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991.
The enzyme AMP-deaminase was entrapped in an acrylamide-glycidylmethacrylate copolymer. No leakage of AMP-deaminase was observed from the copolymer. The optimum pH of native AMP-deaminase was 5.6. The pH was displaced to 5.0 with immobilization in the copolymer. The immobilized AMP-deaminase column maintained more than 95% of initial activity after 10 days of operation. 相似文献
992.
Isao Hasegawa 《Journal of Sol-Gel Science and Technology》1995,5(2):93-100
The reaction of the cubic octameric silicate anion, Si8O
20
8–
, with dimethyldichlorosilane in 2,2-dimethoxypropane yielded solid products. FT-IR and solid-state 29Si NMR spectra of the products indicate that the silicate anion becomes cross-linked via the dimethylsilyl group without degradation of the cubic core, resulting in the formation of organic/silica hybrids consisting of the Si8O
20
8–
structure as a building block. The hybrids are thermally stable up to ca. 380°C in air. The specific surface area of the hybrids is 31 m2 g–1, while the value increases to 339 m2 g–1 after calcination at 350°C in air. The process of increasing the surface area of the hybrids by the heat-treatment was investigated using solid-state 13C NMR spectroscopy. 相似文献
993.
Isao Kanesaka Tsuneyuki Miyajima Kiyoyasu Kawai 《Journal of Molecular Structure》1984,118(3-4):189-195
The IR intensity of ν1 of carbon disulfide is reported in various states. The intensity increases with a decrease in temperature. Less than 10% of the observed intensity can be explained in terms of an electric field applied from an adjacent molecule. On the other hand, nearly half of the intensity is explained in terms of a vibrational coupling of ν1 with ν3 or ν2, which is estimated from dimer models, on the assumption that the observed IR and Raman frequencies can be attributed to dimers. 相似文献
994.
Satoshi Fukuoka Hiroshi Kamishima Koji Sode Isao Karube 《Applied biochemistry and biotechnology》1990,26(3):239-248
Endo-pectate lyase (PATE) from Erwinia carotovora was selectively cosedimented with extracellularly produced lipopolysaccharide-lipid complex (LPSLC) through dialysis of the cell free culture broth. The selective isolation of PATE was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The cosedimentation of the PATE with LPSLC was initiated by decreasing conductivity of the solution and terminated at approx 1 m siemens (mScm-1). As much as 62% of PATE activity in the culture broth was removed by precipitation. PATE was isolated from the precipitate by gel chromatography. The cosedimentation of PATE with LPSLC was remarkably affected by pH or ionic strength. The addition of polycationic peptide polymyxin B sulfate or a metal chloride affected the interaction. The cosedimentation was diminished by acetylation of the free amino groups of PATE. From these results, it was confirmed that the cosedimentation was induced by electrostatic interaction. 相似文献
995.
996.
Scattering of potassium atomic beams from cleaved surfaces of LiF, KCl and mica were studied. The observed spatial distributions follow the cosine distribution in most cases. At large incident angles the distributions from LiF and KCl deviate from the cosine and show apparent backscatterings. A simple model is proposed to interpret the backscattering in terms of macroscopic roughness of cleaved surfaces. The sticking coefficient S (t) is defined and the mass balance between the incident and outgoing atoms is examined. Mass balance holds within the limits of errors on the surfaces of LiF and KCl at temperatures above 400 K. On a mica surface deposition of potassium atoms is observed even at temperatures higher than room temperature. It is shown from the change of the sticking coefficient that the deposition does not proceed linearly in the initial period. 相似文献
997.
998.
999.
1000.
A novel sesquiterpene lactone was isolated from the pericarps of Illicium anisatum, a well known toxic plant in Japan, and its structure was established from spectral data and X-ray crystallographic analysis. 相似文献