Istraživanje reaktivno nanešenih NbN slojeva

We have investigated the structural properties of thin films of reactively magnetron sputtered niobium nitride (NbN) under high-temperature annealing (with annealing temperatures ranging 850 to 950 ° C) and with different nitrogen contents in the working gas mixture. Prepared NbN films were characterized by Auger electron spectroscopy (AES) and X-ray diffraction (XRD). The influence of rapid thermal annealing (RTA) on a change of the structure properties and surface morphology was investigated. The correlation between technological parameters and film properties, structure and composition were established.Istraživana su strukturna svojstva tankih slojeva niobium nitrida (NbN) reaktivnorasprašenih magnetronom, uz visoko-temperaturno otpuštanje (na 850 do 950 ◦C), s različitim sadržajima dušika u radnom plinu. Dobiveni NbN tanki slojevi istraženi su Augerovom elektronskom spektroskopijom (AES) i rendgenskom difrakcijom (XRD). Proučavan je utjecaj brzog toplinskog otpuštanja na strukturna svojstva i površinu slojeva

Hydraulic motor with swinging planetary drive of bevel gears and its force & efficiency calculation

A new kind of hydraulic motor with offset swining planetary drive of bevel gears and the application in Capstan is presented; the researched of the calculation of the efficiency of the mechanism is made. Compared to the former structure, new kind of structure has many advantages over that of the old structure. The hydraulic driving system in the traditional derrick car is: hydraulic motor drives a reducer, and then the reducer in turn drives a capstan. Another hydraulic driving system is: an axial piston motor and an internal cycloid pinwheel drive are applied, so that the reducer and the capstan are combined into one so that simplified the transmission system. In the third version, a hydraulic motor is applied, which can be considered as the combination of hydraulic motor with axial piston and the planetary reducer and then drives the capstan, so that simplified the transmission system as well. The new kind of hydraulic motor with offset swing planetary drive of bevel gears, which combined the hydraulic motor, the internal planetary reducer with bevel gears, and the capstan together, is the most compact structure. It is of more advantage in the occasion when space is extremely limited. In the paper, two kind of construction of this mechanism is presented, and the analysis of the efficiency of this kind of transmission is made as well

Highly effective way in five-axis sculptured surfaces machining using flat-end cutter

This paper applied the concept of “contact” in Differential Geometry into the machining of the sculptured surface. I presented the contact principle of the machining of complicated surfaces, using the circumference circle of the cylindrical cutter to sweep the curved surface instead of ball-end mill. This is highly effective method. In this paper an theory for machining complicated surface is presented. By using a flat-end mill instead of ball-end mill, and adjusting the axis relate to the surface, the two surfaces, The swept surface and the required surface, has the same curvature, up to as high as 3th order

The second fundamental law of gearing and contact stress calculation of high order contact gearing

After an extensive research on the fundamental theory, the theoretical basis for the Logix gearing will be presented in this paper. This includes the theory for gear meshing with high degree of contact. In comparison to previous studies, the theory of this paper is more restricted going beyond third order parameters into the fourth order, the teeth profile had one order of contact higher than that of the Logix gearing. So that further improved the contact strength of tooth profile. A large category of gearings with high order of contact was presented, while the Logix gear is only one of them, or the special example in realization of my theory. In the Logix gearing, the zigzag curvature center curve of media rack does not always lay about the pitch line and does not extend along the pitch line continuously and steadily. It goes forward and returns. So that, in terms of properties of the transverse engagement, the Logix gearing has not much improvement over the traditional Novikov gearing (in which the transverse engagement is temporally). In my gearing the curvature center of basic rack extend along the pitch line continuously and steadily. The transverse engagement factor is larger than that of Logix gearing

ASSESMENT OF DAMAGE OF SOLAR HETEROJUNCTION a-SiC/c-Si INDUCED BY NEUTRON RADIATION

Amorphous silicon carbide is known as a material resistant except others influences also against radiation. This study investigates the effects of neutron radiation on electric characteristics (I-V characteristic, impedance spectra and obtained dynamic parameters of AC equivalent circuit) of solar cell a-SiC/c-Si heterojunction structure. The heterojunction structure was irradiated using neutrons with neutron fluence 1013 cm-2. Existence of neutron induced structural defects, which could be introduced within semiconductor structure of heterojunction, has been illustrated using DC and AC analysis. The structural defects induced by neutron particles radiation affect mainly trapping mechanism. The process results in the changes of electronic elements included into proposed equivalent circuit

Nanogranular MgB2 thin films on SiC buffered Si substrates prepared by in-situ method

MgB2 thin films were deposited on SiC buffered Si substrates by sequential electron beam evaporation of B-Mg bilayer followed by in-situ annealing. The application of a SiC buffer layer enables the maximum annealing temperature of 830 C. The Transmission Electron Microscopy analysis confirms the growth of a nanogranular MgB2 film and the presence of a Mg2Si compound at the surface of the film. The 150-200 nm thick films show a maximum zero resistance critical temperature TC0 above 37 K and a critical current density JC ~ 106 A/cm2 at 11K.Comment: 7 pages, 6 figures, submitted to Applied Physics Letter

A synthesis of women's participation in small-scale fisheries management : why women's voices matter

Unidad de excelencia María de Maeztu CEX2019-000940-MAltres ajuts: acords transformatius de la UABWhile women globally make up nearly half of the fisheries workforce, their contribution to the sector has long been overlooked with implications for fisheries management. To assess women's participation in small-scale fisheries (SSF) management and related socio-cultural, environmental, and economic impacts, we conducted a systematic review of peer-reviewed literature (n = 124 case studies). Women had no or limited participation in more than 80% of the examined case studies reporting their participation level in SSF management. Women's exclusion from SSF management resulted in negative outcomes, whereas their active participation was associated with various positive impacts at multiple scales. Most of the documented impacts were socio-cultural, suggesting a gap in documenting environmental impacts stemmed from women's participation in SSF management. Importantly, most impacts reported affected the social-ecological system scale, suggesting that gender inclusion may contribute to improving the management of SSF social-ecological systems. We conclude by highlighting the need to foster gender perspectives in data collection methods used in fisheries research, in SSF management, and in ecological research on SSF social-ecological systems

Two-Dimensional Noble Metal Chalcogenides in the Frustrated Snub-Square Lattice

We study two-dimensional noble metal chalcogenides, with composition {Cu, Ag, Au}2{S, Se, Te}, crystallizing in a snub-square lattice. This is a semi-regular two-dimensional tesselation formed by triangles and squares that exhibits geometrical frustration. We use for comparison a square lattice, from which the snub-square tiling can be derived by a simple rotation of the squares. The mono-layer snub-square chalcogenides are very close to thermodynamic stability, with the most stable system (Ag2Se) a mere 7 meV/atom above the convex hull of stability. All compounds studied in the square and snub-square lattice are semiconductors, with band gaps ranging from 0.1 to more than 2.5 eV. Excitonic effects are strong, with an exciton binding energy of around 0.3 eV. We propose the Cu (001) surface as a possible substrate to synthesize Cu2Se, although many other metal and semiconducting surfaces can be found with very good lattice matching