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Effects of aging treatment on the microstructure and superelasticity of columnar-grained Cu71Al18Mn11 shape memory alloy

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International Journal of Minerals,Metallurgy and Materials 2016年第10期23卷 1157-1166页

作者： Ji-li Liu hai-you huang Jian-xin Xie Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Beijing 100083 China Department of Mechanics and Engineering Structure Wuhan University of Technology Wuhan 430070 China

The effect of aging treatment on the superelasticity and martensitic transformation critical stress in columnar-grained Cu_（71）Al_（18）Mn_（11） shape memory alloy（SMA） at the temperature ranging from 250°C to 400°C was investigated. The microstructure evolution during the aging treatment was characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The results show that the plate-like bainite precipitates distribute homogeneously within austenitic grains and at grain boundaries. The volume fraction of bainite increases with the increase in aging temperature and aging time, which substantially improves the martensitic transformation critical stress of the alloy, whereas the bainite only slightly affects the superelasticity. This behavior is attributed to a coherent relationship between the bainite and the austenite, as well as to the bainite and the martensite exhibiting the same crystal structure. The variations of the martensitic transformation critical stress and the superelasticity of columnar-grained Cu_（71）Al_（18）Mn_（11） SMA with aging-temperature and aging time are described by the Austin-Rickett equation, where the activation energy of bainite precipitation is 77.2 kJ ·mol1. Finally, a columnar-grained Cu_（71）Al_（18）Mn_（11） SMA with both excellent superelasticity（5%-9%） and high martensitic transformation critical stress（443-677 MPa） is obtained through the application of the appropriate aging treatments.

关键词： copper aluminum manganese alloys shape memory effect columnar grains aging bainite superelasticity

Effect of strain rate on the compressive deformation behaviors of lotus-type porous copper

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 687-695页

作者： Xin-hua Liu hai-you huang Jian-xin Xie Institute for advanced Materials and Technology University of Science and Technology Beijing Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology Beijing

Lotus-type porous copper was fabricated by unidirectional solidification, and compressive experiments were subsequently conducted in the strain rate range of 10-3-2400 s-1 with the compressive direction parallel to the pores. A GLEEBLE-1500 thermal-mechanical simulation system and a split Hopkinson pressure bar （SHPB） were used to investigate the effect of strain rate on the compressive deforma-tion behaviors of lotus-type porous copper. The influence mechanism of strain rate was also analyzed by the strain-controlling method and by high-speed photography. The results indicated that the stress-strain curves of lotus-typed porous copper consist of a linear elastic stage, a plateau stage, and a densification stage at various strain rates. At low strain rate （〈1.0 s^-1）, the strain rate had little influence on the stress-strain curves; but when the strain rate exceeded 1.0 s^-1, it was observed to strongly affect the plateau stage, showing obvious strain-rate-hardening characteristics. Strain rate also influenced the densification initial strain. The densification initial strain at high strain rate was less than that at low strain rate. No visible inhomogeneous deformation caused by shockwaves was observed in lotus-type porous copper during high-strain-rate deformation. However, at high strain rate, the bending deformation characteristics of the pore walls obviously differed from those at low strain rate, which was the main mechanism by which the plateau stress exhibited strain-rate sensitivity when the strain rate exceeded a certain value and exhibited less densification initial strain at high strain rate.

关键词： porous materials copper directional solidification strain rate sensitivity deformation modes stress-strain curves

Effect of compression direction on the dynamic recrystallization behavior of continuous columnar-grained CuNi10Fe1Mn alloy

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 851-859页

作者： Yong-kang Liu hai-you huang Jian-xin Xie Key Laboratory for Advanced Materials Processing of the Ministry of Education Institute of Advanced Materials and Technology University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation

The dynamic recrystallization（DRX） behavior of continuous columnar-grained（CCG） Cu Ni10Fe1 Mn alloy was investigated by hot compression along the solidification direction（SD） and perpendicular to the solidification direction（PD）. Specimens were compressed to a true strain of 0.8 at temperatures ranging from 25°C to 900°C and strain rates ranging from 0.01 to 10 s-1. The results indicate that DRX nucleation at grain boundaries（GBs） and DRX nucleation at slip bands（SBs） are the two main nucleation modes. For SD specimens, C-shaped bending and zig-zagging of the GBs occurred during hot compression, which made DRX nucleation at the GBs easier than that at the SBs. When ln Z ≤ 37.4（Z is the Zener–Hollomon parameter）, DRX can occur in SD specimens with a critical temperature for the DRX onset of;50°C and a thermal activated energy（Q） of 313.5 k J·mol-1. In contrast, in PD specimens, the GBs remained straight, and DRX nucleation occurred preferentially at the SBs. For PD specimens, the critical temperature is about 700°C, Q is 351.7 k J·mol-1, and the occurrence condition of DRX is ln Z ≤ 40.1. The zig-zagging of GB morphology can significantly reduce the nucleation energy at the GBs; as a result, DRX nucleation occurs more easily in SD specimens than in PD specimens.

关键词： copper–nickel alloys columnar grains compressive d

Numerical simulation of temperature field in horizontal core-filling continuous casting for copper cladding aluminum rods

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 684-692页

作者： Ya-jun Su Xin-hua Liu Yong-fu Wu hai-you huang Jian-xin Xie Key Laboratory for Advanced Materials Processing (Ministry of Education) Institute of Advanced Materials and Technology Uni- versity of Science and Technology Beijing

The steady-state temperature field of horizontal core-filling continuous casting （HCFC） for producing copper cladding aluminum rods was simulated by finite element method to investigate the effects of key processing parameters on the positions of solid-liquid interfaces （SLIs） of copper and aluminum. It is found that mandrel tube length and mean withdrawing speed have significant effects on the SLI positions of both copper and aluminum. Aluminum casting temperature （TAI）（1003-1123 K） and secondary cooling water flux （600-900 L.h-1） have little effect on the SLI of copper but cause the SLI of aluminum to move 2-4 mm. When TA1 is in a range of 1043-1123 K, the liquid aluminum can fill continuously into the pre-solidified copper tube. Based on the numerical simulation, reasonable processing parameters were determined.

关键词： metal cladding copper aluminum continuous casting interfaces computer simulation

Fine-tuning the ductile-brittle transition temperature of Mg_2Si intermetallic compound via Al doping

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 507-515页

作者： Ao Li Xin-peng Zhao hai-you huang Yuan Ma Lei Gao Yan-jing Su Ping Qian Institute for Advanced Materials and Technology University of Science and Technology Beijing Corrosion and Protection Center Key Laboratory for Environmental Fracture of Ministry of EducationUniversity of Science and Technology Beijing Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Department of Physics University of Science and Technology Beijing

Brittleness is a dominant issue that restricts potential applications of Mg_2Si intermetallic compounds(IMC). In this paper, guided by first-principles calculations, we found that Al doping will enhance the ductility of Mg_2Si. The underlying mechanism is that Al doping could reduce the electronic exchange effect between Mg and Si atoms, and increase the volume module/shear modulus ratio, both of which are beneficial to the deformation capability of Mg_2Si. Experimental investigations were then carried out to verify the calculation results with Al doping contents ranging from Al-free to 10 wt%. Results showed that the obtained ductile-brittle transition temperature of the Mg_2Si–Al alloy decreased and the corresponding ductility increased. Specifically, the ductile-brittle transition temperature could be reduced by about 100℃. When the content of Al reached 6 wt%, α-Al phase started to precipitate, and the ductile-brittle transition temperature of the alloy no longer decreased.

关键词： Mg alloy intermetallic compound first-principles calculations mechanical properties ductile-brittle transition temperature

Laparoscopic liver resection utilizing the ventral avascular area of the inferior vena cava:A retrospective cohort study

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World Journal of Gastroenterology 2025年第1期31卷 42-57页

作者： Kun huang Zhu Chen Heng Xiao hai-Yang Hu Xing-Yu Chen Cheng-you Du Xiang Lan Department of Hepatobiliary Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400000China Department of General Surgery Mianyang Hospital of Traditional Chinese MedicineMianyang 621000Sichuan ProvinceChina

BACKGROUND Laparoscopic liver resection(LLR)can be challenging due to the difficulty of establishing a retrohepatic tunnel under *** the third hepatic hilum before parenchymal transection often leads to significant liver mobilization,tumor compression,and bleeding from the short hepatic veins(SHVs).This study introduces a novel technique utilizing the ventral avascular area of the inferior vena cava(IVC),allowing SHVs to be addressed after parenchymal transection,thereby reducing surgical complexity and improving outcomes in in situ *** To introduce and evaluate a novel LLR technique using the ventral avascular area of the IVC and compare its short-term outcomes with conventional *** The clinical cohort data of patients with pathologically confirmed hepatocellular carcinoma or intrahepatic cholangiocarcinoma who underwent conventional LLR and novel LLR between July 2021 and July 2023 at the First Affiliated Hospital of Chongqing Medical University were retrospectively *** novel LLR,we initially separated the caudate lobe from the IVC using dissecting forceps along the ventral avascular area of the ***,we transected the parenchyma of the left and right caudate lobes from the caudal side to the cephalic side using the avascular area as a ***,we addressed the SHVs and finally dissected the root of the right hepatic vein or left hepatic *** short-term postoperative outcomes and oncological results of the two approaches were evaluated and *** A total of 256 patients were included,with 150(58.59%)undergoing conventional LLR and 106(41.41%)undergoing novel *** novel technique resulted in significantly larger tumor resections(6.47±2.96 cm vs 4.01±2.33 cm,P<0.001),shorter operative times(199.57±60.37 minutes vs 262.33±83.90 minutes,P<0.001),less intraoperative blood loss(206.92±37.09 mL vs 363.34±131.27 mL,P<0.001),and greater resection volume(345.11±31.40 mL vs 264.38±31.98 mL,P<0.001)comp

关键词： Laparoscopic liver resection Inferior vena cava Retrohepatic tunnel Short hepatic veins Complex liver tumors Intraoperative bleeding control

Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua Zhang Kailu Guo Lanyue Zhang Gening Du Hao you Junfeng huang Mudong Tu Hua Li Yong Peng Wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium（Rh@NiFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： NiFe-MIL-53 Rh Electrochemical reconstruction Catalytic mechanism Oxygen evolution reaction

Inhibiting SHP2 reduces glycolysis, promotes microglial M1 polarization, and alleviates secondary inflammation following spinal cord injury in a mouse model

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Neural Regeneration Research 2025年第3期20卷 858-872页

作者： Xintian Ding Chun Chen Heng Zhao Bin Dai Lei Ye Tao Song Shuai huang Jia Wang Tao you Department of Orthopedics The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Orthopedics Provincial Hospital Affiliated to Anhui Medical UniversityHefeiAnhui ProvinceChina

Reducing the secondary inflammatory response, which is partly mediated by microglia, is a key focus in the treatment of spinal cord injury. Src homology 2-containing protein tyrosine phosphatase 2(SHP2), encoded by PTPN11, is widely expressed in the human body and plays a role in inflammation through various mechanisms. Therefore, SHP2 is considered a potential target for the treatment of inflammation-related diseases. However, its role in secondary inflammation after spinal cord injury remains unclear. In this study, SHP2 was found to be abundantly expressed in microglia at the site of spinal cord injury. Inhibition of SHP2 expression using siRNA and SHP2 inhibitors attenuated the microglial inflammatory response in an in vitro lipopolysaccharide-induced model of inflammation. Notably, after treatment with SHP2 inhibitors, mice with spinal cord injury exhibited significantly improved hind limb locomotor function and reduced residual urine volume in the bladder. Subsequent in vitro experiments showed that, in microglia stimulated with lipopolysaccharide, inhibiting SHP2 expression promoted M2 polarization and inhibited M1 polarization. Finally, a co-culture experiment was conducted to assess the effect of microglia treated with SHP2 inhibitors on neuronal cells. The results demonstrated that inflammatory factors produced by microglia promoted neuronal apoptosis, while inhibiting SHP2 expression mitigated these effects. Collectively, our findings suggest that SHP2 enhances secondary inflammation and neuronal damage subsequent to spinal cord injury by modulating microglial phenotype. Therefore, inhibiting SHP2 alleviates the inflammatory response in mice with spinal cord injury and promotes functional recovery postinjury.

关键词： apoptosis glycolysis inflammatory response microglia neurons polarization spinal cord injury Src homology 2-containing protein tyrosine phosphatase 2

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan Zheng Qingming Lin Yan you Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin huang Jun Ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species