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With the help of real-time numerical simulation results, the acquisition properties of a second-order ZC1-DPLL are investigated. Besides confirming the sensitivity of the system dynamics to the initial values of the state variables, it predicts qualitatively the maximum possible frequency acquisition range (FAR) of the system, and obtains the values of the maximum FAR for systems with different design parameters. The effect of jitter on the loop dynamics has also been considered 相似文献
124.
A generalized state-space approach is presented for the steady-state commutation analysis of an autosequential commuted current-source inverter-fed induction motor drive covering all possible modes of operation using a digital computer. The analysis adopts the basic per-phase equivalent circuit for the induction motor model, includes the effect of DC link filter impedance and the variation of back EMF during the commutation interval, and extends the inverter model to cover the complex commutation overlap mode occurring during high frequency operation. A digital computer program is evolved, to identify automatically the relevant sets of equations applicable to a particular mode from a generalized set of equations and to solve them 相似文献
125.
Utpal Chattopadhyay 《Nuclear Physics B》1983,226(2):466-492
Unbroken gauge theories containing light as well as heavy fermions are considered in the limit of the mass of the heavy fermions tending to infinity. The effective coupling constant of the decoupled low-energy theory thus obtained, has been calculated up to two-loop level using the light particle irreducible vertex function and the background field formalism. In addition, to simplify the computation, a background field gauge-fixing term has been used, because in such a gauge the effective coupling constant can be calculated from a two-point function only. Our analysis reveals that in the non-abelian theory, the simple algorithm proposed by Ovrut and Schnitzer for computing the effective coupling constant up to the two-loop level is valid only in the α = 0 or α = ?3 background field gauge. A general procedure correct for all values of α is described. 相似文献
126.
Novel hydrogenolysis of a CC bond linking a benzyl side chain in some octalones is described. 相似文献
127.
An iterative calculation of the warm electron coefficient is presented considering polar mode scattering in a parabolic band. Electron-electron collisions are assumed strong enough to establish a Maxwellian distribution function. The results vary considerably from those of the displaced Maxwellian calculation which has been used earlier for the interpretation of experimental results. 相似文献
128.
High pressure X-ray diffraction study on p-FeS2, m-FeS2 and MnS2 to 340 kbar: A possible high spin-low spin transition in MnS2 总被引:1,自引:0,他引:1
Pyrite p-FeS2, marcasite m-FeS2 and MnS22 have been investigated using the high-pressure X-ray diffraction technique to 340 kbar. MnS2 undergoes a pressure-induced phase transition at about 140 kbar from the pyrite to the marcasite type phase with a volume contraction of about 15%. The high-pressure marcasite type m-MnS2 is found to belong to the B type of marcasite with an axial ratio and p-FeS2 and m-FeS2 do not undergo any phase transition in the pressure range investigated. The high spin p-MnS2 has been found to be much more compressible (Bo = 760 kbar, B′o = 5.4) than the low spin p-FeS2 (Bo = 2154 kbar, B′o = 5.5) and m-FeS2 (B0 = 1465 kbar, B′o = 4.9) while the high-pressure m-MnS2 has comparable compressibility (Bo = 2138 kbar, B′0 = 5.0) with those of low spin p-FeS2 and m-FeS2. The p-MnS2-m-MnS2 phase transition might be accompanied by a high spin-low spin transition of Mn2+. 相似文献
129.
T Chattopadhyay R.P Santandrea H.G Von Schnering 《Journal of Physics and Chemistry of Solids》1985,46(3):351-356
InTe has been investigated using high pressure x-ray diffraction technique to 340 kbar InTe undergoes a pressure induced phase transition from the tetragonal TISe-type (B37) to the NaCl-type (B1) phase We have discovered a further pressure induced phase transition from the NaCl-type to the CsCl type (B2) phase at about 150 kbar The crystal structure of the tetragonal TISe-type InTe has been reinvestigated with x-ray diffractometer data Temperature variation of the lattice constants of the tetragonal InTe has been obtained in the range 297 to 505 K. 相似文献
130.
H. Fjellvåg A. Kjekshus T. Chattopadhyay H.D. Hochheimer W. Hönle H.G. Von Schnering 《Physics letters. A》1985,112(8):411-413
Energy dispersive high-pressure powder X-ray experiments have been performed for MnTe2 up to a pressure of 20 GPa. MnTe2 undergoes a discontinuous transformation from the cubic pyrite type structure to the orthorhombic marcasite type structure at 7.0±0.5 GPa upon increasing pressure. The transformation is accompanied by a large reduction in the specific volume (ΔV/V=0.18) which probably reflects different magnetic properties of the two modifications of MnTe2. 相似文献