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白光LED用荧光材料Ba3Gd(BO3)3∶Eu^(3+)的发光性能研究 总被引:1,自引:0,他引:1
用高温固相反应法制备了稀土离子Eu^3+掺杂的三元稀土硼酸盐Ba3Gd(BO3)3发光材料,通过X射线衍射(XRD)、荧光光谱和扫描电镜(SEM)等测试手段对Ba3Gd(BO3)3∶Eu^3+荧光粉的制备条件、发光性能以及形貌进行了研究。XRD结果表明,在1000℃时可得到Ba3Gd(BO3)3纯相。扫描电镜照片显示颗粒基本为球形,粒径约为200-400 nm。发光光谱测试表明,Ba3Gd(BO3)3∶Eu^3+荧光粉在近紫外区(UV)(396 nm)和蓝光区(466 nm)可以被有效地激发,分别用255和396 nm的紫外光激发样品时,以Eu3+的5D0-7F2(611和616 nm)超灵敏跃迁为主要发射峰。当Eu3+的掺杂浓度为10%(摩尔分数)时,Ba3Gd(BO3)3∶Eu3+在611和616 nm处的发光强度最大。因此,这种荧光粉是一种可能应用在白光LED上的红色荧光材料。 相似文献
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Crystal of Yb3+-doped Ba3Gd(BO3)3 has been grown by the Czochralski method. The spectroscopic characterizations have been investigated at room temperature. The Yb3+:Ba3Gd(BO3)3 crystal exhibits broad absorption at 976nm with FWHM of 7nm and large overall spitting of 2F7/2 manifold (823cm-1). The absorption and emission cross sections are 5.09×10-21cm2 at 976nm and 0.97×10-21cm2 at 1040nm,respectively. The fluorescence lifetime is 2.84 ms. 相似文献
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稀土高氯酸盐开环冠醚三缩乙二醇(EO_3)[La(C_6H_(14)O_4)_3(H_2O)](ClO_4)_3·H_2O,单斜晶系,P2_1/c空间群。晶胞参数为:a=15.474(2),b=11.386(1),c=20.841(4),β=99.82(1)°,V=3618(1),MoKα,Z=4,D_c=1.718g/cm3,μ=1.499mm ̄(-1)。全矩阵最小二乘精细修正,结构因子R=0.056,R_w=0.083。中心原子La与开环冠醚醚链上的O(1)~O(9)及一个水分子形成10配位双帽四方反棱柱结构。弱配体高氯酸根不参加配位。 相似文献
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JiChengCHU HongShengGUO JunBiaoCHANG KangZHAO 《中国化学快报》2004,15(7):785-786
The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N-methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final product was obtained in 20.8% yield. 相似文献
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1 INTRODUCTION To the present, the series of compounds M3Ln- (BO3)3 (M = Sr, Ba and Ln = La-Lu, Sc, Y) with space group P63cm or 3R have been reported[1~5]. Some of them exhibit interesting optical properties when doped into the active Cr3+ or Yb3+ ions as laser materials. For example, the Yb3+-doped Sr3Y- (BO3)3 crystal is a promising laser material for both tunable and femtosecond laser applications[6~8]. The Ba3Y(BO3)3 crystal melts congruently at 1256 ℃ and has a phase… 相似文献
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1 INTRODUCTION With the development of high power InGaAs laser diode (LD) as pump sources, the Yb3+-doped laser crystals have received much attention. Due to the simple energy level structure of the Yb3+ ions, the Yb3+-doped laser crystals have no concentration quenching, and have high quantum efficiency and low quantum defects even at high doping concentration of the Yb3+ ions[1, 2]. Therefore, the Yb3+-doped crystals are good candidates of media in the LD-pumped solid-state laser,… 相似文献
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《中国化学快报》2002,13(12):1227-1230
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微波辐照下(Bi_2O_3)_(0.8)(La_2O_3)_(0.2)固熔体对甲烷氧化偶联的催化行为陈长林,洪品杰,戴树珊,阚家德(云南大学化学系,昆明,650091)关键词微波,甲烷氧化偶联,(Bi_2O_3)_(0.8)(La_2O_3)_(0.2)甲烷氧化... 相似文献
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研究了Nd(ClO4)3·nH2O-bphsm[双(苯基亚砜)甲烷1体系(甲醇-氯仿1:2)和Er(ClO4)3·nH2O-bphsm体系(甲醇-氯仿1:2)的电子光谱。分析了在可见光区内,f一f跃迁的强度和强度参数,并从Nd3+和Er3+的超灵敏跃迁的振子强度和强度参数T2与配体bphsm浓度的关系,指出了体系中Nd与bphsm形成1:2.5的物种和Er3+与bphsm形成1:2的物种。 相似文献
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A novel hexanuclear copper-indium thiolate complex, [(InCl)2(OMe)(μ-OMe)2(μ- OMe)(μ-SPrn)2(CuPPh3)]2 1, was synthesized from the reaction of NaSPrn, InCl3 and [Cu(Me- CN)a][PF6] in the presence of Ph3P and characterized by single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P211n with a = 11.3533(8), b = 15.4939(11), c = 20.5189(14) A, β = 98.577(2)°, V = 3569.0(4) A3, Z = 2, C56H82Cl4Cu2In4O8P2S4, Mr = 1801.56, Dc = 1.676 g/cm3,μ(MoKa) = 2.213 mm^-1, F(000) = 1796, S = 0.985, the final R = 0.0559 and wR = 0.1099 for 8878 observed reflections with I 〉 2σ(I) and 367 variables. Complex 1 consists of two CuPPh3 fragments which symmetrically side-attach to the tetranuclear core of [InaCl4(OMe)2(μ-OMe)a(μ- OMe)2(μ-SPrn)4] by coordinating with sulfur atoms of propane-thio moieties. The average In-Ot (terminal), In-μ-O and In-μ3-O bond distances are 2.305(4), 2.144(4) and 2.294(4) A, respectively. 相似文献
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[(η^5—C5H4Si2Me5)(CO)(PPh3)2MoBr]络合物的合成 总被引:2,自引:0,他引:2
三羰基环戊二烯基卤钼络合物与三苯基膦或三乙基膦的反应有过研究,但都是单pph3配合,双pph3配合的溴钼络合物至今未见详细报道,本文通过三羰基(五甲基乙硅基)环戊二烯基溴钼络合物与三苯基膦反应制取双pph3配 相似文献
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采用高温固相反应合成了(Y,Gd)Al3(BO3)4中掺杂Ce^3 和Tb^3 的样品,并研究了其结构特性、光谱特性和发光过程中稀土离子问的能量传递。(Y,Gd)Al3(BO3)4属于三角晶系,具有R32的空间群,掺入Ce^3 ,Tb^3 杂质后晶格结构没有变化。(Y,Gd)Al3(BO3)4:Ce,Tb的激发光谱由3个宽谱带组成,这3个谱带分别对应于Ce^3 的4f-5d跃迁吸收。在该体系中存在Ce^3 →Tb^3 ,Gd^3→Tb^3 和Gd^3 →Ce^3 的能量传递,其中Ce^3 起敏化剂和中间体的双重作用。 相似文献
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Two Schiff base complexes [Cu(L)2] (1) and [Zn(L)2]·3H2O(2) of (E)-4-fluoro-2-((3-morpholino propylimino)methyl)phenol (HL) have been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. Crystal data for 1: triclinic, space group Pī with a=4.8000(10), b=11.109(2), c=13.921(3),α=66.55(3),β=80.35(3),γ=81.09(3)°, V=668.2(2)3 , Z=1, Dc=1.477g/cm 3 , F(000)=311, and the final R=0.0744 and wR=0.1601 for 2301 observed reflections with I > 2σ(I). And those for 2: monoclinic, space group P21 /c with a=14.789(3), b=11.713(2), c=18.846(4),β=107.85(3)°, V=3107.4(11)3 , Z=4, D c=1.389 g/cm 3 , F(000)=1368, and the final R=0.0749 and wR=0.1348 for 5423 observed reflections with I > 2σ(I). Both 1 and 2 are four-coordinated complexes, with a square-planar geometry of copper(Ⅱ) in 1 and a slightly distorted tetrahedral geometry of zinc(Ⅱ) in 2. An asymmetric unit consists of only one half of a Cu ion and one L ligand in 1, while an asymmetric unit is composed of one Zn ion, two L ligands and three water molecules in 2. Non-classical C-H···O and C-H F hydrogen bonds play important roles in the formation of a 1D chain of 1, but O-H O and O-H N hydrogen bonds play dominant roles in the self-assembly of a 3D network of 2. The antibacterial activities of 1 and 2 against B. subtilis, S. aureus, S. faecalis, P. aeruginosa, E. coli and E. cloacae have been evaluated by MTT method. 相似文献
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WANG Shufang GUO Tianying TAO Jian ZHENG Chenggang ZHANG Banghua SONG Cunjiang 《反应性高分子(英文版)》2005,14(1):1-7
Blends of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(butylene succinate-adipate) (PBSA), both biodegradable semicrystalline polyesters, were prepared with the ratio of PHBHHx/PBSA ranging from 80/20 to 20/80 by melt mixing method. Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), dynamic mechanical thermal analysis (DMA), polarizing optical microscopy (POM) and wide angle X-ray diffractometer (WAXD) were used to study the miscibility and crystallization behavior of PHBHHx/PBSA blends. Experimental results indicate that PHBHHx is immiscible with PBSA as shown by the almost unchanged glass transition temperature and the biphasic melt. 相似文献