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341.
Yoshinobu Baba Mitsutomo Tsuhako Shigeru Enomoto A. Michael Chin Robert S. Dubrow 《Journal of separation science》1991,14(3):204-206
High resolution separations of nucleic acids have been performed using high performance capillary electrophoresis (HPCE) and high performance liquid chromatography (HPLC). Electropherograms showing HPCE separations of single and double stranded DNA are presented and compared with HPLC separations. Single base resolution of poly(dA) oligonucleotides in the size range of 12 to 60-mers was achieved in 35 min using HPCE. Plate numbers for HPCE are in the hundreds of thousands and reproducibility is about 1–2 % (RSD). In comparison with HPLC separations, the resolution of nucleic acids obtained using HPCE is much better than that using HPLC, while reproducibility of HPCE is comparable with that of HPLC. 相似文献
342.
In this paper we propose a measurement method that uses a laser diode (LD) attached to a flying slider and a semi-transparent rotating disk mirror for an extremely-short-external-cavity configuration. Not only the wavelength, but also the spectrum and the light output are measured at room temperature with the external cavity length, the reflectivities of the LD facets and the external mirror, and the drive current as parameters. We have confirmed wavelength variation as great as 30 nm by changing the external-cavity length for a 1.3-$mUm wavelength laser diode with an antireflection coating on the LD facet facing the external mirror. 相似文献
343.
344.
Yoshinobu Itoh 《Optics Communications》1973,8(4):387-389
An incoherent-to-coherent converter is constructed with a bismuth germanium oxide crystal. Several experiments are carried out with emphasis on the spatial resolution. It is found that the line width of the read-out image is approximately proportional to the logarithm of the write-in pulse duration, and that longer exposures cause the read-out image to deteriorate sooner. Several ways to increase the spatial resolution of the converter are discussed. 相似文献
345.
Host-guest complexes of calix[4]resorcarene with chiral molecules were efficiently formed by solid-solid grinding and exhibited CD Cotton effects reflecting the absolute configuration of the guest. 相似文献
346.
M. Fukushima N. Horikawa R. Kajikawa H. Kobayakawa K. Mori T. Nakanishi C.O. Pak S. Suzuki T. Matsuda N. Tokuda M. Daigo T. Ohshima 《Nuclear Physics B》1977,130(3):486-504
The polarized target asymmetry for the process γp → π+n has been measured for incident photon energies below 1.02 GeV over a range of c.m. angles from 40° to 160°. π+ mesons from a polarized butanol target were detected by a magnetic spectrometer. The results are compared with predictions given by existing analyses. A tentative interpretation of the data is performed, and a larger contribution of S-wave resonances is suggested. The photocouplings of dominant resonances were hardly changed by the inclusion of new data and they seem to be almost uniquely determined. 相似文献
347.
348.
349.
Takakazu Kojima Masahiko Hamada Masa-Aki Miyahara Yoshinobu Hosaka 《Journal of Polymer Science.Polymer Physics》1987,25(7):1481-1489
Studies on solute–solvent interactions of oligo(m-benzamide)s in N,N-dimethylacetamide (DMA) have been carried out. The enthalpies of solution have been measured for oligo(m-benzamide)s and oligo(m-phenylene)s in DMA and benzene. Contributions of enthalpies of cavitation and dispersion interaction to the enthalpy of transfer from benzene to DMA, ΔHtr (Ben → DMA), have been examined for oligo(m-phenylene)s. A considerable contribution of excess enthalpy, ΔHE (Ben → DMA), to ΔHtr (Ben → DMA) has been found, which increases with the number of benzene rings of the solute. By assuming that ΔHE (Ben → DMA) of diphenyl (DP) is equal to that of benzanilide (BA) in DMA, the amide hydrogen bond enthalpy of BA in DMA, ΔH estimated by “the pure base method” corrected for the enthalpies of cavitation and dispersion interaction. The ΔH value has been given by the following expression including the unknown solubility parameter of BA, δBA: The evaluation of δBA has resulted in the conclusion that ?ΔH is smaller than 10.9 kJ mol?1. Moreover, ΔHtr (TMU → DMA) for oligo(m-benzamide)s has been examined. It has been shown that the amide hydrogen bonding ability of DMA is lower than that of TMU. The linearity of the plot of ΔHtr (TMU → DMA) against the number of amide bonds in the molecule has been explained by the increase in hydrogen bond enthalpies with the number of amide bonds in the molecule. 相似文献
350.
Blazed ion-etched holographic gratings with a high absolute diffraction efficiency, good diffracted wavefront, high resolution, and low stray light have been produced. The performances were proved to be the same as, or superior to, commercially available blazed gratings produced by a ruling technique. 相似文献