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101.
Ana Paula A. Marques Marcos Takashi S. Tanaka Elson Longo Edson R. Leite Ieda Lucia Viana Rosa 《Journal of fluorescence》2011,21(3):893-899
SrMoO4 doped with rare earth are still scarce nowadays and have attracted great attention due to their applications as scintillating
materials in electro-optical like solid-state lasers and optical fibers, for instance. In this work Sr1−xEuxMoO4 powders, where x = 0.01; 0.03 and 0.05, were synthesized by Complex Polymerization (CP) Method. The structural and optical
properties of the SrMoO4:Eu3+ were analyzed by powder X-ray diffraction patterns, Fourier Transform Infra-Red (FTIR), Raman Spectroscopy, and through Photoluminescent
Measurements (PL). Only a crystalline scheelite-type phase was obtained when the powders were heat-treated at 800 °C for 2 h,
2θ = 27.8° (100% peak). The excitation spectra of the SrMoO4:Eu3+ (λEm. = 614 nm) presented the characteristic band of the Eu3 + 5L6 transition at 394 nm and a broad band at around 288 nm ascribed to the charge-transfer from the O (2p) state to the Mo (4d)
one in the SrMoO4 matrix. The emission spectra of the SrMoO4:Eu3+ powders (λExc. = 394 and 288 nm) show the group of sharp emission bands among 523–554 nm and 578–699 nm, assigned to the 5D1→7F0,1and 2 and 5D0→7F0,1,2,3 and 4, respectively. The band related to the 5D0→7F0 transition indicates the presence of Eu3+ site without inversion center. This hypothesis is strengthened by the fact that the band referent to the 5D0→7F2 transition is the most intense in the emission spectra. 相似文献
102.
Noriaki Suetake Hideaki Kawano Go Tanaka Hidenobu Hashikami Eiji Uchino 《Optical Review》2011,18(6):423-429
In this paper, a new image enlargement method applying the backprojection for lost pixel (BPLP) to the predefined codebook-based
method is proposed. BPLP is a method for image restoration. In BPLP, the eigenspace reflecting the characteristics of an input
image is generated from the remained pixels and is used to restore the missing pixels. In the proposed method, the eigenspace
is replaced by one generated from the predefined codebook (PDC). PDC represents edge-blurring properties in a small image
patch and consists of pairs of low- and high-frequency image patches on various edge patterns. By replacing the PDC-based
estimation of lost high-frequency components with BPLP, a fast image enlargement method retaining its performance can be developed.
Through some experiments, the effectiveness of the proposed method was demonstrated. Especially, it was confirmed that the
processing time of the proposed method was shortened to about 1/50 that of the PDC-based method. 相似文献
103.
Hidekazu Tanaka 《The Ramanujan Journal》2011,24(1):33-60
Kurokawa introduced q-multiple gamma functions and q-multiple sine functions. We show that the Appell’s O-function is expressed via the q-multiple gamma function. We also give some applications of this result. For example, we obtain a formula for the “Stirling
modular form” and calculate special values of the q-multiple sine function. Moreover, we give some formulas of Eisenstein series and double cotangent functions and its generalization.
Then the former gives an infinite product expression of the double sine function explicitly and a result of Kurokawa. 相似文献
104.
Teruo Tanaka 《Journal of Mathematical Analysis and Applications》2011,382(2):549-558
This paper concerns the optimal stopping problem for discrete time multiparameter stochastic processes with the index set Nd. In the classical optimal stopping problems, the comparisons between the expected reward of a player with complete foresight and the expected reward of a player using nonanticipating stop rules, known as prophet inequalities, have been studied by many authors. Ratio comparisons between these values in the case of multiparameter optimal stopping problems are studied by Krengel and Sucheston (1981) [9] and Tanaka (2007, 2006) [14] and [15]. In this paper an additive comparison in the case of finite stage multiparameter optimal stopping problems is given. 相似文献
105.
Ribeiro Geyse Adriana Corrêa da Rocha Cláudia Quintino Veloso William Barros Dantas Luiza Maria Ferreira Richter Eduardo Mathias da Silva Iranaldo Santos Tanaka Auro Atsushi 《Journal of Solid State Electrochemistry》2020,24(8):1759-1768
Journal of Solid State Electrochemistry - Rapid methods using batch injection analysis (BIA) with amperometric detection were developed for the determination of quercetin extracted from the... 相似文献
106.
Feng Gao Juan Song Bin Zhang Hidekazu Tanaka Fei Gao Weiwei Qiu Qingxiang Wang 《中国化学快报》2020,31(1):181-184
The core-shell structured Au@Bi2S3 nanorods have been prepared through direct in-situ growth of Bi2S3 at the surface of pre-synthesized gold nanorods.The product was characterized by X-ray diffraction,transmission electron microscopy and energy-dispersive X-ray spectroscopy.Then the obtained Au@Bi2S3 nanorods were coated onto glassy carbon electrode to act as a scaffold for fabrication of electrochemical DNA biosensor on the basis of the coordination of-NH2 modified on 5’-end of probe DNA and Au@Bi2S3.Electrochemical characterization assays demonstrate that the Au@Bi2S3 nanorods behave as an excellent electronic transport channel to promote the electron transfer kinetics and increase the effective surface area by their nanosize effect.The hybridization experiments reveal that the Au@Bi2S3 matrix-based DNA biosensor is capable of recognizing complementary DNA over a wide concentration ranging from 10 fmol/L to 1 nmol/L.The limit of detection was estimated to be 2 fmol/L(S/N=3).The biosensor also presents remarkable selectivity to distinguish fully complementa ry sequences from basemismatched and non-complementary ones,showing great promising in practical application. 相似文献
107.
Akio Urushima Daisuke Taura Makoto Tanaka Naomichi Horimoto Junki Tanabe Naoki Ousaka Tadashi Mori Eiji Yashima 《Angewandte Chemie (International ed. in English)》2020,59(19):7478-7486
A novel 2,6‐anthrylene‐linked bis(m‐terphenylcarboxylic acid) strand ( 1 ) self‐associates into a racemic double‐helix. In the presence of chiral mono‐ and diamines, either a right‐ or left‐handed double‐helix was predominantly induced by chiral amines sandwiched between the carboxylic acid strands with accompanying stacking of the two prochiral anthracene linker units in an enantiotopic face‐selective way, as revealed by circular dichroism and NMR spectral analyses. The photoirradiation of the optically active double helices complexed with chiral amines proceeded in a diastereo‐ (anti or syn) and enantiodifferentiating way to afford the chiral anti‐photodimer with up to 98 % enantiomeric excess when (R)‐phenylethylamine was used as a chiral double‐helix inducer. The resulting optically active anti‐photodimer can recognize the chirality of amines and diastereoselectively complex with chiral amines. 相似文献
108.
Hiroshi Takikawa Arata Nishii Hiromu Takiguchi Hirotoshi Yagishita Masato Tanaka Keiichi Hirano Masanobu Uchiyama Ken Ohmori Keisuke Suzuki 《Angewandte Chemie (International ed. in English)》2020,59(30):12440-12444
An intramolecular benzyne–phenolate [4+2] cycloaddition is reported. Benzyne precursors, having vicinal halogen‐sulfonate functionalities, linked with a phenol(ate) by various tether groups undergo efficient intramolecular [4+2] cycloaddition by treatment with either Ph3MgLi or nBuLi for halogen–metal exchange to form various benzobarrelenes. 相似文献
109.
Joji Tanaka Satu Hkkinen Parker T. Boeck Yidan Cong Sbastien Perrier Sergei S. Sheiko Wei You 《Angewandte Chemie (International ed. in English)》2020,59(18):7203-7208
An orthogonal combination of cationic and radical RAFT polymerizations is used to synthesize bottlebrush polymers using two distinct RAFT agents. Selective consumption of the first RAFT agent is used to control the cationic RAFT polymerization of a vinyl ether monomer bearing a secondary dormant RAFT agent, which subsequently allows side‐chain polymers to be grafted from the pendant RAFT agent by a radical‐mediated RAFT polymerization of a different monomer, thus completing the synthesis of bottlebrush polymers. The high efficiency and selectivity of the cationic and radical RAFT polymerizations allow both polymerizations to be conducted in one‐pot tandem without intermediate purification. 相似文献