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141.
The vanadium complex—pyrazine-2-carboxylic acid (PCA) system catalyzes oxidation of styrenes PhRC=CHR′ (R=H, Me; R′=H, Ph), or phenylacetylenes PhC=CR (R=H, Ph) with hydrogen peroxide in air to give aldehydes, ketones, and carboxylic acids. The reaction begins with H2O2 coordination to the vanadium ion followed by the formation of hydroxyl radicals. Catalytic action of PCA facilitates the reduction of the VV complex to the VIV complex and/or the stage of the formation of a peroxide derivative of vanadium. 相似文献
142.
The crosstalk between concentration changes in oxygenated haemoglobin and deoxygenated haemoglobin calculated by the modified
Lambert-Beer law in near-infrared topography is theoretically investigated. The changes in intensity detected with probe pairs
on the scalp caused by the concentration change in either oxygenated or deoxygenated haemoglobin induced by the focal brain
activation is predicted by Monte Carlo simulation. The topographic images of the changes in oxygenated and deoxygenated haemoglobin
are obtained from the changes in the intensity of light at two wavelengths detected by probe pairs to evaluate the crosstalk.
The crosstalk slightly depends on the positional relationship between the probe arrangement and the focal brain activation
and is minimised when the focal brain activation is located below a measurement point that is the midpoint between a probe
pair. The 690-/830-nm wavelength pair is practically effective for reducing the crosstalk, especially the crosstalk from oxygenated
haemoglobin to deoxygenated haemoglobin, in the NIR topography. 相似文献
143.
Synthesis of protein-silica hybrid hollow particles through the combination of protein catalysts and sonochemical treatment 总被引:1,自引:0,他引:1
Shiomi T Tsunoda T Kawai A Chiku H Mizukami F Sakaguchi K 《Chemical communications (Cambridge, England)》2005,(42):5325-5327
Hollow spherical particles with protein-silica hybrid shell structures have been synthesized through a combination of the catalytic activity of the protein and sonochemical treatment; the morphologies of the particles were controlled by varying the protein concentration. 相似文献
144.
Anisole and its homologues were carboxylated under the influence of CO and O2 catalyzed by Pd(OAc)2 combined with molybdovanadophosphates (HPMoV) under mild conditions to give the corresponding carboxylic acids in fair to good yields; for instance, anisole underwent the carboxylation under a mixed gas of CO (0.5 atm) and O2 (0.5 atm) in the presence of Pd(OAc)2 (5 mol%) and H5PMo10V2O40.nH2O (2 mol%) to form an isomeric mixture of anisic acids in good yield. 相似文献
145.
146.
T. Nakano M. Nakamura H. Sakaguchi M. Yosoi M. Ieiri H. Togawa S. Hirata O. Kamigaito H. M. Shimizu M. Iwaki Y. Nakai S. Kobayashi
T. Noro
H. Ikegami 《Physics letters. [Part B]》1990,240(3-4):301-305We have measured the angular distribution of the depolarization parameter Kyy′ in p-15N elastic scattering at 65 MeV. The deviation of Kyy′ from unity is large and indicates the existence of a nucleon-nucleus spin-spin interaction. The DWBA analysis shows that the measured Kyy′ data imply a large contribution from the tensor part of the spin-spin potential. 相似文献
147.
M. Sakaguchi H. Kinpara Y. Hori S. Shimada H. Kashiwabara 《Journal of Polymer Science.Polymer Physics》1987,25(7):1431-1437
The tetracyanoethylene anion radical (\documentclass{article}\pagestyle{empty}\begin{document}${\rm TCNE}^{ \cdot ^ - } $\end{document}) was detected by ESR spectroscopy in polytetrafluoroethylene (PTFE), which had been mechanically fractured in vacuo with tetracyanoethylene (TCNE) at 77 K. The assignment of \documentclass{article}\pagestyle{empty}\begin{document}${\rm TCNE}^{ \cdot ^ - } $\end{document} was carried out by ESR spectral simulation on the basis of an anisotropic effective hyperfine tensor that included a forbidden transition term. The \documentclass{article}\pagestyle{empty}\begin{document}${\rm TCNE}^{ \cdot ^ - } $\end{document} is formed by abstraction of an electron by TCNE from the anion that is produced by heterogeneous scission of the carbon-carbon bond in the main chain of PTFE. At least 16% of the scission of the main chains of PTFE occurs by a heterogeneous process to produce the anions. Approximately 50% of the anions decay during annealing for 30 min at 220 K in the dark, and all anions decay within 15 min at 325 K. 相似文献
148.
Low-lying states in 83Se have been studied through proton-induced isobaric analog resonance (IAR) reactions. Excitation functions for elastic and inelastic proton scattering were measured in the bombarding energy range 4.5– to 7.7 MeV. Angular distributions of proton inelastic scattering cross sections for the reaction 82Se(p, p')82Se(0.655 MeV 2+) and angular correlations of the inelastic protons and the associated 2+-0+ de-excitation γ-rays were measured on observed resonance peaks. In the analysis for the inelastic scattering, direct reaction contributions to the IAR were taken into account. Correlations between the low-lying states in 83Se and the excited 2+ core state are discussed. 相似文献
149.
K. Sakaguchi 《Colloid and polymer science》1977,255(1):101
Ohne Zusammenfassung 相似文献
150.
Ajimura S Hayakawa H Kishimoto T Kohri H Matsuoka K Minami S Mori T Morikubo K Saji E Sakaguchi A Shimizu Y Sumihama M Chrien RE May M Pile P Rusek A Sutter R Eugenio P Franklin G Khaustov P Paschke K Quinn BP Schumacher RA Franz J Fukuda T Noumi H Outa H Gan L Tang L Yuan L Tamura H Nakano J Tamagawa T Tanida K Sawafta R 《Physical review letters》2001,86(19):4255-4258
The spin-orbit splitting of Lambda single-particle states in (13)(Lambda)C was measured. The 13C(K-,pi(-))(13)(Lambda)C reaction was used to excite both the 1/2(-) and 3/2(-) states simultaneously, which have predominantly 12C(0(+)) x p(Lambda) configuration. gamma rays from the states to the ground state were measured in coincidence with the pi(-)'s, by which ls splitting was found to be 152+/-54(stat)+/-36(syst) keV. The value is 20-30 times smaller than exhibited by the ls splitting in the nuclear shell model. This value gives us new insight into the YN interaction. 相似文献