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91.
Visible‐Light‐Mediated Addition of α‐Aminoalkyl Radicals to [60]Fullerene by Using Photoredox Catalysts
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Dr. Yoshihiro Miyake Yuya Ashida Dr. Kazunari Nakajima Prof. Dr. Yoshiaki Nishibayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(20):6120-6125
The functionalization of fullerene has been extensively studied and various fullerene derivatives have been synthesized. We have succeeded in the functionalization of [60]fullerene by using α‐aminoalkyl radicals generated by visible‐light‐mediated single‐electron oxidation of α‐silylamines as synthetic intermediates. In these reactions, the introduction of diarylamino groups, which are useful electron donors, has been easily achieved. 相似文献
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Akon Higuchi Tadashi Nakajima Atsushi Morisato Michiaki Ando Kazukiyo Nagai Tsutomu Nakagawa 《Journal of Polymer Science.Polymer Physics》1996,34(13):2153-2160
Infrared spectra of CO2 sorbed in rubbery and glassy polymeric membranes were measured to examine the relationships between the spectroscopic data and the physical properties of the membranes. The two peaks observed in the spectra of CO2 were attributed to the R branch and P branch of CO2 sorbed in the membranes based on the consideration that both peaks were observed at a temperature above the glass transition temperature of the membranes. Apparent diffusion coefficients of CO2 in the membranes were measured from the desorption kinetics of CO2 detected by FTIR spectroscopy. The solubility coefficients of CO2 were also estimated from absorbance spectra of CO2 sorbed in the membranes using Lambert-Beer's rule. The permeability, solubility, and diffusion coefficients estimated by the FTIR method were found to correlate well with the coefficients obtained by conventional methods such as vacuum-pressure or sorption isotherm methods. © 1996 John Wiley & Sons, Inc. 相似文献
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Toshio Nishi Hideyuki Nukaga So Fujinami Ken Nakajima 《高分子科学》2007,(1):35-41
Atomic force microscopy (AFM) has the advantage of obtaining mechanical properties as well as topographic information at the same time. By analyzing force-distance curves measured over two-dimensional area using Hertzian contact mechanics, Young's modulus mapping was obtained with nanometer-scale resolution. Furthermore, the sample deformation by the force exerted was also estimated from the force-distance curve analyses. We could thus reconstruct a real topographic image by incorporating apparent topographic image with deformation image. We applied this method to carbon black reinforced natural rubber to obtain Young's modulus distribution image together with reconstructed real topographic image. Then we were able to recognize three regions; rubber matrix, carbon black (or bound rubber) and intermediate regions. Though the existence of these regions had been investigated by pulsed nuclear magnetic resonance, this paper would be the first to report on the quantitative evaluation of the interfacial region in real space. 相似文献
95.
Spatial and seasonal variations in attenuation of solar ultraviolet radiation in Lake Biwa, Japan 总被引:2,自引:0,他引:2
Seasonal changes in diffuse ultraviolet (UV) and visible light attenuations and inherent optical properties in the lake water were monitored at the pelagic and littoral shallow zones of Lake Biwa which features a broad range of optical conditions within a single large water body. We considered the absorption factors that affect UV attenuation, and clarified the contribution of the absorption of suspended particles and chromophoric dissolved organic matter (CDOM) by multiple regression analyses of the monitoring data. The variability of UV attenuations in the lake demonstrated a strong contrast between the pelagic and the shallow zones. The latter were characterized by turbid systems supplying suspended matter as well as CDOM, whereas the former was far from the turbid systems in the littoral zone or the lake bottom. In this lake, the regulation of UV and light attenuations is rendered competitive by the absorption of suspended particles and CDOM in the lake water, hence, the UV penetration has both spatial and temporal variability based on changes in the physical and biological condition of the lake. 相似文献
96.
Moment analysis method using partial filling CE was developed for the kinetic study on solute permeation at the interface of spherical molecular aggregates. Moment equations for partial filling CE were developed by classifying CE systems into five categories according to the migration velocities of solute and molecular aggregate. The method was applied to the study on the dissolution of electrically neutral solutes into SDS micelles. Elution peaks were measured by partial filling CE while changing the concentration of SDS and the filling ratio of SDS micellar zone to the capillary (ϕM). Partition equilibrium constants (Kp) and rate constants of interfacial solute permeation of SDS micelles (kin and kout) were determined from the first absolute and second central moments of the elution peaks by using the moment equations. Their values were comparable irrespective of ϕM and were almost the same as those previously measured by complete filling CE. The positive correlation of Kp with the hydrophobicity of the solutes was explained in terms of the change in kin and kout. It was demonstrated that the moment analysis method using partial filling CE is effective for studying solute permeation kinetics at the interface of spherical molecular aggregates. 相似文献
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We revisited the vanadium oxide phosphors, AVO3 (A:K, Rb, and Cs) and M3V2O8 (A:Mg and Zn) for a revaluation of possibility of these compounds for lighting applications, and the internal quantum efficiency (η) and luminescent colour properties for AVO3 (A:K, Rb, and Cs) and M3V2O8 (A:Mg, and Zn) have been presented. The AVO3 showed the broadband emission from 380 to 800 nm, and the η for the KVO3, RbVO3 and CsVO3 were 4%, 79% and 87%, respectively. The CIE colour coordinates are located at white region on the chromaticity diagram. The M3V2O8 (A:Mg and Zn) also exhibited a quite broadband emission between 410 and 900 nm, indicating yellow luminescent colour. The Zn3V2O8 showed high η value, 52%, compared to that of the Mg3V2O8 (η=6%). This enhancement of η in the Zn3V2O8 could be due to the increasing exciton diffusion assisted by the hybridizations of Zn 3d and O 2p orbitals for the valence band, and Zn 4s and Ti 3d orbitals for the conduction band. 相似文献