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1.
Two kinds of Tb( Ⅲ ) complexes with tetrapodal ligand, [TbL(NO3)]^3+ and [TbL]^3+ (L: 1,1, 1', 1'-tera ( 2-pyridinecarboxylester )-di ( trimethylpropane)) were intercalated into the interlayer space of montmorillonite (MT) by ion exchange and coordination reaction of L with the Tb^3+ ion existing in the interlayer space of Tb-MT respectively. The obtained luminescent supramolecular composite materials, [ TbL (NO3) ]^2+-MT and [TbL]^3+-MT were characterized by elemental analysis, XRD, FT-IR, UV-vis and thermal analysis. At the same time, the luminescent properties of the materials were also studied. The results show that the intercalated materials with regular layered structure, good thermal stability and the interlayer spacing (d001) approximates to the size of the complex ions which are located in the interlayer space of MT in the form of a monolayer.  相似文献   

2.
The new ligand N-benzyl-2-{2’-[(benzyl-ethyl-carbamoyl)-methoxy]-dinaphthalene-2-yloxy}-N-ethyl-acetamide(L) and its complexes of rare earth picrates were synthesized.The complexes were characterized by elemental analysis,IR,UV-vis spectra and conductivity measurements.The fluorescence properties of the europium complex in solid state and CHCl3,ethyl acetone,acetonitrile and DMF were investigated.Under the excitation,the europium complex exhibited characteristic emissions of europium.The lowest triplet state energy level of the ligand indicated that the triplet state energy level of the ligand matched better to the resonance level of Eu(Ⅲ) than Tb(Ⅲ) ion.  相似文献   

3.
RbLn2F7(Ln = Gd, Y, Er, Yb and Lu), crystallized in the hexagonal RbEr2F7 structure type, is synthesized by a hydrothermal method. The excitation spectra of Eu^3 + -doped RbGd (Y)2F7 suggest that the oxygen content is very low in the samples obtained by hydrothermal synthesis. Only the f-f transitions of Gd^3+ ions are observed in the excitation spectrum of RbGd2F7:Eu^3+ (0.5mol%), while those of Eu^3+ ions do not appear. When the Gd^3+ ions are excited, the absorbed energy is transferred efficiently from Gd^3+ to Eu^3+ . The spectra show that the doped Eu^3+ ions are located in non-centrosymmetric sites in hexagonal RbLn2F7.  相似文献   

4.
Multiple Energy Transfers in Rare Earth Complex-Doped SiO2 Spheres   总被引:1,自引:0,他引:1  
Silica spheres doped with Eu (TTFA)3 and/or Sm(TTFA)3 were synthesized by using the modified Stober method. The transmission electron microscope image reveals that the hybrid spheres have smooth surfaces and an average diameter of about 210 nm. Fluorescence spectrometer was used to analyze the fluorescence properties of hybrid spheres. The results show that multiple energy transfer processes are simultaneously achieved in the same samples co-doped with Eu (TTFA)3 and Sm(TTFA)3, namely between the ligand and Eu^3+ ion, the ligand and Sm^3+ ion, and Sm^3+ ion and Eu^3+ ion. Energy transfer of Sm^3+→Eu^3+ in the hybrid spheres leads to fluorescence enhancement of Eu^3+ emission by approximately an order of magnitude. The lifetimes of the hybrid spheres were also measured.  相似文献   

5.
The layer-by-layer complexation technique of polymer and metal ion was successfully utilized to fabricate the uhrathin muhilayer film of poly(3-thiophene acetic acid (PTAA) and Tb^3 ion by dipping the substrates alternatively in polymer and Tb^3 ion aqueous solutions. UV - vis measurement revealed that the absorbance has linearity with the bilayer number from layer to layer and the X-ray photoelectron spectrum (XPS) confirmed the existence of Tb^3 ion. The pH of both the polymer and TbCl3 solutions influence the thickness dramatically while the concentration of the solutions is not so sensitive. The luminescent spectrum of the complex film shows the characteristic emission of Tb^3 ion as well as the ligand indicating the formation of the complex.  相似文献   

6.
The Y-Eu oxalate precursor was prepared with a homogeneous precipitation method. And the additives, Na2CO3, S, NaCl or their combination, were introduced into the precursor to prepare Y2O3 :Eu^3+ red phosphors at 1000 1300 ℃ for 2 h. The effect of molten salts on particle size and luminescent intensity was studied. The experimental results showed that the complex molten salt (Na:CO3 + S + NaCl) was conductive to enhance the luminescent intensity of Y2O3 :Eu^3+. The emission intensity of the phosphor prepared with these additives at 1300 ℃ was about 45% higher than that of the one prepared without molten salt, and about 11% higher than that of the corresponding commercial phosphor. Meanwhile, the particle size of Y2O3 :Eu^3+ phosphor was controlled effectively with the molten salt.  相似文献   

7.
Luminescence properties of nitride red phosphor for LED   总被引:1,自引:1,他引:0  
Eu^2+-doped ternary nitride phosphor, Sr2Si5N8:Eu^2+, was synthesized using the high temperature solid-state method. The X-ray diffraction (XRD) pattern showed that Sr2Si5N8 single phase was obtained. The lattice parameters shrank because the radius of Eu^2+ was smaller than that of Sr^2+. The emission spectra showed a broad emission band. With an increase in Eu^2+ concentration, the emission peak position was redshifted. The excitation spectra showed two excitation bands originating from the host and the 4f^7→4f^6 5d^1 transition of Eu^2+ ions Compared with the luminescent characteristic of Sr2Si5N8:Eu^2+ and CaS:Eu^2+ phosphors, at different temperatures, it was noted that the intensity of the two phosphors reduced gradually with an increase in temperature. The intensity of Sr2Si5N8:Eu^2+ phosphor was stronger than that of CaS:Eu^2+, which indicated that the luminescent characteristic of the former was better than that of the latter.  相似文献   

8.
Two dinuclear compounds [Ln2(acetate)6(H2O)4]-4H2O (Ln=Tb(1), Sm(2)) were obtained by the hydrothermal reaction of Ln2O3 with malonic acid at 150 ℃. Both compounds were characterized by elemental analyses, infrared spectra, and single crystal X-ray diffraction. The results showed that complexes 1 and 2 were isomorphous and crystallize in triclinic space group P 1. The coordination geometry around Ln(Ⅲ) ions in the complexes 1 and 2 was a distorted tricapped trigonal prism with a nine coordination. In the crystal, the molecular organization was further stabilized by well-defined weak hydrogen bonding interactions between the neutral dinuclear molecular units that led to the formation of a three-dimensional network. The fluorescence properties of the two complexes 1 and 2 in organic solvents were also studied. The results show that the ligand acetate favored energy transfer to the emitting energy level of Tb(Ⅲ) in complex 1. Some factors that influence the fluorescent intensity were also discussed in the article.  相似文献   

9.
The new phosphor calcium magnesium chlorosilicate, codoped with Eu^2+ and Dy^3+, was synthesized with the help of the high temperature solid state reaction in reducing atmosphere. The excitation and emission spectra were very similar to that of Ca8Mg(SiO4)4Cl2 :Eu^2+, and the Dy^3+ concentration influenced the emission intensity of this phosphor. The intensity of Eu^2+ and Dy^3+ codoped CMSC was stronger than that of Eu^2+ singly doped CMSC. The emission spectrum of the Dy^3+ ion overlapped the absorption band of the Eu^2+ ion, indicating that an energy transfer from Dy^3+ to Eu^2+ took place in CMSC:Eu^2+, Dy^3+ phosphor. The mechanism of the energy transfer from Dy^3+ tO Eu^2+, in this phosphor, might be resonant energy transfer.  相似文献   

10.
The bidentate phosphine oxide ligand 1,8-bis(diphenylphosphino) naphthalene oxide (NAPO) and its EuⅢ complex 1 Eu(TTA)3(NAPO) (TTA=2-thenoyltrifluoroacetonate) were chosen to study the effect of bidentate phosphine oxide ligand on the photophysical properties of the corresponding complex. The intramolecular energy transfer processes of 1 were studied. The investigation showed that with bidentate structure NAPO could suppress solvent-induced quenching by enforcing the ligand-ligand interaction and the rigidity of the complex. Contrasted with the monodentate triphenylphosphine oxide (TPPO), NAPO had a higher first triplet excited energy level (T1) and a lower first singlet excited energy level (S1), which fitted to the corresponding excited energy levels of anion ligand TTA much more and supported more efficient singlet and triplet energy transfer in its EuIII complex.  相似文献   

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13.
<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic  相似文献   

14.
正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,  相似文献   

15.
正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF  相似文献   

16.
正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure  相似文献   

17.
正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,  相似文献   

18.
正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.  相似文献   

19.
正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.  相似文献   

20.
正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.  相似文献   

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