Cryogenics最新文献

{"title":"Cryogenic helium flow in adiabatic capillary tubes: Numerical insights into choked flow and superfluid behavior in Joule-Thomson cryocoolers","authors":"Xin Zhang ,&nbsp;Longyu Yang ,&nbsp;Yixin Wang ,&nbsp;Xueshuo Shang ,&nbsp;Wendi Bao ,&nbsp;Ziyi Li ,&nbsp;Cheng Shao ,&nbsp;Zheng Cui","doi":"10.1016/j.cryogenics.2025.104043","DOIUrl":"10.1016/j.cryogenics.2025.104043","url":null,"abstract":"<div><div>The Joule-Thomson (J-T) effect, utilizing helium as the working fluid, is widely employed for refrigeration in the 1–4 K temperature range. The capillary tube, acting as a throttling element, plays a crucial role in providing flow resistance and regulating flow rates. However, critical information regarding helium flow in the capillary tube—such as the onset of choked flow, the existence of superfluid transition, and the dependence of flow rates and the cooling power on the geometric factors of the capillary tube and operating conditions—remains inadequately understood. This paper presents a numerical analysis investigating the flow dynamics and refrigeration characteristics of helium through adiabatic straight capillary tubes. The findings establish criteria for identifying the onset of choked flow and superfluid transition. Results indicate that helium flow within the capillary tube typically operates in the choked flow regime in practical applications. Should a superfluid transition occur, it takes place in the free expansion region outside the capillary tube, exerting minimal influence on the internal flow dynamics. Furthermore, sensitivity analysis identifies the inner diameter as a crucial parameter dictating the mass flow rate. Design guidelines are also provided for the optimal selection of capillary tubes in cryogenic applications.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104043"},"PeriodicalIF":1.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High temperature superconducting magnet system with a high pressure chamber at a cryogenic temperatures for neutron scattering investigations","authors":"Aleksandr Chernikov ,&nbsp;Ion Dobrin ,&nbsp;George Dumitru ,&nbsp;Sergey Kulikov ,&nbsp;Otilia Ana Culicov ,&nbsp;Dan Enache","doi":"10.1016/j.cryogenics.2025.104035","DOIUrl":"10.1016/j.cryogenics.2025.104035","url":null,"abstract":"<div><div>For the DN-12 neutron diffractometer at the IBR-2 reactor of the Frank Laboratory of Neutron Physics, JINR, a cryomagnetic system with horizontal arrangement based on a high temperature superconducting magnet generating a magnetic field of 4.6 T at a current of 290 A was designed, developed and tested. The unique cryomagnetic system is designed to study phases of condensed matter systems with neutron as a function of P,T,H. The configuration of the Helmholtz coil of a high-temperature superconducting magnet made it possible not only to achieve high uniformity of the magnetic field on the sample &gt; 99.68 % in the central zone of the magnet ± 20 mm around its center, but also to provide 360° access to the central region of the magnetic field in a perpendicular plane on the sample with the exception of four sectors of 12 degrees each due to the spacer design pillars. The magnetic axis is passing through its center. This configuration allows to simultaneously detect the neutron scattered on the sample using two neutron detectors positioned at angles of 45° and 90° to the axis of the neutron beam, respectively.</div><div>The HTS coils are double pancakes cooled via heat conduction using a Gifford-McMahon (G-M) cryocooler. The dimensions of the magnet, inner diameter 80 mm, outer diameter 200 mm, distance between the coils 40 mm, allow the installation of an inner cryostat with high pressure chamber that is cooled using the second G-M closed-cycle cryocooler and can create a pressure on the sample 10 GPa. The temperature of the magnet windings can vary in the range of 16–40 K depending on the temperature of the high pressure chamber with the sample that is regulated in the range of 3.6–150 K. The developed cryomagnetic system has reached all design parameters and is ready for testing on a neutron beam.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104035"},"PeriodicalIF":1.8,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Magnetic properties of Ni-Cu-Zn ferrite nanoparticles at cryogenic temperature probed under Mössbauer and VSM studies","authors":"K.S. Ramakrishna ,&nbsp;Ch. Srinivas ,&nbsp;E. Ranjith Kumar ,&nbsp;T. Pushpagiri ,&nbsp;Sher Singh Meena ,&nbsp;Pramod Bhatt ,&nbsp;D.L. Sastry","doi":"10.1016/j.cryogenics.2025.104040","DOIUrl":"10.1016/j.cryogenics.2025.104040","url":null,"abstract":"<div><div>This article presents a comprehensive analysis of magnetic properties of Ni<em>_x</em>Cu_0.1Zn_0.9−<em>_x</em>Fe₂O₄ (<em>x</em> = 0.5, 0.6, 0.7). Typical variation of bond angles supported the <em>A</em>-<em>B</em> superexchange interaction. The unsaturated magnetization even at higher applied field shows the core–shell interactions of present ferrite nanoparticles. Neel’s sublattice and core–shell models have been adopted to analyze the magnetic behaviour. The saturation magnetization is unevenly varying in both sintered ferrite samples. It was found to be in the range of 15.29–28.04 emu/g. The highest of saturation magnetization (28.04 emu/g) was reported for the ferrite composition Ni_0.7Cu_0.1Zn_0.4Fe₂O₄ sintered at 500 °C. The coercivity seems to be dependent on magnetic anisotropy. The cusp between the field cooled and zero field cooled curves revealed the large distribution of ferrite nanoparticles in different sizes. The blocking temperature increases in both sintered ferrite samples with the substitution of Ni²⁺. The blocking temperature depends on the variation of crystallite size. The appearance of quadruple and hyperfine spectral lines in Mössbauer spectra represent the distribution of ferrite nanoparticles in different sizes. The range of isomer shift (0.194 – 0.463 mm/s) is less than 0.5 mm/s that represents the presence of only high spin Fe³⁺ ions.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104040"},"PeriodicalIF":1.8,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and simulation study of LN2 active-pressurization in onboard LH2 storage and supply systems","authors":"Hao Qiu,&nbsp;Bifeng Yin,&nbsp;Fei Dong,&nbsp;Xuan Xie,&nbsp;Sheng Xu","doi":"10.1016/j.cryogenics.2025.104042","DOIUrl":"10.1016/j.cryogenics.2025.104042","url":null,"abstract":"<div><div>To prevent insufficient pressure within the onboard LH₂ storage tank during supply, which could lead to significant residual LH₂ that cannot be supplied, the design of the onboard LH₂ storage and supply system needs to consider the active-pressurization method of the LH₂ tank. To investigate whether the active-pressurization method can meet the active-pressurization performance requirements for low-temperature fluids in onboard LH₂ storage tanks, this study uses LN₂ as the working fluid. Experiments on active-pressurization and supply in the onboard LH₂ storage system were conducted, exploring the impact of different LN₂ fill levels on the active-pressurization rate and the pressure stability during the active-pressurization supply process. Based on the parameters of the LH₂ tank, a system simulation model was established. The maximum active-pressurization flow rate of the simulation model was calibrated according to the active-pressurization experimental data, further exploring the active-pressurization storage and supply characteristics of the onboard LH₂ tank. The results indicate that the active-pressurization supply simulation results, calibrated with the active-pressurization flow rate, show good consistency with the experimental data. As the supply flow rate increases, the active-pressurization maintaining pressure slightly decreases. When the liquid level drops too low and transitions to gaseous supply, the pressure inside the tank rapidly declines. At an ambient temperature of −10 °C, the active-pressurization can still offset the pressure drop caused by the supply. However, higher ambient temperatures increase the temperature difference during, leading to a higher evaporation rate inside the tank. The active-pressurization flow rate was corrected by the ratio of the densities and viscosities of LN₂ and LH₂ to investigate the situation of active-pressurization to exceed the critical pressure. When the LH₂ tank is actively pressurized to the critical pressure, there is still a return gas temperature difference close to 170 K, which is much higher than the 0 K of LN₂, thereby promoting the active-pressurization rate. This study explored the active-pressurization capability and influencing factors of onboard LH₂ storage tanks through LN₂ experiments and system simulation methods, providing a foundation for precise control of the active-pressurization supply in onboard LH₂ systems.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104042"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143429964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on catalytic conversion and flow characteristics of ortho-para hydrogen in tubular packed-bed converters at liquid nitrogen temperature","authors":"Kai Wang ,&nbsp;Sheng Xu ,&nbsp;Jinming Zheng ,&nbsp;Shaolong Zhu ,&nbsp;Song Fang ,&nbsp;Hongmei Xiao ,&nbsp;Na Li ,&nbsp;Limin Qiu","doi":"10.1016/j.cryogenics.2025.104041","DOIUrl":"10.1016/j.cryogenics.2025.104041","url":null,"abstract":"<div><div>Ortho-para hydrogen conversion is a critical process in hydrogen liquefaction. However, comprehensive data and correlations on the ortho-para hydrogen conversion and pressure drop within catalyst packed beds across the typical range of Reynolds numbers encountered in converters/heat exchangers are still lacking. This study established an experimental setup to measure the catalytic conversion of ortho-para hydrogen and the associated pressure drop in tubular packed-bed converters in the liquid nitrogen temperature range. The effects of the particle size of iron oxide catalysts (20–80 mesh), space velocity (1.5–22 kg/(m³·s)), and packed-bed porosity (0.27–0.46) on the catalytic conversion of ortho-para hydrogen, along with the pressure drop characteristics, were examined at around 77 K and 2 MPa. A correlation was further developed for estimating the outlet concentration of para hydrogen with given space velocity, which would be useful for determining the catalyst dosage based on the targeted conversation rate in the product. Furthermore, by modifying the coefficients for viscous and inertial resistance on the basis of the Ergun equation, pressure drop correlations for packed-bed catalytic converters with different particle sizes were proposed, with remarkably improved predictive accuracy. This work offers critical prediction correlations for the design of ortho-para hydrogen catalytic converters/heat exchangers.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104041"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of the thermal expansion of bulk metallic glass in cryogenic temperature with a laser displacement method","authors":"Takashi Hirayama,&nbsp;Sojiro Uemura,&nbsp;Takaaki Morie","doi":"10.1016/j.cryogenics.2025.104037","DOIUrl":"10.1016/j.cryogenics.2025.104037","url":null,"abstract":"<div><div>The thermal expansion of structural components is a very important factor when designing cryogenic equipment such as cryocooler or superconducting equipment. However, conventional thermal expansion measurement systems require calibration of the sensor of the measurement system at cryogenic temperature, making measurement difficult. Therefore, in this study, we developed a new thermal expansion measurement system that can measure thermal expansion more conveniently than conventional measurement systems. Thermal expansion was measured using laser displacement units installed outside the vacuum vessel. Moreover, a conduction cooling system using a 4K-GM cryocooler was adopted for cooling. To confirm the effectiveness of the developed system, the thermal expansion of copper, a well-known material, was measured using this system, and the results were consistent with that of a previous study. The thermal expansion of bulk metallic glass, which is expected to be used in cryogenic environments, was measured using the developed system, and it was found to be -0.23% at cryogenic temperatures, smaller than that of other typical materials such as copper and aluminum.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104037"},"PeriodicalIF":1.8,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal conductivity and contraction of single and fifty-stacked 2G HTS tapes for the design of a superconducting fusion magnet","authors":"Tomoyuki Naito ,&nbsp;Tetsuhiro Obana ,&nbsp;Makoto Takayasu","doi":"10.1016/j.cryogenics.2025.104038","DOIUrl":"10.1016/j.cryogenics.2025.104038","url":null,"abstract":"<div><div>We measured the thermal conductivity, <span><math><mi>κ</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span>, of the single GdBa₂Cu₃O<span><math><msub><mrow></mrow><mrow><mn>7</mn><mo>−</mo><mi>δ</mi></mrow></msub></math></span> coated conductor (GdBCO-CC) tape and a bundled sample prepared by soldering fifty GdBCO-CC tapes, to design the thermal stability of a next high-temperature superconducting fusion magnet. A low-temperature peak for <span><math><mi>κ</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span> was observed for the single GdBCO-CC tape at 28.6 K. A simple heat-flow model for the layered sample demonstrated that the applied heat flowed mainly through the high purity metal such as the Cu and Ag-stabilizing layers. The <span><math><mi>κ</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span> of the bundled sample was similar to that of the single tape, suggesting that the contribution of the soldering layers to the heat flow was negligible and the <span><math><mi>κ</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span> of fifty or more bundled samples can be estimated using the <span><math><mi>κ</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span> of the single tape. We also measured the thermal contraction of the single tape along the length and of the fifty-stacked tape along the stacking direction, and then found that the stacking structure caused the large shrinkage along the stacking direction, which should be useful to optimize the structure of magnet at the operating low-temperature.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104038"},"PeriodicalIF":1.8,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143429965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Investigations on control strategies for multi-stage cold compressors in superfluid helium system","authors":"Huaiyu Chen ,&nbsp;Jin Shang ,&nbsp;Lei Yi ,&nbsp;Baohua Chao ,&nbsp;Sihao Liu ,&nbsp;Jinzhen Wang ,&nbsp;Cui Lv ,&nbsp;Jihao Wu","doi":"10.1016/j.cryogenics.2025.104039","DOIUrl":"10.1016/j.cryogenics.2025.104039","url":null,"abstract":"<div><div>As particle accelerator technology has advanced, there has been a growing demand for enhanced cooling capabilities, particularly within the superfluid helium temperature range. The integration of cold compressors has played a key role in minimizing the size of heat exchangers and optimizing cold exergy utilization. This paper presents a dynamic model of the superfluid helium system and its components, with validation achieved through a comparison between the model’s calculated results and experimental data obtained from a cold compressor test platform. To further reduce the costs associated with manual control, the study introduces and evaluates two novel control system designs. Additionally, it details the process of optimizing the performance of multi-stage serial centrifugal cold compressors, ensuring improved efficiency and reliability.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104039"},"PeriodicalIF":1.8,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction of a precise measuring probe based on tunnel diode oscillator","authors":"Zhihao Chen ,&nbsp;Haoran Wei ,&nbsp;Zhi Gang Cheng","doi":"10.1016/j.cryogenics.2025.104036","DOIUrl":"10.1016/j.cryogenics.2025.104036","url":null,"abstract":"<div><div>Metrology utilizing resonance techniques is a cornerstone for precise measurement of small signals. Resonances in mechanical oscillation, electric circuit, electromagnetic circuit, and optical cavity have been proven as powerful tools across a wide spectral range. In this study, we present the construction and characterization of a tunnel diode oscillator (TDO) circuit optimized for operating at cryogenic temperatures down to <span><math><mn>1.5</mn><mspace></mspace><mi>K</mi></math></span>. By taking advantage of the negative differential resistance (NDR) of a tunneling diode (TD), the TDO circuit is able to sustain a continuous oscillation. A quality factor of <span><math><mi>Q</mi><mo>≈</mo><mn>3.5</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>5</mn></mrow></msup></math></span> is achieved by careful optimization of the circuit's operating point, thus realizing sensitive detection of variations in inductance and capacitance. The TDO circuit is integrated to a cryostat insert and converted as a measuring probe for magnetic properties. We tested the probe by characterizing the superconducting transition of niobium. The evolution of magnetic penetration depth (<em>λ</em>) was measured with an uncertainty of around 0.2% across the transition in various magnetic field. Our results demonstrate the significant potential of TDO technique for cryogenic studies in physical sciences.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104036"},"PeriodicalIF":1.8,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143376654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experiments and simulations related to the sudden application of a heat pulse onto a supercritical helium flow","authors":"S. Shoala ,&nbsp;E. Ercolani ,&nbsp;F. Ayela ,&nbsp;J.M. Poncet","doi":"10.1016/j.cryogenics.2025.104029","DOIUrl":"10.1016/j.cryogenics.2025.104029","url":null,"abstract":"<div><div>Vacuum loss is a major accidental scenario in cryogenic facilities that use vacuum for thermal insulation from the surrounding environment. An experimental facility, called HELIOS, has been set up to study vacuum loss around a cryoline in which supercritical helium is flowing. Before carrying out real vacuum loss experiments, a preliminary test campaign was performed using an electrical test section inserted into a cryogenic loop within the HELIOS facility, at the exact location of the future vacuum loss test section. The electrical section is equipped with an electrical heater that was used to simulate the heat pulse that would be experienced by the supercritical helium flow in the event of a real vacuum loss accident. The consequences of the abruptly applied heat pulse have been studied, both in real and simulated conditions. The main objectives of this first experimental campaign are multiple: to assess the design of the HELIOS facility, verify the accuracy of the heat flux measurement methods, and use the results of the experimental test campaigns to improve the qualification of the thermal hydraulic code employed to size the experimental setup. The simulation was based on the thermal–hydraulic code CATHARE 3 and includes two-phases cryogenic flows. Thermal-hydraulic parameters of the supercritical helium flow as pressure, temperature and mass flow rate, have been recorded for several heat loads running from 0.45 kW to 2.5 kW, with durations of up to 2 min. Heat transfer in the supercritical loop and the liquid helium bath, as well as corresponding energy balances, have been calculated. The resulting estimations of the heat applied to the test section correspond with an excellent accuracy to the real thermal loads. For a heat flux of 1.35 kW, the data were also simulated with the CATHARE 3 code. The results of the simulation match the measured and calculated data with high accuracy. This preliminary work and its associated conclusions provide a firm basis for forthcoming experiments, which will be devoted to the study of heat transfer following a real breakdown of the insulating vacuum in the supercritical helium loop.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"147 ","pages":"Article 104029"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}