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31.
S Loser H Miyauchi JW Hennek J Smith C Huang A Facchetti TJ Marks 《Chemical communications (Cambridge, England)》2012,48(68):8511-8513
A solution-processed small molecule utilizing a novel 4,9-bis(2-ethylhexyloxy)naphtho[1,2-b:5,6-b']dithiophene "zig-zag" core (zNDT) exhibits high hole mobility, upshifted frontier MO energies, and enhanced photovoltaic cell short-circuit currents, fill-factors, and power conversion efficiencies (4.7%) versus the linear NDT isomer. 相似文献
32.
Photocatalytic Activity and Photo-Induced Wettability Conversion of TiO2 Thin Film Prepared by Sol-Gel Process on a Soda-Lime Glass 总被引:17,自引:0,他引:17
Watanabe Toshiya Fukayama Shigemichi Miyauchi Masahiro Fujishima Akira Hashimoto Kazuhito 《Journal of Sol-Gel Science and Technology》2000,19(1-3):71-76
We have developed the transparent photoactive TiO2 thin film coated on soda lime glass (SLG) by sol-gel process. Titanium dioxide thin films coated on SLG exhibit lower photocatalytic activity due to the thermal diffusion of Na ion from the SLG substrate. Thin SiO2 film precoating is very effective to prevent the thermal diffusion of Na ion. We have evaluated the photocatalytic decomposition of gaseous acetaldehyde and the photo-induced surface wettability of TiO2 films with and without SiO2 precoating layer. As expected, the TiO2 film on SiO2/SLG is more photoactive to decompose acetaldehyde than that on SLG. However, as for wettability conversion, there was little difference in the conversion rate between TiO2 film without SiO2, and TiO2 film with SiO2. Different dependence of Na ion diffusion on two kinds of photo-induced reaction on TiO2 is discussed based on the difference of the photo-induced reaction mechanism. 相似文献
33.
Yoshiaki Hidaka Takuji Nakamura Aya Miyauchi Toshihiko Shiraishi Hiroyuki Kawano 《国际化学动力学杂志》1989,21(8):643-666
Propyne (p-C3H4) or allene (a-C3H4) mixtures, highly diluted with Ar, were heated to the temperature range 1200–1570 K at pressures of 1.7–2.6 atm behind reflected shock waves. The thermal decompositions of propyne and allene were studied by both measuring the profiles of the IR emission at 3.48 μm or 5.18 μm and analyzing the concentrations of reacted gas mixtures. The mechanism and the rate constant expressions were discussed from both the profiles and the concentrations of reactant and products obtained. The rate constant expressions for reactions, (1) p-C3H4 → a-C3H4, (?1) a-C3H4 → p-C3H4, and (5) p-C3H4 + H → CH3 + C2H2 were evaluated. 相似文献
34.
WANG Mingxu H. Miyauchi T. Nakahata Y. Nishikawa Y. Oya N. Noda K. Okuno 《核工业西南物理研究院年报(英文版)》2004,(1):50-51
Boron is an attractive candidate of the first wall coating materials in fusion reactors. The behavior of deuterium implanted into boron films has been studied . This paper reports the effect of thin oxygen-containing boron layer on the behavior of deuterium im- planted into boron film by X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). 相似文献
35.
Photocatalytic activity of SrTiO3 codoped with nitrogen and lanthanum under visible light illumination 总被引:6,自引:0,他引:6
Miyauchi M Takashio M Tobimatsu H 《Langmuir : the ACS journal of surfaces and colloids》2004,20(1):232-236
Yellow SrTiO3 powders codoped with nitrogen and lanthanum (STO:N,La) were studied as visible light photocatalysts. The crystal phase of STO:N,La exhibited a pure perovskite phase, and O and Sr sites atoms were substitutionally doped with N and La atoms, respectively. The first principle calculation of STO:N,La indicated that the edge of the N(2p) band is situated above the valence band, which consisted of O(2p) orbitals, and the La orbitals did not exist in the band gap of SrTiO3. STO:N,La exhibited a higher oxidation activity of gaseous 2-propanol under vis illumination than SrTiO3 doped only with nitrogen (STO:N). The high activity of STO:N,La was due to the decrease in the oxygen vacancies, which acted as electron-hole recombination centers, because codoping with La3+ and N3- ions maintained the charge balance. The optimum doping density of N and La for visible light activity was 0.5%, and STO:N,La(0.5%) had an activity under UV illumination similar to pure SrTiO3. 相似文献
36.
An efficient template-directed photoligation of oligodeoxynucleotide (ODN) using 7-deaza-2′-deoxyadenosine derivative VZA is described. When ODN containing VZA at the 5′ end was photoirradiated with ODNs containing a pyrimidine base at the 3′ end in the presence of template ODN, rapid and efficient ligation (cycloaddition reaction) was observed without any byproduct formation. ODNs containing VZA showed an extremely high reactivity as compared with those reported in previous photoligations. 相似文献
37.
Toshiko Watanabe Chiemi Miyagi Yasuoki Murakami 《Journal of heterocyclic chemistry》1993,30(1):217-224
To confirm the structure of ethyl 9-methoxybenz[f]indole ( 8a ) prepared from ethyl pyrrole-2-carboxylate ( 4 ) via a new synthetic route, the following chemical correlation work was performed. Ethyl 9-methoxybenz[f]in-dole ( 8a ) was converted to 1-benzyl-3-methyl-5,6,7,8-tetrahydrobenz[f]indole ( 25 ), which was alternatively and authentically synthesized from ethyl 3-methylpyrrole-2-carboxylate ( 11 ). On the basis of the established route to the benz[f]indole nucleus, two representative benz[f]indoles, benz[f]indole ( 1 ) and 4,9-dioxobenz[f]indole ( 26 ) were synthesized. 相似文献
38.
The 1 H NMR assignment of oligomeric grafts of maleic anhydride (MA)‐grafted polyolefin (PO), MA‐g‐PO hereafter, was experimentally demonstrated for the first time using NMR spectroscopy. 13 C DEPT, 1 H‐1 H DQF‐COSY, and 1 H T2‐edited spectroscopy of MA‐g‐PO proved that peaks of the intermediate methine protons of succinic anhydride oligomeric grafts, which are nearly tetrameric, are observed at 2.5–3.5 ppm and show broadening. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
39.
[reaction: see text] 9-Tosyl-3,4-dihydro-beta-carboline (1) reacted with a ketone in the presence of (S)-proline as a catalyst to give the corresponding addition product in good yield and high enantioselectivity. In the process, a small amount of water was found to affect the stereoselectivity of the products. The system was applied to reaction of compound 1 and 3-buten-2-one to give 3,4,6,7,12,12b-hexahydro-1H-indolo[2,3-a]quinolizin-2-one, which is a versatile precursor for the synthesis of some indole alkaloids. 相似文献
40.
Noriyuki Miyauchi Isamu Kirikihira Xin Li Mitsuru Akashi 《Journal of polymer science. Part A, Polymer chemistry》1988,26(6):1561-1571
Graft copolymers were synthesized by the esterification reaction between acrylic copolymers and carboxyl group terminated vinylpyrrolidone oligomer using phase transfer catalysts. Acrylic copolymers were obtained by the radical copolymerization of β-bromoethyl methacrylate, chloromethylstyrene or glycidyl methacrylate with methyl methacrylate. Hydrophilic oligomers were prepared by the radical oligomerization of vinylpyrrolidone using β-mercaptopropionic acid as chain transfer agent. The degree of esterification increased with decreasing the molecular weight of oligomer and with increasing the number of potential grafting sites on polymer backbones. The water dispersibility of graft copolymers increased with increasing the nitrogen content and was therefore dependent on the branch oligomer content. 相似文献