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The4He( ,p)n cross section, vector and tensor analyzing-power data with 12 and 17 MeV deuterons at kinematic conditions including proton-alpha quasifree scattering, neutron-alpha and proton-alpha final-state interactions, as well as collinearity, are compared with the predictions of the three-body model using different nucleon-alpha and neutron-proton forces. In general, better two-body potentials give a better fit to the data, except for the vector analyzing-power data. The roles of the impulse and multiple-scattering amplitudes are studied to understand the sensitivity to two-body potentials and to understand the reason for the successes and the failures of the model.  相似文献   
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The operating characteristics of a relativistic 16-vane rising-sun magnetron were investigated with particular emphasis on determining the operating regimes of different modes. The magnetron performance was studied as a function of voltage, magnetic field, cathode geometry, axial boundary conditions, and output coupling. Operation was observed in the 3π/8 mode at 3.3 GHz, in the π/2 or 3π/8 mode at 3.5 GHz, and in the π or 7π/8 mode at 4.6 GHz. A maximum power of 80 MW was emitted in the 3π/8 mode with an efficiency of 4.5%. Typical pulse lengths were 40-50 ns. Cold tests were performed to measure the resonant frequencies and azimuthal electric fields in the interaction space which agreed within 1-4% of theoretical calculations. The operating modes were inferred from close agreement between hot-test frequencies and cold-test results and because high-power RF emission occurred at, or just above, the Buneman-Hartree threshold calculated for these modes. The characteristics of a six-vane A6-magnetron operating in the π and 2π modes were also studied. A unique transmitting-receiving system, which was used as a microwave diagnostic, is described  相似文献   
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High-accuracy analyzing-powerA y() data forn-d elastic scattering at 12 MeV have been measured using the polarized-neutron facilities at the Triangle Universities Nuclear Laboratory (TUNL). The present data have been combined with our previousn-d measurements at 10, 12, and 14.1 MeV to form the highest-accuracyA y() data set forn-d elastic scattering below 20 MeV. These data are compared to recent Faddeev-based neutron-deuteron (n-d) calculations which use the Paris and Bonn equivalent separable potentials PEST and BEST, as well as Doleschall's representation of theP- andD-wave nucleon-nucleon interactions. None of these models adequately describe the data in the angular region around the maximum ofA y(). Possible reasons for the discrepancies are discussed. The sensitivity of the present Faddeev-based calculations to various angular momentum components of the nucleon-nucleon interaction are examined.  相似文献   
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We have phase locked a pair of long-pulse, high-power, secondary-emission magnetrons to an RF-isolated low-power driver via a waveguide directional coupler. With the 3 dB hybrid coupler, the peak and average power sent back towards the driver were lower than the total power by factors of 20 and 100, respectively. A dual-channel, thyratron-switched line-type modulator was used to power the magnetrons in parallel. In this experiment the total microwave power from the pair of phase-locked high-power magnetrons was limited to 48 MW for 700 ns pulses and 46 MW for 900 ns pulses because one of the high-power magnetrons would only operate at or below half power. Experimental results from this repetitively-pulsed (10 Hz) phase-locked magnetron pair are presented which show excellent phase stability of several degrees both during the pulse and from pulse-to-pulse  相似文献   
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Two-spectator quasifree processes (graphs with two spectator particles) for the 3He(3He, dd)pp reaction at the symmetric angle pairs θ = 30.1° at E3He = 50 MeV and θ = 37° at E3He = 78 MeV are investigated. The theoretical cross sections are calculated with the PWIA model. The measured cross sections are smaller but have shapes which are in good agreement with the calculation. The ratio N = experiment/theory is approximately 0.05 at 50 MeV and 0.1 at 78 MeV. The reaction 2H(d, pp)nn also was studied at the symmetric angle pair θ = 34.8° and E2H = 34.7 MeV and the ratio is about 0.14.  相似文献   
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The cross section and the analyzing powers Ay, Axx and Ayy for the reaction 4He(d, αp)n are studied with kinematically complete measurements at incident energies of 12 and 17 MeV. Spectral structures due to the final-state interactions and quasifree scattering are measured. A three-body model of the Faddeev type gives a satisfactory fit to the cross-section and Ay data, but it fails to fit adequately the tensor analyzing-power data. The tensor analyzing powers in the breakup process should be sensitive to the input two-body force, and that sensitivity seems to be somewhat greater near the three-body 1+ resonance.  相似文献   
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Quasifree scattering and quasifree reaction processes have been examined in the 3He+ 2H → p+d+d, 3He + 2H → n+p+3He and 3He+2H → p+p+t reactions. Beam energies of Ed = 22.3 and 35 MeV and of E3He = 30, 33.5, and 52.5 MeV were used. The experimental results are compared with PWIA calculations and Fourier transforms of the wave functions are extracted. The quasifree processes are described qualitatively by the PWIA, but some features cannot be described by either PWIA or DWIA.  相似文献   
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Raman molecular imaging was evaluated as a tool for differentiating between kidney tumors which are sometimes confused using conventional histopathological methods. Renal oncocytoma and chromophobe renal cell carcinoma are two kidney tumors which occasionally possess overlapping histological features. There is no reliable alternative method to routine histologic examination for differentiating these neoplasms. However, a conclusive diagnosis is important, as renal oncocytoma is benign and chromophobe renal cell carcinoma has malignant potential, requiring different treatment options. In an investigation based on 88 patients, a partial least squares discriminant analysis model generated from Raman molecular images distinguished between chromophobe renal cell carcinoma and renal oncocytoma with a performance of 86% sensitivity and 81% specificity. These initial observations suggest that Raman molecular imaging may be applied not only to the differentiation of these kidney tumors but also to other applications for which conventional histological methods are not sufficient for a conclusive diagnosis. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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