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51.
Alkaline-earth metals in human bone samples have been determined simultaneously by inductively-coupled plasma atomic-emission spectrometry (ICP-AES). Results obtained by atomic-absorption spectrometry for Mg, Sr and Ba, and complexometry for Ca, have been compared with those by ICP-AES for a laboratory-control bone sample. Accuracy and precision were examined by analysing the IAEA animal bone standard (H-5). Agreement with the certified values to within 5% was obtained. The concentrations of the elements in foetal bone have also been determined. 相似文献
52.
Nevin Çelebi Osamu Shirakura Yoshiharu Machida Tsuneji Nagai 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(4):407-413
Inclusion complex formation of piromidic acid (PA) with dimethyl--cyclodextrin (DM--CD) in aqueous solution and in the solid state was confirmed by the solubility method, differential scanning calorimetry (DSC) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The apparent stability constant,K
c
, of the complex was estimated to be 244 M–1. The stoichiometry of the complex was given as the ratio 1:2 of PA to DM--CD. The dissolution rate of the PA/DM--CD complex was much greater than that of intact PA.Presented at the Fourth International Symposium on Inclusion Phenomena and the Third International Symposium on Cyclodextrins, Lancaster, U.K., 20–25 July 1986. 相似文献
53.
Chowdhury Wasimul Q. Idehara Kenji Maeda Isamu Umeda Fusako Yagi Kiyohito Miura Yoshiharu Mizoguchi Tadashi 《Applied biochemistry and biotechnology》1996,57(1):361-366
Applied Biochemistry and Biotechnology - A marine photosynthetic bacterium,Rhodopseudomonas sp. strain W-1S, accumulated polyhydroxybutyrate (PHB) to 56% of the dry cell weight under microaerobic... 相似文献
54.
Yoshiharu Kagami Jian Ping Gong Yoshihito Osada 《Macromolecular rapid communications》1996,17(8):539-543
Shape memory polymers were prepared by copolymerizing stearyl acrylate and methyl acrylate. The principle of this shape memory effect is based on reversible order-disorder transition of crystalline aggregates of stearyl moieties. A specific feature of this type of shape memory copolymer is that the transition temperature at which the polymer abruptly becomes soft and deforms can be controlled by changing the monomer composition, which enables one to adjust the shape memory effect at a desired temperature. Mechanism and process of the shape memory behaviors were discussed. 相似文献
55.
Norio Manabe Kenichi Kawamura Masanao Ishikawa Shoutarou Suzuki Boping Liu Minoru Terano Hisayuki Nakatani 《Polymer Testing》2005,24(8):994-997
In this study, a novel potentiometric titration of hydroperoxide in degraded polypropylene (PP) is proposed. This titration is quite sensitive compared with the conventional ones such as UV and manual titrations, and its detection limit was about 2 meq/kg. The sensitivity was equal to that of molecular weight measurement by GPC for the degraded PP and, in addition, the volatilization behavior of the hydroperoxide could be detected. This titration was found to be very effective for the determination of PP degradation. 相似文献
56.
Oka H Ito Y Ikai Y Matsumoto H Kato K Yamamoto I Shimizu M Kawamura N Miyazaki Y Nojiri T Okumura M Ohmi S Sato T Mori G 《Journal of AOAC International》2001,84(2):350-353
A survey was conducted to determine the incidence of tetracycline antibiotic (TCAs) residues in the kidneys of slaughtered animals that did not pass inspection for human consumption by the Japanese Food Sanitation Law and the Meat Inspection Law at the slaughterhouses in Aichi Prefecture, Japan, from April 1985 to March 1998. The kidneys were analyzed by the AOAC Official Method 995.09. Among 424 animals (147 cattle and 277 pigs), 131 (30.9%) were contaminated with TCAs, including 69 (16.3%) with chlortetracycline (CTC), 61 (14.4%) with oxytetracycline (OTC), 3 (0.7%) with tetracycline (TC), and 1 (0.2%) with doxycycline (DC). One sample (cattle kidney) was contaminated with both OTC and DC. The frequencies of OTC and TC residues were significantly higher (p < 0.05) in cattle than in pigs, whereas, the frequency of CTC was significantly higher (p < 0.01) in pigs. Pig kidney samples collected in 1991-1997 had significantly higher incidences of TCAs and CTC (p < 0.01) residues than those in 1985-1986. 相似文献
57.
The combination of pivalic or acetic acid as a promoter and EtOAc as a solvent and acetyl donor proved to be efficient for the chemoselective N-acetylation of primary aliphatic amines to afford the corresponding acetamides. We developed a simple and convenient approach, which requires mild reaction conditions. Competitive inter- and intramolecular reactions between aliphatic amines, alcohols, and aromatic amines were examined, and chemoselectivity was achieved by adjusting the conditions of the reaction. 相似文献
58.
Masayuki Yoshikawa Yoshiharu Ikeda Hiroshi Kayakiri Kohei Takenaka Isao Kitagawa 《Tetrahedron letters》1982,23(45):4717-4720
By use of a decarboxylation reaction with lead tetraacetate and a deacetoxylation reaction with sodium borohydride as key-reactions, paromamine ( and tri-N-benzyloxycarbonylparomamine () were synthesized from D-glucosamine. 相似文献
59.
60.
Multi-layered thin films, which consisted of metallic silver, GeSe3 glass, and silver oxyhalide superionic conductor glass were prepared. Photo- and electrochemical reaction of metallic silver with the chalcogenide glass layer was studied by optical absorbance and cyclic-voltammetry. Photo-doping of silver through the superionic glass layer was observed using evaporated AgI---Ag2MoO4 film and it was partly undoped by electrochemical treatment. However, no photo-doping was observed for the cell consisting of a AgI---AgPO3 dip-coated layer. The doped silver was dissolved into the GeSe3 layer during the photo-doping process. However, it formed another intermediate compound layer (probably silver selenide) during the electrodoping process. 相似文献