This article provided a research for the trend of heat transfer and flow field through a 2-dimensional wavy duct. To construct a grid mesh, the physical domain was transferred to the computational domain and finite volume scheme was used for discretizing the governing equations. Through the simulation, the flow regime stayed in laminar mode. Constant temperature boundary condition has been used for solid walls. Air was used as a working fluid. Existence of waves makes some phenomenon like flow separation. Effect of Reynolds number, wave width, and wave number has been analyzed and velocity distribution, heat transfer coefficient, and tangential stress were computed for different cases. The final results were compared with the same straight duct. The entropy generation minimization method has been used for better comparison between final results.
{"title":"Numerical Analysis of Flow Field and Heat Transfer of 2D Wavy Ducts and Optimization by Entropy Generation Minimization Method","authors":"O. N. Zonouz, M. Salmanpour","doi":"10.1155/2012/574596","DOIUrl":"https://doi.org/10.1155/2012/574596","url":null,"abstract":"This article provided a research for the trend of heat transfer and flow field through a 2-dimensional wavy duct. To construct a grid mesh, the physical domain was transferred to the computational domain and finite volume scheme was used for discretizing the governing equations. Through the simulation, the flow regime stayed in laminar mode. Constant temperature boundary condition has been used for solid walls. Air was used as a working fluid. Existence of waves makes some phenomenon like flow separation. Effect of Reynolds number, wave width, and wave number has been analyzed and velocity distribution, heat transfer coefficient, and tangential stress were computed for different cases. The final results were compared with the same straight duct. The entropy generation minimization method has been used for better comparison between final results.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76209188","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}
Y. Yoshimura, N. Hatano, Y. Imai, H. Abe, Osamu Shimada, T. Hanasaki
By a simple differential thermal analysis (DTA) system, the concentration dependence of the glass transition temperatures (𝑇𝑔s) for the quaternary ammonium-type ionic liquid, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bromide [DEME][Br] and H2O mixtures, after quick precooling was measured as a function of water concentration 𝑥 (mol% H2O). We compared the results with the previous results of [DEME][I]-H2O and [DEME][BF4]-H2O mixtures in which a double-glass transition behavior was observed. Remarkably, the [DEME][Br]-H2O mixtures basically show one-𝑇𝑔 behavior and the 𝑇𝑔 decreases monotonically with increasing H2O content up to around 𝑥=91.5. But it suddenly jumps to higher 𝑇𝑔 value at a specific 𝑥=∼92. At this very limited point, two 𝑇𝑔s (𝑇𝑔1,𝑇𝑔2) which we might consider as a transition state from the structure belonging to the 𝑇𝑔1 group to another one due to the 𝑇𝑔2 group were observed. These results clearly reflect the difference in the anionic effects among Br−, I−, and BF4−. The end of the glass-formation region of [DEME][Br]-H2O mixtures is around 𝑥=98.9 and moves to more water-rich region as compared to those of [DEME][BF4]-H2O (𝑥=96.0) and [DEME][I]-H2O (𝑥=95.0) mixtures.
{"title":"Glass Transition Behavior of the Quaternary Ammonium-Type Ionic Liquid: N,N-Diethyl-N-methyl-N-(2-methoxyethyl)ammonium Bromide-H2O Mixtures","authors":"Y. Yoshimura, N. Hatano, Y. Imai, H. Abe, Osamu Shimada, T. Hanasaki","doi":"10.1155/2012/575728","DOIUrl":"https://doi.org/10.1155/2012/575728","url":null,"abstract":"By a simple differential thermal analysis (DTA) system, the concentration dependence of the glass transition temperatures (𝑇𝑔s) for the quaternary ammonium-type ionic liquid, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bromide [DEME][Br] and H2O mixtures, after quick precooling was measured as a function of water concentration 𝑥 (mol% H2O). We compared the results with the previous results of [DEME][I]-H2O and [DEME][BF4]-H2O mixtures in which a double-glass transition behavior was observed. Remarkably, the [DEME][Br]-H2O mixtures basically show one-𝑇𝑔 behavior and the 𝑇𝑔 decreases monotonically with increasing H2O content up to around 𝑥=91.5. But it suddenly jumps to higher 𝑇𝑔 value at a specific 𝑥=∼92. At this very limited point, two 𝑇𝑔s (𝑇𝑔1,𝑇𝑔2) which we might consider as a transition state from the structure belonging to the 𝑇𝑔1 group to another one due to the 𝑇𝑔2 group were observed. These results clearly reflect the difference in the anionic effects among Br−, I−, and BF4−. The end of the glass-formation region of [DEME][Br]-H2O mixtures is around 𝑥=98.9 and moves to more water-rich region as compared to those of [DEME][BF4]-H2O (𝑥=96.0) and [DEME][I]-H2O (𝑥=95.0) mixtures.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86785123","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 water desorption process of a mixture of room temperature ionic liquid (N, N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate) and water was investigated via simultaneous X-ray diffraction and differential scanning calorimetry (DSC) measurements, in which relative humidity was controlled by a water vapor generator. In these measurements, H2O concentration was estimated by the peak position of the principal peak in X-ray diffraction patterns, and the thermal property associated with a mixing state was detected by a DSC thermograph. In addition, the density of the mixture was measured as a macroscopic property. In situ observations revealed that the thermally unstable mixing state in the water-rich region has an important correlation with density and thermal and structural properties.
{"title":"Water Desorption Process in Room Temperature Ionic Liquid-HO Mixtures: N, N-diethyl-N-methyl-N-(2-methoxyethyl) Ammonium Tetrafluoroborate","authors":"H. Abe, Tomohiro Mori, Y. Imai, Y. Yoshimura","doi":"10.1155/2012/351968","DOIUrl":"https://doi.org/10.1155/2012/351968","url":null,"abstract":"A water desorption process of a mixture of room temperature ionic liquid (N, N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate) and water was investigated via simultaneous X-ray diffraction and differential scanning calorimetry (DSC) measurements, in which relative humidity was controlled by a water vapor generator. In these measurements, H2O concentration was estimated by the peak position of the principal peak in X-ray diffraction patterns, and the thermal property associated with a mixing state was detected by a DSC thermograph. In addition, the density of the mixture was measured as a macroscopic property. In situ observations revealed that the thermally unstable mixing state in the water-rich region has an important correlation with density and thermal and structural properties.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85270979","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}
Matias O. Maggiolo, Francisco J. Passamonti, A. Chialvo
The experimental evaluationof the vapor pressure of saturated aqueous solutionsof potassiumsulfate wascarried out in the range of temperatures 310K ≤ T ≤ 345K. The experimental data were used to determine the corresponding values of the water activity in such solutions.The analytical expressions as a function of temperature of both, vapor pressure and water activity, were obtained from the correlation of the experimental results. The vapor pressure expression was also extrapolated to a different temperature range in order to make a comparison with the results obtained by other authors.
{"title":"Vapor Pressure of Saturated Aqueous Solutions of Potassium Sulfate from 310 K to 345 K","authors":"Matias O. Maggiolo, Francisco J. Passamonti, A. Chialvo","doi":"10.1155/2011/432132","DOIUrl":"https://doi.org/10.1155/2011/432132","url":null,"abstract":"The experimental evaluationof the vapor pressure of saturated aqueous solutionsof potassiumsulfate wascarried out in the range of temperatures 310K ≤ T ≤ 345K. The experimental data were used to determine the corresponding values of the water activity in such solutions.The analytical expressions as a function of temperature of both, vapor pressure and water activity, were obtained from the correlation of the experimental results. The vapor pressure expression was also extrapolated to a different temperature range in order to make a comparison with the results obtained by other authors.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77665594","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 effects of synthetic food colorants like tartrazine (TTZ), sunset yellow (SY), and erythrosine (ETS) on the binding reaction between ciprofloxacin hydrochloride (CPFX) and bovine serum albumin (BSA) were investigated by fluorescence spectroscopy in the aqueous solution of pH = 7.40. Results showed that CPFX caused the fluorescence quenching of BSA through a static quenching procedure and the primary binding site was located at subdomain IIA of BSA (site I). According to the calculated thermodynamic parameters, it confirmed that CPFX bound to BSA by electrostatic interaction. In addition, the colorants affected the formation of BSA-CPFX complex. This resulted in an increase of the free, biological active fraction of CPFX. The binding distance of BSA-CPFX systems was evaluated according to Forster's theory. Results suggested that the binding distance were increased in the presence of synthetic food colorants.
{"title":"Investigation on the Competition Interaction of Synthetic Food Colorants and Ciprofloxacin Hydrochloride with Bovine Serum Albumin by Fluorescence Spectroscopy","authors":"Bao-Sheng Liu, Chao Yang, Jing Wang, Chunli Xue, Yun-kai Lü","doi":"10.1155/2011/137531","DOIUrl":"https://doi.org/10.1155/2011/137531","url":null,"abstract":"The effects of synthetic food colorants like tartrazine (TTZ), sunset yellow (SY), and erythrosine (ETS) on the binding reaction between ciprofloxacin hydrochloride (CPFX) and bovine serum albumin (BSA) were investigated by fluorescence spectroscopy in the aqueous solution of pH = 7.40. Results showed that CPFX caused the fluorescence quenching of BSA through a static quenching procedure and the primary binding site was located at subdomain IIA of BSA (site I). According to the calculated thermodynamic parameters, it confirmed that CPFX bound to BSA by electrostatic interaction. In addition, the colorants affected the formation of BSA-CPFX complex. This resulted in an increase of the free, biological active fraction of CPFX. The binding distance of BSA-CPFX systems was evaluated according to Forster's theory. Results suggested that the binding distance were increased in the presence of synthetic food colorants.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89096189","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}
To describe the nonequilibrium states of a system, we introduce a new thermodynamic parameter—the lifetime of a system. The statistical distributions which can be obtained out of the mesoscopic description characterizing the behaviour of a system by specifying the stochastic processes are written down. The change in the lifetime values by interaction with environment is expressed in terms of fluxes and sources. The expressions for the nonequilibrium entropy, temperature, and entropy production are obtained, which at small values of fluxes coincide with those derived within the frame of extended irreversible thermodynamics. The explicit expressions for the lifetime of a system and its thermodynamic conjugate are obtained.
{"title":"Nonequilibrium Thermodynamics Based on the Distributions Containing Lifetime as a Thermodynamic Parameter","authors":"V. Ryazanov","doi":"10.1155/2011/203203","DOIUrl":"https://doi.org/10.1155/2011/203203","url":null,"abstract":"To describe the nonequilibrium states of a system, we introduce a new thermodynamic parameter—the lifetime of a system. The statistical distributions which can be obtained out of the mesoscopic description characterizing the behaviour of a system by specifying the stochastic processes are written down. The change in the lifetime values by interaction with environment is expressed in terms of fluxes and sources. The expressions for the nonequilibrium entropy, temperature, and entropy production are obtained, which at small values of fluxes coincide with those derived within the frame of extended irreversible thermodynamics. The explicit expressions for the lifetime of a system and its thermodynamic conjugate are obtained.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79676028","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 phase behaviour of mixtures of supercritical propene and a number of polypropenes, which have a similar density but significantly different molecular weights and tacticities, was investigated in a broad range of polymer weight fractions and temperatures at high pressures. The cloud-point pressures were measured optically, using a view cell which was equipped with two windows made of synthetic sapphire and a metal bellows to accurately adjust the pressure. The cloud-point pressures were found in the range from 29 to 37 MPa decreasing with increasing polymer weight fraction and increasing with increasing temperature and polymer molecular weight. The critical weight fraction was found below 2 to 6 wt.-%. Whereas the cloud-point pressures of atactic and syndiotactic samples were high and very similar, the isotactic species exhibit distinctly lower values. The results, extrapolated to lower temperatures, show good agreement with the literature data.
{"title":"Phase Behaviour of the System Propene/Polypropene at High Pressure","authors":"O. Ruhl, G. Luft, P. Brant, J. R. Shutt","doi":"10.1155/2011/282354","DOIUrl":"https://doi.org/10.1155/2011/282354","url":null,"abstract":"The phase behaviour of mixtures of supercritical propene and a number of polypropenes, which have a similar density but significantly different molecular weights and tacticities, was investigated in a broad range of polymer weight fractions and temperatures at high pressures. The cloud-point pressures were measured optically, using a view cell which was equipped with two windows made of synthetic sapphire and a metal bellows to accurately adjust the pressure. The cloud-point pressures were found in the range from 29 to 37 MPa decreasing with increasing polymer weight fraction and increasing with increasing temperature and polymer molecular weight. The critical weight fraction was found below 2 to 6 wt.-%. Whereas the cloud-point pressures of atactic and syndiotactic samples were high and very similar, the isotactic species exhibit distinctly lower values. The results, extrapolated to lower temperatures, show good agreement with the literature data.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80265643","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}
Reliable equations of state are very important in the design of refrigeration cycles, since thermodynamic properties can be calculated by simple differentiation. In this paper, a new method to calculate the parameters of any two-parameter equation of state is presented. The method is based on the use of Clapeyron equation and the experimental PVT data. This method was tested on a newly developed cubic equation of state and proved to be simple and fast. Results showed orders of magnitude enhancement in prediction of the saturated vapor pressure even near the critical region. The Percent Absolute Average Deviation (%AAD) was always less than 0.1 in the studied cases. It also showed that the parameters calculated using the original equation deviate strongly from the “experimental” values as the temperature decreases below the critical point. This method can be used to redefine the temperature dependences of these parameters and develop new mixing rules for the mixtures.
{"title":"A New Method to Calculate the Pure Component Parameters of Any Two-Parameter Equation of State","authors":"I. Aljundi","doi":"10.1155/2011/696548","DOIUrl":"https://doi.org/10.1155/2011/696548","url":null,"abstract":"Reliable equations of state are very important in the design of refrigeration cycles, since thermodynamic properties can be calculated by simple differentiation. In this paper, a new method to calculate the parameters of any two-parameter equation of state is presented. The method is based on the use of Clapeyron equation and the experimental PVT data. This method was tested on a newly developed cubic equation of state and proved to be simple and fast. Results showed orders of magnitude enhancement in prediction of the saturated vapor pressure even near the critical region. The Percent Absolute Average Deviation (%AAD) was always less than 0.1 in the studied cases. It also showed that the parameters calculated using the original equation deviate strongly from the “experimental” values as the temperature decreases below the critical point. This method can be used to redefine the temperature dependences of these parameters and develop new mixing rules for the mixtures.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83216794","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 extension of the saturation curve 𝑃𝑠(𝑇) on the PT diagram in the supercritical region for a number of monocomponent supercritical fluids by peak values for different thermophysical properties, such as heat capacities 𝐶𝑝 and 𝐶𝑣 and compressibility has been studied. These peaks signal about some sort of fluid structural transition in the supercritical region. Different methods give similar but progressively diverging curves 𝑃st(𝑇) for this transition. The zone of temperatures and pressures near these curves can be named as the zone of the fluid structural transition. The outstanding properties of supercritical fluids in this zone help to understand the physical sense of the fluid structural transition.
{"title":"Structural Transition in Supercritical Fluids","authors":"B. Sedunov","doi":"10.1155/2011/194353","DOIUrl":"https://doi.org/10.1155/2011/194353","url":null,"abstract":"The extension of the saturation curve 𝑃𝑠(𝑇) on the PT diagram in the supercritical region for a number of monocomponent supercritical fluids by peak values for different thermophysical properties, such as heat capacities 𝐶𝑝 and 𝐶𝑣 and compressibility has been studied. These peaks signal about some sort of fluid structural transition in the supercritical region. Different methods give similar but progressively diverging curves 𝑃st(𝑇) for this transition. The zone of temperatures and pressures near these curves can be named as the zone of the fluid structural transition. The outstanding properties of supercritical fluids in this zone help to understand the physical sense of the fluid structural transition.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89686155","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 Group Contribution Equation of State (GC-EoS) was extended to represent high-pressure phase equilibria behavior of mixtures containing mono-, di-, triglycerides, and carbon dioxide (CO2). For this purpose, the alcohol-ester and the alcohol-triglyceride binary group interaction parameters were regressed in this work, using experimental phase equilibria data from the literature. The capability of the parameters obtained was assessed by applying the GC-EoS model to simulate the supercritical CO2 fractionation of a complex glyceride mixture, which was produced by the ethanolysis of sunflower oil. Experimental data was obtained in a countercurrent packed extraction column at pressures ranging from 16 to 25 MPa and temperatures from 313 to 368 K. The GC-EoS model was applied in a completely predictive manner to simulate the phase equilibria behavior of the multistage separation process. The chemical analysis of the glyceride mixture allowed a significant simplification of its complex composition and thus, a simple and satisfactory simulation of the supercritical extraction process was achieved.
{"title":"Supercritical Phase Equilibria Modeling of Glyceride Mixtures and Carbon Dioxide Using the Group Contribution EoS","authors":"T. Fornari, D. Tenllado, C. Torres, G. Reglero","doi":"10.1155/2011/730960","DOIUrl":"https://doi.org/10.1155/2011/730960","url":null,"abstract":"The Group Contribution Equation of State (GC-EoS) was extended to represent high-pressure phase equilibria behavior of mixtures containing mono-, di-, triglycerides, and carbon dioxide (CO2). For this purpose, the alcohol-ester and the alcohol-triglyceride binary group interaction parameters were regressed in this work, using experimental phase equilibria data from the literature. \u0000The capability of the parameters obtained was assessed by applying the GC-EoS model to simulate the supercritical CO2 fractionation of a complex glyceride mixture, which was produced by the ethanolysis of sunflower oil.\u0000Experimental data was obtained in a countercurrent packed extraction column at pressures ranging from 16 to 25 MPa and temperatures from 313 to 368 K. The GC-EoS model was applied in a completely predictive manner to simulate the phase equilibria behavior of the multistage separation process. The chemical analysis of the glyceride mixture allowed a significant simplification of its complex composition and thus, a simple and satisfactory simulation of the supercritical extraction process was achieved.","PeriodicalId":17290,"journal":{"name":"Journal of Thermodynamics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79185783","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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