, the length of the contact zones between the threads, the bursting pressure increases, which indicates the need to take these parameters into account in the strength calculation of the woven reinforcing frames of the fire hoses . The results of the study must be taken into account when designing new types of these technical products.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89531546","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 : 2020-09-08DOI: 10.6060/ivkkt.20206310.6201
S. M. Safarmamadov, Dilovar Ch. Mirzokhonov, K. S. Mabatkadamzoda
Using potentiometric titration data, titration curves of the protonated form of 2-methylimidazole [H2-MI]+ in water and water-alcohol solutions were constructed. Forms of formation curves correspond to weak monobasic acids. The value of the formation function () for the studied systems varies between 0.45-0.87, which corresponds to the formation of one protonated form of 2-methylimidazole in aqueous and aqueous - alcoholic solutions. The acid dissociation constant (pKa) of 2-methylimidazole at 298 K was determined by the pH - metric method in aqueous and aqueous - methanol (ethanol) solutions at different contents of the organic solvent. It was revealed that the maximum proportion of molecular form accumulation falls on pH 10-10.5. Below pH 10, the protonated form of 2-methylimidazole begins to accumulate in the solution. Starting from pH = 7.2-methylimidazole exists completely in protonated form in solution. With an increase in the concentration of alcohol in solution, an increase in the acidic properties of the protonated form of 2-methylimidazole is observed. The pKa value of 2-methylimidazole in aqueous ethanol solutions is higher than that of aqueous methanol. The potentiometric method was used to study the complexation of cadmium (II) with 2-methylimidazole (2-MI) at 278-318 K. The effect of the nature and composition of the aqueous-organic solution on the stability of the complexes formed is established. It was revealed that during the interaction of cadmium (II) with 2-methylimidazole in aqueous and aqueous-alcoholic solutions four complex forms are formed. For each complex form, stability constants are found depending on the temperature and the content of non-aqueous solvent. It is shown that when methanol is added to water, an increase in the stability of all complex forms is observed. In contrast to water-methanol solutions in water-ethanol solutions, in addition to the complex particle [CdL4]2+, the stability of other complex forms pass through a minimum. Based on our own and published data, we conclude that the degree of influence that an organic solvent has on the stability of complexes cadmium (II) largely depends on changes in the solvation condition of the ligand molecule and the central atom.
{"title":"The COMPLEX FORMATION OF CADMIUM (II) WITH 2-METHYLIMIDAZOLE IN AQUEOUS AND AQUEOS-ALCOHOL SOLUTIONS","authors":"S. M. Safarmamadov, Dilovar Ch. Mirzokhonov, K. S. Mabatkadamzoda","doi":"10.6060/ivkkt.20206310.6201","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6201","url":null,"abstract":"Using potentiometric titration data, titration curves of the protonated form of 2-methylimidazole [H2-MI]+ in water and water-alcohol solutions were constructed. Forms of formation curves correspond to weak monobasic acids. The value of the formation function () for the studied systems varies between 0.45-0.87, which corresponds to the formation of one protonated form of 2-methylimidazole in aqueous and aqueous - alcoholic solutions. The acid dissociation constant (pKa) of 2-methylimidazole at 298 K was determined by the pH - metric method in aqueous and aqueous - methanol (ethanol) solutions at different contents of the organic solvent. It was revealed that the maximum proportion of molecular form accumulation falls on pH 10-10.5. Below pH 10, the protonated form of 2-methylimidazole begins to accumulate in the solution. Starting from pH = 7.2-methylimidazole exists completely in protonated form in solution. With an increase in the concentration of alcohol in solution, an increase in the acidic properties of the protonated form of 2-methylimidazole is observed. The pKa value of 2-methylimidazole in aqueous ethanol solutions is higher than that of aqueous methanol. The potentiometric method was used to study the complexation of cadmium (II) with 2-methylimidazole (2-MI) at 278-318 K. The effect of the nature and composition of the aqueous-organic solution on the stability of the complexes formed is established. It was revealed that during the interaction of cadmium (II) with 2-methylimidazole in aqueous and aqueous-alcoholic solutions four complex forms are formed. For each complex form, stability constants are found depending on the temperature and the content of non-aqueous solvent. It is shown that when methanol is added to water, an increase in the stability of all complex forms is observed. In contrast to water-methanol solutions in water-ethanol solutions, in addition to the complex particle [CdL4]2+, the stability of other complex forms pass through a minimum. Based on our own and published data, we conclude that the degree of influence that an organic solvent has on the stability of complexes cadmium (II) largely depends on changes in the solvation condition of the ligand molecule and the central atom. \u0000 \u0000 ","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87192744","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 : 2020-09-08DOI: 10.6060/ivkkt.20206310.6257
S. Makarov, E. Pokrovskaya, D. Salnikov, A. V. Amanova
The influence of L-cysteine and N-acetyl-L-cysteine on the stability and reducing activity of thiourea dioxide (NH2)2CSO2 (TDO) in the reaction with azo dye Orange II has been studied. The addition of L-cysteine and N-acetyl-L-cysteine leads to the increase in reducing activity of TDO in weakly acidic, neutral and weakly alkaline solutions, but does not influence its reducing activity in strongly alkaline solutions. In alkaline solutions, the rate of reduction of Orange II is increasing, but the influence of additives of thiol acids is decreasing. The activating effect of N-ace-tyl-L-cysteine is weaker than the effect of L-cysteine, that can be explained by the differences of pKa of these acids. Indeed, the reducing activity of thiols depends on the concentration of thiolate-ions in solutions. Since pKa of cysteine (8.30) is significantly less than pKa of N-acetyl-L-cysteine (9.52), concentration of thiolate-ions in cysteine solutions is higher. Therefore, reducing activity of L-cysteine is higher. The influence of L-cysteine and N-acetyl-L-cysteine on the reaction of TDO with Orange II is different from the influence of aminoacid glycine: in neutral solutions glycine decreases the rate of reaction. The interaction of TDO with L-cysteine in weakly acidic, neutral and weakly alkaline solutions is accompanied by the oxidation of L-cysteine to cysteinesulfenic acid and reduction of TDO to thiourea monoxide (NH2)2CSO. Then cysteinesulfenic acid reacts with L-cysteine with formation of cystine. The reaction studied here is the first example of reduction of TDO by sulfur-containing compounds.
{"title":"INFLUENCE OF L-CYSTEINE AND N-ACETYL-L-CYSTEINE ON REDUCING ACTIVITY OF THIOUREA DIOXIDE IN AQUEOUS SOLUTIONS","authors":"S. Makarov, E. Pokrovskaya, D. Salnikov, A. V. Amanova","doi":"10.6060/ivkkt.20206310.6257","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6257","url":null,"abstract":"The influence of L-cysteine and N-acetyl-L-cysteine on the stability and reducing activity of thiourea dioxide (NH2)2CSO2 (TDO) in the reaction with azo dye Orange II has been studied. The addition of L-cysteine and N-acetyl-L-cysteine leads to the increase in reducing activity of TDO in weakly acidic, neutral and weakly alkaline solutions, but does not influence its reducing activity in strongly alkaline solutions. In alkaline solutions, the rate of reduction of Orange II is increasing, but the influence of additives of thiol acids is decreasing. The activating effect of N-ace-tyl-L-cysteine is weaker than the effect of L-cysteine, that can be explained by the differences of pKa of these acids. Indeed, the reducing activity of thiols depends on the concentration of thiolate-ions in solutions. Since pKa of cysteine (8.30) is significantly less than pKa of N-acetyl-L-cysteine (9.52), concentration of thiolate-ions in cysteine solutions is higher. Therefore, reducing activity of L-cysteine is higher. The influence of L-cysteine and N-acetyl-L-cysteine on the reaction of TDO with Orange II is different from the influence of aminoacid glycine: in neutral solutions glycine decreases the rate of reaction. The interaction of TDO with L-cysteine in weakly acidic, neutral and weakly alkaline solutions is accompanied by the oxidation of L-cysteine to cysteinesulfenic acid and reduction of TDO to thiourea monoxide (NH2)2CSO. Then cysteinesulfenic acid reacts with L-cysteine with formation of cystine. The reaction studied here is the first example of reduction of TDO by sulfur-containing compounds.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84245349","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 : 2020-09-08DOI: 10.6060/ivkkt.20206310.6263
A. A. Maksyutova, E. R. Khaynasova, Yuriy S. Zimin
The ultraviolet spectroscopy method has been applied to study the kinetics of the ozone reactions with nitrogenous bases (NB), namely adenine and cytosine in aqueous solutions. At the first research stage, the range of NB working concentrations has been determined. It was found that linear dependences between optical densities and concentrations of nitrogenous bases aqueous solutions are quite reliable, with correlation coefficients r ≥ 0.998, are satisfied up to [NB] = 2.3 ∙ 10–4 mol/l. According to the Bouguer-Lambert-Beer law, adenine and cytosine extinction coefficients in aqueous solutions were determined and subsequently used to calculate their residual concentrations. At the next stage, the kinetics of nitrogenous bases ozonized oxidation was studied with equal initial concentrations of the starting substances ([NB]0 = [О3]0). The results revealed that the kinetic consumption curves of the starting reagents are fairly well linearized (r ≥ 0.996) in the second-order reaction equation coordinates. As found with the bubbling installation, 1 mol of the absorbed ozone falls on 1 mol of the used NB. Thus, the reactions of ozone with adenine and cytosine explicitly proceed according to the second-order kinetic laws (the first – according to О3 and the first – according to NB). The rate constants were calculated by the integral reaction equations, the values of which indicate a higher ozone reactivity in relation to nitrogen bases. The temperature dependences of the second-order rate constants was studied ranging 285-309 K, and the activation parameters (pre-exponential factors and activation energies) of the ozone reactions with adenine and cytosine in aqueous solutions were determined.
{"title":"KINETICS OF OZONE REACTIONS WITH ADENINE AND CYTOSINE IN AQUEOUS SOLUTIONS","authors":"A. A. Maksyutova, E. R. Khaynasova, Yuriy S. Zimin","doi":"10.6060/ivkkt.20206310.6263","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6263","url":null,"abstract":"The ultraviolet spectroscopy method has been applied to study the kinetics of the ozone reactions with nitrogenous bases (NB), namely adenine and cytosine in aqueous solutions. At the first research stage, the range of NB working concentrations has been determined. It was found that linear dependences between optical densities and concentrations of nitrogenous bases aqueous solutions are quite reliable, with correlation coefficients r ≥ 0.998, are satisfied up to [NB] = 2.3 ∙ 10–4 mol/l. According to the Bouguer-Lambert-Beer law, adenine and cytosine extinction coefficients in aqueous solutions were determined and subsequently used to calculate their residual concentrations. At the next stage, the kinetics of nitrogenous bases ozonized oxidation was studied with equal initial concentrations of the starting substances ([NB]0 = [О3]0). The results revealed that the kinetic consumption curves of the starting reagents are fairly well linearized (r ≥ 0.996) in the second-order reaction equation coordinates. As found with the bubbling installation, 1 mol of the absorbed ozone falls on 1 mol of the used NB. Thus, the reactions of ozone with adenine and cytosine explicitly proceed according to the second-order kinetic laws (the first – according to О3 and the first – according to NB). The rate constants were calculated by the integral reaction equations, the values of which indicate a higher ozone reactivity in relation to nitrogen bases. The temperature dependences of the second-order rate constants was studied ranging 285-309 K, and the activation parameters (pre-exponential factors and activation energies) of the ozone reactions with adenine and cytosine in aqueous solutions were determined.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"6 47","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91508417","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 : 2020-09-08DOI: 10.6060/ivkkt.20206310.6224
Yulia I. Matyushkina, A. A. Shabarin
The anion-exchange extraction of thiocyanate, chloride and iodide cadmium complexes by solutions of quaternary ammonium salts chlorides in organic solvents (toluene, carbon tetrachloride, ethyl acetate, isobutyl alcohol, nitrobenzene) was studied. Extraction involves solutions of alkyl dimethylbenzylammonium chlorides (R-N+(CH3)2-CH2C6H5-Cl-) and alkyl dimethylethyl-benzylammonium (R-N+(CH3)2-CH2-CH2C6H5-Cl-), where R is a straight alkyl chain, mainly C12 - C14. The composition of the cadmium anionic complexes was established by the analysis of the calibration curves E = f (pCCd (II)) constructed from cadmium sulfate solutions against the background of various contents of thiocyanate, chloride and iodide ions (ndicator electrode - ion-selective electrode with a membrane, which based on a nitrobenzene solution of tetradecylammonium bromide). The extraction process is estimated quantitatively using a distribution coefficient (D). The value of D is calculated taking into account the cadmium concentration in the aqueous phase before and after extraction. The dependence of the distribution coefficient on the organic solvent dielectric constant, the concentration and stability of the anionic complexes of cadmium is shown. So, for the indicated cadmium acidocomplexes, the minimum D values were obtained using low-polar toluene and carbon tetrachloride, and the maximum values were obtained using highly polar isobutyl alcohol and nitrobenzene. If the concentration of cadmium (II) is reduced by a factor of 100 for the cadmium rhodanide and iodide complexes, the value of D decreases by 1.6-1.9 times, for the chloride complex, by 1.2 times in the case of polar isobutyl alcohol and nitrobenzene, and 2.9-3.5 times in the case of low-polar solvents. It was experimentally established that in the series [Cd(SCN)4]2- - [CdI4]2-- [CdCl4]2- the value of D decreases for all the studied systems. The observed regularity is related both to the stability of the corresponding cadmium (II) complexes in aqueous solutions and to their hydrophobicity.
研究了季铵盐氯化物在有机溶剂(甲苯、四氯化碳、乙酸乙酯、异丁醇、硝基苯)中的阴离子交换萃取硫氰酸盐、氯化物和碘化镉配合物。萃取采用烷基二甲基苄基氯化铵(R- n +(CH3)2-CH2C6H5-Cl-)和烷基二甲基乙基苄基铵(R- n +(CH3)2-CH2-CH2C6H5-Cl-)溶液，其中R为直烷基链，主要为C12 - C14。通过分析不同硫氰酸盐、氯离子和碘离子背景下的硫酸镉溶液(指示电极-带膜离子选择电极，以硝基苯十四烷基溴化铵溶液为基础)构建的校准曲线E = f (pCCd (II))，确定了镉阴离子配合物的组成。通过分配系数(D)对萃取过程进行定量估计。D值的计算考虑了萃取前后水相中镉的浓度。研究了镉离子的分布系数与有机溶剂介电常数、镉离子离子配合物的浓度和稳定性的关系。因此，对于指示的镉酸配合物，使用低极性甲苯和四氯化碳获得的D值最小，使用高极性异丁醇和硝基苯获得的D值最大。如果罗达尼镉和碘化物络合物的镉(II)浓度降低100倍，则氯络合物的D值降低1.6-1.9倍，极性异丁醇和硝基苯的D值降低1.2倍，低极性溶剂的D值降低2.9-3.5倍。实验证明，在[Cd(SCN)4]2- - [CdI4]2-- [CdCl4]2-系列中，所有研究体系的D值都减小。所观察到的规律性与相应的镉(II)配合物在水溶液中的稳定性和它们的疏水性有关。
{"title":"EXTRACTION OF ANIONIC CADMIUM COMPLEXES WITH ORGANIC SOLUTIONS OF QUATERNARY AMMONIUM SALTS","authors":"Yulia I. Matyushkina, A. A. Shabarin","doi":"10.6060/ivkkt.20206310.6224","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6224","url":null,"abstract":"The anion-exchange extraction of thiocyanate, chloride and iodide cadmium complexes by solutions of quaternary ammonium salts chlorides in organic solvents (toluene, carbon tetrachloride, ethyl acetate, isobutyl alcohol, nitrobenzene) was studied. Extraction involves solutions of alkyl dimethylbenzylammonium chlorides (R-N+(CH3)2-CH2C6H5-Cl-) and alkyl dimethylethyl-benzylammonium (R-N+(CH3)2-CH2-CH2C6H5-Cl-), where R is a straight alkyl chain, mainly C12 - C14. The composition of the cadmium anionic complexes was established by the analysis of the calibration curves E = f (pCCd (II)) constructed from cadmium sulfate solutions against the background of various contents of thiocyanate, chloride and iodide ions (ndicator electrode - ion-selective electrode with a membrane, which based on a nitrobenzene solution of tetradecylammonium bromide). The extraction process is estimated quantitatively using a distribution coefficient (D). The value of D is calculated taking into account the cadmium concentration in the aqueous phase before and after extraction. The dependence of the distribution coefficient on the organic solvent dielectric constant, the concentration and stability of the anionic complexes of cadmium is shown. So, for the indicated cadmium acidocomplexes, the minimum D values were obtained using low-polar toluene and carbon tetrachloride, and the maximum values were obtained using highly polar isobutyl alcohol and nitrobenzene. If the concentration of cadmium (II) is reduced by a factor of 100 for the cadmium rhodanide and iodide complexes, the value of D decreases by 1.6-1.9 times, for the chloride complex, by 1.2 times in the case of polar isobutyl alcohol and nitrobenzene, and 2.9-3.5 times in the case of low-polar solvents. It was experimentally established that in the series [Cd(SCN)4]2- - [CdI4]2-- [CdCl4]2- the value of D decreases for all the studied systems. The observed regularity is related both to the stability of the corresponding cadmium (II) complexes in aqueous solutions and to their hydrophobicity.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90062526","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 : 2020-09-08DOI: 10.6060/ivkkt.20206310.6235
N. Shabelskaya, E. Vasilieva, E. A. Yakovenko, Y. Podkovyrina, A. Skorynina
The paper discusses technological methods for obtaining a luminescent material from phosphogypsum. The obtained materials were characterized using X-ray phase analysis, X-ray fluorescence analysis, and electron microscopy. The elemental composition of the samples was determined using a laboratory micro-fluorimeter. In the course of the study, the technological conditions for converting the main part of phosphogypsum into a luminescent material based on calcium sulfide were established. It is shown that the process of obtaining luminescent CaS consists of dehydration stages: the initial stage, carried out at a temperature of 373 K to remove physically bound water, and the final stage, at a temperature of 1073 K – to remove crystallization water, as well as the stage of phosphogypsum reduced at a temperature of 1173 K for 0.5 h. An environmentally friendly material-sucrose-is considered as a reducing agent. It is shown that in the case of changing the technological modes of reduction the luminescent material cannot be obtained. Conducting the reduction process at a temperature of 773 K is accompanied by obtaining a sample contaminated with products of incomplete decomposition of the organic component of the charge. In this case, the sample does not contain calcium sulfide. Under prolonged isothermal exposure at a temperature of 1173 K, repeated oxidation of samples with loss of luminescence ability was observed. Optimal technological modes for obtaining materials with phosphor properties are formulated. According to the results of X-ray phase analysis, samples that do not show luminescence capacity contain calcium sulfate as the main phase. Samples-phosphors consist of a mixture of calcium sulfate and sulfide. Results obtained open up wide opportunities for involving in the re-processing of production waste to obtain cheap products in demand.
{"title":"FEATURES OF SYNTHESIS OF INORGANIC LUMINESCENT MATERIAL FROM PHOSPHOGYPSUM","authors":"N. Shabelskaya, E. Vasilieva, E. A. Yakovenko, Y. Podkovyrina, A. Skorynina","doi":"10.6060/ivkkt.20206310.6235","DOIUrl":"https://doi.org/10.6060/ivkkt.20206310.6235","url":null,"abstract":"The paper discusses technological methods for obtaining a luminescent material from phosphogypsum. The obtained materials were characterized using X-ray phase analysis, X-ray fluorescence analysis, and electron microscopy. The elemental composition of the samples was determined using a laboratory micro-fluorimeter. In the course of the study, the technological conditions for converting the main part of phosphogypsum into a luminescent material based on calcium sulfide were established. It is shown that the process of obtaining luminescent CaS consists of dehydration stages: the initial stage, carried out at a temperature of 373 K to remove physically bound water, and the final stage, at a temperature of 1073 K – to remove crystallization water, as well as the stage of phosphogypsum reduced at a temperature of 1173 K for 0.5 h. An environmentally friendly material-sucrose-is considered as a reducing agent. It is shown that in the case of changing the technological modes of reduction the luminescent material cannot be obtained. Conducting the reduction process at a temperature of 773 K is accompanied by obtaining a sample contaminated with products of incomplete decomposition of the organic component of the charge. In this case, the sample does not contain calcium sulfide. Under prolonged isothermal exposure at a temperature of 1173 K, repeated oxidation of samples with loss of luminescence ability was observed. Optimal technological modes for obtaining materials with phosphor properties are formulated. According to the results of X-ray phase analysis, samples that do not show luminescence capacity contain calcium sulfate as the main phase. Samples-phosphors consist of a mixture of calcium sulfate and sulfide. Results obtained open up wide opportunities for involving in the re-processing of production waste to obtain cheap products in demand.","PeriodicalId":14640,"journal":{"name":"IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87372809","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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