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S. K. So M. H. Chan L. M. Leung 《Applied Physics A: Materials Science & Processing》1995,61(2):159-161
Photothermal Deflection Spectroscopy (PDS) is known to be one of the most sensitive techniques for measuring the absorption of weakly absorbing materials. We have applied PDS for measuring the optical absorption of a few polymer thin-film samples over the wavelength region from 0.4–2.0 m. The results are useful for optical evaluation of these polymers. 相似文献
954.
Pui-Fai Leung 《Geometriae Dedicata》1995,56(1):5-6
S. T. Yau proved inAmer. J. Math.
97 (1975), p. 95, Theorem 15 that if the sectional curvature of ann-dimensional compact minimal submanifold in the (n + p)-dimensional unit sphere is everywhere greater than (p – 1)/(2p – 1), then this minimal submanifold is totally geodesic. In this note we improve this bound for the casep 2 to (3p – 2)/(6p). 相似文献
955.
It is known that a strongly regular semi-Cayley graph (with respect to a group G) corresponds to a triple of subsets (C, D, D) of G. Such a triple (C, D, D) is called a partial difference triple. First, we study the case when D D is contained in a proper normal subgroup of G. We basically determine all possible partial difference triples in this case. In fact, when
nor 25, all partial difference triples come from a certain family of partial difference triples. Second, we investigate partial difference triples over cyclic group. We find a few nontrivial examples of strongly regular semi-Cayley graphs when |G| is even. This gives a negative answer to a problem raised by de Resmini and Jungnickel. Furthermore, we determine all possible parameters when G is cyclic. Last, as an application of the theory of partial difference triples, we prove some results concerned with strongly regular Cayley graphs. 相似文献
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Rabinowitz SA Arroyo C Bachmann KT Bazarko AO Bolton T Foudas C King BJ Lefmann WC Leung WC Mishra SR Oltman E Quintas PZ Sciulli FJ Seligman WG Shaevitz MH Merritt FS Oreglia MJ Schumm MJ Bernstein RH Borcherding F Fisk HE Lamm MJ Marsh W Merritt KW Schellman HM Yovanovitch DD Bodek A Budd HS de Barbaro P Sakumoto WK Kinnel T Sandler PH Smith WH 《Physical review letters》1993,70(2):134-137
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P. H. Sandler T. S. Kinnel W. H. Smith K. Bachmann R. Blair C. Foudas B. King W. C. Lefmann W. C. Leung S. R. Mishra P. Z. Quintas S. A. Rabinowitz F. Sciulli W. seligman M. H. Shaevitz F. S. Merritt M. J. Oreglia H. Schellman B. Schumm R. H. Bernstein F. Borcherding M. J. Lamm W. Marsh D. Yovanovitch A. Bodek H. S. Budd P. de Barbaro W. K. Sakumoto 《Zeitschrift fur Physik C Particles and Fields》1993,57(1):1-12
The rate of neutrino- and antineutrino-induced prompt same-sign dimuon production in steel was measured using a sample of μ?μ? events and 25 μ+μ+ events withP μ>9 GeV/c, produced in 1.5 millionv μ and 0.3 million \(\overline {v_\mu }\) induced charged-current events with energies between 30 GeV and 600 GeV. The data were obtained with the Chicago-Columbia-Fermilab-Rochester (CCFR) neutrino detector in the Fermilab Tevatron Quadrupole Triplet Neutrino Beam during experiments E 744 and E 770. After background subtraction, the prompt rate of same-sign dimuon production is (0.53±0.24)×10?4 perv μ charged-current event and (0.52±0.33)×10?4 per \(\overline {v_\mu }\) charged-current event. The kinematic distributions of the same-sign dimuon events after background subtraction are consistent with those of the non-prompt background due to meson decays in the hadron shower of a charged-current event. Calculations ofc \(\bar c\) gluon bremsstrahlung, based on improved measurements of the charm mass parameter and nucleon structure functions by the CCFR collaboration, yield a prompt rate of (0.09±0.39)×10?4 perv μ charged-current event. In this case,c \(\bar c\) gluon bremsstrahlung is probably not an observable source of prompt same-sign dimuons. 相似文献
960.