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991.
Yamaguchi A Nakano M Nochi K Yamashita T Morita K Teramae N 《Analytical and bioanalytical chemistry》2006,386(3):627-632
The adsorption and longitudinal diffusion behaviors of a series of hemicyanine dyes to phospholipid vesicle membranes were
studied by second-harmonic generation (SHG) and fluorescence spectroscopies. It was observed that the longitudinal diffusion
of cationic hemicyanine dyes takes place immediately after the initial adsorption of these dyes to the outer surface of the
vesicle membrane. In contrast, hardly any amount of a zwitterionic hemicyanine dye with a sulfonate group diffused across
the vesicle membrane within the measurement time (<2000 s). Based on the difference in the time-course responses of SHG and
fluorescence spectroscopies for all of the hemicyanine dyes tested, we propose that hydration of the sulfonate group is mainly
responsible for the low diffusivity of the zwitterionic hemicyanine dye. 相似文献
992.
[STRUCTURE: SEE TEXT] Nine-membered diallylic cyclic amines and amides have remarkably stable planar chirality. The transformation of enantiomerically enriched amides provides optically active nitrogen heterocycles containing stereogenic centers in a stereospecific fashion. 相似文献
993.
Masaki Hori 《Hyperfine Interactions》2010,196(1-3):243-251
The ASACUSA collaboration of CERN has carried out several laser spectroscopy experiments of antiprotonic helium atoms. By comparing the results with three-body QED calculations, the antiproton-to-electron mass ratio was determined as $M_{\overline{p}}/m_e=1836.152674(5)$ . We are now developing some laser systems and detectors to further improve the experimental precision. 相似文献
994.
Ba2−x
Sr
x
NaNb5O15 thin films were prepared on La0.05Sr0.95TiO3 substrates by pulsed laser deposition. The structural and ferroelectric properties of the thin films depended on substrate
temperature (T
sub) and Sr concentration. When T
sub was fixed at 700 °C, the Ba2−x
Sr
x
NaNb5O15 (x = 0, 0.6, 1.0, and 1.4) thin films exhibited a high c-axis orientation. The thin films consisted of well-developed grains and exhibited a smooth surface. The c-axis-oriented Ba0.6Sr1.4NaNb5O15 thin film with the lowest Curie temperature also exhibited a high c-axis orientation and a P-E hysteresis loop with a high ferroelectricity at T
sub 650 °C. Thus, its remanent polarization (P
r) and coercive field (E
c) were 2P
r 24.9 μC/cm2 and 2E
c 107 kV/cm, respectively. These values indicate that Ba2−x
Sr
x
NaNb5O15 has ferroelectricity in the thin film form. 相似文献
995.
We report the first experimental demonstration of longitudinal compression of laser-accelerated electron pulses. Accelerated by a femtosecond laser pulse with an intensity of 101? W/cm2, an electron pulse with an energy of around 350 keV and a relative momentum spread of about 10?2 was compressed to a 500-fs pulse at a distance of about 50 cm from the electron source by using a magnetic pulse compressor. This pulse was used to generate a clear diffraction pattern of a gold crystal in a single shot. This method solves the space-charge problem in ultrafast electron diffraction. 相似文献
996.
Jun Kanazawa Tsuyoshi Kanamori Masaki Sato Haruyuki Ishii Mikio Konno Daisuke Nagao 《Journal of nanoparticle research》2018,20(7):186
Barium titanate (BT) nanoparticles are coated by titania and modified by fluoroalkylsilane. The BT nanoparticles are incorporated into polyvinylidene fluoride (PVDF) films to obtain highly dielectric and transparent nanocomposite films at low filler loadings. Incorporation of BT nanoparticles having average sizes of 12 and 22 nm is performed. Incorporation of BT nanoparticles enhances the permittivity of PVDF films. Higher transparency of nanocomposite films is achieved by incorporating 12-nm nanoparticles compared to that by 22-nm nanoparticles. The polarisation mechanism in the nanocomposite films is examined using the Vo–Shi model. The result indicates that even a slight increase in the thickness of titania-coating layer on the BT nanoparticles increase the permittivity of the nanocomposite films. Comparison of the measured and calculated permittivities showed that the incorporation of BT nanoparticles coated with titania provides a practical approach to create transparent nanocomposite films having high permittivity. 相似文献
997.
Seiya Suzuki Yoshihiro Nemoto Natsumi Shiiki Yoshiko Nakayama Masaki Takeguchi 《Annalen der Physik》2023,535(9):2300122
Germanene is a two-dimensional germanium (Ge) analogous of graphene, and its unique topological properties are expected to make it a material for next-generation electronics. However, no germanene electronic devices have yet been reported. One of the reasons for this is that germanene is easily oxidized in air due to its lack of chemical stability. Therefore, growing germanene at solid interfaces where it is not oxidized is one of the key steps for realizing electronic devices based on germanene. In this study, the behavior of Ge at the solid interface at high temperatures is observed by transmission electron microscopy (TEM). To achieve such in situ heating TEM observation, this work fabricates a graphene/Ge/graphene encapsulated structure. In situ heating TEM experiments reveal that Ge like droplets move and coalesce with other Ge droplets, indicating that Ge remains as a liquid phase between graphene layers at temperatures higher than the Ge melting point. It is also observed that Ge droplets incorporate the surrounding amorphous Ge as Ge nuclei, thereby increasing its size (domain growth). These results indicate that Ge crystals can be grown at the interface of van der Waals materials, which will be important for future germanene growth at solid interfaces. 相似文献
998.
A Pd(OAc)2-SEGPHOS combination catalyzes the first enantioselective arylative cyclization of allenyl aldehydes with arylboronic acids to provide cis-fused five- and six-membered cyclic homoallylic alcohols. The excellent diastereo- and enantioselectivity and the fact that the reaction proceeds at room temperature in the absence of any additives make the process highly practical. 相似文献
999.
In this study, in order to address the problems with manufacturing orally rapidly disintegrating tablets (ODT) containing functional (taste masking or controlled release) coated particles, such as the low compactability of coated particles and the rupture of coated membrane during compression, a novel ODT containing taste-masked coated particles (TMP) in the center of the tablets were prepared using one-step dry-coated tablets (OSDrC) technology. As a reference, physical-mixture tablets (PM) were prepared by a conventional tableting method, and the properties of the tablets and the effect of compression on the characteristics of TMP were evaluated. OSDrC was found to have higher tensile strength and far lower friability than PM, but the oral disintegration time of OSDrC is slightly longer than that of PM following high compression pressure. Consequently, OSDrC approaches the target tablet properties of ODT, whereas PM does not. The deformation of TMP in OSDrC due to compression is slight, and the release rate of acetaminophen (AAP) from OSDrC is the same as from TMP. However, TMP on the surface of PM are considerably deformed, and the release rate of AAP from PM is faster than from TMP. These findings suggest that OSDrC technology is a useful approach for preparing ODT containing functional coated particles. Furthermore, we demonstrate that the elastic recovery of tablets can affect differences in the properties of OSDrC, PM and placebo tablets (PC). 相似文献
1000.
300 W continuous-wave operation of a diode edge-pumped, hybrid (single-crystal/ceramic) composite,Yb3+:YAG microchip laser with a 5 mm diameter and 300 microm thickness single-crystal core uniformly bonded to a water-cooled heat sink by a new Au-Sn soldering system has been demonstrated. The beam quality factor M2 follows the mode mismatch between the core and the fundamental mode and was improved to 17 with a maximum output power of 230 W. A thermally induced convex mirror with a spherical radius of curvature ranging from -2.5 to -1.5 m was observed; the radius of curvature decreases through thermal deformation of the microchip as the pump power increases. 相似文献