共查询到20条相似文献,搜索用时 203 毫秒
1.
讨论了银道面内的引力场强分布和太阳在银河系中所受引力与到银心距离r的关系,指出引力场强g并不是与r的平方成反比,这是由于银河系的大小和形状不能忽略造成的.强调了万有引力定律的适用条件. 相似文献
2.
R. A. Vadov 《Acoustical Physics》2005,51(3):265-270
The disagreement between the experimental and calculated positions of the first convergence zone are known from many publications. The most probable cause for such a disagreement, namely, the incorrect specification of the input data for the calculations, is considered. The lack of simultaneity between the hydrological surveys of the region and the acoustic experiments is emphasized. The experimental data obtained by the author in five ocean regions are presented. These data characterize the diurnal variability of the distance from the source to the nearest boundary of the convergence zone. The relations proposed by different researchers for calculating the sound speed from the temperature, salinity, and hydrostatic pressure are analyzed. It is shown that these relations lead to a substantial difference in the estimated depth dependence of the hydrostatic gradient of the sound speed. The position of the first convergence zone is calculated for the propagation conditions determined by vertical temperature and salinity profiles with the subsequent recalculation of these profiles into sound speed profiles by using eight different formulas known from the literature. It is shown that different formulas lead to different values of the distance to the first zone; this difference is substantially greater than that between the calculations and experiment. The necessity of improving the recalculation relations in view of the experimental data on sound propagation in natural oceanic waveguides, including the data on the actual positions of the convergence zones, is emphasized. 相似文献
3.
Design and analysis of the tunnel connecting the beamcorridor and the spectrum hall of the CSNS
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There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project.The length of the tunnel is about 20 m.The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered ed soil for shielding.In order to reduce the dose rate at the exit of the cable ducts,we use the ISIS construction,which is designed with four turnings,as a reference for the tunnel design.The thickness of the shielding is obtained by a simulationwith the Monte Carlo Code FLUKA.The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved.This paper provides the basis for the design of the tunnel. 相似文献
4.
Design and analysis of the tunnel connecting the beamcorridor and the spectrum hall of the CSNS 总被引:1,自引:0,他引:1
There is a tunnel connecting the beamcorridor and the target station in the spectrum hall in the CSNS project. The length of the tunnel is about 20 m. The shielding design of the tunnel is very significant for the persons working in the spectrum hall because the tunnel is not covered by soil for shielding. In order to reduce the dose rate at the exit of the cable ducts, we use the ISIS construction, which is designed with four turnings, as a reference for the tunnel design. The thickness of the shielding is obtained by a simulation with the Monte Carlo Code FLUKA. The result is compared with the data obtained with Moyer Mode and the reliability of the simulation is proved. This paper provides the basis for the design of the tunnel. 相似文献
5.
Toyoki Koga 《International Journal of Theoretical Physics》1975,12(3):205-215
The conventional interpretation of the spin matrices contained in the Dirac equation for the electron is considered to be mostly unintelligible in the operational sense. It is shown that it appears that the interpretation is often illogical. The necessity of a more comprehensible interpretation of the concerned equation is implied. 相似文献
6.
A comprehensive analysis of the application of the method of collective coordinates to the two dimensional Higgs model is given. First the instanton solution is derived, and the geometry of configuration space, and the construction of Schrodinger wave functionals are discussed. It is then explicitly verified that the Goldstone mode is the projection of the vacuum state onto the generator of the broken symmetry. The elimination of this Goldstone mode by means of the unitary gauge condition is demonstrated to the the crucial point in the construction of a consistent perturbation procedure. The parameter of the broken symmetry group is then used as the collective coordinate for field configurations around a minimum of the interaction. Throughout, the discussion is sufficiently detailed in order to facilitate the application of the method to other fields. 相似文献
7.
A. G. Beda V. B. Brudanin E. V. Demidova V. G. Egorov M. G. Gavrilov V. N. Kornoukhov A. S. Starostin C. Vylov 《Physics of Atomic Nuclei》2004,67(11):1948-1952
The investigation of the background structure of the spectrometer GEMMA was carried out in a low-background laboratory in ITEP. GEMMA is destined for measurement of the neutrino magnetic moment near the core of a nuclear power plant (NPP) reactor. The results of the investigation in ITEP and measurement of the background in the experimental hall at the Kalininskaya NPP proved that GEMMA is ready for the start of the experiment at the reactor. Now the preparation of the experimental hall for the measurement is completed and an assembling of the setup is in progress. 相似文献
8.
V. A. Shvets 《Optics and Spectroscopy》2017,123(2):300-304
A method for measuring the phase of the reflection coefficient in the optical wavelength range is proposed. The method is simple in experimental implementation and is based on measuring the energyreflection coefficients of a sample in two media with different refractive indices. Analytical and numerical estimates show that the measurement accuracy of the phase is on the order of 1°. The possibilities of using the results of the phase measurement in practice for a more complete characterization of materials and structures under investigation are considered. 相似文献
9.
J. Šlechta 《Czechoslovak Journal of Physics》1968,18(10):1299-1308
On the basis of the classical theory of radiation produced in incomplete Coulomb interaction, a formula is derived for the coefficient of the bremsstrahlung of fully ionized plasma. In the region of rectilinear approximation a comparison is made with the results of the quantum formula derived from the Born approximation. Furthermore, the influence of dispersion upon the emission coefficient is taken into account; some relations for the region of dispersion are given. 相似文献
10.
A method of determining the exact solutions to the Burgers equation on the basis of the Darboux transformation is described.
It is shown that a single application of the Darboux transformation to the homogeneous Burgers equation transforms the latter
into the inhomogeneous equation describing acoustic wave propagation against transonic flow in the de Laval nozzle. In this
case, the contraction ratio of the nozzle is fixed and determined by the viscosity coefficient of the medium. Based on the
exact solution of the homogeneous Burgers equation, for the aforementioned problem of the flow in the nozzle, all the possible
regular steady-state solutions are presented and the evolution of nonstationary solutions is investigated. The algorithm of
a multiple Darboux transformation, which allows an increase in the strength of inhomogeneity, i.e., in the contraction ratio
of the nozzle, is determined. This approach leads to a discrete set of possible contraction ratios at which exact solutions
can be obtained. The Crum’s theorem is used to derive a formula that allows determination of the exact solutions to the inhomogeneous
Burgers equation from the solutions to the homogeneous heat transfer equation. It is noted that, in fact, the proposed algorithm
of the multiple Darboux transformation makes it possible to decrease the viscosity coefficient of the medium in a discrete
way. 相似文献
11.
We consider as in [1] an infinite dynamical system idealized as aC*-algebra acted upon by time-translation automorphisms. We show that a stationary state of such a system which is stable for local perturbations of the dynamics and is clustering in time, either gives rise to a one-sided energy spectrum or is a KMS state. The clustering property assumed here is weaker than the one assumed in [1]. The new proof makes explicit use of spectral properties of clustering states.Supported by the Norwegian Research Council for Science and Humanities. 相似文献
12.
R. Brout 《Foundations of Physics》1987,17(6):603-619
Time arises in the theory of gravity through the semiclassical approximation of the gravitational part of the solution of the Wheeler-De Witt equation in the manner shown by Banks (SCAG). We generalize Banks' procedure by grafting a Born-Oppenheimer type approximation onto SCAG. This allows for the feedback of matter onto gravity, wherein the latter is driven by the (quantum) mean energy-momentum tensor of matter. The wave function is nonvanishing in classically forbidden configurations of gravity. In SCAG this is described by the evolution of matter in imaginary time. This is interpreted as an inverse temperature, and the norm of the matter wave function, no longer conserved for these gravitational configurations, is a partition function. A simple cosmological model is worked out to illustrate these ideas. In this model it is shown that the temperature of the matter which emerges into the classically permitted region is the inverse bounce time of the bounce executed by the system in the forbidden region (behind the horizon).Time present and time past are both perhaps present in time future. And time future contained in time past. If all time is eternally present All time is unredeemable.—T. S. Eliot, Burnt Norton,Four Quartets, 1943.In honor of Ilya Prigogine on the occasion of his 70th birthday. 相似文献
13.
14.
通过对欧姆表原理的分析,发现它相当于一个内电阻可变的电源,结合二极管的伏安特性曲线,可解释用欧姆表的不同量程测同一二极管得到的电阻值不同的问题. 相似文献
15.
16.
Wolfdieter Lang 《Nuclear Physics B》1981,179(1):106-128
The superspace analogue of the improved energy-momentum tensor is analysed. The supercurrent of Ferrara and Zumino is derived from the superspace-translation tensor in its minimal form. The additional freedom in this tensor, as compared to the supercurrent, is exhibited. 相似文献
17.
18.
Sian M Stumbles 《Annals of Physics》1984,157(1):101-139
A new way of showing local positivity of the Bondi mass is presented. The method used makes use only of the constraint equations. By looking at the constraint equations of general relativity on an asymptotically constant mean extrisic curvature hypersurface, a mass aspect is picked out, whose average over the 2-sphere coincides with the Bondi mass. This mass aspect differs from Bondi's mass aspect by terms linear in the news function. It is shown that the mass aspect so produced may be considered as a functional of the dependent data in the problem. This functional is shown to have Minkowski space as a critical point. The second variational of the functional about flat space is then shown to be positive. From this, one concludes that the functional is positive in a neighborhood of flat space. Hence the Bondi mass, too, is positive in a neighborhood of flat space. 相似文献
19.
A. Igarashi L. Gulyás P. D. Fainstein 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(1):73-77
The continuum distorted-wave model with an eikonal initial state for
ionisation is discussed within the framework of the impact-parameter
method. Particular attention is paid to the surface term, which
describes the transition by a distorting potential, and which has been
omitted in all of the previous calculations performed using the model.
However, this term is included in the transition amplitude in a recent
application of the model based upon a quantum-mechanical treatment. The
present study, in which the surface term is evaluated within the
impact-parameter method, shows that this term does not contribute to the
transition amplitude. In describing the electron-ejection mechanism for
a p±–H collision, the cross-sections evaluated using the
impact-parameter model show numerical agreement with those determined in
the quantum-mechanical version. This agreement indicates that the
contribution of the surface term calculated in the wave treatment
is negligible over the region in which the impact-parameter model is
valid. 相似文献
20.
A method of calculation is presented for the yield of an electron excitation process by a channelled particle in a single encounter with an atomic row or plane in a crystal. It is shown that, if ψ is the initial angle between the ion trajectory and the row or plane, the number of inner-shell electrons excited is an increasing function of ψ whereas the number of outer electrons excited may decrease with increasing ψ. 相似文献