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First principles study of stability, mechanical, and electronic properties of chromium silicides

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Chinese Physics B 2018年第10期27卷 548-557页

作者： bo ren De-hong Lu Rong Zhou De-Peng Ji Ming-Yu Hu Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Through the first principles calculations, the chemical stability, mechanical, and electronic properties of chromium silicides are predicted. Estimating enthalpies and binding energies, density state density and electron density distribution are combined to analyse the thermodynamic stability and physical properties of chrome-silicon binary compounds. The chromium silicide includes Cr3 Si, Cr5 Si3, CrSi, and CrSi2. The chemical stability and the information about electronic structure, mechanical properties, Debye temperature, and anisotropy properties are obtained by density functional theory and Debye quasi-harmonic approximation. Meanwhile, the calculation of elastic modulus shows that Cr3 Si has the highest body modulus value（251 GPa） and CrSi2 possesses the highest shear modulus（169.5 GPa） and Young＇s modulus（394.9 GPa）. In addition, the Debye temperature and the speed of sound of these Cr–Si compounds are also *** the calculated bulk modulus is different from Young＇s modulus anisotropy index, and also different from Young＇s modulus of a three-dimensional surface shape, the different mechanical anisotropies of all the compounds are obtained.

关键词： density functional theory electronic structures mechanical properties anisotropy

Constitutive Modeling for Thixoforming of 9Cr18 Semi-solid Alloy and 3D Forecast Mapping

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Journal of Iron and Steel Research International 2016年第12期23卷 1309-1315页

作者： Ya-ping LI ren-bo SONG Yong-jin WANG School of Materials Science and Engineering University of Science and Technology Beijing

Thixotropic Compression tests were carried out on 9Cr18 semi-solid alloy through Gleeble-1500 thermal simulation machine. According to the experiment analysis, macro separation occurred during thixoforming. The liquid film was extruded outside to the surface and solidified to form eutectic structure. The solid particles were connected with each other and underwent plastic deformation. According to the comparison between Zhou-Guan model and modified Zhou-Guan model, it could be observed that the adding of thixotropic factor played an important role in the regression and the latter one was more credible. The modified Zhou-Guan model could well describe the thixoforming behavior. 3D forecast mapping was built for 9Cr18 semi solid alloy in thixoforming temperature range. It would provide valuable information for selecting process parameters during thixoforming in the manufacture process.

关键词： thixoforming constitutive model liquid fraction thixotropic factor 3D forecast

Formation mechanism of interfacial microstructures and mechanical properties of Ti2AlNb/Ni-based superalloy joints brazed with NiCrFeSiB filler metal

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Progress in Natural Science:Materials International 2021年第2期31卷 310-318页

作者： Haishui ren Xinyu ren Weimin Long bo Chen Shujie Pang Huaping Xiong Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials State Key Laboratory of Advanced Brazing Filler Metals and Technology Zhengzhou Research Institute of Mechanical Engineering Department of Material Science and Engineering Beihang University

Dissimilar brazing of Ti2AlNb-based alloy and Ni-based wrought superalloy（GH536） was studied using NiCrFeSiB filler metal. The Ti2AlNb/GH536 joints were analyzed by scanning electron microscope（SEM） equipped with an electron probe micro-analyzer（EPMA）, X-ray diffraction（XRD） and transmission electron microscopy（TEM）. The formation mechanism of interfacial microstructure and mechanical properties of Ti2AlNb/GH536 joints were studied. The results indicated that Ti2Ni（Al,Nb）, AlNi2Ti and TiB2reaction layers were formed in the joint adjacent to Ti2AlNb base metal. These layers resulted in high micro-hardness and the weak link of the joint. γ solid solution was formed through isothermal solidification and β1-Ni3Si phase precipitated in the γ solid solution during cooling process. Ni3B, β1-Ni3Si and CrB phases appeared in the centre of the joint. Blocky and needle-like borides formed within the diffusion affected zone of GH536 base alloy. The maximum tensile strength of Ti2AlNb/GH536 joints reached 425 MPa at room temperature and the strength value of 373 MPa was maintained at 923 K.

关键词： Ti 2 AlNb alloy Ni-based superally Brazing Microstructure Mechanical properties

Risk factors for residual tumor after resection of hepatocellular carcinoma

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World Journal of Gastroenterology 2011年第14期17卷 1889-1894页

作者： Xiao-hong Chen bo-Heng Zhang Yin Xin Zheng-Gang ren Jia Fan Shuang-Jian Qiu Jian Zhou Liver Cancer Institute and Zhongshan Hospital Fudan University Shanghai 20032 China

AIM:To identify the clinicopathological risk factors correlated with residual tumor in hepatocellular carcinoma (HCC) patients after resection. METHODS:From January 2001 to April 2007,766 HCC patients who had undergone resection were included in this research. Lipiodol angiography was performed within 2 mo after surgery and followed by post-Lipiodol computed tomography (CT) 4 wk later for all 766 patients to monitor tumor in the remnant liver. Tumor detected within the first 3-mo postoperative period was defined as residual tumor. Patients were divided into 2 groups:disease or disease-free within the first 3 mo after surgery. Risk factors for residual tumor were investigated among various clinicopathological variables. RESULTS:A total of 63 (8.22%) patients were found to have residual tumor after surgery. Three independent factors associated with residual tumor were identified by multivariate analysis:preoperative serum α-fetoprotein (AFP) level [odds ratio (OR) = 1.68 (95% confidence interval (CI):1.20-2.36)],tumor size [OR = 1.73 (95% CI:1.29-2.31)] and microvascular invasion [OR = 1.91 (95% CI:1.12-3.24)]. CONCLUSION:Residual tumor is related to AFP level,tumor size and microvascular invasion. Patients at high risk should undergo closer follow-up and could be candidates for multimodality therapy.

关键词： Risk factors Residual tumor Hepatocellular carcinoma Radical resection Lipiodol angiography

Hot ductility behavior of a Fe-0.3C-9Mn-2Al medium Mn steel

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 422-429页

作者： Yong-jin Wang Shuai Zhao ren-bo Song Bin Hu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The hot ductility of a Fe-0.3C-9Mn-2Al medium Mn steel was investigated using a Gleeble3800 thermo-mechanical *** tensile tests were conducted at different temperatures(600-1300℃)under a constant strain rate of 4×10^(−3)s^(−1).The fracture behavior and mechanism of hot ductility evolution were *** showed that the hot ductility decreased as the temperature was decreased from 1000℃.The reduction of area(RA)decreased rapidly in the specimens tested below 700℃,whereas that in the specimen tested at 650℃was lower than 65%.Mixed brittle-ductile fracture feature is reflected by the coexistence of cleavage step,intergranular facet,and dimple at the *** fracture belonged to ductile failure in the specimens tested between 720-1000℃.Large and deep dimples could delay crack *** change in average width of the dimples was in positive proportion with the change in *** wide austenite-ferrite intercritical temperature range was crucial for the hot ductility of medium Mn *** formation of ferrite film on austenite grain boundaries led to strain *** point elongation occurred at the austenite-ferrite intercritical temperature range during the hot tensile test.

关键词： medium Mn steel hot ductility reduction of area fracture behavior microstructure characterization

MJO ensemble prediction in BCC-CSM1.1(m)using different initialization schemes

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Atmospheric and Oceanic Science Letters 2016年第1期9卷 60-65页

作者： ren hong-Li Wu Jie Zhao Chong-bo Cheng Yan-Jie Liu Xiang-Wen Laboratory for Climate Studies National Climate CenterChina Meteorological Administration

The Madden–Julian Oscillation（MJO）is a dominant mode of tropical intraseasonal variability（ISV）and has prominent impacts on the climate of the tropics and *** the MJO using fully coupled climate system models is an interesting and important *** paper reports upon a recent progress in MJO ensemble prediction using the climate system model of the Beijing Climate Center,BCC-CSM1.1（m）;specifically,the development of three different initialization schemes in the BCC ISV/MJO prediction system,*** sets of 10-yr hindcasts were separately conducted with the three initialization *** results showed that the IMPRESS is able to usefully predict the MJO,but is sensitive to the initialization scheme used and becomes better with the initialization of *** addition,a new ensemble approach was developed by averaging the predictions generated from the different initialization schemes,helping to address the uncertainty in the initial values of the *** ensemble-mean MJO prediction showed significant improvement,with a valid prediction length of about 20 days in terms of the different criteria,i.e.,a correlation score beyond 0.5,a RMSE lower than 1.414,or a mean square skill score beyond *** study indicates that utilizing the different initialization schemes of this climate model may be an efficient approach when forming ensemble predictions of the MJO.

关键词： MJO initialization scheme ensemble prediction climate model

Effect of infiltrating time on interfacial reaction and properties of tungsten particles reinforced Zr-based bulk metallic glass composites

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China Foundry 2020年第4期17卷 253-259页

作者： Qing-chun Xiang Zhi-bo Feng Wei Zhang hong-ding Wang Ying-lei ren Ke-qiang Qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The tungsten particles reinforced Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vit 1 alloy) bulk metallic glass composites (BMGCs) were prepared by the melt infiltrating casting method with the infiltrating time of 1, 5 and 10 min, respectively. The changes of interfacial reaction and compression properties of the bulk metallic glass composites with different infiltrating times were studied. Results show that with the increase of infiltrating time, tiny nanocrystals are generated at the interfacial boundary of tungsten particles and the amorphous matrix, and the size of tiny crystals increases with the infiltrating time. When the infiltrating time is 10 min, polygonal crystals with a larger size are also generated within the amorphous matrix. The compressive strength of the composites also increases with the infiltrating time. When the infiltrating time is 10 min, the compressive strength of the composite reaches 2,030 MPa and the compression strain is 44%. The fracture morphology of the composite materials is in a vein-like pattern and the melting phenomenon is found on the fracture surface. In addition, the density of the shear bands during the compressive tests of the composite materials increases with the infiltrating time.

关键词： Zr-based metallic glass infiltrating time interfacial reaction shear bands compressive strength

Prognostic significance of systemic immune-inflammation index in patients with intrahepatic cholangiocarcinoma undergoing hepatic resection

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World Journal of Gastrointestinal Oncology 2020年第4期12卷 467-482页

作者： Hui Li Jin-Ju Wang Min Zhang bo ren Jia-Xin Li Lin Xu hong Wu Department of Liver Surgery and Liver Transplantation West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina State Key Laboratory of Biotherapy and Cancer Center Sichuan UniversityChengdu 610041Sichuan ProvinceChina Collaborative Innovation Center of Biotherapy Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Anesthesiology Jiulongpo People’s HospitalChongqing 400000China

BACKGROUND The prognosis of intrahepatic cholangiocarcinoma(ICC)patients following surgical resection remains *** is necessary to investigate effective biomarkers or prognostic models for ICC *** To investigate the prognostic effect of systemic immune-inflammation index(SII)to predict long-term outcomes in ICC patients with undergoing hepatic *** Consecutive ICC patients who underwent initial hepatectomy with curative intent from January 2009 to September 2017 were retrospectively ***-operating characteristic(ROC)curves were used to determine the optimal cut-off values of ***-Meier curves and Cox proportional hazards regression were performed to evaluate the discriminative ability of preoperative SII in predicting overall survival(OS)and recurrence-free survival(RFS).RESULTS A total of 530 patients were included and randomly divided into derivation(n=265)and validation cohort(n=265).The optimal cut-off value for SII was *** median follow-up of 18 mo(range,1-115.4 mo),317(59.8%)patients died and381(71.9%)patients experienced tumor *** SII level was associated with better OS and RFS(both P<0.05).Multivariate analyses identified multiple tumors,node invasion and high SII level as independent risk factors for OS,while multiple tumors,node invasion and high SII level were identified as independent risk factors for *** cohort confirmed the findings of derivation *** The present study demonstrated the feasibility of preoperative SII as a prognostic indicator for *** with increased SII level were associated with worse OS and earlier tumor *** SII level was an independent risk factor for OS and RFS in patients with ICC after *** the future,the SII could help stratifying patients with ICC,thus guiding therapeutic choices,especially in immunotherapy.

关键词： Intrahepatic cholangiocarcinoma Systemic immune-inflammation index Hepatectomy Prognostic predictor Long-term outcomes Immunotherapy

Retraction Note: Construction of Gpm6a/ReelinGFPCreERT2 by BAC recombination using a specific gene in hepatic mesothelial or stellate cells

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World Journal of Gastroenterology 2019年第25期25卷 3281-3282页

作者： hong-bo Shi Jin-Li Lou hong-Lin Shi Feng ren Yu Chen Zhong-Ping Duan Beijing Institute of Hepatology Beijing Youan HospitalCapital Medical UniversityBeijing 100069China Clinical Laboratory Center Beijing Youan HospitalCapital Medical UniversityBeijing 100069China Artificial Liver Center Beijing Youan HospitalCapital Medical UniversityBeijing 100069China

We have decided to retract the above article for further consideration due to some misunderstandings in communication.

关键词： Retraction note