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101.
Th. Gray H. Löffler E. R. Weawer M. Shepherd E. B. King T. Shirai L. Heis H. Rodebush C. C. Coons M. L. Hamlin und T. H. Laby 《Fresenius' Journal of Analytical Chemistry》1929,76(3-4):150-152
Ohne Zusammenfassung 相似文献
102.
Yoko Tatewaki Dr. Tatsuya Hatanaka Ryo Tsunashima Dr. Takayoshi Nakamura Prof. Mutsumi Kimura Prof. Hirofusa Shirai Prof. 《化学:亚洲杂志》2009,4(9):1474-1479
Tetrathiafulvalenes (TTF) S‐TTF and R‐TTF having four chiral amide end groups self‐organize into helical nanofibers in the presence of 2,3,5,6‐tetrafluoro‐7,7′,8,8′‐tetracyano‐p‐quinodimethane (F4TCNQ). The intermolecular hydrogen bonding among chiral amide end groups and the formation of charge‐transfer complexes results in a long one‐dimensional supramolecular stacking, and the chirality of the end groups affects the molecular orientation of TTF cores within the stacks. Electronic conductivity of a single helical nanoscopic fiber made of S‐TTF and F4TCNQ is determined to be (7.0±3.0)×10?4 S cm?1 by point‐contact current‐imaging (PCI) AFM measurement. Nonwoven fabric composed of helical nanofibers shows a semiconducting temperature dependence with an activation energy of 0.18 eV. 相似文献
103.
The optimum composition of a chitin-based biocomposite was determined based on both its fluoride adsorption capacity and its chemical resistance in acid aqueous solution. Parameters such as the chitin content, additive content, catalyst content, chitin particle size, degree of acetylation of chitin and effect of pH on adsorption were evaluated. It was possible to chemically reinforce chitin while keeping an acceptable fluoride adsorption capacity onto the chitin-based biocomposites. Optimum chitin content (60%) was limited by the polymer-biopolymer anchoring capacity. An amine-based additive was used to improve the biocomposite adsorption capacity; however, its inclusion was not suitable in terms of biocomposite chemical resistance. The chitin particle size had no effect on adsorption capacity, and the degree of acetylation of chitin notably modified biocomposite adsorption capacity. On the other hand, the biocomposite chemical resistance was notably improved compared to pure chitin. The physicochemical properties of the optimum chitin-based biocomposite showed its potential for being used in continuous adsorption processes. 相似文献
104.
105.
Shigenori Kamada Hirotaka Nomoto Katsutoshi Fukuda Tadashi Fukawa Hirofusa Shirai Mutsumi Kimura 《Colloid and polymer science》2011,289(8):925-932
A facile and scalable preparation of dispersion of isolated graphene in various organic solvents has been developed by combining
between covalent and noncovalent functionalizations of the graphene surface. Covalently functionalized graphene (FRG) was
prepared by the reaction of partially reduced graphene oxide with aryl diazonium salts, followed by the graphene oxide being
completely reduced with hydrazine. The resulting FRG disperse readily in organic solvents such as N,N′-dimethylformamide (DMF) and N-methyl-2-pyrrolidinone and the functionalization of graphene was characterized by Fourier transform infrared spectroscopy,
thermogravimetric thermogram, X-ray photoelectron spectroscopy, and Raman spectroscopy. The hydrophobic surface of FRG was
noncovalently wrapped with aromatic hexakis-dodecylhexa-peri-benzocorone (HBC) by simply mixing of dispersion of FRG in DMF with toluene solution of HBC. The complexation of FRG and
HBC was monitored by viewing the absorption and fluorescence spectral changes. Atomic force microscopic images confirmed that
graphene was covalently and noncovalently functionalized, while keeping a two-dimensional sheet shape. 相似文献
106.
Asuka Nishikawa Shintaro Saito Yuichi Hashimoto Kenji Koga Ryuichi Shirai 《Tetrahedron letters》2001,42(52)
Efficient synthesis of l-α-phosphatidyl-d-myo-inositol 3,5-bisphosphate was achieved from 1,2,5,6-diisopropylidene-d-glucose by utilizing ring-closing metathesis and catalytic OsO4 dihydroxylation. 相似文献
107.
Takamasa Suzuki Yasuhito Ban-nai Masato Shirai Osami Sasaki 《Optics Communications》2010,283(1):104-108
We exploited the wavelength tunability of the laser diode of a phase-shifting Sagnac interferometer to realize disturbance-free measurements. The Sagnac interferometer is robust against mechanical disturbances because it has a common path configuration and requires no special references. An unbalanced optical path was introduced between p- and s-polarized beams to enable easy phase shifting by direct current modulation. The experimental results indicate that the proposed system is effective for performing precise disturbance-free measurements. 相似文献
108.
Hisamatsu Y Hasada K Amano F Tsubota Y Wasada-Tsutsui Y Shirai N Ikeda S Odashima K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(29):7733-7741
A new structure for an adenine-selective host molecule, featuring the pertinent link of five-six-five-membered heteroaromatic rings and two carbamoyl NH sites, was developed. This structure provides a correctly oriented array of complementary hydrogen bonding sites for the adenine nucleobase, which exploits both Watson-Crick and Hoogsteen-type interactions. The complexation with adenine nucleobases by multiple hydrogen bonding was supported by (1)H NMR spectroscopy. This type of host displayed high selectivity in complexation, with an accompanying fluorescent response to lipophilized adenosine in CHCl(3). Furthermore, a remarkably selective potentiometric response was attained for adenosine 5'-monophosphate over 5'-GMP, 5'-CMP, and 5'-UMP by using an ion-selective electrode with a PVC-supported solvent polymeric membrane. This indicates recognition of water-soluble nucleotide guests through the membrane-water interface. These findings are expected to form a reliable basis for the development of artificial sensing systems for mononucleotides in biological systems. 相似文献
109.
Reaction of lithium alpha-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides with ketones or aldehydes at low temperature gave adducts in almost quantitative yields. Treatment of the adducts derived from ketones with trifluoroacetic anhydride (TFAA) in the presence of NaI in acetone gave alpha-sulfanyl allylic alcohols in good to quantitative yields. On the other hand, treatment of the adducts derived from aldehydes with TFAA and NaI resulted in the formation of alpha-sulfanyl ketones and/or alpha-sulfanyl allylic alcohols. These reactions offer a good method for the synthesis of the above-mentioned compounds from ketones and aldehydes with carbon-carbon bond-formation in two steps and in good yields. 相似文献
110.
Tomoyuki Shirai 《Journal of statistical physics》2006,123(3):615-629
For the fermion point process on the whole complex plane associated with the exponential kernel , we show the central limit theorem for the random variable ξ(D
r
, the number of points inside the ball D
r
of radius r, as r → ∞ and we establish the large deviation principle for the random variables {r
−2ξ (D
r
), r > 0}. 相似文献