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51.
D. Gold C. Bonet G. Chauvin A. C. Mathieu G. Geirnaert J. Millet 《Plasma Chemistry and Plasma Processing》1981,1(2):161-178
A 100-kW three-phase ac plasma furnace with sheathed copper electrodes (sheathing gas: air) is presented. It is used for spheroidizing chamotte (refractory-fired clay) particles having a smooth, pore-free surface. A simple, one-dimensional numerical model for the heat transfer to the particles explains the maximum processing rate and the detrimental influence of an inhomogeneous particle size distribution. 相似文献
52.
Bela Gold 《The Journal of the Operational Research Society》1965,16(3):287-307
Productivity analyses have been undertaken by such a variety of specialists and in such differing contexts that few can cope with the broadly dispersed literature. It is not surprising, therefore, that the same problems are rediscovered time and again, that faulty concepts remain in use and that empirical findings are often misinterpreted. Such shortcomings will continue to hamper the development of this field until past advances are more effectively consolidated and the current frontiers more clearly delineated. In this paper, therefore, certain past findings will be used as points of departure for considering the problems and means of effecting further gains.One comprehensive exploration of productivity analysis suggested four general conclusions, along with their analytical foundations, which seem to have withstood subsequent consideration well enough to serve as bases for this undertaking: Such conclusions imply that productivity adjustments may assume many forms, that apparent increases in productivity levels need not always be beneficial, that the very same pattern of productivity changes may have quite different effects in dissimilar circumstances and, finally, that productivity increases are not ends in themselves but merely one means of promoting more fundamental ends. Further development may seek to extend the original analysis beyond standardized commodity production to other economic activities, beyond a plant or firm to larger aggregates, and beyond short periods. But such elaborations of this framework require the strengthening of its conceptual foundations. Hence, it is to these that primary attention will be given. 相似文献
- 1)That productivity analysis serves a variety of purposes and hence requires a corresponding variety of appropriately designed measures:
- 2)That the productivity of any activity system should refer not to any single input-output ratio, but to an integrated network of such measures;
- 3)That the effects of productivity adjustments depend not only on their magnitudes, but also on the sources responsible for them, on the nature of the changes in input-output relationships involved, and on managerial choices among alternative means of harnessing their potential benefits;
- 4)That evaluating such effects requires supplementing physical with cost measures and then with successively broader criteria until these come to reflect the guiding objectives of the system under study.
53.
Gold S.H. Fliflet A.W. Manheimer W.M. McCowan R.B. Lee R.C. Granatstein V.L. Hardesty D.L. Kinkead A.K. Sucy M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1988,16(2):142-148
A K a-band gyrotron oscillator powered by a compact pulseline accelerator has been operated using oscillator cavities with and without axial slots. The oscillator was operated at high voltage (~900 keV) and high current (~500 A) in the approximate frequency range of 20-50 GHz. The use of axial slots has been shown to suppress low-starting-current whispering-gallery modes, in particular, modes of the TEm2 type, allowing stable operation in a linearly polarized TE13 mode. A peak power of 35 MW has been observed at 6% efficiency 相似文献
54.
ABHYANKAR 's Lemma provides a simple method of producing unramified extensions of number fields. By application of the lemma we simultaneously simplify and strengthen some recent results of ISHIDA concerning unramified abelian extensions and class numbers. 相似文献
55.
The vibration-rotation spectrum of methyl isocyanide (CH3NC) has been recorded with the aid of a high-resolution Fourier transform spectrometer in the region 1370 to 1560 cm−1 containing the perpendicular band of the fundamental vibration ν6 (species E), the weaker parallel band of the ν3 (A1) fundamental, and the perpendicular combination band ν7 + ν8 (E) enhanced by Fermi resonance with ν6. Sixteen hundred seventy well-resolved lines were assigned to 15 subbands of ν6, 6 subbands of ν3, and 3 subbands of ν−7 + ν−8. A strong x, y-Coriolis resonance between ν3 and ν6 and Fermi resonance between ν±6 and the E component ν7 + ν8, as well as between ν3 and the A1,2 components ν±7 + ν8, greatly affects the spectrum. Additional weaker anharmonic interaction of ν6 with the ν4 + 2ν28 combination and higher-order rotational interactions connecting the various states were also detected in the spectrum. All of these interactions have been incorporated into a 9 × 9 Hamiltonian matrix used for modeling the upper states of the observed transitions. A set of spectroscopic constants is reported for the upper states of the bands ν3, ν6, and ν7 + ν8 and for ν4 + 2ν28 which reproduces the observed lines with an overall standard deviation of 0.0012 cm−1. 相似文献
56.
Measured dynamical conductivities in accumulation layers doped with Na+ on (100)-Si are reported and analyzed with a theory of a strongly disturbed two-dimensional interacting electron gas and explained in terms of localization-and screening breakdown effects. 相似文献
57.
Cepstral processing techniques in principle allow the separation of superposed pulses, such as those which occur in acoustic reflection, where a reflected pulse is a delayed and distorted version of the incident pulse. Additionally, the impulse response of the reflecting system, or equivalently its reflection coefficient, can also be determined. In practice, the accurate extraction of the impulse response is rendered difficult by the mathematical and computational properties of the power cepstrum procedure. In particular, spectral irregularity of the incident pulse, experimental noise and cepstral aliasing can cause the impulse response in the cepstrum to be masked. However, by careful selection of the incident signal, anti-aliasing filter, sampling frequency and echo delay in relation to the total sampling time, and the use of signal processing techniques such as time domain averaging, recursive filtering in the cepstral domain and zero padding, it is possible to produce good quality cepstra in which the reflector impulse response appears as an isolated feature. Experiments conducted on an electrical analogue of the acoustical reflection process have allowed the cepstral technique to be developed and evaluated. The acoustical reflector is simulated by a passive electrical filter network; the objective of the measurement and subsequent processing is the determination of the transfer function of this network. Good agreement is obtained between theoritical and measured transfer functions for a variety of filter networks indicating that cepstral techniques may be useful for acoustical reflection measurements given adequate transducer properties and environmental conditions. 相似文献
58.
Voutchkova AM Appelhans LN Chianese AR Crabtree RH 《Journal of the American Chemical Society》2005,127(50):17624-17625
N,N'-Disubstituted imidazolium-2-carboxylates are efficient precursors to NHC complexes of Rh, Ir, Pd, and Ru. 相似文献
59.
Lisa J. Hilliard D.Steven Foulk Harvey S. Gold Carl E. Rechsteiner 《Analytica chimica acta》1981,133(3):319-327
Ultraviolet-visible and fluorescence spectra have long been utilized for qualitative and quantitative purposes despite numerous complicating factors. In this study, anthracene, 1-naphthol, and 9-acetylanthracene are used as model systems to distinguish solventinduced effects via multiple regression techniques. The ability to predict changes in spectral peak locations and quantum efficiencies arising from solute—solvent interactions is critical to the development of a versatile computer-searchable library of electronic spectra. 相似文献
60.
The rate coefficients for the reactions of Cl atoms with CH3Br, (k1) and CH2Br2, (k2) were measured as functions of temperature by generating Cl atoms via 308 nm laser photolysis of Cl2 and measuring their temporal profiles via resonance fluorescence detection. The measured rate coefficients were: k1 = (1.55 ± 0.18) × 10?11 exp{(?1070 ± 50)/T} and k2 = (6.37 ± 0.55) × 10?12 exp{(?810 ± 50)/T} cm3 molecule?1 s?1. The possible interference of the reaction of CH2Br product with Cl2 in the measurement of k1 was assessed from the temporal profiles of Cl at high concentrations of Cl2 at 298 K. The rate coefficient at 298 K for the CH2Br + Cl2 reaction was derived to be (5.36 ± 0.56) × 10?13 cm3 molecule?1 s?1. Based on the values of k1 and k2, it is deduced that global atmospheric lifetimes for CH3Br and CH2Br2 are unlikely to be affected by loss via reaction with Cl atoms. In the marine boundary layer, the loss via reaction (1) may be significant if the Cl concentrations are high. If found to be true, the contribution from oceans to the overall CH3Br budget may be less than what is currently assumed. © 1994 John Wiley & Sons, Inc. 相似文献