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91.
Noriaki Kamiya 《代数通讯》2013,41(6):1833-1844
It is the object of this paper to investigate the Peirce decomposition for Freudenthal-Kantor triple systems, by making use of the concept of anti-derivation of the triple systems. 相似文献
92.
Yoshio Kobayashi Takuya Nozawa Tomohiko Nakagawa Kohsuke Gonda Motohiro Takeda Noriaki Ohuchi Atsuo Kasuya 《Journal of Sol-Gel Science and Technology》2010,55(1):79-85
This paper describes a method for direct coating of fluorescent semiconductor nanoparticles with silica shell. The fluorescent
semiconductor nanoparticles used were CdSe
x
Te1–x
nanoparticles coated with ZnS and succeedingly surface-modified with carboxyl groups, or quantum dots (Q-dots). The Q-dots
were silica-coated by performing sol–gel reaction of tetraethyl orthosilicate (TEOS) using NaOH as a catalyst in the presence
of the Q-dots. Quasi-perfect Q-dots/silica core-shell particles were formed at 5.0 M H2O and 4.0 × 10−4 M NaOH. Under these concentrations of H2O and NaOH, the particle size of Q-dots/silica particles could be varied from 20.1 to 38.1 nm as the TEOS concentration increased
from 2.5 × 10−4 to 50 × 10−4 M. The Q-dots/silica particles showed fluorescence as well as the uncoated Q-dots. 相似文献
93.
Ayako Sekine Noriaki Seko Masao Tamada Yoshio Suzuki 《Radiation Physics and Chemistry》2010,79(1):16-21
A fibrous adsorbent for Hg ions was synthesized by radiation-induced emulsion graft polymerization of glycidyl methacrylate (GMA) onto a nonwoven cotton fabric and subsequent chemical modification. The optimal pre-irradiation dose for initiation of the graft polymerization of GMA, which minimized the effects of radiation damage on the mechanical strength of the nonwoven cotton fabric, was found to be 10 kGy. The GMA-grafted nonwoven cotton fabric was subsequently modified with ethylenediamine (EDA) or diethylenetriamine (DETA) to obtain a Hg adsorbent. The resulting amine-type adsorbents were evaluated for batch and continuous adsorption of Hg. In batch adsorption, the distribution coefficients of Hg reached 1.9×105 and 1.0×105 for EDA- and DETA-type adsorbents, respectively. A column packed with EDA-type adsorbent removed Hg from 1.8 ppm Hg solution at a space velocity of 100 h?1, which corresponds to 16,000 times the volume of the packed adsorbent. The adsorbed Hg on the EDA-type adsorbent could be completely eluted by 1 M HCl solution. A microbial oxidative degradation test revealed that the EDA-type adsorbent is biodegradable. 相似文献
94.
Deng W Onji T Yamaguchi H Ikeda N Harada A 《Chemical communications (Cambridge, England)》2006,(40):4212-4214
Photoinduced electron transfer between a porphyrin and a new guest cyclodextrin bearing viologen occurs by a supramolecular formation with conformational change of a guest molecule. 相似文献
95.
96.
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98.
Pinar?Akka??Kavakli Noriaki?Seko Masao?Tamada Olgun?GüvenEmail author 《Adsorption》2005,10(4):309-315
A new polymer containing double amidoxime groups per repeating unit was synthesized to enhance the metal ion uptake capacity. The adsorption properties of this new polymeric adsorbent, amidoximated poly(N,N-dipropionitrile acrylamide), for U(VI), V(V), Cu(II), Co(II) and Ni(II) ions were investigated by batch and flow-through processes at very low concentration levels (ppb). The chelating polymer showed high adsorption capacity for uranyl as well as vanadyl ions. In selectivity studies from a mixture of metal ions in aqueous solutions, the adsorbent showed high selectivity for uranyl and vanadyl ions in the following order: U(VI) > V(V) Co(II) = Cu(II) Ni(II) as determined by calculating the distribution coefficients D, of corresponding ions. The adsorption of uranyl and vanadyl ions from natural seawater by the new adsorbent was also examined in flow through mode. 相似文献
99.
Wakabayashi N Takeichi M Uchida H Watanabe M 《The journal of physical chemistry. B》2005,109(12):5836-5841
Oxygen reduction reaction (ORR) activity and H(2)O(2) formation at Pt(54)Fe(46), Pt(68)Co(32), and Pt(63)Ni(37) electrodes in 0.1 M HClO(4) solution at 20 to 90 degrees C were investigated by using a channel flow double electrode method. In the temperature range of 20-50 degrees C, the apparent rate constants k(app) for ORR at these electrodes were found to be 2.4-4.0 times larger than that at a pure Pt electrode, whereas their apparent activation energies of 41 kJ mol(-1) at -0.525 V vs E degrees (0.760 V vs RHE at 30 degrees C) were comparable to that at the Pt electrode. H(2)O(2) yield was ca. 1.0% at Pt(54)Fe(46) and ca. 0.16% at Pt(68)Co(32) and Pt(63)Ni(37) between 0.3 and 1.0 V vs RHE. The k(app) values at the alloy electrodes decreased with elevating temperature above 60 degrees C, and settled to almost the same values at the Pt electrode. The H(2)O(2) production was not detected at the alloy electrodes once heated at the high temperature in the solution, probably due to the thickening of the Pt skin-layer by a considerable dissolution of nonprecious metal components (Fe, Co, Ni) from the alloys. 相似文献
100.
Complex formation of α-cyclodextrin (α-CD) with decyltrimethylammonium (DeTAB), N,N-dioctyldimethylammonium (DOAB), and N,N-didecyldimethylammonium bromides (DDeAB) was investigated by proton NMR spectroscopy. Analysis of chemical shifts yielded macroscopic 1:1 and 1:2 binding constants (K1 and K2) and chemical shift differences (ΔδSD and ΔδSD2) for the 1:1 and 1:2 complexes of DeTAB, DOAB, and DDeAB with α-CD. The K1 and K2 values of DDeAB were quantitatively explained on the basis of the assumption that the microscopic 1:1 binding constant of DDeAB is identical to the observed K1 value of DeTAB. The K2 value of DDeAB was also explained in terms of its observed K1 value and the independent binding of two alkyl chains. Furthermore, the ΔδSD and ΔδSD2 values for protons of DDeAB and α-CD were quantitatively explained on the basis of the assumption that the geometry of the decyl group of DDeAB in an α-CD cavity is identical to that of DeTAB. The ΔδSD value was also explicable on the basis of the same geometric assumption and the observed ΔδSD2 value for this system. Similar results were obtained for the 1:1 and 1:2 DOAB-α-CD complexes. 相似文献