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991.
Rushford MC Britten JA Barty CP Jitsuno T Kondo K Miyanaga N Tanaka KA Kodama R Xu G 《Optics letters》2008,33(16):1902-1904
We introduce a four-pass laser pulse compressor design based on two grating apertures with two gratings per aperture that is tolerant to some alignment errors and, importantly, to grating-to-grating period variations. Each half-beam samples each grating in a diamond-shaped compressor that is symmetric about a central bisecting plane. For any given grating, the two half-beams impinge on opposite sides of its surface normal. It is shown that the two split beams have no pointing difference from paired gratings with different periods. Furthermore, no phase shift between half-beams is incurred as long as the planes containing a grating line and the surface normal for each grating of the pair are parallel. For grating pairs satisfying this condition, gratings surfaces need not be on the same plane, as changes in the gap between the two can compensate to bring the beams back in phase. 相似文献
992.
Yamauchi K Okonogi M Kurosu H Tansho M Shimizu T Gullion T Asakura T 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,190(2):327-332
(17)O chemical shifts of Ala-Ala-Ala, with parallel and anti-parallel beta-sheet structures, are observed using a 930-MHz high-resolution solid-state NMR spectrometer. Ala-Ala-Ala serves as a model sheet-forming peptide because it can be easily prepared as either a parallel or an anti-parallel beta-sheet structure. Spectral differences between the two samples are observed which arise from molecular packing differences between the two sheet structures. DFT chemical shift calculations are performed for the two samples, and the calculated spectra are in good agreement with the experimental spectra. The DFT calculations provide insight into the nature of the chemical shift differences observed between the two sheet structures. 相似文献
993.
Kazuo Kamigaki Masatoshi Shono Hajime Yoshida Shunya Abe Takejiro Kaneko 《Journal of magnetism and magnetic materials》1987,70(1-3):218-220
Magnetic susceptibility and crystal structure were studied on CrSb1−xAs0.6, structural transformation occurs between MnP-type and NiAs-type at 270 K, the Néel temperature is 300 K. Paramagnetic moments of the system are 2.45−2.7μB/Cr, considerably larger than antiferromagnetic moments. 相似文献
994.
Haruhiko Ito Yasushi Ozaki Takashi Nagata Tamotsu Kondow Kozo Kuchitsu Kazuo Takatsuka Hiroki Nakamura Yoshihiro Osamura 《Chemical physics》1985,98(1):81-87
The potential energy curves of the low-lying X2Σ+, A2πi, B2Σ+,4Σ+, and 4π states of CN are calculated by the MC SCF (CAS SCF) method. Their vibrational levels and the molecular constants obtained are in good agreement with those determined in our recent experimental analysis of the CN (B2Σ+-X2Σ+) emission spectrum. several intensity anomalies in the observed spectrum are ascribed to perturbations between the B2Σ+ and 4π states with the following vibrational quantum numbers: (υB, υπ)=(9,x), (11, x+2), (12, x+3), (14, x+6), (17, x+11), and (18, x+13), where x = 0 is the most probable assignment. Likewise, the perturbations between the B2Σ+ and 4Σ+ states with (υB, υΣ) = (11, y), (13, y+3) are interpreted as y = 8±1. 相似文献
995.
Ajit Kumar Chakravarty Binayaku Das Kazuo Masuda Hiroyuki Ageta 《Tetrahedron letters》1990,31(52):7649-7652
The structure of chiratenol (2), the first representative of a new triterpenoid skeletal type, has been established on the basis of 1D and 2D NMR spectroscopy. 相似文献
996.
997.
Tetsuo Asakura Makoto Demura Yasuo Watanabe Kazuo Sato 《Journal of Polymer Science.Polymer Physics》1992,30(7):693-699
The dynamical behavior of the Bombyx mori silk fibroin chain and of absorbed water in silk fiber, film, and powder has been studied by 1H pulsed nuclear magnetic resonance (NMR). Segmental motions do not occur and only the rapid rotation of the methyl groups of alanine residues is observed from ?120 to 130°C. This is independent of the conformation or form of the silk fibroin samples. Magnetization of dry silk fibroin by the solid-echo method shows a single Gaussian decay, while two components are observed in the solid-echo signals of films containing 6–10 w/w% water. An immobile component with a T2 value of 11 μs is attributed to silk fibroin, and the mobile component to bound water. The T2 of the latter varies from 50 to 200 μs, depending on the sample. The dynamical behavior of water trapped in the film is discussed on the basis of these T2 values. 相似文献
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