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951.
This paper introduces explicit conditions for some natural family of polynomials to define Pisot or Salem numbers, and reviews
related topics as well as their references. 相似文献
952.
Toshinari Isono Takayuki Ikeda Ryuji Aoki Kenji Yamazaki Toshio Ogino 《Surface science》2010,604(21-22):2055-2063
Atomic force microscopy (AFM) was used to characterize morphology and chemistry on step-controlled single crystalline sapphire (0001) surfaces. Hydrophilicity on the surface can be evaluated using frictional force imaging. A sapphire surface that is covered with bunched steps accompanied with crossing steps clearly exhibits the phase-separation into two domains with different hydrophilicity, where an almost hydrophobic domain forms inside a hydrophilic area. By analyzing the histogram of the step height, we concluded that the difference in the hydrophilicity is associated with the surface reconstruction. We found that the phase-separation characterized by the hydrophilicity and charge potential self-organizes on the sapphire surface with specific step arrangements. We demonstrated selective adsorption of biomolecules on step-controlled surfaces as an example of the application. 相似文献
953.
In tilted magnetic fields, vortices in anisotropic superconductors form one-dimensional arrangements, called vortex chains.
We have visualized vortex chains by Bitter decoration and magneto-optical technique. The fundamental energy scale for the
attractive interaction between pancake and Josephson vortices is evaluated by observing vortex chains under various conditions.
We also explore how the vortex chains evolve when the large in-plane field is applied or when the anisotropy parameter of
the system is changed 相似文献
954.
Mitsumasa Taguchi Hideki Namba Yasushi Aoki Katsutoshi Furukawa Shin-ichi Ohno 《Radiation Physics and Chemistry》1999,55(5-6):511-514
The ionization distribution in Ar gas by 175 MeV Ar ion was measured, and reduced to the energy density as a function of the radial distance in water. The energy density within the radial distance smaller than 294 nm decreased proportionally to the inverse of the square of the distance. Beyond this distance, however, the energy density decreased more steeply. The deposited energy except in the core region of the track amounts to 89% of linear energy transfer (LET). 相似文献
955.
Kinetic equations with relaxation collision kernels are considered under the basic assumption of two collision invariants,
namely mass and energy. The collision kernels are of BGK-type with a general local Gibbs state, which may be quite different
from the Gaussian. By the use of the diffusive length/time scales, energy transport systems consisting of two parabolic equations
with the position density and the energy density as unknowns are derived on a formal level. The H theorem for the kinetic
model is presented, and the entropy for the energy transport systems, which is inherited from the kinetic model, is derived.
The energy transport systems for specific examples of the global Gibbs state, such as a power law with negative exponent,
a cut-off power law with positive exponent, the Maxwellian, Bose–Einstein, and Fermi–Dirac distributions, arepresented.
MSC classification (2000): Primary: 82C40, 35B40; Secondary: 35K55, 45K05, 82D05, 85A05x 相似文献
956.
A new method for pyrophosphate bond formation in the solid phase was developed by use of phosphoramidite derivatives, which were found to be readily converted by reaction with 6-trifluoromethyl-1-hydroxybenztriazole via an O-N phosphoryl rearrangement into pentavalent phosphotriester intermediates. These intermediates proved to react smoothly with not only phosphomonoesters but also phosphodiesters to give protected pyrophosphate derivatives which, in turn, could be easily deprotected to give the desired pyrophosphate derivatives. 相似文献
957.
958.
Tatsuro Ouchi Tomohiro Kontani Rie Aoki Toshifumi Saito Yuichi Ohya 《Journal of polymer science. Part A, Polymer chemistry》2006,44(21):6402-6409
To develop novel biomedical soft materials with degradability, amphiphilic poly(L ‐lactide)‐grafted dextrans (Dex‐g‐PLLAs) of relatively high sugar unit contents were synthesized with the trimethylsilyl protection method. The characteristic properties of solution‐cast films prepared from the obtained Dex‐g‐PLLAs were investigated. The water absorption and degradation rate of the Dex‐g‐PLLA films increased with increasing sugar unit content. The morphology of the bulk phase and top surface of the Dex‐g‐PLLA films was evaluated with transmission electron microscopy and atomic force microscopy, respectively. The bulk phase of the Dex‐g‐PLLA films with a sugar unit content of 16–25 wt % was found by transmission electron microscopy to form a lamellar type of phase‐separated structure composed of approximately 80–100‐nm‐wide nanodomains because of their amphiphilic and branched structures. The hydrophobic top surface for a Dex‐g‐PLLA film with a sugar unit content of 25 wt % covered with PLLA segments was confirmed by atomic force microscopy phase images to be easily converted to a wettable top surface covered with hydrophilic dextran aggregates showing an 8–10‐nm‐wide honeycomb pattern by means of annealing in water. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6402–6409, 2006 相似文献
959.
Rafael J. G. Rubira Sabrina A. Camacho Pedro H. B. Aoki Mateus D. Maximino Priscila Alessio Cibely S. Martin Osvaldo N. Oliveira Jr. Francisco M. Fatore Fernando V. Paulovich Carlos J. L. Constantino 《Colloid and polymer science》2014,292(11):2811-2820
The detection of trace amounts of pesticides is essential for the quality control of waters, particularly with their inevitable increasing use with the growing demand for food. In this study, we report on the detection of atrazine, a highly toxic herbicide, down to 5?×?10?12 M, which is sufficient to monitor the quality of drinking water even according to the most stringent international regulations. Such detection was performed with surface-enhanced Raman scattering (SERS) in atrazine incorporated into silver nanoparticles (AgNPs) colloids, with the SERS spectra being treated with Sammon’s mapping, an information visualization technique. In addition to providing a fingerprint of the atrazine molecules, SERS is advantageous in comparison with impedance spectroscopy and cyclic voltammetry applied to a sensor array of units made with layer-by-layer (LbL) films containing AgNPs and AuNPs. The combined use of SERS and information visualization methods is promising for monitoring water quality with regard to other pesticides, which may even approach single molecule detection. 相似文献
960.