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Er^(3+)-Yb^(3+) codoped borosilicate glass for optical thermometry

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 848-851页

作者： FENG ZhiQing1,BAI Lan2.CAO BaoSheng1,GONG LiDong3 & DONG Bin1,4 1 School of Science,Dalian Nationalities University,Dalian 116600,china 2.College of Electromechanical & Information engineering,Dalian Nationalities University,Dalian 116600,china 3 School of Chemistry and chemical engineering,Dalian 11602.,china 4 institute of physics,Chinese academy of Sciences,Beijing 100190,china 1. School of Science Dalian Nationalities University Dalian 116600 China2. College of Electromechanical & Information Engineering Dalian Nationalities University Dalian 116600 China3. School of Chemistry and Chemical Engineering Dalian 116029 China4. Institute of Physics Chinese Academy of Sciences Beijing 100190 China

Infrared to green up-conversion emissions centered at the wavelengths of about 52. and 550 nm of the Er3+-Yb3+ codoped borosilicate glass are recorded,using a 978 nm semiconductor laser diode(LD) as an excitation *** fluorescence intensity ratio(FIR) of the green up-conversion emissions at about 52. and 550 nm in the Er3+-Yb3+ codoped borosilicate glass has been studied as a function of temperature over the temperature range of 2.5-873 *** maximum sensitivity and the temperature resolution derived from the FIR of the green up-conversion emissions are approximately 0.0038 K-1 and 0.2.K,*** is demonstrated that the prototype optical temperature sensor based on the FIR technique from the green up-conversion emissions in the Er3+-Yb3+ codoped borosilicate glass plays a major role in temperature measurement.

关键词： Er3+-Yb3+ codoped optical temperature sensor fluorescence intensity ratio

Crystallization behaviour and high coercivity of (Nd,Pr)_(13)Fe_(80)Nb_1B_6 melt-spun ribbons

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Rare Metals 2009年第3期28卷 253-256页

作者： GUO Pengju LIU Xincai PAN Jing XU Feng LI Yong CUI Ping Faculty of materials Science and chemical {2. Ningbo University Ningbo 315211 China institute of Solid State physics Chinese Academy of Sciences Hefei 230031 China Ningbo institute of materials of Technology and {2. Chinese Academy of Sciences Ningbo 315040 China

Amorphous （Nd,Pr）13Fe80Nb1B6 ribbons were crystallized at 670-730°C for 5-2. min to study the effects of isothermal crystallization on their behavior and magnetic properties. XRD results indicate that the isothermal incubation time is 12. 5, and less than 5 min at 670, 700, and 730°C, respectively. High coercivities, with the maximum value of iHc = 1616 kA/m at 700°C for 19 min, measured by a physical property measurement system, are obtained in the crystallized ribbons. This is mainly attributed to the addition of Pr and Nb, because Pr2.e14B has a higher anisotropic field than Nd2.e14B, and Nb enriched in the grain boundary regions can not only reduce the exchange-coupling effects among hard grains, but also impede grain growth during the crystallization process. In addition, it should also be related to the characteristics of the furnace that the authors designed.

关键词： Nd-Fe-B isothermal crystallization coercivity melt-spun ribbons Pr substitution

Theoretical study of the interaction mechanism of single-electron halogen bond complexes H_3C…Br-Y(Y=H,CN,NC,CCH,C_2._3)

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Science china Chemistry 2010年第1期53卷 216-225页

作者： LI ZhiFeng1,SHI XiaoNing1,TANG HuiAn1 & ZHANG JunYan2.1College of Life Science and Chemistry,Tianshui Normal University,Tianshui 741001,china 2.anzhou institute of {2. physics,Chinese academy of Sciences,Lanzhou 730000,china 1. College of Life Science and Chemistry Tianshui Normal University Tianshui 741001 China2. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The characteristics and structures of single-electron halogen bond complexes H3C…Br-Y(Y = H,CCH,CN,NC,C2.3) have been investigated by theoretical calculation *** geometries were optimized and frequencies calculated at the B3LYP/6-311++G *** interaction energies were corrected for basis set superposition error(BSSE) and the wavefunctions obtained by the natural bond orbital(NBO) and atom in molecule(AIM) analyses at the MP2.6-311++G *** each H3C…Br-Y complex,a single-electron Br bond is formed between the unpaired electron of the CH3(electron donor) radical and the Br atom of Br-Y(electron acceptor);this kind of single-electron bromine bond also possesses the character of a"three-electron bond".Due to the formation of the single-electron Br bond,the C-H bonds of the CH3 radical bend away from the Br-Y moiety and the Br-Y bond elongates,giving red-shifted single-electron Br bond *** effects of substituents,hybridization of the carbon atom,and solvent on the properties of the complexes have been *** strengths of single-electron hydrogen bonds,single-electron halogen bonds and single-electron lithium bonds have been *** addition,the single-electron halogen bond system is discussed in the light of the first three criteria for hydrogen bonding proposed by Popelier.

关键词： single-electron halogen bond single-electron hydrogen bond single-electron lithium bond MP2 DFT NBO AIM

Microstructure and Tribological Properties of TiB_2.TiB/TiN_x(x=1,0.3)/Ti Composite Coating Produced on Pure Ti by Laser Surface Alloying

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稀有金属材料与工程 2012年第S1期41卷 344-349页

作者： Guo Chun1,2.Chen Jianmin1,Zhou Jiansong1,Zhao Jierong1,2.Wang Lingqian1,2.Yu Youjun1,2.Zhou Huidi 1 1 Lanzhou institute of chemical {2.,Chinese academy of Sciences,Lanzhou 730000,china 2.Graduate University of Chinese academy of Sciences,Beijing 100039,china Chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China

TiB2.TiB/TiNx(x=1,0.3)/Ti composite coating was prepared on pure Ti by laser surface alloying by using powders of boron as starting *** composite coating was examined by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM)and scanning electron microscopy(SEM).The friction and wear properties of the composite coating were examined using a pin-on-disk tester under dry sliding wear *** results showed that the top surface of the composite coating was mainly composed of TiB2.TiB,TiN0.3,TiN and Ti phases,while the interface of the composite coating was composed of TiB and Ti *** composite coating showed sticklike structure near the top surface,and dendrites structure near the *** friction and wear test showed that the composite coating had better wear resistance than pure Ti due to their higher microhardness than that of pure Ti substrate.

关键词： pure Ti laser surface alloying TiB2 composite coating friction and wear property

Threading dislocation density comparison between GaN grown on the patterned and conventional sapphire substrate by high resolution X-ray diffraction

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG YuChao1, XING ZhiGang2. MA ZiGuang2. CHEN Yao2. DING GuoJian2. XU PeiQiang2. DONG ChenMing3, CHEN Hong2.& LE XiaoYun1 1 School of physics and Nuclear Energy engineering, Beihang University, Beijing 100190,{2. 2.Renewable Energy Laboratory, institute of physics, Chinese academy of Sciences, Beijing 100190,{2. 3 School of Information and Communication, Tianjin Polytechnic University, Tianjin 300160,{2. 1. School of physics and Nuclear Energy engineering Beihang University Beijing 100190 China2. Renewable Energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing 100190 China3. School of Information and Communication Tianjin Polytechnic University Tianjin 300160 China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. High resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2. which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

Photoresponsive organogel and organized nanostructures of cholesterol imide derivatives with azobenzene substituent groups

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Progress in Natural Science:materials International 2012年第1期22卷 64-70页

作者： Tifeng Jiao a,b,c,Yujin Wang a,Fengqing Gao a,Jingxin Zhou a,Faming Gao a a Hebei Key Laboratory of Applied Chemistry,College of Environmental and chemical engineering,Yanshan University,Qinhuangdao 066004,{2. b College of Chemistry & materials engineering,Wenzhou University,Wenzhou 32.02.,{2. c State Key Laboratory of Solid Lubrication,Lanzhou institute of chemical physics,Chinese academy of Sciences,Lanzhou 730000,{2. [a] Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China [b] College of Chemistry & materials engineering Wenzhou University Wenzhou 325027 China [c] State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Two new cholesterol imide derivatives with azobenzene substituent groups have been *** compounds possess headgroups of hydrogen or methyl units,*** gelation test revealed that a subtle change in the headgroup of azobenzene segment produced a dramatic change in the gelation behavior of both *** compound with headgroups of hydrogen units only gelated N,N-Dimethylformamide(DMF),while the other compound with headgroups of methyl units cannot gelate any solvent tested *** DMF gel and solution of the gelator,the reversible photoisomerization transitions by irradiation with ultraviolet(UV) and visible light are investigated by UV-vis absorption spectra,Fourier transform infrared spectrometer,scanning electron microscope,atomic force microscope,and X-ray diffraction *** UV irradiation of the gel,trans-cis photoisomerization of the azobenzene groups occurs,the change in molecular polarity leads to the breaking of van der Waals interactions,resulting in the gel-sol *** gel can be recovered by the reverse cis-trans photoisomerization after exposure to visible *** and spectral studies reveal that the gelator molecules selfassemble into one-dimensional fibers,which further crossed-linked to form regular *** results afford useful information for the development of new versatile low molecular mass gelators and soft matter.

关键词： Organogel Cholesterol Azobenzene Photoisomerization Soft material

Microstructure and Wear Resistance Evolution of HVOFSprayed WC-(W,Cr)_2.-Ni Coating with Post Heat Treatment In Air Atmosphere

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稀有金属材料与工程 2012年第S1期41卷 388-393页

作者： Hou Guoliang1,2.Zhou Huidi1,An Yulong1,2.Liu Guang1,2.Chen Jianmin1,Chen Jie1,2.1 State Key Laboratory of Solid Lubrication,Lanzhou institute of chemical {2.,Chinese academy of Sciences,Lanzhou 730000,china 2.Graduate University,Chinese academy of Sciences,Beijing 100049,china Chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

WC-(W,Cr)2.-Ni coating was prepared on 1Cr18Ni9Ti stainless steel and C-2.6 Ni-base Hastelloy by high velocity oxy-fuel(HVOF)*** effect of post heat treatment in air atmosphere on the microstructure,phase composition,microhardness,fracture toughness,and wear resistance of HVOF-sprayed WC-(W,Cr)2.-Ni coating was *** microstructure and phase composition of the coatings were analyzed by means of field emission scanning electron microscopy(FESEM)and X-ray diffraction(XRD).The microhardness and fracture toughness of the coatings were measured using a microhardness tester and a Vickers hardness ***,dry friction and wear behavior of the coatings sliding against Si3N4 ball was investigated using an oscillating friction and wear tester;and the worn surfaces of the coatings were analyzed by means of scanning electron microscopy(SEM).It was found that heat treatment within 500-800°C resulted in crystallization of amorphous phase in as-sprayed coating,generating nanoscale new phases such as NiWO4,CrWO4 and ***,heat treatment led to increase of the microhardness of as-sprayed coating,and the highest microhardness was obtained after heat treatment at 800°*** fracture toughness and wear resistance of the as-sprayed coating increased with increasing heat treatment temperature up to 700°C but tended to decrease with further elevating *** other words,the mechanical properties and wear resistance of the as-sprayed coatings were worsened owing to excessive growth of oxidation grains and depletion of ductile Ni binder after heat treatment above 700°*** it was suggested that as-sprayed ceramic composite coating should be post heat treated in air at a moderate temperature of 700°C so as to achieve the optimized mechanical properties and wear resistance.

关键词： HVOF WC-(W,Cr)2.-Ni coating post heat treatment microstructure wear resistance

Existence of the time periodic solution for damped Schrdinger-Boussinesq equation

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Communications in Nonlinear Science and Numerical Simulation 2000年第4期 179-183页

作者： Boling GUO and Xianyun DU (institute of Applied physics and Computational Mathematics,Beijing 100088,{2. Graduate School, Chinese academy of engineering physics, Beijing 100088,{2. Department of Mathematics, mianyang Normal College, mianyang 621.00,

In this paper, we study the time priodic solution for the weakly damped Schrodinger- Boussinesq equation, by Galerkin method, and prove the existence and unique- ness of the equations under some appropriate conditions.

关键词： Schrodinger- Boussinesq equation time priodie solution Galerkin met?

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4 1. Faculty of Physical engineering, Zhengzhou University, Zhengzhou 450052. china 2. Department of {2., Beijing Normal University, Beijing 100875, china 3. institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. institute of Modern {2., Fudan University, Shanghai 2.0433, china Faculty of Physical engineering Zhengzhou University Zhengzhou 450052 China Department of physics Beijing Normal University Beijing 100875 China institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China institute of Modern physics Fudan University Shanghai 200433 China

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.