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Preparation of TiAl/Ti_2AlC Composites with Ti/Al/C Powders by In-situ Hot Pressing

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Journal of Wuhan University of Technology(Materials Science) 2006年第2期21卷 14-16页

作者：梅炳初严明 State Key lab of Advanced Technology for Materials synthesis and Processing Wuhan University of Technology Wuhan 430070 China

TiAl/Ti2AlC composites were prepared by in-situ hot pressing of TilAl/C powders mixtures and sintered at different temperatures were investigated by X- ray diffraction （ XRD ） of samples. The reaction procedure of Ti-Al-C system could be divided into three stnges. Below 900℃ , Ti reacts with Al to form TiAl intermetallics ; above 900 ℃ , C reacts with remain Ti to form TiC triggered by the exothermal reaction of Ti and Al ; TiAl reacts with TiC to produce dense TiAl/Ti2AlC *** the holding stage, ternary Ti2AlC develops to layered polycrystal and composites pyknosis in the meanwhile. The mechanism of synthesis and microstructure was especially discussed.

关键词： Ti-Al-C system TiAl/Ti2AlC composites in-situ hot pressing microstructure

Porous Alumina Ceramics Fabricated by Spark Plasma Sintering

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Chinese Journal of Aeronautics 2006年第B12期19卷 257-260页

作者： WANG Kun FU Zheng-yi PENG Yong WANG Yu-cheng ZHANG Jin-yong ZHANG Qing-jie State Key lab of Advanced Technology for Materials synthesis and Processing Wuhan University of Technology Wuhan 430070 China

Porous alumina of regular spherical particles was fabricated with the spark plasma sintering （SPS） and then compared to those obtained through conventional hot pressing （HP）. The effects of the parameters of the heating process on porosity were also investigated, Microstructural studies suggest that porous ingots including regular pores be made out of regular spherical alumina particles due to the close sphere packages. A comparative study on the relative necks of the specimens produced by SPS and HP indicates an enhancement of neck growth with SPS. Contrasting the theoretical values to the experimental results over the relative necks indicates that a proper relationship between the relative necks and the porosity can be established by a sintering model.

关键词： spark plasma sintering (SPS) porous alumina ceramics sintering neck

Optimization of p-type Segmented Bi_2Te_3/CoSb_3 Thermoelectric Material Prepared by Spark Plasma Sintering

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Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 126-129页

作者：王军 State Key lab of Advanced Technology for Materials synthesis and Processing Wuhan University of Technology Wuhan 430070 China

A kind of p-type segmented Bi2 Te3/CoSB3 thermoetectric material was preparea oy sparse ptasma sintering（ SPS ） . When the segmented materials were used at the temperature ranging from 300 K to 800 K, the junction temperature was optimized, which is about 500 K, and the corresponding length ratio of CoSb3 to Bi2 Te3 is about 15 ： 2. The measured maximum power output of segmented materials is abont 320 W·m^-2, which is about 1.8 times as high as that of monolithic material CoSb3 under the same measuring conditions.

关键词： CoSb3 compounds bismuth telluride segmented thermoelectric materials power outpats

Recent developments in selective laser processes for wearable devices

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Bio-Design and Manufacturing 2024年第4期7卷 517-547页

作者： Youngchan Kim Eunseung Hwang Chang Kai Kaichen Xu Heng Pan Sukjoon Hong Optical Nanoprocessing lab Department of Mechanical EngineeringBK21 FOUR ERICA-ACE CenterHanyang University55 Hanyangdaehak-RoSangnok-GuAnsan 15588Republic of Korea Multiscale Manufacturing lab J.Mike Walker’66 Department of Mechanical EngineeringTexas A&M UniversityCollege StationTX 77843USA State Key laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058China

Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication *** have long been used to develop original solutions to such challenging technological problems due to their remote,sterile,rapid,and site-selective processing of *** this review,recent developments in relevant laser processes are summarized under two separate ***,transformative approaches,such as for laser-induced graphene,are *** addition to design optimization and the alteration of a native substrate,the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors,or the sequential addition of functional layers coupled with other electronic *** addition,the more conventional laser techniques,such as ablation,sintering,and synthesis,can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new ***,various wearable device components developed through the corresponding laser processes are discussed,with an emphasis on chemical/physical sensors and energy *** addition,special attention is given to applications that use multiple laser sources or processes,which lay the foundation for the all-laser fabrication of wearable devices.

关键词： Selective laser process Wearable device Transformative approach Laser-induced graphene Ablation Sintering synthesis

Derivative Spectroscopy and its Application at Detecting the Weak Emission/Absorption Lines

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Research in Astronomy and Astrophysics 2024年第3期24卷 205-223页

作者： Lihuan Yu Jiangdan Li Jinliang Wang Jiajia Li Jiao Li Qiang Xi Zhanwen Han Yunnan Observatories Chinese Academy of Sciences(CAS)Kunming 650011China Key lab of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened up unprecedented opportunities for stellar *** types of stars,such as early-type emission-line stars and those with stellar winds,can be distinguished by the profiles of their spectral *** this paper,we introduce a method based on derivative spectroscopy(DS)designed to detect signals within complex backgrounds and provide a preliminary estimation of curve *** method exhibits a unique advantage in identifying weak signals and unusual spectral line profiles when compared to other popular line detection *** validated our approach using synthesis spectra,demonstrating that DS can detect emission signals three times fainter than Gaussian ***,we applied our method to 579,680 co-added spectra from LAMOST Medium-Resolution Spectroscopic Survey,identifying 16,629 spectra with emission peaks around the Hαline from 10,963 *** spectra were classified into three distinct morphological groups,resulting in nine subclasses as follows.(1)Emission peak above the pseudo-continuum line(single peak,double peaks,emission peak situated within an absorption line,P Cygni profile,Inverse P Cygni profile);(2)Emission peak below the pseudo-continuum line(sharp emission peak,double absorption peaks,emission peak shifted to one side of the absorption line);(3)Emission peak between the pseudo-continuum line.

关键词： line identification-line profiles-methods data analysis-techniques spectroscopic-techniques radial velocities

ASYMMETRIC　synthesis　ⅩⅩⅧ:　ENANTIOSELECTIVE　REDUCTION　OF　AROMATIC　KETONES　CATALYZED　BY　NEW　CHIRAL　CATALYST-(4R,8R,9S)-CAMPHANE[8,9-b]-1,3,2-OXATHIOBOROLIDINE

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Chinese Chemical Letters 1996年第5期7卷 415-418页

作者： Yao Zhong Jiang Xiao Ming Feng Liu Zhu Gong Zhi Li Gut Su Yang Ai Qiao Mi (Union laboratory of Asymmetric synthesis,Chengdu Institute of Organic Chemistry,Chinese Academy of Sciences. Chengdu 610041.) Union lab. of Asymmetric synthesis Chengdu Inst. of Organic Chemistry Chinese Academy of Sciences Chengdu 610041

Abstract: (4R, 8R,9S)-Camphane[8, 9-b]-1,3,2-oxathioborolidine prepared from (1R,2S.3R)-3-mercapto-camphol with borane was used as catalyst in the enantioselective reduction of aromatic ketones: moderate enantioselectivities with e.e. 7.44%-51 04%have been obtained for aromatic ketones with 20% mol catalyst, 73 .78% e.e for ω-bromo acetophenone with 100% mol catalyst.

关键词： BORANE

synthesis and Characterization of a New Triple-layered PerovskiteKSr_2Nb_3O_(10 )and Its Protonated Compounds

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Journal of Wuhan University of Technology(Materials Science) 2002年第2期17卷 22-25页

作者：方亮 State Key lab. of Advanced Tech. For Mater synthesis and Processing Wuhan University of Technology Wuhan China

New layered perovskites, KSr2Nb3O10 and two new protonated niobates HSr2 Nb3O10·1.2H2O and HSr2Nb3O10,were synthesized by solid state reaction and ion-exchange reaction. These new compounds -were characterized by EPMA, AAS, XRD, IR, DTA and so on. The structure may be described as treble perovskite sheets [Sr2Nb3O10]- interleaved with K+ ,H3O + or H+. These new compounds are new members of the Dion-Jacob-sonseries with n=3 for the general formula M[An-1 NbnO3n+1], and their indexed X-ray powder diffraction data were first reported in the paper.

关键词： niobate peravskite structure ion exchange protonated

Partially reversible photochromic behavior of organic-inorganic perovskites with copper(II) chloride

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 710-715页

作者： Xiao-wei PAN Gang WU Mang WANG Hong-zheng CHEN State Key lab of Silicon Materials MOE Key Laboratory of Macromolecule Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

We report that the ultraviolet （UV） light induced photochromic behavior of layered organic-inorganic perovskite material of （C4H9NH3）2CuCl4, changed from yellow to brown after irradiation with UV light （10 mW/cm^2） and partially recovered through storage in the dark. （C4H9NH3）2CuCl4 exhibited two distinct absorption bands centered at 286 nm （band Ⅰ） and 384 nm （band Ⅱ）, which were attributed to the photo-induced exciton formed in 2D inorganic layers sandwiched by organic layers. The blue shift of band Ⅰ from 287 to 269 nm as well as the decrease of the intensity of band Ⅰ and band Ⅱ could be found when samples were irradiated under UV light for different length of time. The simultaneous weakening of the intensity of the N-H...Cl hydrogen bond as well as the vibration of the long Cu-Cl bond in the distorted CuCl6^4- octahedron could be detected from the Fourier transform infrared （FTIR） spectra, which resulted the change of charge distribution of the dissymmetric Cl-Cu...Cl bond and the resulting photochromic behavior.

关键词： Photochromic behavior Perovskite Organic-inorganic hybrid

Deoximation Reaction in Room Temperature Ionic Liquids under Mild Conditions

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Chinese Journal of Chemistry 2011年第9期29卷 1846-1850页

作者： Zhang, Xiaoxia Lu, Bin Wang, Xiaoguang Zhao, Jingxiang Cai, Qinghai Modern Experimental Center Key Lab for Design ＆ Synthesis of Functional＆ed Materials and Green Catalysis School of Chemistry and Chemical Engineering Harbin Normal University No. 1 Shida South Road Limin Development Zone Harbin Heilongjiang 150025 China

Deoximation in metal chloride ionic liquids based on 1-alkyl-3-methylimidazolium and triethylene ammonium cations, such as AmimBr（Cl）-MClx （A=ethyl, butyl, benzyl; M=Al, Fe, Cu, Sn and Zn; x=2, 3） and Et3NHCl-FeCl3 were investigated under mild conditions. Ferrate chloride ionic liquid was proved to be an effective catalyst for deoximation of cyclohexanone oxime, exhibiting high conversion of oximes and selectivity to cyclo- hexanone. Good performance for the deoximation of other oximes such as salicylald oxime, acetone oxime, benzo- phenone oxime, 4-nitrobenzald oxime, acetophenone oxime, 2-chlorobenzaldehyde oxime, Acetald oxime, 2-butanone oxime and （1R）-camphor oxime was also achieved with bmimBr-FeCl3 as catalyst and solvent. The de- oximation was determined to carry out via acid-catalytic hydrolysis and the reaction mechanism was proposed.

关键词： deoximation oxime ionic liquids solvent-free