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1.
Eu^2+和Mn^2+在Sr3MgSi2O8中的光致发光研究   总被引:8,自引:1,他引:7  
研究了Eu^2+和Mn^2+共激活的Sr3MgSi2O8的荧光性质。Eu^2+和Mn^2+在460nm和690nm的发射峰分别由Eu^2+的5d→4f跃迁和Mn^2+的^4T1(^4G)→^6A1g(^6S)跃迁产生。未观察到单掺杂Mn^2+的Sr3MgSi2O8的荧光发射,而掺入Eu^2+后则出现了Mn^2+的690nm光致发光峰,表明Eu^2+对Mn^2+有敏化作用。Eu^2+的荧光寿命也受M  相似文献   

2.
ELECTRON TRANSFER BETWEEN Eu~(3+) AND Ce~(3+) IN SrMgF_4 MATRIXELECTRONTRANSFERBETWEENEu~(3+)ANDCe~(3+)INSrMgF_4MATRIX¥YingWU;Ch...  相似文献   

3.
一种新的单基双掺稀土三基色荧光粉SrB_4O_7:Eu,Tb体系光谱特征高勇,石春山(中国科学院长春应用化学研究所稀土化学与物理开放实验室,130022)硼酸盐荧光材料是近年来引人注目的一类光致发光材料,分别以Tb3+,Eu2+为激活剂可以得到高效的灯...  相似文献   

4.
SYNTHESISOFALPO_4-12MOLECULARSIEVEFROMNON-AQUEOUSSYSTEMS¥QiuMingGAO;ShouGuiLIandRuRenXu(KeyLaboratoryofInorganicHydrothermalS?..  相似文献   

5.
SHIP-IN-BOTTLESYNTHESISANDCHARACTERIZATIONOFRu_4H_4(CO)_(12)ENTRAPPEDWITHINNaYZEOLITEAnMingLIU;YiDeXu;TakafumiSHIDO;MasaruICHI?..  相似文献   

6.
Eu^2+和Mn^2+在SrMgP2O7中的光致发光及其能量传递   总被引:1,自引:1,他引:0  
研究了Eu^2+、Mn^2+共激活的SrMgP2O7的发光性质、浓度与荧光性质的关系,Eu^2+和Mn^2+的发射光谱分别在400nm及670nm附近,它们是Eu^2+的5d-4f跃迁和Mn^2+的^4T1(^4G)-^6A1g(^6S)跃迁发射,实验结果表明,Eu^2+对Mn^2+的荧光发射有较强的敏化作用,Mn^2+对Eu^2+的荧光寿命和强度也有显著影响。  相似文献   

7.
SYNTHESIS AND CRYSTAL STRUCTURE OF THE CLUSTER COMPOUND MoS_4Cu_2Ag(Ph_3P)_3Br.H_2O¥DeLiangLONG;XinQuanXIN(StaleKeyLaboratoryof?..  相似文献   

8.
室温或近室温条件下,2-氨基嘧啶(AP)与4种铜(Ⅱ)盐CuCl2.2H2O,CuBr2,CuSO4.5H2O,CuAc2,H2O发生固-固相化学反应,生成3类不同配位比(Cu/AP)分别为2:2、1:1和1:2)的2-氨基嘧啶合铜与合物,用元素分析,碘量法,电感耦合等离直读光谱、IR、XRD、UV、ESR等方法表征了固相反应产物,不同阴离子铜盐的结构是影响固相反应的主要原因。讨论了固相反应的过程  相似文献   

9.
Bi3+敏化的SrSiO3:Eu3+,Bi3+发光体的合成与发光   总被引:2,自引:0,他引:2  
本文采用高温固相扩散法合成出一种新的发光体SrSiO3:eU^3^+,Bi^3^+。研究了激活剂Eu^3^+与敏化剂Bi^3^+浓度变化与发光强度的关系。实验发现,组成为Sr0.817Li0.0915SiO3:Eu^3^+0.075,Bi^3^+的发光体其发光强度最大。给出了发光体SrSiO3:Eu^3^+,SrSiO3:Eu^3^+,Bi^3^+的激发光谱与发光光谱;测定了发光体的X射线粉...  相似文献   

10.
STUDIESOFFAR-INFRAREDSPECTRAANDSOLID-SOLIDPHASETRANSITIONIN[n-C_nH_(2n+1)NH_3]_2CuX_4LAYERCOMPOUNDSWITHn=7-12,16¥NingGUO(Depart?..  相似文献   

11.
phase diagrams of KCl-KBO2-K2CO3, K2MoO4-KBO2-K2CO3, and K2WO4-KBO2-K2CO3 ternary systems were studied by a calculation-experimental method and differential thermal analysis (DTA). The coordinates of ternary eutectics were determined to be E 1: 622°C, 8.5 mol % KBO2, 56.5 mol % KCl, and 35 mol % K2CO3; E 2: 710°C, 23 mol % KBO2, 43 mol % K2CO3, and 34 mol % K2MoO4; E 3: 710°C, 23 mol % KBO2, 43 mol % K2CO3, and 34 mol % K2WO4. The specific heats of melting of the eutectics were determined.  相似文献   

12.
The phase relations in the cross-section of the K2W2O7-K2WO4-KPO3 containing 15 mol% Bi2O3 were undertaken using flux method. Crystallization fields of K6.5Bi2.5W4P6O34, K2Bi(PO4)(WO4), Bi2WO6, KBi(WO4)2 and their cocrystallization areas were identified. Novel phase K6.5Bi2.5W4P6O34 was characterized by single-crystal X-ray diffraction: sp. gr. P−1, a=9.4170(5), b=9.7166(4), c=17.6050(7) Å, α=90.052(5)°, β=103.880(5)° and γ=90.125(5)°. It has a layered structure, which contains {K7Bi5W8P12O68} layers stacked parallel to ab plane and sheets composed by potassium atoms separating these layers. Sandwich-like {K7Bi5W8P12O68} layers are assembled from [W2P2O13] and [BiPO4] building units, and are penetrated by tunnels with K/Bi atoms inside. FTIR-spectra of K2Bi(PO4)(WO4) and K6.5Bi2.5W4P6O34 were discussed on the basis of factor group theory.  相似文献   

13.
K3InF6 is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K2InC10O10H6F9, K3InC12O14H4F18 and K3InC12O12F18. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. The two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K3InF6 by decomposition at high temperature. The crystal structure of K3InC12O14H4F18 is characterized by complex anions [In(CF3COO)4(OHx)2](5−2x)− and isolated [CF3COOH2−x](x−1)− molecules with x=2 or 1, surrounded by K+ cations. The crystal structure of K3InC12O12F18 is only constituted by complex anions [In(CF3COO)6]3− and K+ cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K2InC10O10H6F9 and K3InC12O12F18 were also performed at room temperature on pulverized crystals.  相似文献   

14.
Solubility in the Na2Cr2O7-(NH4)2Cr2O7-K2Cr2O7-H2O four-component water-salt system at 25, 50, and 75°C was studied for the first time. Phase field boundaries for individual salts and potassium and ammonium dichromate solid solutions, monovariant lines, and invariant points were determined. Experimental data were used to optimize the looped isohydric process of potassium dichromate preparation involving additional salts.  相似文献   

15.
The phase diagrams of the NaBO2-NaCl-Na2CO3, NaBO2-Na2CO3-Na2MoO4, NaBO2- Na2CO3-Na2WO4, and NaBO2-NaCl-Na2WO4 ternary systems were studied by a calculation-experimental method and differential thermal analysis. The coordinates of ternary eutectics were determined: E 1: 612°C, 16 mol % NaBO2, 42 mol % NaCl, and 42 mol % Na2CO3; E 2: 568°C, 12 mol % NaBO2, 28 mol % Na2CO3, and 60 mol % Na2MoO4; E 3: 575°C, 12 mol % NaBO2, 32 mol % Na2CO3, and 56 mol % Na2WO4; E 4: 628°C, 8 mol % NaBO2, 20 mol % NaCl, and 72 mol % Na2WO4; and E 5: 655°C, 9 mol % NaBO2, 53 mol % NaCl, and 38 mol % Na2WO4.  相似文献   

16.
马修臻  胡斌 《化学通报》2018,81(10):939-943,938
本文用高精度数字式振荡管密度计测定了288K至318K温度范围内Li2SO4 + Na2SO4 + H2O和 Li2SO4 + K2SO4 + H2O三元体系的密度。混合溶液的离子强度范围从0.1到4.5 mol.kg–1,混合溶液中Na2SO4和K2SO4的离子强度分数为0.2,0.4,0.6和0.8。用密度实验值拟合得到了不同温度下Pitzer离子相互作用模型混合参数θV和 ψV,模型的计算值与实验值的偏差在±0.002 g.cm3以内。用Pitzer模型计算了不同离子强度下三元体系的混合体积。  相似文献   

17.
Two compounds of formula La7A3W4O30 (with A=Nb and Ta) were prepared by solid-state reaction at 1450 and 1490 °C. They crystallize in the rhombohedric space group R-3 (No. 148), with the hexagonal parameters: , and , . The structure of the materials was analyzed from X-ray, neutron and electronic diffraction. These oxides are isostructural of the reduced molybdenum compound La7Mo7O30, which are formed of perovskite rod along [111]. An order between (Nb, Ta) and W is observed.  相似文献   

18.
The structural, electronic, and vibrational characteristics and energies of the isolated polyoxide clusters B20O30, Al20O30, V20O50, Si20O30H20, and Si20O30F20 and their complexes with the H ion and ammonia complexes Al20O30 · nNH3 have been calculated by the density functional theory B3LYP method with different basis sets. The computation results show that the symmetric closo structure I h with oxygen bridges located above the centers of the faces of an empty [M20] dodecahedron is more favorable for V20O50, Si20O30H20, and Si20O30F20. For B20O30, the cage closo isomer is also more favorable than the other isomers, but its structure is severely distorted as compared to a dodecahedron and has a symmetry close to C 3 . For Al20O30, the I h structure corresponds to a high-lying local minimum of the potential energy surface. For Al20O30, a set of unusual puckshaped isomers of symmetry C i , with different numbers of four-coordinate atoms IVAl and three-coordinate atoms IIIO, was localized; these structures are more than 90 kcal/mol more favorable than the dodecahedron I h . The most favorable isomer of Al20O30 contains twelve four-coordinate atoms IVAl and four five-coordinate atoms VAl. The energies of dissociation of the most favorable M20O30 clusters into the M2O3 (C 2v ) and M4O6 (T d ) fragments and, in the case of Al20O30, also into the Al8O12 (O h ) and Al12O18 (D 3d ) fragments, have been estimated. The conclusion has been drawn that these clusters can, in principle, exist and can be experimentally detected in the isolated state. Analogous calculations have been performed for ammonia complexes Al20O30 · nNH3 with n varying from 1 to 20. The effect of solvation on the relative stability of the dodecahedral and puckshaped isomers of the Al20O30 cluster is observed. The isomers with ammonia molecules in their first coordination sphere become much closer to one another on the energy scale; however, the dodecahedron remains a considerably less favorable intermediate. Original Russian Text ? O.P. Charkin, N.M. Klimenko, D.O. Charkin, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 4, pp. 624–635.  相似文献   

19.
SnSbBiS4-SnS and SnSbBiS4-Sn2Sb6S11 sections were studied by physicochemical methods (DTA, X-ray powder diffraction, microstructure observation, and microhardness measurements). These sections were found to be eutectic quasi-binary sections of the SnS-Sb2S3-Bi2S3 ternary system. Solid solution regions based on the initial components were found on either side of the sections. Alloys in the solid solution region are p-type semiconductors.  相似文献   

20.
We have studied the preparation and crystallographic structure of three perovskite-type compounds: Sr3Cr2WO9, cubic, the lattice parameter of which is a = 7.812Å; Ca3Cr2WO9, tetragonal, the lattice parameters of which are a = 5.408 Å and c = 7.635Å; and Ba3Cr2WO9, hexagonal, the lattice parameters of which are a = 5.691 Å and c = 13.957Å. We have compared these three structures and shown the relationship between the dimensions of the alkaline-earth metal and the existence of the different structures.  相似文献   

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