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Microstructure simulation of rapidly solidified ASP30 high-speed steel particles by gas atomization

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International Journal of Minerals,Metallurgy and Materials 2016年第3期23卷 294-302页

作者： jie Ma Bo Wang Zhi-liang Yang Guang-xin Wu jie-yu zhang Shun-li Zhao State Key Laboratory of Advanced Special Steel Shanghai University School of Materials Science and Engineering Shanghai University Research Institute Baoshan Iron & Steel Co. Ltd.

In this study, the microstructure evolution of rapidly solidified ASP30 high-speed steel particles was predicted using a simulation method based on the cellular automaton-finite element （CAFE） model. The dendritic growth kinetics, in view of the characteristics of ASP30 steel, were calculated and combined with macro heat transfer calculations by user-defined functions （UDFs） to simulate the microstructure of gas-atomized particles. The relationship among particle diameter, undercooling, and the convection heat transfer coefficient was also inves- tigated to provide cooling conditions for simulations. The simulated results indicated that a columnar grain microstructure was observed in small particles, whereas an equiaxed microstructure was observed in large particles. In addition, the morphologies and microstructures of gas-atomized ASP30 steel particles were also investigated experimentally using scanning electron microscopy （SEM）. The experimental re- suits showed that four major types ofmicrostructures were formed： dendritic, equiaxed, mixed, and multi-droplet microstructures. The simu- lated results and the available experimental data are in good agreement.

关键词： high-speed steel rapid solidification microstructure grain growth gas atomization

Combined fascia iliaca compartment block and monitored anesthesia care for geriatric patients with hip fracture: Two case reports

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World Journal of Clinical Cases 2021年第27期9卷 8268-8273页

作者： Li Zhan yu-jie zhang Jing-Xian Wang Department of Anesthesiology Lu’an Affiliated Hospital of Anhui Medical UniversityAnhui Medical UniversityLu’an 237005Anhui ProvinceChina

BACKGROUND Major hip surgery usually requires neuraxial or general anesthesia with tracheal intubation and may be supplemented with a nerve block to provide intraoperative and postoperative pain *** SUMMARY This report established that hip surgical procedures can be performed with a fascia iliaca compartment block(FICB)and monitored anesthesia care(MAC)while avoiding neuraxial or general *** was a preliminary experience with two geriatric patients with hip fracture,American Society of Anesthesiologists status III,and with many *** patient could be operated on within 48 h after *** general anesthesia and neuraxial anesthesia were high-risk procedures and had ***,we chose nerve block combined with a small amount of *** analgesia was provided by single-injection ultrasound-guided *** intravenous sedation was *** exposure was satisfactory,and neither patient complained of any symptoms during the *** This report showed that hip surgery for geriatric patients can be performed with FICB and MAC,although complications and contraindications are *** anesthetic program was accompanied by stable respiratory and circulatory system responses and satisfactory analgesia while avoiding the adverse effects and problems associated with either neuraxial or general anesthesia.

关键词： Fascia iliaca compartment block Monitored anesthesia care Geriatric Hip fracture Ultrasound-guided Case report

Numerical simulations of solidification and hot tearing for continuous casting of duplex stainless steel

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Journal of Iron and Steel Research International 2020年第6期27卷 643-655页

作者： Shan-shan Liu Liang Bai Bo Wang yu Yao Jun-kai Huang Zheng Chen jie-yu zhang State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200072China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Inner Mongolia Key Laboratory of Graphite and Graphene for Energy Storage and Coating Huhhot 010051Inner MongoliaChina Inner Mongolia University of Technology Huhhot 010051Inner MongoliaChina

Hot tearing is one of the major defects in continuous casting of steels, which severely limits the productivity of steelmaking processes. To further understand the defect, the problem of hot tearing in duplex stainless steel produced by a vertical continuous caster was investigated. A three-dimensional heat transfer and elastic-plastic model was developed based on the realistic roller layout in continuous slab casting, using ProCAST software. According to the hot tearing indicator criterion, the influence of operating parameters on the hot tearing susceptibility was evaluated. The results show that the surface temperature distribution is not sensitive to the superheat. The center of wide surface shell at the mold exit is the thinnest, and the thickness is about 10.52 mm at the superheat temperature of 40 -C. The hot tearing mainly concentrates on the slab solidification front and near the narrow face. However, corner cracks are prone to appear near the corner. With the increase in casting speed and the decrease in the cooling intensity in the secondary cooling zone, the solidification end point is rushed, which leads to the position of hot tearing lowering accordingly.

关键词： Hot tearing Duplex stainless steel Numerical simulation Solidification Continuous casting

Systematic and efficient GMPLS-based recovery mechanism with soft-protection using enhanced LMP

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 106-111页

作者： HUANG Shan-guo LI Bin DENG yu zhang jie GU Wan-yi Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

generalized multi-protocol label switching （GMPLS- based） protection and restoration technologies will play significant role in next-generation broadband IP network to ensure the survivability. In this article, a systematic GMPLS-based recovery mechanism is proposed using enhanced link management protocol （LMP）, which can support bidirectional fault notification relay more effectively. The major contributions and propositions in this article involve： 1） Soft-protection configuration for higher resource utilization with optimized routing; 2） Intelligent Shift from protection manner to restoration manner for the reduction of recovery latency; and 3） Toggleable revertive mode to increase restoration flexibility and to reduce loss of stability. Additionally, by leveraging valuable legacy including shared risk link group （SRLG） processing and fast reroute technique, the proposed recovery mechanism achieves higher resource utilization, fast and robust operation, satisfactory stability and flexibility, and is convenient in the apphcation over heterogeneous transport networks.

关键词： GMPLS LMP soft-protection bi-directional fault notification relay intelligent shift toggleable revertive mode

Development of a computational tool for materials design

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Advances in Manufacturing 2013年第2期1卷 123-129页

作者： Shuang-Lin Chen Wei-Sheng Cao Fan zhang Chuan zhang Jun Zhu jie-yu zhang School of Materials Science and Engineering Shanghai University CompuTherm LLC

An integrated modeling tool coupling thermo- dynamic calculation and kinetic simulation of multicom- ponent alloys is developed under the framework of integrated computational materials engineering. On the basis of PandatTM software for multicomponent phase diagram calculation, the new tool is designed in an inte- grated workspace and is targeted to understand the com- position-processing-structure-property relationships of multicomponent systems. In particular, the phase diagram calculation module is used to understand the phase stability under the given conditions. The calculated phase equilib- rium information, such as phase composition and chemical driving force, provides input for the kinetic simulation. In this paper, the design of the modeling tool will be pre- sented and the calculation examples from the different modules will also be demonstrated.

关键词： Phase diagram Materials design Ni alloy -Ti alloy - Diffusion simulation Precipitation simulation

First principles application for mechanical properties of Ti-doped W particles enhanced U matrix composite

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Rare Metals 2018年第9期37卷 815-822页

作者： Jian-Bo Qi Li-Li Ru Guang-Xin Wu jie-yu zhang Kuo-Chih Chou State Key Laboratory of Advanced Special Steel Shanghai University Institute of Metallurgy China North Nuclear Fuel Co. Ltd Department of Physical Chemistry University of Science and Technology Beijing

The stability, bonding, work of adhesion and electronic structure of the U/W interface with and without Ti were investigated by first principles to explore the me- chanical properties of W particles enhanced U-Ti alloy matrix composite as a construction material. The calculated results indicate that the preferable orientation of the U/W interfacial structure is （001）U/（110）w crystallographic plane, Ti atoms originating from U slab are prone to diffuse into W slab through the interface, and additional Ti in U matrix is the stronger adhesion to W, with an ideal work of adhesion of 6.93 J.m-2 for U-Ti/W interface, relative to the value of 6.72 J.m-2 for clean U/W interface. The stronger adhesion performance is due to the increase in valence electron hybridization for U-Ti/W compared with U/W interface, as evidenced by the characteristic of the local density of states for the interfacial atoms.

关键词： First principles U/W interface Diffuse Work of adhesion Electronic structure

Experimental Investigation on Viscosity of CaO-MgO(-Al_2O_3)-SiO_2 Slags and Solid-liquid Mixtures

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Journal of Iron and Steel Research International 2015年第12期22卷 1091-1097页

作者： Ji-fang XU Li-juan SU Dong CHEN jie-yu zhang Yao CHEN Shagang School of Iron and Steel Soochow University Shanghai Key Laboratory of Modern Metallurgy and Material Processing Shanghai University

The viscosities for the selected CaO-MgO-SiO2 and CaO-MgO Al2 O3-SiO2 slags were measured by rota- ting cylinder method in a wide temperature range from 1608 K to 1 823 K. The effects of temperature, slag basicity and Al2 O3 content were studied. The results indicated that the viscosity decreased with increasing the slag basicity at the same temperature. And the viscosities of the slag initially increased linearly with increasing Al2 O3 content in the slags and then decreased as the Al2 O3 content in the slags continued to increase. Al2 O3 addition has a more signifi- cant effect on the viscosity than slag basicity in the selected slags. Based on the experimental data and the fraction of solid phases calculated by the thermodynamic software, the effect of solid phases on slag viscosity was evaluated. The results indicated that the relationship between the relative viscosity and the volume fraction of solid phases esti- mated from the slag composition can be reasonable by allowing the inverse maximum fraction of solid particles to vary.

关键词： viscosity slag solid-liquid mixture model Al2 O3 content

Melatonin Alleviates Liver Fibrosis by Inhibiting Autophagy

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Current Medical Science 2022年第3期42卷 498-504页

作者： Lei jie Ru-tao HONG yu-jie zhang Lu-lin SHA Wei CHEN Xiao-fei REN Department of Gastroenterology First Affiliated Hospital of Anhui Medical UniversityKey Laboratory of Digestive Disease of Anhui ProvinceHefei 230022China Department of Critical Care Medicine of Cardiothoracic Surgery First Affiliated Hospital of Anhui Medical UniversityHefei 230022China

Objective Melatonin has been reported to suppress inflammation and alleviate liver fibrosis,but its effect on autophagy in liver fibrosis has not been *** study investigated the effect of melatonin on autophagy in an animal model of liver fibrosis and the hepatic stellate cell(HSC)-T6 cell *** The model was established in rats through carbon tetrachloride treatment,and melatonin was administered at three doses(2.5,5.0,and 10.0 mg/kg).Haematoxylin and eosin staining and Van Gieson’s staining were performed to examine the pathological changes of *** expression of alpha-smooth muscle actin(α-SMA)and Beclin1 in liver tissues was detected by immunohistochemical *** protein levels ofα-SMA,Beclin1 and LC3 in the animal model were detected by Western blot analysis,and gene levels of Beclin1 and LC3 were detected by quantitative real-time PCR(qRT-PCR)in the animal ***-T6 cells were activated by platelet-derived growth factor-BB(PDGF-BB).The expression ofα-SMA,Beclin1 and collagen I was detected by Western blot analysis,and the gene expression of Beclin1 and LC3 was detected by *** Melatonin reduced the expression ofα-SMA,Beclin1 and LC3 in liver *** addition,melatonin inhibited the activation of HSC-T6 cells and the expression ofα-SMA,Beclin1 and LC3 in these *** results revealed that melatonin could inhibit autophagy and HSC *** Melatonin might ameliorate liver fibrosis by regulating autophagy,suggesting that melatonin is a potential therapeutic agent for liver fibrosis.

关键词： autophagy liver fibrosis hepatic stellate cells melatonin

Scaphoid metastasis as the first sign of occult gastroesophageal junction cancer:A case report

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World Journal of Clinical Cases 2020年第7期8卷 1287-1294页

作者： yu-jie zhang Yan-Yan Wang Qi Yang Jian-Bing Li Department of Orthopedic Surgery The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina Department of Oncology Surgery The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina Department of Pathology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROUND Metastatic tumors of the hand are very *** are usually late manifestations of massive advanced ***,a small portion of acrometastases are indications of occult primary ***,we report an extremely rare case in which a scaphoid bone lesion was the initial manifestation and was found to be a metastasis from gastroesophageal junction(GEJ)*** SUMMARY A 57-year-old male patient presented with ongoing left wrist pain and swelling after *** was initially misdiagnosed with infection of the scaphoid bone and treated with antibiotics and anti-inflammatory *** radiographic investigations showed a scaphoid pathological fracture,indicating a metastatic tumor derived from the GEJ and/or right lung *** failed to identify the pathology of the mass at the GEJ,which grew in an exophytic pattern.A lung puncture biopsy was not performed because the patient refused the *** relieve his wrist pain and obtain a definite pathology,we resected the scaphoid *** on the clinical and pathological results,the patient was finally diagnosed with multiple metastases of advanced GEJ *** underwent chemotherapy and died 6 mo after his initial *** Despite the rareness of the disease,orthopedic surgeons should consider the possibility of metastasis to the bones of the hand when patients complain of persistent and progressive pain in the hand.

关键词： Hand metastasis Scaphoid Gastroesophageal junction cancer Diagnosis Case report