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641.
642.
The Coriolis interactions between ν1 and ν3, and between ν2 and ν3 in SO2 have been analyzed to obtain the signs of the products ζ3.1c(a?Q3)(b?Q1) and ζ3.2c(a?Q3)(b?Q2). It has been found that both of the signs of these products are positive. Then, relative signs of (?Q1) have been determined using the calculated values of the Coriolis zeta constants for the present definition of the normal coordinates. The obtained sign combination of (?Qi) is ±(+?+), which agrees with the one predicted by the molecular orbital calculations. Using the sign combination (+?+), the polar tensors of S and O atoms were also calculated.  相似文献   
643.
Experiments were made to determine the dependence of the size of contact-free nanoparticles produced by aerosol process on gas pressure. The particles were collected as contact-free dispesoids in hexane with a cationic surfactant, and the geometric mean sizes were below 10 nm in diameter. It was found that the size increased linearly as the pressure was raised from 0.04 to 1.43 kPa for Ag, Bi, Cu, and Te. Similar slopes were obtained for the linear function between size and gas pressure except for Te.  相似文献   
644.
645.
We have observed the formation of C2-60 and C2-70 in collisions between C(-)(60)/C(-)(70) and Na atoms. Cross sections for the electron transfer to the monoanion are determined to be 36+/-9 and 57+/-14 A(2) for C-60 and C-70, respectively. A simple model investigation suggests that the electron is transferred from a Na atom to a low-lying electronic state of the fullerene to form a dianion. The method leads to pico-ampere energetic beams of C60 dianions that can be used for spectroscopy and lifetime studies.  相似文献   
646.
Kaya T  Numai D  Nagamine K  Aoyagi S  Shiku H  Matsue T 《The Analyst》2004,129(6):529-534
The metabolic activity of E. coli cells embedded in collagen gel microstructures in a cone-shaped well and in a cylindrical micropore was investigated using scanning electrochemical microscopy (SECM), based on the oxygen consumption rate and the conversion rate from ferrocyanide to ferricyanide. The analysis of the concentration profiles for oxygen and ferrocyanide afforded the oxygen consumption rate and the ferrocyanide production rate. A comparison indicated that the ferrocyanide production rates were larger than the oxygen consumption rate, and also that the rates observed in the cylindrical micropore were larger than those observed in the cone-shaped well. The ferrocyanide production rate of a single E. coli cell was calculated to be (5.4 +/- 2.6) x 10(-19) mol s(-1), using a cylindrical micropore system.  相似文献   
647.
Yoo S  Jung Y  Lee DS  Han WT  Oh K  Murakami Y  Edamura T  Maruyama S 《Optics letters》2005,30(23):3201-3203
Optical anistropy at optical communication wavelength was observed in films of vertically aligned single-walled carbon nanotubes (SWNTs). We report the control of both the polarization state and transmission of incoming light at 1550 nm by azimuthal and axial tilting of SWNT film about its aligned axis. The experiments reveal that the polarization state of light is susceptible to the azimuthal angle of the aligned direction of a SWNT having semiconductor characteristics and the intensity of the output beam after SWNT film shows cosine function dependence on the axial tilting angle.  相似文献   
648.
Ito S  Kimura S  Yoshifuji M 《Organic letters》2003,5(7):1111-1114
[reaction: see text] Sterically protected (Z)-1-(2,4,6-tri-tert-butylphenyl)-2,5-dibromo-1-phosphapent-1-ene was allowed to react with potassium tert-butoxide to afford a cyclopropylidenephosphaethene, which was characterized spectroscopically and by X-ray crystallography. Construction of the cycloalkyl groups and isomerization of 1-phosphapenta-1,2,4-trienes to cyclopropylidenephosphaethenes are also described.  相似文献   
649.
Enantioselective solubilization of DL-amino acids has been observed in various organic solvents containing copper(II) complexes of N-alkyl-L-proline, and the enantioselectivity appears to be caused by the formation of diastereomeric mixed-ligand complexes and differences in their stability.  相似文献   
650.
An antibiotic iturin A was separated into several components (A-1≈8) using HPLC and the structures of the β-amino acids of each component were established based on NMR and mass spectral analysis.  相似文献   
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