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DIMENSIONAL INSTABILITy OF LD31 Al ALLOy WELDMENTS AT ROOM TEMPERATURE AND AFTER ThERMAL CyCLES

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 64-70页

作者： X.S.Liu h.y.fang W.L.Xu X.T.Tian X.D.Sun National key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaNational key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaNational key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaNational key Laboratory of Advanced Welding Production and Technology Harbin Institute of Technology Harbin 150001ChinaHarbin First Mechanical Production Factory Harbin 150080China

The unstable dimensional distortion of LD31 aluminum alloy weldments at room temperature and after thermal cycles was studied by use of light interference and CMM(three-coordinate measuring machines). At the same time, distortion mechanism was analyzed from the viewpoint of mechanics and micro structure. Experimental results show that there exists obvious difference of unstable dimensional distortion between LD31 welded specimens under two conditions mentioned above. Under room temperature, dimensional variation of welded specimens will decrease gradually and finally tends to be stable during 200h after welding. The relative elongation of welded specimen is 3.0×10-5; After thermal cycles, distortion of welded specimen is much larger than that at room temperature. After 11 thermal cycles, the dimension will tend to be stable. Dimensional unstable distortion of weldments mainly results from temperature condition, microstructure variation and relaxation of welding residual stress.

关键词： LD31 aluminum alloy light interference room temperature and thermal cycles dimensional instability

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硫磺处理的竹子用于低交通量道路

国外公路 1980年第5期 41-44页

作者： h.y.fang 辛济平

本文介绍硫磺处理的竹子用于道路建筑方面的最近研究成果。对竹茎的基本工程特性,包括弹性模量、抗压和抗拉强度,以及竹子和水的相互作用方面,作了讨论和摘录。对工程用的竹子结构的特性和耐用性进行了试验。最后提出竹子加筋土用于低... 详细信息

本文介绍硫磺处理的竹子用于道路建筑方面的最近研究成果。对竹茎的基本工程特性,包括弹性模量、抗压和抗拉强度,以及竹子和水的相互作用方面,作了讨论和摘录。对工程用的竹子结构的特性和耐用性进行了试验。最后提出竹子加筋土用于低交通道路以防坍方的实地应用方法。建筑道路,一般需要大批的材料。鉴于经济考虑是主要的决定因素之一,有必要对可用于道路建筑的代替材料或廉价材料进行试验。在某些地区,普通的建筑材料例如

关键词：竹子耐用性加筋土工程特性低交通量道路竹筋混凝土硫磺无机杀菌剂

Stress Analysis of the Aperture in Compound Pipeline by FEM

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Stress Analysis of the Aperture in Compound Pipeline by FEM

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

The Fourth International Conference on Physical and Numerical Simulation of Materials (ICPNS’2004)

作者： J.G.yANG h.y.fang C.L.FAN M.LI Z.LUO X.Z.hOU State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001. China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001. China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001. China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001. China School of Material Science and Technology Tianjin University Tianjin 300072 China DAQING Oil-chem-welding Institute Daqing 163712 China

＜正＞There is a cyclical aperture at the certain part of fiberglass reinforced plastic compound pipeline with stainless steel pipe as liner, where it becomes the weakness of the conduit. In this paper the field of stress and strain of the aperture was investigated by using the non-liner finite element code MARC. The results of finite element analysis show there are concentrations of stress and strain in the layer of stainless steel at the part of the pipeline where the aperture exists. The method to solve these problems was also discussed in this paper.

关键词： Compound pipeline Stress MARC

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.y.huang Z.yang S.y.yang Z.h.Dai y.J.Liu J.h.Liao G.y.Zhong Z.J.Xie y.P.fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure heterostructure Photothermal effect Photocatalyst hydrogen evolution

Viral and nonviral nanocarriers for in vivo CRISPR-based gene editing

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Nano Research 2024年第10期17卷 8904-8925页

作者： Zhongyuan Guo Audrey T.Zhu Ronnie h.fang Liangfang Zhang Aiiso yufeng Li Family Department of Chemical and Nano Engineering University of California San DiegoLa JollaCA 92093USA Division of host-Microbe Systems and Therapeutics Department of PediatricsUniversity of California San DiegoLa JollaCA 92093USA

The continued development of clustered regularly interspaced short palindromic repeats(CRISPR)technology has the potential to greatly impact clinical medicine,particularly for disease diagnosis and *** high demand for the in vivo delivery of CRISPR-based therapies,significant challenges *** include rapid degradation by enzymes,inefficient disease site targeting,and the risk of undesired off-target *** platforms,with their tailorable properties,have been engineered to efficiently package CRISPR payloads in various formats,including as plasmid DNA,mRNA,and ribonucleoprotein complexes,for in vivo *** them,recombinant adeno-associated viruses,virus-like particles,and lipid nanoparticles have displayed exceptional *** review will discuss the development of these and other nanocarriers for in vivo CRISPR-based genome editing.

关键词： clustered regularly interspaced short palindromic repeats(CRISPR) in vivo gene editing nanocarriers recombinant adeno-associated viruses(rAAVs) virus-like particle(VLP) lipid nanoparticle(LNP)

A methodology for laser tool setters calibration and its precise mathematical model

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Chinese Journal of Aeronautics 2024年第7期37卷 564-581页

作者： Tao fang Zixi fang Ze Zhong ChEN Zhiyong ChANG School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China Gina Cody School of Engineering and Computer Science Concordia UniversityMontrealQuebec H3G 1M8Canada Changsha Optimum CNC Corporation Changsha 410221China Institute for Aero-engine Smart Assembly of Shaanxi Province Xi’an 710072China

On-machine tool setting is a pivotal approach in achieving intelligent manufacturing,and laser tool setters have become a crucial component of smart machine *** tool setters play a crucial role in precisely measuring the dimensions of cutting tools during the part machining process,focusing on tool length and *** a measuring instrument,the positions of the laser axis of the laser tool setter need to be accurately calibrated before ***,in actual calibration scenarios,traditional calibration methods face challenges due to installation errors in the tool setter and geometric errors in the measuring *** address this issue,this study proposes a novel calibration ***,the calibration mechanism of the laser beam axis is *** on the accurate mathematical model of the laser beam and the measuring rod,and using the polygon clipping algorithm,the mathematical mechanism of the laser tool setter’s work is ***,a novel method is introduced to calculate the compensation distance between the laser beam reference point and the rod bottom center point at each moment during ***,by utilizing the kinematic chain of the tool setter calibration system,a new calibration method is developed to accurately calibrate the position of the laser beam axis in the machine tool coordinate ***,the accuracy of the calibration method is verified through simulation experiments and calibration *** method improves the calibration accuracy of the tool setter,and the mathematical model of the laser tool setter can be extended to the measurement of tools,thereby improving the precision of tool *** research significantly improves the efficient production performance of smart machine tools.

关键词： On-machine tool setting Smart machine tools Mathematical model Calibration method Laser tool sette

On hamiltonian Property of Cayley Digraphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： fang DUAN Qiong-xiang hUANG School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and C(G,S) the Cayley digraphs of G with connection set *** this paper,we give some sufficient conditions for the existence of hamiltonian circuit in C(G,S),where G=Zm×h is a semiproduct of Zmby a subgroup h of *** particular,if m is a prime,then the Cayley digraph of G has a hamiltonian circuit unless G=Zm×*** addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that C(Zm,{a})×_φ C(h,S) is also a Cayley digraph if φ is a homomorphism from h to{1,-1} ≤ Zm~*,which produces some classes of Cayley digraphs that have hamiltonian circuits.

关键词： Cayley digraphs hamiltonian circuit external semidirect product

Pancreatic panniculitis as the first presentation of pancreatic ductaladenocarcinoma

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hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 106-108页

作者： Wei-fang Zhu Shan fang Jian-Jun Qiao Department of Dermatology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

To the Editor:Pancreatic panniculitis,also known as pancreatic fat necrosis or enzymatic panniculitis,is a rare type of panniculitis that occurs in 0.3%−3%of patients with pancreatic disease such as acute or chronic pancreatitis and pancreatic carcinoma,especially acinar cell carcinoma[1,2].The clinical manifestations are nonspecific erythema tender nodules.

关键词： Pancreatic acute adenocarcinoma

Fe-N-C core-shell catalysts with single low-spin Fe(Ⅱ)-N_(4)species for oxygen reduction reaction and high-performance proton exchange membrane fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 538-546,I0013页

作者： yan Wan Linhui yu Bingxin yang Caihong Li Chen fang Wei Guo fang-Xing Xiao yangming Lin Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021FujianChina Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002FujianChina College of Materials Science and Engineering Fuzhou UniversityNew CampusMinhou 350108FujianChina College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117FujianChina

Fe-N-doped carbon materials(Fe-N-C)are promising candidates for oxygen reduction reaction(ORR)relative to Pt-based catalysts in proton exchange membrane fuel cells(PEMFCs).however,the intrinsic contributions of Fe-N_(4)moiety with different chemical/spin states(e.g.D1,D2,D3)to ORR are unclear since various states coexist *** the present work,Fe-N-C core-shell nanocatalyst with single lowspin Fe(Ⅱ)-N_(4)species(D1)is synthesized and identified with ex-situ ultralow temperature Mossbauer spectroscopy(T=1.6 K)that could essentially differentiate various Fe-N_(4)states and invisible Fe-O *** quantifying with CO-pulse chemisorption,site density and turnover frequency of Fe-N-C catalysts reach 2.4×10^(-9)site g^(-1)and 23 e site~(-1)s^(-1)during the ORR,***-wave potential(0.915V_(RhE))of the Fe-N-C catalyst is more positive(approximately 54 mV)than that of Pt/***,we observe that the performance of PEMFCs on Fe-N-C almost achieves the 2025 target of the US Department of Energy by demonstrating a current density of 1.037 A cm^(-2)combined with the peak power density of 0,685 W cm^(-2),suggesting the critical role of Fe(Ⅱ)-N_(4)site(D1).After 500 h of running,PEMFCs still deliver a power density of 1.26 W cm^(-2)at 1.0 bar h_(2)-O_(2),An unexpected rate-determining step is figured out by isotopic labelling experiment and theoretical *** work not only offers valuable insights regarding the intrinsic contribution of Fe-N_(4)with a single spin state to alkaline/acidic ORR,but also provides great opportunities for developing high-performance stable PEMFCs.

关键词： Fuel cells Oxygen reduction reaction Non-platinum group metals(PGMs) Isotopic labelling Active site TOF