The Small-angle X-Ray Scattering Investigation of Advanced Beryllium Materials

The small-angle X-ray scattering (SAXS) technique allows to determine size distributions of inhomogeneities in materials and to predict their properties in Xray optics devices. A number of beryllium materials for the manufacturing of X-ray optics (refractive lenses and speckle suppressors) have been studied by the SAXS.Various composite materials based on porous beryllium have been studied. The effect of adding detonation nanodiamonds to the beryllium matrix on the scattering ability of the material is discussed. Keywords: porous beryllium, SAXS, detonation nanodiamonds, speckle-suppresso

Formation of professional competences of bachelors in the execution of final qualification work

The aim of this article is to provide a modern level of development of economic and organizational issues in the final qualifying works for preparation of bachelors vocational training specialization «Technology and equipment of mechanical engineering» and formation of the appropriate competencies. The maximum approximation of the educational environment to the conditions of the real production will allow to carry out the competence of practice-oriented approach in the training of highly qualified specialists for the Russian machinebuilding.Целью данной статьи является обеспечение современного уровня разработки экономических и организационных вопросов в ВКР при подготовке бакалавров профессионального обучения профилизации «Технологии и оборудование машиностроения» и формирование соответствующих компетенций. Максимальное приближение образовательной среды к условиям реального производства позволит осуществить компетентностный практико-ориентированный подход в подготовке высококвалифицированных специалистов для российского машиностроения

Formation and Study of Properties of Ta and Mo Nanocluster Films

In this article, the results of studies of thin-film samples of nanoclusters of tantalum and molybdenum metals on the surface of silicon dioxide SiO2 /Si (001) at room temperature are presented. The chemical composition and electronic structure of the obtained nanocluster films of Ta and Mo were controlled in situ by X-ray photoelectron spectroscopy (XPS). Susceptibility to oxidation during the exposure to the atmosphere of then nanocluster films, as well as their thermal stability when heated in a vacuum to 600∘C were studied ex situ by the XPS method. The size and shape of the nanoclusters composing the film were estimated ex situ by analyzing images obtained with a scanning electron microscope. The band structure before and after oxidation was studied by measuring the bandgap of the formed Ta and Mo films by the method of electron energy loss characteristic spectroscopy (REELS). Conclusions about thermoelectric properties of the formed nanocluster films of Ta and Mo were made

Mapping of multiple muscles with transcranial magnetic stimulation: Absolute and relative test-retest reliability

The spatial accuracy of transcranial magnetic stimulation (TMS) may be as small as a few millimeters. Despite such great potential, navigated TMS (nTMS) mapping is still underused for the assessment of motor plasticity, particularly in clinical settings. Here, we investigate the within‐limb somatotopy gradient as well as absolute and relative reliability of three hand muscle cortical representations (MCRs) using a comprehensive grid‐based sulcus‐informed nTMS motor mapping. We enrolled 22 young healthy male volunteers. Two nTMS mapping sessions were separated by 5–10 days. Motor evoked potentials were obtained from abductor pollicis brevis (APB), abductor digiti minimi, and extensor digitorum communis. In addition to individual MRI‐based analysis, we studied normalized MNI MCRs. For the reliability assessment, we calculated intraclass correlation and the smallest detectable change. Our results revealed a somatotopy gradient reflected by APB MCR having the most lateral location. Reliability analysis showed that the commonly used metrics of MCRs, such as areas, volumes, centers of gravity (COGs), and hotspots had a high relative and low absolute reliability for all three muscles. For within‐limb TMS somatotopy, the most common metrics such as the shifts between MCR COGs and hotspots had poor relative reliability. However, overlaps between different muscle MCRs were highly reliable. We, thus, provide novel evidence that inter‐muscle MCR interaction can be reliably traced using MCR overlaps while shifts between the COGs and hotspots of different MCRs are not suitable for this purpose. Our results have implications for the interpretation of nTMS motor mapping results in healthy subjects and patients with neurological conditions