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81.
An improved method of sample injection was demonstrated for introducing ultra-low volume liquid on a microfabricated device. In our previous study, a pressure-driven injection method has been introduced and was applied to on-chip electrophoresis. In this study, the need for control of the air vent, which was indispensable for sample injection in the previous study, was completely eliminated, facilitating sample injection with great simplicity and high accuracy. This was realized by altering the topology of the air vent channel, which is connected to a hydrophobic and narrow channel (called a passive valve). Several types of air vent channels were designed and their injection performances were tested. In addition, by modifying the shape and the position of air vent channel and passive valve, the residual liquid volume inside the passive valve after sample injection was decreased to approximately 0.5% of the injected volume, a value which showed high reproducibility. 相似文献
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Koji Ishida Yoshiaki Uchida Shuji Ninomiya Masumi Osawa 《Fresenius' Journal of Analytical Chemistry》1990,336(5):419-422
Summary The thin-layer chromatographic behaviour of all the rare earths except Pm on silica gel in aqueous solutions of five alkali metal chlorides has been surveyed. The Rf-values and the logarithms of the separation factors relative to Gd vary in a regular and peculiar way with increasing atomic number, through a reflection of the strong tetrad effect. A discussion concerning the effects on the Rf-values of the solvent cations and the solvent anions, and typical chromatograms for the separations of multi-component mixtures containing adjacent lanthanoids are also presented. 相似文献
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Masumi Sato 《等离子体物理论文集》1973,13(1):9-25
Evolution from the linear growth to the nonlinearly saturated state of ionization waves (moving striations) is investigated from a viewpoint of an instability which appears in a plasma. The experiments were performed observing backward waves excited below the upper critical current Ic in xenon, argon, and argon-mercury gases at pressures of the order of Torr. It is found that (1) the behavior of the evolution obeys the Landau amplitude equation; (2) the saturated amplitude does not depend on an initial value, but only on plasma parameters; (3) the linear growth and squared saturation level are proportional to the excess over Ic, and when frequency-controlled, they have a parabolic dependence on the frequency; and (4) nonuniform axial changes in the dc state due to the nonlinear effects appear in a form of enhanced ionization in the plasma where the electron temperature and density are increased. The way of these behavior can be applied to a large number of spatially or temporally unstable modes. 相似文献
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Marisa Scrocco 《Journal of Electron Spectroscopy and Related Phenomena》1980,19(3):311-319
The satellite structure in the X-ray photoelectron spectra of nickel halides has been measured. The satellites found in the photoelectron spectra of Ni2+ 3p and 2p subshells have two common sources: multiples splitting and multi-electron excitations. The experimental spectra are compared with theoretical results on multiples splitting and with calculations of band structure. 相似文献