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41.
Takenori Tomohiro Kouichi Uoto Takehiko Shimura Hiroaki Okuno 《Journal of heterocyclic chemistry》1988,25(5):1463-1465
Tetra-aza macrocycles with 28- to 44-membered rings can be readily synthesized by reaction of dibromide and ditosyldiamide without use of a high dilution method. The reaction proceeded very smoothly with a 10 mM concentration in DMF, and gave the macrocycles in excellent yields (60–80%). Favorable effects of cesium ion on the cyclization have been observed. 相似文献
42.
Jun-ichi Nishizawa Takenori Tanno Ken Suto 《Journal of organometallic chemistry》2006,691(11):2479-2482
The terahertz transmission spectra of crystalline metallocenes and decamethyl metallocene were clearly measured in the range of 0.7-6.2 THz by a recently developed GaP Raman terahertz spectrometer. The low-frequency mode of ring-metal-ring bending and CH3 out-of-plane oscillation were observed, and the force constants of bending were estimated from the absorption frequencies based on a three-body model. 相似文献
43.
Tatsuomi Matsuoka Takenori Tsuda Masaki Ishida † Yoji Kato Miyuki Takayanagi Takeshi Fujino Shun Mizuta 《Photochemistry and photobiology》1994,60(6):598-604
Abstract-The red pigment granule of Belpharisma japonicum is believed to be a photoreceptor organelle mediating photodispersal. Freeze-fracture and thin section electron microscopy revealed that the pigment granules contained a honeycomb-like structure constructed of folded membranes. In the fracture face of the honeycomb-like structure, small membrane particles were observed, which might correspond to pigment—protein complexes. The pigment granules were isolated and detergent-solubilized. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the pigment granules mainly contained a 200 kDa membrane protein. The complex of red pigment and 200 kDa protein was isolated by gel-filtration chromatography of the detergent-solubilized components, and the protein was subjected to SDS-PAGE and amino acid analysis. The 200 kDa protein could not be dissociated into subunits by 2-mercaptoethanol, indicating that the protein is composed of a single polypeptide chain. Hydrophobic amino acids contained in the 200 kDa protein were not dominant, suggesting that only partial domains may extend across the membrane of the honeycomb-like structure. 相似文献
44.
Tatsuo Ishikawa Kumi Matsumoto Takenori Nakayama 《Journal of solid state chemistry》2006,179(4):1110-1118
Zinc hydroxide chloride particles were synthesized by hydrolysis of ZnCl2 solutions dissolving AlCl3 at different atomic Al/Zn ratios from 0 to 1.0 and characterized by various techniques. Increasing Al/Zn ratio changed the crystal phases of the products as ZnO→ZnO+ZHC (Zn5(OH)8Cl2·H2O)→ZHC→LDH (layered double hydroxides, Zn-Al-Cl) and the particle morphology as agglomerates (ZnO)→fine particles (ZnO)→plates (ZHC)+rods (ZnO)→plates (ZHC)→plates (LDH). The atomic Cl/Zn ratios of LDH particles formed at Al/Zn?0.3 were ca. 0.3 despite the increase of Al/Zn ratio, being due to the intercalation of CO32− into the LDH crystal. The OH− content of LDH estimated by TG was reduced by the deprotonation of OH− to counteract the excess positive charge produced by replacing Zn(II) with Al(III). ZHC exhibited a high adsorption selectivity of H2O. 相似文献
45.
Taniguchi M Uchio Y Yasumoto K Kusumi T Ooi T 《Chemical & pharmaceutical bulletin》2008,56(3):378-382
New brominated fatty acids (3, 5-8, 10) and new sterol esters (14-16) have been isolated from an unidentified marine sponge collected in Papua New Guinea. Their structures were determined on the basis of their spectroscopic data. A major component of the marine sponge (1) was tested for activities against Arutemia salina and some fungi. 相似文献
46.
Yasumoto K Nishigami A Aoi H Tsuchihashi C Kasai F Kusumi T Ooi T 《Chemical & pharmaceutical bulletin》2008,56(1):133-136
New aliphatic sulfates and sulfamates were isolated from Daphnia pulex as the Daphnia kairomones that induced morphological defense of a freshwater phytoplankton Scenedesmus gutwinskii var. heterospina (NIES-802). Their structures were determined by spectroscopic and synthetic studies. 相似文献
47.
He C Shantarovich VP Suzuki T Stepanov SV Suzuki R Matsuo M 《The Journal of chemical physics》2005,122(21):214907
An enhanced positronium (Ps) formation in low-temperature polymers has been widely observed. The additional positronium formation is due to shallow trapped electrons in them. Positron annihilation lifetime spectroscopy was applied to investigate the Ps formation in a series of polymers, such as low-density polyethylene, ethylene-methyl methacrylate copolymers with various methyl methacrylate contents, and pure poly(methyl methacrylate) at low temperature. An analysis of the experimental data based on simple kinetic equations enables one to understand the Ps formation mechanism in polymers during low-temperature positron annihilation experiments as functions of the temperature and elapsed time. Good fittings of the experimental data were obtained. The fitting parameters seemed to show clear physical meanings. 相似文献
48.
Negoro Masaaki Shioji Norio Ikuta Yoshiaki Makita Takenori Uchiumi Makoto 《Applied biochemistry and biotechnology》1992,(1):681-692
In order to reduce release of CO2 contained in the flue gas from a power plant, we assumed a system in which the flue gas was directly blown into a pond and
CO2 was fixed on microalgae. We have experimentally examined the basic growth characteristics, such as trace components of culture
medium, effects of impurities from exhaust gas, and light utilization rate of algal productivity, mainly forNonnochloropsis sp. NANNP-2 from SERI collection. Although Ni and V contained in heavy oil burnt ashes dissolve into culture solution, their
concentrations are low, and they have no particular adverse effect on growth as impurities.
Culture medium trace component (i.e., heavy metals and vitamins) are essential for the NANNP-2. However, for the PHAEO-2(Phaeodactylum sp.), the growth rate hardly changes, even if vitamins and heavy metals other than Fe are eliminated. 相似文献
49.
Muhammad Aswad Junya Chiba Yasumaru Hatanaka Takenori Tomohiro 《Tetrahedron letters》2019,60(24):1611-1613
The synthesis of sulfonylguanidines from N,N,N',N'-tetramethylthiourea and sulfonyl azides is described. This method serves as an alternative route for generating sulfonylguanidines via the use of stable starting materials. 相似文献
50.
We present a theoretical study on electron and hole trap states in the bulk and (001) surface of anatase titanium dioxide using screened hybrid density functional calculations. In both the bulk and surface, calculations suggest that the neutral and ionized oxygen vacancies are possible electron traps. The doubly ionized oxygen vacancy is the most stable in the bulk, and is a candidate for a shallow donor in colorless anatase crystals. The hole trap states are localized at oxygen anions in both the bulk and surface. The self-trapped electron centered at a titanium cation cannot be produced in the bulk, but can be formed at the surface. The electron trap level at the surface oxygen vacancy is consistent with observations by photoelectron spectroscopy. The optical absorptions and luminescence in UV-irradiated anatase nanoparticles are found to come from the surface self-trapped hole and the surface oxygen vacancy. 相似文献