Pulsed Laser Deposition of Large‐Area Thin Films and Coatings

Simple and inexpensive methods of obtaining large‐area uniform in thickness and composition thin films on rotating substrates and moving ribbons through pulsed laser deposition have been proposed. Thin films of different compositions were prepared using these methods. The thickness uniformity of obtained films was preserved within the limits of ±3% on up to 300 mm diameter substrates. Also, a method of creating a laser spot with a certain configuration on the target is proposed allowing almost full utilization of the target material

Large Scale Properties of Tilt of Sunspot Groups and Joy's Law Near The Solar Equator

We present a physical mechanism of formation of tilt angles of sunspots due to the process of formation of active regions below the solar photosphere. The contribution of Coriolis force factors on large-scale flows of super-granular convection in turbulent media has been investigated in details. On the basis of earlier works by Kleeorin et al. (2016) and Safiullin et al. (2018) we give physical estimates of orders of magnitude of the effect and estimate the tilt angles near the solar equator, in the "Royal" zone of solar activity. The above model is based on the balance of the small-scale and large scale magnetic helicities and describes in details the sunspot formation process over the last five solar cycles (since 1964). We adopt this model for a wider class of manifestations of solar activity. We present latitudinal dependence of the mean tilt on these five solar cycles and time-latitudinal diagrams over a limited range of latitudes and phases of the solar cycle.Comment: manuscript in Russian, total 17 pages, 4 figures (with Abstract and Figures, Astrophysics[Armenia], accepted for publication in 2019

Environmental aspects of post-operational bioremediation of the typical municipal solid waste landfill of the administrative district

The article deals with the environmental consequences o f testing the method o f biological remediation o f the closed typical municipal solid waste landfill of the administrative district. The essence o f the method consists in the introduction of adapted composites from aboriginal, adapted or modified biological systems, primarily microorganisms for catalysis o f the decomposition process o f the organic component of waste landfills and subsequent separation o f valuable recyclable materials. The article presents the results o f the impact assessment o f a typical solid municipal waste landfil

Thermoelectric Cooling at Cryogenic Temperatures

Experimental results demonstrating Peltier cooling below 10 K are reported, using crystals of the thermoelectric cerium hexaboride (CeB6). Direct measurements of the Peltier cooling showed δT up to ∼0.2 K in magnitude at T∼4–5 K. All three kinetic parameters: resistivity (ρ), heat conductivity (k), and Seebeck coefficient (S), characterizing the thermoelectric figure of merit ZT=S2T/ρk, were measured, giving high-confidence results

Laser-Powered Thermoelectric Generators Operating at Cryogenic Temperatures

A thermoelectric generator, operating in a cryostat at liquid helium temperatures, is described. Energy to the generator is supplied via an external laser beam. For this prototype device the associated heat load at permanent operation is comparable with the heat load associated with power delivery via metallic wires. Estimates indicate that still better performance can be enabled with existing thermoelectric materials, thereby far exceeding efficiency of traditional cryostat wiring. We used a prototype generator to produce electric power for measuring critical currents in Nb3Sn-films at 4K

Sensor Development for Single-Photon Thermoelectric Detectors

As we reported earlier [1], thermoelectric detectors can be competitive as nondispersive energy resolving focal-plane instruments in X-ray/UV spectrum. The first generations of prototype devices demonstrated the viability of detector design and provided good agreement between theoretical expectations and experimental data. These devices exploited sensors made of gold with a small fraction of iron impurity. To get the projected high resolution one needs another type of material, namely, lanthanum-cerium hexaborides. We report on the first experimental tests of the feasibility of lanthanum-cerium films as sensor materials. Progress with thin films of these materials argues for the success of these thermoelectric detectors