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121.
We show analytically that application of an identity in conformal invariant field theories to multidimensional guided-wave optics predicts a generic family of modes with algebraic (power-law) tails in the evanescent field. 相似文献
122.
123.
Takao Yamazaki Masanori Nagata Katsuhide Matoba Hiroki Takahata Raymond N. Castle 《Journal of heterocyclic chemistry》1977,14(3):469-472
Homoveratrylamine (II) was condensed with 3-(2-carbomethoxyethyl)-1,3-dimethyl-2-pyrrol-idone (Ib) to furnish the corresponding amide (III), which was subjected to the Bischler-Napieralski reaction to afford the corresponding dihydroisoquinoline derivative (IV). Compound V was obtained by the reductive ring closure of Vila which was obtained by the hydrogena-tion of IV. The stereochemistry of V is proposed to have the anti-trans-trans quinolizidine conformation. 相似文献
124.
Yamada K Wada N Onaka H Matsubara R Isobe R Inagaki M Higuchi R 《Chemical & pharmaceutical bulletin》2005,53(7):788-791
An ante-iso type regio-isomer on the long chain base moiety of a glucocerebroside, HLC-2-A, has been isolated from its parent glucocerebroside molecular species HLC-2 composed of iso and ante-iso isomers, from the less polar lipid fraction of a chloroform/methanol extract of the sea cucumber Holothuria leucospilota. Reverse-phase HPLC that included a recycling system was effective in separating the regio-isomer from its counterpart, revealing a very close resemblance in structure. Other typical glucocerebroside molecular species HLC-1 and HLC-3 were obtained together with HLC-2. The structures of these glucocerebrosides were determined on the basis of chemical and spectroscopic evidence. 相似文献
125.
A significant temperature effect on the new photochemical reactions of 9-α-bromopropionylanthracene has been noted. In comparison to the temperature effect on the fluorescence intensity of 9-propionylanthracene, it was suggested that the rotation of the carbonyl group on photo-excitation might operate as an enhancing factor in the intersystem crossing process. 相似文献
126.
Volume perception, that is, perception of a partially enclosed space filled with a medium, can be assessed not only from binocular
viewing but also from motion. We studied the volume perception of a cylindrical object in motion. The motion (rotation, translation,
or rolling) of the cylindrical object was simulated with and without appearing and disappearing parts (ADPs). We found that
volume perception could be assessed easily with ADPs but was difficult without ADPs. These experimental results indicate that
ADPs are an essential factor for volume perception from motion, which is correspond to binocularly unpaired regions for volume
perception in binocular viewing. 相似文献
127.
Scanning-tunneling spectroscopy at 5 K was used to investigate the electrostatic potential profile on the Si(111)-square root of 3 x square root of 3 Ag surface at subnanometer spatial resolution. The potential was measured from an energy-level shift of electronic states on the surface. The potential images obtained reveal that the potential drops around the steps and Ag adsorbates, upon which positive charges are presumably accumulated. The profiles of the reduced potentials are explained with the screening of potential due to the charges by two-dimensional electron gas (2DEG) existing on the surface. The Friedel oscillation, which results from the screening and has a period of the half Fermi wavelength of the 2DEG, was also observed in the potential images. 相似文献
128.
Masahito Katto Hironari Zushi Wataru Nagaya Shinya Harano Ryota Matsumoto Atushi Yokotani Masanori Kaku Shoichi Kubodera Noriaki Miyanaga 《Applied Physics A: Materials Science & Processing》2010,101(2):297-301
We have developed intense vacuum ultraviolet (VUV) radiation sources for advanced material processing, such as photochemical
surface reactions and precise processing on a nanometer scale. We have constructed a new VUV laser system to generate sub-picosecond
pulses at the wavelength of 126 nm. A seed VUV pulse was generated in Xe as the 7th harmonic of a 882-nm Ti:sapphire laser.
The optimum conversion was achieved at the pressure of 1.2 Torr. The seed pulse will be amplified by the Ar2*\mathrm{Ar}_{2}^{*} media generated by an optical-field-induced ionization Ar plasma produced by the Ti:sapphire laser. We have obtained a gain
coefficient of g=0.16 cm−1. Our developing system will provide VUV ultra-short pulses with sub-μJ energy at a repetition rate of 1 kHz. 相似文献
129.
Zhaofei Li Jun Tang Masanori Watahiki 《Journal of Physics and Chemistry of Solids》2010,71(4):495-1635
We have successfully synthesized the α-FeSex binary tetragonal superconductors with nominal composition of FeSex (x=0.6-1.0) via conventional solid state reactions between Fe and Se sealed in quartz tubes. Fe and β-FeSe are the most commonly seen impurities in this binary system. A low-temperature annealing at 400 °C is found to be crucial to remove β-FeSe, which is the thermodynamic stable phase with hexagonal symmetry. For all the samples of FeSex, superconductivity is confirmed by magnetic measurements as well as resistivity measurements with their Tc at around 8 K. We noticed that their Tc does not vary with the different nominal Se amount. High-resolution synchrotron X-ray diffraction analysis revealed that the unit cell parameters of all these samples do not change within the error range, and their structure only tolerate the same very small amount of Se deficiency. Based on this study, we concluded that the α-FeSex superconductor only exist in a very narrow deficiency range. 相似文献
130.
Heteropolyacid-encapsulated self-assembled materials for anhydrous proton-conducting electrolytes 总被引:3,自引:0,他引:3
The composite material of heteropolyacid (12-phosphotungstic acid; PWA) and polystyrene sulfonic acid (PSS) construct the PWA-encapsulated material by the self-assembly of -SO3H onto the PWA surface; as a result, the fast proton transfer occurred at the interface between the PWA and -SO3H, and the encapsulated material indicated the high anhydrous proton conductivity of 1 x 10(-2) S cm(-1) at 180 degrees C. These anhydrous proton-conducting materials without the existence of water molecules are quite different from customary ion-exchange membrane, such as Nafion, and may have advantages as an electrolyte membrane for polymer electrolyte membrane fuel cells operating at intermediate temperatures under anhydrous conditions but also for electrochemical devices including electrochromic displays, chemical sensors, and others. 相似文献