V. Tarabanko, I. Simakova, M. Smirnova, K. L. Kaygorodov
The process of catalytic hydrogenation of furfural diethyl acetal to ethyl furfuryl ether on the different catalysts (palladium, palladium-rhenium and copper-ruthenium on Sibunit in reduced forms) was studied. It was found that hydrogenation of the furan ring with the formation of THF diethyl acetal occurs on all the catalysts. Ethyl furfuryl ether becomes the main product while carrying on the second hydrogenation cycle on spent palladium catalyst (yield and selectivity up to 55 % and 85 %, respectively)
{"title":"Catalytic Hydrogenation of Furfural Diethyl Acetal to Ethyl Furfuryl Ether","authors":"V. Tarabanko, I. Simakova, M. Smirnova, K. L. Kaygorodov","doi":"10.17516/1998-2836-0237","DOIUrl":"https://doi.org/10.17516/1998-2836-0237","url":null,"abstract":"The process of catalytic hydrogenation of furfural diethyl acetal to ethyl furfuryl ether on the different catalysts (palladium, palladium-rhenium and copper-ruthenium on Sibunit in reduced forms) was studied. It was found that hydrogenation of the furan ring with the formation of THF diethyl acetal occurs on all the catalysts. Ethyl furfuryl ether becomes the main product while carrying on the second hydrogenation cycle on spent palladium catalyst (yield and selectivity up to 55 % and 85 %, respectively)","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"220 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80045657","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}
V. A. Ionin, A. Kazachenko, A. M. Skripnikov, E. V. Veprikova, M. Belash, O. Taran
The optimization of the process of β-sitosterol extraction from the original and activated with two different methods (drum mill, explosive autohydrolysis) pine bark was carried out. The effect of the duration of the extraction process and the concentration of NaOH in the saponification solution on the yield of β-sitosterol was explored. The concentration of NaOH in the saponification solution appeared to have the highest effect on the β-sitosterol yields from activated pine bark. Mechanical activation of pine bark significantly increased the yield of β-sitosterol and reduced the duration of the isolation process. The highest yield of β-sitosterol was achieved with the use of pine bark activated by explosive autohydrolysis. According to the proposed mathematical model, the maximum predicted value of the β-sitosterol yield from this sample is 0.078 (wt%). This could be achieved using the process duration 10.3 hours and a 0.5 N solution of NaOH. This yield is close to the content of β-sitosterol in the original pine bark
{"title":"Experimental and Mathematical Optimization of the β-Sitosterol extraction from Mechanically Activated Pine Bark","authors":"V. A. Ionin, A. Kazachenko, A. M. Skripnikov, E. V. Veprikova, M. Belash, O. Taran","doi":"10.17516/1998-2836-0248","DOIUrl":"https://doi.org/10.17516/1998-2836-0248","url":null,"abstract":"The optimization of the process of β-sitosterol extraction from the original and activated with two different methods (drum mill, explosive autohydrolysis) pine bark was carried out. The effect of the duration of the extraction process and the concentration of NaOH in the saponification solution on the yield of β-sitosterol was explored. The concentration of NaOH in the saponification solution appeared to have the highest effect on the β-sitosterol yields from activated pine bark. Mechanical activation of pine bark significantly increased the yield of β-sitosterol and reduced the duration of the isolation process. The highest yield of β-sitosterol was achieved with the use of pine bark activated by explosive autohydrolysis. According to the proposed mathematical model, the maximum predicted value of the β-sitosterol yield from this sample is 0.078 (wt%). This could be achieved using the process duration 10.3 hours and a 0.5 N solution of NaOH. This yield is close to the content of β-sitosterol in the original pine bark","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"4 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84502763","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}
Successful search for optimal molecular structures of membrane materials requires efficient algorithms for assessing their diffusion properties. It is shown in this work that the potential landscape of a probe penetrating particle, a component that passes through the membrane during gas separation, is suitable for solving such problems. A number of indicators are considered that can be easily calculated from potential landscapes of specific models of silicate materials, both not related to the topology of the potential landscape (global minimum, voxel energy distribution), and depending on it (percolation cluster). A good correlation of these indicators with the corresponding diffusion coefficients is shown
{"title":"Potential Landscape of a Probe Penetrant Particle for Fast Estimating of Silica Diffusion Properties","authors":"Sergey V. Kukhtetskiy","doi":"10.17516/1998-2836-0250","DOIUrl":"https://doi.org/10.17516/1998-2836-0250","url":null,"abstract":"Successful search for optimal molecular structures of membrane materials requires efficient algorithms for assessing their diffusion properties. It is shown in this work that the potential landscape of a probe penetrating particle, a component that passes through the membrane during gas separation, is suitable for solving such problems. A number of indicators are considered that can be easily calculated from potential landscapes of specific models of silicate materials, both not related to the topology of the potential landscape (global minimum, voxel energy distribution), and depending on it (percolation cluster). A good correlation of these indicators with the corresponding diffusion coefficients is shown","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"71 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84719736","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}
V. Levdansky, A. Kondrasenko, A. Levdansky, B. Kuznetsov
Sulfation of birch wood xylan in 1,4-dioxane by sulfamic acid in the presence of urea at 90 and 100 °C was studied for the first time. The effect of the duration of xylan sulfation on the yield of xylan sulfates and the sulfur content in them was studied. It was found that the sulfur content in the obtained xylan sulfates increases from 12.5 to 17.5 wt% with an increase in the duration of sulfation from 2 to 4 hours. The structure of initial and sulfated xylan was studied by FTIR and NMR spectroscopy. The ease of purification of the obtained xylan sulfates from 1,4-dioxane in comparison with the purification of xylan sulfates obtained by sulfation in pyridine and N, N‑dimethylformamide is an advantage of the proposed method of xylan sulfation
首次研究了在尿素存在下，磺胺酸在90℃和100℃下对1,4-二恶烷中桦木木聚糖的磺化反应。研究了木聚糖磺化时间对木聚糖硫酸盐收率和硫酸盐中硫含量的影响。结果表明，随着硫化时间从2小时增加到4小时，得到的木聚糖硫酸盐中硫含量从12.5 wt%增加到17.5%。用傅立叶变换红外光谱(FTIR)和核磁共振光谱(NMR)研究了初始木聚糖和磺化木聚糖的结构。与在吡啶和N, N -二甲基甲酰胺中磺化得到的木聚糖硫酸盐相比，从1,4-二氧六环中得到的木聚糖硫酸盐易于纯化，这是木聚糖磺化方法的一个优点
{"title":"Sylfation of Birch Wood Xylan with Sulfamic Acid in 1,4-dioxane","authors":"V. Levdansky, A. Kondrasenko, A. Levdansky, B. Kuznetsov","doi":"10.17516/1998-2836-0241","DOIUrl":"https://doi.org/10.17516/1998-2836-0241","url":null,"abstract":"Sulfation of birch wood xylan in 1,4-dioxane by sulfamic acid in the presence of urea at 90 and 100 °C was studied for the first time. The effect of the duration of xylan sulfation on the yield of xylan sulfates and the sulfur content in them was studied. It was found that the sulfur content in the obtained xylan sulfates increases from 12.5 to 17.5 wt% with an increase in the duration of sulfation from 2 to 4 hours. The structure of initial and sulfated xylan was studied by FTIR and NMR spectroscopy. The ease of purification of the obtained xylan sulfates from 1,4-dioxane in comparison with the purification of xylan sulfates obtained by sulfation in pyridine and N, N‑dimethylformamide is an advantage of the proposed method of xylan sulfation","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"36 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89734765","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}
Catalysts for upgrading of the straight-run gasoline fraction of oil were prepared on the basis of a ZSM‑5 zeolite via dry mechanical mixing with an ultrafine rhenium powder. It was shown how the structural and acidic characteristics of zeolite ZSM‑5 changed when it was modified with rhenium. The concentration and nature of carbon condensation products formed on the prepared catalysts during the processing of straight--run gasoline have been determined. An enhancement of operating efficiency of rhenium--containing zeolite catalysts in comparison with an unmodified zeolite was established, which consisted in increasing their capacity and reducing the rate of deactivation in the process under study
{"title":"Physicochemical and Catalytic Properties of Rhenium-Containing Zeolites in the Course of Straight-Run Gasoline Upgrading","authors":"L. Velichkina","doi":"10.17516/1998-2836-0247","DOIUrl":"https://doi.org/10.17516/1998-2836-0247","url":null,"abstract":"Catalysts for upgrading of the straight-run gasoline fraction of oil were prepared on the basis of a ZSM‑5 zeolite via dry mechanical mixing with an ultrafine rhenium powder. It was shown how the structural and acidic characteristics of zeolite ZSM‑5 changed when it was modified with rhenium. The concentration and nature of carbon condensation products formed on the prepared catalysts during the processing of straight--run gasoline have been determined. An enhancement of operating efficiency of rhenium--containing zeolite catalysts in comparison with an unmodified zeolite was established, which consisted in increasing their capacity and reducing the rate of deactivation in the process under study","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"34 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88508819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Saikova, D. I. Chistyakov, D. Saykova, Y. Mikhlin, D. Kuzmin
We examined the interaction of aqueous solutions of lead nitrate and sodium dibutyl dithiophosphate and showed the formation nanoparticles of lead dibutyl dithiophosphate. The effect of reaction parameters on the synthesis of nanoparticles was studied and the optimal conditions for the formation of their stable hydrosols were determined. The obtained products were investigated by methods of optical spectroscopy, dynamic light scattering. The average size of 15–20 nm, but due to the low surface charge, they are combined into larger aggregates. The UV‑vis spectra has absorption maximum at about 320 nm. TEM micrographs and Pb 2p, S2p XAS spectra revealed a composition and structure of the particles. These nanoparticles can play an important role in the flotation of sulfide minerals of nonferrous metals
{"title":"Synthesis and Characterization of Lead Dibutyl Dithiophosphate Nanoparticles","authors":"S. Saikova, D. I. Chistyakov, D. Saykova, Y. Mikhlin, D. Kuzmin","doi":"10.17516/1998-2836-0243","DOIUrl":"https://doi.org/10.17516/1998-2836-0243","url":null,"abstract":"We examined the interaction of aqueous solutions of lead nitrate and sodium dibutyl dithiophosphate and showed the formation nanoparticles of lead dibutyl dithiophosphate. The effect of reaction parameters on the synthesis of nanoparticles was studied and the optimal conditions for the formation of their stable hydrosols were determined. The obtained products were investigated by methods of optical spectroscopy, dynamic light scattering. The average size of 15–20 nm, but due to the low surface charge, they are combined into larger aggregates. The UV‑vis spectra has absorption maximum at about 320 nm. TEM micrographs and Pb 2p, S2p XAS spectra revealed a composition and structure of the particles. These nanoparticles can play an important role in the flotation of sulfide minerals of nonferrous metals","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"70 2","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72430634","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}
Silicas, sequentially modified with polyhexamethylene guanidine and 8-hydroxyquinoline‑5-sulfonic acid (SiO2-PHMG‑oxine) or 7-iodine‑8-hydroxyquinoline‑5-sulfonic acid (SiO2-PHMG‑ferron), have been proposed for the adsorption-luminescent determination of Y(III) in natural waters. Complex compounds of Y(III) are formed on the surface of adsorbents during adsorption from solutions at pH 6–7, which luminesce in a yellow-green color (λlum = 485 nm (SiO2-PHMG‑oxine) and λlum = 490 nm (SiO2-PHMG‑ferron)). This is the basis for the method of its sorption-luminescent determination. The detection limit of Y(III), calculated according to the 3s criterion, is 1 μg/L (SiO2-PHMG‑oxine) and 2 μg/L (SiO2-PHMG‑ferron), the analytical range is 4–400 μg/L (SiO2-PHMG‑oxine) and 6–500 μg/L (SiO2-PHMG‑ferron). The developed methods were tested in the determination of yttrium in the Yenisei and Kacha rivers of the Krasnoyarsk Krai
{"title":"Adsorption-Luminescent Determination of Y(III) Using 8-oxyquinoline Derivatives Fixed on the Silica Surface","authors":"O. Buyko, V. Losev, A. F. Shimanskii","doi":"10.17516/1998-2836-0242","DOIUrl":"https://doi.org/10.17516/1998-2836-0242","url":null,"abstract":"Silicas, sequentially modified with polyhexamethylene guanidine and 8-hydroxyquinoline‑5-sulfonic acid (SiO2-PHMG‑oxine) or 7-iodine‑8-hydroxyquinoline‑5-sulfonic acid (SiO2-PHMG‑ferron), have been proposed for the adsorption-luminescent determination of Y(III) in natural waters. Complex compounds of Y(III) are formed on the surface of adsorbents during adsorption from solutions at pH 6–7, which luminesce in a yellow-green color (λlum = 485 nm (SiO2-PHMG‑oxine) and λlum = 490 nm (SiO2-PHMG‑ferron)). This is the basis for the method of its sorption-luminescent determination. The detection limit of Y(III), calculated according to the 3s criterion, is 1 μg/L (SiO2-PHMG‑oxine) and 2 μg/L (SiO2-PHMG‑ferron), the analytical range is 4–400 μg/L (SiO2-PHMG‑oxine) and 6–500 μg/L (SiO2-PHMG‑ferron). The developed methods were tested in the determination of yttrium in the Yenisei and Kacha rivers of the Krasnoyarsk Krai","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"40 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75733121","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}
Effect of the concentration of surfactants differing in nature on the inhibition of the growth of microorganisms of the genus Pseudomonas putida was studied. All the surfactants inhibited the metabolic growth of microorganisms to various degrees. The results depended on the nature of the surfactants. For each surfactant, there is a range of concentrations characteristic of the growth or suppression of the growth of microorganisms. The values of the minimum inhibitory concentration and the growth inhibition zones diameters of the surfactants are compared. The highest antimicrobial activity belonged to the cationic Dimethylaminopropyl stearamide in relation to Pseudomonas putida
{"title":"Concentration Dependence of Antimicrobial Properties of Various Surfactants Against Bacteria Pseudomonas putida","authors":"A. S. Burlachenko, O. Salishcheva","doi":"10.17516/1998-2836-0229","DOIUrl":"https://doi.org/10.17516/1998-2836-0229","url":null,"abstract":"Effect of the concentration of surfactants differing in nature on the inhibition of the growth of microorganisms of the genus Pseudomonas putida was studied. All the surfactants inhibited the metabolic growth of microorganisms to various degrees. The results depended on the nature of the surfactants. For each surfactant, there is a range of concentrations characteristic of the growth or suppression of the growth of microorganisms. The values of the minimum inhibitory concentration and the growth inhibition zones diameters of the surfactants are compared. The highest antimicrobial activity belonged to the cationic Dimethylaminopropyl stearamide in relation to Pseudomonas putida","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"7 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79310429","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}
V. Bondaletov, Liudmila I. Bondaletova, Van Thanh Nguyen, A. V. Bondaletova
It was advised to use aliphatic, cycloaliphatic, aromatic petroleum resins and their derivatives obtained by oxidation of resins with a mixture of hydrogen peroxide and acetic acid as bitumen polymer-modifiers. Petroleum resins were obtained by ionic polymerization of unsaturated compounds of liquid pyrolysis products under the influence of titanium tetrachloride-diethylaluminium chloride catalyst. It was established that the maximum values of adhesion of modified bitumen coatings to metal substrates, corresponding to the minimum values of the wetting angle of the metal surface coated with solutions of bitumen compositions with different content of the polymer modifier were achieved using oxidized resins. All modified bitumen coatings have low water absorptivity and high acid resistance, alkali resistance and salt resistance, which allow using them as protective coatings
{"title":"Properties of Bitumen Composition Modified by Petroleum Resins","authors":"V. Bondaletov, Liudmila I. Bondaletova, Van Thanh Nguyen, A. V. Bondaletova","doi":"10.17516/1998-2836-0224","DOIUrl":"https://doi.org/10.17516/1998-2836-0224","url":null,"abstract":"It was advised to use aliphatic, cycloaliphatic, aromatic petroleum resins and their derivatives obtained by oxidation of resins with a mixture of hydrogen peroxide and acetic acid as bitumen polymer-modifiers. Petroleum resins were obtained by ionic polymerization of unsaturated compounds of liquid pyrolysis products under the influence of titanium tetrachloride-diethylaluminium chloride catalyst. It was established that the maximum values of adhesion of modified bitumen coatings to metal substrates, corresponding to the minimum values of the wetting angle of the metal surface coated with solutions of bitumen compositions with different content of the polymer modifier were achieved using oxidized resins. All modified bitumen coatings have low water absorptivity and high acid resistance, alkali resistance and salt resistance, which allow using them as protective coatings","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"39 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86190449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study cracking of a mixture of mechanically activated oil shale (MO OSh) and fuel oil, a mixture of demineralized MO GS and fuel oil has been investigated. The data on the composition of liquid products showed that after the removal of mineral components, oil shale is more easily destroyed due to the release of kerogen. It is shown that in the obtained liquid products of the cracking of the mixture of fuel oil – demineralized MO OSh, the proportion of oils increases to 74.6 % wt. In the composition of gaseous products of cracking, the amount of hydrogen, methane and ethane is noticeably reduced. According to the data on the fractional composition of liquid products, it was found that during the cracking of mixtures of fuel oil and MO HS, after the removal of carbonates and silicates, the proportion of gasoline and diesel fractions inc
{"title":"The Effect of Carbonates and Silicates on the Cracking of a Mixture of Fuel Oil and Mechanically Activated Oil Shale","authors":"M. V. Mozhayskaya, G. Pevneva, V. G. Surkov","doi":"10.17516/1998-2836-0232","DOIUrl":"https://doi.org/10.17516/1998-2836-0232","url":null,"abstract":"The study cracking of a mixture of mechanically activated oil shale (MO OSh) and fuel oil, a mixture of demineralized MO GS and fuel oil has been investigated. The data on the composition of liquid products showed that after the removal of mineral components, oil shale is more easily destroyed due to the release of kerogen. It is shown that in the obtained liquid products of the cracking of the mixture of fuel oil – demineralized MO OSh, the proportion of oils increases to 74.6 % wt. In the composition of gaseous products of cracking, the amount of hydrogen, methane and ethane is noticeably reduced. According to the data on the fractional composition of liquid products, it was found that during the cracking of mixtures of fuel oil and MO HS, after the removal of carbonates and silicates, the proportion of gasoline and diesel fractions inc","PeriodicalId":16999,"journal":{"name":"Journal of Siberian Federal University. Chemistry","volume":"19 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84412544","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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