Special features of structural and phase transformations, position of critical points, quantitative parameters of the structure, and hardness under continuous transformation of supercooled austenite ...in steels 30KhNMFRA, 30KhGNMFRA and 30KhN3MFRA are determined. Thermokinetic diagrams of decomposition of supercooled austenite in the steels are plotted using a Gleeble 3500 research complex. Recommendations are developed for selection of chemical composition and cooling rate for billets in order to provide a high strength and enough impact toughness of the steels after quenching and low tempering. The results may be used for development of high-strength cold-resistant steels and modes of their heat hardening.
The combined unit is used for tillage and subsurface belt application of protective and stimulating liquids and microorganisms into the soil. New technology offers for the task to use pneumatic ...slotted sprayers with jet-forming device that is linked with a compressor that delivers air to transform the operation fluid from the tank in the aerial-droplet jet processing lower layers of the soil simultaneously with cultivation. Protective shields save the sprayer from deformation and breakage. To obtain the required range of the jet, the angle of inclination of the sprayer is adjusted. The supply line of operation fluid has an equalizing capacity to change the flow rate of the operation fluid. The basis of the development of sprayers was the task of development of a plane-parallel jet capable of spreading to a distance to 2 m with an adjustable width of a grip m/s. there were conducted the researches of performance (charge) of pneumatic slotted sprayer depending on air pressure given to in slotted nozzles of the sprayer.
The first results are presented for observations of the VLF emissions (1–15 kHz) conducted at polar latitudes during the expedition Transarctica 2019, which was organized by the Arctic and Antarctic ...Research Institute. The observations were conducted onboard the Akademik Treshnikov vessel with highly sensitive equipment developed at the Polar Geophysical Institute. Bursts of the VLF emission of the auroral hiss type were registered on 13 of the 26 observational days. These bursts were simultaneously observed at Barentsburg Observatory, which is ~600 km to the west and ~160 km to the south. However, these bursts were not registered at lower auroral latitudes at the same meridian at Lovozero Observatory or at a Finnish station, Kannuslehto. One of the most typical cases, the auroral VLF hiss of April 11, 2019, is considered in detail. It is concluded that the region of the exit of the studied auroral hiss from the ionosphere to the Earth’s surface was local and limited in latitude.
Creation of a delivery system based on noncontact positioning and transport of the cryogenic fuel targets represents one of the major tasks in a general program of inertial fusion energy (IFE) ...research. The purpose is to maintain the fuel layer quality during acceleration and injection of IFE targets at the focus of a powerful laser facility or IFE reactor. The program of the Lebedev Physical Institute (LPI) includes much development work on creation of different designs of the hybrid accelerators for IFE target transport with levitation. One of the main directions is an electromagnetic accelerator (EM-AC) + PMG system, where PMG is the permanent magnet guideway. The operational principle is based on quantum levitation of type-II high-temperature superconductors (HTSC) in the magnetic field. At the current stage, conceptual development of “EM-AC + PMG” hybrid accelerator is complete, and proof-of-principle experiments in mutually normal magnetic fields are made. This accelerator is a combination of the acceleration system (field coils generating the traveling magnetic waves) and the levitation system (PMG including a magnetic rail or magnetic track). The results obtained show that the HTSCs can be successfully used to maintain friction-free motion of HTSC sabots over the PMG, and also provide the required stability of the levitation height over the whole acceleration length due to the pinning effect. Additionally, using the driving body from MgB
2
superconducting coils as a sabot component (critical current 5,000 A at magnetic induction 0.25 T) allows one to reach injection velocities of 200 m/s under 400
g
at 5 m acceleration length.
This paper discusses the spectral and temporal features of the 7-h daytime VLF noise emission burst in the frequency band of 1‒10 kHz observed on the Earth’s surface during the late recovery phase of ...a moderate magnetic storm (
Kр
= 5 and
Dst
~ –80 nT) under nearly quiet space weather. These VLF emissions were recorded simultaneously at two auroral stations located at a geomagnetic latitude of ~64° MLAT and at a longitude distance of ~400 km from each other: Finnish Kannuslehto Station (KAN) and Russian Lovozero Observatory (LOZ). The dynamic VLF wave spectrum is considered at different time scales. During the development of the discussed daytime VLF burst, the noise emissions at below 3.5 kHz gradually turn into periodic (
QP
) emissions with a quasi-repetition of ~3 s. Having compared the directions of short isolated high-frequency (above 5 kHz) VLF signals (so-called “birds”) arriving at KAN and LOZ, we draw conclusions on the possible location and spatial dynamics of the exit area of emission from the ionosphere.
Hypertrophic cardiomyopathy is a common genetic heart disease characterized predominantly by non-dilated hypertrophy of the left ventricle, in the absence of other cardiac, systemic, or metabolic ...diseases that can cause the observed degree of hypertrophy. The main features of left ventricular outflow tract obstruction include anatomical - basal septal hypertrophy in combination with a relatively small left ventricular cavity, leading to a change in the geometry of the outflow tract from the left ventricle, pushing the mitral valve apparatus forward, and functional - systolic anterior motion of elongated mitral valve leaflets with subsequent mitral-septal contact. Primary anatomical changes of the mitral valve make the valve more susceptible to abnormal flow vectors generated in the left ventricle cavity, creating the conditions for systolic anterior motion and mitral regurgitation. Septal myectomy, performed by experienced surgeons in specialized centers, eliminates obstruction at all levels of the left ventricular outflow tract, with a clinical success rate of 90-95% and a mortality rate of less than 1%. Some surgeons complement septal myectomy with intervention on the mitral valve, taking into account anatomical features when isolated septal myectomy may be ineffective. The choice of the most optimal concurrent intervention on the mitral valve during septal myectomy is undefined. Techniques for valve-sparing mitral valve surgery have been developed, including resection of secondary chords, edge-to-edge repair, anterior leaflet plication, and others. This review presents the hemodynamic outcomes of concomitant interventions on the mitral valve in addition to septal myectomy in patients with obstructive hypertrophic cardiomyopathy.
Users, while developing and executing their applications, can choose from several supercomputer systems to get computation results. This choice is influenced by many factors, and the wait time before ...application execution is among them, because users can not immediately get the required resources which are allocated for computing the results of other users’ computational jobs. Special software, called schedulers, is used to manage and share resources. Although schedulers use fixed algorithms for this task, the queue wait time is often difficult to estimate, because of the lack of information about jobs and future events. In this research, different methods of job queue wait time estimation are compared, some algorithms are modified and evaluated, using execution logs of the ‘‘Lomonosov-2’’ supercomputer.
The relevance of the study of the crisis of the metaphysical foundations of human existence is due to the fact that humanity is in a crisis of global development of the world associated with the ...Fourth Industrial Revolution 4.0, the technological development of the world, the demographic and environmental crisis, the epidemic of the coronavirus COVID-19. The purpose of the study is to conceptualize the socio-philosophical reflection of the crisis of the metaphysical foundations of human existence, which is a global problem of our time, which threatens our civilization, is associated with economic and social development, with many problems, including the problem of COVID-19. The objectives of the research are to identify the problems of the metaphysical dimensions of human existence and find ways that promise to lead to great achievements - to raise living standards, create new economic opportunities, solve anthropological, existential and ontological problems of human being associated with the real de-objectification of human existence, loss of the integrity of self-determination.The scientific novelty of the research is that it presents a solution to new problems of the crisis of the metaphysical foundations of human existence and ways to solve them.
Intraspecific genetic differentiation of the trematode
Skrjabinolecithum spasskii
and its phylogenetic relationships with other species of the family Haploporidae were studied by comparing the ...nucleotide sequences of a part of the 28S rRNA gene and the ITS1-5.8S-ITS2 rDNA region. Trematodes were isolated from so-iuy mullet
Liza haematocheila
fishes collected in rivers of Primorye and flathead grey mullet
Mugil cephalus
fishes collected in water bodies of Vietnam (27 fishes in total). A phylogenetic analysis showed that
S. spasskii
is close to species of the genus
Capitimitta
of the subfamily Waretrematinae. By intraspecific variation of rDNA sequences, trematodes were divided into three groups with tree different genotypes, which had fixed nucleotide substitutions. Genotype I was found in trematodes from fishes collected in Primorye. Genotype II was detected in trematodes from
M. cephalus
fishes collected in the Tonkin Bay, Cat Ba Island, Vietnam. Genotype III was found in five trematodes from
L. haematocheila
collected in the Kievka River, Primorye. The genetic distances between genotypes I and III from Primorye were 0.4 and 0.65% by 28S and ITS rDNA sequences, respectively. The lowest genetic distances were observed between genotypes II (Vietnam) and III (Primorye), 0.1 and 0.33% by 28S and ITS rDNA sequences, respectively. Possible causes of genetic differentiation of
S. spasskii
from different geographic locations and different definitive host species are discussed.
The search for MSSM Higgs bosons will be an important goal at the LHC. We analyze the search reach of the CMS experiment for the heavy neutral MSSM Higgs bosons with an integrated luminosity of 30 or ...60 fb-1. This is done by combining the latest results for the CMS experimental sensitivities based on full simulation studies with state-of-the-art theoretical predictions of the MSSM Higgs-boson properties. The results are interpreted in MSSM benchmark scenarios in terms of the parameters tan β and the Higgs-boson mass scale, MA. We study the dependence of the 5σ discovery contours in the MA–tan β plane on variations of the other supersymmetric parameters. The largest effects arise from a change in the higgsino mass parameter μ, which enters both via higher-order radiative corrections and via the kinematics of Higgs decays into supersymmetric particles. While the variation of μ can shift the prospective discovery reach (and correspondingly the ”LHC wedge” region) by about Δtan β=10, we find that the discovery reach is rather stable with respect to the impact of other supersymmetric parameters. Within the discovery region we analyze the accuracy with which the masses of the heavy neutral Higgs bosons can be determined. We find that an accuracy of 1–4% should be achievable, which could make it possible in favorable regions of the MSSM parameter space to experimentally resolve the signals of the two heavy MSSM Higgs bosons at the LHC.
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