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•Experiments show similar ablation craters in Ru caused by different fs light sources.•Absorbed energy localizes near Ru surface due to Auger electrons.•Energy localization causes ...thermo-mechanical ablation via stress confinement.•Damage mechanism at grazing incidence conditions does not depend on photon energy.
We performed combined experimental and computational research on damage processes in ruthenium thin films induced by femtosecond lasers with various photon energies. We present an experiment with an optical laser at normal incidence conditions and compare it with previously reported experiments at grazing incidence conditions with XUV and hard X-ray photons, covering a large range of photon energies. Analysis of ablation craters in Ru shows very similar crater morphology and depth of about 10–20 nm for all considered irradiation conditions. Simulations of light-matter interactions are performed with our combined Monte Carlo and two-temperature hydrodynamics approach. The simulation results show that the primal cause of eventual ablation is Auger decay of core-shell holes created after absorption of XUV and hard X-ray photons in the vicinity of ruthenium surface. They lead to the creation of many low-energy electrons which consequently release the absorbed energy near the surface, resembling the optical irradiation case. Similar absorbed energy distributions in the top part of ruthenium induce a similar thermo-mechanical response and, therefore, similar ablation process. Our results suggest that such mechanism is universal in a wide range of photon energies at grazing incidence conditions, when the photon absorption depth is smaller than the photoelectrons range.
Cold climate regions need railroad ties with improved operational characteristics during the construction and repair of railroad tracks. The aim of the study is to create a technology and equipment ...allowing the manufacture of such sleepers. Low-value soft hardwoods, oily antiseptic, and drying press chamber are needed for the production of sleepers with improved performance characteristics. Technological modes for producing sleepers with high performance characteristics of softwood have been tested using the installation which enables to combine technological operations - drying, treatment, and wood pressing. The resulting sleepers can be used in the Extreme North conditions. The half ties have been laid at Chistye Prudy metro station in Moscow, and the ties have been laid at Scherbenka station on the experimental ring of Russian Railways (JSCo «RZD»). The tests have been carried out for four years in underground railway system and for two years on the ring of Russian Railways. The test results have found that wear of modified sleepers and half ties is about 3 times less than wear of pine sleepers and the average service life of sleepers made of modified wood will be about 50 years. An experimental batch is currently being manufactured.
A universal method of determining the orbits of newly discovered small bodies in the Solar System using their positional observations has been developed. The proposed method suggests determining ...geocentric distances of a small body by means of an exhaustive search for heliocentric orbital planes and subsequent determination of the distance between the observer and the points at which the chosen plane intersects with the vectors pointing to the object. Further, the remaining orbital elements are determined using the classical Gauss method after eliminating those heliocentric distances that have a fortiori low probabilities. The obtained sets of elements are used to determine the rms between the observed and calculated positions. The sets of elements with the least rms are considered to be most probable for newly discovered small bodies. Afterwards, these elements are improved using the differential method.
The effect of Sr by Gd substitution on the structural, thermomechanical, electrical, and electrochemical properties of SrTi
0.5
Fe
0.5
O
3–δ
was investigated in the present work. The powders were ...synthesized by a solid-state reaction method at 1150 °C with following sintering of the ceramic samples at 1350 °C. The unit cell parameters of the sintered Sr
1–
x
Gd
x
Ti
0.5
Fe
0.5
O
3–δ
(
x
= 0–0.4) ceramics were found to decrease with a gradual increase in Gd content, and a change in the crystal symmetry from cubic to tetragonal at
x
≥ 0.1 was observed. It was found that the Gd doping enhanced the stability of the ceramic samples in a reducing atmosphere and reduced the thermal expansion coefficient value. Gd doping in the amount of 5 mol% can be used for long-term stabilization of the SrTi
0.5
Fe
0.5
O
3–δ
material’s conductivity in reducing atmospheres with no significant alteration to the transport properties and oxygen permeability.
The transport and magnetic properties of the Rb
0.8
Fe
1.6
S
2
crystal have been studied under quasihydrostatic compression to a pressure of 40.5 GPa in diamond anvil cells. A semiconductor-semimetal ...electronic transition has been detected at a pressure of about 15 GPa. In addition, the disappearance of the magnetic order down to a temperature of 3 K has been found at a pressure of 24 GPa. It has been shown that, in contrast to a similar selenium compound Rb
0.8
Fe
1.6
Se
2
, superconductivity in Rb
0.8
Fe
1.6
S
2
sulfide does not appear down to the lowest temperatures even at an external pressure of 40.5 GPa.
In the areas of construction materials science, the most promising solution is a set of issues related to the study of the influence of conditions for the formation of the material structure, ...including the possibilities of its self-organization, on its properties. The chemical and physical aspects of this influence are studied at the micro level, using the entire complex of “subtle” studies. At the same time, there are methods that allow us to assess the possibility of nanoeffects in experiments carried out at the macro level: in production or in the laboratory. One of these methods is the method described in the article. The main provisions of the methodology have been formed on the basis of statistical methods for conducting experiments and studying technological processes. This technique can significantly reduce the number of experiments performed while maintaining the adequacy of the results obtained and makes it possible to perform further analytical optimization of the results and their engineering interpretation. In particular, application of this technique allows evaluating joint influence of various factors on the result, that makes it possible to identify synergistic and antagonistic effects and then test them at the micro level by studying the nanostructure of materials. The article, as an example, considers the technology of concrete, focused on the utilization of concrete scrap as a filler or filler in building materials for various purposes. The results of research on the development of composite binder compositions based on fine-ground concrete scrap waste, mineral binder, synthetic fibers and polymers cured as a result of chemical interaction with the components of the concrete mixture are presented. This binder can be used for making various wall elements of buildings.
This paper is a review of current concepts concerning the seismotectonics and seismicity in the Laptev Sea region. The chief feature of the region is a rift system extending in the shelf from the ...continental slope with the adjacent Gakkel Ridge to the mainland coast. There are several models to describe the present-day evolution of the region, but no one of these is preferable because of the lack of local instrumental observations of shelf microseismicity, while such microseismicity is characteristic of rift zones. One alternative approach consists in the installation of ocean bottom seismometers on the shelf itself. During the 73rd cruise of the R/V
Akademik Mstislav Keldysh
, a temporary network was deployed consisting of 7 broadband bottom seismic stations on the Laptev Sea shelf. Comparative analysis of noise spectra based on records of a hydrophone, a bottom seismograph, and a wavegauge, showed that the noise amplitude strongly depends on wind waves, which is in turn dependent on marine ice cover, so that the recording potential of a local network of bottom seismographs is restricted to the winter period of observation.
We report here studies on the cerebral mechanisms of conscious deceptive and honest manipulative actions. Analysis of cause-effect relationships showed that the execution of both deceptive and honest ...actions with the aim of manipulating the opinion of an opponent was characterized by a bottom-up interaction between components of the frontostriate system: the caudate nuclei modulated the activity of the prefrontal cortex. This result confirms the hypothesis that the cerebral error detection (ED) mechanism is involved in selection of the appropriate version of an action during execution of manipulative actions.
Effect of magnesium on the sinterability, phase composition, microstructure, and transport properties of proton-conducting materials of composition LaY
1–
x
Mg
x
O
3–δ
(
х
= 0, 0.05, 0.1) was ...studied. Ceramic samples were obtained by using the citrate-nitrate synthesis method at various sintering temperatures (1250–1400°C). It was shown that, for the samples with
x
= 0.05 and 0.1, the relative density was no less than 95% at a sintering temperature of 1350°C, whereas undoped lanthanum nitrate has this density at 1450°C. An X-ray diffraction analysis and scanning electron microscopy demonstrated that introduction of a small amount of magnesium (
x
= 0.05) is sufficient for forming the single-phase and high-dense ceramics. Electrical conductivity data show that the LaY
0.95
Mg
0.05
O
3–δ
sample has high overall and ionic conductivities.
•We compare single vs. dual system models of inflectional morphology using fMRI.•Previous neuroimaging studies rely mostly on English and German, we use Russian.•This is the first fMRI study of ...Russian morphology, verbs and nouns are analyzed.•Our findings are more readily compatible with the single-system approach•We suggest a processing load explanation for observed activation patterns.
The generation of regular and irregular past tense verbs has long been a testing ground for different models of inflection in the mental lexicon. Behavioral studies examined a variety of languages, but neuroimaging studies rely almost exclusively on English and German data. In our fMRI experiment, participants inflected Russian verbs and nouns of different types and corresponding nonce stimuli. Irregular real and nonce verbs activated inferior frontal and inferior parietal regions more than regular verbs did, while no areas were more activated in the opposite comparison. We explain this activation pattern by increasing processing load: a parametric contrast revealed that these regions are also more activated for nonce stimuli compared to real stimuli. A very similar pattern is found for nouns. Unlike most previously obtained results, our findings are more readily compatible with the single-system approach to inflection, which does not postulate a categorical difference between regular and irregular forms.
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