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dEVELOPMENT ANd CHArACTErIZATION OF NEW BIOMEdICAL ALLOYS BASEd ON NiCrMo ANd NiCrMoTa

UPB Scientific Bulletin, Series B: Chemistry and Materials science 2024年第4期2024卷 281-290页

作者： Baciu, Florentina Iacob, Gheorghe Niculescu, Florentina Buţu, Mihai Geambazu, Laura Manea, Ciprian-Alexandru Manta, Eugen drăguţ, dumitru-Valentin Ghiţă, Andreea-Nicoleta Matei, Alexandru-Cristian Şolea, roxana-Marina Faculty of Materials Science and Engineering National University of Science and Technology POLITEHNICA Bucharest Romania National Institute for R&D in Electrical Engineering ICPE-CA Bucharest Romania National R&D Institute for Non-Ferrous and Rare Metals—IMNR Bucharest Romania

In the present work, we proposed the development of a new type of biomedical alloy-NiCrMoTa with improved structural properties compared to the basic NiCrMo alloy. The studied alloys were obtained by melting in a vacuum melting furnace in a neutral atmosphere and were characterized chemically and microstructurally through X-ray fluorescence spectrometry (XrFS), optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EdS). These techniques highlighted the microstructures and elemental compositions of the NiCrMo and NiCrMoTa alloys. © 2024, Politechnica University of Bucharest. All rights reserved.

关键词： Energy dispersive spectroscopy

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Mn-doped SrCoO_(3-δ) Perovskite Oxides for Ethylene Production via Chemical Looping Oxidative dehydrogenation of Ethane

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China Petroleum Processing & Petrochemical Technology 2024年第3期26卷 53-62页

作者： Li Zhi Liu Linjiao Hao daijun ren Xiaohang Shen Fangxia Li Xin Yu Anping Luoyang R&D Center of Technology of Sinopec Engineering(Group)Co.Ltd. Luoyang 471003China

Chemical looping oxidative dehydrogenation (CL-OdH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers. Inthis study, perovskite-type oxide SrCoO_(3-δ) and B-site Mn ion-doped oxygen carriers (SrCo_(1-x)MnxO_(3-δ), x=0.1, 0.2, 0.3)were prepared and tested for the CL-OdH of ethane. The oxygen-deficient perovskite SrCoO_(3-δ) exhibited high ethyleneselectivity of up to 96.7% due to its unique oxygen vacancies and lattice oxygen migration rates. However, its low ethyleneyield limits its application in the CL-OdH of ethane. Mn doping promoted the reducibility of SrCoO_(3-δ) oxygen carriers,thereby improving ethane conversion and ethylene yield, as demonstrated by characterization and evaluation experiments.X-ray diffraction results confirmed the doping of Mn into the lattice of SrCoO_(3-δ), while X-ray photoelectron spectroscopy(XPS) indicated an increase in lattice oxygen ratio upon incorporation of Mn into the SrCoO_(3-δ) lattice. Additionally, H2temperature-programmed reduction (H2-TPr) tests revealed more peaks at lower temperature reduction zones and a declinein peak positions at higher temperatures. Among the four tested oxygen carriers, SrCo0.8Mn0.2O_(3-δ) exhibited satisfactoryperformance with an ethylene yield of 50% at 710 °C and good stability over 20 redox cycles. The synergistic effect of Mnplays a key role in increasing ethylene yields of SrCoO_(3-δ) oxygen carriers. Accordingly, SrCo0.8Mn0.2O_(3-δ) shows promisingpotential for the efficient production of ethylene from ethane via CL-OdH.

关键词： ethane ethylene perovskite chemical looping oxidative dehydrogenation

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Pitting corrosion initiated by SiO_(2)-MnO-Cr_(2)O_(3)-Al_(2)O_(3)-based inclusions in a 304 stainless steel

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Journal of Iron and Steel research International 2024年第9期31卷 2281-2293页

作者： Jin-zhen Hu Shi Li Ji Zhang Ying ren Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina Stainless Steel R&D Center of Central R&D Institute Baoshan Iron and Steel Co.Ltd.Shanghai201900China School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

The influence of the aluminum content on the pitting corrosion of a 304 stainless steel by a Cl−solution was *** number,area,and composition of non-metallic inclusions were modified by the addition of aluminum in the steel,which was responsible for the variation of the corrosion degree of the 304 stainless *** detection,corrosion test,electrochemical test,thermodynamic calculation,and first-principles calculation were performed to evaluate the pitting corrosion of the stainless *** initiation of the pitting corrosion by three types of inclusions,including(Mn,Si,Cr,S)O,(Mn,Al,Cr)O,and Al_(2)O_(3)were in-situ *** corroding for 880 min,the corrosion index of(Mn,Si,Cr,S)O,(Mn,Al,Cr)O,and Al_(2)O_(3)was 0.38%,0.02%,and 0.00%min−1,*** the increase in aluminum content in the steel,the pitting potential of the stainless steel was 0.131,0.304,and 0.338 V,respectively,indicating that a higher aluminum content in the steel was beneficial to improving the pitting corrosion resistance of the 304 stainless steel.

关键词： Pitting corrosion 304 stainless steel Non-metallic inclusion First-principles calculation Galvanic corrosion

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Prediction of dissolved gas content in transformer oil based on multi-information fusion

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High Voltage 2024年第3期9卷 685-699页

作者： Tongliang Yang Yun Fang Chengming Zhang Chao Tang dong Hu College of Engineering and Technology Southwest UniversityChongqingChina International R&D Center for New Technologies of Smart Grid and Equipment Southwest UniversityChongqingChina

In order to accurately predict the content and variation trend of dissolved gas in trans-former oil and guide the condition maintenance of power transformers,a combined prediction model based on multi-information fusion is proposed and its effectiveness is *** of all,based on the possibility of pathological and missing historical sample data,a detection and filling method based on variable weight combination samples is ***,the authors propose two *** at the non-linear and non-stationary characteristics of gas content,a univariate decomposition prediction mode HBA-VMd-TCN which based on the Honey Badger algorithm,variational mode decomposition and time convolutional network(TCN)is *** the multi-variate Informer prediction model is established for gas content affected by multiple ***,the cross-entropy theory is used to determine the weight coefficients of the two models,and the multi-information fusion combined prediction model is ***,on the basis of the above,a method to determine the time step and the position information of the transition point adaptively in the process of prediction is proposed to further improve the prediction *** results show that,through a series of simulation experiments of model comparison and transformer anomaly prediction,the accuracy and effectiveness of the combined prediction model are verified.

关键词： content prediction dissolved

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research on welding deformation control technology of battery electric vehicle framed aluminum body

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Progress in Natural science:Materials International 2024年第1期34卷 108-121页

作者： Bo Liu Jian Yang Jia Li Xiaolin Liao Qin Yang Jinsheng Zhang Tiegang Hu Shuxun Jiang School of Mechanical Engineering University of Science and Technology Beijing Chongqing Industry Polytechnic College Global R&D Center Chongqing Changan Automobile Co. Ltd Farizon New Energy Commercial Vehicle Group

The welding process of aluminum(Al) alloy car body has problems such as poor weld quality, low welding co-efficient, and large welding deformation. This paper mainly focuses on material accuracy design, lap structure design, simulation, and process manufacturing to break through the precision control problems caused by welding deformation of battery electric vehicle Al alloy car body. First, the 209 key functional dimensional chains of Al body-in-white are analyzed and decomposed to component and profile tolerance dimensions step by ***, the differences of vertical butt, bevel butt, and plug structures are studied and joint matching is implemented in a targeted manner. Subsequently, through welding deformation simulation analysis and welding sequence optimization, the body-in-white welding process and tooling fixtures are guided and designed to ensure that the dimensional accuracy of the Al body is controlled to ±2 mm in all aspects. Finally, the design of the whole vehicle arrangement of mechanical, human-machine, and major components is carried out, and an all-Al framed battery electric vehicle lightweight platform with different sizes and ranges is innovatively created. The difficulties such as the contradiction between power battery size and arrangement space, unreasonable arrangement position, and load distribution are solved.

关键词： Aluminum alloy Frame structure Welding deformation simulation dimensional accuracy control Battery electric vehicle lightweight platform

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development paradigms of cyberspace endogenous safety and security

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science China(Information sciences) 2022年第5期65卷 264-266页

作者： Jiangxing WU National Digital Switching System Engineering & Technological R&D Center

Scientifc interpretation of paradigm. The concept and theory of paradigm were first proposed by Thomas Kuhn, a famous American science philosopher, and were systematically described in his book “The Structure of Scie... 详细信息

关键词： cyberspace endogenous security ubiquitous problem unknown unknown security threats relatively-correct axiom dynamic heterogeneous redundancy architecture cyberspace endogenous safety and security development paradigm

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Biaxial stretching of polytetrafluoroethylene in industrial scale to fabricate medical ePTFE membrane with node-fibril microstructure

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regenerative Biomaterials 2023年第1期10卷 1161-1177页

作者： Gang Wang Yusheng Feng Caiyun Gao Xu Zhang Qunsong Wang Jie Zhang Hongjie Zhang YongqiangWu Xin Li Lin Wang Ye Fu Xiaoye Yu deyuan Zhang Jianxiong Liu Jiandong ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China R&D Center Lifetech Scientific(Shenzhen)Co.Ltd.Shenzhen 518057China R&D Center Lifevalve Medical Scientific Co.Ltd.Shenzhen 518057China

Expanded polytetrafluoroethylene(ePTFE)is promising in biomedical fields such as covered stents and plastic surgery owing to its excellent biocompatibility and mechanical ***,ePTFE material prepared by the traditional biaxial stretching process is with thicker middle and thinner sides due to the bowing effect,which poses a major problem in industrial-scale *** solve this problem,we design an olive-shaped winding roller to provide the middle part of the ePTFE tape with a greater longitudinal stretching amplitude than the two sides,so as to make up for the excessive longitudinal retraction tendency of the middle part when it is transversely *** as-fabricated ePTFE membrane has,as designed,uniform thickness and node-fibril *** addition,we examine the effects of mass ratio of lubricant to PTFE powder,biaxial stretching ratio and sintering temperature on the performance of the resultant ePTFE ***,the relation between the internal microstructure of the ePTFE membrane and its mechanical properties is *** stable mechanical properties,the sintered ePTFE membrane exhibits satisfactory biological *** make a series of biological assessments including in vitro hemolysis,coagulation,bacterial reverse mutation and in vivo thrombosis,intracutaneous reactivity test,pyrogen test and subchronic systemic toxicity test;all of the results meet the relevant international *** muscle implantation of the sintered ePTFE membrane into rabbits indicates acceptable inflammatory reactions of our sintered ePTFE membrane fabricated on industrial *** a medical-grade raw material with the unique physical form and condensed-state microstructure is expected to afford an inert biomaterial potentially for stent-graft membrane.

关键词： biomedical polymer medical-grade raw material expanded polytetrafluoroethylene olive roller polymer processing biaxial stretching

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A Biosurfactant-containing TSd Strategy to Modify Bovine Pericardial Bioprosthetic Valves for Anticalcification

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Chinese Journal of Polymer science 2023年第1期41卷 51-66页

作者： Cai-Yun Gao Gang Wang Lin Wang Qun-Song Wang Han-Cheng Wang Lin Yu Jian-Xiong Liu Jian-dong ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China R&D Center Lifetech Scientific(Shenzhen)Co.Ltd.Shenzhen518057China R&D Center Lifevalve Medical Scientific Co.Ltd.Shenzhen518057China

Bioprosthetic heart valves(BHVs)are important for transcatheter valve *** commercial BHVs on the market are basically porcine or bovine pericardium(BP)crosslinked with glutaraldehyde(GA).Simply applying GA to BHVs can enhance mechanical stability,but cannot alleviate in vivo *** this work,we developed a two-step decellularization(TSd)strategy to modify this biomacromolecular network,in which BP was post-treated,as the second step of decellularization,with a mild biosurfactant n-dodecyl-β-d-maltoside in a mixture of isopropanol and phosphate-buffered saline after the first step of traditional decellularization and GA *** TSd-treated BP exhibited not only low cytotoxicity and excellent mechanical properties in vitro,but also low immune responses and significant anticalcification in *** 60 days of subcutaneous implantation in the back of Wistar rats,the calcium content was,as quantified with an inductively coupled plasma optical emission spectrometer,only 1.1µg/mg compared to 138.6µg/mg in the control group without the *** addition,collagen fibrils were observed with field emitting scanning electron microscopy(SEM),and the morphology and composition of the calcified sites resulting from in vivo biomineralization were studied with SEM with energy dispersive spectroscopy and also X-ray *** study proposes a facile yet effective anticalcification strategy for the modification of the bovine pericardial bioprosthetic heart valve,a natural biomacromolecular network.

关键词： Heart valve Anticalcification Collagen In vivo biomineralization Transcatheter aortic valve implantation(TAVI) Extracellular matrix Biomacromolecular network Biosurfactant Bovine pericardium

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THE INFLUENCE OF SPArK PLASMA SINTErING PArAMETErS ON THE PHYSICAL PrOPErTIES OF CoCrMoNbTi Bio-HEA

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UPB Scientific Bulletin, Series B: Chemistry and Materials science 2024年第3期86卷 227-236页

作者： Bololoi, Alina Elena Manea, Ciprian Alexandru Antoniac, Iulian Vasile Bololoi, robert Viorel Cojocaru, Vasile dănuţ Tălpeanu, dorinel Pătroi, delia Geambazu, Laura Elena Material Science and Engineering Faculty National University of Science and Technology POLITEHNICA Bucharest Romania National Institute for R&D in Electrical Engineering ICPE-CA Bucharest Romania

The paper presents the influence of the sintering temperature parameter on the physical properties of CoCrMoNbTi high entropy alloy intended for biomedical applications. CoCrMoNbTi HEA metallic powder preparation method was disseminated previously. The alloy was consolidated by spark plasma sintering in order to produce bulk materials which could be further processed. The produced samples were analyzed monitoring the structure, apparent density and hardness modifications. The microstructural and chemical analyses results indicated a good elemental distribution and compaction, with no contamination present. Hardness and density measurements indicated a direct proportional increase with the temperature. © 2024, Politechnica University of Bucharest. All rights reserved.

关键词： Brinell Hardness

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development and application of magnesium alloy parts for automotive OEMs:A review

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Journal of Magnesium and Alloys 2023年第1期11卷 15-47页

作者： Bo Liu Jian Yang Xiaoyu Zhang Qin Yang Jinsheng Zhang Xiaoqing Li School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Global R&D Center Chongqing Changan Automobile Co.LtdChongqing 401120China

China is currently vigorously implementing the“energy conservation and emission reduction”and“dual carbon”*** the most resource-advantaged light metal material in China,Magnesium(Mg)alloy is progressively expanding its application in automobile,rail transportation,aerospace,medical,and electronic *** University,Shanghai Jiaotong University,and Australian National University have conducted extensive research on the preparation,properties,and processes of Mg *** the past 20 years,the proportion of Mg alloy in the automotive industry has gradually expanded,whereas currently the design and development of Mg alloy parts for automobiles has rarely been ***,the application models and typical parts cases of Mg alloy are summarized mainly from the four systems of the whole vehicle(body system,chassis system,powertrain system,interior,and exterior system).Subsequently,two actual original equipment manufacturers(OEM)cases are used to introduce the development logic of reliable die-cast Mg alloy,including forward design,formability analysis,process design analysis,structural redesign,manufacturing,and testing,aiming to share the methods,processes,and focus of attention of automotive OEMs for developing Mg alloy parts to enhance the confidence and motivation of applying Mg alloy in automotive ***,the multiple challenges faced by Mg alloy materials are sorted out and how to face these challenges are *** policies and regulations,environmental protection and energy saving,and consumer demand will continue to promote the application of Mg.

关键词： Magnesium alloy Original equipment manufacturer Automotive application development process

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