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A palatal prosthesis from archaeological research in the St Francis of Assisi church in Cracow (Poland)
PublicationThe hard palate is a septum that not only prevents food from entering between the oral and nasal cavity, but also plays an important role during breathing or speech. The presence of cavities within it negatively affects the comfort of life of people with this type of impairment. Hence, in the literature one can find examples of the use of hard palate prostheses to restore the separation between the nasal and oral cavity. During...
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Annealing Rate as a Crucial Parameter Controlling the Photoelectrochemical Properties of AuCu Mosaic Core–Shell Nanoparticles
PublicationThermal processing is an essential step during the synthesis of various metal nanostructures and for tailoring their morphology, optical, and electrochemical properties. Herein, a profound impact of the annealing rate and time on photoactivity of gold–copper nanostructures by changes in the position and alignment of energy levels and surface states is reported. AuCu nanoparticles (NPs) are fabricated by sputtering of thin metal...
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Study on Microstructural Characterization, Mechanical Properties and Residual Stress of GTAW Dissimilar Joints of P91 and P22 Steels
PublicationThis article deals with the dissimilar joining of two different grade Cr-Mo steel (2.25Cr-1Mo: P22 and modified 9Cr-1Mo: P91) for power plant application. The dissimilar butt-welded joint was produced for conventional V groove design by using the gas tungsten arc welding (GTAW) process with the application of an ERNiCrMo-3 Ni-based super alloy filler. A microstructure characterization was performed to measure the inhomogeneity...
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Powering the Future by Iron Sulfide Type Material (FexSy) Based Electrochemical Materials for Water Splitting and Energy Storage Applications: A Review
PublicationWater electrolysis is among the recent alternatives for generating clean fuels (hydrogen). It is an efficient way to produce pure hydrogen at a rapid pace with no unwanted by-products. Effective and cheap water-splitting electrocatalysts with enhanced activity, specificity, and stability are currently widely studied. In this regard, noble metal-free transition metal-based catalysts are of high interest. Iron sulfide (FeS) is one...
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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublicationNew products of photo- and thermal rearrangements of 19-membered azoxybenzocrown with phenyl substituents in benzene rings in the para positions to oligooxyethylene fragments are characterized. The yields of photochemical transformations depend on the solvent. Para-hydroxyazocrown is formed with yields over 50% in propan-2-ol. Ortho-hydroxyazobenzocrown is obtained with yields up to 70% in toluene/acetic acid mixture. Macrocyclic...
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Azo and azoxythiacrown ethers: synthesis and properties
PublicationA series of 16- and 18-membered azo- and azoxythiacrown ethers have been synthesized by reductive macrocyclization of the respective bis(nitrophenoxy)oxaalkanes. The aromatic residues located in the polyether region of the molecule were introduced to macrocyclic skeletons and their affinities toward different groups of metal cations in ion-selective electrodes were described. X-ray structures for one dinitropodand and one azoxybenzothiacrown...
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Determining the leakage current resistive component by the orthogonal vector method
PublicationThe measurement of the metal – oxide surge arresters (MOSA) leakage current and the analysis of its components is a key diagnostic criterion according to technical standards. During on site MOSA condition assessment, the easy way is based on the measurement only leakage current, without the inconvenient live working measurements of supply voltage. Orthogonal vectors method of determination the resistive leakage current is presented....
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THE USE OF THE Ti-13Zr-13Nb ALLOY POWDER FOR MANUFACTURING OF PROSTHETIC PARTS BY SELECTIVE LASER MELTING
PublicationThe 3D printing is a manufacturing technique belonging to the additive methods able to prepare the designed parts for various purposes. The present reasearch was aimed to fabricate the prosthetic foundations and bridges made of the new Ti-13Zr-13Nb alloy by the selective laser melting (SLM) of a metal powder. The scanning electron examinations and micro scanning tomography were used to investigate the surface quality and intrinsic...
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Activity of Polish unifloral honeys against pathogenic bacteria and its correlation with colour, phenolic content, antioxidant capacity and other parameters.
PublicationThe use of honey as an antimicrobial agent gains importance due to often ineffectiveness of conventional treatment. However, activity of honey depends mainly on its botanical and geographical origin. To date, antimicrobial potential of Polish honeys has not yet been entirely investigated. In this study, 37 unifloral samples of 14 honey types (including rare varieties) from Poland were analysed and compared with manuka honey. The...
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The Effect of Welding Conditions on Mechanical Properties of Superduplex Stainless Steel Welded Joints
PublicationThe tests results of superduplex stainless steel welded joints made with a different heat input, using automatic submerged arc welding (SAW) and semi-automatic flux-cored arc welding (FCAW) have been presented. Metallographic examinations, the measurements of the ferrite content, the width of the heat affected zone (HAZ) and the hardness of the welds in characteristic areas have been performed. Significant differences in the amount of...
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Inhibition of impurities formation in the synthesis of N-alkyltheobromines stimulated by microwave irradiation. Cationic and anionic response of membrane electrodes
PublicationN-Alkyltheobromine (1-9) derivatives were obtained by reacting theobromine with appropriate alkyl halide under microwave irradiation at 100-150 W and by conventional synthesis. Formation of by-products of oxygen atom alkylation and 1-N-alkyltheobromine ring opening were considered. The presented compounds 1-5 have been studied as ion carriers in ion-selective membrane electrodes. Selectivity of these membranes was studied towards...
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Novel Biomass-Based Polymers: Synthesis, Characterization, and Application
PublicationA wide range of polymers were prepared from biomass-derivatives, using different polymerization mechanisms. Well-defined, fully hydroxy-functional polyesters based on aliphatic diols were synthesized, using either conventional metal-based catalysts or the organic superbase 1,5,7-triazabicyclododecene (TBD). Unsaturated polyesters were also made, offering additional functionality to these biobased resins. Metal-catalyzed or enzymatic...
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Ionic liquids for nano- and microstructures preparation. Part 1: Properties and multifunctional role
PublicationIonic liquids (ILs) are a broad group of organic salts of varying structure and properties, used in energy conversion and storage, chemical analysis, separation processes, as well as in the preparation of particles in nano- and microscale. In material engineering, ionic liquids are applied to synthesize mainly metal nanoparticles and 3D semiconductor microparticles. They could generally serve as a structuring agent or as a reaction...
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Ongoing progress on novel nanocomposite membranes for the separation of heavy metals from contaminated water
PublicationMembranes, as the primary separation element of membrane-based processes, have greatly attracted the attention of researchers in several water treatment applications, including wastewater treatment, water purification, water disinfection, toxic and non-toxic chemical molecules, heavy metals, among others. Today, the removal of heavy metals from water has become challenging, in which chemical engineers are approaching new materials...
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Ball milling treatment of Mn3O4 regulates electron transfer pathway for peroxymonosulfate activation
PublicationHeterogeneous metal catalysts have attracted considerable interest in advanced oxidation processes (AOPs) for wastewater treatment by activating peroxymonosulfate (PMS). However, it remains challenging to the rational design of efficient reaction pathway for high-performance contaminants removal by regulating the inherent structure of metal oxides. Herein, a high-energy ball milling method was employed to modulate the electronic...
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MOF/TiO2 erythrocyte-like heterostructures decorated by noble metals for use in hydrogen photogeneration and pollutant photodegradation
PublicationVarious metal–organic framework (MOF)/TiO2 heterostructures can be obtained by the partial hydrolysis or calcination of Ti-based MOFs. By adjusting the hydrolysis and calcination steps of NH2-MIL-125 (Ti), a novel photoactive material composed of a MOF (NH2-MIL-125 (Ti)) and TiO2, with a unique “erythrocyte” shape, was developed. Furthermore, modification of the composition prepared by the partial hydrolysis of NH2- MIL-125 (Ti)...
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A new strategy for PET depolymerization: Application of bimetallic MOF-74 as a selective catalyst
PublicationLarge-volume production of poly(ethylene terephthalate) (PET), especially in the form of bottles and food packaging containers, causes problems with polymer waste management. Waste PET could be recycled thermally, mechanically or chemically and the last method allows to obtain individual monomers, but most often it is carried out in the presence of homogeneous catalysts, that are difficult to separate and reuse. In view of this,...
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X-Ray Computer Tomography Study of Degradation of the Zircaloy-2 Tubes Oxidized at High Temperatures
PublicationThe investigations of high-temperature oxidation of zirconium alloys, applied for fuel pellets in nuclear power plants, are usually limited to oxidation kinetics, phase transformations and microstructural characterization. The purpose of this research was to characterize the degradation phenomena occurring within oxide layer and at the interface oxide/metal, on internal and external Zircaloy-2 tube...
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Monitoring Lead Concentration in the Surrounding Environmental Components of a Lead Battery Company: Plants, Air and Effluents—Case Study, Kenya
PublicationLead (Pb) pollution from smelters and lead–acid battery has become a serious problem worldwide owing to its toxic nature as a heavy metal. Stricter regulations and monitoring strategies have been formulated, legislated and implemented in various parts of the world on heavy metal usage. Developed countries such as the USA and in Europe largely operate within the set standards, however, developing countries such as Kenya, Nigeria...
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Study of the anticancer potential of Cd complexes of selenazoyl-hydrazones and their sulfur isosters
PublicationThe biological activity of Cd compounds has been investigated scarce since Cd has been recognized as a human carcinogen. However, the toxicity of cadmium is comparable to the toxicity of noble metals such as Pt and Pd. The paradigm of metal toxicity has been challenged suggesting that metal toxicity is not a constant property, yet it depends on many factors like the presence of appropriate ligands. Studies on anticancer activity...
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Determining pesticide contamination in honey by LC-ESI-MS/MS - Comparison of pesticide recoveries of two liquid-liquid extraction based approaches
PublicationHoney, a valuable food product, may be contaminated by xenobiotics during its production and/or harvest. The determination of trace levels of contaminants in a complex matrix like honey still presents a challenge to analytical chemists. The aim of this work was to assess and compare the extraction efficiencies of 30 pesticide residues (acaricides, insecticides, herbicides, fungicides), belonging to over 15 different chemical classes....
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Levels of 13 multi-class pesticide residues in Polish honeys determined by LC-ESI-MS/MS
PublicationLevels of 13 pesticides in 40 honey samples form Poland are reported. A rapid and sensitive method was developed for the LC-ESI-MS/MS determination of multi-class pesticide residues in honey samples. Liquid-liquid extraction (LLE) on a diatomaceous earth support (requiring the use of small amounts of organic solvent), followed by chromatographic separation on a C18 column and gradient elution were employed. The method quantifies...
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A Novel Approach to Fully Nonlinear Mathematical Modeling of Tectonic Plates
PublicationThe motion of the Earth's layers due to internal pressures is simulated in this research with an efficient mathematical model. The Earth, which revolves around its axis of rotation and is under internal pressure, will change the shape and displacement of the internal layers and tectonic plates. Applied mathematical models are based on a new approach to shell theory involving both two and three-dimensional approaches. It is the...
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Comparison of direct and inverse methods of satellite observations downscaling for the coastal zone area
PublicationThe Earth observation satellite imaging systems have known limitations, especially regarding their spatial and temporal resolution. Therefore, approaches which aim to combine data retrieved from sensors of higher temporal and lower spatial resolution with the data characterized by lower temporal but higher spatial resolution are of high interest. This allows for joint utilization of the advantages of both these types of sensors....
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Agent-based social network as a simulation of a market behaviour
PublicationRecent years and the outbreak of world's economic crisis in 2008 proved the crucial importance of reliable analysis of market dynamics. However, werarely apply models of proper detail level (the global prosperity forecast of 2007 can be seen as a grim proof). The behaviour of individuals and companies is far from being ideal and rational. Many claims that the economic paradigm of rational expectations (coming from J. Muth and R....
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Badania stanu technicznego ścianek szczelnych strony południowej i północnej komory południowej śluzy Dzierżno
PublicationPrace dotyczyły badań nieniszczących łączników (zamków) Paine`a oraz ścianek szczelnych. Ściany boczne komory południowej śluzy Dzierżno zbudowane są ze stalowych pasów blachy o grubości około 16mm i długości 22m połączonych ze sobą wzdłuż dłuższej krawędzi za pomocą zamków Peine`a. System ten umożliwia uzyskanie szczelnego połączenia na całej długości ścianki. Zaawansowany proces korozji spowodował rozszczelnienie połączenia...
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THE EFFECT OF WET UNDERWATER WELDING ON COLD CRACKING SUSCEPTIBILITY OF DUPLEX STAINLESS STEEL
PublicationABSTRACT The present work was conducted to assess the weldability of duplex stainless steel in underwater conditions. Metal manual arc welding (MMA) with the use of coated electrodes was used in the investigations. Tekken weldability tests were performed underwater at 0.5 m depth and in the air. Nondestructive tests, metallographic examinations of welds, ferrite content assessment in microstructure and hardness test were performed....
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Chromogenic derivatives of new bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) - synthesis and properties
PublicationDerivatives of bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) with oxygen and sulphur atoms in the structure of aliphatic chains were successfully synthesised. The correlation between the ligand structure and its complexation properties was investigated by absorption spectroscopy. The formation of complexes of presented compounds with metal cations (Cu2+, Ni2+, Zn2+, Co2+, Fe2+ and Pb2+) was studied. Ligands 5-8 were additionally...
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Principles and applications of Ligation Mediated PCR methods for DNA-based typing of microbial organisms
PublicationA significant number of DNA-based techniques has been introduced into the field of microorganisms’ characterization and taxonomy. These genomic fingerprinting methods were developed to detect DNA sequence polymorphisms by using general principles, such as restriction endonuclease analysis, molecular hybridization, and PCR amplification. In recent years, some alternative techniques based on ligation of oligonucleotide adapters before...
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Tuning the ferromagnetic phase in the CDW compound SmNiC2 via chemical alloying
PublicationWe report a study on tuning the charge density wave (CDW) ferromagnet SmNiC2 to a weakly coupled superconductor by substituting La for Sm. X-ray diffraction measurements show that the doped compounds obey Vegard’s law, where La (Lu) alloying expands (shrinks) the lattice due to its larger (smaller) atomic size than Sm. In the series Sm1−xLaxNiC2, CDW transition (TCDW =148K) for SmNiC2 is gradually suppressed, while the ferromagnetic...
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Cast Iron Staircase in Aleksandrów Kujawski (Poland) - History, Construction, Architectural Form
PublicationThe text presents historic cast iron staircase, which is situated inside the railway station building in Aleksandrów Kujawski. Since the moment of creation in the 19th century for a long time that station, located at the border of Prussia and Kingdom of Poland, was an important transit point. Nowadays it is situated in the central of Poland. The staircase was built in 1870’s as a result of an extension of the railway station building...
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3,3'-Dibenzoyl-1,1'-dibenzyl-1,1'-(ethane-1,2-diyl)dithiourea
PublicationIn the title compound, C32H30N4O2S2, the carbonyl and thiocarbonyl groups are found in a rare synclinal conformation, with an S-C···C-O pseudo-torsion angle of 62.6(2)°. The molecule has Ci = S2 point-group symmetry with a crystallographic center of inversion located in the middle of the ethylene bridge. One of the symmetry-independent phenyl...
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Noncentrosymmetric Triangular Magnet CaMnTeO6: Strong Quantum Fluctuations and Role of s0 versus s2 Electronic States in Competing Exchange Interactions
PublicationNoncentrosymmetric triangular magnets offer a unique platform for realizing strong quantum fluctuations. However, designing these quantum materials remains an open challenge attributable to a knowledge gap in the tunability of competing exchange interactions at the atomic level. Here, a new noncentrosymmetric triangular S = 3/2 magnet CaMnTeO6 is created based on careful chemical and physical considerations. The model material...
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Results from a Genome-Wide Association Study (GWAS) in Mastocytosis Reveal New Gene Polymorphisms Associated with WHO Subgroups
PublicationMastocytosis is rare disease in which genetic predisposition is not fully understood. The aim of this study was to analyze associations between mastocytosis and single nucleotide polymorphisms (SNPs) by a genome-wide association study (GWAS) approach. A total of 234 patients were enrolled in our study, including 141 with cutaneous mastocytosis (CM; 78 children and 63 adults) and 93 with systemic mastocytosis (SM, all adults)....
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Partitioning of heavy metals in sub-surface flow treatment wetlands receiving high-strength wastewater
PublicationThe retention of heavy metals at two pilot-scale treatment wetlands (TWs), consisting of two vertical flow beds (VSSF) followed by a horizontal flow bed (HSSF) was studied. The TWs received highstrength wastewater: reject waters from sewage sludge centrifugation (RW) and landfill leachate (LL). The concentrations of metals: Fe, Mn, Zn, Al, Pb, Cu, Cd, Co, Ni were measured in treated wastewater, substrate of the beds and in plant...
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A new B-D-galactosidase with a low temperature optimum isolated from the Antarctic Arthrobacter sp. 20B: gene cloning, purification and characterization.
PublicationA psychrotrophic bacterium producing a coldadaptedB-galactosidase upon growth at low temperatureswas classiWed as Arthrobacter sp. 20B. A genomic DNAlibrary of strain 20B introduced into Escherichia coliTOP10F' and screening on X-Gal (5-bromo-4-chloro-3-indolyl-B-D-galactopyranoside)-containing agar plates ledto the isolation of B-galactosidase gene. The B-galactosidasegene (bgaS) encoding a protein of 1,053 amino acids,with a...
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THE ANALYSIS OF THE INFLUENCE OF STRESS DISTRIBUTION ON WEAR PROFILE IN LUBRICATED SLIDING CONTACT OF UHMW-PE VS TITANIUM Ti-13Nb-13Zr ALLOY
PublicationMetal – polymer sliding contacts are a typical combination in industry and medicine. For decades such a set of materials has been the primary choice in human joints endoprosthetic technology. In this paper tribological issues of are presented from a research on the potential for practical use of Ti-13Nb-13Zr/UHMW-PE couple for orthopedic endoprosthesis. In tests on simplified models it is critically important to carefully...
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Artificial neural network prophecy of ion exchange process for Cu (II) eradication from acid mine drainage
PublicationThe removal of heavy metal ions from wastewater was found to be significant when the cation exchange procedure was used effectively. The model of the cation exchange process was built using an artificial neural network (ANN). The acid mine drainage waste’s Cu(II) ion was removed using Indion 730 cation exchange resin. Experimental data from 252 cycles were recorded. In a column study, 252 experimental observations validated the...
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Catalytic Activity of Nickel and Ruthenium–Nickel Catalysts Supported on SiO2, ZrO2, Al2O3, and MgAl2O4 in a Dry Reforming Process
PublicationDry reforming of methane (DRM) is an eco-friendly method of syngas production due to the utilization of two main greenhouse gases—methane and carbon dioxide. An industrial application of methane dry reforming requires the use of a catalyst with high activity, stability over a long time, and the ability to catalyze a reaction, leading to the needed a hydrogen/carbon monoxide ratio. Thus, the aim of the study was to investigate the...
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Cu( II ) ions removal from wastewater using starch nanoparticles ( SNPs ): An Eco‐sustainable approach
PublicationThe complex structured starch particles were reduced to the nanoscale size range through hydrolysis utilizing low concentration acid assisted with ultrasound irradiation. The synthesized starch nanoparticles (SNPs) were characterized by TEM, FTIR, and XRD techniques. The synthesized SNPs possessed surface activated entities, as many cationic functional groups were confirmed through the FTIR spectrum. Also, these SNPs were effectively...
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Electrochemistry from first-principles in the grand canonical ensemble
PublicationProgress in electrochemical technologies, such as automotive batteries, supercapacitors, and fuel cells, depends greatly on developing improved charged interfaces between electrodes and electrolytes. The rational development of such interfaces can benefit from the atomistic understanding of the materials involved by first-principles quantum mechanical simulations with Density Functional Theory (DFT). However, such simulations are...
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The abrasive wear resistance of coatings manufactured on high-strength low-alloy (HSLA) offshore steel in wet welding conditions
PublicationSome marine and offshore structure elements exploited in the water cannot be brought to the surface of the water as this will generate high costs, and for this reason, they require in-situ repairs. One of the repair techniques used in underwater pad welding conditions is a wet welding method. This paper presents an investigation of the abrasive wear resistance of coatings made in wet welding conditions with the use of two grades...
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Selected organophosphorus compounds with biological activity. Applications in medicine
PublicationThe purpose of this article is to provide an overview of the latest applications of organophosphorus compounds (OPs) that exhibit biological activity. A large family of OPs have become popular in recent years. The practical application of OPs in modern medicine has been attributed to their unique properties. In this article, the methods used to select these compounds will be emphasized. This paper will first outline the findings...
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Assessment of copper surface coverage with corrosion inhibitor using AFM-based local electrical measurements
PublicationThe paper presents a new method of assessment of metal surface coverage with corrosion inhibitor and thus of inhibitor protective performance. It is based on the atomic force microscopy measurement performed in a contact mode. Apart from topography images the proposed approach allows acquisition of local DC maps and local electrical impedance spectra via application of DC bias voltage or AC perturbation signal between the conductive...
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9 - Solid oxide fuel and electrolysis cells
PublicationIn this chapter, the fundamental reactions, the geometrical designs, the material requirements, and the status of SOFCs and SOECs are presented. In the following seven chapters, the most important components of an SOC are described and the chapter ends with a summary and outlook. The described components are: (i) oxygen-ion conductors (electrolyte), (ii) anode materials for SOFCs (cathode in SOEC mode), (iii) cathode materials...
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Influence of the air phase on water flow in dikes
PublicationNumerical models are often used to describe flow and deformation processes occurring in dikes during flood events. Modeling of such phenomena is a challenging task, due to the complexity of the system, consisting of three material phases: soil skeleton, pore water and pore air. Additional difficulties are transient loading caused by variable in time water levels, heterogeneity of the soil or air...
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Bacterial presence in polar regions associated with environment modification by chemical compounds including contaminants
PublicationMicrobes are omnipresent and diverse members of all biological communities. In marine and freshwater ecosystems, microorganisms form the base of the food chain supporting higher trophic levels. Even though, microbes generally are thought to live in warm regions of Earth, many of them develop in cold climates. Polar regions remain relatively protected from widespread anthropogenic disturbances, which is a consequence of its remoteness...
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Preparation and characterization of asphaltene based adsorbents for gas-solid adsorption systems
PublicationThe dissertation presents results of the experimental research on asphaltene-based adsorbents (support coated with asphaltene layer) for gas-solid adsorption systems, with special reference to volatile organic compounds (VOCs) removal from gas streams. Analysis of gas adsorption properties revealed that asphaltenes isolated from oxidized bitumen have strong affinity toward VOCs. Interactions with target gas molecules, and selectivity...
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Behavior of residual current devices at frequencies up to 50 kHz
PublicationThe use of residual current devices (RCDs) is obligatory in many types of low-voltage circuits. They are devices that ensure protection against electric shock in the case of indirect contact and may ensure additional protection in the case of direct contact. For the latter purpose of protection, only RCDs of a rated residual operating current not exceeding 30 mA are suitable. Unfortunately, modem current-using equipment supplied...
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Novel single-stranded DNA-binding protein from psyvhrophilic bacterium Psychrobacter arcticus
PublicationTo study the biochemical properties of SSB from Psychrobacter arcticus (ParSSB), we have cloned the ssb genes obtained by PCR and have developed Escherichia coli overexpression systems. The gene consists of an open reading frame of 642 nucleotides encoding SSB protein of 213 amino acids with a calculated molecular mass of 22.8 kDa. The amino-acid sequence of ParSSB exhibits 49% identity and 57% similarity to Escherichia coli SSB....