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991.
We observed multiple diffraction rings of a cw Ar+ laser beam from a nitrobenzene solution of saturable absorber BDN (bis-(4-dimethylaminodithiobenzil)-nickel) caused by the spatial self-phase modulation at low incident optical intensities. We obtained 37 rings for a 200-μm thick sample at an optical intensity of 38 W/mm2. The refractive-index change Δ;n and effective nonlinear refractive index n2 were determined from the number of observed rings and by the z-scan technique. We obtained large values of Δ;n∼0.1 and n2 = -2.9×;10-5 cm2/W. This large nonlinearity is attributed to a thermal effect resulting from linear absorption. 相似文献
992.
993.
994.
Morikatsu Matsunaga Yoshiaki Matsushima Hiroaki Yokoi Hajime Ohtani Shin Tsuge 《Analytical sciences》2002,18(3):277-281
Polypropyleneglycol acrylate (PGA), one of the typical acrylic oligomers manufactured industrially, was comprehensively characterized by gas chromatography (GC), supercritical fluid chromatography (SFC) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The homologous series of polypropyleneglycol diacrylate (DA), polypropyleneglycol monoacrylate (MA), and unreacted polypropyleneglycol (PG) were observed as Na adducts in the MALDI-MS spectra of the PGA samples. The relative intensities of these peaks reflect the distributions of the homologues, although their accurate quantification was generally difficult because of change in the ionization efficiency depending on the chemical structure and the molecular weight of the species. On the other hand, the DA and the MA homologues were observed in the chromatograms obtained by SFC in a temperature-programming mode, while the PG homologues were not detected under the given SFC conditions using UV detection. Here, the determination of the degree of polymerization of each component in the chromatograms was accomplished through SFC fractionation for the corresponding peaks, followed again by MALDI-TOF-MS measurement. Furthermore, most of the components in the PGA samples were almost completely separated in the resulting gas chromatograms, and their unequivocal assignments were made also using the retention data on the gas chromatograms of the SFC fractions. As for the quantitative analysis, the relative abundances among DA, MA and PG for lower degrees of polymerization can be easily calculated based on the observed gas chromatograms, whereas the distribution of DA and MA can be estimated from the observed SFC data even for the relatively higher molecular weight fractions, which are generally difficult to determine accurately by GC because of their lower volatility. These results demonstrated that even the complex PGA samples were able to be characterized in detail by using GC, SFC and MALDI-TOF-MS complementarily. 相似文献
995.
Akito Kobayashi Monehiro Azami Yoshiaki
no Tamifusa Matsuura Yoshihiro Kuroda Kazuo Miura 《Physica C: Superconductivity and its Applications》1995,250(3-4):307-319
The properties of the charge fluctuation are investigated in the d---p model with the repulsion Upd between holes on the nearest-neighbor Cu and O sites and the infinite on-site repulsion Ud at the Cu site. We calculate the charge susceptibility χc(q, iωn) and the charge correlation function Sc(q) = TΣωn χc(q, iωn). It is found that Sc(q) has a peak at the Γ point and a maximum in a ring around the Γ point. The former is due to Tχc(q, 0). Its intensity is proportional to temperature T and strongly enhanced by Upd. The latter is due to TΣωn ≠ 0 χc(q, iωn) and shows a weak T and Upd dependence. The intensity of the diffuse X-ray scattering on taking the charge fluctuation into account is also calculated. The result is consistent with the experiments in La2−δSrδCuO4. 相似文献
996.
T. Morii M. Kaburagi M. Kawaguchi T. Kitazoe M. Tomita J. Morishita M. Oka 《Zeitschrift fur Physik C Particles and Fields》1983,18(3):219-227
We have fitted the masses and elastic widths of the S=0 baryons in the context of the QCD-improved quark shell model. All states in theN=0, 1, 2 and 3 harmonic oscillator bands have been included. Three models for the decay of these states have been studied, and it is concluded that the usual spectator model for the decays must be modified. Many resonances in theN=2 and 3 bands were found to decouple from the πN channel, supporting a previous solution to the missing resonance puzzle. No evidence has been found for the tensor force, while conflicting data exist for the 3-body spin orbit term. We also have found evidence that the contact force varies with band. The (56,1?) multiplet is lower than expected. 相似文献
997.
Yoshiaki Hamada Kazuko Hashiguchi Akiko Y Hirakawa Masamichi Tsuboi Munetaka Nakata Mitsuo Tasumi Shigeki Kato Keiji Morokuma 《Journal of Molecular Spectroscopy》1983,102(1):123-147
Starting from force constant values calculated by an ab initio MO method (), and by adjusting the diagonal elements, a practical force constant matrix (F) has been reached which could explain the observed infrared and Raman spectra (in the frequency range lower than 2000 cm?1) of the gauche form of the ethylamine CH3CH2NH2 molecule and five isotopic species CH313CH2NH2, CH3CH215NH2, CH3CD2NH2, CH3CH2ND2, and CD3CD2NH2. The F matrix for the trans form of ethylamine was constructed by transferring ab initio values and by revising diagonal elements with conversion factors whose values are equal to the corresponding values of gauche form. A nearly complete set of assignments was achieved of the vibrational bands of ethylamines, observed so far in the spectral range 2000–100 cm?1. In matrix isolation spectroscopy, two bands assignable to the NH2 wagging vibrations of gauche and trans forms have been found at 775 and 782 cm?1, respectively, for CH3CH2NH2. They are at 768 and 774 cm?1, respectively, for CD3CD2NH2. From the intensity changes of these bands observed on changing the nozzle temperature in the matrix formation, the energy difference ΔE (gauche-trans) of these two conformers has been estimated to be 100 ± 10 cm?1. 相似文献
998.
We propose a dual focus optical head with a holographic optical element (HOE) which corrects spherical aberrations in order to read both 0.6 mm disks and 1.2 mm disks. The thin disks are read using transmitted light and the thick disks are read using +1st order diffracted light of the blazed HOE. The good quality of the focused spots and the focusing error signals was experimentally confirmed. No influence of unnecessary diffracted light was observed. 相似文献
999.
The semipreparative capability of the newly developed high-speed counter-current chromatograph equipped with a set of three multilayer coils has been demonstrated in separations of a variety of biological samples including triterpenoic acids, indole auxins, bacitracin, flavonoids and tetracycline derivatives, each with a suitable two-phase solvent system. The sample quantities ranging from 50 to 500 mg were efficiently separated within a few hours. The separation of tetracycline derivatives was remarkably improved by adding ammonium acetate to the solvent system. 相似文献
1000.
Mutsuo Oka 《Inventiones Mathematicae》1974,27(1-2):157-164