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141.
Pure rotational transitions of a rare gas atom-reactive open-shell triatom van der Waals complex Ar-HO2 have been observed by Fourier transform microwave spectroscopy. The transitions observed are of a type with K(a) = 0 and 1. Furthermore, by monitoring the change of the free induction decay signal of the a-type transitions, b-type transitions have been observed by a double resonance technique in the region 18-49 GHz. All these transitions provide us precise molecular constants. The r0 structure of Ar-HO2 has been determined by fixing the structure of the HO2 monomer. The determined structure is planar and almost T shaped, where the argon atom is slightly shifted to the hydrogen atom of HO2. The experimental data supplemented by high-level ab initio calculations indicate that the van der Waals bond of Ar-HO2 is relatively rigid. On the other hand, effects on the unpaired electron distribution by the complex formation are found to be fairly small, since the fine and hyperfine constants of Ar-HO2 are well explained by those of the HO2 monomer. 相似文献
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Yutaka Kawahara Wataru Takarada Masaki Yamamoto Yasuhito Kondo Kohji Tashiro Takeshi Kikutani 《Journal of Macromolecular Science: Physics》2020,59(7):440-456
AbstractVarious types of bicomponent fibers composed of polylactide (PLA) and poly(butylene terephthalate) (PBT) with different molecular weights, arranging the polymers separately in the skin or core, were produced by high-speed melt-spinning. The bicomponent spinning, arranging the PLA with high molecular weight (melt flow rate =1.9?g/10?min, L-lactide content = 98.7%) in the skin and the PBT with low molecular weight (IV = 0.835–0.865 dL/g) in the core, resulted in orientation-induced crystallization in the PLA component at the spinning speed of 2?km/min. This crystallization effect was ascribed to a chain-extending treatment applied to the original PLA (MFR = 4.0?g/10?min) to increase its molecular weight. By the treatment the PLA could crystallize when spun even at 1?km/min in its single-component spinning. On the other hand, the bicomponent spinning system interfered with the orientation-induced crystallization of PBT in the core. As a result, the critical spinning speed needed to generate the orientation-induced crystallization in the core PBT was elevated to 4?km/min. The inferior tensile behavior of the bicomponent fibers, as compared to the single-component PLA or PBT fibers, suggested poor compatibility between PLA and PBT. Transesterification reactions rarely occurred at the interface of the two polymers. The bicomponent fibers prepared from high molecular weight PLA and low molecular weight PBT, however, showed sufficient antibacterial activity and physical properties to be suitable for designing medical clothing materials. 相似文献
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Shin-ichiro Fujita Nobuhiro Iwasa Hiroaki Tani Wataru Nomura Masahiko Arai Nobutsune Takezawa 《Reaction Kinetics and Catalysis Letters》2001,73(2):367-372
For the title reaction, Cu/ZnO catalysts prepared from aurichalcite were more active than those prepared from other precursors.
Selectivity to ethyl acetate over Cu/ZnO was much higher than that over Cu/SiO2
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
147.
Nobukatsu Moridera Miki Yamamoto Wataru Okumura Masao Sugawara 《Analytical sciences》2007,23(1):39-44
A biotinylated glucose oxidase (bGOD)-immobilized glass disk was prepared for visualizing D-glucose fluxes in acute brain slices. A mouse hippocampal slice was placed on the bGOD disk and stimulated with a stimulant solution containing horseradish peroxidase (HRP) and a substrate DA-64, followed by capturing digital images of Bindschedler's Green (BG), an oxidized form of DA-64, with a CCD camera. The bGOD membranes responded proportionally to D-glucose, ranging from 2.0 to 5.0 mM. Sucrose, GABA, L-glutamic acid, L-aspartic acid, glycine, acetylcholine and L-ascorbic acid at 10 mM did not cause any responses. The D-glucose fluxes in mouse hippocampal slices stimulated by a hypoxia solution were neuronal region-dependent, i.e., dentate gyrus (DG), cornu ammonis 1 (CA1) and cornu ammonis 3 (CA3), while those stimulated by KCl was independent of the neuronal regions. The response of bGOD disks is discussed in terms of the principle, concentration dependence and selectivity. 相似文献
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Wataru Uchida Maiki Yoshikawa Tomohiro Seki Ryotaro Miki Toshinobu Seki Takashi Fujihara Yoshihiro Ishimaru Yuya Egawa 《Journal of inclusion phenomena and macrocyclic chemistry》2017,89(3-4):281-288
A boronic acid-appended γ-cyclodextrin (BA-CyD) was synthesized as a hybrid cross-linker of polyvinyl alcohol (PVA) to form a new type of hydrogel. The CyD moiety of BA-CyD forms an inclusion complex with the PVA chain to produce a mechanically interlocking structure. At the same time, the BA moiety of BA-CyD forms covalent bonds with the 1,3-diol moieties of PVA. On the basis of these two modes of interaction, the hybrid cross-linker connects two PVA chains, thus resulting in the formation of a hydrogel. To investigate the possibility of this hydrogel becoming the basis for an intelligent material for drug delivery, sugar-responsive drug release from the hydrogel was demonstrated. 相似文献