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71.
72.
A vibrational and rotational analysis is presented for the D′ → A′ transition (2800–2950 Å) of Br2. The analysis includes 11 rotationally analyzed bands for 79Br2 and 3 for 81Br2, plus bandheads for 70 additional v′-v″ bands of 79Br2, 81Br2, and 79Br81Br. The latter include some violet-degraded and spikelike features at the long-wavelength end of the spectrum, which are interpreted and assigned with the aid of band profile simulations. The assigned features are fitted directly to 14 vibrational and rotational expansion parameters for the two electronic states, from which the following spectroscopic constants are obtained: ΔTe = 35706 cm?1, ω′e = 150.86 cm?1, ω″e = 165.2 cm?1, B′e = 0.042515 cm?1, B″e = 0.05944 cm?1, , . The spectroscopic parameters are used to calculate RKR potentials and Franck-Condon factors for the transition. 相似文献
73.
Uhlig F Förster A Böttcher I Debowski M Dohrmann F Grosse E Koczoń P Kohlmeyer B Laue F Menzel M Naumann L Oeschler H Scheinast W Schwab E Senger P Shin Y Ströbele H Sturm C Surówka G Wagner A Waluś W;KaoS Collaboration 《Physical review letters》2005,95(1):012301
Azimuthal distributions of pi+, K+, and K- mesons have been measured in Au+Au reactions at 1.5A GeV and Ni+Ni reactions at 1.93 A GeV. In semicentral collisions at midrapidity, pi+ and K+ mesons are emitted preferentially perpendicular to the reaction plane in both collision systems. In contrast for K- mesons in Ni+Ni reactions, an in-plane elliptic flow was observed for the first time at these incident energies. 相似文献
74.
75.
G. S. Sur S. K. Noh Sam K. Choi 《Journal of polymer science. Part A, Polymer chemistry》1981,19(2):223-233
N-acryloyl pyrrolidone (NAP) was synthesized by reaction of pyrrolidone with acryloyl chloride. First, the polymerization of NAP and copolymerization of NAP with styrene (St) were carried out at 60°C, using 2,2′-azobisisobutyronitrile (AIBN) as an initiator. Kinetic studies showed that the rate of polymerization (Rp) could be expressed by Rp = K [AIBN]0.5 [NAP]1.0. The reactivity of NAP was found to be larger than that of N-methacryloyl pyrrolidone. The overall activation energy was calculated to be 24.3 kcal mole?1. The following monomer reactivity ratio and Q and e values were obtained. NAP(M1)—St(M2): r1 = 1.50, r2 = 0.35, Q1 = 0.42, and e1 = 1.60. Second, graft copolymers were synthesized by reacting pyrrolidone, in the presence of a catalytic amount of its potassium salt, with poly(NAP-co-St). 相似文献
76.
77.
B. Singh H. W. Taylor E. Browne H. L. Hall E. B. Norman R. M. Larimer A. O. Macchiavelli K. T. Lesko B. Sur 《Zeitschrift für Physik A Hadrons and Nuclei》1992,341(3):249-253
This paper presents a study of the rays from the electron capture decay of 3.63d
100Pd. Singles and coincidence measurements provided an accurate determination of-ray intensities and an improved knowledge of the100Rh level scheme. Experimental evidence supports excitation of levels in100Rh at 86-, 136- and 154 keV, not previously reported from the decay of100Pd.On leave from Departamento de Fisica, Comision Nacional de Energia Atomica, Buenos Aires, Argentina 相似文献
78.
Reaction of 1-nitrotriphenylene ( 7a ) with triethylphosphite (Cadogan reaction) produces 4H-naphtho[1,4-def]carbazole, a likely component of fossil fuels. Surprisingly 7a and its 2-isomer are obtained from treatment of triphenylene with sulfuric acid/trifluoroacetic anhydride in nitromethane. Correlation between ultraviolet spectra and substitution reactions in peri-condensed pyrroles and thiophenes is presented. 相似文献
79.
Zusammenfassung Eine makro- und mikrotitrimetrische Methode zur Bestimmung von Magnesium mit ÄDTA in 60%iger äthanolischer Lösung gegen Methylthymolblau wurde ausgearbeitet. Durch Anwendung von Äthanol wird der Farbwechsel verschärft, die Indikatorblockierung durch Spuren von Kupfer(II) beseitigt und die Ergebnisse verbessert.
Summary A macro- and micro-titrimetric method has been developed for the determination of magnesium with EDTA in 60% ethanolic solution using methylthymol blue as indicator. The use of ethanol sharpens the color change, the blocking of the indicator by traces of copper is eliminated, and the results improved.相似文献
80.
Amit Sur Joel L. Lebowitz J. Marro M. H. Kalos S. Kirkpatrick 《Journal of statistical physics》1976,15(5):345-353
The site-percolation problem on a simple cubic lattice is studied by the Monte Carlo method. By combining results for periodic lattices of different sizes through the use of finite-size scaling theory we obtain good estimates forp
c (0.3115±0.0005), (0.41±0.01), (1.6±0.1), and(0.8±0.1). These results are consistent with other studies. The shape of the clusters is also studied. The average surface area for clusters of sizek is found to be close to its maximal value for the low-concentration region as well as for the critical region. The percentage of particles in clusters of different sizesk is found to have an exponential tail for large values ofk forP <p
c. Forp >p
c there is too much scatter in the data to draw firm conclusions about the size distribution.Work supported in part by USAFOSR Grant #73-2430B and by ERDA #E(11-1)-3077. 相似文献