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Crystals of the organic semiconductor Cs 2 TCNQ 3 have been grown under the influence of magnetic field of 5 T and their optical properties have been compared with the crystals grown without magnetic field. The magnetic field effect manifests itself as the enhancement of the intradimer charge transfer band S 1 , which appears at around 1.3 eV in the E//a polarization. The high-pressure optical absorption measurements have shown that the S 1 band of the crystal grown at 5 T contains a new component, which is significantly intensified with increasing pressure up to 1 GPa, but diminishes as pressure increases further up to 4 GPa, and remains constant at higher pressures. This new component is additional to the component of S 1 band which has similar properties to that of the crystals grown without magnetic filed, which continuously grows up to 3 GPa and abruptly broadens out at higher pressures. The new component of S 1 is strongly linked to the ferromagnetism in this substance. 相似文献
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Local oscillations of the brane world are manifested as massive vector fields. Their coupling to the Standard Model can be obtained using the method of nonlinear realizations of the spontaneously broken higher-dimensional space–time symmetries, and to an extent, are model independent. Phenomenological limits on these vector field parameters are obtained using LEP collider data and dark matter constraints. 相似文献
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Reforming of dimethyl ether with carbon dioxide into synthesis gas has been carried out over a mixed catalyst containing Cu-based methanol decomposition catalyst and alumina. The catalyst is found to show a high activity and selectivity. Catalyst stability and deactivation mechanism was also examined. 相似文献
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Chiral polyaniline electrodes were prepared by the magneto-electropolymerization (MEP) method. Cyclic voltammograms (CVs)
of l-ascorbic acid (L-AA), d-isoascorbic acid (D-AA), and l-3-(3,4-dihydroxyphenyl)alanine were measured on the MEP polyaniline electrodes and their electrode reactions were electrocatalytic.
The CV peak currents varied depending on the chirality of the polyaniline and the optically active species, while the peak
potentials were independent of the chirality. The CVs of L-AA and D-AA were also measured on a Pt electrode in a (−)-camphor-10-sulfonic
acid supporting electrolyte solution, and the chiral behavior was observed in the peak potentials. It is considered that the
electrocatalytic process is responsible for the chiral electrochemical behavior on the polyaniline electrodes.
Contribution to special issue on “Magnetic field effects in Electrochemistry”. 相似文献
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Nitta Muneto Sasaki Shin Yokokura Ryo 《The European Physical Journal C - Particles and Fields》2018,78(9):1-12
The European Physical Journal C - The cosmological principle assumes that the universe is homogeneous and isotropic on cosmic scales. There exist many works testing the cosmic homogeneity and/or... 相似文献
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Yoshihisa Kurasawa Muneto Muramatsu Kaoru Yamazaki Setsuko Tajima Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1986,23(2):633-635
The chlorination of the α-hydrazonoester 4 with phosphoryl chloride/pyridine gave 3-[α-(o-chlorophenylhydrazono)methoxycarbonylmethyl]-2-chloroquinoxaline 5 , whose cyclization with 1,8-diazabicyclo[5,4,0]-7-undecene afforded 3-methoxycarbonyl-1-(o-chlorophenyl)-1H-pyrazolo[3,4-b]quinoxaline 6 . The reaction of 6 with hydrazine hydrate provided 3-hydrazinocarbonyl-1-(o-chlorophenyl)-1H-pyrazolo[3,4-b]quinoxaline 7 , whose reactions with methyl and allyl isothiocyanates furnished 3-(2,3-dihydro-4-methyl-3-thioxo-4H-1,2,4-triazol-5-yl)-1-(o-chlorophenyl)-1H-pyrazolo[3,4-b]quinoxaline 2 and 3-(4-allyl-2,3-dihydro-3-thioxo-4H-1,2,4-triazol-5-yl)-1-(o-chloropheny)-1H-pyrazolo[3,4-b]quinoxaline 8 , respectively. Moreover, the reactions of 7 with triethyl orthoformate and orthoacetate gave 1-(o-chlorophenyl)-3-(1,3,4-oxadiazol-5-yl)-1H-pyrazolo-[3,4-b]quinoxaline 9a and 1(o-chlorophenyl)-3-(2-methyl-1,3,4-oxadiazol-5-yl)-1H-pyrazolo[3,4-b]quinoxaline 9b , respectively. 相似文献