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61.
Dilute aqueous solutions of dodecyl-benzenesulfonic acid sodium salt (DBS-Na) and polyoxyethylenenonylphenyl ethers (PONPEs) were ultrasonically atomized. The surfactants were concentrated in collected mist droplets. The enrichment ratio increased with decreasing surfactant concentration. Depending on the surfactant’s molecular weight and affinity to water, different enrichment ratio was observed in the range of low feed concentrations. For anionic surfactant, DBS-Na, the enrichment ratio was significantly improved by KCl addition and a peak appeared on the plot of the ratio against KCl concentration. Addition of NaCl or CaCl2 · 2H2O to the surfactant solution also enhanced the enrichment ratio; however, the effect was relatively small. Such behaviors of the ratio were interpreted as enhanced interfacial adsorption of the surfactant and a lack of supply of surfactant monomers from liquid bulk because of slow breaking of surfactant micelles. Time required for collecting an amount of mist was also observed. Among the three salt systems, the time for KCl system was twice as long as others. This fact suggested that the formation of smaller droplets in KCl system. 相似文献
62.
Haitao Yang Tomoyuki Ogawa Daiji Hasegawa C.N. Chinnasamy Migaku Takahashi 《Journal of magnetism and magnetic materials》2006
Monodisperse bimetallic Pd–Co nanoparticles were prepared via a thermal decomposition of cobalt carbonyl using palladium seeds at the Pd/Co molar ratios 0.5%, 1%, and 5%. The heterogeneously nucleated nanoparticles without any size-selective precipitation are sufficiently uniform to self-assemble into ordered arrays. The as-synthesized nanoparticles are each a single crystal with a complex cubic structure called ε-Co. The presence of Pd seeds seems to improve the stability of Co nanoparticles against oxidation based on the results from time-dependent magnetization measurement. 相似文献
63.
T. Kawabata T. Adachi M. Fujiwara K. Hatanaka Y. Ishiguro M. Itoh Y. Maeda H. Matsubara H. Miyasako Y. Nozawa T. Saito S. Sakaguchi Y. Sasamoto Y. Shimizu T. Takahashi A. Tamii S. Terashima H. Tokieda N. Tomida T. Uesaka M. Uchida Y. Yasuda N. Yokota H. P. Yoshida J. Zenihiro 《Few-Body Systems》2013,54(1-4):93-97
The alpha inelastic scattering from 24Mg was measured to obtain the isoscalar natural-parity excitation strengths and to search for the α-condensed states. The multipole decomposition analysis for the measured cross sections was performed. The strength distributions for the ${{\Delta}L=0{-}3}$ were successfully obtained and the possible candidates for the α-condensed states around the 16O core were found. 相似文献
64.
65.
M. Hasegawa Y. Saitoh S. Yamaguchi H. Takahashi S. Ohnuki 《Hyperfine Interactions》1994,84(1):389-396
Angular correlation of two-photon annihilation radiation (ACAR) measurements have been performed to study the effect of interstitial impurities (O, C and D) on positronium (Ps) formation in irradiation-induced voids of vanadium. It has been observed that Ps formation is sensitively affected by doping with the interstitial impurities, irradiation dose, irradiation temperature, and also by post-irradiation annealing. The Ps component intensity is found to be related to segregation of the interstitial impurities and provides a new experimental method to study void surfaces. 相似文献
66.
The adsorption behavior of iodine on zeolites and silver-loaded zeolites has been studied by127I Mössbauer spectroscopy. Iodine is adsorbed on zeolites in two forms. One is a physically adsorbed species and the other is a dissociative species. The former is the major form and their intermolecular interactions are suggested to be weakened. Iodine is converted to silver iodide on the surface of silver-loaded zeolites, although some portion is physically adsorbed. 相似文献
67.
K. Yoshimura M. Takigawa Y. Takahashi H. Yasuoka M. Mekata Y. Nakamura 《Journal of magnetism and magnetic materials》1987,70(1-3):11-13
The nuclear spin-lattice relaxation rate, 1/T1, has been measured in weak itinerant ferromagnets Y(Co1−xAlx)2. The temperature and magnetic field dependence of 1/T1T has been found to be well described by the self-consistent renormalization (SCR) theory of spin fluctuations. The parameters characterizing spin fluctuations in this system were estimated from NMR and magnetic measurements. The temperature dependence of susceptibility calculated from these parameters well reproduces the experimental results. 相似文献
68.
Tomohiro Suetsuna Seiichi SuenagaShinya Sakurada Koichi HaradaMaki Tomimatsu Toshihide Takahashi 《Journal of magnetism and magnetic materials》2011,323(13):1793-1798
Self-forming core/shell nanoparticles of magnetic metal/oxide with crystalline grain size of less than 40 nm were synthesized. The nanoparticles were highly concentrated in an insulating matrix to fabricate a nanocomposite, whose magnetic properties were investigated. The crystalline grain size of the nanoparticles strongly influenced the magnetic anisotropy field, magnetic coercivity, relative permeability, and loss factor (tan δ=μ″/μ′) at high frequency. The packing ratio of the magnetic metallic phase in the nanocomposite also influenced those properties. High permeability with low tan δ of less than 1.5% at up to 1 GHz was obtained in the case of the nanoparticles with crystalline grain size of around 15 nm with large packing ratio of the nanoparticles. 相似文献
69.
Masai H Fujiwara T Matsumoto S Takahashi Y Iwasaki K Tokuda Y Yoko T 《Optics letters》2011,36(15):2868-2870
The authors have demonstrated white light emission of rare earth (RE)-free Mn-doped SnO-ZnO-P(2)O(5) glass. The RE-free glass shows white light emission with a high value of quantum efficiency (QE) comparable to conventional crystalline phosphor. It is notable that the high QE value is attained for RE-free transparent glass, and the broad emission can be continuously tuned by both the amount of activator and the composition of the glass. Since this glass possesses low-melting property, we emphasize that the glass phosphor will lead to the development of a novel inorganic white-light-emitting device in combination with a solid state UV light-emitting source. 相似文献
70.