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101.
102.
The relationship between mixture flow parameters and the combustion noise from open turbulent premixed gaseous flames is investigated experimentally and it is shown how the overall noise levels and frequency spectra are related to certain flow and geometric parameters and to the turbulence structure of the combustible mixture. 相似文献
103.
The splitting of trajectories with non-vacuum quantum numbers is discussed within the dual unitarisation scheme. The estimated difference in intercepts between vector-tensor trajectories of opposite signatures, such as ? ? A2 and , agrees both in sign and magnitude with that deduced from phenomenological analyses. 相似文献
104.
Clive A. Croxton 《Physics letters. A》1979,70(5-6):441-443
The configurational and thermodynamic properties of an athermal polymer system are determined at intermediate to high concentrations. 相似文献
105.
C.J. Batty S.F. Biagi M. Blecher R. Kunselman R.A.J. Riddle B.L. Roberts J.D. Davies G.J. Pyle G.T.A. Squier D.M. Asbury M. Leon 《Nuclear Physics A》1978,296(3):361-372
The attenuation due to the E2 nuclear resonance effect has been measured in hadronic atoms using pions with 111Cd and 112Cd, and for kaons with 122Sn. Energies of the relevant X-ray and γ-ray transitions and of the X-ray cascade intensities have also been measured so as to give a self-consistent set of information. The results are found to be in very good agreement with theoretical calculations. 相似文献
106.
C. A. Peridier J. L. Matthews M. J. Leitch H. Jeremie M. Irshad B. L. Roberts 《Zeitschrift für Physik A Hadrons and Nuclei》1983,310(4):317-328
The cross section for the3He(γ, 2p) reaction has been measured in a complete kinematics experiment in the energy rangeE γ=80–170 MeV, forθ P1=θ P2=90°. This configuration was selected in order to investigate the role of proton-proton final state interactions in the three-body breakup process. The measured proton spectra are seen to be consistent with a prediction using the Watson-Migdal formalism. The magnitude of the observed cross section clearly indicates an enhancement over phase space, presumably due to the strong proton-proton interaction in the final state. The experimental results agree, within their limited statistical accuracy, with a theoretical calculation which includes this effect. 相似文献
107.
Robert E. Botto Philip W. Westerman John D. Roberts 《Magnetic resonance in chemistry : MRC》1978,11(10):510-515
15N chemical shifts of the Z and E isomers of twenty-two ketoximes and fourteen aldoximes have been determined at the natural-abundance level of 15N, using Fourier transform methods. The influences of π delocalization, methyl substituents and solute concentration on the oxime nitrogen shielding have been determined. The 15N shifts for oximes of several cycloalkanones have been measured and the influence of ring size on the chemical shifts is discussed. 相似文献
108.
Abstract— Radiation-induced covalent binding of labelled carcinogens to DNA has been investigated under a variety of conditions using ultrafiltration or millipore filtration of TCA precipitable complexes. High yields of carcinogen binding at high DNA concentrations are also observed for a variety of small molecules and are not carcinogen-specific. At high carcinogen concentrations, radiation-induced unstable electrophilic carcinogenic species are produced, and undergo free-radical reactions which simulate cellular redox reactions involved in metabolic carcinogen activation, leading to the formation of covalently bound carcinogen adducts to DNA as a potential target macromolecule. The yields of carcinogen-DNA adducts increase linearly with dose and depend upon carcinogen concentration. The results of scavenger studies indicate that the oxidising species O2 - and OH are the principal activating species. Rate constants for the selective radiation-induced oxidation reactions of various chemical carcinogens with superoxide have been measured by a competition kinetic method using pulse radiolysis. The relatively long-lived superoxide radical reacts with carcinogens at a rate which is two orders of magnitude slower than the diffusion-controlled rate for the hydroxyl radical, thus allowing a measure of O2 - specificity in the presence of competing reactants within the cell. 相似文献
109.
Peter Roberts 《The Journal of the Operational Research Society》1983,34(1):71-79
A new theory of the learning process is proposed, based on the assumption that learning resembles a search programme using the branch and bound algorithm. Examples from diverse fields are given, and means of testing the theory are suggested. It is argued that the implications of the theory are important for industrial competition strategy and for energy policy. 相似文献
110.
We propose an experiment to observe coherent oscillations in a single quantum dot with the oscillations driven by spin-orbit interaction. This is achieved without spin-polarized leads, and relies on changing the strength of the spin-orbit coupling via an applied gate pulse. We derive an effective model of this system which is formally equivalent to the Jaynes-Cummings model of quantum optics. For parameters relevant to an InGaAs dot, we calculate a Rabi frequency of 2 GHz. 相似文献