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171.
N. A. Inogamov A. Ya. Faenov V. V. Zhakhovskii I. Yu. Skobelev V. A. Khokhlov Y. Kato M. Tanaka T. A. Pikuz M. Kishimoto M. Ishino M. Nishikino Y. Fukuda S. V. Bulanov T. Kawachi Yu. V. Petrov S. I. Anisimov V. E. Fortov 《等离子体物理论文集》2011,51(4):361-366
Laser‐matter interaction is defined by an electronic band structure of condensed matter and frequency ωL of electromagnetic radiation. In the range of moderate fluences, the energy absorbed by electrons from radiation finally thermalizes in the ion thermal energy. The thermalization processes are different for optical as compared with X‐ray quanta and for metals relative to semiconductors and dielectrics, since the light absorption and electron‐electron, electron‐ion dynamics are sensitive to the electron population in a conduction band and the width of a forbidden gap. Although the thermalization processes are different, the final state is simply a heated matter. Laser heating creates powerful stresses in a target if duration of a laser pulse τL is short in acoustic time scale. Nucleation and material removal take place under such stresses. Such way of removal is called here the spallative ablation. Thus the spallative ablation is an ablation mechanism universally important for qualitatively different materials and quanta (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
172.
Masahiro Yamashita Daisuke Kawakami Satoshi Matsunaga Yoshio Nakayama Mari Sasaki Shinya Takaishi Fumiyasu Iwahori Hitoshi Miyasaka Ken‐ichi Sugiura Yoshiki Wada Hiroshi Miyamae Hiroyuki Matsuzaki Hiroshi Okamoto Hisaaki Tanaka Kazuhiro Marumoto Shin‐ichi Kuroda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2004,116(36):4867-4871
173.
Pulsed laser deposition of iron atoms on graphite substrates was performed to produce iron carbide films. Mössbauer spectra of the sample revealed that iron carbide was produced on the substrate surface and that an α-Fe layer was produced above the iron carbide layer. When the substrate temperature was maintained at 300 K, the iron carbide layer had a hyperfine magnetic distribution because it contained high density of defects. Laser deposition of Fe at 570 K produced cementite Fe3C with fewer defects due to enhancement of thermal reactions or annealing of the films. The orientation of hyperfine field of the Fe3C film was parallel to the substrate surface. 相似文献
174.
Supramolecular polymer gels from polystyrene bearing cyclic amidine Group and acrylic acid/n‐butyl acrylate copolymers
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Mina Sakuragi Naoto Aoyagi Yoshio Furusho Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2016,54(6):765-770
We have prepared supramolecular polymer gels by mixing solutions of a polystyrene bearing cyclic amidine pendant groups (Poly‐A) and copolymers of acrylic acid and n‐butyl acrylate (Poly‐C), followed by evaporation. FT‐IR analysis indicated that the gels were formed through three‐dimensional network of the amidinium‐carboxylate salt bridge. DSC study showed that the Poly‐A and the Poly‐C were miscible when the salt bridge content was high. On the other hand, the mixtures with small salt bridge content showed phase separation. Dynamic shear measurements showed that the gel prepared from Poly‐A and Poly‐C with acrylic acid unit content of 15% had G' higher than G″ over a temperature range of ?22 °C to 32 °C, in which the G' value reached almost 1 MPa. The gel had a crossover point of G' and G″ at 32 °C, very close to room temperature, which suggested facile processability. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 765–770 相似文献
175.
Road signs must provide a conspicuous signal to a wide variety of drivers over a broad range of environmental and geometric
conditions. Recently, there are an increasing number of applications in which light emitting diodes (LEDs) are used as the
light source, including critical transportation signaling. In the presence of fog, the resulting visual signal is disturbed
due to light scattering by airborne water droplets. By measuring LED brightness with human spectral sensitivity in various
densities and various droplet sizes (10, 30, 50, and 100 μm), it is understood that the particle size distribution (fog droplet
size) and density of fog does affect visibility in fog. The colored LEDs that contain a yellow component had high brightness
evaluation, blue component had low brightness evaluation in all densities and different droplet sizes. The result in this
paper can contribute to air and land traffic safety and the prevention of accidents. 相似文献
176.
177.
Schreiner PR Fokin AA Lauenstein O Okamoto Y Wakita T Rinderspacher C Robinson GH Vohs JK Campana CF 《Journal of the American Chemical Society》2002,124(45):13348-13349
Pseudotetrahedral, conformationally as well as configurationally stable 1-bromo-3-chloro-5-fluoro- (4) and 1-bromo-3-chloro-5-fluoro-7-iodoadamantane (5) (and some related compounds) were prepared by our recently devised phase-transfer catalytic halogenation protocol; the optical antipodes of 4 were separated by HPLC on chiral phase in ee > 99%, and the absolute configurations were assigned by matching observed and computed circular dichroism spectra. Structure 5 is the first chiral aliphatic hydrocarbon containing all stable (nonradioactive) halogens; its structure was proven by NMR spectroscopy and by X-ray crystal data. We emphasize that the combination of experiment and theory is very powerful in assigning absolute configurations even for molecules without typical chromophors, with small values for the optical rotation, and without an atom at the stereogenic center. 相似文献
178.
Yagi S Iwanaga T Kojima H Shoji Y Suzuki S Seno K Mori H Tokura Y Takigawa M Moriwaki S 《Photochemistry and photobiology》2002,76(6):669-671
We have developed a UV monitor with polycrystalline (poly-) gallium nitride (GaN) UV sensors and evaluated its performance from the viewpoint of its effectiveness for use with photosensitive dermatosis patients. The poly-GaN UV sensor is sensitive to UV light from 280 to 410 nm even without optical filters. The UV monitor is a portable self-data-acquisition instrument with a minimum detection level (defined as average UV intensity over 290 to 400 nm) of 2 microW/cm2 and can store UV dose data for 128 days. It allows easy measurement of four orders of magnitude of ambient UV intensity and dose from indoor light to direct solar radiation in summer. Trial use of the UV monitor by five xeroderma pigmentosum patients started in June 2000 and was carried out for 1 year. It was demonstrated that the UV monitor was useful in improving their quality of life. 相似文献
179.
A lipid (1)-coated lipase can catalyze the oligomerization of diethoxydimethylsilane (DEDMS) in isooctane containing 2wt% water, where the polymerization occurs at the OH group of the coating lipid (1) in the enzyme cavity. 相似文献
180.
Kinetic studies of enzymatic DNA cleavage reactions (the enzyme binding, hydrolysis along DNA strands, and then release of the enzyme from the completely hydrolyzed ssDNA) were carried out on a 27 MHz quartz-crystal microbalance. 相似文献