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991.
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994.
Keiichi Tanaka Koichi Yamada Toru Nakagawa Kozo Kuchitsu John Overend 《Journal of Molecular Spectroscopy》1975,54(2):243-260
A high-resolution infrared spectrum of H2CO was measured in the range from 2600 to 3300 cm?1. Vibration-rotation lines assigned to the combination bands ν2 + ν3 (a-type) and ν2 + ν6 (b-type) were analyzed as asymmetric-rotor bands by taking account of the Coriolis interactions among the ν2 + ν3, ν2 + ν6, and ν2 + ν4 states, though none of the ν2 + ν4 band lines have yet been definitely identified. The main results in cm?1 units (with 2.5 times standard errors in the last digits given in parentheses) are: ν0 = 3238.45(1), A - B?= 8.252(3), B?= 1.2053(2), and B - C = 0.1719 (assumed) for ν2 + ν3; ν0 = 3000.10(1), A - B?= 8.125(46), B?= 1.2075(5), and B - C = 0.1693(14) for ν2 + ν6; and ν0 = 2904.6(48), A - B?= 8.225(54), B?= 1.2023(20), and B - C = 0.1522 (assumed) for ν2 + ν4; the effective Coriolis interaction terms are: ξ26,24a = 10.10(3)cm?1 and ξ23,26c = 0.96(3)cm?1 under the assumption that ξ23,24b = 1.2841cm?1. A second combination band 2ν2 + ν6 measured with lower resolution gave ν0 = 4734.81(6)cm?1. 相似文献
995.
The Mössbauer spectroscopy was applied on a random mixture of two kinds of magnetic ions with competing anisotropies, Fe1?xCoxCl2·2H2O. The Mössbauer spectra observed in the Co(Fe)-rich antiferromagnetic (AF) phase near the tetracritical point show that, although the m2(m1) spin component parallel to the easy axis of pure FeCl2·2H2O(CoCl2·2H2O) has no long-range order in this phase (from the neutron diffraction experiment), the m2(m1) spin component contributes to the magnetic hyperfine field at 57Fe nuclei as well as the m1(m2) spin component (which has a long-range order). This fact indicates that the m2(m1) spin components exists in the Co(Fe)-rich AF phase near the tetra-critical point at least in a time scale of ~ 10?8s. This result predicts that the antiferromagnetic ordering in the Co(Fe)-rich AF phase is a new type one. The new phase observed in the intermediate concentration region is demonstrated as the “mixed ordering” phase. 相似文献
996.
Low dielectric loss polyethylenes have been produced by γ-radiation polymerization of oxygen-free ethylene monomers. Dielectric measurements were made at 500 MHz and 20°C. The lowest dielectric loss tangent of the polyethylene was 3.3 × 10?5. Polar groups contributing to the dielectric loss have been found to be carbonyl groups, terminal vinyl groups, methyl groups, and hydroxyl groups contained in the polyethylene. The contribution of each group to the loss tangent has been calculated from a comparison of the variation of the loss tangent with the content of each group as determined by infrared analysis. It has been found that the reduction of the loss tangent is mainly due to the decrease in the concentrations of the carbonyl groups and the terminal vinyl groups and that the presence of a considerable amount of the hydroxyl groups prevents a further reduction of the loss in the polyethylenes. The results obtained from the analysis of the radiation-polymerized polyethylenes were applied to commercially available polyethylenes. 相似文献
997.
A dual ion-selective electrode gas chromatographic detector which allows the simultaneous detection of chlorine- and bromine-containing compounds through two-channel operation is described. Components eluted from the g.c. column are hydrogenated, the hydrogen chloride and hydrogen bromide produced being absorbed in a standard solution of halide; the ion concentrations in the resulting solution are monitored by chloride- and bromide-selective electrodes. The dual electrode detector gives two chromatograms simultaneously, one selective for chlorine- and bromine-containing compounds and the other for bromine-containing compounds. The response ratio, i.e., the peak area of the readout from the chloride channel divided by that from the bromide channel for the same compound, gives valuable information. The Cl/Br ratio in an eluted molecule can be determined accurately from the response ratio if a standard reference compound is injected simultaneously. 相似文献
998.
The microwave and millimeter wave spectra of HNCS in the three bending excited states, v4 = 1, v5 = 1, and v6 = 1, have been measured. The qR0, qR1, and qR2 branches for each of these three states and the qR3 branch for the lowest excited state have been assigned. Effective rotational and centrifugal distortion constants have been determined for each vibrational and Ka-rotational sub-state. Two local resonances, caused by the Coriolis induced asymmetry interaction and a b-type Coriolis resonance, allow unambiguous confirmation of the assignment of the state v6 = 1, the first excited state of the out-of-plane vibration. 相似文献
999.
Koichi Ogiue 《Annali di Matematica Pura ed Applicata》1968,80(1):387-397
Summary Theory of immersions satisfying the condition that tangent spaces to an immersed submanifold are invariant under the curvature
transformation. 相似文献
1000.