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Fabrication of high nitrogen austenitic stainless steels with excellent mechanical and pitting corrosion properties

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 387-392页

作者： Hua-bing li Zhou-hua jiang Yang Cao Zu-rui Zhang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

A series of high nitrogen austenitic stainless steels were successfully developed with a pressurized electroslag remelting furnace. Nitride additives and deoxidizer were packed into the stainless steel pipes, and then the stainless steel pipes were welded on the surface of an electrode with low nitrogen content to prepare a compound electrode. Using Si3N4 as a nitrogen alloying source, the silicon contents in the ingots were prone to be out of the specification range, the electric current fluctuated greatly and the surface qualities of the ingots were poor. The surface qualities of the ingots were improved with FeCrN as a nitrogen alloying source. The sound and compact macrostructure ingot with the maximum nitrogen content of 1.21wt% can be obtained. The 18Cr18Mn2Mo0.9N high nitrogen austenitic stainless steel exhibits high strength and good ductility at room temperature. The steel shows typical ductile-brittle transition behavior and excellent pitting corrosion resistance properties.

关键词： high nitrogen austenitic stainless steels electroslag remelting nitrogen alloying ductile-brittle transition pitting corrosion resistance

Intergranular corrosion behavior of high nitrogen austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 654-660页

作者： Hua-bing li Zhou-hua jiang Zu-rui Zhang Yang Cao Yan Yang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

The intergranular corrosion （IGC） behavior of high nitrogen austenitic stainless steel （HNSS） sensitization treated at 650-950℃ was investigated by the double loop electrochemical potentiodynamic reactivation （DL-EPR） method. The effects of the electrolytes, scan rate, sensitizing temperature on the susceptibility to IGC of HNSS were examined. The results show that the addi-tion of NaCl is an effective way to improve the formation of the cracking of a passive film in chromium-depleted zones during the reactivation scan. Decreasing the scan rate exhibits an obvious effect on the breakdown of the passive film. A solution with 2 mol/L H2SO4＋1 mol/L NaCl＋0.01 mol/L KSCN is suitable to check the susceptibility to IGC of HNSS at a sensitizing temperature of 650-950℃ at a suitable scan rate of 1.667 mV/s. Chromium depletion of HNSS is attributed to the precipitation of Cr2N which results in the susceptibility to IGC. The synergistic effect of Mo and N is suggested to play an important role in stabilizing the passive film to prevent the attack of IGC.

关键词： intergranular corrosion high nitrogen austenitic stainless steel sensitization passive film chromium depletion

Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 517-524页

作者： Hua-bing li Zhou-hua jiang Yan Yang Yang Cao Zu-rui Zhang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

Pitting corrosion and crevice corrosion behaviors of high nitrogen austenitic stainless steels （HNSS） were investigated by electrochemical and immersion testing methods in chloride solution, respectively. The chemical constitution and composition in the depth of passive films formed on HNSS were analyzed by X-ray photoelectron spectrum （XPS）. HNSS has excellent pitting and crevice corrosion resistance compared to 316L stainless steel. With increasing the nitrogen content in steels, pitting potentials and critical pitting temperature （CPT） increase, and the maximum, average pit depths and average weight loss decrease. The CPT of HNSS is correlated with the alloying element content through the measure of alloying for resistance to corrosion （MARC）. The MARC can be expressed as an equation of CPT=2.55MARC-29. XPS results show that HNSS exhibiting excellent corrosion resistance is attributed to the enrichment of nitrogen on the surface of passive films, which forms ammonium ions increasing the local pH value and facilitating repassivation, and the synergistic effects of molybdenum and nitrogen.

关键词： high nitrogen austenitic stainless steel pitting corrosion crevice corrosion nitrogen critical pitting temperature syner-gistic effect

Clustering-triggered Emission of Cellulose and Its Derivatives

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Chinese Journal of Polymer Science 2019年第4期37卷 409-415,I0007页

作者： lin-lin Du bing-li jiang Xiao-Hong Chen Yun-Zhong Wang lin-Min Zou Yuan-li liu Yong-Yang Gong Chun Wei Wang-Zhang Yuan Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Ministry of EducationCollege of Materials Science and EngineeringGuilin University of Technology College of Pharmacy Guilin Medical University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University

In recent years, nonconventional luminogens free of aromatic groups have attracted extensive attention due to their academic importance and promising wide applications. Whilst previous studies generally focused on fluorescence from aliphatic amine or carbonylcontaining systems, less attention has been paid to room temperature phosphorescence(RTP) and the systems with predominant oxygen functionalities. In this work, photophysical properties of the polyhydroxy polymers, including microcrystalline cellulose(MCC), 2-hydroxyethyl cellulose(HEC), hydroxypropyl cellulose(HPC), and cellulose acetate(CA), were studied and compared. While MCC,HEC, and HPC solids showed bright emission alongside distinct RTP, CA demonstrated relatively low intensity of solid emission without noticeable RTP. Their emissions were explained in terms of the clustering-triggered emission(CTE) mechanism and conformation rigidification. Additionally, on account of its intrinsic emission, concentrated HEC aqueous solution could be used as the probe for the detection of 2,4,6-trinitrophenol(TNP).

关键词： Cellulose Nonconventional luminogens Room temperature phosphorescent Clustering-triggered emission

Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research International 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu Zhou-hua jiang Hua-bing li Rui Zhang Hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time

Vinyltrimethylsilane as a novel electrolyte additive for improving interfacial stability of li-rich cathode working in high voltage

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Chinese Chemical Letters 2024年第2期35卷 534-538页

作者： bing jiang Hao li Bi Luo Lehao liu lihua Chu Qiaobao Zhang Meicheng li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of New EnergyNorth China Electric Power UniversityBeijing 102206China State Key Laboratory of Physical Chemistry of Solid Surfaces College of MaterialsXiamen UniversityXiamen 361005China

Boosting the interfacial stability between electrolyte and li-rich cathode material at high operating voltage is vital important to enhance the cycling stability of li-rich cathode materials for high-performance li-ion *** this work,vinyltrimethylsilane as a new type of organic silicon electrolyte additive is studied to address the interfacial instability of li-rich cathode material at high operating *** cells using vinyltrimethylsilane additive shows the high capacity retention of 73.9%after 300 cycles at 1 C,whereas the cells without this kind of additive only have the capacity retention of 58.9%.The improvement of stability is mainly attributed to the additive helping to form a more stable surface film for li-rich cathode material,thus avoiding direct contact between the electrolyte and the cathode material,slowing down the dissolution of metal ions and the decomposition of the electrolyte under high operating *** findings in this work shed some light on the design of stable cycling performance of li-rich cathode toward advanced li-ion batteries.

关键词： Vinyltrimethylsilane Electrolyte additive li-rich cathode Interfacial stability Capacity retention

High-Performance Anion Exchange Membrane Fuel Cells Enabled by Nitrogen Configuration Optimization in Graphene-Coated Nickel for Enhanced Hydrogen Oxidation

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Energy & Environmental Materials 2024年第5期7卷 345-352页

作者： Pan li jiang Zhong Yanqing Fu Zhentao Du Lan jiang Yi Han Jan Luxa bing Wu Zdenek Sofer Qiliang Wei Weiyou Yang School of Resources Environment and Materials State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi University Institute of Micro/Nano Materials and Devices Ningbo University of Technology Department of Inorganic Chemistry University of Chemistry and Technology Prague

Anion exchange membrane fuel cell （AEMFC） technology is attracting intensive attention,due to its great potential by using non-precious-metal catalysts （NPMCs） in the cathode and cheap bipolar plate materials in alkaline ***,in such case,the kinetics of hydrogen oxidation reaction （HOR） in the anode is two orders of magnitude sluggish than that of acidic electrolytes,which is recognized as the grand challenge in this ***,we report the rationally designed Ni nanoparticles encapsulated by N-doped graphene layers （Ni@NG） using a facile pyrolysis *** on the density functional theory calculations and electrochemical performance analysis,it is witnessed that the rich Pyridinic-N within the graphene shell optimizes the binding energy of the intermediates,thus enabling the fundamentally enhanced activity for HOR with robust *** a proof of concept,the resultant Ni@NG sample as the anode with a low loading(1.8 mg cm-2) in AEMFCs delivers a high peak power density of500 mW cm-2,outperforming all of those of NPMC-based analogs ever reported.

关键词： anion-exchange-membrane fuel cells density functional calculations hydrogen oxidation reaction Ni-based non-precious-metal catalysts pyridinic N-doped graphene

Upadacitinib for refractory ulcerative colitis with primary nonresponse to infliximab and vedolizumab:A case report

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World Journal of Clinical Cases 2024年第9期12卷 1685-1690页

作者： Xuan Xu Jing-Wen jiang bing-Yun Lu Xia-Xi li Department of Gastroenterology Shenzhen HospitalSouthern Medical UniversityShenzhen 518100Guangdong ProvinceChina The First Clinical Medical School Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

BACKGROUND Many patients with ulcerative colitis(UC)do not respond well to,or tolerate conventional and biological *** is currently no consensus on the treatment of refractory *** have demonstrated that the selective Janus kinase 1 inhibitor upadacitinib,a small-molecule drug,is effective and safe for treating ***,no studies have revealed that upadacitinib is effective in treating refractory UC with primary nonresponse to infliximab and *** SUMMARY We report the case of a 44-year-old male patient with a chief complaint of bloody diarrhoea with mucus and pus,in addition to *** patient had recurrent disease after receiving mesalazine,prednisone,azathioprine,infliximab and vedolizumab over four *** on the endoscopic findings and pathological biopsy,the patient was diagnosed with refractory *** particular,the patient showed primary nonresponse to infliximab and *** on the patient’s history and recurrent disease,we decided to administer *** hospitalisation,the patient was received upadacitinib under our *** weeks after the initiation of upadacitinib treatment,the patient’s symptoms and endoscopic findings improved *** notable adverse reactions have been reported to *** Our case report suggests that upadacitinib may represent a valuable strategy for treating refractory UC with primary nonresponse.

关键词： Upadacitinib Refractory ulcerative colitis Primary nonresponse Infliximab Vedolizumab Case report

Heat Transfer and Friction Characteristics of Printed Circuit Heat Exchangers with Different Channel Structures for S-CO_(2) Power System

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Journal of Thermal Science 2024年第3期33卷 1132-1147页

作者： jiang Tao li Mingjia Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Printed circuit heat exchanger(PCHE)has been widely used in supercritical carbon dioxide(S-CO_(2))power systems because of its high heat transfer efficiency and good ***,due to the large variety of PCHE configurations,channel selection in practical applications lacks a ***,this paper discussed the heat transfer and friction characteristics and the synergy of three fields in the channel under the guidance of the field synergy principle for four typical PCHE ***,the comprehensive performance of four channels was ***,the heat transfer and friction factor correlations for S-CO_(2)in four channels were *** findings demonstrate that the synergy of velocity and pressure fields of the straight channel PCHE is better(β≈180°),so its resistance loss is relatively *** zigzag and sinusoidal wavy channels and the airfoil fins can reduce the angle a between the temperature gradient and velocity,thus enhancing the heat *** sinusoidal wavy channel can reduce flow resistance compared to the zigzag channel due to the rounded *** streamlined airfoil structure can guide the flow and reduce backflow,thus reducing resistance *** the range of Re studied in this paper,the maximum error of the proposed heat transfer and friction factor correlations of PCHE is 7.0%,which shows good fitting *** research in this paper can provide a reference for the selection and design of PCHE with different channel configurations.

关键词： printed circuit heat exchanger supercritical carbon dioxide typical channel structure field synergy analysis