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251.
252.
253.
A. Soni 《Physics letters. [Part B]》1977,71(2):435-438
Characteristics of trimuons emerging from cascade decay of two new hadronic quantum numbers are compared with experiments. The possibility that the lower (spinless) member decays preferentially into Perl's sequential heavy lepton τ via τ + ντ is incorporated. 相似文献
254.
255.
Gupta VP Thul P Mishra S Pratap R Ram VJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,72(1):82-101
A systematic study has been conducted on the conformation, electronic structure and vibrational spectra of benzo[c]phenanthrene and some of its partially reduced derivatives by experimental infrared spectroscopic and quantum chemical techniques. Electrostatic potential surfaces have been mapped over the electron density isosurfaces to obtain information about the size, shape, charge density distribution and chemical reactivity of the molecules. Possibility of hydrogen-hydrogen bonding has been explored in all the molecules. Partial reduction of the aromatic rings in benzo[c]phenanthrene leads to considerable molecular distortion with the approximate mean angle between the terminal rings increasing from 27.3 degrees to 46.0 degrees . The distortion is unequally distributed near the aromatic and saturated rings; the latter absorbs most of strain due to flexibility of the rings. A complete vibrational analysis of the experimental infrared spectra has been reported on the basis of frequency and intensity of the vibrational bands and potential energy distribution over the internal coordinates and characteristic bands have been identified. 相似文献
256.
For Dynkin labels of weights in 5 and 10 of SU(5), 10 and 16 of SO(10) and 27 ofE, we find it instructive to (a) explōit the Cartan decom position into a nonsemi simple symmetric subalgebra and coset space,
(b) introduce a set of annihilation and creation operators, that may act on an invariant 10>, to represent suitably the shift-action
and weight-vectors. 相似文献
257.
258.
Stable, reproducible high temperature superconductivity with onset temperatures of 90 K and above is confirmed in the oxide
system with nominal metal ion composition BiSrCaCu2O
x
. The onset is nearly the same, but zero-resistance temperatures depend on the heat treatment. Sample quenched from 850 C
in air (close to melting) to liquid nitrogen temperature is non-superconducting. BiSr0.5Ca1.5Cu2O
x
is also found to be superconducting in which a two-step drop in resistance is observed, one starting around 118 K and the
other around 80 K. 相似文献
259.
260.
S. J. Guerrero A. Keller P. L. Soni P. H. Geil 《Journal of Polymer Science.Polymer Physics》1980,18(7):1533-1559
An enquiry is presented into the nature and origin of thermoreversible gelation of poly(vinyl chloride) (PVC). In line with a previous paper it is demonstrated by direct x-ray diffraction evidence that the origin of the gelation is crystallization, and that this crystallinity can be conspicuously apparent even for the usual technological polymer. In addition some unusual diffraction effects become apparent such as do not obviously follow from existing notions of the PVC structure. Combined infrared dichroism and x-ray studies revealed that these new effects are attributable to a two-component nature of the crystallinity where the components are distinguished by their orientation behavior, lateral extension, and possibly morphology of the crystallites. Some of the crystals orient with their a axes (type A crystals) and some with their c axes (type B crystals) along the stretch direction. Other more complex orientability differences are also manifest during film formation. Crystals B are smaller, and are believed to correspond to the network forming junctions, hence to fringed micellar crystals. Crystals A have a less evident connection with the network and are hypothesized to be of lamellar character, the behavior of which is closely simulated by lamellar crystal additives (stabilizer crystals). High-temperature x-ray work revealed no melting of crystals even in the temperature range where endotherms appear in the thermograms. 相似文献