Intermetallics最新文献

{"title":"Simultaneous optimization of entropy changes and thermal hysteresis in barocaloric compound of Mn3Pt","authors":"Xueting Zhao ,&nbsp;Kun Zhang ,&nbsp;Peng Liu ,&nbsp;Qing Guo ,&nbsp;Haoyu Wang ,&nbsp;Yuanwen Feng ,&nbsp;Bing Li","doi":"10.1016/j.intermet.2024.108558","DOIUrl":"10.1016/j.intermet.2024.108558","url":null,"abstract":"<div><div>Mn₃Pt metal compounds are promising candidates for barocaloric cooling applications for their high thermal conductivity and pressure sensitivity. However, they are constrained by low entropy change and large thermal hysteresis. This study investigates the effects of doping with carbon (C) and nitrogen (N) and substituting with germanium (Ge) on the structure, as well as the thermal and barocaloric effects of Mn₃Pt. We found that N and C doping significantly reduces the phase transition temperature and improves pressure sensitivity, although at the cost of reduced entropy change. In contrast, Ge substitution increases the phase transition temperature and enhances the entropy change by 123 %, with Mn₃Pt_0.8Ge_0.2 achieving a maximum entropy change of 22.7 J kg⁻¹ K⁻¹. Additionally, defects were introduced to reduce the phase transition nucleation driving force, thereby lowering the thermal hysteresis to 4 K. This work provides a strategy for the simultaneous optimization of entropy change and thermal hysteresis, advancing the development of efficient and tunable barocaloric materials.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108558"},"PeriodicalIF":4.3,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high-strength self-propagating-brazed Al0.1CoCrFeNi joint at high temperatures with nano-multilayer foils composed of Ni/Al-Al-FeCo/CrNi filler metal","authors":"Baolei Wu ,&nbsp;Weiyuan Yu ,&nbsp;Wenqi Zhu ,&nbsp;Yang Li","doi":"10.1016/j.intermet.2024.108557","DOIUrl":"10.1016/j.intermet.2024.108557","url":null,"abstract":"<div><div>Novel nano-multilayer foils composed of Ni/Al-Al-FeCo/CrNi filler metals were developed for brazing Al_0.1CoCrFeNi alloys. These Ni/Al-FeCo/CrNi filler metals, designed using a high-entropy concept, were integrated to increase the mixing entropy and form solid solution structures. This strategic integration was aimed at preventing the formation of intermetallic compounds. The microstructural evolution and shear strength of the brazed joints were investigated by varying the holding time and brazing temperature. The results demonstrated the formation of a defect-free brazing joint, marked by the emergence of a solid solution structure resulting from the higher mixing entropy. With increasing temperature, the contribution of the solid-solution phase to the strengthening effect on the joint was more significant. The maximum shear strengths of the brazed joints were 308.5 MPa and 292.8 MPa at room temperature and 800 °C, respectively. Furthermore, the extended holding time and increased brazing temperature produced a steady increase in the shear strength of the joint with a corresponding transformation in the fracture mechanism from cleavage to ductility. This study introduces a novel process for brazing Al_0.1CoCrFeNi and offers a technological paradigm for manufacturing industry at a high temperature (800 °C).</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108557"},"PeriodicalIF":4.3,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Ce content and rolling route on the microstructure and mechanical properties of high-Zn content Al-Zn-Ce alloys","authors":"Z.L. Li ,&nbsp;C.Y. Liu","doi":"10.1016/j.intermet.2024.108559","DOIUrl":"10.1016/j.intermet.2024.108559","url":null,"abstract":"<div><div>In this study, Al-20 wt%Zn-x wt%Ce alloys (x = 0, 0.1, 0.5, and 1) were fabricated by casting, hot rolling, cold rolling, and solution treatment to investigate the effects of Ce content and rolling route on the microstructure and mechanical properties of high-Zn content Al-Zn-Ce alloys. Ce addition with weight ratio no higher than 0.5 % led to the formation of Al₂CeZn₂ phases in the Al-20Zn alloy, and the CeZn₃ phases were obtained in this alloy when the Ce content increased to 1 %. Rolling effectively disrupted the Ce-containing phases, and the presence of these phases changed the grain structure of the Al-Zn-Ce alloys by affecting their deformation mode during rolling. Dynamic precipitation of Zn phases occurred in the Al-20Zn alloys during rolling. However, the Ce-containing phase consumed a large amount of Zn atoms, and then inhibited the dynamic precipitation of Zn phases in the studied alloys. The alloys with 0.5 wt%Ce addition exhibited the best mechanical properties, and the strengthening mechanism of the Al-Zn-Ce alloys were studied.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108559"},"PeriodicalIF":4.3,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Initial oxidation behavior of AlCrMoNbTi high-entropy alloys studied by DFT calculations and experiments","authors":"Jinpeng Zhang,&nbsp;Qingyao Wu,&nbsp;Chuanlong Yang,&nbsp;Zhenhua Yang,&nbsp;Bingbing Yin,&nbsp;Yi Yang","doi":"10.1016/j.intermet.2024.108549","DOIUrl":"10.1016/j.intermet.2024.108549","url":null,"abstract":"<div><div>AlCrMoNbTi high entropy alloy (HEA) has the potential to be an excellent oxidation-resistant refractory high entropy alloy (RHEA) but has been limited by an undesirable oxide layer structure. In this work, the initial oxidation behavior of AlCrMoNbTi HEA was investigated by a combination of experiments and DFT calculations. The results indicate that O atoms tend to occupy the adsorption sites containing Ti atoms. Consequently, Ti atoms are more prone to combine with O atoms, resulting in the formation of compounds, which impedes the formation of protective oxides, such as Al₂O₃ and Cr₂O₃. Meanwhile, calculations indicate that Cr atoms can form stable Cr-O bonds in a Ti-rich environment, which can be exploited to improve oxidation resistance by modifying the Cr-rich oxide layer.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108549"},"PeriodicalIF":4.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of ultra-fine grain zone on mechanical properties of CuCrZr-Hastelloy X bimetallic structure manufactured by laser-directed energy deposition","authors":"Qian Liang,&nbsp;Yaqi Wang,&nbsp;Chendong Shao,&nbsp;Yueqiao Feng,&nbsp;Fenggui Lu","doi":"10.1016/j.intermet.2024.108550","DOIUrl":"10.1016/j.intermet.2024.108550","url":null,"abstract":"<div><div>In this study, CuCrZr-Hastelloy X bimetallic structure featuring an ultra-fine grain zone (UFGZ) near the interface were fabricated by laser-directed energy deposition (L-DED). Samples with UFGZ were obtained with 300 °C preheating, whereas samples without preheating did not contain UFGZ. The microstructures and mechanical properties of samples with and without UFGZ were compared. The formation of UFGZ was attributed to the presence of a spherical phase near the interface, which was identified as Ni (Fe, Cr, Mo). Due to the higher melting point of Hastelloy X compared to CuCrZr, Ni elements mixed into CuCrZr with the flow of the molten pool, solidified first, and served as substrates for the heterogeneous nucleation, ultimately promoting the formation of UFGZ. With 300 °C preheating, the hardness of CuCrZr near the interface increased from 115.07 HV to 148.51 HV due to the presence of UFGZ. And the hardness gap near the interface decreased from 172.58 HV to 147.19 HV, which improved the uniformity of mechanical properties. Moreover, the nanoindentation tests results that UFGZ increased the hardness of the zone near the interface from 1.42 GPa to 1.72 GPa. Tensile test results indicated that the UFGZ altered the fracture mode from brittle to ductile. Samples with UFGZ exhibited ductile fracture, while those without UFGZ exhibited brittle fracture. At room temperature, the tensile strength of samples with UFGZ increased from 298.44 MPa to 347.05 MPa. For tests conducted at 400 °C, the tensile strength increased from 165.12 MPa to 229.53 MPa. This enhancement indicated that UFGZ could improve the strength and toughness of the interface, thereby enhancing the interfacial bonding strength. This study is of great significance for improving the interfacial bonding strength of CuCrZr-Hastelloy X bimetallic structures.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108550"},"PeriodicalIF":4.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142592697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High temperature oxidation behavior of the dual-phase AlCoCr0.5Fe2.5Ni2.5 and single phase Al0.25CoCrFeNi high entropy alloys","authors":"Han Hu ,&nbsp;Fangjie Li ,&nbsp;Min Liu ,&nbsp;Dongye Yang ,&nbsp;Zongxin Zhu ,&nbsp;Qin Shen ,&nbsp;Zhigang Yu","doi":"10.1016/j.intermet.2024.108553","DOIUrl":"10.1016/j.intermet.2024.108553","url":null,"abstract":"<div><div>This study examined both theoretically and experimentally the oxidation behavior of AlCoCr_0.5Fe_2.5Ni_2.5 and Al_0.25CoCrFeNi alloys in the time for 10 h and 180 h at 800 °C in air atmosphere. The results showed that the weight gain of the dual-phase AlCoCr_0.5Fe_2.5Ni_2.5 alloy followed the parabolic rate law, while this value persisted almost unchanged for the single-phase Al_0.25CoCrFeNi alloy at the same oxidizing condition. Surface analysis of the oxide scale confirmed the formation of Al₂O₃, Cr₂O₃ and Fe₃O₄ oxides. Comparing the experimental results with thermodynamic models and Density functional theory (DFT) calculations suggests that Al and Cr are first oxidized in the AlCoCr_0.5Fe_2.5Ni_2.5 and Al_0.25CoCrFeNi alloys, respectively, then outer Fe₃O₄ scale appeared in the two alloys. The weak resistance to high temperature oxidation of AlCoCr_0.5Fe_2.5Ni_2.5 alloy was mainly ascribed to its high fraction of grain and phase boundaries, as well as the fragmented oxide layer formed due to enhanced element diffusion at the FCC/BCC phase boundaries. The element migration and oxidation process of oxide layers in the two alloys were declared based on thermodynamic and DFT calculations.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108553"},"PeriodicalIF":4.3,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystallochemistry, thermodynamic and physical properties of the intermetallic compound Cu3−x(As,Sb)","authors":"Marianne Mödlinger ,&nbsp;Alessia Provino ,&nbsp;Pavlo Solokha ,&nbsp;Serena De Negri ,&nbsp;Federico Caglieris ,&nbsp;Michele Ceccardi ,&nbsp;Cristina Bernini ,&nbsp;Pietro Manfrinetti","doi":"10.1016/j.intermet.2024.108526","DOIUrl":"10.1016/j.intermet.2024.108526","url":null,"abstract":"<div><div>During the investigation of the Cu-As-Sb ternary system, we identified the ternary intermetallic Cu_3−x(As,Sb) compound. Its crystal structure was solved and refined by single crystal and powder X-ray diffraction. While the binary Cu_3−xAs and Cu_3−xSb phases crystallize in the hexagonal Cu₃P-type (<em>hP</em>24, <em>P</em>6₃<em>cm</em>) and cubic anti-BiF₃-type (<em>cF</em>16, <em>Fm</em><span><math><mover><mn>3</mn><mo>¯</mo></mover></math></span><em>m</em>), respectively, Cu_3−x(As,Sb) adopts the cubic Cu₆AsSb prototype (<em>cP</em>32, <em>Pm</em><span><math><mrow><mover><mn>3</mn><mo>‾</mo></mover></mrow></math></span><em>n</em>). Crystallochemical reasons lead to the exclusion that its structure could be of the UH₃-type. Cu_3−x(As,Sb) is isotypic with Cu_12−xTeSb₃; their crystal structure is a stuffed ternary derivative of the Cr₃Si-type. SEM-EDX analyses reveal very large compositional ranges for this compound, mostly concerning the Sb/As ratio: 71.1−73.9 at.% Cu, 4.0−24.5 at.% As and 2.5−23.5 at.% Sb, corresponding to about Cu_2.5-2.8As_0.23-0.98Sb_0.23-0.92 (x = 0.2−0.5). The lattice parameter and, consequently, the unit cell volume regularly expand while increasing the Sb/As compositional ratio: <em>a</em> ≈ 7.47 Å for Cu_3−xAs_0.75Sb_0.25, <em>a</em> ≈ 7.65 Å for Cu_3−xAs_0.25Sb_0.75 (averaged values).</div><div>Cu_3−x(As,Sb) forms either by a peritectic reaction for As-rich compositions, or congruently for the equiatomic Sb/As and Sb-rich compositions. The decomposition- or melting-temperature values decrease as a function of the Sb/As compositional ratio [<em>e.g</em>. peritectic at 710 °C for Cu_3−xAs_0.75Sb_0.25 (Cu₇₂As₂₁Sb₇), congruent melting at 690 °C for Cu_3−xAs_0.50Sb_0.50 (Cu₇₂As₁₄Sb₁₄), and at 675 °C for Cu_3−xAs_0.25Sb_0.75 (Cu₇₂As₇Sb₂₁)].</div><div>Physical properties (electrical resistivity and magnetic susceptibility) indicate that Cu_3−x(As,Sb) behaves as a good metal with electrical resistivity decreasing as the Sb/As compositional ratio increases; a peculiar anomaly in the electrical resistivity behavior (heavy-fermions like) was observed at low temperature, the origin of which needs further investigation. The compound is a standard diamagnet.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108526"},"PeriodicalIF":4.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidation behavior and mechanical properties of a directionally solidified high Nb TiAl based alloy between 800 °C and 900 °C","authors":"Xuesong Xu ,&nbsp;He Liang ,&nbsp;Hongsheng Ding ,&nbsp;Karl P. Davidson ,&nbsp;R.V. Ramanujan ,&nbsp;Ruirun Chen ,&nbsp;Jingjie Guo ,&nbsp;Hengzhi Fu","doi":"10.1016/j.intermet.2024.108538","DOIUrl":"10.1016/j.intermet.2024.108538","url":null,"abstract":"<div><div>The high temperature oxidation behavior and mechanical property response of a directionally solidified Ti-46Al-7Nb-0.4W-0.6Cr-0.1B alloy were investigated. The ultimate tensile strength of the alloy at 800 °C, 850 °C and 900 °C are 647 MPa, 590 MPa and 508 MPa, respectively, and the tensile fracture mode changed from brittle cleavage fracture to micro-void accumulation ductile fracture. At lower temperatures Al₂O₃ forms first, growing along the γ lamellae to form oxide bands aligned with the lamellar orientation. The oxidation mass gain of the alloy after 900 °C/100 h isothermal oxidation is only 0.91 mg/cm². The oxidation kinetics results show the microalloyed high Nb TiAl alloy has excellent oxidation resistance, which is due to the formation of a TiO₂ layer containing Nb, Cr and W, the AlNb₂ phase and an Al/Cr rich transition layer above the directionally solidified lamellar matrix.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"176 ","pages":"Article 108538"},"PeriodicalIF":4.3,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the microstructure and properties of metastable β type Ti-8V4Mo3Cr3Zr3Al alloy with high strength and toughness","authors":"Xiang Gao ,&nbsp;Aili Tao ,&nbsp;Mingcong Zou ,&nbsp;Zaidong Xu","doi":"10.1016/j.intermet.2024.108547","DOIUrl":"10.1016/j.intermet.2024.108547","url":null,"abstract":"<div><div>In this paper, a new type of Ti-8V-4Mo-3Cr-3Zr-3Al metastable β-type titanium alloy is designed based on alloy design parameters such as valence electron concentration (VEC), <em>Bo</em>, and <em>Md</em>, and combines them with the empirical criterion of molybdenum equivalent fractionation. Optimize the microstructure of the alloy through processes such as cold rolling, annealing, and aging treatment to obtain good mechanical properties. The microstructure of cold rolling and post rolling heat treatment was observed and analyzed using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM), and the tensile properties of the alloy were tested. The characteristics of the alloy in terms of microstructure and properties were summarized and analyzed. The results show that the cold formability of the alloy after solid solution treatment is good, with a cold rolling reduction of over 85 %, and a large number of deformation twins generated during the cold rolling process. The yield strength after annealing and recrystallization is up to 1160 MPa, and elongation is 18.9 %. The final performance of the aged alloy is 1510 MPa for yield strength and 5 % for elongation.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108547"},"PeriodicalIF":4.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interfacial microstructure evolution and mechanical characterization of brazed Al2O3 joints with Ni‒Ti interlayer: An experimental and theoretical approach","authors":"Qi Zhang ,&nbsp;Kaihong Zheng ,&nbsp;Juan Wang ,&nbsp;Xianzhu Qin","doi":"10.1016/j.intermet.2024.108544","DOIUrl":"10.1016/j.intermet.2024.108544","url":null,"abstract":"<div><div>Reliable brazing joints of Al₂O₃ ceramics were obtained using an active Ni‒Ti interlayer under vacuum conditions. The interfacial microstructure and mechanical properties of the joints were studied. The structural, electronic, and elastic properties of the primary interfacial reaction phases were determined using first–principles calculations. After brazing at 1320 °C for 30 min, Ni₂Ti₄O layer and columnar AlNi₂Ti formed at the interface adjacent to the Al₂O₃ substrate. With increasing brazing temperature between 1300 °C and 1380 °C, Ni₂Ti₄O layer thickened gradually, and the AlNi₂Ti became increasingly longer. As brazing temperature reached 1400 °C, TiO was formed at the interface, and the Ni₂Ti₄O content decreased significantly; moreover, bulk AlNi₂Ti and TiNi₃ were distributed in the brazing seam. The highest shear strength of 129 MPa was achieved when brazed at 1350 °C for 30 min. According to the first–principles calculations, Ni₂Ti₄O is more readily formed than AlNi₂Ti, whereas AlNi₂Ti exhibits greater stability than Ni₂Ti₄O. Both AlNi₂Ti and Ni₂Ti₄O possess metallic bonds, contributing to the adhesion of the filler metal to the Al₂O₃ substrates. The calculated modulus and Poisson’s ratio indicate that both AlNi₂Ti and Ni₂Ti₄O exhibit ductile characteristics, which assist in relieving residual stress within the joint.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"175 ","pages":"Article 108544"},"PeriodicalIF":4.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}