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41.
42.
We present a fitting method for obtaining a functional form of the refractive index profile of planar microlenses made by ion exchange techniques from total shearing interferometric measurements. Compared to the usual power series expansion fit, this method allows a reduction in the number of coefficients needed to characterize a lens. 相似文献
43.
2-Mercaptobenzothiazole (MBT) loaded on glass beads with the aid of collodion was prepared and used for selective preconcentration of μg l?1 levels of copper(II) and lead from aqueous solutions. Copper and lead were quantitatively retained on the loaded beads from solutions of pH 5.0–6.0 and >5.0, respectively, while cadmium(II) and zinc(II) were retained at ? pH 6.0 and 7.0, respectively. The retention capacity of the loaded beads was ca. 108 μg Cu g?1 (1.7 μmol g?1) at pH 5.5 for beads of 0.3–0.4 mm diameter. The mole ratios of MBT to copper(II) and lead(II) were ca. 10 and 45, respectively, regardless of the amount of MBT loaded on the beads. Copper was completely retained on the column at a high flow rate (21.7 ml min? cm?2) and lead(II) at up to 12.7 ml min? cm?2. Cadmium(II) and zinc(II) were not retained quantitatively even at low flow rates (< 1.2 ml min?1 cm?2). Thus, selective preconcentration of copper and lead was achieved by passing the sample through the column at high flow rate at pH 6.5. The copper and lead retained on the column were complete eluted together with the collodion with 5 ml of MIBK by batch-mode elution, and determined directly by one-drop atomic absorption spectrometry. Copper(II) and lead(II) in several kinds of water were determined. 相似文献
44.
45.
Naohiro Murayama Takao Oikawa Takayuki Katto Ken'ichi Nakamura 《Journal of Polymer Science.Polymer Physics》1975,13(5):1033-1047
The piezoelectricity of PVDF thermoelect rets formed with vacuum-coated aluminum electrodes has been investigated in detail. The piezoelectricity depends on the β-form crystal structure of PVDF homopolymer and copolymers. However, the piezoelectricity is not attributed to the stress dependence of the spontaneous polarization of β-form crystals, but rather to the persistent polarization arising from trapped charges. The trapping mechanism is discussed. 相似文献
46.
Kikuo Oikawa 《应用有机金属化学》1988,2(4):391-393
This paper reviews the use of arsenic compounds in semiconductor manufacture and emphasizes the role of alkylated arsenic compounds. 相似文献
47.
Yuji Oikawa Tatsuyoshi Tanaka Kiyoshi Horita Tadao Yoshioka Osamu Yonemitsu 《Tetrahedron letters》1984,25(47):5393-5396
The DMPM (3,4-dimethoxybenzyl) protection for hydroxy function was deprotected more readily than the MPM (p-methoxybenzyl) protection by DDQ oxidation under neutral conditions, and applied to the synthesis of some synthons to macrolide and polyether antibiotics. 相似文献
48.
Synthetic routes for the branching pentasaccharides 4 and 5 of glycoproteins are described in a regio- and stereo- controlled way. 相似文献
49.
Nickel(II) complexes of N3O2 donor macrocycles incorporating 17- to 19-membered macrocyclic rings have been prepared. Physical measurements ind 相似文献
50.
The three-molecular cluster integrals for oxygen, nitrogen, and carbon tetrafluoride and the coefficients of viscosity and self-diffusion for nitrogen and carbon dioxide are discussed on the basis of the Kihara convex-core potential of intermolecular forces. For the equilibrium property, the relative size of the core is essential; for the transport properties, the nonspherical character of the molecule plays an important role. 相似文献