Equations For Components Research Articles

Proof of Concept of a Low-Cost Beam-Steering Hybrid Reflectarray that Mixes Microstrip and Lens Elements Using Passive Demonstrators

In this article, a proof-of-concept study on the use of a hybrid design technique to reduce the number of phase shifters of a beam-scanning reflectarray (RA) is presented. An extended hemispherical lens antenna with feeds inspired by the retrodirective array is developed as a reflecting element, and the hybrid design technique mixes the lenses with the microstrip patch elements to realize a reflecting surface. Compared to the conventional designs that only use microstrip antennas to realize a reflecting surface, given a fixed aperture size the presented design uses 25 percent fewer array elements while shows comparable beam-steering performance. As a result of using fewer elements, the number of required phase shifters or other equivalent components such as RF switches and tunable materials is reduced by 25 percent, which leads to the reduction of the overall antenna system's complexity, cost, and power consumption. To verify the design concept, two passive prototypes with a center frequency at 12.5 GHz were designed and fabricated. The reflecting surface was fabricated by using standard PCB manufacturing and the lenses were fabricated using 3D printing. Good agreement between the simulation and measurement results is obtained. The presented design concept can be extended to the design of RAs operating at different frequency bands including millimetre-wave frequencies with similar radiation performances. The presented design method is not limited to the microstrip patch reflecting elements and can also be applied to the design of the hybrid RAs with different types of reflecting elements.

A new approach to investigate the ionic conductivity of NaCl and KCl solutions via impedance spectroscopy

Lima et al. [1] employed electrical impedance spectroscopy to analyze the electrical impedance behavior of dilute aqueous potassium chloride (KCl) and sodium chloride solutions in the frequency range of 10−1 Hz to 106 Hz (NaCl). The complex impedance Z* data from the solutions were modeled using an analogous electrical circuit that closely matched the experimental data. The electrical characteristics of the solutions were studied as a function of the cation types. The Debye model accurately describes the bulk effects of K+ and Na+ cations. However, it appeared that the analysis presented just the equivalent circuit components as a function of salt concentration. As a result, the current work used a simulation procedure to generate complex impedance (Z*) data from electrical parameters derived from the analogous circuit. To highlight the high-frequency relaxation processes occurring, extrapolation to a broader frequency range was performed. Furthermore, theoretical considerations were introduced in order to derive complex conductivity (σ*) from complex admittance (Y*). In the complex impedance (Z*) and admittance (Y*), there was a good correlation between all parameters derived from both processes. The key relaxation process characteristics, such as ionic strength, relaxation time, and conductivity values at low and high frequencies, were then retrieved. As a function of salt concentration, all of these parameters were evaluated and discussed.

Искусственный интеллект – освобождение человека от трудностей или его вытеснение?

The Artificial Intelligence systems have already become a reality. The work on their development is going very successfully, and therefore this reality requires monitoring and reflection, moreover, understanding not only how artificial intel­ligence can be developed, but also what the price can be, the consequences of the widespread use and applying of such technology. In the article, this theme is considered in the context of the work of K. Schwab, who put forward the idea that a new, Fourth, industrial revolution is beginning today. It is in this context that the phenomenon of AI and its applications is being raised and considered to­day. Therefore, the Fourth industrial revolution itself is considered in the row with other industrial revolutions that are singled out today. In the course of re­viewing the history of industrial revolutions, the author shows that now Schwab’s concept looks somewhat unfinished. The first three industrial revolutions have some main distinguishing features, the Fourth industrial revolution so far looks like it consists of equivalent components. In accordance with this, it is shown that the dominant discovery in the Fourth industrial Revolution is still present, and these are developments in the field of AI. An important question of the arti­cle is how to save people in the context of the industrial expansion of AI. In this regard, the theme of universal basic income discussed today is considered. Ac­cording to the author, this tool alone is not enough for people to go through the introduction of robots and AI painlessly. The author draws attention to the fact that people who are unemployed, but at the same time have a basic income, will be threatened by an overly comfortable home environment, leading to degradation.

Clinical and Refractive Outcomes of Toric Phakic Implantable Collamer Lens Implantation for correction of myopic astigmatism

Background: Currently there are four general approaches to correct refractive errors: refractive corneal surgery, crystalline lens surgery and implantation of an intraocular lens in anterior or posterior chamber. Aim: To evaluate the predictability, safety and stability of toric phakic implantable collamer lens implantation to correct moderate to high myopic astigmatism. Methods: Sixty eyes of 40 patients underwent implantation of a toric implantable collamer lens (V4c design) in the Eye Specialty Private Hospital, Baghdad, Iraq were studied. The mean spherical refraction was -11.32±3.17 diopter (D) with a range of -6.00 to -18.00 D and a mean cylinder of -2.61±1.16 with range of -1.00 to -5.50 D. The outcome measures that evaluated during a 12 months follow-up period include UDVA, refractive outcomes, CDVA, vault and adverse events. Results: At 12 months postoperatively, the mean Snellen decimal UDVA was 0.77±0.23 and the mean CDVA was 0.80±0.21, with an efficacy index of 1.16. Twenty nine eyes (48.33%) showed gain in CDVA with a safety index of 1.21. The treatment was highly predictable for spherical equivalent and astigmatic component. The mean SE dropped from -12.63±3.11 D to -0.11±0.20 D with 58 eyes within ±0.50 D and 60 eyes with ±1.00 D of the target correction. For achieved cylinder 60 eyes (100%) had ≤0.50 D and 51 eyes (85%) had ≤0.25 D with a strong positive linear correlation between achieved and expected cylinder (r=0.94). Conclusion: The results of the present study support safety, efficacy, predictability of toric implantable collamer lens implantation to treat moderate to high myopic astigmatism Abbreviation: UDVA: uncorrected distance visual acuity, CDVA: corrected distance visual acuity, SE: spherical equivalent and ACD: anterior chamber depth

Tissue dermal equivalent – а cellular product based on human dermal keratinocytes and fibroblasts: the properties of equivalent components and perspectives of practical application

The nature and ways of isolation and cultivation in vitro of keratinocytes and fibroblasts, the main cellular components of skin to prepare a new biomedical product, tissue dermal equivalent were considered. The main attention was payed to optimization of upbuilding dermal cell biomass including selection of medium compositions and conditions of cultivation. The information was given on main parameters of cell cultures as proliferation activity, viability and phenotype of the cells. Genotoxicity of fibroblasts and biocompatibility of the cells with organic matrixes to find the optimal carrier for cellular elements of tissue dermal equivalent were studied. The composition, the process of preparation of tissue dermal equivalent and perspectives of its practical application were discussed.

Design of Squirrel-Cage Self-Excited 3-phase Induction Generator

Due to the wide utilization of a 3-phase, squirrel-cage, self-excitation generator in renewable energy and isolated areas application, the paper deals with detailed design procedure of this type of generator, in a sequence and systematic manner. The design steps are obtained and executed in a Matlab file of the computer program to suit the newly designed constructions and parameters of the generator. In the new construction, the generator can be operated in a stable and saturation region. Due to the similarity in the construction of induction motor and generator, the formulas used in the calculation of equivalent circuit components of an induction motor may be utilized to calculate the parameters of the induction generator. To obtain optimized induction generator parameters and construction dimensions an ant colony algorithm is used to optimize these construction dimensions and generator parameters. The main objective parameters used in this algorithm are the generator efficiency, the excitation-capacitance, winding temperature rise, and minimum generator size is for 5 HP, 400 V, 50 Hz, and star connection generator.

Stepwise tracking strategy to screen ingredient from Galla Chinensis based on the “mass spectrometry guided preparative chromatography coupled with systems pharmacology”

Ethnopharmacological relevanceGalla chinensis, a traditional Chinese herbal medicine, was widely used to treat ulcerative colitis (UC) in folk prescriptions, however, its active ingredients and mechanism of action in the treatment of UC remain unclear. Aim of the studyThe aim of our study was to discover the lead compounds and anti-inflammatory active ingredients of Galla chinensis and clarify their molecular mechanism for UC treatment. Materials and methodsThe ingredients of Galla chinensis were prepared by column and mass spectrometry guided preparative chromatography. Besides, the relationship among the ingredients of Galla chinensis and targets was predicted by systems pharmacology. Additionally, Lipopolysaccharide (LPS)-induced RAW264.7 macrophages were used as in vitro model. The cell viability, the level of the pro-inflammatory factors, the generation of reactive oxygen species (ROS), and trans epithelial electric resistance (TEER) values were detected to screen out the active ingredients of Galla chinensis. Moreover, 4% dextran sodium sulfate (DSS)-induced ulcerative colitis mice were used as the UC animal model. The disease activity index (DAI), pathological degree of colon tissue, activities of antioxidant-related enzymes and expression level of pro-inflammatory cytokines were performed to assess the anti-UC effects of the active ingredients. Meanwhile, the mRNA expression level of inflammatory factors and antioxidant related genes were analyzed by real-time quantitative polymerase chain reaction (Q-PCR). And the expression of nuclear factor erythroid-2 related factor 2 (Nrf2) pathway related proteins, intestinal mucosal proteins and nuclear factor kappa-B (NF-κB) pathway related proteins in colon tissues were analyzed by Western Blotting. ResultsHerein, a stepwise tracking strategy was adopted to screen out the anti-inflammatory active ingredients of Galla Chinensis based on "preparative chromatography pharmacology combined with mass spectrometry guidance and system". 11 categories of ingredients of Galla chinensis were prepared and ethyl gallate (EG) was screened out the lead compound and anti-inflammatory active ingredient of Galla Chinensis through in silico, in vitro and in vivo studies. In addition, EG had a significant therapeutic effect on ameliorating DSS-induced UC mice and protected intestinal mucosal integrity through Nrf2 and NF-κB signaling pathway. ConclusionEthyl gallate was the lead compound and anti-inflammatory active ingredient in Galla chinensis. And it was discovered for the first time that EG could treat mice with ulcerative colitis. This research not only found the lead compound of Galla Chinensis for UC treatment and determined the possible mechanism, but also provided valuable references for finding lead compounds from natural products by systems pharmacology coupled with equivalent components group technology.

Modulation and Modeling of Three‐Dimensional Nanowire Assemblies Targeting Gas Sensors with High Response and Reliability

AbstractDespite improved sensitivity, simple downsizing of gas‐sensing components to randomly arranged nanostructures often faces challenges associated with unpredictable electrical conduction pathways. In the present study, controlled fabrication of three‐dimensional (3D) metal oxide nanowire networks is demonstrated that can greatly improve both signal stability and sensor response compared to random nanowire arrays. For example, the highest ever reported H2S gas response value, and a 5 times lower relative standard deviation of baseline resistance than that of random nanowires assemblies, are achieved with the ordered 3D nanowire network. Systematic engineering of 3D geometries and their modeling, utilizing equivalent circuit components, provide additional insights into the electrical conduction and gas‐sensing response of 3D assemblies, revealing the critical importance of wire‐to‐wire junction points and their arrangement. These findings suggest new design rules for both enhanced performance and reliability of chemical sensors, which may also be extended to other devices based on nanoscale building blocks.

The biomechanical profile of an osseo-integrated rectangular block implant: A pilot in vivo experimental study.

A novel implant design, the rectangular block implant (RBI), was investigated as a possible solution to the restoration of the posterior resorbed ridge. To maximally load test the osseo-integrated RBI in shear and tensile loads and relate these findings to known human masticatory loads as biomechanical proof of the study concept. Twelve RBIs were design-manufactured and placed into posterior mandibular saddles in 3mature greyhound dogs.-2 per left and right. After 12weeks of healing, osseo-integration was confirmed using resonance frequency analysis (RFA) and wrench torque tests. Three bone blocks each with two RBIs were dissected and mounted in acrylic. Micro-computerized tomography (μ-CT) was performed to assess bone to implant contact (BIC), and load analysis was performed using a Universal Test System. Three force applications were conducted until failure: pull-out (tensile), buccal push from the lingual (shear) and distal push from the mesial (shear). The osteotomy sites were examined using light magnification and scanning electron microscopy (SEM). Pull-out, buccal and distal force failures occurred at differing levels. Post-detachment sites showed complex patterns of bone failure, including trabecular and cortical fracture, as well as shearing at varying distances from the BIC. Interfacial shear strength was calculated at 14.4MPa. The osseo-integrated RBIs were able to withstand simulations of the demanding axially, bucco-lingually and mesio-distally oriented biomechanical challenges of the posterior saddle, under conditions of reduced bone volume. These values exceeded equivalent force components of maximal masticatory loads in humans.

Complex combined steroid mix of the female tract modulates human sperm

Human spermatozoa interact with a complex biochemical environment in the female reproductive tract en route to the site of fertilisation. Ovarian follicular fluid contributes to this complex milieu and is known to contain steroids such as progesterone, whose effects on sperm physiology have been widely characterised. We have previously reported that progesterone stimulates intracellular calcium concentration ([Ca2+]i) signalling and acrosome reaction in human spermatozoa. To characterise the effects of the unified complete follicular fluid steroid hormone complement on human spermatozoa, a comprehensive, data-based, ‘physiological standard’ steroid hormone balance of follicular fluid (shFF) was created from individual constituents. shFF induced a rapid biphasic [Ca2+]i elevation in human spermatozoa. Using population fluorimetry, we compared [Ca2+]i signal amplitude in cells exposed to serial applications of shFF (6 steps from 10-5X up to 1X shFF) with responses to the equivalent progesterone component alone (6 steps from 135 pM - 13.5μM). Threshold for the response to shFF was right-shifted (≈10-fold) compared to progesterone alone, but the maximum response to shFF was greatly enhanced. An acrosome reaction assay was used to assess functional effects of shFF-induced sperm calcium signalling. shFF as well as progesterone-treated spermatozoa showed a significant increase in % acrosome reaction (P < 0.01). All of this evidence suggests the modulation of progesterone-mediated responses by other follicular fluid steroids.

Parallel subgenome structure and divergent expression evolution of allo-tetraploid common carp and goldfish

How two subgenomes in allo-tetraploids adapt to coexistence and coordinate through structure and expression evolution requires extensive studies. In the present study, we report an improved genome assembly of allo-tetraploid common carp, an updated genome annotation of allo-tetraploid goldfish and the chromosome-scale assemblies of a progenitor-like diploid Puntius tetrazona and an outgroup diploid Paracanthobrama guichenoti. Parallel subgenome structure evolution in the allo-tetraploids was featured with equivalent chromosome components, higher protein identities, similar transposon divergence and contents, homoeologous exchanges, better synteny level, strong sequence compensation and symmetric purifying selection. Furthermore, we observed subgenome expression divergence processes in the allo-tetraploids, including inter-/intrasubgenome trans-splicing events, expression dominance, decreased expression levels, dosage compensation, stronger expression correlation, dynamic functionalization and balancing of differential expression. The potential disorders introduced by different progenitors in the allo-tetraploids were hypothesized to be alleviated by increasing structural homogeneity and performing versatile expression processes. Resequencing three common carp strains revealed two major ecotypes and uncovered candidate genes relevant to growth and survival rate.

Space Imaging Sensor Power Supply Filtering: Improving EMC Margin Assessment with Clustering and Sensitivity Analyses

This work is dedicated to the assessment of the filtering performances of an optoelectronic sensor for space applications. Particular care is taken concerning the power supply subsystem (here voltage shifter integrated circuit), which is part of the electromagnetic compatibility (EMC) compliance of an imaging equipment embedded on spacecrafts. The proposed methodology aims at two major targets: First, evaluating the Filter Effectiveness (FE) subject concerning varying parameters (including filter topology, parasitic effects and source/load impedance variations); second, quantifying the relative importance of representative equivalent electrical components through sensitivity analyses (nominal and parasitic values). The latter point is of utmost importance considering the expected versatility of such systems, such as manufacturing tolerances, for instance. Nominal values and/or components are often badly defined for confidentiality reasons, lack of knowledge or pure ignorance of inputs. An analytical deterministic formulation (here through the transfer matrix approach) is proposed and completed with an original stochastic strategy (Reduced Order Clustering, ROC). This ensures the reliable assessment of both statistical filter performances and most influential parameters, jointly with computational resources saving relatively to brute force Monte Carlo simulations.

Компьютерное моделирование сварки давлением образцов из гетерофазных никелевых сплавов через прослойку

Computer simulation of pressure welding of cylindrical workpieces through an interlayer was carried out using the DEFORM-2D software package in a two-dimensional formulation (axisymmetric deformation). Two combinations of materials to weld were considered: sample I — cylinders of heterophase nickel-based deformable superalloy EP975 in a coarse-grained state were welded through an interlayer of EP975 with a fine-grained microduplex structure; sample II — cylinders of dissimilar nickel-based alloys, one the deformable alloy EP975 in a coarse-grained state and the other an intermetallic alloy VKNA-25 with a single-crystal structure, were welded through an interlayer of EP975 alloy with a fine-grained microduplex structure. The welding process was carried out under isothermal conditions at a temperature of 1125°C and an initial strain rate of 10−4 s−1. The material characteristics were described by experimental curves obtained under uniaxial compression tests of alloys at the welding temperature. The Siebel friction model was used to describe the contact conditions on the surfaces to be welded. The friction coefficient was taken equal to 0.3. The distribution of equivalent, axial, radial, circumferential and shear components of stress and strain in the samples have been investigated. Analysis of the simulation results allowed one to conclude that, in comparison to welding of similar materials, during welding of dissimilar materials the values of the radial, axial and circumferential stresses increase. Radial and circumferential stresses in the material of the cylinders are tensile, while compressive stresses prevail in the material of the interlayer. Area with the maximum values of shear stresses in the region of contact between the cylinders and the interlayer also increases. In this case, axial, radial and circumferential strains decrease in a cylinder made from a material with higher strength, the overall level of shear strain does not change, and on the reciprocal contact surface of the interlayer, the region of extension of maximum shear strain extends to the entire contact zone. Such a combination of factors allows one to conclude on more favorable pressure welding conditions for welding of dissimilar alloys in comparison with similar materials.

The influence of the healing agent characteristics on the healing performance of epoxy coatings: Assessment of the repair process by EIS technique

The effects of the healing agents' molecular characteristics were studied on the self-healing performance of the epoxy coatings via corrosion evaluation techniques. Methylene diphenyl diisocyanate (kept constant) and different polyetheramine healing agents were encapsulated separately in poly(styrene-co-acrylonitrile) through the electrospray method and added to the epoxy matrix to prepare a polyurea-based dual capsule extrinsic healing system. Commercial grades of polyetheramine, Jeffamine D230, Jeffamine D400, and Jeffamine T403, were used to study the effects of molecular weight and functionality. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images revealed the formation of spherical shape with multicore morphology for the prepared polyetheramine containing microcapsules (MCs). Successful encapsulation was evaluated by Fourier transform infrared spectroscopy (FTIR), while the encapsulation yield was measured by thermogravimetric analysis (TGA). Electrochemical Impedance Spectroscopy (EIS) was employed to monitor the corrosion behaviour of a series of coated carbon steel samples through the evolution of the impedance spectra, and the numerical values of the related electrical equivalent circuit components (e.g., corrosion resistance), of the scratched coatings at different exposure times in a near-neutral 3.5 wt% NaCl solution. The results revealed the adverse effect on the corrosion protection ability by increasing the healing agent's molecular weight, while an increase of its functionality improved the final healing efficiency of the coating. According to the EIS results, the maximum healing efficiency was determined to be 85%, 72%, and 90% for Jeffamine D230, Jeffamine D400, and Jeffamine T403, respectively.

A randomized clinical trial using cyclopentolate and tropicamide to compare cycloplegic refraction in Chinese young adults with dark irises

BackgroundTo evaluate the necessity of cycloplegia for epidemiological studies of refraction in Chinese young adults (aged 17–22 years) with dark irises, and to compare the cycloplegic effects of 1% cyclopentolate and 0.5% tropicamide in them.MethodsA total of 300 young adults (108 males and 192 females) aged 17 to 22 years (mean 19.03 ± 1.01) were recruited from Tianjin Medical University from November 2019 to January 2020. Participants were randomly divided into two groups. In the cyclopentolate group, two drops of 1% cyclopentolate eye drop were administrated (one drop every 5 min), followed by autorefraction and subjective refraction 30 to 45 min later. In the tropicamide group, four drops of 1% Mydrin P (Tropicamide 0.5%, phenylephrine HCl 0.5%) eye drop were given (one drop every 5 min), followed by autorefraction and subjective refraction 20 to 30 min later. The participants and the examiners were masked to the medication. Distance visual acuity, intraocular pressure (IOP), non-cycloplegic and cycloplegic autorefraction (Topcon KR-800, Topcon Co. Tokyo, Japan), non-cycloplegic and cycloplegic subjective refraction and ocular biometry (Lenstar LS-900) were performed.ResultsThe values of spherical equivalent (SE) and sphere component were significantly different before and after cycloplegia in the cyclopentolate group and the tropicamide group (p < 0.05). The mean difference between noncycloplegic and cycloplegic autorefraction SE was 0.39 D (±0.66 D) in the cyclopentolate group and 0.39 D (±0.34 D) in the tropicamide group. There was no significant difference in the change of SE and sphere component after cycloplegia between the cyclopentolate group and the tropicamide group (p > 0.05). In each group, no significant difference was found between autorefraction and subjective refraction after cycloplegia (p > 0.05). We also found that more positive or less negative cycloplegic refraction was associated with the higher difference in SE in each group.ConclusionsCycloplegic refractions were generally more positive or less negative than non-cycloplegic refractions. It is necessary to perform cycloplegia for Chinese young adults with dark irises to obtain accurate refractive errors. We suggest that cycloplegic autorefraction using tropicamide may be considered as a reliable method for epidemiological studies of refraction in Chinese young adults with dark irises.Trial registrationThe study was registered on September 7, 2019 (Registration number: ChiCTR1900025774).

Formation of Orthogonal Components of Input Currents in Microprocessor Protections of Electrical Equipment

The methods used in the microprocessor protection of electrical equipment for forming orthogonal components of input currents ensure their reliable isolation after changing the mode followed by one or more periods of the fundamental frequency. This is due to the inertia of the functional elements, in particular, digital frequency filters, as well as the saturation of the steel magnetic cores of current transformers. To increase the speed of the selection of orthogonal components of the input currents, it is proposed to form them as equivalent ones in terms of the cosine and sine components obtained using digital Fourier filters by multiplying by the resulting coefficient. The method that has been developed for determining the specified coefficient provides compensation for the delay caused by the inertia of digital filters, as well as the saturation of the steel of magnetic cores of current transformers. The proposed method of forming orthogonal components is highly effective in the modes of strong saturation of the magnetic core with a complex input action in the presence of an aperiodic component with a large damping time constant. The evaluation of the efficiency of the proposed method was performed using a complex digital model implemented in the dynamic modeling environment MatLab-Simulink. As a result of the performed studies, it was found that in the absence of saturation of the magnetic core of current transformers, as well as in the presence of a small and medium degree of saturation, the proposed method for forming equivalent orthogonal components of input currents has dynamic properties close to the ones of those that had been previously proposed. With a strong saturation of the magnetic core of current transformers, the speed of obtaining reliable values of these components is increased by 1.5–2 times.

Electromagnetic effects of equatorially misaligned RF cavities

One of the most challenging problems in modern particle accelerator systems is the manufacture of RF cavities within the desired tolerance limits. In this study experimental and computational investigations to quantify the effects of transversal half-cell misalignments on the fundamental accelerator cavity parameters and beam dynamics are presented. Equivalent circuit components of an equatorially misaligned single-cell aluminum elliptical cavity are obtained from the measured data and are employed to calculate longitudinal impedance and modal wake function. Critical coupling and bead-pull measurements are performed at the TM010-like mode frequency, 2.45 GHz for the quality factor and shunt impedance of the high-β cavity. We report equivalent circuit analysis for higher-order modes and variations of the equivalent circuit components with respect to considered misalignment errors for the MICE experiment's muon cooling cavity. It is shown that using the equivalent circuit model decreases the computational load significantly for the wake field simulations of resonator cavities. Good agreement between simulations and measurements in terms of accelerating cavity parameters and impedances is illustrated.

Efficiency and Resource Implications of Food Losses and Waste in sub-Saharan Africa

Reducing the huge level of food losses and waste is arguably one of the sustainable ways of closing the food requirement gap in developing countries. Examining selected sub-Saharan Africa countries and utilizing the Food and Agriculture Organization of the United Nations’ Food Balance Sheet data, this study suggests that these countries lose over 29% (58.8 million tons) of the primary equivalent component of food. Exploiting the rich data on water and land footprints of food commodities, this study also identified considerable losses in resources – 21% of total water use and 15% of cropland use – associated with the food supply chain losses, with noticeable implications for agricultural sustainability.

Sodium borohydride (NaBH4) as a high-capacity material for next-generation sodium-ion capacitors

Abstract Energy storage is an integral part of the modern world. One of the newest and most interesting concepts is the internal hybridization achieved in metal-ion capacitors. In this study, for the first time we used sodium borohydride (NaBH4) as a sacrificial material for the preparation of next-generation sodium-ion capacitors (NICs). NaBH4 is a material with large irreversible capacity of ca. 700 mA h g−1 at very low extraction potential close to 2.4 vs Na+/Na0. An assembled NIC cell with the composite-positive electrode (activated carbon/NaBH4) and hard carbon as the negative one operates in the voltage range from 2.2 to 3.8 V for 5,000 cycles and retains 92% of its initial capacitance. The presented NIC has good efficiency &gt;98% and energy density of ca. 18 W h kg−1 at power 2 kW kg−1 which is more than the energy (7 W h kg−1 at 2 kW kg−1) of an electrical double-layer capacitor (EDLC) operating at voltage 2.7 V with the equivalent components as in NIC. Tin phosphide (Sn4P3) as a negative electrode allowed the reaching of higher values of the specific energy density 33 W h kg−1 (ca. four times higher than EDLC) at the power density of 2 kW kg−1, with only 1% of capacity loss upon 5,000 cycles and efficiency &gt;99%.

Special Aspects of Professional Activity of Motor Transport Profile Teaching Engineers

The article characterizes the special features of the motor transport profile teaching engineers’ professional activity in vocational institutions (teacher of vocational training, master of vocational training), higher education institutions (engineering teacher) and in manufacturing. &#x0D; The purpose is to clarify the special aspects of motor transport profile teaching engineers’ professional training in higher education institutions of Ukraine.&#x0D; The following research methods are used observation, description through individual interviews, expert evaluation method and questionnaire.&#x0D; The results are the following. It is stated that engineering and pedagogical education involves the rational integration of psychological, pedagogical and engineering components of professional training. It is noted that the professional training of teaching engineers is aimed at the formation their professional engineering and professional pedagogical competencies. This integrated training includes two equivalent integrated components: engineering (technical and technological, manufacturing, special, industrial branch) and pedagogical (humanitarian and social).&#x0D; It is stated that successful professional activity of a teaching engineer of motor transport profile is connected with professional training in institutions of higher education and the content and organization of their self-education in the process of professional development. To ensure proper training of a teaching engineer for successful activities, it is necessary to keep a continuous connection between the engineering and technical awareness and pedagogical activities. &#x0D; Modern professional activity of a teaching engineer is characterized by their innovative activities, the specifics of them is caused by the peculiarities of professional-pedagogical education and conditions of engineering-pedagogical activities, which provide generation and transformation of new ideas into innovations and form the management system. The innovative activity of teaching engineer is the basis of creative approach to professional responsibilities.&#x0D; It is concluded that a teaching engineer of motor transport profile is a teacher with higher pedagogical and technical education, who performs educational-methodical, engineering-technical, scientific-innovative, communicative-psychological, organizational, managerial and legal activities.