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81.
82.
Russian Physics Journal - Using spectral-kinetic data obtained for nanoassemblies based on CdSe/ZnS semiconductor quantum dots and tetrapyridylporphyrin molecules in methylcyclohexane-toluene... 相似文献
83.
A novel high‐temperature combustion interface for compound‐specific stable isotope analysis of carbon and nitrogen via high‐performance liquid chromatography/isotope ratio mass spectrometry
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84.
Eckhart E Gan KK Gwon C Hart T Honscheid K Hufnagel D Kagan H Kass R Pedlar TK Thayer JB Von Toerne E Wilksen T Zoeller MM Muramatsu H Richichi SJ Severini H Skubic P Dytman SA Mueller JA Nam S Savinov V Chen S Hinson JW Lee J Miller DH Pavlunin V Shibata EI Shipsey IP Cronin-Hennessy D Lyon AL Park CS Park W Thorndike EH Coan TE Gao YS Liu F Maravin Y Stroynowski R Artuso M Boulahouache C Bukin K Dambasuren E Khroustalev K Mountain R Nandakumar R Skwarnicki T Stone S Wang JC Mahmood AH 《Physical review letters》2002,89(25):251801
We report on a search for charmless hadronic B decays to the three-body final states K(0)(S)h(+)pi(-), K(+)h(-)pi(0), K(0)(S)h(+)pi(0) (h(+/-) denotes a charged pion or kaon), and their charge conjugates, using 13.5 fb(-1) of integrated luminosity produced near sqrt[s]=10.6 GeV, and collected with the CLEO detector. We observe the decay B-->K0pi(+)pi(-) with a branching fraction (50(+10)(-9)(stat.)+/-7(syst.))x10(-6) and the decay B-->K(*+)(892)pi(-) with a branching fraction (16(+6)(-5)(stat.)+/-2(syst.))x10(-6). 相似文献
85.
The mutual influence of two layers with strongly localized electrons is exercised though the random Coulomb shifts of site energies in one layer caused by electron hops in the other layer. We trace how these shifts give rise to a voltage drop in the passive layer, when a current is passed through the active layer. We find that the microscopic origin of drag lies in the time correlations of the occupation numbers of the sites involved in a hop. These correlations are neglected within the conventional Miller-Abrahams scheme for calculating the hopping resistance. 相似文献
86.
87.
H. Roos 《Physica A》1980,100(1):183-195
Given the C1-algebra of observables, the KMS condition is formulated in terms of the time evolution α1t of a set 0 ? () of “physical” states subject to certain natural conditions. α1t need not be defined by an automorphism group of . It is shown that, for a KMS state ω, α1t induces a 1-automorphism αωt of the von Neumann algebra πω()″ generated by the representation πω belonging to ω. 相似文献
88.
R.C. Greenwood C.W. Reich H.A. Baader H.R. Koch D. Breitig O.W.B. Schult B. Fogelberg A. B?cklin W. Mampe T. Von Egdy K. Schreckenbach 《Nuclear Physics A》1978,304(2):327-428
The level structure of 158Gd has been studied using the prompt γ-rays and conversion electrons emitted following neutron capture in 157Gd. The γ-ray energy and intensity measurements were made using both Ge(Li) detectors and a curved-crystal spectrometer. Conversion-electron energy and intensity measurements were made using two separate magnetic spectrometers: one to measure the primary electron spectrum and the other to measure the lower energy secondary electron spectrum. Some γ-γ coincidence measurements were also made among the secondary γ-rays. From these data, a neutron separation energy of 7937.1 ± 0.5 keV has been determined for 158Gd. A level scheme containing 59 excited states with energies < 2.25 MeV, for which de-excitation modes have been identified, is proposed for 158Gd. Many of these states have been grouped into rotational bands. A total of thirteen excited rotational bands with band-head energies below 2.0 MeV are contained in the level scheme. Features of the proposed level scheme include: the Kπ = 0?, 1? and 2? octupole-vibrational bands with band-head energies of 1263, 977 and 1793 keV, respectively; the γ-vibrational band at 1187 keV; three excited Kπ = 0+ bands with band-head energies of 1196, 1452 and 1743 keV; several two-quasiparticle bands with band-head energies in keV (and Kπ assignments) of 1380 (4+), 1636 (4?), 1847 (1+), 1856 (1?), 1920 (4+) and 1930 (1+). An analysis of (d, p) reaction data is presented which permits definite two-quasiparticle configuration assignments to be made to most of these latter bands. Evidence is presented which suggests strong mixing of some two-neutron and two-proton bands. A phenomenological four-band mixing analysis is made of the energy and E2 transition-probability data for the ground-state band and the three lowest-lying excited collective positive-parity bands. Good agreement with experiment is obtained. A Coriolis-mixing analysis of the octupole bands has been carried out and good agreement with the data on level energies and E1 transition probabilities to the ground-state band has been achieved. Values of Z, the ratio of the E1 transition matrix element with ΔK = 1 to that with ΔK = 0, involving the octupole bands and the first four 0+ bands are derived. For three of these 0+ bands, absolute values of these matrix elements are deduced. An interesting alternation in the sign of Z is observed for these four 0+ bands. 相似文献
89.
90.
The chromatographic behavior of the estrogen carbonyls, equilenin, equilin, and estrone, and their respective sodium borohydride reduction products has been studied. The separation of the 17 alpha-hydroxy reduced compounds is superior to the separations achieved for the parent carbonyls using both reversed-phase and normal-phase systems. The reductions appear quantitative by the chromatographic systems used but other work indicates that a small quantity of 17 alpha-hydroxy isomer is produced. The separations developed here have been used in the identification of 9-dehydroestrone, an impurity in estrone, and in the identification of the estrogens in a commercial aqueous suspension of estrogenic substances. 相似文献