International Journal of Thermal Sciences最新文献

{"title":"“Heat transfer analysis in 10 PPI copper metal foam using graphene-water nanofluid: Experimental study”","authors":"Swapnil Belorkar,&nbsp;Shrikant Londhe","doi":"10.1016/j.ijthermalsci.2024.109574","DOIUrl":"10.1016/j.ijthermalsci.2024.109574","url":null,"abstract":"<div><div>Thermal management of the modern electronic devices is one of the critical areas where innovative approaches are explored that include cooling using liquid, phase change materials, and employing microchannels, and porous metal foams along with the use of nanofluid. There are numerous analytical and simulation studies along with few experimental studies that used different water-nanoparticles (viz., CuO, Al₂O and TiO₂) combinations to flow through the metal foam to enhance the heat transfer. However, the use of Graphene-H₂O nanofluid along with porous metal foam is not much explored. This study investigates the thermal performance and hydraulic features of Graphene-H₂O nanofluid since it has some unique thermal characteristics which differentiate it from other nanofluids. Further, slightly wider range of Reynolds number is addressed which extends from 300 to 1900, as against up to 1200 in the earlier studies. The volumetric concentrations (φ) of Graphene are varied from 0.1 % to 0.5 %. The investigation is carried out for a cavity that contains copper metal lattice porous structure having 95 % porosity and 10 PPI pore density. The parameters addressed include heat transfer coefficient, Nusselt number, average wall temperature of metal foam, pressure drop &amp; friction coefficient. The results revealed that the heat transfer coefficient increases with concentration of nanofluid and for 0.5 % concentration, it increases 3.81 times and 6.89 times, respectively, for Re = 315 and Re = 1895, when compared with that for plain distilled water. The corresponding significant reduction in the heat sink temperature to the tune of 10.67 % and 13.10 % is observed, respectively, for Re = 315 &amp; Re = 1785.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109574"},"PeriodicalIF":4.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Convective-radiative heat exchange in a cube with a flat heated element under the rotation effect around coordinate axis","authors":"Stepan A. Mikhailenko ,&nbsp;Bernardo Buonomo ,&nbsp;Oronzio Manca ,&nbsp;Mikhail A. Sheremet","doi":"10.1016/j.ijthermalsci.2024.109577","DOIUrl":"10.1016/j.ijthermalsci.2024.109577","url":null,"abstract":"<div><div>The production of a various engineering systems is accompanied by studies of liquid flow structures and thermal energy patterns. Many engineering systems in electronics and energy are affected by rotation and an important task becomes the description of physical phenomena under rotational effects. This investigation is dedicated to convective-radiative thermal and mass transport inside a rotating cube having a flat heated element placed on the bottom surface. The rotation of the cube around each of the axes of Cartesian coordinates has been considered. Governing equations based on mass, momentum and energy conservation laws are written employing the non-primitive variables. The set of control equations is resolved by the finite difference schemes. The influences of angular velocity, rotation axis orientation, and emissivity of surfaces on the intensity of heat transfer have been shown. Temperature patterns for various rotation angles are presented and described in detail. The results demonstrate that rotation around the vertical axis shows a steady-state of the Nusselt numbers, while rotation around the horizontal axis shows the periodic changes. It is interesting that similar heat exchange modes are formed during rotation around horizontal axes. More intensive convective and radiative heat exchange is observed in the case of rotation around an axis at which the cooling walls change their position.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109577"},"PeriodicalIF":4.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Documenting weld pool behavior differences in variable-gap laser self-melting and wire-filling welding of titanium alloys","authors":"Yuhang Duan,&nbsp;Jianfeng Wang,&nbsp;Xuan Yin,&nbsp;Chao Ma,&nbsp;Xiaohong Zhan","doi":"10.1016/j.ijthermalsci.2024.109550","DOIUrl":"10.1016/j.ijthermalsci.2024.109550","url":null,"abstract":"<div><div>In large-scale welding processes involving complex geometries, variations in gap dimensions and the transition of filler wire form distinctive molten pool flow behaviors, significantly affecting weld formation and quality. This paper investigates the differences in the laser self-melting and wire-filling welding pool behavior of titanium alloy with variable gaps through both simulation and experimentation. An innovative three-dimensional transient heat-flow coupling model is developed to simulate laser welding with variable gap structures, incorporating the dynamics of the welding wire-filling process. The different laser welding modes and the filling process under the variable gap structure were numerically simulated. The results indicate that the maximum flow rate of the laser self-melting pool remains stable in proximity to the keyhole, reaching a maximum of approximately 2.491 m/s, with molten metal entering through the area surrounding the keyhole. As the gap size gradually increases to 0.2 mm during the laser self-fusion welding stage, keyhole instability becomes more pronounced. In transitioning from laser self-fusion to wire-filling welding, the welding wire behavior can be divided into three stages. The molten metal at the end of the welding wire is transferred to the liquid melt pool through a liquid metal bridge. The flow rate of this bridge initially rises before gradually decreasing, reaching a maximum flow rate of 1.606 m/s. Notably, the welding wire lags approximately 0.6 mm behind the laser's focal point, with the narrowest width of the liquid bridge measuring about 0.89 mm. Based on the simulation results and considering the melting transition time of the welding wire, the initiation time for the welding wire has been further adjusted to the first 10 ms when the gap threshold reaches 0.2 mm. Experimental verification confirms the successful laser welding of a 2 mm variable gap structure thin plate. This study elucidates the melt pool flow, keyhole fluctuations, and metal transition behaviors during the laser welding process, contributing to a deeper understanding of the complex heat and mass transfer dynamics inherent in variable gap structure laser self-melting and wire-filling welding. Ultimately, these insights aim to enhance the application of laser welding in adaptive welding for large structural components.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109550"},"PeriodicalIF":4.9,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elucidating effects of form factors on thermal and aging behavior of cylindrical lithium-ion batteries","authors":"Subham Khange,&nbsp;Ashwini Kumar Sharma","doi":"10.1016/j.ijthermalsci.2024.109564","DOIUrl":"10.1016/j.ijthermalsci.2024.109564","url":null,"abstract":"<div><div>Cylindrical lithium-ion cells are commercially available in different form factors, e.g., 18650, 21700, 26650, 32700 and 4680. The larger 4680 cells are gaining popularity, especially after the patent filing by Tesla. This paper aims to perform a comparative analysis of the thermal and aging behavior of different form factors using NMC–graphite chemistry during prolonged cycling at moderate operating conditions. A physics-based aging model for lithium-ion batteries is introduced, incorporating side reactions such as solid electrolyte interface (SEI) formation, SEI reformation due to graphite layer cracking, and lithium plating. During cycling, the cell temperature increases with time for all form factors due to internal heat generation. Notably, larger form factor cells experience higher temperatures, attributed to their inferior surface-to-volume ratio for heat dissipation, thereby accelerating both SEI formation and triggering lithium plating in subsequent cycles. This accelerated aging manifests in increased heat generation and prolonged charging for larger cells. The 4680 cell showed the highest rate of capacity loss with a 20% reduction over 480 cycles as compared to the 600 cycles of the 18650 cell. Highlighting accelerated aging in the larger cells due to suboptimal heat dissipation, this study underscores the pressing need for advanced thermal management strategies tailored to the unique challenges posed by larger cells.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109564"},"PeriodicalIF":4.9,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the combustion law of delayed ignition ethanol spill fire in longitudinal ventilation","authors":"Xue jing Hu,&nbsp;Cheng hao Ye,&nbsp;Jia xing Li,&nbsp;Mei qing Xia,&nbsp;Pei hong Zhang","doi":"10.1016/j.ijthermalsci.2024.109575","DOIUrl":"10.1016/j.ijthermalsci.2024.109575","url":null,"abstract":"<div><div>The environmental conditions under which sustained spill fire accidents occur are complex and variable, and this paper investigates experimentally the effect of longitudinal ventilation in tunnel on the combustion law of delayed ignition spill fires. Experiments on instantaneous ignition and spill fires with delay of 10 s, 20 s, and 30 s were carried out using ethanol at a spill rate of 78 ml/min under a longitudinal wind speed of 0–1.5 m/s in tunnel. The results show that with the increase of longitudinal wind speed the flame inclination of the spill fire increases and the flame length first increases and then decreases. By analysing the force on the fuel layer and the force on the flame, and combining with the previous research, the prediction models of flame length and flame inclination were established. In the case of longitudinal wind speed, the spill fire burning area increases and then decreases with the increase of wind speed, and there is a critical wind speed, which is related to the delayed ignition time. The heat loss of the substrate in the longitudinal wind and the influence of the flame morphology on the thermal radiation feedback of the flame were considered, and it was found that the heat transfer of the fuel layer with the increase of the wind speed was gradually transitioned from the radiation dominated to the convection dominated. It was found that there was a general trend of increasing combustion rate with increasing wind speed and delayed ignition time.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109575"},"PeriodicalIF":4.9,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on hydrothermal performance in a microchannel with gradient array of ribs and pin fins","authors":"Chunquan Li ,&nbsp;Yuanhao Zheng ,&nbsp;Hongyan Huang,&nbsp;Wencong Zhang,&nbsp;Yilong Hu,&nbsp;Yuling Shang","doi":"10.1016/j.ijthermalsci.2024.109562","DOIUrl":"10.1016/j.ijthermalsci.2024.109562","url":null,"abstract":"<div><div>An innovative microchannel heat sink (MCHS-GDRPF) with gradient array of ribs and pin fins is proposed to address the heat thermal management of high heat flux densities and ensure temperature uniformity. This heat sink combines the cooling advantages of ribs and pin fins, with the structural dimensions of the ribs and pin fins increasing linearly along the flow direction. Three-dimensional numerical simulations are utilized to assess the impacts of different gradient array patterns, relative rib-pin fins diameter and height on hydrothermal performance and temperature uniformity. Additionally, a comprehensive comparison of hydrothermal performance between the MCHS-GDRPF and four other microchannels with similar structured arrangements is presented. The results show that at a Reynolds number of 622, the surface temperature of the heat source is reduced by <span><math><mrow><mn>28</mn><mo>.</mo><mn>59</mn><mspace></mspace><mtext>K</mtext></mrow></math></span>, temperature uniformity is improved by 73.4%, the Nusselt number exhibits a 195.1% enhancement, and the performance evaluation criterion (PEC) attains a value of 1.366. Overall, this structure effectively ensures temperature uniformity and enhances heat dissipation capacity.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109562"},"PeriodicalIF":4.9,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study on vibration heat transfer enhancement of multi-configured blunt-headed cylinder with fin device","authors":"Xiaoya Zhang,&nbsp;Derong Duan,&nbsp;Muhao Wang,&nbsp;Changqing Gao,&nbsp;Xuefeng Yang,&nbsp;Hui Zhang","doi":"10.1016/j.ijthermalsci.2024.109573","DOIUrl":"10.1016/j.ijthermalsci.2024.109573","url":null,"abstract":"<div><div>The large-scale flow-induced deformation is an effective heat transfer enhancement technology. Then, a blunt-headed cylinder with fin (BHC-F) was proposed to evaluate the heat transfer enhancement performance using flow-induced vibration with different configuration (incident angle <em>Φ</em>). The two-way fluid structure interaction method was utilized to explore the vibration response, flow field and heat transfer performance of BHC-F at Reynolds numbers <em>Re</em> = 500–1500. Vibration results found that the vibration displacement of BHC-F increased with the increase of <em>Φ</em> (0°–180°), which leaded to the acceleration of flow boundary layer separation. When <em>Φ</em> = 180°, the peak displacement of BHC-F reached 3.12 mm, which was 61.66 % and 34.48 % higher than that of <em>Φ</em> = 0° and 90°, respectively. At this time, heat transfer enhancement was obtained because the thermal boundary layer was reduced due to the interaction between the vortex and the wall. In addition, the <em>PEC</em> under all configurations were all greater than 1, indicating that BHC-F achieved the purpose of enhanced heat transfer. The increase of <em>Re</em> has a positive effect on the heat transfer enhancement of BHC-F. When <em>Re</em> = 1500, the maximum heat transfer enhancement of BHC-F-90° reached 13.8 %, which was 62.3 and 26.6 times higher than that of BHC-F-0° and BHC-F-180°. This study establishes a theoretical foundation for employing flow-induced vibration in heat transfer enhancement applications and offers technical support for enhancing the overall performance of heat exchangers.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109573"},"PeriodicalIF":4.9,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interlayer surface modification modulating thermal transport at Si/Gr/HEA heterostructure interfaces","authors":"Yinjie Shen ,&nbsp;Haiying Yang ,&nbsp;Kunlong Cao ,&nbsp;Ping Yang","doi":"10.1016/j.ijthermalsci.2024.109565","DOIUrl":"10.1016/j.ijthermalsci.2024.109565","url":null,"abstract":"<div><div>We investigate the effect of nanoslot modification and defects on the interfacial thermal resistance (ITR) of silicon/graphene/FeNiCrCoCu vdW heterostructures (Si/Gr/HEA) by using molecular dynamics (MD). The results show the triangular and rectangular nanoslots have opposite trends for changing on ITR. When the number of nanoslots in the system increases to seven, the ITR of the triangular nanoslots decreases by 41.47 %. It shows that ITR strongly depends on the type and concentration of all three defects. By analyzing the phonon density of states (<em>PDOS</em>), phonon coupling coefficient (<em>S</em>), phonon participation rate (<em>PPR</em>), and phonon coupling spectral decomposition (<em>PCSD</em>), the results show that the construction of triangular nanoslots induced strong local pressure in Gr layer, resulting in enhanced interface phonon coupling and decreased ITR. The decrease of ITR caused by single vacancy defect (SV) is mainly due to the increase of PPR in 10–15 THz and 22–30 THz frequencies in the Gr layer, and the increase of non-localized phonon mode. This means that it is possible to improve the heat conduction of Si/Gr/HEA vdW heterogeneous devices.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109565"},"PeriodicalIF":4.9,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142742994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced flow boiling by manipulating two-phase flow in Tesla channel heat sink using HFE-7100","authors":"Jingwei Han,&nbsp;Zhaoxuan Liu,&nbsp;Wenming Li,&nbsp;Li Shan","doi":"10.1016/j.ijthermalsci.2024.109571","DOIUrl":"10.1016/j.ijthermalsci.2024.109571","url":null,"abstract":"<div><div>Flow boiling of dielectric fluids in copper microchannel heat sinks is highly desirable for cooling large-sized insulated gate bipolar transistor (IGBT) power electronic modules. However, dielectric fluids present challenges in flow boiling because of their unfavorable thermophysical properties. These factors make it difficult to enhance critical heat flux (CHF) without precooling. To address this, we developed a large copper heat sink (10 cm × 5 cm) with Tesla microchannels designed to suppress vapor backflow and promote intense fluid mixing. The microchannels have a high length to hydrodynamic diameter ratio of approximately 220, significantly higher than those in previous studies. Flow boiling experiments using HFE-7100 were conducted for both Tesla and plain-wall microchannels. Tesla channels demonstrated a 26.2 % increase in CHF and a 120 % improvement in heat transfer coefficient (HTC). These enhancements are attributed to the vapor backflow suppression and improved fluid mixing. Moreover, the standard deviation of wall temperature in plain-wall microchannels was 10 times higher than in Tesla channels, highlighting the effectiveness of the periodic Tesla valves in reducing two-phase flow instabilities. Flow pattern visualization was conducted to further understand the mechanism behind vapor regulation, clarifying the role of Tesla valves in controlling vapor backflow. This study demonstrates the potential of dielectric fluids in Tesla microchannels for flow boiling applications, offering a promising solution for cooling large electronics.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109571"},"PeriodicalIF":4.9,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation on the suitability of conventional film hole under pulsed detonation incoming flow conditions","authors":"Ji-Chen Li,&nbsp;Hui-Ren Zhu,&nbsp;Lin Ye,&nbsp;Long-Xi Zheng,&nbsp;Dao-En Zhou,&nbsp;Cun-Liang Liu","doi":"10.1016/j.ijthermalsci.2024.109570","DOIUrl":"10.1016/j.ijthermalsci.2024.109570","url":null,"abstract":"<div><div>As a novel and efficient engine, the pulse detonation engine will increasingly demand advanced cooling technology. Film cooling, widely utilized in conventional aero engines, is also anticipated to be employed in pulse detonation engines. However, further investigation is required to assess the suitability of conventional film holes for pulse detonation engines. This study determines the cooling characteristics of a plate with a single film hole in a pulse detonation engine operating at a frequency of 30Hz through numerical calculations. The types of film holes considered include cylindrical, fan-shaped, laid-back, laid-back fan-shaped, and converging-slot holes, all of which have a diameter of 1 mm and an inclination angle of 30°. The single pulse detonation period is divided into stages: initiation and detonation wave propagation, gas exhaust, and refilling. During the initiation and detonation wave propagation stage, the film hole exhibits a significant backflow phenomenon, with the magnitude of gas backflow positively correlated with the outlet area of the film hole. Notably, the converging-slot hole experiences the least amount of gas backflow, with an exit area 33 % smaller than that of cylindrical holes and a corresponding 18 % reduction in backflow enthalpy. Throughout the initiation and detonation wave propagation stage, the backflow gas carries an enthalpy ranging from 0.43 J to 0.63 J into each individual film hole. In the gas exhaust stage, the blowing ratio increases over time as the mainstream pressure decreases, leading to a rapid decline in the film cooling effectiveness of the cylindrical and laid-back holes. The converging-slot holes have the largest film covering area, thus exhibiting the highest film cooling effectiveness, which is 53 % higher than that of the cylindrical hole. In the refilling stage, the mainstream temperature reaches the same level as the secondary flow temperature, rendering the consideration of the cooling characteristics of the film hole unnecessary. Under the conditions of this study, the converging-slot hole is found to be most suitable for cooling the pulse detonation engine.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"210 ","pages":"Article 109570"},"PeriodicalIF":4.9,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}