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141.
Takashi Hayashita Hiroaki Noguchi Hisashi Oka Manabu Igawa Makoto Takagi 《应用聚合物科学杂志》1990,39(3):561-569
The sorption behavior of heavy metal thiocyanate complexes was investigated for dibenzo-18-crown-6 (DB18C6) resin and bis[2-(o-methoxyphenoxy)ethyl]ether (BMPE) resin. The DB18C6 resin showed a high sorption ability and the degree of zinc sorption increased significantly with thiocyanate concentration. This behavior was not observed for BMPE resin. The sorption behavior was influenced by the countercation species, and the degree of sorption of zinc ions showed the maximum when the potassium thiocyanate was used as a complexing salt. The sorbed species appear to be KZn(SCN)3, K2Zn(SCN)4 in the potassium thiocyanate system, and Zn(SCN)2 in the lithium thiocyanate system, respectively, according to analysis of the sorption equilibrium. Sodium and ammonium thiocyanate systems show an intermediate behavior of the two. The sorption selectivity for DB18C6 resin depended not only on the hydrophobic nature of heavy metal thiocyanate complexes but also on the stabilization of counter cation species with crown ether matrix, and the sorption selectively was found to be effectively controlled by countercation species according to the cation-chelation mechanism. 相似文献
142.
143.
A relationship between emission characteristics of Ba atom as an emitter material and temperature distributions of an electrode in a fluorescent lamp is described, which is measured by using laser-induced fluorescence and black-body radiation method, respectively. In a virgin lamp, a hot spot observed at the electrode edge connected to the power supply is the main source of Ba atom emission. In a long-term-used lamp, it is shown that Ba atom emission, thermionic electron emission in cathode half-cycle and electron collection in anode half-cycle are most active on the hot spot appearing on the center of the electrode. 相似文献
144.
Sachiro Kakinoki Makoto Kitamura Mitsuhiro Yuge Masakazu Furuta Masahito Oka Yoshiaki Hirano Kenji Kono Isao Kaetsu 《Polymer Bulletin》2007,58(2):393-400
Summary Poly(proline) and random copolypeptide composed of Pro and Ala residues were synthesized, and their solution properties and
molecular conformation were investigated. Aqueous solutions of the polypeptide were irradiated with γ-rays above the transition
temperature. It was shown that the transition temperature of the aqueous solution of the copolypeptide is influenced by Ala-residue
content and γ-ray irradiation. 相似文献
145.
New catalytic technologies in Japan 总被引:9,自引:0,他引:9
Recent trends in R&D of catalytic technology in Japan (cleaner and more efficient production, environmental catalysts, and recycling processes) are overviewed and examples of recent achievements are listed. Examples are then described as zeolite-catalyzed organic reactions recently commercialized and expected to be commercialized: hydration of cyclohexene, synthesis of pyridine derivatives and gas-phase Beckmann rearrangement of cyclohexanone oxime. Finally, as an example of environmental catalysts, the NOx storage–reduction type three-way automobile catalyst, is introduced. 相似文献
146.
Used a technique for assessing the relative impact of facial–gestural expressions, as opposed to contextual information regarding the elicitor and situation, on the judgment of emotion. In Study 1, 28 undergraduates rated videotapes of spontaneous facial–gestural expressions and separately rated the emotionally loaded color slides that elicited those expressions. The source clarities of the expressions and slides were matched using correlation and distance measures, and 18 expressions and 9 slides were selected. In Study 2, 72 undergraduate receivers were shown systematic pairings of these expressions and slides and rated the emotional state of the expresser, who was supposedly watching that slide under public or private situational conditions. Expressions were found to be more important sources for all emotion judgments. For female receivers slides were relatively more important in the public than the private situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
147.
XPS (X-ray photoemission spectroscopy) and IR (infrared) analyses of poly(3-methylthienylene) films, electrochemically or chemically redoped0 with various chemical species at varying doping levels, have been investigated. On the basis of these results, the major chemical species of dopants have been identified. As a results, the dopant content was determined and the poly(3-methylthienylene) films were classified as light or heavy by doping level. The conductivity ranged from about 10?12 to 102 S cm?1 for all the films investigated. The conductivity and the activation energy of conduction for the heavily-doped films vary as a function of the dopant content, independent of the different chemical species of dopants. In particular, a sudden change is observed in the dependence of activation energy on dopant content. This sudden change may be associated with the semi-conductor-metal transition. Furthermore, it is shown that the specific absorption bands in the infrared are induced by the doping, intensified with increasing dopant uptake and accompanied by an increase in conductivity. 相似文献
148.
Makoto Sonehara Kazuaki Furihata Jun Koguchi Shingo Tanaka Toshiro Sato 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(Z1):S3-S8
In order to increase the Q‐factor of an RF spiral inductor used in the RF front‐end circuit of smartphone handsets, we introduced a carbonyl‐iron/epoxy composite magnetic core in the air‐core spiral inductor. The composite magnetic core, which was made by metal‐mask printing, consisted of carbonyl‐iron powder of 1.1 μm mean diameter and an epoxy resin matrix. We found that the 45 vol.% CIP composite magnetic core had a saturation magnetization of 0.9 T, relative permeability of ∼6, and loss tangent (tan δ) of ∼0.2 at 1 GHz. A two‐turn copper spiral inductor fabricated with the composite magnetic core filled only in the spacing between the conductor lines showed a clear Q‐factor increase of ∼29% compared to the air‐core spiral inductor at 1 GHz. Thus we obtained a substantial increase in the Q‐factor by the embedded composite magnetic core in the spacing between the conductor lines. The main reason for this is that the magnetic flux passing through the conductor lines was decreased by the magnetic core embedded in the spacing between conductor lines as a result of the magnetic flux passing mainly through the embedded magnetic core. Therefore, proximity effect is suppressed in the conductor line of the spiral coil. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
149.
150.
Dr. Naoki Umezawa Yuhei Horai Dr. Yuki Imamura Makoto Kawakubo Mariko Nakahira Dr. Nobuki Kato Akira Muramatsu Prof. Dr. Yuko Yoshikawa Prof. Dr. Kenichi Yoshikawa Prof. Dr. Tsunehiko Higuchi 《Chembiochem : a European journal of chemical biology》2015,16(12):1811-1819
A versatile solid‐phase approach based on peptide chemistry was used to construct four classes of structurally diverse polyamines with modified backbones: linear, partially constrained, branched, and cyclic. Their effects on DNA duplex stability and structure were examined. The polyamines showed distinct activities, thus highlighting the importance of polyamine backbone structure. Interestingly, the rank order of polyamine ability for DNA compaction was different to that for their effects on circular dichroism and melting temperature, thus indicating that these polyamines have distinct effects on secondary and higher‐order structures of DNA. 相似文献