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71.
Katsuhiro Nose Takahisa Omata Shinya Otsuka-Yao-Matsuo Hideaki Maeda 《Journal of luminescence》2007,126(1):21-26
The role of organic amines in the colloidal synthesis of CdSe quantum dots (QDs) has been studied. CdSe QDs were synthesized from the source solutions containing 5 vol% of amines having various alkyl chain lengths, stereochemical sizes and electron donation abilities. The role of the additional amines was evaluated on the basis of the photoluminescence (PL) properties such as PL wavelength and intensity of the obtained CdSe QDs. The observed PL spectra were explained by the fact that the amines behaved as capping ligands on the surface of the QDs in the product colloidal solution and complex ligands for cadmium in the source solutions. It was shown that the particle size was controlled by the diffusion process depending on the mass and stereochemical shape of the amines, and the luminescence intensity increased with the increasing electron donation ability and capping density of the amines. 相似文献
72.
Harayama Y Yoshida M Kamimura D Kita Y 《Chemical communications (Cambridge, England)》2005,(13):1764-1766
The use of hypervalent iodine(III) reagents allowed us to develop the novel and efficient direct synthesis of N,O-acetal compounds via the oxidative fragmentation reaction of alpha-amino acids or alpha-amino alcohols; furthermore, we succeeded in developing an improved synthesis of the key intermediate of discorhabdins. 相似文献
73.
Harayama T Yasuda H Akiyama T Takeuchi Y Abe H 《Chemical & pharmaceutical bulletin》2000,48(6):861-864
6H-Dibenzo[b,d]pyran-6-one, 6H-benzo[d]naphtho[1,2-b]pyran-6-one, and their derivatives were prepared via the palladium mediated aryl-aryl coupling reaction of aryl ortho-halobenzoate. The short step synthesis of arnottin I(1) was achieved by this method. 相似文献
74.
Oikawa M Saito T Takahisa K Suga Y Kino K Nakagawa T Tohei T Abe K Ueno H 《Physical review letters》2000,84(11):2338-2341
Out of plane measurements of the angular correlations for the 12C(e, e(')n) reaction have been performed for the first time in the giant resonance region. The cross sections were directly separated into the longitudinal and transverse, longitudinal-transverse, and transverse-transverse components. The cross section at the peak of the giant resonance ( omega = 22.5 MeV) has been found to be almost all longitudinal. It was reproduced by the multipole expansion with E0 and E2 components besides E1. The longitudinal-transverse component might have a maximum around 24 MeV. The transverse-transverse component is very small over the giant resonance. 相似文献
75.
76.
Mizu M Koumoto K Anada T Matsumoto T Numata M Shinkai S Nagasaki T Sakurai K 《Journal of the American Chemical Society》2004,126(27):8372-8373
A beta-(1 --> 3)-d-glucan schizophyllan (SPG) forms a stoichiometric complex with some polynucleotides. This communication describes our attempt to apply the SPG complex to deliver CpG DNA to endosomes to enhance cytokine secretion. To increase cellular uptake, we introduced spermine, arginine-glycine-aspartic acid tripeptide, octaarginine, or cholesterol to the SPG side chain. The chemically modified SPG showed essentially no cytotoxicity. When CpG DNA complex made therefrom was exposed to macrophages, dramatic enhancement in the cytokine secretion was observed. It increased 5-10 times from the naked dose and 100 times from the background. This performance promises that SPG can be an excellent carrier for CpG DNA. 相似文献
77.
Takeuchi Y Azuma K Abe H Sasaki K Harayama T 《Chemical & pharmaceutical bulletin》2002,50(7):1011-1012
The stereo structure of piperidine lactone (3), an intermediate of the antimalarial agent febrifugine ((+)-1) prepared by a synthetic method, was re-revised to the cis-form from the trans-form. 相似文献
78.
79.
Masashi Harada Masayuki Ohya Takahisa Suzuki Daisuke Kawaguchi Atsushi Takano Yushu Matsushita 《Journal of Polymer Science.Polymer Physics》2005,43(10):1214-1219
Three poly(4‐trimethylsilylstyrene)‐block‐polyisoprenes (TIs), the molecular weights of which were 82,000, 152,000 and 291,000 (TI‐82K, TI‐152K, and TI‐291K), were synthesized by sequential anionic polymerizations. The component polymers were a miscible pair that presented a lower critical solution temperature phase diagram if blended. The TI phase behavior was investigated with transmission electron microscopy. The order–disorder transition could be observed at a temperature between 200 °C (the ordered state) and 150 °C (the disordered state) for the block copolymer TI‐152K. The block copolymer TI‐82K presented the disordered state at 200 °C, whereas TI‐291K was in the ordered state at 150 °C. With the Flory–Huggins interaction parameter between poly(4‐trimethylsilylstyrene) and polyisoprene, which was evaluated by small‐angle neutron scattering for the block copolymers, the TI phase behavior could be reasonably explained by mean‐field theory. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1214–1219, 2005 相似文献
80.
Yoshimoto Abe Akira Kaijou Nobuhiro Shintani Yukinori Nagao Takahisa Misono 《Journal of polymer science. Part A, Polymer chemistry》1987,25(6):1671-1679
The reaction in different molar ratios of trimethylchlorosilane to silicic acid offered partially silylated silicic acids PSSX (X = OH) with various degrees of silylation. Esterification and acetylation of PSSX (X = OH) with 1-butanol or acetylchloride gave polysiloxanes PSSX (X = OBun and OCOCH3). Some of them showed an excellent spinnability and provided a fine fiber with a length of about 250 cm. A fiber drawing test from concentrated PSSX solutions of various solvents revealed that spinnability markedly depended on the DS, functional group X of PSSX, and solvent. Spinnability may also be correlated to solubility parameter of PSSX and solvent. 相似文献