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41.
We make predictions for the angular distributions of nucleon-nucleon observables revealing T-violation, in the limit of very short-ranged T-violating mechanisms. Curves are shown for the observables P - a, and PA - PB, at 425 MeV for both p-p and n-p scattering.  相似文献   
42.
A. Gersten   《Nuclear Physics A》1977,290(2):445-459
The helicity amplitudes of the nucleon-nucleon one-photon exchange interaction are calculated. The anomalous magnetic moments of the proton and neutron are included in the calculations. The formalism is especially suitable for the small angle proton-proton interaction at intermediate energies. The electromagnetic phase shifts in the Born approximation are defined and calculated. The three cases of the proton-proton, the neutron-proton and the neutron-neutron interactions are dealt with separately. Analytic expressions are given for sums defined by divergent partial waves. We indicate the pecularities of the neutron-proton interaction: the singlet-triplet transitions and the t−1 singularity in the differential cross section. These peculiarities require an improved treatment of the neutron-proton interaction. A modified formalism is suggested.  相似文献   
43.
Flow and heat transfer along a plane wall with periodic suction   总被引:4,自引:0,他引:4  
Summary The three-dimensional incompressible laminar boundary layer past a flat plate is investigated, when suction with a slightly sinusoidal transverse suction velocity distribution at the wall is applied. For the asymptotic flow conditions far downstream the components of the wall shear stress and the heat transfer including its dependence on Prandtl number are determined.
Zusammenfassung Es wird die dreidimensionale inkompressible, laminare Grenzschicht an der längsangeströmten Platte behandelt, bei der mit einer in Querrichtung schwach sinusförmigen Geschwindigkeitsverteilung an der Wand abgesaugt wird. Für den asymptotischen Zustand weit stromabwärts werden die Komponenten der Wandschubspannung sowie der Wärmeübergang mit dessen Abhängigkeit von der Prandtl-Zahl bestimmt.
  相似文献   
44.
In the presence of an accumulation layer of finite thickness the surface phonons, bulk phonons, and two-dimensional plasmons couple together to form a three-branched surface plasmaron spectrum. Dispersion curves and coupling constants for these plasmarons are evaluated. In the limit of thin accumulation layers one of the modes decouples and a two-mode spectrum emerges. These two modes are admixtures of surface phonons and two-dimensional plasmons.  相似文献   
45.
A. Gersten 《Nuclear Physics A》1974,219(2):317-331
The possibility of reconstructing the scattering amplitude with the aid of the zeros in the complex cos θ plane of the differential cross section is considered. The reconstruction process is demonstrated in two examples. The location of the zeros of the scattering amplitude is examined for the strong absorption and optical models. It appears that there exists a correlation between the position of the zeros and the strength of the absorption.  相似文献   
46.
We examine a recently suggested, novel method for evaluating the contribution of the neutron-proton mass difference to charge-symmetry breaking in then-p system. It is shown that if all terms of first-order in the mass difference are consistently retained the proposal is equivalent to the conventional distorted-wave methods.  相似文献   
47.
One-dimensional particle states are constructed according to orthogonality conditions, without requiring boundary conditions. Free particle states are constructed using Dirac's delta function orthogonality conditions. The states (doublets) depend on two quantum numbers: energy and parity (+ or —). With the aid of projection operators the particles are confined to a constrained region, in a way similar to the action of an infinite well potential. From the resulting overcomplete basis, only the mutually orthogonal states are selected. Four solutions are found, corresponding to different non-commuting Hamiltonians. Their energy eigenstates are labeled with the main quantum number n and parity + or —. The energy eigenvalues are functions of n only. The four cases correspond to different boundary conditions: (I) The wave function vanishes on the boundary (energy levels: l+,2,3+,4,...), (II) the derivative of the wavefunction vanishes on the boundary (energy levels 0+,l,2+,3,...), (III) periodic boundary conditions (energy levels: 0+,2+,2,4+,46+,6,...), (IV) periodic boundary conditions (energy levels: l+,1,3+,3,5+,5,...). Among the four cases, only solution (III) forms a complete basis in the sense that any function in the constrained region, can be expanded with it. By extending the boundaries of the constrained region to infinity, only solution (III) converges uniformly to the free particle states. Orthogonality seems to be a more basic requirement than boundary conditions. By using projection operators, confinement of the particle to a definite region can be achieved in a conceptually simple and unambiguous way, and physical operators can be written so that they act only in the confined region.  相似文献   
48.
New four coordinates are introduced which are related to the usual space-time coordinates. For these coordinates, the Euclidean four-dimensional length squared is equal to the interval squared of the Minkowski space. The Lorentz transformation, for the new coordinates, becomes an SO(4) rotation. New scalars (invariants) are derived. A second approach to the Lorentz transformation is presented. A mixed space is generated by interchanging the notion of time and proper time in inertial frames. Within this approach the Lorentz transformation is a 4-dimensional rotation in an Euclidean space, leading to new possibilities and applications.  相似文献   
49.
We have demonstrated the feasibility of using bacteriophage ghost proteins, tritiated by metabolic labeling, as a set of standard markers for two-dimensional gels in which the proteins are to be detected by silver staining. The results indicate that a 2.5 microgram load of phage proteins yields a reproducible silver pattern of 48 spots. The spots can also be readily identified by radioautography and radiofluorography, establishing their value as a standard constellation of markers. Quantification of these patterns by computerized densitometry indicates a general agreement between detection by silver staining and detection by radiofluorography.  相似文献   
50.
The presence of soluble dextrans, methylcellulose and polyethylene glycol polymers incorporated into vertical sodium dodecyl sulfate (SDS)-polyacrylamide slabs during electrophoresis can have a pronounced effect on protein separations. The effects of various standard and inverse gradients of polymers on the electrophoretic mobility of marker proteins in 10% T, 2.66% C Laemmli-style SDS gels, and the effects of simultaneous pore size and polymer gradients were investigated. These experiments demonstrate that the inclusion of polymers is a new, additional parameter that can be useful in resolving complex mixtures of proteins.  相似文献   
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