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511.
Isobe H Hattori Y Hayano T Kanoh H Yamamoto K Kaneko K 《Journal of colloid and interface science》2006,295(2):482-489
Attempts to prepare macroporous silica particles and metal-compound-nanoparticle-embedded silica microspheres were carried out using reactions between silicon tetrachloride and ultrasonic generating microdroplets including metal (Na, K, Al, Ni, Ti, Pt) compounds. Samples were collected by dry and wet processes. In the case of using nickel and aluminum compounds, acid-treated samples were also prepared. The obtained samples were characterized by scanning electron microscopy, X-ray fluorescence spectroscopy, powder X-ray diffractometry, mercury porosimetry, and the nitrogen adsorption method. The macroporous silica particles were prepared by removing the salt crystals, such as NaCl and KCl, formed in the silica frame. For acid-resistant metals, platinum- and titanium-compound nanoparticles are easily embedded in silica microspheres using these metal-compound solutions. For acid-soluble metals, aluminum- and nickel-compound-nanoparticle-embedded silicas were prepared by applying neutralization of the collection water. Micropores and mesopores were produced in wet-process samples. Acid treatment induced the increase of micropore volumes. 相似文献
512.
Tang J Xu J Heguri S Fukuoka H Yamanaka S Akai K Tanigaki K 《Physical review letters》2010,105(17):176402
The absolute density of states of isostructural Ba24Si100 and Ba24Ge100 near the Fermi level, which is very relevant for discussion on phonon-mediated superconductivity, is quantitatively evaluated to be 0.28 states eV?1/Ge atom and 0.18 states eV?1/Si atom by combining soft x-ray photoelectron spectroscopy and magnetic susceptibility measurements. The energetics of the anharmonic motions of the endohedral Ba atoms are also discussed on the basis of the 4d-core-level spectra. The discussion based on these important physical parameters concludes that the unique electron-phonon interactions do not occur due to the local Jahn-Teller distortion of the fragile open cage structure in the phonon-mediated BCS formalism. Compounds with a rigid cage would be essential to give rise to anticipated unique interactions as a key ingredient favored for superconducting paring. 相似文献
513.
Y Furukawa Y Nabekawa T Okino AA Eilanlou EJ Takahashi P Lan KL Ishikawa T Sato K Yamanouchi K Midorikawa 《Optics letters》2012,37(14):2922-2924
We demonstrate the generation and real-time observation of the vibrational wave packet of D(2)(+) by using a sub-10-fs extreme UV high-harmonic pump pulse and a three-color probe laser pulse whose wavelength ranges from near-IR to vacuum UV. This multicolor pump-probe scheme can provide us with a powerful experimental tool for investigating a variety of wave packets evolving with a time scale of ~20 fs. 相似文献
514.
Electrical and Optical Properties of Ferroelectric Liquid Crystals and Influence of Applied Pressure
Tsutomu Uemoto Katsumi Yoshino Yoshio Inuishi 《Molecular Crystals and Liquid Crystals》2013,570(1):137-152
Much larger dielectric constants and spontaneous polarizations are evaluated in the smectic-C phase of p-alkoxybenzylidene-p'-amino-2-chloropropyl-cinnamate (HOBACPC, OOBACPC and DOBACPC) which have dipole moments at the chiral part compared with those of p-alkoxybenzylidene-p'-amino-2-methylbutyl-cinnamate. In the mixture of D-DOBAMBC and L-DOBACPC with inverse chirality, the pitch of the helical structure is longer compared with those of original compounds. On the other hand, the dielectric constant and the spontaneous polarization of the compounds are nearly linearly dependent on the concentration of L-DOBACPC. The phase transition temperature from smectic-A to chiral smectic-C phases in DOBAMBC decreases remarkably with the mixing of organic molecules (PAA, eicosane, etc.) but increases with applied pressure. The threshold field of electro-optical effects (transmission increase, colour switching, memory effects) in DOBACPC and HOBACPC etc. is lower than that in DOBAMBC etc. in accordance with the increase of the spontaneous polarization in the former. 相似文献
515.
Kazuya Fukunaga Kazuaki Kouyama Masafumi Hashimoto Hideyuki Kunugita Kazuhiro Ema Akihiko Kikuchi Katsumi Kishino 《Journal of luminescence》2009,129(12):1735-1738
We have measured the optical properties of wurtzite InN nanocolumns and film by photoluminescence (PL) measurements at temperatures from 5 to 300 K and analyzed the PL spectra by fitting with the free-electron recombination bound (FERB) model. For the top-linked InN nanocolumns, we observed strong PL intensity compared to the InN film sample. The PL spectra were asymmetrical with low-energy tails and a red-shift of the PL peak energy position was observed with increasing temperature. However, for the separated InN nanocolumns, we observed weak PL intensity and symmetrical PL spectra. Analyzing the spectra shape of the top-linked InN nanocolumns at 5 K using the FERB model, we evaluated the intrinsic bandgap energy and carrier density of InN nanocolumns to be 0.69 eV and 2.5×1017 cm−3, respectively. 相似文献
516.
517.
518.
Simultaneous determination of a novel oral Janus kinase inhibitor ASP015K and its sulfated metabolite in rat plasma using LC‐MS/MS 下载免费PDF全文
Kazuo Oda Katsumi Mera Yasuhisa Nagasaka Kazumi Tokoro 《Biomedical chromatography : BMC》2015,29(7):967-969
A sensitive and selective liquid chromatography with tandem mass spectrometry (LC‐MS/MS) was developed for determining the concentrations of novel Janus kinase inhibitor ASP015K and its sulfated metabolite M2 in rat plasma. This method involves solid‐phase extraction (SPE) from 25 μL of rat plasma. LC separation was performed on an Inertsil PH‐3 column (100 mm L ×4.6 mm I.D., 5 µm) with a mobile phase consisting of 10 mM ammonium acetate and methanol under linear gradient conditions. Analytes were introduced to the LC‐MS/MS through an electrospray ionization source and detected in positive‐ion mode using selected reaction monitoring. Standard curves were linear from 0.25 to 500 ng/mL (r ≥0.9964). This assay enabled quantification of ASP015K and M2 at a concentration as low as 0.25 ng/mL in rat plasma. Validation data demonstrated that the method is selective, sensitive and accurate. Further, we also successfully applied this method to a preclinical pharmacokinetic study in rats. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
519.
520.
Yusuke Ujihira Toshihiko Ryuo Yoshinori Kobayashi Tsutomu Nomizu 《Applied physics. B, Lasers and optics》1978,16(1):71-74
Sizes of free volume were quantitatively calculated for 42 organic liquids by means of the Kincaid and Eyring method. The
results were discussed in relation to the pick-off annihilation lifetime of ortho-positronium in molecular liquids. The presence
of strong correlation was found between them, this fact made us conclude that the free volume size was the most essential
physical parameter, which determines the pick-off annihilation rate of ortho-positronium. The problem that the calculated
free volume was too small for the existence of ortho-positronium could be eliminated by the equilibristic formation of a bubble
around ortho-positronium. Correlation was shown between the free volume radii and bubble radii. Our discussion will likely
apply to a wider area for the analysis of empirical data on pick-off rate of ortho-positronium in organic liquids and to the
experimental investigation of the pick-off process of ortho-positronium annihilation. 相似文献