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991.
Young Hae Roh Jong Woo Bae Gil Soo Nam Joong Hyup Kim Sung Hoon Kim Cheol Min Yoon 《合成通讯》2013,43(1):81-86
The reaction of 6-[1-Aza-2-(dimethylamino)prop-l-enyl]-5-iodo-1,3-dimethyluracil (3) with various olefins in the presence of a catalytic amount of Pd(OAc)2 and 1.5 equiv. of K2CO3 in DMF at 120 °C gave the pyrido[2,3-d]pyrimidine derivatives (5a-b and 7a-d) in moderate to high yield. 相似文献
992.
Dr. Chang‐Hyung Choi Jongmin Kim Jin‐Oh Nam Sung‐Min Kang Seong‐Geun Jeong Prof. Dr. Chang‐Soo Lee 《Chemphyschem》2014,15(1):21-29
Controllable generation of complex emulsions comprising exceptional features such as several compartments and shape anisotropy is becoming increasingly important. Complex emulsions are attracting great interest due to their significant potential in many applications, including foods, pharmaceuticals, cosmetics, materials, and chemical separations. Microfluidics is emerging as a promising route to the generation of complex emulsions, providing precise control over emulsion shape, size, and compartments. The aim of this Minireview is to mainly describe the progress of microfluidic approaches to design complex emulsions using hydrodynamic control and phase separation. The emulsions formed are classified according to their morphology, anisotropy, and internal structure. Emerging applications of complex emulsions formed using these microfluidic techniques are discussed. 相似文献
993.
N.P. Thuy N.A. Tuan N.N. Phuoc N.T. Nam T.D. Hien N.H. Hai 《Journal of magnetism and magnetic materials》2006
A systematic study of exchange bias in MnPd/Co and MnPd/Co1−xFex bilayers has been carried out. Very large unidirectional anisotropy constant of 2.2 erg/cm2 and the appearance of double-shifted loops, ascribed to the coexistence of positive and negative exchange bias, have been observed. The dependence of exchange bias, unidirectional anisotropy constant and coercivity on thickness, temperature, annealing regime and Fe content has been investigated and discussed. 相似文献
994.
S. Nam M.E. Davies M. Elad R. Gribonval 《Applied and Computational Harmonic Analysis》2013,34(1):30-56
After a decade of extensive study of the sparse representation synthesis model, we can safely say that this is a mature and stable field, with clear theoretical foundations, and appealing applications. Alongside this approach, there is an analysis counterpart model, which, despite its similarity to the synthesis alternative, is markedly different. Surprisingly, the analysis model did not get a similar attention, and its understanding today is shallow and partial.In this paper we take a closer look at the analysis approach, better define it as a generative model for signals, and contrast it with the synthesis one. This work proposes effective pursuit methods that aim to solve inverse problems regularized with the analysis-model prior, accompanied by a preliminary theoretical study of their performance. We demonstrate the effectiveness of the analysis model in several experiments, and provide a detailed study of the model associated with the 2D finite difference analysis operator, a close cousin of the TV norm. 相似文献
995.
996.
Quantification of homoegonol in rat plasma using liquid chromatography–tandem mass spectrometry and its pharmacokinetics application 下载免费PDF全文
Deok‐Gyu Hwang Eun Nam Kim Kyeong Lee Kyung‐Seop Ahn Sei‐Ryang Oh Hye Suk Lee 《Biomedical chromatography : BMC》2014,28(12):1816-1821
Homoegonol is a biologically active neolignan isolated from Styrax species with cytotoxic, antimicrobial, anti‐inflammatory and anti‐asthma activities. For the quantification of homoegonol in rat plasma, a selective and sensitive liquid chromatography–tandem mass spectrometric method was developed and validated for the first time using protein precipitation with methanol as a sample clean‐up procedure. The analytes were separated in an Atlantis dC18 column using a gradient elution of methanol and 0.1% formic acid, and mass‐to‐charge ratios were determined in selective reaction monitoring mode using tandem mass spectrometry with m/z 343.12 > 296.97 for homoegonol and m/z 517.30 > 282.90 for udenafil (internal standard). The standard curve was linear over the concentration ranges of 1 ? 500 ng/mL using a 30 μL rat plasma sample. The coefficient of variation and relative error for intra‐ and inter‐assay at four quality control levels were 3.9–10.0 and ‐3.3–2.7%, respectively. The overall recovery of homoegonol from rat plasma using protein precipitation was 99.7 ± 7.7%. The pharmacokinetics parameters of homoegonol were dose‐independent after both intravenous (1, 2.5 and 5 mg/kg doses) and oral (5, 10 and 20 mg/kg doses) administration in male Sprague–Dawley rats. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
D. S. Adamov V. V. Arabkin S. P. Besshapov K. V. Cherdyntseva A. P. Chubenko A. G. Duboviy P. A. Djatlov J. K. Janseitova V. V. Zhukov R. A. Nam N. M. Nesterova N. M. Nikolskaya V. P. Pavlyuchenko V. V. Piscal S. B. Shaulov A. Stepanov N. G. Vildanov L. I. Vildanova 《Il Nuovo Cimento C》1996,19(6):999-1003
Summary The combined (EAS+EC) ?Hadron? experiment was made at Tien-Shan Station during 1985–1991. A large statistic of gamma-hadron
families, combined with EAS, is now analysed. The result of the leader effect disappearance forN
e>107 was reported earlier and at this Conference too. Here we present new results about the existence of Super Young Showers (SYS)
with ageS<0.1, containing gamma-hadron families with visible energy ≥10 TeV. Namely, SYS have anomalous soft-energy spectra of particles
at gamma-hadron families. These events may be connected with Young Air Showers (YAS) and Narrow Air Showers (NAS).
Paper presented at the Special Session on very high-energy cosmic-ray interactions (superfamilies) of the XXIV International
Cosmic-Ray Conference, Rome, August 28–September 8, 1995. 相似文献
998.
Tunable Chirped Fiber Grating Based Variable Time-Delay Network for Phased-Array Antenna Beamforming
Jianliang Yang Yunqi Liu Swee Chuan Tjin Nam Quoc Ngo 《International Journal of Infrared and Millimeter Waves》2003,24(4):593-601
In this paper, we present a photonics continuous beamforming system for optically controlled phased-array antenna based on a tunable fiber ring laser source and a novel variable true-time delay network consisting of one single-mode fiber delay line and four tunable chirped grating delay lines. The chirp rate of each chirped grating is tuned by bending a uniform fiber Bragg grating (FBG) bonded at a slant onto the lateral surface of a simply supported beam. This kind of variable true-time delay network can provide five-channel time-delayed signals that can be fed to an antenna array to achieve continuously beam scanning. The proposed true-time-delay unit with 5-element phased array steerer is suitable for phased-array antenna beamforming at frequencies up to 12 GHz. 相似文献
999.
Fabrication and Characterization of Multi-layer Heat Mirror with Photocatalytic Properties 下载免费PDF全文
Tran Le Tuan Tran Huu Chi Nguyen Dac Ngoc Son Luu Minh Nam Hoang Dinh Quan Nguyen 《中国物理快报》2009,26(11):152-155
A novel TiO2(5)/TiO2(buffer)/Ti(4)/Ag(3)/Ti(2)/TiO2(1) multi-layer film coating with corning glass is designed and fabricated by a dc magnetron sputtering method as a renovation of the well-known TiO2/Ti/Ag/Ti/TiO2 system in order to obtain a heat mirror system with photocatalytic properties due to sufficient thickness of the Ti02 layer. The outer TiO2 layer is fabricated in two steps, possibly claimed as two layers TiO2(5) and TiO2(buuer), among which TiO2(buffer) the 70-nm-thick layer deposited in poor oxygen effectively minimizes the oxidation toward its neighbor Ti(4) layer. The optimal total thickness of the TiO2(5) and TiO(buffer) di-layer is found to be 300nm to yield a highly photo-catalytic property of the film without affecting the optical properties considerably. This multi-layer film can transmit light of above 75-85% in the visible spectrum (380 ≤ λ≤ 760 nm) and reflect radiation of above 90% in the infrared spectrum ( λ≥760 nm). Such multi-layer coatings are strongly recommended not only as promising transparent heat mirrors but also as photo-catalytic films for architectural window coatings. 相似文献
1000.
We have prepared the gallium oxide (Ga2O3) thin films on sapphire substrates by the metal organic chemical vapor deposition (MOCVD) technique. We have compared the two films with and without the thermal annealing by using the X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and the photoluminescence (PL) spectra. Postdeposition annealing of amorphous Ga2O3 films was found to increase the degree of crystallization and the surface roughness. The PL emission intensities of bands in the blue–green and the ultraviolet regions increased by the thermal annealing. 相似文献