63 resultados para Ni2
Resumo:
This letter demonstrates an alternative method to form gallium silicate glass ceramics using high-energy electron irradiation. Compared with glass ceramics obtained from the conventional thermal treatment method, the distribution and crystal sizes of the precipitated Ga2O3 nanoparticles are the same. An advantage of this method is that the spatial distribution of the precipitated nanoparticles can be easily controlled. However, optically active dopants Ni2+ ions do not participate in the precipitation during electron irradiation. (c) 2007 American Institute of Physics.
Resumo:
Two new azo dyes of alpha-isoxazolylazo-beta-dilcetones and their Ni(II) and Cu(II) complexes with blue-violet light wavelength were synthesized using a coupling component, different diazo components and metal (II) ions (Ni2+ and Cu2+). Based on the elemental analysis, MS spectra and FT-IR spectral analyses, azo dyes were unequivocally shown to exist as hydrazoketo and azoenol forms which were respectively obtained from the solution forms and from the solid forms. The action of sodium methoxide (NaOMe) on azo dyes in solutions converts hydrazoketo form into azoenol form, so azo dyes are coordinated with metal (II) ions as co-ligands in the azoenol forms. The solubility of all the compounds in common organic solvents such as 2,2,3,3-tetrafluoro-1-propanol (TFP) or chloroform (CHCl3) and absorption properties of spin-coating thin films were measured. The difference of absorption maxima from the complexes to their ligands was discussed. In addition, the TG analysis of the complexes was also determined, and their thermal stability was evaluated. It is found that these new metal (II) complexes had potential application for high-density digital versatile disc-recordable (HD-DVD-R) system due to their good solubility in organic solvents, reasonable and controllable absorption spectra in blue-violet light region and high thermal stability. (c) 2004 Elsevier B.V. All rights reserved.
Resumo:
Thiazolyl heterocyclic azo dye and its metal (Ni2+, Co2+)-azo complexes were synthesized. Their structures were confirmed by elemental analysis, UV-VIS absorption spectra, FT-IR, H-1 NMR and MALDI-MS. The thermal properties of metal complexes were studied by DSC-TGA. The optical constants (complex refractive index N=n + ik) and thickness of the complex thin films on polished single-crystal silicon substrates were investigated on a scanning ellipsometer. Results indicate that thiazolyl metal-azo complexes possess good optical and thermal properties. They would be a promising recording medium candidate for NVD with the Super-resolution near field structure (Super-RENS) technology. (c) 2007 Elsevier B.V. All rights reserved.
Resumo:
The emission intensity of Ni2+ at 1200 nm in transparent ZnO-Al2O3-SiO2 glass ceramics containing ZnAl2O4 nanocrystals is improved approximately 8 times by Cr3+ codoping with 532 nm excitation. This enhanced emission could be attributed to an efficient energy transfer from Cr3+ to Ni2+, which is confirmed by time-resolved emission spectra. The energy transfer efficiency is estimated to be 57% and the energy transfer mechanism is also discussed. (C) 2008 Optical Society of America.
Resumo:
The near-infrared emission intensity of Ni2+ in Yb3+/Ni2+ codoped transparent MgO-Al2O3-Ga2O3-SiO2-TiO2 glass ceramics could be enhanced up to 4.4 times via energy transfer from Yb3+ to Ni2+ in nanocrystals. The best Yb2O3 concentration was about 1.00 mol%. For the Yb3+/Ni2+ codoped glass ceramic with 1.00 mol% Yb2O3, a broadband near-infrared emission centered at 1265 nm with full width at half maximum of about 300 nm and lifetime of about 220 mu s was observed. The energy transfer mechanism was also discussed. (C) 2008 Optical Society of America.
Resumo:
Transparent Ni2+-doped MgO-Al2O3-SiO2 glass ceramics without and with Ga2O3 were synthetized. The precipitation of spinel nanocrystals, which was identified as solid solutions in the glass ceramics, could be favored by Ga2O3 addition and their sizes were about 7.6 nm in diameter. The luminescent intensity of the Ni2+-doped glass ceramics was largely enhanced by Ga2O3 addition which could mainly be caused by increasing of Ni2+ in the octahedral sites and the reduction of the mean frequency of phonon density of states in the spinel nanocrystals of solid solutions. The full width at half maximum (FWHM) of emissions for the glass ceramics with different Ga2O3 content was all more than 200 nm. The emission lifetime increased with the Ga2O3 content and the longest lifetime is about 250 mu s. The Ni2+-doped transparent glass ceramics with Ga2O3 addition have potential application as broadband optical amplifier and laser materials. (C) 2007 Elsevier Ltd. All rights reserved.
Resumo:
Transparent Ni2+-doped MgO-Al2O3-Ga2O3-SiO2-TiO2 glass ceramics were fabricated. The precipitated nanocrystal phase in the glass ceramics was identified by X-ray diffraction and transmission electron microscope. Broadband near-infrared emission centered at 1220 nm with full width at half maximum of about 240 nm and lifetime of about 250 mu s was observed with 980 nm excitation. The longer wavelength emission compared with Ni2+-doped MgAl2O4 crystal was attributed to the low crystal field occupied by Ni2+ in the glass ceramics. The present Ni2+-doped transparent glass ceramics may have potential applications in broadband optical amplifiers. (c) 2007 Elsevier B.V. All rights reserved.
Resumo:
Polycrystalline Zn1-xNixO diluted magnetic semiconductors have been successfully synthesized by an auto-combustion method. X-ray diffraction measurements indicated that the 5 at% Ni-cloped ZnO had the pure wurtzite structure. Refinements of cell parameters from powder diffraction data revealed that the cell parameters of Zn0.95Ni0.05O were a little bit larger than ZnO. Transmission electron microscopy observation showed that the as-synthesized powders were of the size similar to 60 nm. Magnetic investigations showed that the nanocystalline Zn0.95Ni0.05O possessed room temperature ferromagnetisin with the saturation magnetic moment of 0.1 emu/g (0.29 mu(B)/Ni2+). (c) 2005 Elsevier B.V. All rights reserved.
Resumo:
Nanocrystalline Zn0.95 - xNi0.05AlxO (x = 0.01, 0.02, 0.05 and 0.10) diluted magnetic semiconductors have been synthesized by an auto-combustion method. X-ray diffraction measurements indicate that all Al-doped Zn0.95Ni0.05O samples have the pure wurtzite structure. Transmission electron microscope analyses show that the as-synthesized powders are of the size 40 - 45 nm. High-resolution transmission electron microscope, energy dispersive spectrometer and X-ray photoemission spectroscope analyses indicate that Ni2+ and Al3+ uniformly substitute Zn2+ in the wurtzite structure without forming any secondary phases. The Al doping concentration dependences of cell parameters (a and c), resistance and the ratio of green emission to UV emission have the similar trends. (c) 2007 Elsevier B.V. All rights reserved.
Resumo:
IIYZ(D1-Y161)IIII(OEC) PSII LaCl3TbCl3Co2Ni2PSII 1. PSII , -PSII; 2. PSII , CaCl2Ca2+Mn3(III)>Mn(III)Mn(III)> Mn(III)Mn(IV) 3. LaCl3 TbCl3 IILa3+Tb3+IICa2+Ca2+ 10 mmol/L Ca2+50%50%PSII10 4Ni2Co2IINi2Co2II17 kDa23 kDaIICaCl25 mmol/L17 kDa10 mmol/L17 kDa 23 kDaMnCa
Resumo:
eIF2αHRI/,,eIF2αPoHRIHRIPCRPoHRI1-200cDNA,pET32aIPTG,Ni2+-NTA,PoHRI,PoHRIPoHRI
Resumo:
Ni2 + , RR -1 5 5V , 1 5 08 0 0mg L , , 0 998, 0 0 7mg L , , ; , ,
Resumo:
Eu~3Sm~3Mn~2Fe~3Co~2Ni~2ZnOcccc10Onm15357-366nmEu3+Sm3Mn2+Fe3Co2Ni2Zn2+O2- Eu3+ZnO363nm368nmEg=3.423.40evEu3Zn1-xEux0.005x0.15Zn1-xTMxO356nm-369nm3.34-3.46eVCo2d-dZn1-xCoxO60Zn1-xEuxO90Zn1-xEuxO613nmEu37F5D378nmZnO394nmEu3+5D07FJJ1234zno378nmEu3+5D07F2znoE4-400KZn0.9Eu0.1OznogCooIO23oK200KM-HBr021emgHc327OeZn0.9Mn0.1OZn0.9Ni0.1OZn0.9Co0.1O80KZn0.9Eu0.1OZT110K14.53Zn1-xTMxOCoFeNiMnZn1-xTMxO80Co2DMSsol-gelZnoTMMCM-41AAOZnO:TMMCM-41MCM-41AAoloonmMCM-41Zn0.9Co0.1O80K-30OKMnFeNiZnoAAOZnO:TM(TM=MnFeCoNiSOK-30OKZnO:AABuSmcoZnlxCoxOPH5ZnORERE=EuSmZn0.98Co0.02O80KZnOREREEuSm80K
Resumo:
ABBLaSr2Mn2O7CrTiNiFeMnBCr3Mn4Cr3crNi2Fe3MnLaS2Mn2O7MnMnMnFex0.2MR28OK74LasrZMn2O7Bi3+Sr2+x0.2Bi3Bi3TcoGdn=3Laca4kMn3O10La3-3xCa13xMn3O100.5x1.0La3x0.50.7x=0.8-1.0La3Mn3Mn3+Mn4+LaxCa4-xMn3O10x0-0.9Mn4x0.2x0.2xG-AFMx0.9C-AFM
