The paper suggests a method for protection of galvanized steel from atmospheric corrosion, which involves the laser treatment of its surface followed by exposure to an ethanolicsolution of octadecylphosphonic acid (& Scy;(18)& Rcy;). The advantages of the proposed method include its environmental safety and high anticorrosion efficiency, along with a small thickness of films formed (up to 10nm) and the use of low concentrations of the non-toxic organic corrosion inhibitor. The surface morphology, composition, hydrophobic and anticorrosion properties of thin films formed with & Scy;(18)& Rcy; on laser-nanostructured surface of galvanized steel were studied by SEM, EDX, XPS, water contact angle measurement and corrosion tests. It is shown that laser treatment of the surface of galvanized steel gives it a polymodalmorphology and enriches the surface layer of metal with zinc oxides, including non-stoichiometric zinc oxide (Zn0.44O0.56).Such preparation of the metal surface makes it possible to obtain stable superhydrophobic protective films (the water contact anglereaches 163 +/- 2 degrees) in a solution of C18P. chemisorbs on a zinc coating, forming an ultrathin protective film consisting of zinc octadecylphosphonate, ZnO and Zn(OH)(2), as well as physically adsorbed C18P molecules. The combination of the superhydrophobicproperties of the alkylphosphonate film with its structure and strong adsorption causes its high anticorrosion efficiency in acorrosive atmosphere of 100% relative humidity with condensation of moisture on the surface and in a neutral salt spray atmosphere.

Optical and photoemission measurements were performed on alkali antimonide Na2KSb and Na2KSb/CsxSb photocathodes in order to determine their energy-band diagrams, elucidate the photoemission pathways, and explore the options for interface engineering in order to reach high quantum efficiencies of the photocathodes. This study is motivated by the recent discovery of optical orientation in Na2KSb and emission of spin-polarized electrons from Na2KSb/C(x)sSb photocathodes [V.S. Rusetsky et al., Phys. Rev. Lett. 129, 166802 (2022)]. We have shown that the band gap E-g of Na2KSb at =295 K lies within the range of 1.40-1.44 eV. The Na2KSb surface activation by the deposition of Cs and Sb results in effective electron affinity decrease by approximately 0.37 eV, and in an increase of the quantum efficiency up to 0.2 electrons per incident photon. The analysis of longitudinal energy distribution curves (EDCs) proves that the surface of activated Na2KSb/CsxSb photocathodes have negative effective electron affinity of approximately -0.1 and -0.25 eV at =295 and 80 K, respectively. EDC measurements under increasing photon energy demonstrate the transition of photoemission pathway from the surface states' photoionization at (h) over barw < E-g to the emission from the conduction-band bottom at approximate to and from the states with high kinetic energy in the conduction band at <(h)over bar>w > E-g. EDCs measured at 80 K reveal a highly directional photoelectron emission from the Na2KSb/CsSb photocathode, as compared to the p-GaAs(Cs,O) photocathode. This fact, along with the observed significant, by an order of magnitude, increase in the photoluminescence intensity under the Na2KSb surface activation by Cs and Sb, indicates relatively weak diffuse scattering in the "quasiepitaxial" CsxSb activation layer of a Na2KSb/CsSb photocathode, compared to strong scattering in the amorphous (Cs,O) activation layer of a p-GaAs(Cs,O) photocathode.

An analog of the optical polarizer/analyzer for electrons, a spin filter based on freestanding ferromagnetic (FM) nanomembrane covering the entrance of the microchannel plate (MCP) was applied for efficient spin filtering and electron amplification in the 2D field of view. To study the spin dependent transmission, we constructed a spin-triode device (spintron), which consists of a compact proximity focused vacuum tube with the Na2KSb spin-polarized electron source, the FM-MCP and phosphor screen placed to run parallel to each other. Here, we demonstrate the fabrication of FM nanomembranes consisting of a Co/Pt superlattice deposited on a freestanding 3 nm SiO2 layer with a total thickness of 10 nm. The FM-MCP has 10e6 channels with a single-channel Sherman function S=0.6 and a transmission of 1.5x10e-3 in the low electron energy range. The FM-MCP-based device provides a compact optical method for measuring the spin polarization of free electron beams in the imaging mode and is well suited for photoemission spectroscopy and microscopy methods.

The work suggests an environmentally friendly and efficient method of galvanized steel passivation for protection from atmospheric corrosion, which can serve as an excellent alternative to toxic chromate treatment.In particular, an important advantage of such passivation is the use of aqueous solutions of corrosion inhibitors (or those containing no more than 10% ethanol) to obtain superhydrophobic nanoscale anticorrosion films, which makes it a fire safe method.The method is based on laser and heat treatment of galvanized steel surface followed by layer-by-layer chemisorption of sodium dodecylphosphonate (SDDP) and vinyltrimethoxysilane (VTMS) or n-octyltriethoxysilane (OTES).A comparative assessment of the thickness, protective, hydrophobic properties and stability of thin coatings formed by layer-by-layer adsorption of the alkylphosphonate and trialkoxysilanes on the surface of galvanized steel with different morphology was carried out.It was shown that preliminary modification of the galvanized steel surface using laser exposure and heating enhances the protective and hydrophobic properties of the nanoscale phosphonate-siloxane films formed and increases its corrosion resistance in corrosive atmospheres.The polymodal morphology of the galvanized steel surface obtained using a laser promotes strong adsorption of the lower phosphonate layer, which in combination with the barrier properties of the siloxane network in the top layer, provides high protective and hydrophobic properties of phosphonate-siloxane films and their stability in corrosive atmospheres.The most effective method involves the layer-by-layer passivation of laser textured surfaces of galvanized steel with SDDP and OTES, which allows one to obtain stable superhydrophobic coatings with high anticorrosive properties in corrosive atmospheres of high humidity and salt spray.

При нанесении на поверхность полупроводников атомов цезия и кислорода можно добиться состояния эффективного отрицательного электронного сродства (ОЭС) поверхности. Фотокатоды на основе GaAs с ОЭС широко применяются в научных и технических приложениях, таких как генерация пучков спин-поляризованных и моноэнергетических электронов, детектирование света с однофотонной чувствительностью и высоким пространственным и временным разрешением. Одним из важных параметров фотокатода является его время жизни.

The paper considers the features of constructing an information model of the human peripheral auditory system in the LabVIEW software environment. A brief description of the adopted information model proposed for implementation in the software environment is given. Detailed explanations are described for each element of the model made in the LabVIEW environment. The main functionality of the user part of the program is presented. The work is, in fact, staged in nature and offers a sequence of further necessary studies of the developed model.

Полупрозрачные p-GaAs(Cs,O)-фотокатоды с эффективным отрицательным электронным сродством (ОЭС) применяются в настоящее время в электронно-оптических преобразователях, координатно-чувствительных детекторах, в источниках спин-поляризованных и монохроматических электронов. Каждая из областей практического применения требует оптимизации параметров pGaAs(Cs,O)-фотокатода. Научно-обоснованный подход к такой оптимизации предполагает, что хорошо известны: атомная структура ОЭС-интерфейса, его энергетическая диаграмма и процессы рассеяния, сопровождающие выход фотоэлектронов в вакуум. Наиболее информативный метод изучения энергетической диаграммы и процессов рассеяния основан на анализе энергетических и угловых распределений эмитированных в вакуум фотоэлектронов. С помощью данного метода, ранее, были проанализированы энергетические [1] и угловые [2] распределения термализованных фотоэлектронов. В результате, была предложена модель, в которой предполагалось, что выход в вакуум представляет собой “двухступенчатый процесс” и сопровождается “промежуточным захватом” фотоэлектронов в приповерхностные зоны размерного квантования.

Abstract The photoelectron processes in a p-GaN(Cs) photocathode with the effective negative electron affinity were studied experimentally within the 90–295 K temperature range. It was found that the photocathode illumination at the photon energies, which are below the energy gap of the p-GaN layer, increases the band bending at a semiconductor surface due to the photoemission from surface states.

Temperature and optical power density dependences of the photovoltage at a p-GaN(Cs) photocathode surface were measured in the temperature range 90–295 K. The study demonstrated that band bending at the p-GaN(Cs) photocathode surface can be reduced by ∼ 0.5 eV without modifying the surface atomic structure. The surface photovoltage impact on the p-GaN(Cs) photocathode quantum efficiency and photoelectron energy distributions was analyzed.

Spontaneous changes in photoemission properties of a р -GaN(Cs)–vacuum interface with effective negative electronic affinity induced by rearrangements of its atomic structure have been studied for the first time. The optimum Сs coating that ensures both the maximum photoelectron escape probability and its stability has been found. A thermodynamic model has been proposed to escape the relation of the photoemission properties of the р -GaN(Cs)–vacuum interface to its free energy and entropy.

Photoelectron scattering in a p-GaN(Cs,O) photocathode was studied by photoelectron emission spectroscopy at low temperatures. It has been experimentally established that the transfer of photoelectrons from the bulk of a p-GaN(Cs,O) photocathode to vacuum is accompanied by the emission of a cascade of optical phonons in the bulk and at the GaN-vacuum interface. Based on how the high-energy features of the photoelectron energy distribution shift with the photon energy, we find m(hh)/m(0) = 2.3 +/- 0.3.

It has been experimentally established that the transfer of photoelectrons from the bulk of a p-GaN (Cs,O) photocathode to vacuum is accompanied by the emission of a cascade of optical phonons. In the quantum efficiency spectrum of the p-GaN (Cs,O) photocathode, an exciton peak has been identified, indicating a significant contribution of the electron–hole interaction to the generation of free electrons in heavily doped p-GaN.

The problem of learning of complex visual stimuli in cognitive robotics is considered. These stimuli should be selected on the base of rules supporting arbitrary comparisons of stimulus features with features of other salient objects ( context). New perceptual knowledge representation based on the predicate logic is implemented to express such rules. Computable predicates are provided by low-level vision system. The rules are constructed using genetic algorithms on the base of a set of examples obtained by a robot during consequent trials. Dependence between the number of necessary trials and rule complexity is studied.

A Free-Electron Laser (FEL) places many exacting demands on a Negative Electron Affinity (NEA) photocathode, such as the need for an ultra-fast response time, low energy spread for emitted electrons, high quantum efficiency (Q.E.) and a high average photocurrent. However, these key requirements are conflicting, and cannot be fulfilled by conventional photocathode design. For example, to achieve similar to 10 ps response time, the photocathode active layer should be thinned to similar to 100 - 150 nm, but this thickness is insufficient to provide near-complete absorption of light with hv approximate to epsilon(g) so high Q.E. cannot be achieved. Complete optical absorption and high Q.E. can be obtained using a thin active layer at higher photon energies, but this generates photoelectrons with excess kinetic energy within the semiconductor. These photoelectrons do not thermalise in a thin active layer, so yield a broad energy distribution in the emitted electrons. Moreover, cooling of the conventional semiconductor photocathode structure is ineffective due to its fragility, so it cannot be pressed firmly to a heat sink to attain good thermal contact. Consequently, the maximum CW photocurrent is limited to a few milliamps. The goal of our work is to develop a new design of NEA-photocathode which is optimised for FEL applications.

4 V/cm. It is known from the literature (1) that this electric field accelerates thermalized photoelectrons to the saturation velocity, which is around 10 7 cm/sec. Thus photoelectrons are 'ejected' from the BG layer into the GaAs 'emitting' layer over an estimated time of approximately 3 ps. It then takes ~ 5 ps for photoelectrons to diffuse across the GaAs layer whose thickness is ~ 100 nm, then escape into the vacuum (2). Therefore, the estimated time response of a BG - photocathode does not exceed ~ 10 ps. To permit a comparative study of photoemission characteristics, a batch of test photocathodes with both BG and homogenous (HM) active layers were manufactured, with fig. 2 showing the BG-photocathodes. The thickness of HM active layer was equal to 130 nm, so slightly exceeds the 100 nm GaAs layer in the BG-photocathode. Both photocathodes were hermetically sealed within test parallel plate photodiodes. The anodes of these photodiodes were made of glass, covered with transparent and conductive In2 O3 layers. This permitted photoemission to be studied in both transmission- and reflection-mode illumination geometries. Figure 3 shows the test photodiodes. Longitudinal energy distributions for the emitted photoelectrons were measured by applying a retarding potential between photocathode and anode (3). Q.E.s were measured at low electric fields so that the influence of the Shottky effect could be neglected. Experiments were performed at both room and liquid nitrogen (LN2 ) temperatures. Basic idea & experimental details