scholarly journals Effect of Li+ doping on the luminescence performance of a novel KAlSiO4:Tb3+ green-emitting phosphor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Reziwanguli Yantake ◽  
Muyasier Kaiheriman ◽  
Taximaiti Yusufu ◽  
Aierken Sidike

AbstractA new green-emitting phosphor, KAlSiO4:1.5 mol% Tb3+, x mol% Li+, was prepared via a high-temperature solid-phase method, and its crystal structure, diffuse reflectance spectrum, and luminescence were studied. The results show that the Li+ doping shifts the strongest diffraction peak to a high angle direction, reducing grain size by 11.4%. The entry of Li2CO3 improves the luminescence performance of KAlSiO4:1.5 mol% Tb3+. At a Li+ concentration of 1.5 mol%, the sample has strong absorption in the ultraviolet light range from 250 to 400 nm. The luminous intensity of the sample at 550 nm approximately quadruples after Li+ doping. Additionally, the colour purity of the sample and the internal quantum yield increase to 83.3% and 42%, respectively. The sample changes colour with time when exposed to air without an obvious fading phenomenon. The emission intensity at 200 °C is 95.1% of its value at room temperature, indicating that the phosphor has excellent thermal stability when x = 1.5. These results show the feasibility of using the silicate phosphor for generating the green light component of white light-emitting diodes for solid-state lighting.

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Limin Dong ◽  
Jian Li ◽  
Qin Li ◽  
Lianwei Shan ◽  
Zhidong Han

The SrxBa1−xTiO3: Eu3+, Gd3+phosphors are synthesized by high temperature solid-phase method. Multiple techniques including X-ray diffraction (XRD), and scanning electron microscopy (SEM) are used to examine the surface morphology and structural properties of SrxBa1−xTiO3: Eu3+, Gd3+phosphors. The optical properties are presented and discussed in terms of photoluminescence (PL) and photoluminescence excitation (PLE) spectra. The as-obtained SrxBa1−xTiO3: Eu3+, Gd3+phosphors show higher PL emission intensity (at 591, 611 nm). The peaks at 591 and 611 nm are attributed to Eu3+  5D0-7F1,5D0-7F2. Gd3+has a strong sensitization on Eu3+. A certain amount of Sr2+and Ba2+is contributed to the intensity of light emission. After being irradiated with blue light, the phosphor samples emit yellow light. This suggests its potential applications in many fields.


Author(s):  
V.A. Artyukh ◽  
◽  
V.N. Borsch ◽  
V.S. Yusupov ◽  
S.Ya. Zhuk ◽  
...  

1988 ◽  
Vol 53 (11) ◽  
pp. 2914-2919 ◽  
Author(s):  
Pierrette Maes ◽  
Annie Ricouart ◽  
Emmanuel Escher ◽  
André Tartar ◽  
Christian Sergheraert

Analogs of angiotensin II in which phenylalanine in position 8 was replaced with cymantrenylalanine or with its triphenylphosphine photosubstitution product were synthesized by the solid-phase method. On rabbit aorta strips, these peptides were found to be pure antagonists of angiotensin II. Their relative affinities are higher than most other analogs substituted in position 8 with bulky amino-acids.


1991 ◽  
Vol 56 (2) ◽  
pp. 491-498 ◽  
Author(s):  
Bernard Lammek ◽  
Izabela Derdowska ◽  
Tomasz M. Wierzba ◽  
Witold Juzwa

In an attempt to determine some of the structural features in position 1 that account for V1 antagonism, four new analogues of arginine-vasopressin were synthesized and the effect of the modifications on the vasoconstrictor activity was checked using isolated mesenteric arterial vessels of rats. The protected precursors required for these analogues were synthesized by a solid phase method of peptide synthesis. One of the reported analogues, namely [1-(4-mercapto-4-tetrahydrothiopyraneacetic acid)., 2-O-methyltyrosine, 8-arginine]vasopressin appears to be a potent competitive antagonist of the vasoconstrictor effect by AVP.


1981 ◽  
Vol 362 (2) ◽  
pp. 833-840 ◽  
Author(s):  
Eric ATHERTON ◽  
Willy HÜBSCHER ◽  
Robert C. SHEPPARD ◽  
Vivienne WOOLLEY

2001 ◽  
Vol 10 (2) ◽  
pp. 89-92 ◽  
Author(s):  
T. Abiko ◽  
R. Ogawa

Two {Met(0)6}deacetyl-thymosin β4analogs containing Phe(4F) or Tyr(Me) at position 12 were synthesized by the manual solid-phase method, and their anti-inflammatory effect on carrageenin-induced edema in the mouse paw was studied. Fluorination of the para-position of Phe12resulted in a marked antiinflammatory effect on carrageenin-induced edema in the mouse paw compared with that of our synthetic {Met(0)6}deacetyl-thymosin β4, but the other analog, {Met(0)6, Tyr(Me)12}deacetyl-thymosin β4, showed a marked reduction of the anti-inflammatory effect.


1994 ◽  
Vol 59 (2) ◽  
pp. 461-466 ◽  
Author(s):  
Vladimir A. Basiuk ◽  
Taras Yu. Gromovoy

The "gas solid-phase" method is used for the preparation of both symmetric and asymmetric 2,5-dioxopiperazines via cyclization of vaporous linear dipeptides in the presence of silica.


2016 ◽  
Vol 680 ◽  
pp. 208-211
Author(s):  
Lian Lian Wu ◽  
Qiang Li ◽  
Dan Yu Jiang ◽  
Jin Feng Xia

In this paper, La0.65Sr0.35MnO3 (LSM) oxide powder with ultrafine structure has been synthesized by self-propagating combustion method. The powders were characterized by X-ray diffraction, scanning electron microscopy and laser size analysis. Compared to the powders prepared by traditional solid-phase method, the grain size of powders prepared by self-propagating combustion method is relatively small and uniform. Starting from ultrafine LSM powders, sensing electrode (SE) for NO2 mixed-potential sensors based on yttria-stablized zirconia (YSZ) was fabricated. As-obtained NO2 sensor displays fast response and high sensitivity (25.4mV/decade). The response values of the sensor have good linear relationship with the logarithm of NO2 concentration varying from 30ppm to 500ppm.Keywords:Self-propagating combustion method; La0.65Sr0.35MnO3; NOx sensor; YSZ


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