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Psychosocial risks associated with the profession of train driver
PublicationExcellent competencies as well as a good physical and mental health are required in train drivers’ profession. Despite the changes in the structure of employment the train drivers above 46 years and job tenure longer than 30 years are the largest group. The generation gap is becoming more pronounced, and its fulfilment will not be easy. It is related not only to training of new personnel but also promotion of healthy work environment...
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The Effectiveness of Basic Resuscitation Activities Carried out by Combat Paramedics of the Police, as Exemplified by Polish Counterterrorist Units
PublicationThe tasks carried out by Police officers are often accompanied by dangerous situations that threaten the life and health of the people involved, the police themselves, and bystanders. It concerns especially counter-terrorism police units whose activities are aimed at terrorists and particularly dangerous criminals, and their course is violent and aggressive. In conjunction with the inability to bring civilian rescue services into...
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Selected problems of experimental investigation of dynamically loaded journal bearings
PublicationIn the paper some problems concerning relations between external bearing loadings and critical lining stresses are described for test stand with rotating load vector. According to the standard ISO 7905/1 this type of test stand, for dynamically loaded slide bearing, is recommended as a basic research unit for material testing in a complete bearing unit. The lining stress calculation results occurred being dependent on applied calculation...
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Temperature-induced changes of HtrA2(Omi) protease activity and structure
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The Influence of Selected Parameters of Numerical Modelling on Strains and Stresses at Weld Toe Notch
PublicationLatest development in the field of welding technology and prefabrication enabled massive production of thin-walled sandwich structures. Multi-layered sandwich structures are fabricated with the use of high-power CO2 lasers, friction welding, arc welding, hybrid welding, or other technique designed for the special purpose. Steel or aluminium alloy plates with thickness between 1 and 5 mm are connected by internal stiffeners. Strength...
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Self Portrait with a Mask
PublicationPaweł SASIN - Self Portrait with a Mask “Every work of art is the child of its time, and, in many cases, the mother of our emotions. “ Wassily Kandynsky, Concerning the Spiritual in Art The two years 2020 and 2021 were marked by the COVID-19 pandemic – a lengthy period of time in which everyone felt in danger of losing one’s health or life. As a result, many people were experiencing negative emotion, becoming subject to psychological...
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An analysis of solar energy conversion systems based on photon and thermal processes
PublicationSolar spectral irradiance covers a fairly broad wavelength range. Solar radiation is part of the electromagnetic spectrum which is described by the concept of wave-particle duality. The corpuscular theory of electromagnetic radiation states that energy is transmitted by photons. Photons carry specific amounts of energy which can be used to convert solar energy into other types of energy, in particular electricity. The internal...
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The analysis of the determination of points positions using photogrammetric methods
PublicationThis article was created as a result of research conducted within the master thesis. The purpose of the research was to analyze the accuracy of determining the actual position of the photographed points according to the calculated parameters. The accuracy of photos alignment was determined as parameters, which determine their external and internal orientation. In order to determine the location of the determined points, it was...
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DESIGN OF THE DUAL CONSTELLATION GPS/GALILEO MOBILE DEVICE FOR IMPROVING NAVIGATION OF THE VISUALLY IMPAIRED IN AN URBAN AREA, POLISH MARITIME RESEARCH
PublicationThe article discusses damages of essential tribological associations in crankshaft and piston systems of large power two-stroke engines used as main engines, which take place during transport tasks performed by those ships. Difficulties are named which make preventing those damages impossible, despite the fact that the technical state of engines of this type is identified with the aid of complex diagnostic systems making use of...
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Interaction of amphotericin B and its selected derivatives with membranes: molecular modeling studies
PublicationJest to praca przeglądowa obejmująca krytyczną analizę danych dotyczących oddziaływania amfoterycyny B (AmB) i jej wybranych, mniej toksycznych pochodnych, z błonami lipidowymi. Amfoterycyna B jest antybiotykiem przeciwgrzybowym ale ze względu na jej toksyczność trwają prace nad modyfikacjami chemicznymi tego związku. Celem molekularnym dla tego antybiotyku jest błona lipidowa i dlatego różnicowe powinowactwo AmB i jej pochodnych...
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Molecular aspects of the interaction between amphotericin B and a phospholipid bilayer: molecular dynamics studies.
PublicationAmfoterycyna B jest antybiotykiem z grupy polienów makrolidowych. Stosowany jest on w leczeniu układowych infekcji grzybowych. Wiadomo że związek ten oddziałuje ze składnikami błon lipidowych i tworzy kanały. W przedstawianej pracy prezentowane są wyniki symulacji przeprowadzonej dynamiką molekularną układu składającego się z 200 cząsteczek lipidów DMPC i jednej cząsteczki amfoterycyny ułożonej na powierzchni błony. Z przeprowadzonej...
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Pomiary naprężeń w warstwie wierzchniej stali duplex metodą dyfrakcji promieniowania rentgenowskiego g-sin2Ψ = Residual stress measurements in duplex steel surface layers by g-sin2Ψ x-ray diffraction method
PublicationPrzedstawiono wyniki pomiarów naprężeń w warstwie wierzchniej z wykorzystaniem metody dyfrakcji promieniowania rentgenowskiego g-sin2. Wyjaśniono zasady przeprowadzania pomiarów naprężeń na próbkach walcowych o małej średnicy. Badania prowadzono na próbkach okrągłych ze stali duplex, poddanych procesom nagniatania. Stwierdzono występowanie naprężeń ściskających w warstwach powierzchniowych wszystkich badanych próbek oraz istotne...
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Approximate solution for Euler equations of stratified water via numerical solution of coupled KdV system
PublicationWe consider Euler equations with stratified background state that is valid for internal water waves. The solution of the initial-boundary problem for Boussinesq approximation in the waveguide mode is presented in terms of the stream function. The orthogonal eigenfunctions describe a vertical shape of the internal wave modes and satisfy a Sturm-Liouville problem. The horizontal profile is defined by a coupled KdV system which is...
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Innovations in family firms: a study of owner-managers’ knowledge development
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Persistent homology as a new method of the assessment of heart rate variability
PublicationHeart rate variability (hrv) is a physiological phenomenon of the variation in the length of the time interval between consecutive heartbeats. In many cases it could be an indicator of the development of pathological states. The classical approach to the analysis of hrv includes time domain methods and frequency domain methods. However, attempts are still being made to define new and more effective hrv assessment tools. Persistent...
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Temperature influences on shear stability of a nanosize plate with piezoelectricity effect
PublicationPurpose The purpose of this paper is to predict the mechanical behavior of a piezoelectric nanoplate under shear stability by taking electric voltage into account in thermal environment. Design/methodology/approach Simplified first-order shear deformation theory has been used as a displacement field. Modified couple stress theory has been applied for considering small-size effects. An analytical solution has been taken into account...
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Evaluation of reformer tubes degradation after long term operation
PublicationPurpose of this paper is to show the effect of long-term service at elevated temperatures on microstructural changes of cast steel reformer tubes made of the alloy IN-519 (24%Cr, 24%Ni, Nb). The relationship between mechanical properties and microstructure degradation is discussed. Investigations were performed on five tubes taken from ammonia reformer furnace. Tubes worked at temperature of 880C and 3,2 MPa pressure. The operation...
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Integrated dewatering and stabilization system as an environmentally friendly technology in sewage sludge management in Poland
PublicationSludge treatment reed beds (STRBs) are an environmentally friendly technology which provides integrated dewatering and stabilization of sewage sludge. STRBs do not require the use of chemicals to improve the dewatering process. STRB is both, a low-emission and a low-energy-consuming method. After the stabilization process, sludge is characterized by the chemical composition similar to that of humus. The aim of the paper is to present...
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GENERALISED HERSCHEL MODEL APPLIED TO BLOOD FLOW MODELLING
PublicationThis paper introduces a new rheological model of blood as a certain generalisation of the standard Herschel-Bulkley model. This model is a rheological constitutive equation and belongs to the group of the so-called generalised Newtonian fluids. Experimental data is compared with results, obtained from the new model, to demonstrate that it allows for the best agreement together with Luo-Kuang model. The new model may be easily implemented...
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Application of Structural Control Systems for the Cables of Cable-Stayed Bridges: State-of-the-Art and State-of-the-Practice
PublicationStay cables are one of the key elements of cable-stayed bridges and are characterized by lightweight, low inherent damping, and high flexibility. They are continuously subjected to small-to large-amplitude vibrations due to various types of dynamic loads that may, in the long term, cause fatigue and fracture problems for the cable system, and may eventually compromise the safety of cable-stayed bridges. Thus, several countermeasures...
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Friction and Lubrication of Large Tilting-Pad Thrust Bearings
PublicationFluid film bearings have been extensively used in the industry because of their unbeatable durability and extremely low friction coefficient, despite a very low coefficient of friction dissipation of energy being noticeable, especially in large bearings. Lubricating systems of large tilting pad thrust bearings utilized in large, vertical shaft hydrogenerators are presented in this paper. A large amount of heat is generated due...
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Natural radioactivity of solid and liquid phases from shale oil and gas prospection in Pomerania
PublicationIonizing radiation intensity data and estimation of equivalent absorbed dose from solid and liquid samples from prospection of shale gas and oil at selected sites in Pomerania are presented. Naturally occurring radioactive materials (NORM) are associated with geological formations or fluids and can be enhanced during oil and gas production. They appear in e.g. drilling cuttings, flow back water, produced water, scale and sludge....
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Navier number and transition to turbulence
PublicationThe motivation behind this article is to explain a role of the Navier number (Na -dimensionless slip-length) in prediction of closures for laminar to turbulent transition undergoing via eddies detachment from the slip layer in nano-cannals. Additionally the role of the Navier number Na in universal modeling of phenomenon of enhanced mass flow rate reported in micro- and nano-channels has been explained. The Na number should be...
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Investigation of praseodymium and samarium co-doped ceria as an anode catalyst for DIR-SOFC fueled by biogas
PublicationThe Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer. The XRD, SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore, the electrical...
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Hysteresis curves and loops for harmonic and impulse perturbations in some non-equilibrium gases
PublicationEvolution of sound in a relaxing gas whose properties vary in the course of wave propagation, is studied. A relaxing medium may reveal normal acoustic properties or be acoustically active. In the first case, losses in acoustic energy lead to an increase in internal energy of a gas similarly as it happens in Newtonian fluids. In the second case, acoustic energy increases in the course of sound propagation, and the internal energy...
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QUALITY GAPS IN HIGHER EDUCATION FROM THE PERSPECTIVE OF STUDENTS
PublicationThe presented research work relates to the category of quality in higher education. This article aims to present the determinants of the quality of education in the context of international standards. The background of the considerations is the Bologna Declaration and the European Higher Education Area. The results of the research carried out with the use of the nominal group method and the data analysis carried out based on the...
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Korozja i zniszczenia kształtowników stalowych o przekrojach zamkniętych
PublicationW artykule przedstawiono spotykany na obiektach budowlanych problem rozwoju korozji na wewnętrznych powierzchniach kształtowników zamkniętych eksploatowanych w środowisku zewnętrznym. Zachodzące wewnętrzne procesy korozyjne oraz towarzyszące im siły niszczące w związku z zamarzającą wewnątrz profili wodą, powodują utratę nośności i obniżenie bezpieczeństwa eksploatacji, przez co przyczyniają się do powstawania stanów awaryjnych....
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Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation
PublicationThe friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic...
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FAMILY INVOLVEMENT AND INNOVATION IN FAMILY ENTERPRISES
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Hydrodynamic model experiments with pod propulsors. Oceanic Eng. Intern.**2001 vol. 5 nr 2 s. 95-103, 15 rys. bibliogr. 6 poz. Hydrodynamiczne badania modelowe pędników azymutalnych.
PublicationPraca przedstawia badania modelowe trzech wariantów pędnika azymutalnego.Celem badań było zmierzenie charakterystyk hydrodynamicznych pędników w za-leżności od parametrów pracy oraz przeprowadzenie obserwacji kawitacji.
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Odpowiedzialność kierownicza w biznesie – zagadnienia procesowe i rodzajowe
PublicationCelem podjętych prac było przeprowadzenie rozważań nad zagadnieniami powstawania, ponoszenia, podejmowania oraz pociągania do odpowiedzialności kierowniczej. Kontynuacja badań nad odpowiedzialnością kierowniczą została oparta na sformułowanej wcześniej definicji. Umożliwiło to procesowe ujęcie przedmiotu eksploracji. W procesie tym wyróżniono fazy: przywołania, przyjęcia oraz poniesienia odpowiedzialności kierowniczej. Przeprowadzone...
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Assessing the failure of Open Government Data initiatives in Brazil
PublicationWhile assessing the potential of a particular digital innovation initiative, especially when it has implications for a range of societal stakeholders, it becomes pertinent to understand the possible bottlenecks in its acceptability as well. In this regard, the present study seeks to understand how the Open Government Data (OGD) initiatives in Brazil are being confronted with bottlenecks in terms of their execution and acceptability....
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Influence of the femoral offset on the muscles passive resistance in total hip arthroplasty
PublicationBackground Soft tissue tension is treated as a crucial factor influencing the post-THA dislocation. The femoral offset is regarded as one of the major parameters responsible for the stabilization of the prosthesis. It is unclear which soft tissue is mostly affected by the offset changes. Methods A finite element model of the hip was created. The model comprised muscles, bones, a stem, the acetabular component and a liner. The muscles...
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A general approach to study molecular fragmentation and energy redistribution after an ionizing event
PublicationWe propose to combine quantum chemical calculations, statistical mechanical methods, and photoionization and particle collision experiments to unravel the redistribution of internal energy of the furan cation and its dissociation pathways. This approach successfully reproduces the relative intensity of the different fragments as a function of the internal energy of the system in photoelectron–photoion coincidence experiments and...
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Właściwości mechaniczne tworzywa PET - przegląd literatury
PublicationThe article describes the influance of the microstructure and environment conditions on the mechanical properties of PET material. From the microskopic point of view, mechanical and thermal properties of PET material have the biggest influance on orientation and crystallization processes of material. From the macroskopic point of view mechanical properties can be described by parameters derived from strees-strain mechanical answers...
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Wavelet transform analysis to assess oscillations in pial artery pulsation at the human cardiac frequency
PublicationPial artery adjustments to changes in blood pressure (BP)may last only seconds in humans. Using a novelmethod called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) in humans, we aimed to assess the relationship between spontaneous oscillations in BP and cc-TQ at frequencies between 0.5 Hz and 5 Hz. We hypothesized that analysis of...
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Innovative activity of SMEs In Poland
PublicationInnovative activity of enterprises is determined by many factors. On one hand, these are external factors creating a sort of innovative climate in the economy, on the other hand - there are many internal factors stimulating or reducing the intensity of innovative activities. What influences the innovativeness of enterprises is the effectiveness of the system supporting innovations, which was stated by for example Pyciński and Żołnierski...
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Quantitative study of free convective heat losses from thermodynamic partitions using Thermal Imaging
PublicationThe following paper presents a simple method of determining the presence, distribution and values of heat losses from external building walls as thermodynamic partitions using a Thermal Imaging Camera (TIC). According to Fourier's equation, the value of heat loss is proportional to the temperature gradient ∂t/∂y|y=0 in air in the y direction perpendicular to the heated surface. Unfortunately, air temperature cannot be measured...
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Time-Gating method with automatic calibration for accurate measurements of electrically small antenna radiation patterns in Non-Anechoic environments
PublicationNon-anechoic sites represent a cheap alternative to measurements of antennas in dedicated facilities. However, due to a high noise—from the external EM signal sources and multipath interferences—the quality of radiation patterns obtained in non-anechoic conditions is poor. The characteristics can be corrected using a time-gating method (TGM), which involves filtering of the noise based on temporal analysis of the measured signals....
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Journey towards light – evolutionary adaptations of humans, flora and fauna. Guidelines for safe and healthy illumination
PublicationThe paper examines using relatively recent discoveries on how evolution has embedded within all living organisms a natural sensitivity towards their native environment, in particular luminance levels and specific wavelengths of light. The studies conducted so far indicate that lighting installations that are visible after dark impact on humans, flora and fauna and influence our evolutionary dispositions, possibly with negative...
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Tacit knowledge influence on intellectual capital and innovativeness in the healthcare sector: A cross-country study of Poland and the US
PublicationThis study provides empirical proof that whole organizational innovativeness is rooted in tacit knowledge due to its potency of human capital creation and, that a learning culture composed of a learning climate and mistakes acceptance component fosters human capital development. The main practical implication is that if the IC components are externally rather than internally determined in the particular organization embedded in...
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Do mistakes acceptance foster innovation? Polish and US cross-country study of tacit knowledge sharing in IT
PublicationAbstract Purpose – This study aims to understand and compare how the mechanism of innovative processes in the information technology (IT) industry – the most innovative industry worldwide – is shaped in Poland and the USA in terms of tacit knowledge awareness and sharing driven by a culture of knowledge and learning, composed of a learning climate and mistake acceptance. Design/methodology/approach – Study samples were drawn from...
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Direction-of-Arrival Estimation Methods in Interferometric Echo Sounding
PublicationNowadays, there are two leading sea sounding technologies: the multibeam echo sounder and the multiphase echo sounder (also known as phase-dierence side scan sonar or bathymetric side scan sonar). Both solutions have their advantages and disadvantages, and they can be perceived as complementary to each other. The article reviews the development of interferometric echo sounding array configurations and the various methods applied...
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Advances in analysis, quantification and modelling of N2O emission in SBRs under various DO set points
PublicationNitrous oxide (N2O), considered a major greenhouse gas (GHG) in wastewater treatment plants (WWTPs), is produced during both nitrification and denitrification processes; hence, it needs to be controlled by internal and external strategies. Various factors, such as DO, temperature, and pH, could be incorporated into the mitigation of emissions in WWTPs. In this research, potential operational strategies were investigated in order...
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CONDITIONS OF THE GREEN TRANSFORMATION. THE CASE OF THE EUROPEAN UNION
PublicationThe main purpose of the paper is to identify the factors that determine the course of green transformation and to assess the current stage and possible directions of change in subsequent years in EU countries. The literature lacks comprehensive studies that show the impact of diverse types of factors on the course of green transformation. For this purpose, two perspectives of the research – economic and environmental – are usually...
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Molecular modelling of membrane activity of amphotericin B, a polyene macrolide antifungal antibiotic
PublicationPraca dotyczy różnego typu modelowań molekularnych cząsteczki przeciwgrzybowego antybiotyku (amfoterycyny B). Praca przeglądowa obejmuje opis badań nad właściwościami molekularnymi samej cząsteczki antybiotyku, jej oddziaływań z powierzchnią błony oraz struktur kanałowych jakie tworzą cząsteczki amfoterycyny wewnątrz błony lipidowej.
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Theophylline Therapy for Near-Fatal Cheyne–Stokes Respiration: A Case Report
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On the Dynamics of a Visco–Piezo–Flexoelectric Nanobeam
PublicationThe fundamental motivation of this research is to investigate the effect of flexoelectricity on a piezoelectric nanobeam for the first time involving internal viscoelasticity. To date, the effect of flexoelectricity on the mechanical behavior of nanobeams has been investigated extensively under various physical and environmental conditions. However, this effect as an internal property of materials has not been studied when the...
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Electrochemical sensor for measurement of volatile organic compounds employing square wave perturbation voltage
PublicationThe paper presents the results of investigation on a prototype sensor for measurement of benzaldehyde in air. Sensitivity and limit of quantification of the sensor were determined for different internal electrolyte using the square wave voltammetry (SWV) as a detection technique. The working and counter electrodes were made of platinum. Ionic liquids 1-hexyl, 3-methylimidazolium chloride,1-hexyl, 3-methylimidazolium bis (trifluoromethanesulfonyl)...
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Pressure losses and power balance in the unloaded satellite pump
PublicationThis paper presents the results of laboratory research the pressure drop in the internal channels of unloaded satellite pump pumping tap water. Also shows the characteristics of the increase of pressure in the working chamber of the pump. It has been shown that after reaching cavitation, increase pump speed will increase in torque. This is the moment of inertia caused by the increase of the operating mechanism and the liquid contained...