Accretion spin-up of the massive component in the neutron star stripping model for short gamma-ray bursts

In this paper, we use analytical methods to study the last stages of the double neutron star (NS) system evolution. Depending on the initial masses of the components, this evolution can occur either in the framework of the merging scenario or in the NS stripping model. The main new ingredient of this work, compared with the previous calculations, is accounting for accretion spin-up of the massive component. This effect leads to a significant decrease in the duration of the stable mass transfer of matter in the stripping mechanism. Within the framework of the Newtonian approximation, we determine the mass boundary between the merging and stripping scenarios. It is shown that this boundary weakly depends on the total mass of the system and the specific form of the NS equation of state and is determined mainly by the initial mass ratio of the components. The stripping scenario is realized at M2/M1<0.8, so it should make a large contribution to the population of close to us gravitational wave events from NS-NS coalescing binaries and accompanying short gamma-ray bursts. Nevertheless, the value obtained requires further clarification, taking into account relativistic effects, possible non-conservative mass transfer, etc.Comment: 10 pages, 5 figure

Dynamics of direct impact accretion in degenerate binary systems

We consider the gas dynamics in an accreting binary system of degenerate stars within the framework of the Newtonian approximation. In such a system, the accretion stream can impact the surface of a white dwarf (WD) or neutron star (NS) as a result of the very compact orbit. This causes a loss of angular momentumfrom the orbit and spin-up of the accretor. We construct approximations for the specific angular momentum of the accreting matter which goes to spin up the accretor and some other parameters of the system. It is shown that the obtained approximation of the specific momentum is qualitatively different from the widely used Keplerian formula. It should affect the boundary between scenarios of immediate tidal disruption and slow mass loss of the donor in WD-WD and NS-NS binaries, as well as the time of stable mass transfer in the stripping scenario.Comment: 8 pages, 9 figs, 6 tables. Submitted to MNRA

Corporate education system as a factor of ensuring modern companies’ financial stability

Purpose: This article aims to identify the role of corporate universities opened by large holdings for their employees’ effective training as a part of the company’s mission implementation and ensuring business financial stability strategy. Design/Methodology/Approach: To implement flexible project management of the companies’ financial stability, a concept of corporate university development is presented on the grounds of a competency-based approach. Main emphasis of the competency-based approach is aimed at the labor functions performance and establishment of a correlation between competence and labor efficiency of employees. Findings: Methods and techniques of corporate education are aimed at creating human capital development optimal model, ensuring the company’s financial stability. Practical Implications: The study results were tested as part of a corporate retraining program for the specialists at the “Russian Railways” company in Rostov-on-Don. Participation in corporate university programs allows employees responding quickly to market changes. Originality/value: Main contribution of this study is to create an algorithm for transmitting the company's strategy to all management levels. The tools for key changes in the company’s organizational and financial management system are formed at a corporate university.peer-reviewe

The choice of a method for selecting and determining the quantitative and qualitative content of microplastics in wastewater

A general growth in the polymers production and consumption leads to an increase in the new types of wastes. In conjunction with the lack of secondary recycling power this fact is being a reason for appearance of a new processes that is potentially destructive for the environment. In particular, plastic wastes that is being stored in the wastewater of a large cities under a combination of aggressive factors action such as humidity, mechanical and UV-erosion degrades into a small-size particles, famously known as microplastics (MP). The study presented is devoted to the methodology development for acquisition, quantitative and qualitative analysis of wastewater derived microplastics. An experimental part deals with real wastewater samples collected at different infrastructurally-important objects of Rostov-on-Don and Aksai cities. For all the sampling locations the presence of urban-generated MP particles is approved. The results show that the research methods used are able to satisfy the output data quality conditions. However, the significant time and cost consumption of the research chain developed limits its wide practical application

Cement-free binders for radioactive waste produced from blast-furnace slag using vortex layer activation technology

The paper addresses the issue of recycling granulated blast-furnace slag (gBFS) as a source for production of cement-free binder materials for further usage in rare-earth metals production for radioactive waste disposal. The use of the vortex layer activator was provided as main technique allowing to produce high-dispersed chemically activated binders. The paper examines the effect of processing conditions on the physical-chemical and mechanical properties of the resulting BFS-based cement-free materials and gBFS-based concretes

New aspects of the QCD phase transition in proto-neutron stars and core-collapse supernovae

The QCD phase transition from hadronic to deconfined quark matter is found to be a so-called "entropic" phase transition, characterized, e.g., by a negative slope of the phase transition line in the pressure-temperature phase diagram. In a first part of the present proceedings it is discussed that entropic phase transitions lead to unusual thermal properties of the equation of state (EoS). For example one finds a loss of pressure (a "softening") of the proto-neutron star EoS with increasing entropy. This can lead to a novel, hot third family of compact stars, which exists only in the early proto-neutron star phase. Such a hot third family can trigger explosions of core-collapse supernovae. However, so far this special explosion mechanism was found to be working only for EoSs which are not compatible with the 2 M⊙ constraint for the neutron star maximum mass. In a second part of the proceeding it is discussed which quark matter parameters could be favorable for this explosion mechanism, and have sufficiently high maximum masses at the same time

Destruction mechanisms and methods of laboratory autoclave tests of internal coatings of oil pipes

The main mechanisms of destruction of internal anticorrosive polymer coatings (IACPC) of the inner surface of tubing and fielding pipes are review in the article. They are divide into decompression peeling, substrate destruction under the corrosion of and natural aging of the polymeric basis. A critical analysis of the existing standards for the testing of internal anticorrosive coatings was made. The carrying out test on these documents does not allow obtaining the destructions identical to those found during the exploitation of pipelines. Investigations on the selection of optimal regimes of autoclave tests and the methodology for conduct research are describe. A comparison for the results of laboratory and experimental field tests of the coatings presented. Document type: Articl

Genotyping and Whole-Genome Resequencing of Welsh Sheep Breeds Reveal Candidate Genes and Variants for Adaptation to Local Environment and Socioeconomic Traits

Background: Advances in genetic tools applied to livestock breeding has prompted research into the previously neglected breeds adapted to harsh local environments. One such group is the Welsh mountain sheep breeds, which can be farmed at altitudes of 300 m above sea level but are considered to have a low productive value because of their poor wool quality and small carcass size. This is contrary to the lowland breeds which are more suited to wool and meat production qualities, but do not fare well on upland pasture. Herein, medium-density genotyping data from 317 individuals representing 15 Welsh sheep breeds were used alongside the whole-genome resequencing data of 14 breeds from the same set to scan for the signatures of selection and candidate genetic variants using haplotype- and SNP-based approaches.Results: Haplotype-based selection scan performed on the genotyping data pointed to a strong selection in the regions of GBA3, PPARGC1A, APOB, and PPP1R16B genes in the upland breeds, and RNF24, PANK2, and MUC15 in the lowland breeds. SNP-based selection scan performed on the resequencing data pointed to the missense mutations under putative selection relating to a local adaptation in the upland breeds with functions such as angiogenesis (VASH1), anti-oxidation (RWDD1), cell stress (HSPA5), membrane transport (ABCA13 and SLC22A7), and insulin signaling (PTPN1 and GIGFY1). By contrast, genes containing candidate missense mutations in the lowland breeds are related to cell cycle (CDK5RAP2), cell adhesion (CDHR3), and coat color (MC1R).Conclusion: We found new variants in genes with potentially functional consequences to the adaptation of local sheep to their environments in Wales. Knowledge of these variations is important for improving the adaptative qualities of UK and world sheep breeds through a marker-assisted selection.</p