Antiproton Production in p+d Reaction at Subthreshold Energies

An enhancement of antiprotons produced in p+d reaction in comparison with ones in p+p elementary reaction is investigated. In the neighborhood of subthreshold energy the enhancement is caused by the difference of available energies for antiproton production. The cross section in p+d reaction, on the other hand, becomes just twice of the one in elementary p+p reaction at the incident energy far from the threshold energy when non-nucleonic components in deuteron target are not considered.Comment: LaTeX,7 pages with 5 eps figure

Volume, Coulomb, and volume-symmetry coefficients of nucleus incompressibility in the relativistic mean field theory with the excluded volume effects

The relation among the volume coefficient $K$(=incompressibility of the nuclear matter), the Coulomb coefficient $K_c$, and the volume-symmetry coefficient $K_{vs}$ of the nucleus incompressibility are studied in the framework of the relativistic mean field theory with the excluded volume effects of the nucleons, under the assumption of the scaling model. It is found that $K= 300\pm 50$MeV is necessary to account for the empirical values of $K$, $K_c$, and $K_{vs}$, simultaneously, as is in the case of the point-like nucleons. The result is independent on the detail descriptions of the potential of the $\sigma$-meson self-interaction and is almost independent on the excluded volume of the nucleons.Comment: PACS numbers, 21.65.+f, 21.30.+

Compressional properties of nuclear matter in the relativistic mean field theory with the excluded volume effects

Compressional properties of nuclear matter are studied by using the mean field theory with the excluded volume effects of the nucleons. It is found that the excluded volume effects make it possible to fit the empirical data of the Coulomb coefficient $K_{c}$ of nucleus incompressibility, even if the volume coefficient $K$ is small($\sim 150$MeV). However, the symmetry properties favor $K=300\pm 50$MeV as in the cases of the mean field theory of point-like nucleons.Comment: PACS numbers, 21.65.+f, 21.30.+

Equivalent Young’s Modulus of the Spiral Accumulating Motor Core Including Many Slits and Embossing Interlockings

The motor core is usually manufactured from magnetic steel sheet with press machine. However, usually most parts of the plate are scalped, and only small percent of the sheet is used for the core. The spiral accumulating core system is suitable for manufacturing the core more ecologically because in this system more than 50% of the magnetic steel sheet can be used. However, since the spiral accumulating core has many slits and embossing interlockings, the equivalent Young\u27s modulus is not known. In this study, therefore, the equivalent Young\u27s modulus of the spiral accumulating core is considered in order to find out a good method to fix the core. Here, the finite element method is applied to analyze the permanent magnet motor core, whose layers and slits are periodically arranged. Then, the effects of slits, layers and embossing interlockings on equivalent Young\u27s modulus are discussed. It is found that around the slits the core layer should be considered to have zero elastic modulus because no tangential stress exists. Finally, a convenient method of calculation based on rule of mixture is newly proposed to estimate the equivalent Young\u27s modulus efficiently.11th International Conference on the mechanical behavior of Materials (ICM11), 5-9 June 2011, Como, Ital

Stress intensity factor for multiple inclined or curved cracks problem in circular positions in plane elasticity

The problems of multiple inclined or curved cracks in circular positions is treated by using the hypersingular integral equation method. The cracks center are placed at the edge of a virtual circle with radius R. The first crack is fixed on the x-axis while the second crack is located on the boundary of a circle with the varying angle, θ. A system of hypersingular integral equations is formulated and solved numerically for the stress intensity factor (SIF). Numerical examples demonstrate the effect of interaction between two cracks in circular positions are given. It is found that, the severity at the second crack tips are significant when the ratio length of the second to the first crack is small and it is placed at a small angle of θ

Experimental verification of the coming out of the shaft for the ceramic rolls/rollers with shrink fitting system

Ceramic rolls/rollers have an advantage in steel strip production because of its high wear resistance and corrosion resistance. The new rolls/rollers consist of a ceramic sleeve and two alloyed steel shafts connected to the sleeve ends only under a small shrink fitting ratio because of the brittleness. However, the alloyed steel shafts may be loosening out from the ceramic sleeve under such low shrink fitting ratio. In the some previous studies have considered the coming out mechanism was considered by the numerical simulation focusing on the displacement and the shear stress at the joint end. This phenomenon should be confirmed without experiment. In this study, therefore, in order to clarify the coming out behavior, rotating bending experiment is conducted for a small roller specimen consisting of a steel sleeve and steel shafts connected by low shrink fitting ratio. Then, it is found that the coming out can be realized in the small specimen.6th International Conference on Fracture Fatigue and Wear, 26–27 July 2017, Porto, Portuga