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Starting from the extended tree-level model for the πN interaction [1] (hereafter ETLM) we demonstrated that the observed local pion-nucleus repulsion arises from the reduction of baryon masses in nucleus due to strong scalar nuclear field [2]. This is rather convincing argument in favour of nuclear relativism because such repulsion has no explanation within the traditional nonrelativistic approach to nucleus.  相似文献   
74.
In infinite-dimensional Hilbert spaces, we prove that the iterative sequence generated by the extragradient method for solving pseudo-monotone variational inequalities converges weakly to a solution. A class of pseudo-monotone variational inequalities is considered to illustrate the convergent behavior. The result obtained in this note extends some recent results in the literature; especially, it gives a positive answer to a question raised in Khanh (Acta Math Vietnam 41:251–263, 2016).  相似文献   
75.
The Lewis acid-catalyzed addition of cyclic orthoformates to vinyl ethyl ether, which leads to the formation of malonaldehyde acetals, was studied. It is shown that of the linear-cyclic malonaldehyde acetals, 2-(2,2-diethoxyethyl)- and 5,5-dimethyl-2-(2,2-diethoxyethyl)-1,3-dioxanes are stable. The transacetalization of 1,1,3,3-tetraethoxypropane with 1,2- and 1,3-diols, which leads to the formation of cyclic malonaldehyde acetals, was studied. The physicochemical constants of the acetals were determined, and their 1H and 13C NMR spectra are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 459–463, April, 1983.  相似文献   
76.
The dependence of the thermomechanical properties and structure of rapidly quenched Ti49.5Ni25.5Cu25.0 alloy on the annealing conditions has been studied. A sample with a partially ordered structure is found to have two-way shape memory effect during single deformation. An alloy sample 17 × 10 × 0.07 μm in size has been prepared and trained. It is shown to demonstrate two-way shape memory behavior.  相似文献   
77.
The structural-phase state of a copper substrate’s surface layer treated with titanium ions is investigated. It is established via X-ray diffraction analysis that intermetalides of the Cu-Ti type formed in the surface layer following treatment. It is found by means of scanning electron microscopy that a netlike porous structure with characteristic crosswise horizontal and vertical element dimensions of ~1–2 μm forms in the surface layer.  相似文献   
78.
The measurement of the two-mode squeezed vacuum generated in an optical parametric amplifier (OPA) was performed with photon number resolving multipixel photon counters (MPPCs). Implementation of the MPPCs allows for the observation of noise reduction in a broad dynamic range of the OPA gain, which is inaccessible with standard single photon avalanche photodetectors.  相似文献   
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This paper considers various experimental designs on the Atlas facility to study the physics of liners and determine the optimum conditions of their stable motion. In one of the versions, in comparison with the Liner Demonstration series of experiments, in which unstable liner motion was observed, it is proposed to reduce the initial liner radius without changing its mass, which, according to two-dimensional calculations, should to lead to more stable motion of the liner with unchanged velocity. It is also proposed to perform an experiment in which periodic perturbations at a certain wavelength are created on the outer surface of the liner with a simultaneous increase in its thickness. According to calculations, the growth of chaotic perturbations is stabilized in this case with the preservation of the liner velocity. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 3, pp. 3–14, May–June, 2009.  相似文献   
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