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91.
Lansioside A, a novel triterpene amino-sugar glycoside, is isolated from Lansium domesticum and its full structure including absolute configuration is established by the chemical derivation and spectral study.  相似文献   
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The distribution in the silicon epitaxial growth from SiCl4 and hydrogen are observed in situ by IR absorption spectroscopy. Two methods are used complementarily, one is IR spectroscopy of reactants extracted from the reactor by a fine quartz tube which is not disturbing the reactions, and gives knowledge about the local distribution, the other is direct IR spectroscopy of hot reactants in the reactor which is useful to ascertain the results at the real high temperature situation. The intermediate species are SiHCl3, SiH2Cl2 which is estimated from the induced emission bands at 500 and 570 cm-1. HCl is a dominant waste product and contributes to reverse reactions. To investigate the reaction, HCl is intentionally injected into the reacting gas. This kind of injection method may also be very effective to analyze the reactions using other reactants such as SiCl4, SiHCl3 and SiH2Cl2.  相似文献   
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Nitric oxide reacts efficiently with alkynyllithium at low temperature producing 1,2,3-oxadiazole 3-oxides in good yields.  相似文献   
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Nishizawa N  Takahashi K 《Optics letters》2011,36(19):3780-3782
Time-domain absorption spectroscopy was demonstrated using a wideband, rapid wavelength-tunable, narrow-linewidth source based on an Er-doped ultrashort pulse fiber laser system. The spectrum of the Raman-shifted ultrashort soliton pulse was compressed using a comb-profile dispersion increasing fiber. Rapid wavelength sweeping was demonstrated using an electro-optical intensity modulator. The absorption spectrum of CH(2)Cl(2) liquid at 1625-1780 nm was observed in a 10 μs time-domain measurement.  相似文献   
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1-μm-thick polar-axis-oriented CaBi4Ti4O15 (CBTi144) films were fabricated by control of nucleation and growth in alkoxy-derived non-crystalline layers on Pt foils. The oxygen ambient during pre-baking impacted both the cross-sectional microstructure and the crystallographic orientation. The 1-μm-thick film showed relatively high intensities of (100)/(010) diffraction lines in the X-ray diffraction profile and simultaneously had a closely packed dense structure in the transmission electron microscopy cross-sectional profile. Resultantly, the leakage current density decreased to about 7×10-8 A/cm2 at 10 V. The piezoelectric constant d33 was determined to be 260 pm/V at a maximum poling voltage of 60 V by measurements using piezoelectric force microscopy. PACS 77.55.+f; 77.84.-s; 77.65.-j; 68.55.Jk  相似文献   
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Outlier flooding method (OFLOOD) is an efficient conformational sampling method developed by the authors. In the present study, to further enhance the conformational sampling efficiency, a set of parameters (temperatures and pressures) specified as inputs in the original OFLOOD were shuffled before restarting the short-time molecular dynamics (MD) simulations. Because of the diversity of these parameters, it was confirmed that the extended OFLOOD becomes superior to the original one in finding the folding pathways of Trp-cage. © 2019 Wiley Periodicals, Inc.  相似文献   
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