检索结果-南通市图书馆

Effects of Shot Peening Process on Thermal Cycling Lifetime of TBCs Prepared by EB-PVD

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2007年第2期20卷 145-147页

作者： ZHOU Zhao-hui GONG Sheng-kai LI He-fei xu hui-bin ZHANG Chun-gang WANG Lu School of Materials Science and Engineering Beij＇ing University of Aeronautics and Astronautics Beij＇ing 100083 China Shenyang Liming.4ero-Engine Group Corporation Shenyang 110043 China

Conventional two-layered thermal barrier coatings （TBCs） are prepared by electron beam physical vapor deposition （EB-PVD） with ZrO2-8 wt% Y2O3 （8YSZ） as top coat and CoCrAlY as bond coat on disk-shaped Ni based super-alloy. In this paper, three kinds of shot peening process with different lengths of operating time were adopted for bond coating. As a result, changes took place in its surface roughness and the surface micro-hardness. A thermal cycling test at 1 273 Kx55 rain and another at room temperature for 5 min were performed to study the effects of shot peening process on the thermal cycling lifetime of TBCs. It is found that a moderate shot peening process will be able to prolong the life time. The oxidation dynamic of the as-processed TBCs basically accords with the parabolic rule, and the oxidation test also attests to the spallation between YSZ and thermal growth oxide （TGO） responsible mainly for the failure of TBCs.

关键词： thermal cycling lifetime shot peening thermal barrier coatings (TBCs)

Oxidation and thermal fatigue of EB-PVD thermal barrier coatings on tube superalloy substrate

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2006年第A02期16卷 10-13页

作者： GAO Yu ZHANG Chun-xia ZHOU Chun-gen GONG Sheng-kai xu hui-bin Department of Materials Science and Engineering B eijing University of Aeronautics and Astronautics Beijing 100083 China

Two-layer structured thermal barrier coatings (TBCs) (NiCoCrAlY (bond coat)+(6%-8%, mass fraction) Y2O3-stabilized ZrO2(YSZ top coat)) were deposited by electron beam physical vapor deposition (EB-PVD) on tube superalloy substrates. The samples were investigated by isothermal oxidation and thermal shock tests. It is found that the mass gains of the,substrate with and 2 without TBCs are 0.165 and 7.34 mg/cm(2), respectively. So the TBCs system is a suitable protection for the substrate. In thermal shock tests the vertical cracks initiate at the top coat and grow into the bond coat, causing the oxidation of the bond coat along the cracks. Failure of the TBCs system occurs by the spallation of the YSZ from the bond coat, and some micro-cracks are found at the location where the fragment of the YSZ top coat spalled from.

关键词：超耐热合金管状基质 EB-PVD 电子束物理汽相淀积氧化热冲击热障涂层热疲劳

Preparation and Properties of the Ni2MnGa Magnetic Shape Memory Alloy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第4期17卷 296-297页

作者： LIANG Ting xu hui-bin JIANG Cheng-Bao GONG Sheng-kai Department of Materials Science and Engineeringj Beijing University of Aeronautics and Astronautics Beijing 100083 Department of Mechanics Command and Engineering College of Chemical DefenceBeijing 102205

The polycrystalline Ni_(48.2)Mn_(22.4) Ga_(29.4) alloys were prepared by means of melting in argon arc furnace.X-ray diffraction pattern indicates a fcc cubic structure with a lattice parameter of 0.5822nm at room *** phase transformation temperatures were:1℃for martensite start temperature,-11℃for martensite finish temperature,3℃for austenite start temperature and 11℃for austenite start temperature,*** results showed that the effect of magnetic field on the strains increases with the decrease of temperature.A strain of 2.1×10^(-4)was obtained with an applied magnetic field of 5 kOe at-66℃.

关键词： Ni2MnGa temperature. martensite

Enhancing reversible hydrogen storage performance of 2LiBH_(4)–MgH_(2)via in-situ building heterogeneous nucleation sites

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第9期43卷 4367-4376页

作者： Wei Chen Ya-hui Sun Tian xu xue-bin Yu Guang-Lin Xia Department of Materials Science Fudan UniversityShanghai 200433China

2LiBH_(4)-MgH_(2)composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB_(2)during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles(AT NPs)are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of 2LiBH_(4)-MgH_(2)*** the initial H_(2)desorption process,MgAlB_(4)and TiB_(2)that have identical crystal structure and low d-value mismatch with MgB_(2)resulting from the reaction between AT NPs and 2LiBH_(4)-MgH_(2)composite serve as effective nucleation sites for the formation of MgB_(2).As a result,the apparent activation energy of the two-step H_(2)desorption of AT NPs doped 2LiBH_(4)-MgH_(2)composite are notably decreased to(110.0±5.9)and(119.6±1.4)kJ·mol^(-1),which is 55.5 and 33.5 kJ·mol^(-1)lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H_(2)desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Reversible hydrogen storage Reactive hydride composites Catalytic effects Heterogeneous nucleation

High-temperature oxidation resistance of Si-coated C/SiC composites

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第9期43卷 4566-4572页

作者： Jie Xiao Hua-Yue Zhang Sheng-Kai Gong hui-bin xu Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structure Materials and Protective Coatings(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China

In this paper,Si coatings were sprayed onto C/SiC composite substrates by atmospheric plasma spraying(APS).The high-temperature oxidation behavior of the substrate and coating at temperatures of 1100 and 1300℃was also *** C/SiC ceramic matrix composite will be damaged seriously and even failed due to the oxidation of carbon fibers in *** Si coating effectively improved the oxidation resistance of the C/SiC substrate in the high-temperature oxidation *** effect of the thickness of the Si coatings on the oxidation resistance was *** 150-μm coating is proved to enable the substrate to have the lowest oxidation weight loss and the best oxidation resistance after static oxidation for 5 h.

关键词： Ceramic matrix composites(CMCs) Carbon fiber Si coating Oxidation Plasma spray

“互联网+”背景下福州市区中医机构中药代煎服务现状与优化路径研究

在线全文

学校读者我要写书评

暂无评论

中国处方药 2024年第1期22卷 154-157页

作者：许慧彬邓鑫邓晗旸翁曼华庞雅煦许克祥福建中医药大学人文与管理学院福州350122

中药材的煎制过程对于中药的疗效起着重要的作用。近年来,医院选择代煎中药服务的患者数量不断增多,为给患者提供便捷、有效、安全的中药汤剂,本研究站在“互联网+”新时代的历史坐标下,对福州市区六家提供中药代煎服务的中医机构进行... 详细信息

中药材的煎制过程对于中药的疗效起着重要的作用。近年来,医院选择代煎中药服务的患者数量不断增多,为给患者提供便捷、有效、安全的中药汤剂,本研究站在“互联网+”新时代的历史坐标下,对福州市区六家提供中药代煎服务的中医机构进行了实地调研走访,结合专家访谈,从人员资质、煎药设备管理、煎药流程、配送模式、信息化程度等多个角度着手,对“互联网+”背景下福州市区中医机构中药代煎的现状进行分析,并提出优化中药代煎服务的路径,以期能提升中药代煎服务质量及患者对中医药的信任度。

关键词： “互联网+” 中药代煎优化路径

Periodic Variation Studies of the Two Short Period W UMa-type Eclipsing binaries: LX Lyn and V0853 Aur

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第1期24卷 273-284页

作者： xu Zhang bin Zhang School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China

In this paper,new light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the Wilson-Devinney(W-D) *** order to explain their asymmetric LCs,cool starspots on the components were *** is suggested that their fill-out degrees are f=12.0%(LX Lyn) and f=26.3%(V0853 Aur).At the same time,we found that LX Lyn is a W-type eclipsing binary(EB) with an orbital inclination of i=84°.88 and a mass ratio of q=2.31.V0853 Aur is also a W-type CEB with a mass ratio of q=2.77 and an orbital inclination of i= 79°.*** on all available times of light minimum,their orbital period changes are studied by using the O-C *** O-C diagram of LX Lyn reveals a cyclic oscillation with a period of about 14.84 yr and an amplitude of 0.0019 days,which can be explained by the light-travel time effect(LTTE) due to the presence of a third body with a minimum mass of0.06M_⊙.For V0853 Aur,it is discovered that the O-C diagram of the system also shows a cyclic oscillation with a period of 9.64 yr and an amplitude of 0.03365 *** cyclic oscillation of V0853 Aur can be attributed to the LTTE by means of a third body with a mass no less than 3.77M_⊙.The third body may play an important role in the formation and evolution of these systems.

关键词： stars:activity (stars:)binaries(including multiple):close (stars:)binaries:eclipsing (stars:)brown dwarfs stars:evolution stars:formation

Corrosion behavior of pure metals(Ni and Ti)and alloys(316H SS and GH3535)in liquid GaInSn

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第3期35卷 70-83页

作者： Jian-hui Yu Hong-Xia xu Xiang-Xi Ye bin Leng Han-xun Qiu Xing-Tai Zhou School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were *** aim was to evaluate the corrosion performance and select a suitable candidate material for use as a molten salt manometer diaphragm in thermal energy storage *** results indicated that the alloys(316H SS and GH3535)exhibited less corrosion than pure metals(Ni and Ti)in liquid ***-rich binary intermetallic compounds were found to form on the surfaces of all the tested metal materials exposed to liquid GaInSn,as a result of the decomposition of liquid GaInSn and its reaction with the constituent elements of the metal *** corrosion mechanism for all the tested materials exposed to liquid GaInSn was also investigated and proposed,which may aid in selecting the optimal candidate material when liquid GaInSn is used as the pressure-sensing medium.

关键词： Metal materials Liquid GaInSn Corrosion Intermetallic compounds Thermal energy storage systems

Synthesis and Properties of Ferrocene Conjugated Macrocycles with Illusory Topology of the Penrose Stairs

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第5期40卷 881-886页

作者： xu Jindong LAN bin ZHU Lingyun xu hui CHEN Xinyu LI Wenjuan YUAN Yaofeng YAN Jianfeng LI Yuanming Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108P.R.China Henan Key Laboratory of Biomolecular Recognition and Sensing College of Chemistry and Chemical EngineeringShangqiu Normal UniversityShangqiu476000P.R.China

Polyferrocene macrocycles hold immense potential in the fields of molecular electronics and electrochemistry,primarily due to their multiple metal ***,developing highly efficient synthetic strategies for constructing these rings remains a significant *** this study,we successfully synthesized triferrocenyl macrocycles using Pt-mediated coupling strategy and determined their configuration using single-crystal X-ray diffraction analysis,revealing a structure reminiscent of the Penrose *** comprehensively investigated the macrocycle’s structure,photophysical properties,and employed density functional theory(DFT)calculations to gain further ***,this macrocycle exhibits several advantageous features,including a flexible structure,good solubility,and a highly efficient synthetic pathway.

关键词： Conjugated macrocycle Organometallic macrocycle Pt-template method