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1.
We complete our previous(1, 2) demonstration that there is a family of new solutions to the photon and Dirac equations using spatial and temporal circles and four-vector behaviour of the Dirac bispinor. We analyse one solution for a bound state, which is equivalent to the attractive two-body interaction between a charged point particle and a second, which remains at rest. We show this yields energy and angular momentum eigenvalues that are identical to those found by the usual method of solving of the Dirac equation,(4) including fine structure. We complete our previous derivation(2) of QED from a set of rules for the two-body interaction and generalise these. We show that QED may be decomposed into a two-body interaction at every point in spacetime. 相似文献
2.
Novel mixed valence states have been obtained by the treatment of cobaltous ferrocyanides (Co+2FeII) and ferricyanides (Co+2FeIII) in an ozone flow. The CN stretching bands occur at 2085 cm–1 for Co+2FeII and at 2160 cm–1 for Co+2FeIII. After the ozonization process of Co+2FeII, an intense band approximately at 2125 cm–1 is detected. This intermediate band must correspond to a mixed valence state of the type: FeII–CN–Co2+–NC–FeIII Mössbauer spectra recorded in situ during the ozonization of Co+2FeII show the presence of two components: a doublet with isomer shift and quadrupole splitting values close to the cobalti ferricyanide and a very broad line for the mixed valence state. From the Mössbauer and infrared spectra of the aged samples of the Co+2FeII after ozonization, a relaxation process to the initial state of the samples is observed but the mixed valence state is stable. 相似文献
3.
L. H. Tagle F. R. Diaz C. Margozzini 《Journal of Thermal Analysis and Calorimetry》1990,36(7-8):2521-2529
The thermal stability and kinetics parameters of polycarbonates and polythiocarbonates derived from diphenols with chlorinated aromatic side-rings were studied. The polycarbonates exhibited a higher thermal stability than the polythiocarbonates, except for polythiocarbonate Ib, which displayed similar behaviour to that of the analogous polycarbonate. The kinetic parameters of the thermal decomposition were determined by using the Arrhenius relationship and a computer program. In the considered temperature range, all the polymers degraded in a single stage with first-order kinetics.
The authors acknowledge financial support from the Dirección de Investigación of the Pontificia Universidad Católica de Chile. 相似文献
Zusammenfassung Es wurde die thermische Stabilität und die kinetischen Parameter von aus Diphenolen mit chlorierten aromatischen Nebenringen abgeleiteten Polycarbonate und Polythiocarbonate untersucht. Polycarbonate zeigen eine höhere thermische Stabilität als Polythiocarbonate. Eine Ausnahme bildet das Polythiocarbonat Ib, das in seinem Verhalten den Polycarbonaten gleicht. Mittels der Arrheniusschen Gleichung und einem Rechnerprogramm wurden die kinetischen Parameter der thermischen Zersetzung ermittelt. Im untersuchten Temperaturbereich zersetzen sich alle Polymere in einer einstufigen Reaktion erster Ordnung.
The authors acknowledge financial support from the Dirección de Investigación of the Pontificia Universidad Católica de Chile. 相似文献
4.
Carlos Cativiela Maria D. Diaz De Villegas Jos A. Mayoral Alberto Avenoza Miguel A. Roy 《Journal of heterocyclic chemistry》1988,25(3):851-855
3(5)-Carbomethoxy-4-hetarylpyrazoles 3 can be obtained by the aromatization of the corresponding cis-3-benzamido-3-carbomethoxy-4-hetaryl-Δ1-pyrazolines 2 obtained by 1,3-dipolar cycloaddition of diazo-methane with methyl Z-2-benzamido-3-hetarylpropenoates 1. An explanation, based on FMO theory, for the different reactivity of the dipolarophiles with diazomethane is given. 相似文献
5.
Marco-A. De Paoli R. J. Waltman A. F. Diaz J. Bargon 《Journal of polymer science. Part A, Polymer chemistry》1985,23(6):1687-1698
An electrically conductive plastic material was obtained by the electrochemical polymerization of pyrrole in a poly(vinyl chloride) matrix. The transmission electron microscopy shows that polypyrrole is uniformly distributed in the matrix. The conductivity of the composites fall in the range of 5 to 50 S/cm, and their mechanical properties, as measured in a stress—strain test, are very similar to those of pure poly(vinyl chloride). These can be further improved by addition of poly(chloroprene) rubber as a plasticizer. 相似文献
6.
The refined theory of the electroviscous lift forces is presented for the case when the separation distance between the particle and the wall is larger than the double-layer thickness. The theory is based on the lubrication approximation for motion of a long cylinder near a solid wall in creeping flow. The approximate analytical formula for the lift force valid for Pe=1 is derived and compared with the results of numerical calculations performed for an arbitrary Peclet number. The resulting electrokinetic lift force exceeds by several orders of magnitude one predicted by the previously developed theories of the lift force. The results for the electroviscous drag force indicate that when the double layer is thin compared with the particle size, the electroviscous drag is only a small correction (at most 10%) to the hydrodynamic drag force acting on a neutral particle moving near the wall. Copyright 2000 Academic Press. 相似文献
7.
J. E. Frederick S. B. Diaz I. Smolskaia W. Esposito T. Lucas C. R. Booth 《Photochemistry and photobiology》1994,60(4):356-362
Abstract Measurements of the UV solar irradiance are available from Ushuaia, Tierra del Fuego during the spring and summer seasons of 4 consecutive years beginning in 1989. In addition, column ozone amounts derived from satellite-based measurements exist for this location over the entire period from 1980 through 1991. Monthly mean column ozone over Ushuaia shows a general decline over the observing period, and a large day-to-day variability exists within a given month. Ozone amounts for the years 1980 through 1986 combined with a model of radiative transfer provide a climatological baseline against which to interpret the more recent ground-based irradiance data. We focus on monthly mean noontime irradiances integrated over 5 nm wide spectral bands near 305 nm and 340 nm, respectively. Measurements in the 340 nm band show that cloudiness has a large influence on both the absolute monthly mean irradiances and their interannual variability. For example, during December the 340 nm band irradiance varied from approximately 50% of the clear-sky value in 1992 to 65% in 1991. When the influence of cloudiness is removed, most of the months show irradiances in the 305 nm band that are larger than predicted from the climatological ozone amounts. The largest percentage enhancement occurred in October 1991 when the irradiance exceeded the baseline by 56%. The largest absolute irradiances occur in December, where the measurements range from 5.8% below the baseline in 1991 to 31% above in 1990. 相似文献
8.
C. Cativiela M. D. Diaz De Villegas E. Melndez 《Journal of heterocyclic chemistry》1985,22(6):1655-1657
Several Z-2-methyl(or phenyl)-4-[α-arylethylidene]-5(4H)-oxazolones 3Z, 4Z were prepared. The results obtained were compared by diazomethane insertion and condensation procedure. In order to synthesize E-2-phenyl-4-[α-arylethylidene]-5(4H)-oxazolones 4E hydrogen bromide isomerization in dry benzene was used. 相似文献
9.
The thermal behaviour of polycarbonates and polythiocarbonates derived from biphenols with methyl groups in the aromatic rings was studied by dynamic thermogravimetry. The thermal degradation temperatures (TDT) were determined, showing that polythiocarbonates are more stable than the corresponding polycarbonates. The kinetic parameters of the thermal decomposition were determined by using the Arrhenius relationship, and showed two steps for the degradation of the polycarbonates, the first being a zero-order process and the second having first-order kinetics; the steps were associated with two different reaction mechanisms. Polythiocarbonates degraded according to first-order kinetics. 相似文献
10.
Stereoselective synthesis of trans-2,3-disubstituted pyrrolidines via addition to N-acyliminium ions
An efficient and stereoselective synthesis of trans-2,3-disubstituted pyrrolidines is described. The intermolecular alkylation of racemic N-acyliminium ions generated in situ from the corresponding 3-substituted lactams proceeds stereoselectively and in high yield. 相似文献