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91.
A laser spectroscopic technique for studying fluctuations of structural objects is presented, together with some results of our investigations including an observation of forced vibration of a refrigerator, intrinsic vibrations of buildings, and appearance of a fluctuation in rotational speed due to fatigue. An alternative detection technique which uses the scattered light for monitoring in place of the mirror-reflected beam is also presented. A leak of water out of a pipeline was detected with this method. The results obtained with this laser spectroscopic technique should form a useful collection of data regarding fluctuation analysis of various objects. 相似文献
92.
1,3-Dimethyl- or 1,3-divinyl-1,3-di-t-butoxydisiloxane-1,3-diol and 1,3-diphenyldisiloxane-1,1,3,3-tetraol were synthesized by hydrolysis of the corresponding diisocyanatodisiloxanes and tetrachlorodisiloxane. The disiloxanediols were soluble in common organic solvents and thermally very stable, therefore, they could be sublimed without decomposition. X-ray crystallography showed that the disiloxane-1,3-diols in the crystal feature a 1.21 nm diameter columnar array with intermolecular hydrogen bonding. The disiloxane-1,1,3,3-tetraol, on the other hand, revealed molecules with a gauche- and anti-conformation depending on crystallization method which formed a columnar array and a sheet-like array, respectively. It was confirmed that these silanols can be potential building blocks for ladder oligosilsesquioxanes. 相似文献
93.
An edge of a k-connected graph is said to be k-contractible if the contraction of the edge results in a k-connected graph. A k-connected graph with no k-contractible edge is said to be contraction critically k-connected. We prove that a contraction critically 5-connected graph on n vertices has at least n/5 vertices of degree 5. We also show that, for a graph G and an integer k greater than 4, there exists a contraction critically k-connected graph which has G as its induced subgraph. 相似文献
94.
95.
R. Amano 《Journal of Radioanalytical and Nuclear Chemistry》1986,100(2):335-346
Radioactive implant induced X-ray emission (RIXE) spectrometry was examined by mixing a sample in solution with a radioisotope. The radioisotopes of57Co,67Ga,75Se,99mTc,111In,125I and201Tl were used as implant X-ray excitation sources. Copper, strontium, iodine, barium, lead and uranium solutions were used as samples to be analyzed. K X-ray for all samples and L X-rays for lead and uranium samples were measured with a pure Ge detector. The excitation characteristics of each radioisotope are discussed using the effective excitation efficiency (eff) defined by the equation eff=Nc/(NaNd), where Nc is the number of counts in the X-ray peaks, Na is the number of atoms of interest in the sample, and Nd is the total number of decays of radioisotope for the counting interval. 相似文献
96.
97.
Takayoshi Amano 《Journal of Molecular Spectroscopy》1981,88(1):194-206
The Stark effect of the 22 ← 21(E1), 21 ← 30(E1) microwave transitions in the ground state and the 22 ← 21(E1) microwave transition in the first excited CO stretching vibrational state are measured by means of infrared-microwave double resonance with the qQ1(2)E1 infrared transition as the pump transition in the range of 1000 to 2300 V/cm. The dipole moments μa and μb as well as the off-diagonal rotational constant Dab are determined for both the ground and the excited states. The frequency of the qQ1(2)E1 infrared transition is found to be lower by 128 ± 2 MHz than that of the P(34) CO2 laser. 相似文献
98.
99.
Such an asymmetric [2,3]-Wittig variant that is both highly enantio- and erythro-selective is described within the context of the chiral synthesis of the insect pheromones, (3, 4)-4-methyl-3-heptanol and ()-4-methyl-3-heptanone. 相似文献
100.
Takayoshi Amano 《Journal of Molecular Spectroscopy》1984,103(2):436-454
The fundamental vibration rotation bands of OH and OD have been observed with an estimated accuracy of 0.001 cm?1. Simultaneous fits of the infrared and microwave data are performed to improve the molecular constants in the v = 0 and v = 1 states. The correlated parameters γv and AD are determined by combining the data for OH and OD. Some discussion is presented on the correlated molecular parameters. 相似文献