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991.
Shigeki Nemoto Kojiro Suga Yuji Fukuda Masao Nomura Tatsuya Suzuki 《Journal of Nuclear Science and Technology》2013,50(4):425-437
Breakthrough mode liquid chromatography was employed to study calcium isotope fractionation. Highly porous silica beads, the inner pores of which were embedded with a benzo-18-crown-6 ether resin or a benzo-15-crown-5 ether resin, were used as column packing material. For both the resins, enrichment of heavier isotopes of calcium was observed in the frontal part of their respective calcium chromatograms. The values of the isotope fractionation coefficient were on the order of 10?3 and 10?4 for the benzo-18-crown-6 ether and benzo-15-crown-5 ether resins, respectively. The observed isotope fractionation coefficient was dependent on the concentration of hydrochloric acid in the calcium feed solution; a higher hydrochloric acid concentration resulted in a smaller fractionation coefficient value. The present calcium isotope effects were most probably mass dependent, indicating they came from isotope effects based on molecular vibration. Molecular orbital calculations supported the present experimental results in a qualitative fashion. 相似文献
992.
Cheol Ho Pyeon Masao Yamanaka Akito Oizumi Masahiro Fukushima Kazufumi Tsujimoto 《Journal of Nuclear Science and Technology》2013,50(11):1324-1335
Sample reactivity worth experiments are carried out by substituting aluminum (Al) plates for bismuth (Bi) ones at the Kyoto University Critical Assembly. At the beginning, uncertainty quantification of bismuth isotope is conducted by deterministic calculations with nuclear data library JENDL-4.0, with the use of experimental results of sample reactivity worth. Then, with the combined use of current (Bi) and previous (Pb) experimental results that demonstrate the comparative difference in the sensitivity and uncertainty of Bi and Pb isotopes, experimental results of cross-section uncertainties of Bi isotope are available for examination of neutron characteristics of Pb–Bi coolant material in the accelerator-driven system. From the experimental analyses, further uncertainty analyses by neutron transport calculations are needed for several reactions of Bi isotope, especially with the use of the covariance data of capture, elastic scattering and inelastic scattering reactions in another nuclear data library. 相似文献
993.
Jun Oshitani Soichiro Kajimoto Mikio Yoshida George V. Franks Yasuo Kubo Shingo Nakatsukasa 《Advanced Powder Technology》2013,24(2):468-472
A continuous separator based on float–sink density separation using a gas–solid fluidized bed dense medium was used to upgrade iron ore. The separator has three devices for (A) conveying floaters, (B) recovering floaters, and (C) conveying and recovering sinkers. The optimum speeds of these devices were investigated using density adjusted spheres of the diameter = 30 mm in the range of 2400–3300 kg/m3 in density increments of 100 kg/m3. A mixture of zircon sand and iron powder was used as the fluidized medium to adjust the fluidized bed density to produce a separation density = 2850 kg/m3, a typical separation density for lump iron ore wet separation. The recovery of the spheres as floaters or sinkers depended on the speed of the devices, because the recovery was affected by the number density of spheres directly under the feeder, the local fluidized bed density, and flow currents in the medium derived from the movement of the devices. The optimum speeds were determined to be 3.5 cm/s for (A), 2.0 rpm for (B) and 1.0 cm/s for (C), respectively. Continuous separation experiments were conducted on lump iron ore particles in the size range of +11.1–31.5 mm in the fluidized bed with medium density of 2850 kg/m3 and feed rate of 200 kg/h. Comparison of the feed rate and the recovery rate indicated that the feed and the recovery were in equilibrium after 10 min of operation. The experiments resulted in nearly perfect separation; 98.4% of the ore with density greater than 2850 kg/m3 was recovered. The Fe, Al and Si content of the feed ore particles (before the separation) and the floaters and sinkers (after the separation) was measured using inductively coupled plasma spectrometry. The separator produced an upgrade in iron content of 3.3 wt% and reduced the Al and Si content by 44%. 相似文献
994.
Jian‐Nan Ma Su‐Le Wang Ke Zhang Zhi‐Gang Wu Masao Hattori Gui‐Lin Chen Chao‐Mei Ma 《Journal of food science》2012,77(10):C1097-C1102
Abstract: The apple‐shaped pear, the fruit of the Pyrus pyrifolia cv. pingguoli (Rosaceae) tree, is one of the most popular fruits in the northern part of China. The current study is the 1st report of its bioactive components. We identified 10 metabolites from the peels (exocarp) of apple‐shaped pear and assessed their toxicity. We then compared the anti‐oxidant activity, amount of total phenolic compounds, and total condensed tannin content of the peels and flesh (mesocarp) of apple‐shaped pear. The 6 major components in the peels and flesh of this fruit were quantified with Ultra Performance Liquid Chromatography–Electrospray Ionization Mass Spectrometry. Results revealed that the peels possessed stronger anti‐oxidant activity and contained larger amounts of phenolic compounds than the flesh. These results provide insights into the potential health benefits of this fruit and support the use of the fruit peels and products containing peels or peel components. Practical Application: The present research provided evidences that the pulp and peel waste from the juice industry of apple‐shaped pear may be a source of useful compounds. 相似文献
995.
Kubo K Hayakawa A Sakurai T Igarashi T Matsumoto T Takahashi H Takechi H 《Journal of oleo science》2010,59(12):661-666
The crystal structure of the photoinduced electron transfer (PET) fluoroionophore (3) was clarified by X-ray crystallographic analysis. A molecule 3 sits on a center of symmetry such that two anthracene ring systems are in an anti conformation with respect to one another across the piperazine ring. Intermolecular C-H···π and π···π interactions are observed. It was found that 3 was displayed unique photophysical properties in the presence of guest cations. Complexation of 3 with Zn2+ and NH?+ increased the fluorescence intensities of the host by a factor of 20. 相似文献
996.
Hiroaki Yamamoto Masao Morishita Takeo Yamamoto Kazuma Furukawa 《Metallurgical and Materials Transactions B》2011,42(1):114-120
The standard Gibbs energies of formation of Mo2B, ??MoB, Mo2B5, and MoB4 in the molybdenum-boron binary system were determined by measuring electromotive forces of galvanic cells using an Y2O3-stabilized ZrO2 solid oxide electrolyte. The results are as follows: $$ \begin{aligned} \Updelta_{\text{f}} {\text{G}}^\circ \left( {{\text{Mo}}_{2} {\text{B}}} \right)/{\text{J}}\,{\text{mol}}^{ - 1} & = - 193100 + 44.10T \pm 700\left( {1198{\text{ K to }}1323{\text{ K}}\left( {925^\circ {\text{C to }}1050^\circ {\text{C}}} \right)} \right) \\ \Updelta_{\text{f}} {\text{G}}^\circ (\alpha {\text{MoB}})/{\text{J}}\,{\text{mol}}^{ - 1} & = - 164000 + 26.45T \pm 700\left( {1213{\text{ K to }}1328{\text{ K}}\left( {940^\circ {\text{C to }}1055^\circ {\text{C}}} \right)} \right) \\ \Updelta_{\text{f}} {\text{G}}^\circ \left( {{\text{Mo}}_{2} {\text{B}}_{5} } \right)/{\text{J}}\,{\text{mol}}^{ - 1} & = - 622500 + 117.0T \pm 3000\left( {1205{\text{ K to }}1294{\text{ K}}\left( {932^\circ {\text{C to }}1021^\circ {\text{C}}} \right)} \right) \\ \Updelta_{\text{f}} {\text{G}}^\circ \left( {{\text{MoB}}_{4} } \right)/{\text{J}}\,{\text{mol}}^{ - 1} & = - 387300 + 93.53T \pm 3000\left( {959{\text{ K to }}1153{\text{ K}}\left( {686^\circ {\text{C to }}880^\circ {\text{C}}} \right)} \right) \\ \end{aligned} $$ where the standard pressure is 1 bar (100 kPa). 相似文献
997.
The surfactant effect of Ag on the thin film structure of TiO2 by radio frequency magnetron sputtering has been investigated. Comparisons between the atomic force microscopy images revealed that the surface roughness of TiO2 film mediated by Ag was smaller than that of the TiO2 film without Ag. The surface segregation effect of Ag was confirmed using X-ray photoelectron spectroscopy. The results of X-ray diffraction revealed that the initial deposition of a 0.4 nm thick Ag surfactant layer onto a Fe buffer layer prior to the deposition of the TiO2 film reduced the rutile (110) growth and enhanced the anatase (100) growth. It was concluded that Ag was an effective surfactant for changing the thin film structure of TiO2 on the Fe buffer layer. The photocatalytic effect of the fabricated TiO2 film was also investigated using the remote oxidation process. TiO2 films with the Ag surfactant exhibited higher photocatalytic activity than conventionally deposited TiO2 films. 相似文献
998.
Inoue Y Yoshida H Inoue K Shiozaki Y Kubo H Fujii A Ozaki M 《Advanced materials (Deerfield Beach, Fla.)》2011,23(46):5498-5501
Continuous tuning of lasing wavelength is achieved in cholesteric liquid crystal lasers by embedding a network of nanopores with an average size of 10 nm filled with liquid crystals inside a polymerized matrix with helical order. The device possesses both high transparency and a fast response time because the tuning is driven by local reorientation of the liquid crystal molecules in the nanopores. 相似文献
999.
1000.
Flavan-3-ol contents,anti-oxidative and α-glucosidase inhibitory activities of Cynomorium songaricum
Flavan-3-ol oligomers from the stems of Cynomorium songaricum were found to show potent SOD-like activity with one of the dimers being most potent. The flavan-3-ols also showed inhibitory activity on α-glucosidase, implying the beneficial effects of this herb on diabetes patients. The total (extractable and non-extractable) tannin content of this herb was found to be as high as 18.3%. The contents of catechin, flavan-3-ol oligomers and extractable tannins using 70% acetone, methanol or water were analysed. It was found that 70% acetone was the most efficient extract solvent amongst these three solvents, especially for higher flavan-3-ol oligomers. 相似文献