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A new low-coherence interferometric technique is proposed for measuring the group refractive indices of dispersive samples with high accuracy. A tandem configuration of interferometers is used to compensate for the asymmetrical distortion of interferograms that results from the broad spectrum of the light source. The group refractive index can be measured without knowledge of the geometrical thickness of the sample under test. The proposed technique can successfully measure even a thick sample. Computer calculations have shown the effectiveness of the proposed technique, which was verified by preliminary experiments; the difference between the experimental result and the catalog data was 7 x 10(-4). 相似文献
84.
Hong FL Minoshima K Onae A Inaba H Takada H Hirai A Matsumoto H Sugiura T Yoshida M 《Optics letters》2003,28(17):1516-1518
A frequency comb spanning more than one octave has been achieved by injecting the second-harmonic generation (780 nm) of a mode-locked fiber laser (1.56 microm) into a photonic crystal fiber. We propose and realize a novel interferometric scheme for observing the carrier-envelope offset frequency of the frequency comb. Frequency noise has been observed on the measured carrier-envelope offset frequency, which has been confirmed to be generated in the photonic crystal fiber by comparing the measured beat frequencies between cw lasers and frequency combs before and after the photonic crystal fiber. The mode-locked fiber laser is considered to be an important candidate for the light source used in realizing a compact optical frequency measurement system including applications in the telecommunication bands. 相似文献
85.
Gold nanowires were synthesized at 150 K by electron beam thinning of a gold thin foil in an UHV electron microscope. The gold nanowires were found to have a helical multishell structure (HMS). One particular nanowire, which was thinner than the 7-1 HMS nanowire, was found to have a tubular structure. The gold single wall nanotube is composed of five atomic rows that coil about the tube axis. The diameter was 0.4 nm and the pitch was 11 nm. The stability of the (5,3) nanotube was discussed in terms of the shear deformation of the triangular network of gold atoms. 相似文献
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Hori A Kataoka H Okano T Sakamoto S Yamaguchi K Fujita M 《Chemical communications (Cambridge, England)》2003,(2):182-183
The reversible cross-catenation of two different coordination rings (Pd(II)- and Pt(II)-linked rings) has been achieved by using the labile nature of the Pd-N interaction and efficient hydrophobic contact between the rings. 相似文献
87.
Khoroshun DV Inagaki A Suzuki H Vyboishchikov SF Musaev DG Morokuma K 《Journal of the American Chemical Society》2003,125(33):9910-9911
The reaction of a trinuclear polyhydride complex Ru3H5(C5H5)3 with cyclopentadiene, C5H6, has been studied computationally. A mechanism for the experimentally observed selective C-C bond activation is proposed. All three Ru centers participate in various steps of the mechanism. The catalytic involvement of two cluster hydrides in the transformation of the C5Hn fragment is emphasized. 相似文献
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Akiko Ohno Nana Kawasaki Kiyoshi Fukuhara Haruhiro Okuda Teruhide Yamaguchi 《Magnetic resonance in chemistry : MRC》2010,48(2):168-172
Complete NMR analysis of oxytocin (OXT) in phosphate buffer was elucidated by one‐dimensional (1D)‐ and two‐dimensional (2D)‐NMR techniques, which involve the assignment of peptide amide NH protons and carbamoyl NH2 protons. The 1H? 15N correlation of seven amide NH protons and three carbamoyl NH2 protons were also shown by HSQC NMR of OXT without 15N enrichment. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献