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Search results for: MECHANISM OF AZOLE RESISTANCE
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Influence of operating pressure on the durability of a satellite hydraulic motor supplied by rapeseed oil
PublicationThis article describes the results of a durability test of a hydraulic satellite motor supplied by rapeseed oil. The tests were carried out on a test stand in a power recuperation system. The tests of the motor were carried out at a constant shaft speed for three fixed pressure drops in the motor. This made it possible to demonstrate the influence of the motor operating pressure on the durability of the satellite mechanism. The...
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Folding‐upon‐repair DNA nanoswitches for monitoring DNA repair enzymes activity
PublicationWe demonstrate here a new class of DNA‐based nanoswitches that, upon enzymatic repair, could undergo a conformational change mechanism leading to a change in fluorescent signal. Such folding‐upon‐repair DNA nanoswitches are synthetic DNA sequences containing O6‐methyl‐guanine (O6‐MeG) nucleobases and labelled with a fluorophore/quencher optical pair. The nanoswitches are rationally designed so that only upon enzymatic demethylation...
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Analysis of Failures of High Speed Shaft Bearing System in a Wind Turbine
PublicationDuring the operation of wind turbines with gearbox of traditional configuration, consisting of one planetary stage and two helical stages high failure rate of high speed shaft bearings is observed. Such a high failures frequency is not reflected in the results of standard calculations of bearing durability. Most probably it can be attributed to atypical failure mechanism. The authors studied problems in 1.5 MW wind turbines of...
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Hazardous material-related propagation of the effects of train accidents in the subgrade
PublicationA large part of the transport of hazardous materials is carried out by rail. Therefore, the security of these transports is becoming increasingly important. Every catastrophe involving dangerous materials has a negative impact on the participants of the incident and the surrounding environment, because its range is generally not local. It follows that in the event of a catastrophe, its effects should be minimized and remediation...
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Three electrode configuration measurements of electrolyte-diffusion barrier-cathode interface
PublicationMeasurements of a system consisting of cathode/doped ceria diffusion barrier/doped zirconia electrolyte were made using two- and three-electrode configuration. Results obtained on a three-electrode measurement configuration were compared with and reflect the results obtained in two-electrode configuration. Three-electrode measurements allowed separating the impact of the symmetrical interface in the investigated system. They also...
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Chemosensitization of multidrug resistant Candida albicans by the oxathiolone fused chalcone derivatives
PublicationThree structurally related oxathiolone fused chalcone derivatives appeared effective chemosensitizers, able to restore in part sensitivity to fluconazole of multidrug-resistant C.albicans strains. Compound 21 effectively chemosensitized cells resistant due to the overexpression of the MDR1 gene, compound 6 reduced resistance of cells overexpressing the ABC-type drug transporters CDR1/CDR2 and derivative 18 partially reversed fluconazole...
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Low cost set-up for supercapacitors parameters evaluation
PublicationWe propose a use of a power amplifier in the circuit of voltage to current converter (current driver) for supercapacitor charging/discharging in controlled conditions. The current driver is controlled by DAC output of DAQ board and voltage of DUT is measured and a control loop is realized by software. In the circuit the DC current method of evaluation of capacitance and equivalent series...
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The Influence of Gas Mixture in the Glow-Discharge Nitriding Process of Austenitic Stainless Steel on Characteristic of Nitrided Cases
PublicationAustenitic stainless steels characterize with excellent corrosion resistance, although low mechanical properties. In many cases that limits their exploitation in industrial applications. Moreover, austenitic stainless steel is susceptible to local corrosion in the presence of halide ions. In present works, it was emphasized that the nitriding of austenitic stainless steels gives some potential abilities to obtain beneficial effect...
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Analysis of the impact of wastewater discharge on recipients: synergistic approach
PublicationThe dissertation presents the analysis of chemical and microbial composition of wastewater and examines the impact of wastewater discharge on the environment. Various case studies were analysed: from small settlements in a pristine European Arctic, to large municipal wastewater treatment plants in areas subjected to greater anthropogenic pressure. In order to comprehensively analyse the impact of wastewater discharge on the receiving...
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Coupling between Blood Pressure and Subarachnoid Space Width Oscillations during Slow Breathing
PublicationThe precise mechanisms connecting the cardiovascular system and the cerebrospinal fluid (CSF) are not well understood in detail. This paper investigates the couplings between the cardiac and respiratory components, as extracted from blood pressure (BP) signals and oscillations of the subarachnoid space width (SAS), collected during slow ventilation and ventilation against inspiration resistance. The experiment was performed on...
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On analysis of nanocomposite conical structures
PublicationThis research examines the analysis of rotating truncated conical baskets reinforced by carbon nanotubes around the two independent axes. A time-dependent analysis is considered, and the nonlinear dynamic governing equations are extracted using the energy method. Carbon nanotubes (CNTs) reinforced the conical basket, and the structure's mechanical properties are determined based on the several distributions of carbon nanotubes....
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MATERIAŁY I ELEMENTY STOSOWANE DO WYKONANIA LEKKIEJ OBUDOWY cz. 1. Materiały metalowe
PublicationW artykule przedstawiono stosowane w lekkich obudowach materiały metalowe i kształtowane z nich wyroby. Omówiono charakterystyczne parametry i różnice technologiczne występujące w produkcji wyrobów. Przedstawiono ocenę odporności korozyjnej materiałów.
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Tailoring Graphene to Achieve Negative Poisson's Ratio Properties
PublicationGraphene can be made auxetic through the introduction of vacancy defects. This results in the thinnest negative Poisson's ratio material at ambient conditions known so far, an effect achieved via a nanoscale de-wrinkling mechanism that mimics the behavior at the macroscale exhibited by a crumpled sheet of paper when stretched.
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Cuticular lipids of insects as potential biofungicides
PublicationThe term ''lipids'' refers to fatty acids, their derivatives and substances related with them biochemically or by the functions in the body. Lipids include compounds with different chemical structure. There are lipids with structures based on long-chain carboxylic acids and their direct derivatives, namely: fatty acids, alkanes, some alkenes, aldehydes and long chain alcohols and their derivatives (esters). The variety of lipid...
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Dynamic impedance measurements of the Direct Methanol Fuel Cell cathode at various operating temperatures
PublicationThis article discusses the application of impedance analysis for diagnosing the cathode of a direct methanol fuel cell at various operating temperatures. The Dynamic Electrochemical Impedance Spectroscopy technique coupled with a linear current scan was applied for this purpose. This technique allowed the observation of changes in the cathode's properties in the fuel cell operating under real working conditions. An equivalent model...
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Synthesis and properties of porous Sr 0.96 Y 0.04 Ti 1−x Nb x O 3
PublicationA series of porous, single phase Sr0.96Y0.04Ti1-xNbxO3 samples was obtained using a wet synthesis method (modified citrate sol-gel) method. Temperature-programmed reduction (TPR) and temperature-programmed oxidation (TPO) measurements have shown high stability of the obtained material in variable (oxidizing/reducing) atmospheres. All samples exhibit high conductivity in hydrogen atmosphere with the highest value (around 1S/cm)...
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Influence of electropolymerization temperature on corrosion, morphological and electrical properties of PPy doped with salicylate on iron
PublicationIn this work, the influence of the electropolymerization temperature on corrosion, morphological and electrical properties of polypyrrole (PPy) film is studied. Polypyrrole is electrochemically synthesized on iron in the presence of sodium salicylate. The X-ray diffraction and scanning electron microscopy are performed in order to study the structure and morphology of electrodeposited PPy. The electroactive surface area, corrosion...
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New approaches for improving selectivity and sensitivity of resistive gas sensors: A review
PublicationResistive gas sensors are very popular and reliable but suffer from low selectivity and sensitivity. Various methods have been suggested to improve both features without increasing the number of sensors in gas detection systems. Fluctuation enhanced gas sensing was proposed to improve gas detection efficiency by analyzing low-frequency resistance fluctuations, and noise parameters can be more informative than the single DC resistance...
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Mechanical properties of sisal fiber-reinforced soybean oil-based polyurethane biocomposites
PublicationIn this paper the results of the mechanical properties of polyurethane biocomposites reinforced with short sisal fibers are presented. The fillers were added in different amount: 5, 10 and 15% by mass. Tensile test, hardness, abrasion resistance, elasticity were determined according to the standards.
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Mechanochemical Energy Transduction during the Main Rotary Step in the Synthesis Cycle of F1-ATPase
PublicationF1-ATPase is a highly efficient molecular motor that can synthesize ATP driven by a mechanical torque. Its ability to function reversibly in either direction requires tight mechanochemical coupling between the catalytic domain and the rotating central shaft, as well as temporal control of substrate binding and product release. Despite great efforts and significant progress, the molecular details of this synchronized and fine-tuned...
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Charge dependence of fragmentation process induced by ion collisions with furan molecule
PublicationThe goal of this work is to describe the system evolution after ion-molecule interaction. We combine different quantum chemistry and statistical mechanics approaches in order to give extended description of the process. Herein we report on a recent study of the fragmentation mechanism of neutral, singly- and doubly-ionized furan molecule in the gas phase.
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Improvement of derivatized amino acid detection sensitivity in micellar electrokinetic capillary chromatography by means of acid-induced pH-mediated stacking technique
PublicationDerivatization is a frequently used sample prepara-tion procedure applicable to the enhancement of analyte de-tection sensitivity. Amino acids mostly require derivatization prior to electrophoretic or chromatographic analysis, especial-ly if spectrophotometric detection is used. This study presents an on-line preconcentration technique for derivatized amino acids. The sensitivity of the method was improved by the utilization of...
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Softly Switched Robustly Feasible Model Predictive Control for Nonlinear Network Systems
PublicationIt is common that an efficient constrained plant operation under full range of disturbance inputs require meeting different sets of control objectives. This calls for application of model predictive controllers each of them being best fit into specific operating conditions. It further requires that not only designing robustly feasible model predictive controllers is needed to satisfy the real plant state/output constraints, but...
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Methods of liquid biofuels production - the bioethanol example.
PublicationEthanol is used in chemical and food industry, mainly either in the synthesis or as a solvent. The newest application of ethanol is as a fuel. This alcohol, produced on an industrial scale from crop waste, is widely known under the name bioethanol. It could be used as a fuel by itself or in a mixture with gasoline. Today, there are several technologies for bioethanol production known. The relatively simple method of obtaining bioethanol...
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METHODS OF LIQUID BIOFUEL PRODUCTION – THE BIOETHANOL EXAMPLE
PublicationEthanol is used in chemical and food industry, mainly either in the synthesis or as a solvent. The newest application of ethanol is as a fuel. This alcohol, produced on an industrial scale from crop waste, is widely known under the name bioethanol. It could be used as a fuel by itself or in a mixture with gasoline. Today, there are several technologies for bioethanol production known. The relatively simple method of obtaining bioethanol...
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Design of Intelligent Low-Voltage Load Switch for Remote Control System in Smart Grid
PublicationCurrent low-voltage load switches do not support remote disconnect/connect and real-time monitoring of a disconnect/connect state. Addressing to these issues, this paper presents a low-voltage load switch for a smart remote control system, which uses a one-chip microcontroller board and a DC step motor drive mechanism and provides the feedback on the switch status also. Arrears disconnect and full-pay connect control is implemented...
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Protective properties of Al2O3 + TiO2 coating produced by the electrostatic spray deposition method
PublicationMechanical resistance of Al2O3 + TiO2 nanocomposite ceramic coating deposited by electrostatic spray deposition method onto X10CrAlSi18 steel to thermal and slurry tests was investigated. The coating was produced from colloidal suspension of TiO2 nanoparticles dispersed in 3 wt% solution of Al2(NO3)3, as Al2O3 precursor, in ethanol. TiO2 nanoparticles of two sizes, 15 nm and 32 nm, were used in the experiments. After deposition,...
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Electrophoretic Deposition and Characterization of Chitosan/Eudragit E 100 Coatings on Titanium Substrate
PublicationCurrently, a significant problem is the production of coatings for titanium implants, which will be characterized by mechanical properties comparable to those of a human bone, high corrosion resistance, and low degradation rate in the body fluids. This paper aims to describe the properties of novel chitosan/Eudragit E 100 (chit/EE100) coatings deposited on titanium grade 2 substrate by the electrophoretic technique (EPD). The deposition...
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A global multinational survey of cefotaxime-resistant coliforms in urban wastewater treatment plants
PublicationThe World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this transnational study, we developed, validated, and tested a low-cost surveillance and...
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AUTOMATED SYSTEM FOR FLUCTUATION ENHANCED GAS SENSING
PublicationResistance gas sensors exhibit random phenomena (resistance noise) which can be utilized to improve gas sensitivity and selectivity. That new emerging technique has to be investigated to recognize optimal parameters for gas detection. It means that a measurement system has to have ability of numerous parameters adjustment (e.g., sampling frequency, heater voltage, polarization current, voltage noise amplification). That fact induced...
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Termooksydacyjna i fotooksydacyjna degradacja pianek poliuretanowych
PublicationPrzeprowadzono ocenę efektywności działania wybranych środków przeciwstarzeniowych w sztywnych piankach poliuretanowych, otrzymywanych na drodze syntezy jednoetapowej. Ocenę tę oparto na pomia-rach zmian barwy oraz wytrzymałości mechanicznej zsyntezowanych materiałów. Na podstawie analizy uzyskanych wyników stwierdzono, iż dodatek 3% mieszaniny I rzędowego antyutleniacza fenolowego oraz benzotriazolowego absorbera UV znacząco zmniejsza...
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Developing Materials for Biodegradable Otolaryngological Stents
PublicationMaterials for otolaryngological stents have to be characterized by good tensile strength, wear resistance, biocompatibility, and specific degradation time. This work aimed to synthesize polyurethanes based on various biodegradable polyol blends. Their biodegradability and mechanical properties were tested and compared to commercial BIOFLEX material.
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Cold recycled mixtures for binder courses - laboratory evaluation of mechanical properties
PublicationCold recycled mixtures composed with cement and bituminous emulsion are nowadays commonly used material for base layer. Typical pavement with cold recycled mixtures usually consists of two asphalt courses (wearing and binding course) constructed over cold recycled base. Therefore the next step in cold recycling is possibility of design of binding courses with recycled materials, but with potential to obtain high quality mixtures...
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Wpływ kształtu elektrody woltamperometrycznej na jej właściwości metrologiczne w dziedzinie czasu
PublicationW artykule omówiono właściwości metrologiczne elektrod woltamperometrycznych. Wykazano, że w przypadku oznaczania małych wartości stężeń jonów metali, elektrody te zachowują się tak jak przetworniki pomiarowe I rzędu. Ich właściwości metrologiczne opisuje czułość i stała czasowa. Wartości tych wielkości są uzależnione od mechanizmu transportu jonów do/od powierzchni elektrod oraz od ich kształtu. Wykonano symulacje wpływu kształtu...
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Microwave assisted liquefaction with crude glycerol as a potential method of brewer's spent grain utylization
PublicationBrewer's spent grain was applied as a low-cost industrial type of lignocellulose biomass in a liquefaction and solvent: biomass ratio on the efficiency of the process, chemical structure and basic properties of obtained prepared polyols and soil residues shed light on the biomass degradation mechanism through application of microwaves and further reaction of degradation products with solvent particles.
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Instantaneous impedance monitoring of synergistic effect between cavitation erosion and corrosion processes
PublicationThe most common method of determination of cavitation erosion resistance as well as the magnitude of erosion-corrosion synergistic interaction is based on the weight loss measurements. Nondestructive characterization of installations elements is in most cases impossible to perform. Also, such a measurement does not include local types of failure or alteration of operating conditions. There is an urge to elaborate a method for monitoring...
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The sensitivity of bacteria to heavy metals in presence of mineral ship motor oil in coastal marine sediments and waters.
PublicationThe sensitivity of bacteria, isolated from coastal marine sediments and waters of Sopot beach, Gdańsk Bay (Poland), to heavy metals in the presence of mineral ship motor oil were studied. All isolated heterotrophic bacteria were resistant to the 0.1 mM lead concentration occurring in the environment. Metal resistance of bacteria isolated from coastal water was strongly related to mineral ship motor oil concentration. At 0.1% mineral...
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Method of selecting the LS-SVM algorithm parameters in gas detection process
PublicationIn this paper we showed the method of resistive gas sensors data processing. The UV irradiation and temperature modulation was applied to improve gas sensors’ selectivity and sensitivity. Noise voltage across the sensor’s terminals (proportional to its resistance fluctuations) was recorded to estimate power spectral density. This function was an input data vector for LS-SVM (least squares – support vector machine) algorithm, which...
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Development of Microstructured Carbon Coatings by Substrate-Catalytic CVD
PublicationCarbon nanostructured films were synthesized by chemical vapor deposition (CVD) on H18 stainless steel (AISI 440C) sheets with an H2/CH4/N2 gas mixture at various substrate temperatures. During the synthesis, the iron and chromium oxide layer was formed between the steel and carbonaceous layer. The carbon films exhibited wall-like and spherical morphologies and structures, as characterized by scanning electron microscopy and Raman...
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Production and Properties of the Porous Layer Obtained by the Electrochemical Method on the Surface of Austenitic Steel
Publication: The growing demand for implants has seen increasing interest in the introduction of new technologies and surface modification methods of metal biomaterials. This research aimed to produce and characterize a porous layer grown on austenitic stainless steel 316L, obtained via the anodization process near the micro-arc oxidation, i.e., low voltage micro-arc oxidation (LVMAO). The discussed layer significantly influences the properties...
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Vessel Energy Requirement Prediction from Acceleration Stage Towing Tests on Scale Models
PublicationOne of the most crucial tasks for naval architects is computing the energy required to meet the ship’s operational needs. When predicting a ship’s energy requirements, a series of hull resistance tests on a scale model vessel is carried out in constant speed stages, while the acceleration stage measurements are ignored. Another important factor in seakeeping analysis is the ship’s hydrodynamic added mass. The second law of dynamics...
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Manganese Phosphatizing Coatings: The Effects of Preparation Conditions on Surface Properties
PublicationManganese phosphate coating could be used to protect the surface of steel products. However, it is essential to determine the effects which process parameters, as well as the types of additives used, have on the efficiency of coating deposition. Thus, we present here a process of phosphatization of low-alloy steel (for 15 min at 95 ◦C) in manganese/nickel baths followed by a passivation process with the use of a silicon and zircon...
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Electrophoretic co-deposition of Mn1.5Co1.5O4, Fe2O3 and CuO: Unravelling the effect of simultaneous addition of Cu and Fe on the microstructural, thermo-mechanical and corrosion properties of in-situ modified spinel coatings for solid oxide cell interconnects
PublicationA systematic microstructural, thermo-mechanical and electrical characterization of simultaneous Fe–Cu doped Mn–Co spinel coatings processed by electrophoretic co-deposition on Crofer 22 APU is here reported and discussed. An innovative approach for the simultaneous electrophoretic deposition of three spinel precursors is designed, conceived and optimised, with the aim of outlining time- and energy-saving spinel modification routes....
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Highly Oriented Zirconium Nitride and Oxynitride Coatings Deposited via High‐Power Impulse Magnetron Sputtering: Crystal‐Facet‐Driven Corrosion Behavior in Domestic Wastewater
PublicationHerein, highly crystalline ZrxNy and ZrxNyOz coatings are achieved by the deposition via high‐power impulse magnetron sputtering. Various N2 and N2/O2 gas mixtures with argon are investigated. The chemical composition and, as a result, mechanical properties of the deposited layer can be tailored along with morphological and crystallographic structural changes. The corrosion resistance behavior is studied by potentiodynamic measurements...
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Effects of Surface Pretreatment of Titanium Substrates on Properties of Electrophoretically Deposited Biopolymer Chitosan/Eudragit E 100 Coatings
PublicationThe preparation of the metal surface before coating application is fundamental in determining the properties of the coatings, particularly the roughness, adhesion, and corrosion resistance. In this work, chitosan/Eudragit E 100 (chit/EE100) were fabricated by electrophoretic deposition (EPD) and both their microstructure and properties were investigated. The present research is aimed at characterizing the effects of the surface...
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Phage therapy as a novel strategy in the treatment of urinary tract infections caused by E. coli
PublicationUrinary tract infections (UTIs) are regarded as one of the most common bacterial infections affecting millions of people, in all age groups, annually in the world. The major causative agent of complicated and uncomplicated UTIs are uropathogenic E. coli strains (UPECs). Huge problems with infections of this type are their chronicity and periodic recurrences. Other disadvantages that are associated with UTIs are accompanying complications...
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Tribo-Environment Dependent Chemical Modification of Sliding Interfaces in Ultrananocrystalline Diamond Nanowall Film: A Correlation with Friction and Wear
PublicationTribological properties of ultrananocrystalline diamond nanowall (UNCD NW) films were investigated quantitatively in three different and controlled tribo-environmental conditions, proposing the passivation and graphitization mechanisms. However, these mechanisms are rather complicated and possibly can be understood in well-controlled tribological conditions. It was shown that the friction and wear of these films were high in highPage 1...
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Wpływ zastosowania nakładek wzmacniających środnik na nośność i sztywność doczołowego węzła śrubowego.
PublicationCiągłe dążenie do upraszczania elementów konstrukcyjnych oraz znajdowania mniej czasochłonnych rozwiązań wykonawczo – montażowych wraz z nieuchronnym wzrostem kosztów robocizny determinują m.in. eliminację z procesów technologicznych tych etapów, które nie podlegają automatyzacji. Taką czynnością jest przede wszystkim spawanie dodatkowych wzmocnień i usztywnień węzłów w postaci żeber. Efektem wieloletnich badań jest metoda przedstawiona...
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Heat tint colours on stainless steel and welded joints
PublicationSurface layer condition of stainless steels and welded joints influences strongly their corrosion resistance. This problem seems to be underestimated. This current study explains the phenomenon of heat tint forming on welds, the methods of its removal, inspection procedures after heat tint removing and post weld finishing
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Badanie odporności na poślizg posadzkowych powłok żywicznych
PublicationW artykule przedstawiono badania wskaźnika szorstkości (odporności na poślizg) posadzki wykonanej z powłok żywicznych za pomocą wahadła angielskiego. Omówiono wybrane metody określania właściwości antypoślizgowych posadzek wraz z przeglądem literatury.