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941.
Akihiro Yamamoto Chih-Che Kuo Kei Sunouchi Satoshi Wada Ichirou Yamaguchi Hideo Tashiro 《Optical Review》2001,8(1):59-63
We developed a high speed and high resolution surface shape measurement system based on wavelength scanning interferometry with an electronically tuned Ti:sapphire laser. This laser emits pulses and the wavelength of each pulse can be tuned arbitrarily within 680 nm and 1056 nm. We also designed a high speed multiport CCD camera as a detector. This camera is synchronized with wavelength scanning of the laser at the frequency of 250 Hz. We could measure the object shape with a height resolution of 3.05 μm at the tuning range from 740.0 nm to 842.3 nm. By simple parabolic curve fitting to the Fourier peak of interference signals from each CCD pixel, the height resolution has been improved to the order of submicrometers. 相似文献
942.
Y. Yamaguchi J. Gspann 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):103-106
Large-scale molecular dynamics simulations with high acceleration energy on a diamond surface were performed in order to investigate
the surface erosion process. Accelerated argon or CO2 clusters (∼960 atoms, 100 keV/cluster) impacted on the (111) surface of diamond which consisted of more than 1,000,000 carbon
atoms. A typical hemispherical crater appeared about 0.7 ps after the impact, and two or three-layered shockwaves were formed
and propagated to certain directions, but the crater was immediately filled up with the fluidized hot carbon material due
to the collective elastic recovery before the reflection of the shockwave. The impact energy of the cluster was at first transferred
mainly as kinetic energy of the diamond surface in a short time, and the potential energy was activated later. The activated
carbon and oxygen atoms from the impact cluster stimulated the evaporation from the diamond surface for the CO2 cluster impact while the evaporation seemed to be suppressed by the argon atoms themselves for the argon cluster impact.
Received 22 November 2000 相似文献
943.
Surface Shape Measurement by Phase-Shifting Digital Holography 总被引:3,自引:0,他引:3
Surface contouring by phase-shifting digital holography is proposed that provides surface height from a change of reconstructed phase due to tilting of the object illumination. After phase-unwrapping it directly delivers surface shape. Its sensitivity depends on the tilting angle as well as on the initial incident angle. Although the sensitivity is the same as in the conventional fringe projection, a simpler setup is used without imaging lens and measurement depth is increased due to numerical focusing. We also performed noise suppression by employing nonlinear image-data compression technique that considers amplitude values and attained standard height deviation less than 30 #x03BC;m from a flat surface. 相似文献
944.
S. Suzuki H. Yamaguchi T. Ishigaki R. Sen H. Kataura W. Krätschmer Y. Achiba 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):369-372
Time evolution of emission by carbon nanoparticles generated with a laser furnace technique was investigated with a high-speed
video camera. Assuming blackbody radiation formula for small spherical particle, the internal temperature of these carbon
nanoparticles was determined as a function of time delay (Δt) after laser vaporization. It was found that the internal temperature of them drastically decreased at Δt < 400μs through collision with the surrounding rare gas inside the furnace. On the other hand, in particular laser vaporization
condition where yields of C60 and other higher fullerenes in the soot were found to be high, an increase in the blackbody emission intensity could be recognized
for longer wavelength ( 660 < λ < 830 nm) at Δt > 400μs. This finding suggests that a certain exothermic process related to the formation of C60 and other higher fullerenes should occur at Δt > 400μs inside the furnace. 相似文献
945.
We have measured the reaction cross section σR of 17C on the carbon target at the intermediate energy of 97A MeV by using transmission method.finite-range Glauber model has been employed to investigate the density distribution of 17C by fitting the present result and the previous result of interaction cross section σI.By contrast with the result from the analysis of σI,a tail in the neutron density distribution of 17C is found necessary to interpret the present result.Considering the configuration of the valence neutron,a dominant 1d5/2(77±21%)occupancy is found,which is in agreement with results of momentum distribution measurements. 相似文献
946.
1 : 1 mixtures of aminomethylenehelicene (P)-tetramer and (M)-pentamer with terminal C16 alkyl groups in fluorobenzene showed structural changes between hetero-double-helices B and C and random-coils 2A. Figure-eight thermal hysteresis appeared when the solution was cooled and heated at a constant rate and involved the crossing of cooling and heating curves in Δε/temperature profiles. This unusual thermal hysteresis emerged in the intermediate state between counterclockwise and clockwise thermal hystereses. This phenomenon arose from the competition between self-catalytic reactions to form B and C from 2A. Significant effects of terminal C16 alkyl groups on the thermodynamic and kinetic phenomena are also described.1 : 1 mixtures of aminomethylenehelicene (P)-tetramer and (M)-pentamer with terminal C16 alkyl groups in fluorobenzene showed structural changes between hetero-double-helices B and C and random-coils 2A. 相似文献
947.
Hiroaki Yamaguchi Asuka Fujikawa Hajime Ito Nobuaki Tanaka Ayako Furugen Kazuaki Miyamori Natsuko Takahashi Jiro Ogura Masaki Kobayashi Takehiro Yamada Nariyasu Mano Ken Iseki 《Biomedical chromatography : BMC》2013,27(4):539-544
A column‐switching liquid chromatography/electrospray ionization tandem mass spectrometry to determine paclitaxel and its metabolites, 6α‐hydroxypaclitaxel and p‐3′‐hydroxypaclitaxel, in human plasma was developed. The analytical system had a Shim‐Pack MAYI‐ODS (10 × 4.6 mm i.d.) trapping column with deproteinization ability that concentrates analytes and removes water‐soluble components. This method covered a linearity range of 5–5000 ng/mL of concentrations in plasma for paclitaxel, a range of 0.87–870 ng/mL for 6α‐hydroxypaclitaxel and a range of 0.87–435 ng/mL for p‐3′‐hydroxypaclitaxel. The intra‐day precision and inter‐day precision of analysis were less than 11.1%, and the accuracy was within ±14.4% at concentrations of 5, 50, 500 and 5000 ng/mL for paclitaxel, 0.87, 8.7, 87 and 870 ng/mL for 6α‐hydroxypaclitaxel, and 0.87, 8.7, 87 and 435 ng/mL for p‐3′‐hydroxypaclitaxel. The total run time was 30 min. Our method was successfully applied to clinical pharmacokinetic investigation. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
948.
Dr. Satoshi Yamaguchi Kazuki Chujo Noriyuki Ohashi Dr. Kosuke Minamihata Prof. Dr. Teruyuki Nagamune 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(12):e202103941
There is growing demand for the precise remote control of cellular functions in various fields. Herein, a method for caging mammalian cells by coating with photodegradable protein-polymer hybrid shells to photo-control their functions without genetic engineering is reported. A layer-by-layer assembly of photocleavable synthetic materials through biotin-streptavidin (SA) binding was employed for cell coating. The cell surfaces were first biotinylated with photocleavable biotinylated poly(ethylene glycol)(PEG)-lipid and then coated by repeatedly layering SA and micelles of the PEG-lipid and photocleavable biotinylated four-arm PEG. The cell extension and adhesion were suppressed with the shells and then triggered with the degradation of the shells by light exposure. Macrophage phagocytosis was also stopped by caging with the shells and restarted by light-guided uncaging. This study provides the first proof of principle that cellular functions can be remotely controlled by steric hinderance of cell surfaces with photodegradable materials. 相似文献
949.
Optical Review - As part of our ongoing research on lensless imaging with a Fresnel zone aperture (FZA), we propose a method of improving resolution with higher FZA harmonics. Although previous... 相似文献
950.