Salicylaldehyde Schiff base-Cu complex (1:1 [M:L] chelate) was synthesized using salicylaldehyde, urea, and CuCl2. Its catalytic activity was then assessed in N-arylation of aromatic amines (1H-indole, 1H- pyrazole, 1H-imidazole, 1H-benzo[d][1,2,3]triazole, and aniline) with aryl halides. This reaction does not need aryl boronic acids as the active aryl source or palladium-based catalyst. Cu is cheaper than many other catalysts, and required ligands usually having quite simple structure and being inexpensive. On the other hand, with a proper ligand selection we can have a modified solubility, reactivity, and reaction efficiency. The structure and composition of this novel complex were approved by FT-IR, UV-Vis, atomic absorption spectroscopy, elemental analysis, and TGA/DTA. Investigating the antibacterial activity of the Cu complex suggests a significant antibacterial activity against standard species Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis.
{"title":"Synthesis and Antimicrobial Activities of Salicylaldehyde Schiff Base-Cu(II) Complex and Its Catalytic Activity in N-Arylation Reactions","authors":"Afrooz Majdi-Nasab, Fariba Heidarizadeh, Hossein Motamedi","doi":"10.23939/chcht17.03.557","DOIUrl":"https://doi.org/10.23939/chcht17.03.557","url":null,"abstract":"Salicylaldehyde Schiff base-Cu complex (1:1 [M:L] chelate) was synthesized using salicylaldehyde, urea, and CuCl2. Its catalytic activity was then assessed in N-arylation of aromatic amines (1H-indole, 1H- pyrazole, 1H-imidazole, 1H-benzo[d][1,2,3]triazole, and aniline) with aryl halides. This reaction does not need aryl boronic acids as the active aryl source or palladium-based catalyst. Cu is cheaper than many other catalysts, and required ligands usually having quite simple structure and being inexpensive. On the other hand, with a proper ligand selection we can have a modified solubility, reactivity, and reaction efficiency. The structure and composition of this novel complex were approved by FT-IR, UV-Vis, atomic absorption spectroscopy, elemental analysis, and TGA/DTA. Investigating the antibacterial activity of the Cu complex suggests a significant antibacterial activity against standard species Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135008715","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 activity of the photoinitiator system, based on triethanolamine (TEOA) and methylene blue (MB), on the photopolymerization of hydroxyethyl acrylate (HEA) monomer under very soft irradiation conditions, was evaluated. A remarkable difference in the polymerization kinetics of a set of PHEA experiments was underlined according to TEOA/MB concentrations, as well as the solutions pH. Indeed, the complex viscosity (η*), storage modulus (G'), and loss modulus (G") of the resulting polymers were potentially dependent on these experimental parameters despite comparable values of monomer conversion.
{"title":"Photopolymerization of Poly(Hydroxyethyl Acrylate) (PHEA): Experimental Parameters-Viscoelastic Properties Relationship","authors":"Nouria Bouchikhi, Djahida Lerari, Salah Hamri, Faycal Dergal, Khaldoun Bachari, Lamia Bedjaoui-Alachaher","doi":"10.23939/chcht17.03.592","DOIUrl":"https://doi.org/10.23939/chcht17.03.592","url":null,"abstract":"The activity of the photoinitiator system, based on triethanolamine (TEOA) and methylene blue (MB), on the photopolymerization of hydroxyethyl acrylate (HEA) monomer under very soft irradiation conditions, was evaluated. A remarkable difference in the polymerization kinetics of a set of PHEA experiments was underlined according to TEOA/MB concentrations, as well as the solutions pH. Indeed, the complex viscosity (η*), storage modulus (G'), and loss modulus (G\") of the resulting polymers were potentially dependent on these experimental parameters despite comparable values of monomer conversion.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135008716","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}
Khaoula Kouchkar, Youcef Boumedjane, Salah Eddine Hachani
In this scientific contribution, regio- and diastereo- selectivity of [3+2] cycloaddition (32CA) of N-tert-butyl,α-(4-trifluoromethyl)-phenylnitrone (1) with methacrolein (2) were investigated using DFT method at B3LYP/6-31(d) computational level in gas and dichloromethane solvent. The molecular electrostatic potential MESP was used to show the most active centers in the examined molecules. Global and local reactivity indices as well as thermodynamic parameters have been calculated to explain the regioselectivity and stereoselectivity for the selected reaction. The possible chemoselective ortho/meta regioselectivity and stereo- (endo/exo) isomeric channels were investigated. Our theoretical results give important elucidations for the possible pathways related to the studied 32CA reaction.
{"title":"[3+2] Cycloaddition of N-tert-Butyl, -(4-Trifluoromethyl)-Phenylnitrone with Methacrolein: Theoretical Investigation","authors":"Khaoula Kouchkar, Youcef Boumedjane, Salah Eddine Hachani","doi":"10.23939/chcht17.03.518","DOIUrl":"https://doi.org/10.23939/chcht17.03.518","url":null,"abstract":"In this scientific contribution, regio- and diastereo- selectivity of [3+2] cycloaddition (32CA) of N-tert-butyl,α-(4-trifluoromethyl)-phenylnitrone (1) with methacrolein (2) were investigated using DFT method at B3LYP/6-31(d) computational level in gas and dichloromethane solvent. The molecular electrostatic potential MESP was used to show the most active centers in the examined molecules. Global and local reactivity indices as well as thermodynamic parameters have been calculated to explain the regioselectivity and stereoselectivity for the selected reaction. The possible chemoselective ortho/meta regioselectivity and stereo- (endo/exo) isomeric channels were investigated. Our theoretical results give important elucidations for the possible pathways related to the studied 32CA reaction.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010646","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 simulated heat transfer in alumina-water nanofluid in a natural convection flow and Rayleigh-Benard configuration considering the Brownian motions and fractal structure of the nanofluids. The simulations were based on a two-dimensional, Eulerian-Eulerian method. Many simulations have been performed to examine the effect of aspect ratio, heat flux, and para-meters related to the structure of the nanoclusters including size, fractal dimension, and volume fraction on the natural convective heat transfer coefficient. The comparison between the simulation results and the experimental data of heat transfer coefficient indicates a good agreement. The simulation results indicated that the enhancement of aspect ratio, heat flux, and fractal dimension increases the heat transfer coefficient. On the other hand, the reduction of nanoclusters and nanoparticle size decreased this coefficient. Moreover, the simulation results showed that in high heat transfer fluxes, the heat transfer coefficient first increases by increasing the nanoparticles solid volume fraction and then decreases. However, heat transfer coefficient decreased steadily with the increase in the nanoparticles solid volume fraction in low heat transfer fluxes. The results suggested that using the nanoparticles Brownian motion mechanism along with their fractal structure can be well-applied in natural-convection heat transfer modelling of nanofluids.
{"title":"Effects of Brownian Motions and Fractal Structure of Nanoparticles on Natural Convection","authors":"Zohreh Zobeidi, Roohollah Sadeghi, Mohamad-Taghi Rostami","doi":"10.23939/chcht17.03.617","DOIUrl":"https://doi.org/10.23939/chcht17.03.617","url":null,"abstract":"The study simulated heat transfer in alumina-water nanofluid in a natural convection flow and Rayleigh-Benard configuration considering the Brownian motions and fractal structure of the nanofluids. The simulations were based on a two-dimensional, Eulerian-Eulerian method. Many simulations have been performed to examine the effect of aspect ratio, heat flux, and para-meters related to the structure of the nanoclusters including size, fractal dimension, and volume fraction on the natural convective heat transfer coefficient. The comparison between the simulation results and the experimental data of heat transfer coefficient indicates a good agreement. The simulation results indicated that the enhancement of aspect ratio, heat flux, and fractal dimension increases the heat transfer coefficient. On the other hand, the reduction of nanoclusters and nanoparticle size decreased this coefficient. Moreover, the simulation results showed that in high heat transfer fluxes, the heat transfer coefficient first increases by increasing the nanoparticles solid volume fraction and then decreases. However, heat transfer coefficient decreased steadily with the increase in the nanoparticles solid volume fraction in low heat transfer fluxes. The results suggested that using the nanoparticles Brownian motion mechanism along with their fractal structure can be well-applied in natural-convection heat transfer modelling of nanofluids.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135008709","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}
This study compares the classic calculating method of the heat transfer coefficients of the shell-and-tube heat exchanger tubes using the classic Nusselt, Reynolds, and Prandtl similarity numbers with a new method that takes into account the coefficients of surface tension of heat carriers, their transitional, turbulent viscosity and thermal conductivity, as well as the average thickness of the laminar boundary layer (LBL). The classic method shows a better efficiency of water as a heat carrier com-pared to a 45% aqueous solution of propylene glycol. Instead, the new calculation method shows that a 45% aqueous solution of propylene glycol at the same Rey-nolds numbers has higher heat transfer coefficients com-pared to water in the temperature range of 273–353 K. We divided the "live cross-section" of the flow of the liquid coolant into a medium-thick LBL, where the Fourier equation of thermal conductivity is applied, and into its turbulent part, where the equation of thermal conductivity with turbulent thermal conductivity is also applied. A new formula (14) is proposed for calculating the average thickness of the LBL based on the radius of the "live cross-section" of the coolant flow, as well as the Blturb similarity number obtained by us in previous works. A new formula (15) is also proposed for calculating the heat transfer coefficient, which includes the transitional and turbulent thermal conductivity of the corresponding zones of the flow "live section", as well as the average thickness of the LBL.
{"title":"Improvement of the Method of Calculating Heat Transfer Coefficients Using Glycols Taking into Account Surface Forces of Heat Carriers","authors":"Yuriy Bilonoga, Volodymyr Atamanyuk, Volodymyr Stybel, Ihor Dutsyak, Uliana Drachuk","doi":"10.23939/chcht17.03.608","DOIUrl":"https://doi.org/10.23939/chcht17.03.608","url":null,"abstract":"This study compares the classic calculating method of the heat transfer coefficients of the shell-and-tube heat exchanger tubes using the classic Nusselt, Reynolds, and Prandtl similarity numbers with a new method that takes into account the coefficients of surface tension of heat carriers, their transitional, turbulent viscosity and thermal conductivity, as well as the average thickness of the laminar boundary layer (LBL). The classic method shows a better efficiency of water as a heat carrier com-pared to a 45% aqueous solution of propylene glycol. Instead, the new calculation method shows that a 45% aqueous solution of propylene glycol at the same Rey-nolds numbers has higher heat transfer coefficients com-pared to water in the temperature range of 273–353 K. We divided the \"live cross-section\" of the flow of the liquid coolant into a medium-thick LBL, where the Fourier equation of thermal conductivity is applied, and into its turbulent part, where the equation of thermal conductivity with turbulent thermal conductivity is also applied. A new formula (14) is proposed for calculating the average thickness of the LBL based on the radius of the \"live cross-section\" of the coolant flow, as well as the Blturb similarity number obtained by us in previous works. A new formula (15) is also proposed for calculating the heat transfer coefficient, which includes the transitional and turbulent thermal conductivity of the corresponding zones of the flow \"live section\", as well as the average thickness of the LBL.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010643","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}
A series of salicylaldehydes have been prepared through the replacement of the easily leaving chlorine atom in 5-chloromethyl-2-hydroxybenzaldehyde with various O-, S- or N-nucleophiles. The involvement of a few of these salicylaldehydes in the synthesis of heterocycles such as benzofuran or coumarin, or as substrate in the Petasis borono-Mannich reaction has been explored.
{"title":"Salicylaldehydes Derived from 5-Chloromethyl-2-hydroxybenzaldehyde – Synthesis and Reactions","authors":"Gheorghe Roman","doi":"10.23939/chcht17.03.532","DOIUrl":"https://doi.org/10.23939/chcht17.03.532","url":null,"abstract":"A series of salicylaldehydes have been prepared through the replacement of the easily leaving chlorine atom in 5-chloromethyl-2-hydroxybenzaldehyde with various O-, S- or N-nucleophiles. The involvement of a few of these salicylaldehydes in the synthesis of heterocycles such as benzofuran or coumarin, or as substrate in the Petasis borono-Mannich reaction has been explored.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010651","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}
In this study, MgAl2O4 nanoparticles with different calcination times were synthesized for photocatalytic applications. Different analyses techniques such as XRD, SEM, EDX, UV-visible, and FTIR were performed to investigate the structural, chemical, optical, and mor-phological properties of the synthesized nanoparticles. XRD analysis revealed the formation MgAl2O4 spinel structure. UV-Visible measurements indicate that MgAl2O4-2 nanoparticles had a narrower energy gap compared to MgAl2O4-1 and MgAl2O4-3. Results of SEM analysis revealed that the synthesized MgAl2O4 nanoparticles consist of small aggregated particles with (40-60 nm) particles size. EDX measurements con-firmed the formation of MgAl2O4 nanoparticles without any impurities. The photocatalytic performance was evaluated by the photodegradation of polyethylene plastics using MgAl2O4 nanoparticles under UV irradiation. The FT-IR measurements before and after the degradation of polyethylene plastics confirm the formation of new functional groups as a result of photodegradation processes.
{"title":"Photocatalytic Degradation of Polyethylene Plastics Using MgAl2O4 Nanoparticles Prepared by Solid State Method","authors":"Sajda .S. Affat, Saad Shahad Mohammed","doi":"10.23939/chcht17.03.503","DOIUrl":"https://doi.org/10.23939/chcht17.03.503","url":null,"abstract":"In this study, MgAl2O4 nanoparticles with different calcination times were synthesized for photocatalytic applications. Different analyses techniques such as XRD, SEM, EDX, UV-visible, and FTIR were performed to investigate the structural, chemical, optical, and mor-phological properties of the synthesized nanoparticles. XRD analysis revealed the formation MgAl2O4 spinel structure. UV-Visible measurements indicate that MgAl2O4-2 nanoparticles had a narrower energy gap compared to MgAl2O4-1 and MgAl2O4-3. Results of SEM analysis revealed that the synthesized MgAl2O4 nanoparticles consist of small aggregated particles with (40-60 nm) particles size. EDX measurements con-firmed the formation of MgAl2O4 nanoparticles without any impurities. The photocatalytic performance was evaluated by the photodegradation of polyethylene plastics using MgAl2O4 nanoparticles under UV irradiation. The FT-IR measurements before and after the degradation of polyethylene plastics confirm the formation of new functional groups as a result of photodegradation processes.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135008706","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}
Oksana Savvova, Yana Pokroieva, Hennadii Voronov, Olena Babich, Yuliia Smyrnova
Antibacterial satin glass-ceramic coatings for ceramic tiles have been developed by one-stage firing on the basis of high-calcium zinc aluminum silicate frits, which are modified with heavy metal cations. The antibacterial effect of the developed matte glass-ceramic coatings with a satin texture was established due to the effect of potentiating the antibacterial activity of the combined action of the hardystonite crystalline phase and fillers of zinc and tin oxides.
{"title":"Antibacterial Matte Glass-Ceramic Coatings with Satin Texture for Ceramic Tiles","authors":"Oksana Savvova, Yana Pokroieva, Hennadii Voronov, Olena Babich, Yuliia Smyrnova","doi":"10.23939/chcht17.03.655","DOIUrl":"https://doi.org/10.23939/chcht17.03.655","url":null,"abstract":"Antibacterial satin glass-ceramic coatings for ceramic tiles have been developed by one-stage firing on the basis of high-calcium zinc aluminum silicate frits, which are modified with heavy metal cations. The antibacterial effect of the developed matte glass-ceramic coatings with a satin texture was established due to the effect of potentiating the antibacterial activity of the combined action of the hardystonite crystalline phase and fillers of zinc and tin oxides.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135008710","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}
Areas of use of natural clinoptilolite were analyzed. The emphasis was placed on its application in water technology and medical practice. The results of the study of the dehydration of clinoptilolite at different temperatures were presented. The influence of the activation temperature of clinoptilolite on its sorption capacity for silver ions was determined. The effect of modification with ions and highly dispersed silver particles on the sorption capacity of various zeolite fractions with respect to water was investigated.
{"title":"Influence of Natural Clinoptilolite Modification with Ions and Zero-Valent Silver on Its Sorption Capacity","authors":"Zenovii Znak, Viktoria Kochubei","doi":"10.23939/chcht17.03.646","DOIUrl":"https://doi.org/10.23939/chcht17.03.646","url":null,"abstract":"Areas of use of natural clinoptilolite were analyzed. The emphasis was placed on its application in water technology and medical practice. The results of the study of the dehydration of clinoptilolite at different temperatures were presented. The influence of the activation temperature of clinoptilolite on its sorption capacity for silver ions was determined. The effect of modification with ions and highly dispersed silver particles on the sorption capacity of various zeolite fractions with respect to water was investigated.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010640","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}
G-quadruplex DNA is formed in telomer. It inhibits telomerase enzyme which is found active in more than 85 % of cancer cells. In this work, the effect of Tween 80 on telomeric G-quadruplex DNA, AGGG(TTAGGG)3 was studied using circular dichroism spectroscopic technique. The obtained results showed that using Tween 80 with telomeric quadruplex is safe up to less than 1.0 %.
g -四重体DNA在端粒体中形成。它能抑制端粒酶，这种酶在85%以上的癌细胞中都很活跃。本文利用圆二色光谱技术研究了Tween 80对端粒g -四重体DNA AGGG(TTAGGG)3的影响。结果表明，端粒四重体使用Tween 80的安全性不超过1.0%。
{"title":"Effect of Tween 80 on the Stability and Conformation of Telomeric G-Quadruplex DNA","authors":"Ismail A. Elhaty","doi":"10.23939/chcht17.03.567","DOIUrl":"https://doi.org/10.23939/chcht17.03.567","url":null,"abstract":"G-quadruplex DNA is formed in telomer. It inhibits telomerase enzyme which is found active in more than 85 % of cancer cells. In this work, the effect of Tween 80 on telomeric G-quadruplex DNA, AGGG(TTAGGG)3 was studied using circular dichroism spectroscopic technique. The obtained results showed that using Tween 80 with telomeric quadruplex is safe up to less than 1.0 %.","PeriodicalId":9762,"journal":{"name":"Chemistry and Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135010647","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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