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Journal of Rare Earths 2013年第11期31卷 1059-1062页

作者：茹晶晶郭飞云陈建中 department of Chemistry Ningde Normal University College of Chemistry and Chemical Engineering Fuzhou University

Li2Y4-xEux（WO4）7-y（MoO4）y red-emitting phosphors were synthesized by solid state reaction and characterized by powder X-ray diffraction （XRD） and photoluminescence （PL） spectrum. The excitation spectra showed that the phosphors could be efficiently excited by near-UV light of 395 nm. When the relative molar ratio of Mo/W was 7：0, and the optimum doped concentration of Eu3＋was 2.8 mol, the phosphor showed strong red emission lines at 615 nm corresponding to the forced electric dipole 5D0→7F2 transition of Eu3＋. Compared with Na2Y2Eu2（MoO4）7 and K2Y2Eu2（MoO4）7, the fluorescence intensity of Li2Y1.2Eu2.8（MoO4）7 phosphor was the strongest. The CIE chromaticity coordinates of Li2Y1.2Eu2.8（MoO4）7 phosphor was calculated to be （0.66, 0.34）.

关键词： white LED luminescence phosphor rare earths

Synthesis and photoluminescence properties of Ca_3R_(2–x)WO_9:xEu^(3+)(R=Y, Gd) phosphors

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Journal of Rare Earths 2015年第2期33卷 135-139页

作者：茹晶晶秦小焕颜桂炀陈建中 department of Chemistry Ningde Normal University School of Chemistry and Pharmaceutical Sciences Guangxi Normal Univer-sity College of Chemistry and Chemical Engineering Fuzhou University

Ca3R2–xWO9：xEu^3＋（R=Y, Gd） red-emitting phosphors were prepared by solid state reactions. These samples were characterized by differential scanning calorimetry and thermogravimetry analysis（DSC-TGA）, X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, photoluminescence（PL） and field emission scanning electron microscopy（FE-SEM） analyses. The optimum sintering temperature for these phosphors was 1100 ℃, and the optimum sintering time was 2 h. The optimum doped concentration of Eu^3＋ in Ca3Y2–xWO9：xEu^3＋ and Ca3Gd2–xWO9：xEu^3＋ were x=1.5 and x=1.1, respectively. These phosphors could be excited by near-UV light of 394 nm and blue light of 465 nm, and showed strong red emission line at 612 nm（^5D0→^7F2）, which indicated that Ca3R2–xWO9：xEu^3＋（R=Y, Gd） were promising red candidates for white LED.

关键词： tungstate rare earth luminescence LED

A Theoretical Study on the Isomerization of HSOF System

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Chinese Journal of Structural Chemistry 2005年第3期24卷 319-323页

作者：陈文凯曹梅娟刘书红李奕李俊qian 杨迎春 departmentofChemistry FuzhouUniversity Fuzhou350002 China departmentofChemistry FuzhouUniversity Fuzhou350002 China／／StateKeyLaboratoryofStructuralChemistryFuzhou350002China departmentofEarthandEnvironmentalSciences ChengduUniversityofInformationTechnologyChengdu610041China

Ab initio Hartree-Fock theory at the aug-cc-pvtz level is used to investigate the equilibrium structures and isomerization of HSOF system. All of the transition states have been calculated and confirmed by the intrinsic reaction coordinate (IRC). Four equilibrium structures, HSOF, HOSF, SO(H)F and OS(H)F, are predicted in this paper. Though OSF2 has been observed experimentally, the present calculated results suggest that the linear form isomer, HOSF, is more stable than OS(H)F by 35.2 kJ/mol. The linear form HSOF and the branched SO(H)F isomer are more unstable and the computed relative energies are 318.3 and 510.0 kJ/mol, respectively with respect to HOSF isomer corrected with zero point vibrational energy.

关键词： HSOF isomerization transition-state quantum chemistry ab initio

A Theoretical Study on the Equilibrium Structures and Relative Stabilities of H_2SO

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Chinese Journal of Structural Chemistry 2005年第1期24卷 104-108页

作者：陈文凯杨迎春李俊汉叶芝祥杨怀金 department of Chemistry Fuzhou University Fuzhou 350002 ChinaState Key Laboratory of Structural Chemistry Fuzhou 350002 China department of Earth and Environmental Sciences Chengdu University of Information Technology Chengdu 610041 China

MP2 and DFT/B3LYP calculations with Aug-cc-pvTz and Aug-cc-pvQz basis set levels are used to investigate the equilibrium structures and isomerization of H2SO isomers. All of the transition states have been calculated and confirmed by the intrinsic reaction coordinate (IRC). The calculated results show that H2SO isomers have three equilibrium structures and the linear structure is the most stable while the branched H2OS is the most unstable (the relative energies are 0.0, 82.1 and 155.3 kJ/mol for HSOH, H2SO and H2OS, respectively with the zero point vibrational energy correction at B3LYP/Aug-cc-pvQz level). It is difficult for the linear HSOH to convert to the branched H2SO and H2OS isomers due to the high activation energies (higher than ca. 200 and 160 kJ/mol, respectively). The predicted thermodynamic results also suggest that the linear structure is the most stable and may be the only species that can be found experimentally. The kinetic results demonstrate that the isomerization is a unimolecular one, and the reaction rate is slow.

关键词： H_2SO density functional theory isomerization transition-state theory

Dynamic characteristics of charged droplets in an electrostatic spraying process with twin capillaries

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2403-2411页

作者： Jun Zhang Hongzhou He Guanxing Huang Cleaning Combustion and Energy Utilization Research Center of fujian Province School of Mechanical Engineering Jimei University Engineering training Centre Jimei University

The experimental and simulated investigations on electrostatic spraying with twin capillaries are carried out. The starting electric voltage required for the cone-jet and the deposition characteristics of the droplets are *** whole spraying process, which includes jet and droplet motions, is simulated and the simulated results on the motions of jet and droplet are basically consistent with the experiments. According to the simulated results,the contributions of various electric forces to droplet movement are quantitatively analyzed and the droplet dynamic characteristics, especially the interaction mechanism between two sprays, are revealed. The test results on the droplet deposition characteristics partially support the simulated results on the droplet motion. The present work is useful for a better understanding on the interaction between sprays in double or multi-capillary system.

关键词： Electrostatic spray Twin capillaries Simulation Interaction

High-Precision Two-Dimensional Atom Localization in a Cascade-Type Atomic System

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Chinese Physics Letters 2014年第10期31卷 57-60页

作者：陈景东方玉宏张婷 College of Physics and Information Engineering Minnan Normal University Zhangzhou 363000 College of Chemistry and Environment Minnan Normal University Zhangzhou 363000

We investigate the behavior of two-dimensional （21）） atom localization in a three-level cascade-type atomic system via measuring the probe absorption. It is found that the precision of the atom localization can be improved by adjusting probe detuning and coupling a coherent coupling field and standing-wave fields to the same atomic transition. Remarkably, a single localization peak can be obtained by adjusting appropriate system parameters, and some corresponding explanations are also given.

关键词： ATOMS RESEARCH LOCALIZATION theory CASCADES (Fluid dynamics) STANDING waves ATOMIC transitions

A Zn(II) Metal-organic Framework Consisting of Hexagonal Cavities Constructed by Benzyl-functionalized 5-Aminoisophthalate

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Chinese Journal of Structural Chemistry 2015年第4期34卷 562-568页

作者：孙小飞尤俊明徐霞红李小菊 College of Chemistry and Chemical Engineering Fujian Normal University fujian Key Laboratory of Polymer Materials College of Materials Science and Engineering Fujian Normal University

The hydrothermal reaction of 5-benzylaminoisophthalic acid （H2BAIP） and Zn（CH3COO）2·2H2O in the presence of NaOH gave rise to a three-dimensional （3-D） metal-organic framework containing Zn（Ⅱ）-carboxylate chains, [Zn（BAIP）]n. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in trigonal space group R-3 with a = 28.354（2）, b = 28.354（2）, c = 8.3821（8） A, e = 120°, V= 5836.0（10） A^3, Z= 18, Mr = 334.62, Dc = 1.714 g·cm^3,μ = 1.909 mm^-1, S = 1.162, F（000） = 3060, the final R = 0.0785 and wR = 0.1121 for 2334 observed reflections （I 〉 2σ-（I））. Zn（Ⅱ） is in a distorted tetrahedral geometry, and BAIP serves as a μ4-bridge using two μ2,η^2-bridging carboxylate groups. BAIP links Zn（Ⅱ） ions into a 3-D network containing hexagonal cavities. The coordination-inert benzyl occupies the void space of the large hexagonal cavities. The complex is thermally stable up to 410℃, and exhibits photoluminescent emission at 522 nm on 402 nm excitation.

关键词： carboxylate ligand coordination polymer crystal structure photoluminescence

pH-Dependent Assembly of Molecular Capsule,2D and 3D Coordination Polymers

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Chinese Journal of Structural Chemistry 2011年第10期30卷 1483-1492页

作者：林榕光 department of Biology and Chemistry Engineering Fuqing Branch of Fujian Normal UniversityFuqing State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou

Three lanthanum/4-sulfocalix[4]arene complexes,namely,H2[（H4CAS）La（H2O）7]2· H2[（H4CAS）La（H2O）7]2·2C2H5OH·12H2O（1）,[H（H4CAS）La（H2O）5]·5H2O（2）and [（H4CAS）La-（H2O）4（NO3）La（H2O）5]·7H2O（3）,have been synthesized at different pH *** 1,which exhibits the structure of ＂molecular capsule＂ containing the guest of C2H5OH molecule,is formed at pH = *** pH = 2～3,a two-dimensional（2D）coordination polymer of 2 is *** increase of the pH value to 5 leads to the three-dimensional（3D）coordination polymer of *** data for 1：monoclinic,space group P21/n,a = 10.8743（16）,b = 25.957（4）,c = 15.863（2）,β = 94.763（2）°,V = 4462.1（11）3,Mr = 1160.87,Z = 4,F（000）= 2376,R = 0.0370 and wR = 0.0936;Crystal data for 2：tetragonal,space group P4/n,a = 11.6593（16）,c = 14.069（4）,V = 1912.5（6）3,Mr = 1114.81,Z = 2,F（000）= 1136,R = 0.0849 and wR = 0.1906;and those for 3：triclinic,space group P1,a = 10.4588（16）,b = 14.995（2）,c = 16.699（3）,α = 65.446（3）,β = 83.487（3）,γ = 73.305（3）°,V = 2281.6（6）3,Mr = 1367.76,Z = 2,F（000）= 1368,R = 0.0423 and wR = 0.1183.

关键词： 4-sulfocalixarene pH-dependent crystal structures

Effect of multi-walled carbon nanotube addition on the microstructures and mechanical properties of Ti(C,N)-based cermets

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Journal of Advanced Ceramics 2018年第1期7卷 58-63页

作者： P.WU S.C.LIU X.R.JIANG College of Chemistry and Materials Science Longyan University

The surface modification of multi-walled carbon nanotubes(MWCNTs) was carried out using plasma treatment. The microstructures of the prepared cermets with different additions of MWCNTs were investigated by scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy dispersive X-ray analysis(EDX), and X-ray diffraction(XRD). Mechanical properties such as transverse rupture strength(TRS), fracture toughness(K_(IC)), and hardness(HRA) were measured. The results showed that some reactive groups were successfully modified on the surface of MWCNTs, resulting in the improvement of dispersibility. Most of the amorphous carbons and impurities were peeled from the MWCNTs. Increasing MWCNT addition decreased the dissolution of tungsten, titanium, and molybdenum in the binder phase. The cermet with 0.5 wt% MWCNT addition showed the highest TRS and fracture toughness. The strengthening mechanisms were attributed to the finer grain size, the homogeneous microstructure, and the higher volume fraction of binder phase in the binder. The toughening mechanisms were characterized by bridging and pulling-out.

关键词： Ti(C,N)-based cermets microstructure mechanical property fracture toughness

Effect of yttrium addition on water-gas shift reaction over CuO/CeO_2 catalysts

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Journal of Rare Earths 2009年第3期27卷 412-418页

作者：佘育生李雷詹瑛瑛林性贻郑起魏可镁 National Engineering Research Center of Chemical Fertilizer Catalysts Fuzhou University

This paper presented a study on the role of yttrium addition to CuO/CeO2 catalyst for water-gas shift reaction. A single-step co-precipitation method was used for preparation of a series of yttrium doped CuO/CeO2 catalysts with yttrium content in the range of 0-5wt.%. Properties of the obtained samples were characterized and analyzed by X-ray diffraction （XRD）, Raman spectroscopy, H2-TPR, cyclic voltammetry （CV） and the BET method. The results revealed that catalytic activity was increased with the yttrium content at first, but then decreased with the further increase of yttrium content. Herein, CuO/CeO2 catalyst doped with 2wt.% of yttrium showed the highest catalytic activity （CO conversion reaches 93.4% at 250 ℃） and thermal stability for WGS reaction. The catalytic activity was correlated with the surface area, the area of peak γ of H2-TPR profile （i.e., the reduction of surface copper oxide （crystalline forms） interacted with surface oxygen vacancies on ceria）, and the area of peak C2 and A1 （Cu^0→←Cu^2＋ in cyclic voltammetry process）, respectively. Besides, Raman spectra provided evidences for a synergistic Cu-Ovacancy interaction, and it was indicated that doping yttrium may facilitate the formation of oxygen vacancies on ceria.

关键词： CuO/CeO2 catalyst water-gas shift yttrium cyclic voltammetry rare earths