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91.
The Landau-Lifshitz fluctuating fluxes in fluctuating hydrodynamics are derived from the deterministic Boltzmann equation with the aid of a reduction method developed by Fujisaka and Mori. Thus it is shown that the hydrodynamic fluctuations innonequilibrium systems are generated by the reduction of variables from the-space distribution function to its five momentum moments, i.e., the hydrodynamic variables. This differs from the Bixon-Zwanzig and Fox-Uhlenbeck theories, in which the Landau-Lifshitz fluctuating fluxes are derived from the molecular fluctuating force in thestochastic Boltzmann-Langevin equation, which is, however, negligible in nonequilibrium systems. Thus the present method improves the Chapman-Enskog reduction method so as to include the hydrodynamic fluctuations generated by the reduction of variables.Supported in part by the Scientific Research Fund of the Ministry of Education. 相似文献
92.
(1R, 6S, 7S, 11R)-(+)-Biflora-4, 10(19),15-triene was synthesized starting from (r)-(+)-citronellic acid. This enabled us to assign (1S), 6R, 7R, (11S)-stereochemistry to the naturally occurring (-)-enantiomer isolated from soldiers of the termite species Cubitermes umbratus. 相似文献
93.
Jun Suzuki Kenjiro Fujimoto Toshiyuki Mori Mamoru Watanabe Yoshio Hasegawa 《Journal of Sol-Gel Science and Technology》2000,19(1-3):775-778
The photocatalytic reduction of nitrogen monoxide (NO) with ethane on the hollandite type catalyst (K2Ga2Sn6O16KGSO) was investigated. Using a closed-gas circulating system equipped with a Q-MASS detector and in-situ diffuse reflectance FT-IR spectroscopy. The reactant gases of NO and 13C2H6 decreased with the increasing irradiation time. In contrast, the N2 yield increased proportionally to the conversion of 13C2H6. Nitrogen oxides such as N2O did not reach their detectable levels. The NO adsorbed on KGSO was found to change to its activated species by UV irradiation. The oxidized products of C2H6 such as CH3CHO increased in proportion to the reaction time. The present results strongly suggest that KGSO has remarkable photocatalytic activity for the reduction of NO with C2H6. 相似文献
94.
Tsukasa Matsunaga YURI HATAKEYAMA Michi Ohta Toshio Mori Osamu Nikaido 《Photochemistry and photobiology》1993,57(S1):934-940
Abstract— We established a monoclonal antibody(DEM–1) that recognizes UV-induced DNA damage other than cyclobutane pyrimidine dimers or(6–4)photoproducts. The binding ofDEM–1 antibody to 254 nm UV-irradiated DNA increased with subsequent exposure to UV wavelengths longer than 310 nm, whereas that of the 64M-2 antibody specific for the(6–4)photoproduct decreased with this treatment. Furthermore, the increase inDEM–1 binding was inhibited by the presence of the 64M-2 antibody during the exposure. We concluded that theDEM–1 antibody specifically recognized the Dewar photoproduct, which is the isomeric form of the(6–4)photoproduct. TheDEM–1 antibody, however, also bound to DNA irradiated with high fluences of 254 nm UV, suggesting that 254 nm UV could induce Dewar photoproducts without subsequent exposure to longer wavelengths of UV. Furthermore, an action spectral study demonstrated that 254 nm was the most efficient wavelength for Dewar photoproduct induction in the region from 254 to 365 nm, as well as cyclobutane dimers and(6–4)photoproducts, although the action spectrum values in the U V-B region were significantly higher compared with those for cyclobutane dimer and(6–4)photoproduct induction. 相似文献
95.
Spectrophotometric determinations of palladium(II) and tartaric acid were respectively investigated by using the color reactions between 2(5-nitro-2-pyridylazo)-5-(N-propyl-N-3-sulfopropylamino)phenol(5-NO2.PAPS) and palladium(II) in strong acidic media, and between 5-NO2.PAPS, niobium(V) tartaric acid in weak acidic media. The calibration graphs were linear in the range of 0–25 μg/10 ml palladium(II), with an apparent molecular coefficient () of 6.2×104 l mol−1 cm−1 at 612 nm, and 0–23 μg/10 ml tartaric acid with =1.08×106 l mol−1 cm−1 at 612 nm, respectively. The proposed methods were selective and sensitive in comparison with other chelating pyridylazo dyes–palladium(II) or metavanadic acid–tartaric acid method, and the effect of foreign ions such as copper(II) was negligible for the assay of palladium(II) with 5-NO2.PAPS. 相似文献
96.
Tetsuro Kato Ryosuke Nemoto Hisashi Mori Ryoetsu Abe Katsuo Unno Akio Goto Hideyuki Murota Masaoki Harada Motofumi Homma 《Applied biochemistry and biotechnology》1984,10(1-3):199-211
To achieve targeted distribution of anticancer drugs with sustained activity, ferromagnetic ethylcellulose microcapsules containing
an anticancer drug, mitomycin C (FM-MMC-mc), were prepared by a method based on phase separation principles. Two prototypes
of FM-MMC-mc were made: one with the drug as the core and zinc ferrite on its capsular surface (outer type); the other with
both the drug and zinc ferrite as the core (inner type). Both preparations provided a sustained-release property and a sensitive
response to conventional magnetic force, although certain differences in the release rate of drug, magnetic responsiveness,
and particle size were found between the two dosage forms. Animal studies showed that the magnetic microcapsules could be
magnetically controlled in the artery and urinary bladder. VX2 tumors in the rabbit hind limb and urinary bladder were successfully
treated with magnetic control of FM-MMC-mc. Pharmacokinetic study revealed that the targeting of the microcapsules markedly
enhanced the drug absorption into the surrounding tissues for a prolonged period of time. The results indicate the feasibility
and effectiveness of the magnetic microcapsules as a targeted drug delivery system. 相似文献
97.
Ion chromatographic separation of hydrogen ion and other common mono- and divalent cations 总被引:1,自引:0,他引:1
We introduced an approach to the ion chromatographic determination of common mono- and divalent cations including hydrogen ion and demonstrated the ability of a C30 column dynamically coated first with dodecylsulfate and then with 18-crown-6 ether to separate the cations by ion-exchange mechanism. Using an ethylenediamine solution containing a small concentration of 18-crown-6 ether and lithium dodecylsulfate at pH 6.2 as eluent, the cations were eluted in the order Li < Na+ < NH4+ < H+ < K+ < Mg2+ < Ca2+ with symmetrical peaks. The conductivity vs. concentration plots were linear about three orders of magnitude, from millimolar to micromolar; and the detection limits were all < 0.6 microM. Rainwater was analyzed directly using this ion chromatographic system with satisfactory results. 相似文献
98.
H Koga N Mori H Yamada Y Nishimura K Tokuda K Kato T Imoto 《Chemical & pharmaceutical bulletin》1992,40(4):965-970
Employing soluble denatured protein substrates and their derivatives, the proteolytic activity of rat cathepsin H was investigated. The enzyme showed aminopeptidase activity which sequentially released amino acid from the N-terminal of the substrate. The aminopeptidase activity did not act on N alpha-acetylated peptides and showed moderate ionic-strength dependence when methionyl-methylcoumarylamide was employed as a substrate. These results indicate that the activity essentially requires an N-terminal free amino group of the substrate and recognizes it electrostatically to some extent. On the other hand, the enzyme was also indicated to exhibit endopeptidase activity by employing appropriate N alpha-acetylated peptide substrates. In contrast to the aminopeptidase activity, the endopeptidase activity showed rather strict specificity, preferring hydrophobic residues at P2 and P3 sites. Because of the broad specificity and high efficiency of the aminopeptidase activity, it was difficult to directly observe endopeptidase activity in the digestion of large peptide substrates with a free alpha-amino terminal. Thus, this is the first experimental evidence that indicates endopeptidase activity by assigning internal peptide bonds cleaved by this activity. From this data, we proposed a model of the binding site of this enzyme. 相似文献
99.
T. Tsuchiya T. Sei Y. Watanabe M. Mori T. Kineri 《Journal of Sol-Gel Science and Technology》1997,8(1-3):685-688
Gold-dispersed BaTiO3, PGO and PLT thin films, which will be used for third-order nonlinear optical devices, were prepared by sol-gel process with
spin-coating using HAuCl44H2O, Ba(CH3COO)2, Ti[O(CH2)3CH3]4, Pb(CH3COO)23H2O, Ge[O-n-C4H9]4, La(CH3COO)31.5 H2O as starting materials. The thin films were heat-treated in air at temperatures ranging from 400 to 800 for 1 h. The nonlinear
optical property of these thin films was measured by the degenerate four-wave mixing (DFWM) method using a frequency-doubled
Nd: YAG laser with 20 ps pulse duration. Third-order nonlinear susceptibility χ(3) of gold-dispersed BaTiO3, PGO and PLT thin films with 5 vol% of gold were 1.410−6 esu, 3.510−7 esu respectively. The large χ(3) may be ascribed to the high dielectric constant of the films. 相似文献
100.
Takayuki Otsu Bunichiro Yamada Shigeru Sugiyama Shigeki Mori 《Journal of polymer science. Part A, Polymer chemistry》1980,18(7):2197-2207
Radical polymerization and copolymerization of some o-alkylphenyl methacrylates were carried out and the effect of the ortho-substituents on the ability to homopolymerize, on the monomer reactivities, and on the ceiling temperatures of the monomers was studied. The effect of the substituent on tacticities and thermal stabilities of the polymers formed was also discussed. The ability to honiopolymerize and the monomer reactivity were considerably decreased by the introduction of the o-substituent. 2,6-Di-tert-butylphenyl methacrylate formed no methanol-insoluble polymer at 60°C. On the basis of the tacticity determined it was noted that the o-substituted phenyl methacrylates preferred syndiotactic addition in the propagation reaction less than did phenyl methacrylate or methyl methacrylate. The polymers formed from the o-substituted monomers were thermally less stable than poly(phenyl methacrylate), and, consistent with this finding, ceiling temperatures of the o-substituted phenyl methacrylates seemed to be lower than that of phenyl methacrylate. The effects observed were characteristic of the o-substituents conformationally close to the carbon-carbon double bond of the monomer or the carbon carrying the unpaired electron of the polymer radical. 相似文献