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Ultra-low-radioactivity titanium alloys are promising materials for the manufacture of low-background detectors which are being developed for experiments in astroparticle physics and neutrino astrophysics. Structural titanium is manufactured on an industrial scale from titanium sponge. The ultra-low-background titanium sponge can be produced on an industrial scale with a contamination level of less than 1 mBq/kg of uranium and thorium isotopes. The pathways of contaminants during the industrial production of structural titanium were analyzed. The measurements were carried out using two methods: inductively coupled plasma mass spectroscopy (ICP-MS) and gamma spectroscopy using high-purity germanium detectors (HPGes). It was shown that the level of contamination with radioactive impurities does not increase during the remelting of titanium sponge and mechanical processing. We examined titanium alloy samples obtained at different stages of titanium production, namely an electrode compaction, a vacuum arc remelting with a consumable electrode, and a cold rolling of titanium sheets. We found out that all doped samples that were studied would be a source of uranium and thorium contamination in the final titanium alloys. It has been established that the only product allowed obtaining ultra-low-background titanium was the commercial VT1-00 alloy, which is manufactured without master alloys addition. The master alloys in the titanium production process were found cause U/Th contamination. [ABSTRACT FROM AUTHOR]

In this paper the robust output control with anti-windup compensation and its implementation to the robotic boat are addressed. The detailed control design and stability analysis of the closed-loop systems are provided in the work. Extensive experimental verification of the dynamic positioning system based on various modifications of the basic controller is carried out by means of robotic boat. The corresponding experimental results are presented and analysed.

Ultra-low-radioactive titanium is the main perspective material for cryostat fabrication in dark matter search experiments. The pathways of the uranium and thorium contamination of Ti sponges produced by the Kroll process were analyzed. The general role of Mg in Ti sponge contamination by U and Th was established. It was found that when transformed to MgCl2 in the Kroll process, Mg was purified from U and Th, and further MgCl2 reduction and sublimation makes it possible to produce low-radioactive Ti sponges. [ABSTRACT FROM AUTHOR]

Based on both theoretical and practical experiences, the measures aimed at controlling emergency shutdowns of stopes have been highlighted. These stopes are connected with the emergency rigid settlements of powered complexes. In terms of the Western Donbas mines, there are certain risks of a shutdown of stopping operations within the zone of primary roof caving. Thus, the causes of emergency rigid settlements of the support may include the following: layers of the main roof rocks are hanging and not timely delaminated; sudden changes in lithology; hydraulic overloading of the main roof; structural flaws of support under certain conditions of its use, etc. In this paper, the theoretical method of scientific cognition was applied, which, with its help, makes it possible to switch from single low-efficiency measures to a set of actions aimed at preventing any uncontrolled situation. Obtaining certain generalized knowledge means obtaining a much deeper representation of reality, penetrating into its essence. The study also involves statistical analysis, being the basis for outlining a zone of primary caving where a high degree of risk is observed. Certainly, the generalization of these measures does not solve the problem completely. Consequently, there will be further attempts to search for and achieve principal new solutions in the future. [ABSTRACT FROM AUTHOR]

To determine the effect of exposure of film composite electrodes based on Ni(OH)2-polyvinyl alcohol to an alkaline solution at high temperatures on the electrochromic and electrochemical characteristics, a series of films was obtained. The films were obtained on a glass substrate coated with fluorine-doped tin oxide. The coating of the substrates was carried out by the cathodic template method under the same conditions. The resulting precipitates were treated by keeping them in an alkali solution at different temperatures: 30, 40, 50, 60, and 70 °C for 8 hours, thereby simulating the operating conditions of an electrochromic device in a hot climate. It was found that the exposure temperature directly affected the electrochemical and electrochromic properties of the treated films. In this case, the cyclic volt-ampere curves showed a decrease in the peak values of the current densities and a lower rate of establishment of characteristics with an increase in the treatment temperature. At a maximum treatment temperature of 70 °C, the properties of the film significantly changed towards deterioration. According to the results of the experiments, three temperature ranges of treatment were identified. The first one was in the range up to 40 °C, in which the films showed significant electrochromic and electrochemical activity after treatment. The second interval was between 40 and 60 °C, in which the coatings showed a reversible deterioration in electrochromic and electrochemical activity. After treatment in the second interval, the films gradually restored their performance during electrochemical cycling. The third interval was from 70 °C and above. The films treated in this temperature range irreversibly lost their electrochemical and electrochromic activity. The study also proposed mechanisms to explain changes in the characteristics of electrodes during treatment, as well as possible ways to combat temperature degradation. [ABSTRACT FROM AUTHOR]

Peroxidase mimics of nanoscale materials as alternatives to natural peroxidases have found widespread uses in biomedicine. Among various types of peroxidase mimics, platinum-group metal (PGM) nanocrystals have drawn considerable attention in recent years due to their superior properties. Particularly, PGM nanocrystals display high catalytic efficiencies, allow for facile surface modifications, and possess excellent stabilities. This feature article summarizes our recent work on development of PGM nanocrystals as peroxidase mimics and exploration of their applications in in vitro diagnostics. We begin with a brief introduction to controlled synthesis of PGM nanocrystals in solution phase. We then elaborate on a variety of physicochemical parameters that can be carefully tuned to optimize the peroxidase-like properties of PGM nanocrystals. Then, we highlight the applications of PGM nanocrystals in different in vitro diagnostic platforms. We conclude this article with personal perspectives on future research directions in this emerging field, where challenges and opportunities are remarked. [ABSTRACT FROM AUTHOR]

Russia's level of pension provision lags most OECD countries, as well as faces challenges from rising pension fund deficits and an aging population. On the current course, in the long run Russia can expect decreased budget revenues that would require to adjust government spending. While many countries moved after the 2008 global financial crisis to overhaul their pension systems, Russia postponed action until recently. This paper presents estimates of retirement pension expenditures through 2035 under various assumptions about economic growth, demographic composition, and possible reforms to the pension system. Two recent measures by the government (abolition of indexing adjustments for working retirees and an increase in the retirement age for public servants) will slightly mitigate the long-term negative trends. For any of our assumptions, Russia's decision to begin raising the retirement age by six months a year starting in 2019 will put the retirement pension expenditures relative to GDP on the downward trajectory. This reform allows an accelerating increase in pensions to improve retiree welfare and makes up for some of expected decline in overall budget revenues, making it easier to stabilize the level of public spending relative to GDP. Acceleration of economic growth backed by structural reforms limits further the growth in pension expenditures. [ABSTRACT FROM AUTHOR]

The karyotype of Armenian populations of the black fly Prosimulium petrosum Rubtsov, 1955 was characterized and compared with that of all other chromosomally known Palearctic members of the Prosimulium hirtipes group. Analysis of the polytene chromosomes established that Prosimulium petrosum is most closely related to European populations of Prosimulium latimucro (Enderlein, 1925) with which it shares an identical fixed chromosomal banding sequence. Its validity as a species, separate from Prosimulium latimucro, is based on its unique sex-differential sections in the expanded centromere region of chromosome I, in agreement with the unique structural configuration of the hypostomal teeth of its larvae. Prosimulium petrosum and Prosimulium latimucro, therefore, are homosequential species, demonstrating the value of a combined chromosomal and morphological approach in determining species status. [ABSTRACT FROM AUTHOR]

This study examines Russia's short- and long run fiscal sustainability. The study reveals the possible risks, if fiscal sustainability deteriorates on the general government budget level. By employing a special fiscal stress index, Russia's public finances are evaluated as sustainable in the short run. In the long run, the study analyzes advantages and limitations of the new fiscal rules, compares the new rules with the previous fiscal rules suspended during the financial crisis and discusses the possibilities for further development of the fiscal rules in Russia. The official long run socio-economic development forecast is employed for the estimates. The analysis suggests that comparing to 2012 government revenue will decrease by 7.5 p.p. of GDP by 2050, explained by the drop in oil-and-gas revenue by 8.7 p.p. of GDP. Government expenditure will decrease by 6.0 p.p. of GDP. The value of government net worth will become negative by 2050 but on the infinite projection horizon should stabilize on the safe level close to -15% of GDP. [ABSTRACT FROM AUTHOR]

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