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91.
The triple-gluon vertex can be measured from the gluon jet spread using the energy-cone distribution functions. 相似文献
92.
The solid-state synthesis and properties are reported for a new polydiacetylene: poly[1,6-di(N-carbazolyl)-2,4-hexadiyne]. The monomer crystals polymerize quantitatively with γ irradiation or thermal annealing. An Autocatalytic effect is observed in both γ-ray polymerization and thermal polymerization and is attributed to an increase in chain propagation length at about 5% conversion. The activation energy for thermal polymerization is about 25 kcal/mole, independent of the degree of conversion to polymer. The exceptional thermal stability of the polymer crystals allowed a thermomechanical analysis over a large temperature range, ?50 to 300°C. With increasing temperature, the polymer contracts in the chain direction linearly with temperature over the entire range, yielding a thermal expansion coefficient of (?2.32 ± 0.02) × 10?5°C?1. Photoconductivity action spectra are reported for the polymer crystals. The energies for the photoconductivity onset (ca. 2.3 eV) and for the lowest energy optical transition (1.89 eV) are the lowest reported for the polydiacetylenes. The photoconduction onset is blue-shifted with respect to optical absorption—a result which is consistent with the excitonic assignment for the lowest energy optical transition in the polydiacetylenes. 相似文献
93.
Seven bands of the 1Π-X1Σ+ band system of P121Sb have been analyzed in detail. A large number of strong rotational perturbations in the v = 0 and 1 levels and a vibrational perturbation in the v = 0 level of the Π state have been observed. The term values of the rotational levels and rotational constants for the two isotopic species, P121Sb and P123Sb, are presented. 相似文献
94.
A new, vectorial approach to fast correlation attacks on binary memoryless combiners is proposed. Instead of individual input sequences or their linear combinations, the new attack is targeting subsets of input sequences as a whole thus exploiting the full correlation between the chosen subset and the output sequence. In particular, the set of all the input sequences can be chosen as the target. The attack is based on a novel iterative probabilistic algorithm which is also applicable to general memoryless combiners over finite fields or finite rings. To illustrate the effectiveness of the introduced approach, experimental results obtained for random balanced combining functions are presentedMost of this work was done while he was with Rome CryptoDesign Center, Gemplus, Italy 相似文献
95.
The motion of a holonomic scleronomic non-conservative mechanicalsystem with minimal dissipation is considered. As applicationsof the theory several problems are studied in detail. 相似文献
96.
K. C. Yee 《Journal of polymer science. Part A, Polymer chemistry》1979,17(11):3637-3646
Solid-state synthesis of a cyclically bound ladder polymer from a cyclic tetradiyne (cyclodotriaconta-1,3,9,11,17,19,25,27-octayne) is described. Irradiation of the colorless, needlelike monomer crystals with interstitially incorporated chloroform with 50 Mrad of 60Co γ-ray radiation results in red-brown polymer fibers in nearly quantitative yield. Infrared, Raman, and x-ray diffraction analyses of the polymer are consistent with polymerization by a 1,4-addition reaction at each diacetylene linkage to produce four fully conjugated chains joined together in pairs by a total of four ? (CH2)4? interchain linkages per 4.8-Å polymer repeat unit. Conformationally, it appears that the cyclic tetradiyne monomer polymerizes via a chair form. The results of the mechanical and thermal analyses indicate the presence of unreacted diacetylene functionality in the ladder polymer crystals. 相似文献
97.
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99.
Ae Ja Yee 《The Ramanujan Journal》2010,23(1-3):215-225
A partial theta series identity from Ramanujan’s lost notebook has a connection with some parity problems in partitions studied by Andrews in Ramanujan J., to appear where 15 open problems are listed. In this paper, the partial theta series identity of Ramanujan is revisited and answers to Questions 9 and 10 of Andrews are provided. 相似文献
100.
Investigating long-range correlation by the Hurst exponent, H, is crucial in the study of time series. Recently, empirical-mode-decomposition-based arbitrary-order Hilbert spectral analysis (EMD-HSA) has been proposed to numerically obtain without proof a scaling relationship, generated from the amplitude–frequency distribution, related to H. We propose a formalism to empirically study EMD-HSA, to deduce its scaling exponent ξ(q) from the perspective of EMD-based arbitrary-order Hilbert marginal spectrum (EMD-HMS), and to numerically compare the results with the expected H. EMD-HSA and EMD-HMS experiments show that, by incompletely removing (quasi-)periodic trends, the sunspot series should have an H value around 0.12. 相似文献