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391.
Yuzu is a typical Japanese citrus with a desirable smell. The objectives of this study are to establish a process for pressure-induced marmalade (without both heating or the addition of pectin) and compare it with heat-induced marmalade. Sliced peel (flavedo) was soaked in 2% citric acid solution (pH 2.0). Albedo, endocarp and juice sacs were homogenized with 0.3% citric acid solution (pH 2.5). After soaking for 24 h, these were mixed and 50% or 60% sucrose of the total weight was added, then pressurized at 500 MPa or boiled (process A). Process B: all processing was done at pH 2.7. Peel of high pressure-induced marmalade maintained a natural color. Flavedo in heat-induced marmalade was softer than that of pressure-induced marmalade. There was no difference in viscosity between heat-induced and high pressure-induced marmalade. High pressure-induced marmalade with 50% sugar was preferred by a sensory test because fresh flavor and color were maintained. 相似文献
392.
393.
Yukio Imanishi Naoki Kawazoe Kensuke Ichizawa 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3632-3639
In expectation of the formation of a thermally stable, dielectric supramolecular assembly of a polypeptide with an amino acid sequence similar to that of type-2 collagen, a sequential polypeptide consisting of the repetition of the Pro-Pro-Gly tripeptide was synthesized by solid-phase synthesis. Column chromatography of an ethanol solution of (Pro-Pro-Gly)10 NH2 showed the presence of a double helix or triple helix of the polypeptide. The pattern of a circular dichroism (CD) spectrum of an ethanol solution of (Pro-Pro-Gly)10 NH2 was very similar to that of an aqueous solution of (Pro-Pro-Gly)10 OH, strongly suggesting the presence of a triple helix of the polypeptide in ethanol. An oriented monolayer assembly of (Pro-Pro-Gly)10 NH2 was formed on a thin gold film. The distribution of surface unevenness and the surface potential were investigated with Kelvin force microscopy. The rising spots carried an electric potential from room temperature to 150 °C. The correspondence showed the usefulness of the oriented monolayer of the sequential polypeptide materials for thermally stable, dielectric nanodevices. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3632–3639, 2003 相似文献
394.
A. Kumar Singh V. Kumar Y. Kawazoe 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,34(1-3):295-298
Using ab initio total energy calculations we demonstrate that the nanotubes of germanium with atomic structure based on an alternate prism and antiprism stacking of hexagonal rings, can be stabilized by metal encapsulation. The V or Nb doped infinite nanotube is metallic. However, Mo doping leads to the formation of a metal encapsulated direct band gap semiconducting nanotube of germanium. These nanotubes with metal dependent electronic properties could prove to be vital for the development of future nanotechnologies. 相似文献
395.
Michiko Yuri 《Transactions of the American Mathematical Society》2003,355(7):2949-2971
For countable to one transitive Markov systems we establish thermodynamic formalism for non-Hölder potentials in nonhyperbolic situations. We present a new method for the construction of conformal measures that satisfy the weak Gibbs property for potentials of weak bounded variation and show the existence of equilibrium states equivalent to the weak Gibbs measures. We see that certain periodic orbits cause a phase transition, non-Gibbsianness and force the decay of correlations to be slow. We apply our results to higher-dimensional maps with indifferent periodic points.
396.
397.
A. Kasuya Y. Noda I. Dmitruk V. Romanyuk Y. Barnakov K. Tohji V. Kumar R. Belosludov Y. Kawazoe N. Ohuchi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,34(1-3):39-41
Nanoparticles of (CdSe)n are found extremely stable at n = 33
and 34 with structures distinctively different from the bulk fragments. They
grow exclusively in large amount with a simple solution method. The diameter
is determined as 1.5 nm. Such ultra-stable nanoparticles had been predicted
both theoretically and experimentally after the discovery of carbon
fullerenes, but not been produced macroscopically in any other element or
compound system. First-principles calculations predict that the structures of (CdSe)33
and (CdSe)34 are puckered (CdSe)28-cages accommodating
respectively (CdSe)5 an (CdSe)6 inside to form a three-dimensional
network of essentially hetero-polar sp3-bonding. 相似文献
398.
Hypervalent radical formation probed by electron transfer dissociation of zwitterionic tryptophan and tryptophan‐containing dipeptides complexed with Ca2+ and 18‐crown‐6 in the gas phase
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Akimasa Fujihara Sou Matsuo Michiko Tajiri Yoshinao Wada Shigeo Hayakawa 《Journal of mass spectrometry : JMS》2015,50(10):1124-1129
The relationship between peptide structure and electron transfer dissociation (ETD) is important for structural analysis by mass spectrometry. In the present study, the formation, structure and reactivity of the reaction intermediate in the ETD process were examined using a quadrupole ion trap mass spectrometer equipped with an electrospray ionization source. ETD product ions of zwitterionic tryptophan (Trp) and Trp‐containing dipeptides (Trp‐Gly and Gly‐Trp) were detected without reionization using non‐covalent analyte complexes with Ca2+ and 18‐crown‐6 (18C6). In the collision‐induced dissociation, NH3 loss was the main dissociation pathway, and loss related to the dissociation of the carboxyl group was not observed. This indicated that Trp and its dipeptides on Ca2+(18C6) adopted a zwitterionic structure with an NH3+ group and bonded to Ca2+(18C6) through the COO? group. Hydrogen atom loss observed in the ETD spectra indicated that intermolecular electron transfer from a molecular anion to the NH3+ group formed a hypervalent ammonium radical, R‐NH3, as a reaction intermediate, which was unstable and dissociated rapidly through N–H bond cleavage. In addition, N–Cα bond cleavage forming the z1 ion was observed in the ETD spectra of Trp‐GlyCa2+(18C6) and Gly‐TrpCa2+(18C6). This dissociation was induced by transfer of a hydrogen atom in the cluster formed via an N–H bond cleavage of the hypervalent ammonium radical and was in competition with the hydrogen atom loss. The results showed that a hypervalent radical intermediate, forming a delocalized hydrogen atom, contributes to the backbone cleavages of peptides in ETD. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
399.
Yoshihiro Suyama Yusuke Higashino Naonobu Tanaka Yutaka Tatano Hideki Yagi Kazuyoshi Kawazoe Kotaro Murakami Shun-Lin Li Han-Dong Sun Yoshiki Kashiwada 《Tetrahedron letters》2017,58(48):4568-4571
Three new naphthoquinone derivatives, rubiaquinones A–C (1–3), were isolated from the roots of Rubia yunnanensis. Rubiaquinone A (1) was a racemic naphthoquinone dimer consisting of a 1,4-dihydroxynaphthalene and a 4-hydroxy-1,2-naphthoquinone moieties with a 2-oxo-propyl group. Rubiaquinones B (2) and C (3) were structurally unique trimeric naphthoquinones with a racemic nature possessing one chiral axis and one chiral carbon in common. The planar structures of 1–3 were assigned by detailed spectroscopic analyses, and enantiomers of 1–3 were obtained by optical resolutions. The absolute configurations of (+)-1 and (?)-1 were elucidated by interpretation of the ECD spectra with the aid of TDDFT ECD calculation, while those of enantiomers obtained from 2 and 3 were assigned by analyses of the composite ECD spectra generated by summing appropriate ECD spectra of enantiomers. Rubiaquinone A (1) exhibited antimicrobial activity against Bacillus subtilis. 相似文献
400.
W. Nomura T. Yatsui T. Kawazoe M. Naruse M. Ohtsu 《Applied physics. B, Lasers and optics》2010,100(1):181-187
The distribution dependency of quantum dots was theoretically and experimentally investigated with respect to the basic properties
optical excitation transfer via optical near-field interactions between quantum dots. The effects of three-dimensional structure
and arraying precision of quantum dots on the signal transfer performance were analyzed. In addition, the quantum dot distribution
dependency of the signal transfer performance was experimentally evaluated by using stacked CdSe quantum dots and an optical
near-field fiber probe tip laminated with quantum dots serving as an output terminal, showing good agreement with theory.
These results demonstrate the basic properties of signal transfer via optical near-field interactions and serve as guidelines
for a nanostructure design optimized to attain the desired signal transfer performances. 相似文献