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261.
Byeong-Yun Oh Young-Jun Lee Sang-Jun Cha Kwang-Young Kim Gi-Seok Heo 《Journal of solid state chemistry》2011,184(9):2462-2465
The compositional dependence of co-sputtered tungsten indium zinc oxide (WInZnO) film properties was first investigated by means of a combinatorial technique. Indium zinc oxide (IZO) and WO3 targets were used with different target power. W composition ratio [W/(In+Zn+W)] was varied between 3 and 30 at% and film thickness was reduced as the sample position moved toward WO3 target. Furthermore, the optical bandgap energy increased gradually, which might be affected by the reduction in film thickness. All the WInZnO films showed an amorphous phase regardless of the W/(In+Zn+W) ratio. As the W/(In+Zn+W) ratio in WInZnO films increased, the carrier concentration was restricted, causing the increase in electrical resistivity. W cations worked as oxygen binders in determining the electronic properties, resulting in suppressing the formation of oxygen vacancies. Consequentially, W metal cations were effectively incorporated into the WInZnO films as a suppressor against the oxygen vacancies and the carrier generation by employing the combinatorial technique. 相似文献
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265.
This paper presents cold-rolling and annealing methods to obtain a high-magnetic induction in inhibitor-free 0.1-mm-thick 3% silicon–iron sheets containing 18 or 150 ppm sulfur. In case of the two-step cold-rolling, the sheets containing 150 ppm sulfur showed a strong {1 0 0} final texture at 400 °C/h, and some fraction of {1 1 0} component was observed at 25 °C/h. However, three-step cold-rolling resulted in a sharp {1 1 0}〈0 0 1〉 final texture at 25 °C/h. This is due to the difference in intensity ratio of {1 0 0}〈0 1 1〉 to {1 1 1}〈1 1 2〉 in the cold-rolling texture which influences the nucleation of {1 1 0}〈0 0 1〉 component and the selective growth kinetics of various grains. In case of 18 ppm sulfur, the final texture was mainly composed of a sharp {1 1 0}〈0 0 1〉 component even at 400 °C/h, due to the relatively low segregation concentration. 相似文献
266.
Two π-acidic chiral stationary phases (CSP 3, CSP 4) were prepared by connecting the N-3,5-dinitrobenzamide derivative or 2,4-dinitrobenzenesulfonamide derivative of (S)-leucinol to silica gel through the carbamate linkage. The CSPs were applied in resolving seven racemic N-acyl-1-naphthylaminoalkanes by chiral HPLC, and the chromatographic resolution results were compared. From the comparison of the resolution results of the two CSPs, the role of amide and sulfonamide group in each chiral selector of CSP 3 and CSP 4 and an iso-butyl and phenyl group on the chiral center of each CSP 2 and CSP 3 were explained. 相似文献
267.
A series of novel pyrazolo pyrimidinone derivatives (3(a–d), 4(a–d), and 6(a–d)) was synthesized from various pyrazolo amides (2a–d) which are synthesized by the reaction between ethyl 5-amino-3-methyl-1-phenyl-1H-pyrazole-4-carboxylate (1) and various lithium amides. In addition, we also described the synthesis of sclerotigenin drug molecule which has quinazoline moiety from simple 2-nitro benzoic acid with high yields. 相似文献
268.
Tae Jin Kim Nam Ho Heo Jong-Ho Kim Gon Seo 《Reaction Kinetics and Catalysis Letters》2003,79(2):287-293
Acetone cyclic triperoxide (ACTP) was formed over titania-incorporated mesoporous material catalysts from a mixture of acetone
and hydrogen peroxide under a mild and acid-free condition. Formation of ACTP was confirmed by single-crystal X-ray crystallography.
The formation of ACTP could be observed in this study because of using the catalyst with a large amount of titania-incorporation
at 23 wt.% and its large pore size.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
269.
Richard W. Heo 《Tetrahedron》2004,60(34):7225-7235
A substituted ferrocenophane, 1,1′-((1-tert-butyl)-1,3-butadienylene)ferrocene, was synthesized and polymerized via ring-opening metathesis polymerization (ROMP) to give soluble high molecular weight polymers with ferrocenylene units in the backbone. The monomer readily underwent polymerization upon exposure to a tungsten-based metathesis initiator, W(CHC6H4-o-OMe)(NPh)[OCMe(CF3)2]2 (THF), to give high molecular weight polymers (Mw=ca. 300,000). The molecular weights could be varied systematically by adjusting the monomer-to-catalyst ratio. UV/vis spectra revealed a bathochromic shift for the polymer, consistent with enhanced conjugation compared to the monomer. The polymer exhibited thermal properties similar to oligomeric poly(ferrocenylene). Cyclic voltammetry of the polymer suggested that the iron centers are coupled electronically. Upon doping with I2 vapor, the polymers displayed semiconducting properties (σ=10−5 S cm−1). Theoretical calculations were used to evaluate the nature of the bonding in these and related polymers. 相似文献
270.
A direct one-pot synthesis of phenanthrene lactams, which employs a Suzuki-Miyaura coupling/aldol condensation cascade reaction of isoindolin-1-one with 2-formylphenylboronic acid, has been developed. The approach is used to efficiently produce a number of natural aristolactams, such as aristolactam BII (cepharanone B), aristolactam BIII, aristolactam FI (piperolactam A), N-methyl piperolactam A, and sauristolactam. 相似文献