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961.
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The asymmetry and fringe inclination of the sawtooth-like waveform observed in the self-mixing signal obtained from a semiconductor laser with optical feedback enable the direction discrimination of line-of-sight motion of external target surfaces. We investigated the effects of linewidth enhancement factor and feedback strength on the asymmetry and the direction of fringe inclination of the signal by numerical simulations. For the first time, we show that direction of the fringe inclination is determined not only by the direction of the target motion but also by the value of the linewidth enhancement factor. 相似文献
966.
Y. Yoshida T. Nakazawa H. Yoshikawa T. Nakanishi 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(3):541-545
A partition coefficient (λ) for Ra in gypsum was determined from coprecipitation experiment using oversaturation method. The λ-value derived for Ra was: λ
Ra = 0.32±0.15. Saturation state was estimated with the initial concentration of Ca and SO42− in an experiment of the present study. Saturation index was calculated to be (0.49±0.02). This value was similar to those
corresponds to analogous case where slow precipitation rate was kept in coprecipitation experiment for Sr in gypsum. Therefore,
derived λ-value is thought to describe partition of Ra and Ca in solid phase and solution under an equilibrium condition without the
effect of kinetic of precipitation. Determined λ-value was compared with those of other alkaline elements in sulfate minerals. The derived λ-value is smaller than that of Ra in barite and is similar to those of Sr in gypsum. This trend agrees with mechanical understanding
for the size effect against partition coefficient. 相似文献
967.
Inside Back Cover: New Insights into the Hexaphenylethane Riddle: Formation of an α,o‐Dimer (Angew. Chem. Int. Ed. 13/2015)
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968.
969.
Yoshihiro Kudo Ryo Fujihara Shoichi Katsuta Yasuyuki Takeda 《Analytical sciences》2007,23(8):1003-1006
The ion-pair formation constant (K(MLA)(0) in mol(-1) dm(3)) for Li(B15C5)(+) with a picrate ion (Pic(-)) in water was determined by potentiometry with a K(+)-selective electrode at 25 degrees C and an ionic strength of 0, where B15C5 denotes benzo-15-crown-5 ether. Using the concentration equilibrium constants, K(MLA), estimated from this value, the extraction constants (mol(-2) dm(6) unit) of about ten diluents were re-calculated from previously reported extraction data. Also, the distribution constants of an ion-pair complex, Li(B15C5)Pic, between water and the diluents were re-estimated. A disagreement in the determined K(MLA) value between a solvent-extraction method and potentiometry was explained in terms of the Scatchard-Hildebrand equation; it came from the fact that the hydration of Li(I) in Li(B15C5)Pic was larger than that of free B15C5 in water. Then, the previously determined value by the former method was re-estimated using the potentiometric K(MLA) value. 相似文献
970.
We developed a facile method of enzyme-mediated conversion of 6-tuliposide to α-methylene-γ-butyrolactone (tulipalin). We used a tuliposide-converting enzyme for the conversion of 6-tuliposides extracted from tulip tissues into the corresponding tulipalins in high yields within 2 h at pH 7.0. The resulting tulipalins were selectively extracted by using several organic solvents. 相似文献