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Iron-handling solute carrier SLC22A17 as a blood-brain barrier target after stroke

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Neural Regeneration research 2025年第11期20卷 3207-3208页

作者： Xueqi Ren Wenlu Li Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Neuroprotection research laboratories Departments of Radiology and NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

The pathophysiology of ischemic stroke is complex and multifactorial,involving various forms of cell death such as apoptosis,autophagy,and necrosis.A recent study suggests that oxidative and inflammatory stress can induce ferroptosis,a specialized form of cell death characterized by the accumulation of lipid peroxides dependent on intracellular iron overload(Li and Jia,2023).

关键词： death specialized barrier

Strengthening effect of Cu-rich phase precipitation in 18Cr9Ni3CuNbN austenitic heat-resisting steel

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 141-147页

作者： Chengyu CHI Hongyao YU Jianxin DONG Xishan XIE Zhengqiang CUI Xiaofang CHEN Fusheng LIN High Temperature materials research laboratories School of Materials Science and EngineeringUniversity of Science and Technology Beijing Beijing 100083 China Shanghai Power Equipment research Institute Shanghai 200240 China

The Cu-containing austenitic heat-resistant steel 18Cr9Ni3CuNbN, which is being used as superheater and reheater tube material for modern ultra-super-critical （USC） power plants all over the world, has been investigated at 650 ℃ long time aging till 10 000 h. SEM, TEM and 3DAP （three dimensional atom probe） have been used to follow microstructural changes with mechanical property variations. Experimental results show that Cu-rich phase and MX precipitate in the grains as well as M 23 C 6 precipitates at grain boundaries are the main precipitation strengthening phases in this steel. Among them Cu-rich phase is the most important strengthening phase. Homogeneous distribution of very fine nano-size Cu-rich phase has been formed at very early stage of 650 ℃ aging （less than 1 h）. Cu atoms gradually concentrate to Cu-rich particles and the other elements （such as Fe, Cr, Ni etc） diffuse away from Curich particles to γ-matrix with the increasing of aging time at 650 ？ C. The growth rate of Cu-rich phase at 650 ℃ long time aging is very slow and the average diameters of Cu-rich phase have been determined by TEM method. Cu-rich phase keeps in about 30 nm till 650 ℃ aging for 10 000 h. It shows that nano-size Cu-rich phase precipitation strengthening can be kept for long time aging at 650 ℃ because of its excellent stability at high temperatures. According to structure stability study and mechanical properties determination results the Cu-rich phase precipitation sequence and its strengthening mechanism model have been suggested and discussed.

关键词： Austenitic heat-resistant steel Precipitation strengthening Cu-rich phase MX M 23 C 6

Effect of Nitrogen Doping on the Electrical Properties of 3C-SiC Thin Films for High-Temperature Sensors Applications

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 168-174页

作者： H.K.E.Latha A.Udayakumar V.Siddeswara Prasad Department of Instrumentation Technology Siddaganga Institute of Technology materials Science Division Council of Scientific and Industrial Research-National Aerospace Laboratories

3C-SiC is a promising structural material for piezoresistive sensors used in high-temperature applications. For sensor development, the preparation of sensor materials and study of its electrical properties, such as resistivity, barrier height of grain boundaries, and temperature coefficient of resistivity, are important in addition to structural properties and these have to be optimized. In the present work, 3C-SiC thin film with in situ doping of nitrogen is prepared through low- pressure chemical vapor deposition by using methyl trichloro silane, ammonia, and hydrogen as precursors. Electrical properties of deposited 3C-SiC thin films with varying nitrogen doping concentration through four probe technique are studied. Atomic force microscopy investigations are carried out to study the grain size on and average root-mean-squared roughness 3C-SiC thin films. A decrease in the degree of crystallinity is observed in nitrogen-doped 3C-SiC thin films. The sheet resistivity of nitrogen-doped 3C-SiC thin film is found to decrease with increase in temperature in the range from 303 to 823 K. The sheet resistivity, average temperature coefficient of resistance, and barrier height of the grain boundaries of film doped with 17 at.% of nitrogen are 0.14 cm, -1.0 x 10-n/K, and 0.01 eV, respectively. Comparing all the nitrogen-doped 3C-SiC thin films, the film doped with 17 at.% of nitrogen exhibits an improved structural and electrical properties and it can be used as sensing material for high-temperature applications.

关键词： Low-pressure chemical vapor deposition (LPCVD) 3C-SiC thin film Resistivity Barrier height of grain boundaries: Temperature coefficient of resistivitv (TCR)

A combinatorial approach of developing alloy thin films using co-sputtering technique for displays

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Science China(Technological Sciences) 2009年第1期52卷 79-87页

作者： Jaydeep SARKAR Tien-Heng HUANG Lih-Ping WANG Peter H. McDONALD Chi-Fung LO Paul S. GILMAN Praxair Electronics 560 Route 303 Orangeburg materials and Chemical research laboratories Photovoltaic Technology Center Industrial Technology Research Institute (ITRI)

In this study we have used a combinatorial approach for producing binary and ternary alloy thin film libraries using a lab-scale RF co-sputtering system. Initially we used two elemental sputtering targets, i.e. aluminum (Al) target and neodymium (Nd) target, to produce a film library of varying composition and successfully identified a suitable composition range (1.95–2.38 at% Nd) in which resistance to hillock formation and resistivity of the film spots were found to be satisfactory in annealed state (350°C, 30 min). In another case, in order to form ternary alloy composition library we have used two sputtering targets, i.e. an Al-0.5 at% Nd alloy target and an elemental Ni target. Though, co-sputtered Al-0.6 at% Nd-0.9 at% Ni alloy films showed satisfactory resistance to hillock formation and low resistivity after annealing, film deposited from a ternary alloy target with the same composition failed to show satisfactory resistance to hillock formation during annealing. In case of Al-0.6 at% Nd-0.9 at% Ni alloy target, 250 nm thick film showed poor resistance to hillock formation than the 500 nm thick film. This clearly showed thickness-dependent hillock performance of Al-0.6 at% Nd-0.9 at% Ni alloy. In this study it was found that, in addition to the process variables, metallurgical microstructure of the alloy sputtering targets had significant effect on the film properties which was not obvious from the results of films deposited using co-sputtering of the individual elemental targets.

关键词： co-sputtering thin films aluminum alloys displays

Thermodynamic assessment of Mg-Ga binary system

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Transactions of Nonferrous Metals Society of China 2010年第3期20卷 450-457页

作者：孟凡桂王江戎茂华刘立斌金展鹏 School of materials Science and Engineering Central South University of Forestry and Technology School of materials Science and Engineering Central South University Swiss Federal laboratories for materials Testing and research Laboratory for Joining and Interface Technology School of Science Hunan University of Technology

In order to obtain the thermodynamic description of the Mg-Ga binary system,the thermodynamic assessment of the system was carried out using the CALPHAD method through Thermo-calc software package based on the evaluation of all available experimental data from the published *** solution phases,including liquid,hcp(Mg) and orthorhombic(Ga),were described by the substitutional solution model,of which the excess Gibbs energies were expressed with the Redlich-Kister ***,all intermetallic compounds,Mg5Ga2,Mg2Ga,MgGa,MgGa2 and Mg2Ga5,were modeled as stoichiometric compounds.A set of self-consistent thermodynamic parameters formulating the Gibbs energies of various phases in the Mg-Ga binary system were obtained *** much better agreement is achieved between the calculated results and the reported experimental data.

关键词： Mg-based alloys phase diagram thermodynamic CALPHAD method Mg-Ga binary system

Longs short-term based semi-supervised memory encoder-decoder for early prediction of failures in self-lubricating bearings

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Friction 2023年第1期11卷 109-124页

作者： Vigneashwara PANDIYAN Mehdi AKEDDAR Josef PROST Georg VORLAUFER Markus VARGA Kilian WASMER Laboratory for Advanced materials Processing(LAMP) Swiss Federal Laboratories for Materials Science and Technology(Empa)Thun CH-3602Switzerland AC2T research GmbH Wiener Neustadt 2700Austria

The existing knowledge regarding the interfacial forces,lubrication,and wear of bearings in real-world operation has significantly improved their designs over time,allowing for prolonged service *** a result,self-lubricating bearings have become a viable alternative to traditional bearing designs in industrial ***,wear mechanisms are still inevitable and occur progressively in self-lubricating bearings,as characterized by the loss of the lubrication film and ***,monitoring the stages of the wear states in these components will help to impart the necessary countermeasures to reduce the machine maintenance *** article proposes a methodology for using a long short-term memory(LSTM)-based encoder-decoder architecture on interfacial force signatures to detect abnormal regimes,aiming to provide early predictions of failure in self-lubricating sliding contacts even before they *** sliding experiments were performed using a self-lubricating bronze bushing and steel shaft journal in a custom-built transversally oscillating tribometer *** force signatures corresponding to each cycle of the reciprocating sliding motion in the normal regime were used as inputs to train the encoder-decoder architecture,so as to reconstruct any new signal of the normal regime with the minimum *** this semi-supervised training exercise,the force signatures corresponding to the abnormal regime could be differentiated from the normal regime,as their reconstruction errors would be very *** the validation procedure for the proposed LSTM-based encoder-decoder model,the model predicted the force signals corresponding to the normal and abnormal regimes with an accuracy of 97%.In addition,a visualization of the reconstruction error across the entire force signature showed noticeable patterns in the reconstruction error when temporally decoded before the actual critical failure point,making it possible to be used for early predic

关键词： predictive maintenance in-situ sensing long short-term memory(LSTM) encoder-decoder wear monitoring tribology

Structural and Optical Properties of Graphene Oxide Prepared by Modified Hummers’Method

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Computers, materials & Continua 2016年第6期52卷 175-185页

作者： N.Selvakumar Uday Pradhan S.B.Krupanidhi Harish C.Barshilia Nanomaterials research Lab Surface Engineering DivisionCSIR-National Aerospace LaboratoriesBangalore-560017India materials research Center Indian Institute of ScienceBangalore-560012India

Graphene oxide was synthesized from graphite flakes using modified Hummers’*** interlayer spacings of graphite,graphite oxide and graphene oxide were measured using X-ray diffraction *** C/O atomic ratios of graphite oxide and graphene oxide were calculated from XPS *** transformation of graphite to graphite oxide and finally to graphene oxide was clearly observed from the micro-Raman spectroscopy data and was confirmed from the FESEM ***-VIS-NIR spectrophotometer was used to study the absorbance of graphene oxide and reduced graphene oxide ***,the chemically reduced graphene oxide was heat-treated in air to obtain chemically modified graphene.

关键词： Graphene oxide Graphite,modified Hummers’method thermal annealing optical properties

Friction stir butt welding of A5052-O aluminum alloy plates

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中国有色金属学会会刊：英文版 2012年第S3期22卷 619-623页

作者： Sung-Ook YOON Myoung-Soo KANG Hyun-Bin NAM Yong-Jai KWON Sung-Tae HONG Jin-Chun KIM Kwang-Hak LEE Chang-Yong LIM Jong-Dock SEO School of materials Science and Engineering University of Ulsan School of Mechanical Engineering University of Ulsan Technical research laboratories Shin Young Co.Ltd.

Friction stir butt welding (FSW) between A5052-O aluminum alloy plates with a thickness of 2 mm was *** rotation speeds of the welding tool were 2000 and 3000 r/min,*** traverse speed was ranged from 100 mm/min to 900 mm/*** defect-free welds with the very smooth surface morphology were successfully obtained,except for at the welding condition of 3000 r/min and 100 mm/*** onion ring structure was observed in the friction-stir-welded zone (SZ) at the condition of 2000 r/min and 100 mm/*** all the welding conditions,the grain size of the SZ was smaller than that of the base metal,and was decreased with the decrease of the tool rotation speed and with the increase of the tool traverse *** stir zone exhibited higher average hardness than the base *** decrease of the tool rotation speed and the increase of the tool traverse speed resulted in the increase in the average hardness of the *** tensile strength of the FSWed plates was similar to that of the base metal,except for at the welding condition of 3000 r/min and 100 mm/*** total elongation of the FSWed plates was lower than that of the base metal.

关键词： friction stir butter welding A5052-O aluminum alloy microstructure mechanical property

Effect of Boron Concentration on Dynamic Recrystallization Behavior of Low-Carbon Steel

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 931-939页

作者： Yong-Liang Gao Xiang-Xin Xue He Yang Liaoning Key laboratories of Ecological Utilization Technology of Boron Resources and Boron materials Northeastern University

The dynamic recrystallization behavior of low-carbon steel containing three different amounts of boron（0.002,0.004,and 0.006 wt%） was systematically investigated under various experimental ***-carbon steel was exposed to temperatures ranging from 900 to 1100 ℃,strain rates from 0.1 to 10 s^-1,and inspection of the initial austenite grain size at 1150℃.The resulting stress–strain curves are observed to possess two classifications of behavior,dynamic recovery and dynamic recrystallization,while the initial austenite grain size increases directly proportional to boron ***,the characteristic points of the flow curves were analyzed by regression method in which the peak and critical stresses decreased in response to an increase in boron composition,indicating that a softening effect appears with the addition of *** the contrary,peak and critical strains increased as boron content increased,indicating that boron has the ability to delay the onset of dynamic ***,the kinetics model of dynamic recrystallization for three boron-treated steels was established.

关键词： Boron-treated steel Hot deformation Flow stress Dynamic recrystallization