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61.
Frank J. Owens 《Theoretical chemistry accounts》1981,60(4):363-368
A simple formalism is developed to calculate the rate of internal vibrational excitation of a molecule in a lattice due to abrupt deformation of the bonds of the molecule as a result of the application of a shock pulse to the lattice. The excitation rate is calculated as a function of rise time of the pulse and peak pressure for the case of 1,3,5-trinitro, 1,3,5-triazocyclohexane. It is shown that large vibrational excitation rates can be achieved if the rise time of the shock pulse is in the order of the period of vibration of the bond. The possible role of this process in shock induced chemical reactions in solids is considered. 相似文献
62.
Determination of boron in international silicate reference materials with an argon plasma is demonstrated. Detection limits are about 5 ppm for rock samples. 相似文献
63.
A formalism for discussing the spin dependence of inclusive reactions is presented. The role of various constraints following from conservation of parity and angular momentum conservation is discussed. Expressions for specific single and double polarization observables are presented. Predictions of the triple-Regge model for these observables are given. 相似文献
64.
New data are presented, in the form of statistical tensors, for the reactions π+p → (?0, ω)Δ++ at 7.1 GeV/c. Using these data, two types of model-dependent amplitude analyses have been performed. Both analyses, though based on different sets of assumptions, yield results which are in agreement with each other. The structure observed in the magnitudes and phases of the extracted amplitudes is consistent with that expected on the basis of currently accepted phenomenological ideas. 相似文献
65.
F.J. Owens 《Chemical physics letters》1973,18(2):158-160
The s and the p density of the sp hybrid orbital of the unpaired electron on the central nucleus of CO?2 and BF2 are calculated as a function of the bond angle by the INDO molecular orbital method. The theory yields a dependence of the ratio of the p density to the s density on bond angle markedly different from a dependence derived from the orthogonality of sp hybrid orbitals and commonly used to determine the bond angle from ESR data. 相似文献
66.
F. Dibianca R.L. Eisner W. Fickinger J.A. Malko D. Matthews J. OReilly J.F. Owens D.K. Robinson S.U. Chung S.D. Protopopescu 《Physics letters. [Part B]》1976,63(4):461-465
Data are presented on the reactions π+n → ?0+X and , respectively. Comparisons are made with related reactions at higher energies. 相似文献
67.
A gas-liquid chromatographic procedure is presented for the determination of therapeutic and toxic serum levels of doxepin and loxapine, using a nitrogen-phosphorus-sensitive detector. Amitriptyline is used as the internal standard. The method is accurate, sensitive and specific with no derivatization required prior to analysis. An advantage of the procedure is the small serum sample size needed for analysis and the selectivity and sensitivity of the detector, with the limit of detection being 3 and 2 microgram/l for doxepin and loxapine, respectively. Nine cases of doxenin and loxapine misuse are presented. Serum doxepin concentrations ranged from 113 to 439 microgram/l, with a loxapine concentration of 192 microgram/l observed in one patient. The presence of the tricyclics was identified and confirmed by gas chromatography-mass spectrometry and the mass spectrum of loxapine is reported. 相似文献
68.
69.
The 16O(γ, po) reaction has been investigated between photon energies Eγ = 40 and 105 MeV using a bremsstrahlung beam, full angular distributions being obtained at Eγ = 60, 80 and 100 MeV. While cross-section calculations which introduce a residual interaction of Yukawa form agree well with the data, the need for further work is indicated. 相似文献
70.
Abstract— Single-strand breaks are produced in the phosphodiester backbone of ultraviolet-light-irradiated 5–bromodeoxyuridine-containing DNA (BU-DNA) after treatment with alkali. No radiation dependent breakage is observed in thymine-containing DNA (thy-DNA). The relative yields of breaks terminated by 5'-hydroxyl and 5'-phosphate groups was determined by measuring the rate of phosphorylation achieved with polynucleotide kinase in BU-DNA single strands before and after treatment with alkaline phosphatase. The ratio of 5'-phosphate to 5' hydroxyl groups ranged from 2.3 to 2.9 in different experiments. When cysteamine was present during irradiation no new end groups were produced.
In order to identify the nucleoside(s) at the 5'-termini, phosphate groups were removed with alkaline phosphatase and the 5'-hydroxyl groups were phosphorylated with polynucleotide kinase. Electrophoresis of enzymatic digests showed a single32 P-labeled component migrating more rapidly than any of the four usual 5'-mononucleotides. Upon column chromatography this component resolved into a major peak coincident with 5'-dUMP and a lesser unidentified constituent. No 5'-dBUM32 P was observed among these nucleotides. 相似文献
In order to identify the nucleoside(s) at the 5'-termini, phosphate groups were removed with alkaline phosphatase and the 5'-hydroxyl groups were phosphorylated with polynucleotide kinase. Electrophoresis of enzymatic digests showed a single