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1.
Zirconium or aluminum O-enolates undergo selenenylation with PhSeBr to give α-(phenylselenenyl) ketones in good to excellent yield.  相似文献   
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Using a focussing crystal spectrometer with photoelectric registration theK-emission spectrum of fluorine in solid lithium fluoride (=18.3 Å) was studied. If the spectrum is excited by Co or CuL-radiation or bremsstrahlung of a W-target the satellitesK 3 andK 4 appear with considerable intensity, whereas they appear only faintly ifL-radiation of Fe is used for excitation. In agreement with these observations the calculated threshold energies of the satellites are near the photon energy of FeL 1, 2. The measured energies of the components agree with values obtained from the energies of the singly and doubly ionized F ion as calculated by means of optical data. The results show that the satellitesK 3 andK 4 in the spectrum of fluorine in solid LiF correspond to transitions in the doubly ionized F-ion.  相似文献   
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In an earthquake occurring directly under a city, such as the Hanshin–Awaji great earthquake, the first axial longitudinal impact induced from the source may create fatal damage to the architectural columns. This phenomenon has been confirmed by a theoretical analysis based on elastic wave propagation in columns fixed at both ends. In this paper, the stress intensification behavior in the columns under axial impact is verified by the high-speed photoelastic experiments in combination with semiconductor strain gage and by the theoretical analysis of the longitudinal stress wave analysis method.  相似文献   
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Deformation of an m-dimensional submanifold immersed in a Euclidean n-space is studied when the Gauss image does not move pointwise. The present paper is the third one and contains deformations where the tensor of deformation satisfies some differential equations, normal deformations and deformations of totally-real submanifolds in a complex space.  相似文献   
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Spectral quality and reliability of four kinds of127 I 2 cells for an wavelengtn standard were investigated. A 20 year old 10 cm long sealed off iodine cell has shown its long life and had sufficient absorption characteristics comparable to the newly made three cells in regard to spectral line width and signal-to-noise ratio of the absorption signal. A dispersion of absolute frequencies of the three cells including the 20 year old cell is in a range of 35 kHz, which is equivalent to a frequency reproducibility of 7.4X10-11. A compact iodine stabilized 633 nm He-Ne laser with a 23 cm long resonator and 4 cm iodine cell has been developed. Its frequency stability has been estimated to be 9X10-13 by the Allan deviation at integration time of 4000 s. The laser supplies 14 wavelength standards being locked at iodine absorption lines from a ton.  相似文献   
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Summary A subalgebrag ofgl(n, R) which admits no proper invariant subspace in Rn and contains a subalgebra of a special kind is studied. It is concluded that only four cases are possible if n is even, and only two if n is odd. To Enrico Bompiani on his scientific Jubilee  相似文献   
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Sediments, as sources of microorganisms, were added to two kinds of media, 1/5 ZoBell 2216E and a solution of inorganic salts, which contained inorganic arsenic(III), inorganic arsenic(V), methanearsonic acid, dimethyl- arsinic acid, trimethylarsine oxide, tetramethylarsonium salt or arsenocholine. After 17 days of incubation at 20 °C, the arsenicals that had accumulated in the microorganisms were analysed by high-performance liquid chromatography (HPLC). While the more toxic arsenicals [inorganic arsenic(III), inorganic arsenic(V), methanearsonic acid, dimethylarsinic acid] were not converted in the microorganisms, trimethylarsine oxide and tetramethylarsonium salt were considerably degraded to inorganic arsenic(V), and arsenocholine to arsenobetaine. Arsenobetaine that had accumulated in the microorganisms was extracted and confirmed by thin-layer chromatography (TLC) and fast atom bombardment (FAB) mass spectrometry.  相似文献   
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