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971.
972.
A highly sensitive and selective method based on alkaline digestion for the simultaneous determination of bisphenol A (BPA) and 4-nonylphenol (NP) was developed. The method consists of digestion of the matrix with ethanolic KOH, extraction with diethyl ether under a mild alkaline condition, cleaning with successive aminopropyl (NH2) cartridges and derivatization followed by a GC-MS analysis. The assay accuracies, expressed as recoveries, were 82 - 113% for BPA and 89 - 97% for NP. The limits of detection of BPA and NP were 0.09 ng/g and 0.50 ng/g, respectively. The procedure will be reliable for the trace analysis of BPA and NP in human milk, since alkaline digestion can diminish their documented association with protein. 相似文献
973.
Hiroshi Hatano Tadafumi Sakata Kazuyuki Ogura Takayuki Hoshino Hiroaki Ueda 《Optical Review》2002,9(2):66-69
We proposed and developed a new solid immersion mirror (SIM) for near-field optical data storage. The SIM has some advantages, especially in manufacturing, because its shape is similar to a general plano-convex lens. Making an aperture of about 130 nm in diameter just on the focus area of the SIM, a bit-data recording onto a photochromic thin film was carried out. Minimum diameter of the written marks was estimated to be 180nm. We also demonstrated readout experiments where a recorded medium was rotating and a gap between the SIM and the disk was controlled with capacitance sensing. This is the first result of reading with a rotating disk using an SIM containing a small aperture.This paper was originally presented at the 10th Optical Near Field Workshop, which was held on June 27-28, 2001 at Osaka University, organized by the Optical Near Field Group, the Optical Society of Japan, an affiliate of the Japan Society of Applied Physics. 相似文献
974.
975.
976.
Fundamental properties of polymethyl acrylate solutions were examined: the reasonable Houwink-Mark-Sakurada relations and the theta temperature (θ) were determined to be 5 °C in toluene. Further, the measurements of intrinsic viscosity for polymethyl acrylate solutions as a function of temperature yielded a thermal transition due to a conformation change at 56 ± 1 °C, irrespective of molecular weight and solvent. An application of the two-parameter theory to such a transition gave a stepwise change of the short-range interaction: K×102=9.5 below 50 °C and 10.3 above 60 °C. This conformation transition is explained on the basis of the steric hindrance of the planar substituent to the main chain above 60 °C. 相似文献
977.
Naoya Yoshida Yuu Abe Hiroaki Shigeta Kazuyuki Takami Hisashi Osaki Toshiya Watanabe Kazuhito Hashimoto Akira Nakajima 《Journal of Sol-Gel Science and Technology》2004,31(1-3):195-199
Transparent hydrophobic polymer coating was prepared from methacrylate copolymer with molecular modeling in order to improve hydrophobicity and durability. Organic-inorganic hybridization improved the durability of the thin films. Furthermore the control of hydrophobicity and water droplet sliding properties of the flat coating was successfully performed. Water droplet sliding angle depended on the chemical structure of the materials, not on the hydrophobicity, while sliding motion simply depended on the hydrophobicity. 相似文献
978.
Yi Can Zhang Hiroaki Tagawa Shukuji Asakura Junichiro Mizusaki Hidekazu Narita 《Solid State Ionics》1997,100(3-4):275-281
A solid-state electrochemical cell of the type O2(air), PtLa0.9Sr0.1MnO3/Li2CO3(+5 mol% Li3PO4 + 6 mol% Al2O3)/Au, CO2, O2 was composed to determine CO2 concentration, where Li2CO3, a lithium ion conductor, was used as an electrolyte, and the perovskite-type oxide (La0.9Sr0.1MnO3)/O2-electrode as a reference electrode. The electromotive force (EMF) of the cell was found to be proportional to the logarithm of CO/2 partial pressure in CO2/O2/N2 gas mixtures at temperatures between 300 and 400 °C. The EMF responded to changes of CO2 partial pressure within 1 min at 400 °C. The sensitivity to CO2 of this cell was not affected by coexistence of O2, and the EMF remained constant after the first 15 days. The mechanism for sensing CO2 is discussed. 相似文献
979.