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901.
Combination of magnetically-resonant dielectric resonators and TE cut-off waveguide structures provides unbalanced or balanced
composite right/left handed transmission lines. This idea has been expanded into 1-D, 2-D, and 3-D composite structures, and
can be applied to potential microwave and millimeter wave circuits and antennas in the same manner as conventional composite
right/left handed transmission lines. 相似文献
902.
Ueda M Makino A Imai T Sugiyama J Kimura S 《Langmuir : the ACS journal of surfaces and colloids》2011,27(8):4300-4304
Vesicles prepared from a mixture of (Sar)(25)-b-(L-Leu-Aib)(6) (SLL) and (Sar)(25)-b-(D-Leu-Aib)(6) (SDL) fused with themselves upon heating to 90 °C. The vesicles also fused with (Sar)(28)-b-(L-Leu-Aib)(8) vesicles upon heating to 90 °C. The temperature-triggered fusion was due to the phase transition of the mixed membrane of SLL and SDL at 90 °C and should be driven by the bending energy stored in the stereocomplex membrane upon taking a vesicular structure. 相似文献
903.
New appropriate reaction system was found for spectrophotometric determination of phosphate anion. This spectrophotometric method is based on the color development due to the formation of yellow molybdophosphate anion in acidic ethylene glycol-water (EG-W) mixed solution containing Mo(VI) species. The solution containing e.g. 20 mM Na(2)MoO(4), 0.1 M HCl, and 40% (v/v) EG is colorless, and becomes immediately yellow by addition of phosphate anion. Thus the method is simple, rapid, and easy to carry out. Although Si(IV) species is well known to interfere with the determination of phosphate anion in many cases, the EG-W Mo(VI) solution remains colorless after addition of silicate anion at 1 mM level, indicating that no yellow molybdosilicate anion was formed in the EG-W solution. Under an optimized condition, the absorbance at e.g. 400 nm of the EG-W P(V)-Mo(VI) solution was proportional to the concentration of phosphate anion with good reproducibility, and the detection limit was 1 μM. Also the present method is less interfered by high concentrations of potassium and ammonium cations and oxidative nitrite anion as well as silicate anion. 相似文献
904.
Hiroshi Hasegawa Toshihisa Ueda Takeshi Yokomori 《Proceedings of the Combustion Institute》2013,34(2):2155-2162
This paper reports the synthesis of core shell phosphor particles (Y2Si2O7:Eu/SiO2) produced by flame spray pyrolysis with yttrium and europium nitrates and colloidal silica dispersed precursor solutions. Particles of various structures were produced, including heterogeneous, core shell and non-spherical core shell particles, depending on the synthesis conditions; the ideal core shell structure was obtained under the highest flame temperature and high silicon concentration in the precursor solution. Based on the phase diagram, the formation of the core shell structure was caused by the separation of each component at the liquid phase in the synthesis route. In the energy-dispersive X-ray spectroscopy, yttrium could be detected only at the core part of the particle, while silicon and oxygen could be detected at both the shell and core parts. Under ultraviolet excitation, the ideal core shell particles of Y2Si2O7:Eu showed photoluminescent characteristics. Consequently, it could be concluded that Y2Si2O7:Eu/SiO2 core shell phosphor particles were successfully synthesized by flame spray pyrolysis. 相似文献
905.
Abstract The vanadium bronzes.β-A0.33V2O5(A= Ca and Sr) have been synthesized, and their electromagnetic properties investigated. They show phase transitions at 150K and 170K, respectively, accompanying with anomalies in the magnetic susceptibility and resistivity curves. These transitions are of charge order type. Below the transition temperature the magnetic susceptibility showed low dimensional behavior in both compounds, especially spin gap behavior in Sr0.33V2O5. Such behavior is closely related to the crystal structure characteristic of the vanadium β-bronzes and a manner of ordering for magnetic V4+ ions at the transition. 相似文献
906.
Theory of spin fluctuations for itinerant magnetism and its application to high temperature superconductivity are reviewed. After a brief introduction to the whole subject the developments of the self-consistent renormalization theory of spin fluctuations are summarized with particular emphasis on critical properties at the quantum phase transitions. Most of the anomalous properties in the normal state of high-Tc cuprates are understood as due to the critical behaviours for the two dimensional antiferromagnetic metals. By analysing the nuclear magnetic relaxation rate and the T-linear term of resistivity, the set of parameters to specify the spin fluctuations are determined. It is shown that by using the parameters thus obtained one can describe other quantities as well, e.g. optical conductivity. Then we proceed to the theory of superconductivity by the spin fluctuation mechanism. After some discussion on the weak coupling treatments, the strong coupling theory is reviewed. It is shown that the set of parameters determined by the normal state properties of the high-T c cuprates just give a transition temperature of the right order of magnitude. Among the parameters, the most sensitive one for T c is the frequency spread of the spin fluctuations. This fact enables us to present a possible unified picture of the antiferromagnetic spin fluctuation-induced superconductors, including heavy fermion superconductors and organic superconductors. This point of view may be confirmed to a certain extent by microscopic calculations based on the fluctuation exchange approximation for the two-dimensional Hubbard models representing not only the cuprates but also organic and trellis lattice compounds. The review is concluded with some discussions on future problems, e.g. the pseudo spin-gap in the under-doped region. 相似文献
907.
908.
Chikako Nishigori Eiji Nakano Taro Masaki Ryusuke Ono Seiji Takeuchi Mariko Tsujimoto Takehiro Ueda 《Photochemistry and photobiology》2019,95(1):140-153
Xeroderma pigmentosum (XP) is a rare autosomal recessive hereditary disease caused by deficiency in repair of DNA lesions generated by ultraviolet radiation and other compounds. Patients with XP display pigmentary change and numerous skin cancers in sun‐exposed sites, and some patients show exaggerated severe sunburns even upon minimum sun exposure as well as neurological symptoms. We conducted a nationwide survey for XP since 1980. In Japan, the frequency of the XP complementation group A is the highest, followed by the variant type; while in the Western countries, those of groups C or D are the highest. Regarding skin cancers in XP, basal cell carcinoma was the most frequent cancer that afflicted patients with XP, followed by squamous cell carcinoma, and malignant melanoma. The frequency of these skin cancers in patients with XP has decreased in these 20 years, and the age of onset of developing skin cancers is higher than those previously observed, owing to early diagnosis and education to patients and care takers on strict prevention from sunlight for patients with XP. On the other hand, the effective therapy for neurological XP has not been established yet, and this needs to be done urgently. 相似文献
909.
Misaki Ueda Zi Lang Goo Katsue Minami Nobuto Yoshinari Takumi Konno 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(41):14815-14820
A 60‐nuclear silver sulfide nanocluster with a highly positive charge ( 1 ) has been synthesized by mixing an octahedral RhIII complex with 2‐aminoethanethiolate ligands, silver(I) nitrate, and d ‐penicillamine in water under mild conditions. The spherical surface of 1 is protected by the chiral octahedral RhIII complex, with cleavage of the C?S bond of the d ‐penicillamine supplying the sulfide ions. Although 1 does not contain d ‐penicillamine, it is optically active because of the enantiomeric excess of the RhIII molecules induced by chiral transfer from d ‐penicillamine. 1 can accommodate/release external Ag+ ions and replace inner Ag+ ions by Cu+ ions. The study demonstrates that a thiolato metal complex and sulfur‐containing amino acid can be used as cluster‐surface‐protecting and sulfide‐supplying regents, respectively, for creating chiral, water‐soluble, structurally precise silver sulfide nanoclusters, the properties of which are tunable through the addition/removal/exchange of Ag+ ions. 相似文献
910.
So Fujinami Eijun Ueda Ken Nakajima Toshio Nishi 《Journal of Polymer Science.Polymer Physics》2019,57(18):1279-1286
We present new DMT‐based and JKR‐based methods to derive the elastic modulus of sample surfaces from an atomic force microscope force‐distance curve (DMT: Derjaguin‐Muller‐Toporov, JKR: Johnson–Kendall–Roberts). Application of the methods to the Maugis–Dugdale curves revealed that the JKR‐based method determines very accurate moduli for Maugis' transitional parameter λ > 0.3; however, the DMT‐based method generally estimates much less accurate moduli. The new JKR‐based method has advantages over the two‐point method, which has been often used for the JKR analysis, in capabilities to select the fitting range and to involve more than two points in curve fitting. Utilizing the advantages, for example, one can limit the fitting range to the attractive force zone to reduce the contact area of soft and adhesive materials. The method consists of algebraical calculation and optionally linear fitting; hence, the computational cost is low enough to be applicable to a real‐time JKR analysis method of fast force mapping. The detailed procedure of the method is explained using a force‐distance curve on a poly(dimethylsiloxane) surface. The advantages of the method are demonstrated using a force mapping data on a vulcanized rubber blend. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1279–1286 相似文献