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Electrical and radiation characteristics of inductively-coupled ferrite-free low mercury pressure discharges exited at a frequency of 13.56 MHz and discharge plasma power, Ppl = (5 ? 300) W, in closed-loop quartz tubes of 815 mm in length and of 16.6 mm in diameter were experimentally stud-ied. Discharges were excited and maintained with the help of one-turn induction coil made from litz wire and disposed on the tube wall surface along tube perimeter. Tubes were filled with mercury vapour (~ 10Ц2 Torr) and argon (0.5, 0.7, 1.0, and 2.0) Torr. As discharge plasma power, Ppl, were increased from 130 W to 275 W, coil resonant frequency (RF) voltage grew from (560 ? 700) V up to (840 ? 860) V, RF coil current grew from (1.4 ? 1.8) A up to (2.4 ? 2.6) ј. Coil power losses was highest in the lamp with argon pressure of 0.5 Torr and grew from 30 W (Ppl = 150 W) to 70 W (Ppl = 230 W). UV resonant (254 nm) radiation flux grew with plasma power and was highest in the lamp (pAr = 0.5 Tоrr) while UV radiation generation ef-ficiency of this lamp had maximal value of 34 % at plasma power of 130 W.

Radiation and electrical characteristics of ferrite-free closed-loop inductively-coupled low mercury pressure UV lamps of 375 mm in length and 120 mm in width were experimentally studied. Discharges were excited at a frequency of 1.7 MHz and lamp RF power, Рlamp = (95–170) W. It was in quartz closed-loop tubes of 16.6 mm in inner diam. and of 815 mm in length, in the mixture of mercury vapour (7 х 10–3 mm Hg) with Ar (0.7 and 1.0 mm Hg) and with the mixture of 30 % Ne + 70 % Ar (0,7 and 1,0 mm Hg). The 3-turn induction coil made from litz wire with a low specific linear resistance (ρw = 1.4 x 10–4 Ohm/cm) was disposed on the lamp surface along the closed-loop tube perimeter. In lamps with buffer gas pressure of 1,0 mm Hg, the increase of lamp power from 95 to 150 W caused the decrease of induction coil power losses, Pcoil, from (6–7) W to (3–4) W. Also in these lamps increased induction coil power efficiency, ƞcoil = 1 – Pcoil/Plamp, from 92 % to 97 % and lamp UV radiation (λ = 254 nm) generation efficiency, ƞe, 254, from 57 % to 66 %. The decrease of buffer gas pressure from 1.0 to 0.7 mm Hg caused the decrease of ƞe, 254 by (10–20)%.

The electrical and radiation characteristics of innovative high-efficient 254-nm wavelength ultraviolet (UV) radiation sources employing ferrite-free inductively-coupled low-pressure discharges excited in closed-loop quartz tubes are experimentally studied. The discharge was excited using a 3-turn induction coil at a frequency of 1.7 MHz and lamp power equal to 90-160 W in a mixture of mercury vapor at a pressure of around 0.01 mmHg and buffer gas (Ar, a mixture of 30%Ne+70%Ar) at pressures of 0.7 and 1.0 mmHg in a closed tube 16.6 mm in diameter and 815 mm long. The coil turns made of multiconductor wire (Litz wire) with a low per unit length resistivity of 0.00014 Ωm/cm and 1.5 mm in diameter were arranged over the discharge tube perimeter. It was found that, as the lamp power was increased, the power loss in the induction coil wire decreased from 7-9 to 3-4 W, and the coil efficiency increased from 92 to 98%. In lamps filled with buffer gas at a pressure of 1.0 mmHg, the maximal plasma UV radiation generation efficiencies equal to 68% and 66%, respectively, were achieved at plasma power levels of 105-155 W. The decrease of buffer gas pressure to 0.7 mmHg entails a drop of lamp UV radiation generation efficiency by 10-20% and a shift of its maximum values to the zone of lower plasma power values.

Obtaining detailed information regarding the interfacial characteristics of metal/hexagonal-TMN composites is imperative for developing these materials with optimal mechanical properties. To this end, we systematically investigate the work of adhesion, fracture toughness, and interfacial stability of M/Cr2N and M/V2N interfaces using first-principles calculations. The orientation (0001) of hexagonal phases and (111) of fcc phases are selected as the interface orientations. Accordingly, we construct M/Cr2N interface models by considering 1N, 2N, and Cr terminations of Cr2N(0001), as well as two stacking sequences (top and hollow sites) for the 1N- and 2N-terminated interface models, respectively. The M/V2N interface models are constructed in the same way. The V-terminated Ni/V2N interface is demonstrated to provide a good combination of the work of adhesion, fracture toughness, and interfacial stability. Therefore, the Ni/V2N interface model can be regarded as the preferred configuration among the metal/hexagonal-TMN interface models considered. The present results offer a practical perspective for tailoring the interfaces in metal/hexagonal-TMN composite materials to obtain improved mechanical properties.

Experimental study of characteristics of a nonferrite electrode-less UV lamp with a length of 500 mm and width of 130 mm in the form of a closed quartz discharge tube with an inner diameter of 25 mm was conducted. The induction discharge was excited at a frequency of 1.7 MHz within the discharge lamp power Ppl ranging between 52 and 112 W in a mixture of mercury (~10-2 mm Hg) and argon (1.0 mm Hg) vapours by means of a 3-coil inductance located along the inner perimeter of the closed tube. With Ppl increasing: a) loss power in the inductance wire first decreased from 37 down to 22 W (Ppl = 84 W) and then increased up to 44 W; 2) the UV radiant flux of the lamp in a mercury light-band of 54 nm increased from 28 to 72 W; 3) radiant efficiency of the lamp at the light-band of 254 nm first increased from 31 to 48.5 % (Ppl = 84 W) and then slightly decreased down to 46 %; 4) radiant efficiency of the discharge plasma at the wavelength of 254 nm increased from 53 % to 65 %.

Naturalistic depictions of animals are a common subject for the world's oldest dated rock art, including wild bovids in Indonesia and lions in France's Chauvet Cave. The oldest known Australian Aboriginal figurative rock paintings also commonly depict naturalistic animals but, until now, quantitative dating was lacking. Here, we present 27 radiocarbon dates on mud wasp nests that constrain the ages of 16 motifs from this earliest known phase of rock painting in the Australian Kimberley region. These initial results suggest that paintings in this style proliferated between 17,000 and 13,000 years ago. Notably, one painting of a kangaroo is securely dated to between 17,500 and 17,100 years on the basis of the ages of three overlying and three underlying wasp nests. This is the oldest radiometrically dated in situ rock painting so far reported in Australia.

The brittleness and relatively poor adhesion properties of CrN materials have been extensively addressed by developing Ni/CrN composites with a separate Ni phase. However, conditions at the Ni/CrN interfaces, which are the key features leading to the enhanced toughness, remain poorly understood. The present work addresses this issue by investigating the effect of interface orientation on adhesion strength and fracture toughness of Ni/CrN interfaces using first-principles calculations. To this end, we build seven Ni/CrN interface models, including Ni(100)/CrN(100), Ni(110)/CrN(110), Ni(110)/CrN(111), and Ni(111)/CrN(111), with different interface orientation and stacking orders. The results demonstrate that the interface orientation plays a predominant role in determining the mechanical properties of the Ni/CrN interfaces, while the effect of stacking order can be neglected. The Ni(111)/CrN(111) interface is demonstrated to provide the greatest adhesion strength, interfacial stability, and fracture toughness among the Ni/CrN interfaces considered, and is therefore the preferred orientation for Ni/CrN composite applications.

Biological transposons serve as an inspiring model for evolutionary computations.We add new objects to the standard toolkit of GA - artificial transposons.The artificial transposons are codes served by their own operators.Our enhancement of GA by the transposons increases the efficiency of searching.Co-evolution of the transposons and host chromosomes is related to the efficacy. Modern evolutionary computation utilizes heuristic optimizations based upon concepts borrowed from the Darwinian theory of natural selection. Their demonstrated efficacy has reawakened an interest in other aspects of contemporary biology as an inspiration for new algorithms. However, among the many excellent candidates for study, contemporary models of biological macroevolution attract special attention. We believe that a vital direction in this field must be algorithms that model the activity of "genomic parasites", such as transposons, in biological evolution. Many evolutionary biologists posit that it is the co-evolution of populations with their genomic parasites that permits the high efficiency of evolutionary searches found in the living world. This publication is our first step in the direction of developing a minimal assortment of algorithms that simulate the role of genomic parasites. Specifically, we started in the domain of genetic algorithms (GA) and selected the artificial ant problem as a test case. This navigation problem is widely known as a classical benchmark test and possesses a large body of literature. We add new objects to the standard toolkit of GA - artificial transposons and a collection of operators that operate on them. We define these artificial transposons as a fragment of an ant's code with properties that cause it to stand apart from the rest. The minimal set of operators for transposons is a transposon mutation operator, and a transposon reproduction operator that causes a transposon to multiply within the population of hosts. An analysis of the population dynamics of transposons within the course of ant evolution showed that transposons are involved in the processes of propagation and selection of blocks of ant navigation programs. During this time, the speed of evolutionary search increases significantly. We concluded that artificial transposons, analogous to real transposons, are truly capable of acting as intelligent mutators that adapt in response to an evolutionary problem in the course of co-evolution with their hosts.

Surface magnetoelastic Love waves in a regularly stratified medium with ferrite and dielectric layers are studied based on the Hamilton formalism and numerical procedures. The dispersion relations are analyzed for particular structures

We argue that the process of the origin and evolution of living organisms is indivisible from the process of the origin and evolution of biosphere, the global planetary system. The most general features of biosphere evolution as a directed process are formulated in the principle of “bio-actualism”. It is demonstrated, that this principle, stated for Phanerozoic eon, hold for early biosphere up to the period of biosphere coming into being. To support this thesis we considered an episode of pre-Cambrian history – Vendian phytoplanktonic crisis.

In this article the new epoch of modern biosphere evolution is discussed. This epoch can be characterized as a period of strong increasing of non‐genetic informational exchange between individuals of new Homo species. The peculiarities of this informational epoch are connected with the following: ecological features of any human ethno‐population depend on not only “genetic luggage” but mental outfit, in other words human culture. The ethno‐population culture is conditioned on the total of collective experiences and, hence, the informational exchange between the population members. The accumulation of the experiences along evolution needs specific mechanisms of memory. The knowledge libraries which are outside of man organisms are one of such ways. To understand main traits of the modern biosphere evolution we can try to translate some known regularities for biodiversity and ecosystem evolution to the ethno‐populations.