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31.
The reaction cross section σRpA(E) for proton-nucleus collisions varies with energy as the total cross section σtpN(E) does for proton-nucleon scattering in the energy regime 100 MeV ? E ?400 GeV. We propose several empirical relations, and test them by a χ2 analysis of various data. Within the framework of Glauber theory, the parameters in the relations can be linked to the cross section for a single inelastic collision. 相似文献
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E. Eisenhandler W.R. Gibson C. Hojvat P.I.P. Kalmus L.C.Y.Lee Chi Kwong T.W. Pritchard E.C. Usher D.T. Williams M. Harrison W.H. Range M.A.R. Kemp A.D. Rush J.N. Woulds G.T.J. Arnison A. Astbury D.P. Jones A.S.L. Parsons 《Physics letters. [Part B]》1973,47(6):531-535
We present measurements from a spark chamber experiment of the differential cross-sections for p → π?π+, K?K+ at 20 momenta in the range 0.8–2.4 GeV/c (c.m. energy 2.02 to 2.57 GeV). The c.m. angular range was . There are about 2000π?π+ events and about 300 K?K+ events at each momentum. 相似文献
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In order to obtain a better understanding of the X1Σ+ ground state and the A1Σ+ state potential energy curves of lithium hydride and to examine in detail the concept of “mass-reduced quantum numbers” for both an ordinary (X1Σ+) and an anomalous (A1Σ+) electronic state, the emission spectra of the A1Σ+ → X1Σ+ bands of the isotopic lithium hydrides and deuterides were photographed in the 3000–5000-Å region with a 3.4-m Ebert Spectrograph. The bands found involved v″ = 0 to 7 to various v′ = 0 to 17 for 6LiH, and v″ = 0 to 7 to various v′ = 1 to 16 for 6LiD. Additional bands involving v″ = 4 and 5 were also found for 7LiH. The vibrational-rotational spectroscopic analysis of 7LiH, 6LiH, and 6LiD are reported here, as are the reanalyses of the 7LiH and 7LiD data reported by Crawford and Jorgensen. New Rydberg-Klein-Rees (RKR) A1Σ+ and X1Σ+ potential curves have been constructed for each individual molecule and are reported, but detailed isotopic comparisons will be reported in subsequent publications. 相似文献
36.
Computer graphics-assisted applications of first-order chemical kinetics are applied to absorbance data from spectrophotometric measurements of the decomposition of di-μ-hydroxobis[dioxalatocobaltate(III)] (at pH 4.0) and trioxalatocobaltate(III) (in 1.0 M perchloric acid) in order to estimate the purity of the complexes. A program called KINFIR is used. 相似文献
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We present a theoretical analysis for laser cooling of bulk GaAs based on a microscopic many-particle theory of absorption and luminescence of a partially ionized electron-hole plasma. Our cooling threshold analysis shows that, at low temperatures, the presence of the excitonic resonance in the luminescence is essential in competing against heating losses. The theory includes self-consistent energy renormalizations and line broadenings from both instantaneous mean-field and frequency-dependent carrier-carrier correlations, and it is applicable from the few-Kelvin regime to above room temperature. 相似文献
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Palladium‐Catalyzed Regioselective Aromatic Extension of Internal Alkynes through a Norbornene‐Controlled Reaction Sequence
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Dr. Qingyang Zhao Dr. Wai Chung Fu Prof. Dr. Fuk Yee Kwong 《Angewandte Chemie (International ed. in English)》2018,57(13):3381-3385
A regioselective aromatic π‐extension reaction of internal alkynes is reported. The proposed method employs three easily available components, namely aryl halides, 2‐haloarylcarboxylic acids, and disubstituted acetylenes. The transformation is driven by a controlled reaction sequence of C?H activation, decarboxylation, and annulation to give poly(hetero)aromatic compounds in a site‐selective fashion. Unlike in previously reported palladium‐catalyzed three‐component annulations, alkyne carbopalladation is the last step of this tandem reaction. 相似文献