The temperature rise in compact silicon devices is predicted at present by solving the heat diffusion equation based on Fourier’s law. The validity of this approach needs to be carefully examined for semiconductor devices in which the region of strongest electronphonon coupling is narrower than the phonon mean free path, Λ, and for devices in which Λ is comparable to or exceeds the dimensions of the device. Previous research estimated the effective phonon mean free path in silicon near room temperature to be near 300 nm, which is already comparable with the minimum feature size of current generation transistors. This work numerically integrates the phonon Boltzmann transport equation (BTE) within a two-dimensional Silicon-on-Insulator (SOI) transistor. The BTE is coupled with the classical heat diffusion equation, which is solved in the silicon dioxide layer beneath a transistor with a channel length of 400 nm. The sub-continuum simulations yield a peak temperature rise that is 159 percent larger than predictions using only the classical heat diffusion equation. This work will facilitate the development of simpler calculation strategies, which are appropriate for commercial device simulators.
{"title":"Sub-Continuum Simulations of Heat Conduction in Silicon-on-Insulator Transistors","authors":"P. Sverdrup, Y. Ju, K. Goodson","doi":"10.1115/1.1337651","DOIUrl":"https://doi.org/10.1115/1.1337651","url":null,"abstract":"\u0000 The temperature rise in compact silicon devices is predicted at present by solving the heat diffusion equation based on Fourier’s law. The validity of this approach needs to be carefully examined for semiconductor devices in which the region of strongest electronphonon coupling is narrower than the phonon mean free path, Λ, and for devices in which Λ is comparable to or exceeds the dimensions of the device. Previous research estimated the effective phonon mean free path in silicon near room temperature to be near 300 nm, which is already comparable with the minimum feature size of current generation transistors. This work numerically integrates the phonon Boltzmann transport equation (BTE) within a two-dimensional Silicon-on-Insulator (SOI) transistor. The BTE is coupled with the classical heat diffusion equation, which is solved in the silicon dioxide layer beneath a transistor with a channel length of 400 nm. The sub-continuum simulations yield a peak temperature rise that is 159 percent larger than predictions using only the classical heat diffusion equation. This work will facilitate the development of simpler calculation strategies, which are appropriate for commercial device simulators.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131066334","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}
Due to the small size of structures in modern microdevices, surface forces can create undesirable adhesion between microstructures, which is referred to as stiction. Prior investigations have used ultrashort-pulse lasers to recover stiction-failed microcantilevers. The current experiments study the use of a 400 ns, 1064 nm, Nd:YAG laser to free polycrystalline silicon microcantilevers stuck to the underlying substrate. The results show that a Nd:YAG, 1064 nm laser is capable of recovering failed microstructures with yields exceeding those reported in earlier studies. Yields of 100 percent for cantilevers up to 1 mm in length were demonstrated for several laser operating conditions. The yields are strongly dependent on laser fluence and slightly dependent on exposure time, with a single-shot at 160 mJ/cm2 resulting in yields around 60 percent.
{"title":"Nanosecond Laser Experiments of Microstructure Adhesion Reduction","authors":"J. W. Rogers, L. Phinney","doi":"10.1115/imece1999-1059","DOIUrl":"https://doi.org/10.1115/imece1999-1059","url":null,"abstract":"\u0000 Due to the small size of structures in modern microdevices, surface forces can create undesirable adhesion between microstructures, which is referred to as stiction. Prior investigations have used ultrashort-pulse lasers to recover stiction-failed microcantilevers. The current experiments study the use of a 400 ns, 1064 nm, Nd:YAG laser to free polycrystalline silicon microcantilevers stuck to the underlying substrate. The results show that a Nd:YAG, 1064 nm laser is capable of recovering failed microstructures with yields exceeding those reported in earlier studies. Yields of 100 percent for cantilevers up to 1 mm in length were demonstrated for several laser operating conditions. The yields are strongly dependent on laser fluence and slightly dependent on exposure time, with a single-shot at 160 mJ/cm2 resulting in yields around 60 percent.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130200084","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 mechanism of light emission from a single bubble sonoluminescence (SBSL) was formulated by assuming that the source for the light emission is bremsstrahlung in partially ionized gases. Also the spectrum was measured and the observed results were compared with the calculated ones. Calculated and experimental results yield common spectral behavior in the visible region: the spectral radiance shows power-law dependence on wavelength with an exponent of −2.5. The SBSL spectrum which is characterized by the continuous one with no major peaks has been confirmed experimentally.
{"title":"Radiation Mechanism for a Single Bubble Sonoluminescence","authors":"J. Jeon, I. Yang, J. Na, H. Kwak","doi":"10.1143/JPSJ.69.112","DOIUrl":"https://doi.org/10.1143/JPSJ.69.112","url":null,"abstract":"\u0000 A mechanism of light emission from a single bubble sonoluminescence (SBSL) was formulated by assuming that the source for the light emission is bremsstrahlung in partially ionized gases. Also the spectrum was measured and the observed results were compared with the calculated ones. Calculated and experimental results yield common spectral behavior in the visible region: the spectral radiance shows power-law dependence on wavelength with an exponent of −2.5. The SBSL spectrum which is characterized by the continuous one with no major peaks has been confirmed experimentally.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124895727","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 radial heat conduction in the tube wall of dielectric thin tubes is studied in this work. An equation of phonon radiative transfer (EPRT) is used in association with nodal approximation technique for examining the heat transport in the thin tubes. The effective thermal conductivity of thin tubes is calculated based on the heat flux in the middle surface of the tubes. Results indicate that the energy distribution in the annulus is dominated by phonons excited by outer surface. Consequently, the temperature distribution is considerably affected by the temperature of outer surface. In addition to tube wall thickness, R2-R1, which was usually considered as the size effect on heat conduction, the curvature effect would significantly change the heat flux across the tube wall and consequently affect the effective thermal conductivity.
{"title":"Microscale Heat Conduction in Dielectric Thin Tubes","authors":"Long-Jye Sheu, Jenn-Der Lin, F. Chou","doi":"10.1115/imece1999-1070","DOIUrl":"https://doi.org/10.1115/imece1999-1070","url":null,"abstract":"\u0000 The radial heat conduction in the tube wall of dielectric thin tubes is studied in this work. An equation of phonon radiative transfer (EPRT) is used in association with nodal approximation technique for examining the heat transport in the thin tubes. The effective thermal conductivity of thin tubes is calculated based on the heat flux in the middle surface of the tubes. Results indicate that the energy distribution in the annulus is dominated by phonons excited by outer surface. Consequently, the temperature distribution is considerably affected by the temperature of outer surface. In addition to tube wall thickness, R2-R1, which was usually considered as the size effect on heat conduction, the curvature effect would significantly change the heat flux across the tube wall and consequently affect the effective thermal conductivity.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125112145","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 boundary element formulation developed previously by the authors for incompressible isothermal viscous fluid flows is extended for non-isothermal flows governed by Boussinesq equations. The new boundary element method is applied to the classical Rayleigh-Benard problem and to a stratified flow over a backward-facing step. In all cases, the boundary element results are in good agreement with published finite element solutions. However, in some instances, the boundary element solutions are more accurate, particularly in terms of resolving surface tractions and heat fluxes.
{"title":"Benchmark Boundary Element Solutions for Some Problems Governed by the Boussinesq Equations","authors":"M. Grigoriev, G. Dargush","doi":"10.1115/imece1999-1090","DOIUrl":"https://doi.org/10.1115/imece1999-1090","url":null,"abstract":"\u0000 The boundary element formulation developed previously by the authors for incompressible isothermal viscous fluid flows is extended for non-isothermal flows governed by Boussinesq equations. The new boundary element method is applied to the classical Rayleigh-Benard problem and to a stratified flow over a backward-facing step. In all cases, the boundary element results are in good agreement with published finite element solutions. However, in some instances, the boundary element solutions are more accurate, particularly in terms of resolving surface tractions and heat fluxes.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131281566","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 the present study we apply an artificial neural network to predict the operation of a humid air-water fin-tube compact heat exchanger. The network configuration is of the feedforward type with a sigmoid activation function and a backpropagation algorithm. Published experimental data, corresponding to humid air flowing over the heat exchanger tubes and water flowing inside them, are used to train the neural network. After training with known experimental values of the humid-air flow rates, dry-bulb and wet-bulb inlet temperatures for various geometrical configurations, the j-factor and heat transfer rate predictions of the network were tested against the experimental values. Comparisons were made with published predictions of power-law correlations which were obtained from the same data. The results demonstrate that the neural network is able to predict the performance of this heat exchanger much better than the correlations.
{"title":"Prediction of Humid Air Heat Exchanger Performance Using Artificial Neural Networks","authors":"A. Pacheco-Vega, M. Sen, K. T. Yang, R. McClain","doi":"10.1115/imece1999-1087","DOIUrl":"https://doi.org/10.1115/imece1999-1087","url":null,"abstract":"\u0000 In the present study we apply an artificial neural network to predict the operation of a humid air-water fin-tube compact heat exchanger. The network configuration is of the feedforward type with a sigmoid activation function and a backpropagation algorithm. Published experimental data, corresponding to humid air flowing over the heat exchanger tubes and water flowing inside them, are used to train the neural network. After training with known experimental values of the humid-air flow rates, dry-bulb and wet-bulb inlet temperatures for various geometrical configurations, the j-factor and heat transfer rate predictions of the network were tested against the experimental values. Comparisons were made with published predictions of power-law correlations which were obtained from the same data. The results demonstrate that the neural network is able to predict the performance of this heat exchanger much better than the correlations.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133355139","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 three-dimensional model is developed to investigate flow and conjugate heat transfer in the microchannel-based heat sink for electronic packaging applications. The incompressible laminar flow Navier-Stokes equations of motion as well as the energy conservation equations for the fluid and solid are employed as the governing model equations which are numerically solved using the generalized single-equation framework for solving conjugate problems. First, the theoretical model developed is validated by comparing the model predictions of the thermal resistance and the friction coefficient with available experimental data for a wide range of Reynolds numbers. Then, the parametric calculations are performed to investigate the effects of different working fluids, solid substrate materials and channel geometry on conjugate heat transfer in the microchannel heat sink. The bulk and wall temperature and heat flux distributions as well as the average heat transfer characteristics are reported and discussed. Important practical design recommendations are also provided regarding the cooling efficiency of the microchannel heat sink.
{"title":"Analysis of Conjugate Heat Transfer in a Three-Dimensional Microchannel Heat Sink for Cooling of Electronic Components","authors":"A. Fedorov, R. Viskanta","doi":"10.1115/imece1999-1066","DOIUrl":"https://doi.org/10.1115/imece1999-1066","url":null,"abstract":"\u0000 A three-dimensional model is developed to investigate flow and conjugate heat transfer in the microchannel-based heat sink for electronic packaging applications. The incompressible laminar flow Navier-Stokes equations of motion as well as the energy conservation equations for the fluid and solid are employed as the governing model equations which are numerically solved using the generalized single-equation framework for solving conjugate problems.\u0000 First, the theoretical model developed is validated by comparing the model predictions of the thermal resistance and the friction coefficient with available experimental data for a wide range of Reynolds numbers. Then, the parametric calculations are performed to investigate the effects of different working fluids, solid substrate materials and channel geometry on conjugate heat transfer in the microchannel heat sink.\u0000 The bulk and wall temperature and heat flux distributions as well as the average heat transfer characteristics are reported and discussed. Important practical design recommendations are also provided regarding the cooling efficiency of the microchannel heat sink.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"415 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117299652","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 method for evaluating the numerically introduced dispersion in finite element solutions to the one-dimensional heat equation is presented. The dispersion is quantified for linear and quadratic elements as a function of time step, mesh refinement and capacitance matrix formulation. It is demonstrated that an analysis of the dispersion is a useful tool in estimating the accuracy and in understanding the behavior of the numerical algorithm.
{"title":"The Dispersion in Finite Element Solutions to the One-Dimensional Heat Equation","authors":"A. Emery, W. Dauksher","doi":"10.1115/imece1999-1085","DOIUrl":"https://doi.org/10.1115/imece1999-1085","url":null,"abstract":"\u0000 A method for evaluating the numerically introduced dispersion in finite element solutions to the one-dimensional heat equation is presented. The dispersion is quantified for linear and quadratic elements as a function of time step, mesh refinement and capacitance matrix formulation. It is demonstrated that an analysis of the dispersion is a useful tool in estimating the accuracy and in understanding the behavior of the numerical algorithm.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131188544","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 detailed experimental and numerical study is carried out to investigate conjugate heat transfer in a horizontal channel with a heated section which simulates Chemical Vapor Deposition (CVD) processing. Since film quality, uniformity and deposition rate have strong dependence on temperature, the role of conjugate heat transfer in influencing temperature distribution is significant in thin film production. Experimental data obtained from this study provides physical insight into conjugate heat transfer effects and allows for comparison and validation of numerical conjugate heat transfer models. The basic characteristics of the flow and the thermal transport are studied. The numerical model is used to perform a parametric study of operational parameters, allowing for the characterization of conjugate heat transfer effects on temperature at the susceptor surface, reactor walls and the gas phase. The study yields valuable guidelines for the thermal design of CVD reactors.
{"title":"Experimental and Numerical Study of Conjugate Heat Transfer in a Horizontal Channel Heated From Below: Applications to CVD Processing","authors":"W. Chiu, C. J. Richards, Y. Jaluria","doi":"10.1115/imece1999-1071","DOIUrl":"https://doi.org/10.1115/imece1999-1071","url":null,"abstract":"\u0000 A detailed experimental and numerical study is carried out to investigate conjugate heat transfer in a horizontal channel with a heated section which simulates Chemical Vapor Deposition (CVD) processing. Since film quality, uniformity and deposition rate have strong dependence on temperature, the role of conjugate heat transfer in influencing temperature distribution is significant in thin film production. Experimental data obtained from this study provides physical insight into conjugate heat transfer effects and allows for comparison and validation of numerical conjugate heat transfer models. The basic characteristics of the flow and the thermal transport are studied. The numerical model is used to perform a parametric study of operational parameters, allowing for the characterization of conjugate heat transfer effects on temperature at the susceptor surface, reactor walls and the gas phase. The study yields valuable guidelines for the thermal design of CVD reactors.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132500140","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. Wan, V. Gupta, H. Zhang, A. Varshney, S. Sampath, V. Prasad, J. Fincke
Recently, several models have been developed to simulate the plasma spraying process. The present paper extends our previous model (Wan et al., 1999a) to the plasma spray system of two-component materials with two different feed nozzles. It accounts for plasma-particle interaction, particle heating/melting/evaporation and solidification on the substrate. A special visualization algorithm has been developed to demonstrate the effects of various parameters on particle conditions while in flight, growth of functionally graded materials and distribution of the two components in the coating. Visualization of thermal processes is a challenging task if it has to be used for materials design and system development. It requires special schemes for data management in a multivariate system that includes at least velocity, temperature and species in four co-ordinates (space and time). Our effort is focused on developing a visualization scheme which goes far beyond the process animation and can be ultimately used for virtual prototyping of the processes, an area that needs special research efforts. Simulation and visualization have been performed for spraying of zirconia and NiCrAlY powders, with many combinations of powder injection features, e.g., number of nozzles, nozzle location and injection velocity. The fluctuation of the voltage is also simulated and animated to show its effect on both plasma gas and particle behavior. The optimized operating parameters are deduced from the distribution of these two materials in the coating layer. Issues related to visualization are also discussed.
近年来，人们建立了几个模型来模拟等离子喷涂过程。本文将我们之前的模型(Wan et al.， 1999a)扩展到具有两种不同进料喷嘴的双组分材料等离子喷涂系统。它解释了等离子体-粒子相互作用，粒子加热/熔化/蒸发和基底上的凝固。开发了一种特殊的可视化算法来演示各种参数对飞行过程中颗粒状况的影响，功能梯度材料的生长以及两种组分在涂层中的分布。热过程的可视化是一项具有挑战性的任务，如果它必须用于材料设计和系统开发。它需要在多元系统中进行数据管理的特殊方案，该系统至少包括四个坐标(空间和时间)中的速度、温度和物种。我们的工作重点是开发一个可视化方案，它远远超出了过程动画，最终可以用于过程的虚拟原型，这是一个需要特别研究的领域。对氧化锆和NiCrAlY粉末的喷涂进行了仿真和可视化，使用了许多粉末喷射特征的组合，例如喷嘴数量、喷嘴位置和喷射速度。模拟和动画显示了电压的波动对等离子体气体和粒子行为的影响。根据这两种材料在涂层中的分布，推导出了优化的操作参数。还讨论了与可视化相关的问题。
{"title":"Modeling and Visualization of Plasma Spray Process for Depositing Functionally Graded Materials","authors":"Y. Wan, V. Gupta, H. Zhang, A. Varshney, S. Sampath, V. Prasad, J. Fincke","doi":"10.1115/imece1999-1096","DOIUrl":"https://doi.org/10.1115/imece1999-1096","url":null,"abstract":"\u0000 Recently, several models have been developed to simulate the plasma spraying process. The present paper extends our previous model (Wan et al., 1999a) to the plasma spray system of two-component materials with two different feed nozzles. It accounts for plasma-particle interaction, particle heating/melting/evaporation and solidification on the substrate. A special visualization algorithm has been developed to demonstrate the effects of various parameters on particle conditions while in flight, growth of functionally graded materials and distribution of the two components in the coating. Visualization of thermal processes is a challenging task if it has to be used for materials design and system development. It requires special schemes for data management in a multivariate system that includes at least velocity, temperature and species in four co-ordinates (space and time). Our effort is focused on developing a visualization scheme which goes far beyond the process animation and can be ultimately used for virtual prototyping of the processes, an area that needs special research efforts. Simulation and visualization have been performed for spraying of zirconia and NiCrAlY powders, with many combinations of powder injection features, e.g., number of nozzles, nozzle location and injection velocity. The fluctuation of the voltage is also simulated and animated to show its effect on both plasma gas and particle behavior. The optimized operating parameters are deduced from the distribution of these two materials in the coating layer. Issues related to visualization are also discussed.","PeriodicalId":306962,"journal":{"name":"Heat Transfer: Volume 3","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128305779","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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