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Wyniki wyszukiwania dla: BINARY METAL OXIDE
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Oxidation and hydrogen behavior in Zr-2Mn alloy
PublikacjaThe purpose of the present research was to determine the oxidation and hydrogenation behavior in the new Zr-2Mn alloy. The oxidation of alloy was performed at temperatures between 350°C and 900°C for 30 minutes. The hydrogen charging was made for 72 h at a current density 80 mA/cm2. The charged samples were heat treated at 400°C for 4 h to obtain a uniform hydrogen profile content across the sample. The oxidation resulted in an...
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 17. synthesis, extractive and ionophoric properties of p-tert-butylcalix[4]arene appended with hydroxamix acid moieties
PublikacjaThe synthesis and characterization of four p-tert-butylcalix[4]arene-hydroxamic acidc are reported. The dependence of the metal ion binding, assessed by liquid extraction of the metal nitrates from water into dichloromethane in individual and competitive experiments, on the ligand structure, is presented. The results showed that those ligands could be successfully used in separation process of trnasition and heavy metals often...
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MATERIAŁY I ELEMENTY STOSOWANE DO WYKONANIA LEKKIEJ OBUDOWY cz. 1. Materiały metalowe
PublikacjaW 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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Removal and speciation of heavy metals in the constructed wetland treating landfill leachate
PublikacjaThe results of heavy metals removal and speciation of metals at two treatment wetlands receiving landfill are discussed. The first TW is a surface flow facility consisting of 10 ponds. The next TW is a newly constructed pilot-scale facility consisting of three beds with alternately vertical and horizontal sub-surface flow. The metals concentrations were analysed in leachate(both TWs) and bottom sediments (surface flow TW). Seasonal...
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Effect of Bi2O3 Excess on Morphology and Structure of BiNbO4 Ceramics
PublikacjaGoal of the present research was to fabricate BiNbO4 ceramics from the mixture of powders by the solid state reaction route and pressureless sintering at various temperatures (TS =8700C and TS =9100C) and study microstructure, phase composition and crystalline structure of BiNbO4 ceramics. Four batches were fabricated and examined, namely the one fabricated from the stoichiometric mixture of reagent – grade oxide powders, viz....
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Mechanical and Microstructural Characterization of TIG Welded Dissimilar Joints between 304L Austenitic Stainless Steel and Incoloy 800HT Nickel Alloy
PublikacjaIn this article, the mechanical properties and microstructure of 304L austenitic stainless steel/Incoloy 800HT nickel alloy dissimilar welded joints are investigated. The joints were made of 21.3 mm × 7.47 mm tubes using the TIG process with the use of S Ni 6082 nickel filler metal. No welding imperfections were found and high strength properties of joints were obtained, meeting the assumed acceptance criteria of the product’s...
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Catalytic Asymmetric Synthesis of Isochroman Derivatives
PublikacjaThe isochroman scaffold constitutes an important structural unit, which is present in various bioactive natural products and synthetic pharmaceutical compounds exhibiting wide arrays of biological properties. Hence the synthesis of this class of heterocyclic compounds in a stereoselective fashion is highly significant and desirable. In the last decade, a substantial advancement has been witnessed ln the catalytic asymmetric...
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Structural and Transportation Properties of Strontium Titanate Composites with Ion Conductive Oxides
PublikacjaThis paper has been written based on the author’s doctoral dissertation “Structural and transportation properties of strontium and titanate composites with ion conductive oxides”, prepared under the supervision of Prof. Dr. Hab. Eng. Bogusław Kusz at the Department of Solid State Physics of Gdańsk University of Technology. It reports the idea of the thesis and conclusions from the study. Niobium doped strontium titanate (Sr(Ti,Nb)O3)...
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Nanolayers in Fiber-Optic Biosensing
PublikacjaIn this chapter, fiber-optic sensors based on nanolayers or thin films and their ability to perform biophotonic measurements is presented. In the last decade, fiber-optic sensors have gained popularity as biosensing devices. This has been made possible because of the design and the integration of new materials in fiber-optic technology. Nanolayers and thin films made from various materials such as nanodiamond (NCD), boron-doped...
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Study of the NO2 sensing mechanism of PEDOT-RGO film using in situ Raman Spectroscopy
PublikacjaIn this work, the mechanism of the NO2 reaction with PEDOT-RGO composite film has been investigated via in situ Raman spectroscopy. Reduced graphene oxide (RGO), poly(3,4-ethylenedioxytiophene)-reduced graphene oxide (PEDOT-RGO) and poly(3,4-ethylenedioxytiophene)/ClO4− (PEDOT/ClO4−) films were fabricated using an electrodeposition method and used as resistance sensors of gaseous nitrogen dioxide. The experimental results indicate...
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On the Possibility of the Amphotericin B-Sterol Complex Formation in Cholesterol- and Ergosterol-Containing Lipid Bilayers: A Molecular Dynamics Study
PublikacjaAmphotericin B (AmB) is a well-known membrane-active antibiotic that has been used to treat systemicfungal infections for more than 45 years. Therapeutic application of AmB is based on the fact that it is moreactive against ergosterol-containing membranes of fungal cells than against mammalian membranes withcholesterol. In this paper, we examine the hypothesis according to which the selectivity of the AmB's membraneaction originates...
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Experimental and Theoretical Screening for Green Solvents Improving Sulfamethizole Solubility
PublikacjaSolubility enhancement of poorly soluble active pharmaceutical ingredients is of crucial importance for drug development and processing. Extensive experimental screening is limited due to the vast number of potential solvent combinations. Hence, theoretical models can offer valuable hints for guiding experiments aimed at providing solubility data. In this paper, we explore the possibility of applying quantum-chemistry-derived...
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Elctrochemical oxidation and corrosion resistance of the Ti13Nb13Zr alloy
PublikacjaThis paper presents the results of oxidation and corrosion tests carried out on titanium alloy Ti13Nb13Zr. The oxide film was prepared by electrochemical environment 2M H3PO4 for 30 min and 1 h, at a constant voltage 40V. The tests of corrosion resistance were performed by potentiostatic method in Ringer's solution at different pH values: 7, 5 and 3. The change in an appearance of surface and the increase in corrosion resistance...
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The mechanisms of degradation of titanium dental implants
PublikacjaTitanium dental implants show very good properties, unfortunately there are still issues regarding material wear due to corrosion, implant loosening, as well as biological factors—allergic reactions and inflammation leading to rejection of the implanted material. In order to avoid performing reimplantation operations, changes in the chemical composition and/or modifications of the surface layer of the materials are used. This research...
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Cation sensing by diphenyl-azobenzocrowns
PublikacjaMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
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Determination of metals in water samples by atomic absorption spectrometry and flame emission spectrometry
PublikacjaMetal species in environmental waters are relevant to characterize the metal toxicity, the mobility between different environmental compartments, and for remediation purposes in case of contamination. The concentration of many trace metals in natural water samples are generally at µg/l level. The paper describes determination of metals in water samples based on flame atomic emission and flame atomic absorption spectrometry.
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Formation of High Corrosion Resistant Nanotubular Layers on TitaniumAlloy Ti13Nb13Zr
PublikacjaThis paper presents results of oxidation tests and corrosion investigations of titanium alloy Ti13Nb13Zr performed at different conditions. The oxide layers have been formed by electrochemical method in 2M H3PO4 + 0.3% HF solution for 30 min. and 1 h at 20 V constantvoltage. The corrosion tests have been made by potentiodynamic method in Ringer`s solution at pH ranged between 3 and 7. It has been shown that the nano-oxide films,...
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Formation of High Corrosion Resistant Nanotubular Layers on TitaniumAlloy Ti13Nb13Zr
PublikacjaThis paper presents results of oxidation tests and corrosion investigations of titanium alloy Ti13Nb13Zr performed at different conditions. The oxide layers have been formed by electrochemical method in 2M H3PO4 + 0.3% HF solution for 30 min. and 1 h at 20 V constantvoltage. The corrosion tests have been made by potentiodynamic method in Ringer`s solution at pH ranged between 3 and 7. It has been shown that the nano-oxide films,...
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Unveiling the Pool of Metallophores in Native Environments and Correlation with Their Potential Producers
PublikacjaFor many organisms, metallophores are essential biogenic ligands that ensure metal scavenging and acquisition from their environment. Their identification is challenging in highly organic matter rich environments like peatlands due to low solubilization and metal scarcity and high matrix complexity. In contrast to common approaches based on sample modification by spiking of metal isotope tags, we have developed a two-dimensional...
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UKŁADY KONSTRUKCYJNE LEKKIEJ OBUDOWY
PublikacjaW artykule przedstawiono rozwiązania konstrukcyjne przegród zewnętrznych lekkiej obudowy jednowarstwowych (nieizolowanych termicznie), wielowarstwowych (izolowanych termicznie) oraz szklano-metalowych. Omówiono procesy modyfikacji konstrukcji ścian. Podano przykładowe rozwiązania.
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Modeling N2O behavior during denitrification with different carbon sources and electron acceptors
PublikacjaA mathematical model was developed for identification of the most important mechanism leading to nitrous oxide (N2O) accumulation in denitrifying activated sludge systems. The activated sludge model No. 2d (ASM2d) was extended to include intermediate three steps of the denitrification process. The formation and accumulation of nitric oxide (NO) was assumed to be very low in the performed laboratory experiments. These experiments...
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Diffusible hydrogen management in underwater wet self-shielded flux cored arc welding
PublikacjaThis article reports the effect of underwater wet welding parameters and conditions on the diffusible hydrogen content in deposited metal for welding with a self-shielded flux cored wire. The diffusible hydrogen content in deposited metal was determined using the glycerin method according to the Plackett-Burman design determining the significance of the effect of the stick out length, welding current, arc voltage, travel speed...
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Determination of moisture resistance of covered electrodes according to PN-EN ISO 14372
PublikacjaMoisture present in the electrode covering is one of the sources of diffusible hydrogen in welded joints. In order to study the diffusible hydrogen content in deposited metal, a stand for moisturizing covered electrodes, in accordance with the PN-EN ISO 14372 standard, was built. After the stand was completed, a test of moisturizing the electrodes was carried out and measurements of the diffusible hydrogen content in deposited...
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Modified Manganese Phosphate Conversion Coating on Low-Carbon Steel
PublikacjaConversion coatings are one of the primary types of galvanic coatings used to protect steel structures against corrosion. They are created through chemical reactions between the metal surface and the environment of the phosphating. This paper investigates the impact that the addition of new metal cations to the phosphating reaction environment has on the quality of the final coating. So far, standard phosphate coatings have contained...
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Study on Microstructure-Property Relationship of Inconel 617 Alloy/304L SS Steel Dissimilar Welds Joint
PublikacjaWelding of Inconel 617 (IN617) alloy and austenitic 304L SS steel has been attempted using the autogenous Laser Beam Welding (LBW) process. Characterization of dissimilar weldments was performed on either side of the fusion boundaries. The metallographic results showed that the inhomogeneous microstructure formation for weld metal contained columnar and cellular dendrites near the interface, whilst the columnar, cellular and equiaxed...
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Analysis of guided wave propagation in adhesive joints of steel rods
PublikacjaThe aim of the study is the elastic wave propagation in adhesive joints of metal rods that are one of the simplest kind of glue connections. They are consisted of two metal members and an adhesive layer joining two parts together. The analysis is directed to technical diagnostics of such type of connections. Longitudinal and transversal guided waves were excited in prepared joints. Signals of propagating waves were registered in...
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ELECTRON-IMPACT IONIZATION CROSS SECTIONS CALCULATIONS FOR PURINE AND PYRIMIDINE MOLECULES
PublikacjaCross sections for electron-impact ionization of purine and pyrimidine molecules have been calculated using binary-encounter-Bethe method for electron energies ranging from the ionization threshold up to 5 keV. Ionization cross section for purine molecules is 1.4 times higher than for pyrimidine molecules. Acceptable agreement between experimental and theoretical ionization data for pyrimidine molecule has been found.
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Phase Transition in a Sequence-Structure Channel
PublikacjaWe study an interesting channel which maps binary sequences to self-avoiding walks in the two-dimensional grid, inspired by a model of protein folding from statistical physics. The channel is characterized by a Boltzmann/Gibbs distribution with a free parameter corresponding to temperature. We estimate the conditional entropy between the input sequence and the output fold, giving an upper bound which exhibits an unusual phase transition...
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Fabrication and photoactivity of organic-inorganic systems based on titania nanotubes and PEDOT containing redox centres formed by different Prussian Blue analogues
PublikacjaHerein, the heterojunction composed of an inorganic substrate: ordered hydrogenated titania nanotubes (H-TiO2NTs) and a deposited organic film: poly(3,4-ethylenedioxythiophene) (PEDOT) is reported. The conducting polymer is modified with different transition metal haxacyanoferrates (Mehcf), wherein as metal: copper, iron, cobalt and nickel are introduced. The presence of various metal centres provides characteristic redox activity...
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Multi-Analytical Techniques for the Study of Burial Clothes of Polish King Sigismund III Vasa (1566–1633) and His Wife Constance Habsburg (1588–1631)
PublikacjaThe subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance...
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The hydration of selected biologically relevant molecules – the temperature effect on apparent molar volume and compression
PublikacjaThe densities and sound velocities at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K were measured for aqueous solutions of glycine, trimethylamine-N-oxide, taurine and N-methylacetamide. From these data, the apparent molar volumes, V the apparent molar isentropic compressions, KS,, and the Passynski hydration numbers of solutes were determined. The concentration dependencies of the calculated quantities, their limiting values...
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Stanowisko do analizy sygnałów przesyłanych w kanale hydroakustycznym
PublikacjaOpisano stanowisko badawcze, za pomocą którego wyznaczano odpowiedzi kanału hydroakustycznego na pobudzenie sygnałem modulowanym ciągiem pseudoprzypadkowym PRBS (Pseudo Random Binary Sequence) oraz przeprowadzono eksperymenty z transmisją danych z rozpraszaniem widma metodą bezpośrednią. Omówiono wyniki badań w warunkach laboratoryjnych oraz w jeziorze i basenie portu morskiego. Badania wykonano w warunkach statycznych.
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Pipeline geometry defects in high resolution pig's data
PublikacjaMost of the pipelines have been inspected at least once using intelligent pigging. The problem of specific software for interactive presentation, analysis and comparison of features revealed during the consecutive geometry surveys is emphasized. Capabilities of a simultaneous measurement of internal geometry and metal loss features in a single run are illustrated. Advantages of application of statistical characteristics of both...
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Preparation, characterization and photocatalytic activity of TiO2 microspheres decorated by bimetallic nanoparticles
PublikacjaComposite photocatalysts that consist of TiO2and noble metal nanostructures have been considered tobe the promising and pivotal material for accessible enhancement of the efficiency in the photocatalyticprocess carried out in the aqueous and gas phases. In this work we fabricated porous TiO2microspheresthrough a hydrothermal process followed by photochemical reduction of noble metal nanoparticles atthe TiO2surface. The morphology...
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Influence of dopants on structure of polycrystalline bismuth niobate
PublikacjaBismuth niobate (BiNbO4) has attracted attention as a low-fired ceramics with promising microwave application potential. BiNbO4 ceramics was fabricated by mixed oxide method and sintered at temperature T<1000˚C. As the sintering aids a small amount of CuO oxide was used. The crystalline structure of the ceramic samples was examined by X-ray diffraction method at room temperature. The Rietveld refinement method was used for analysis...
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Oxidation kinetics of Zircaloy-4 alloy at 673 K determined by GDOES technique
PublikacjaOxidation of zirconium alloys is a process that takes place during the operation of nuclear reactors and is essential for assessing the durability of fuel claddings. The present study was aimed to determine the oxidation kinetics of the Zircaloy-4 alloy using GDOES (glow discharge optical emission spectroscopy) at temperature 673 K corresponding to the conditions of use of fuel pellets. The tests were performed on non-oxidized...
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Distinguishing of cocrystals from simple eutectic mixtures: phenolic acids as potential pharmaceutical coformers
PublikacjaThe multiparameter model comprising 1D and 2D QSPR/QSAR descriptors was proposed and validated for phenolic acid binary systems. This approach is based on the optimization of regression coefficients for maximization of the percentage of true positives in the pool of systems comprising either simple binary eutectics or cocrystals. The training set consisted of 58 eutectics and 168 cocrystals. The solid dispersions collection used...
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Bonding in Phosphanylphosphinidene Complexes of Transition Metals and their Correlation with Structures, 31 P NMR Spectra, and Reactivities
PublikacjaTheoretical studies of the bonding interactions and most important properties are carried out for isolable phosphanylphosphinidene complexes of transition metals. Three main types of phosphanylphosphinidene complexes are distinguished, based on the way in which the phosphanylphosphinidene ligand bonds to the metal center: (i) side-on complexes of platinum, where the R2Pβ–Pα ligand mimics structural features of free singlet phosphanylphosphinidenes...
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The comparison of SrTi0.98Nb0.02O3–δ-CeO2 and SrTi0.98Nb0.02O3–δ-YSZ composites for use in SOFC anodes
PublikacjaComposites of Nb-doped strontium titanate mixed with yttria-stabilized zirconia or cerium oxide in 50:50, 70:30 and 85:15 weight ratios were evaluated as possible anode/electrolyte interface materials for solid oxide fuel cells in terms of chemical compatibility, electrical conductivity and mechanical properties. It has been shown that composite samples prepared by typical powder-mixing methods remain single-phase up to 1400°C....
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Hydroxyapatite coatings on porous ti and ti alloys
PublikacjaDeposition of hydroxyapatite coating on porous Ti and Ti alloys with electrochemical and biomimetic deposition approach is presented. The enhancement of phosphates deposition by well oriented and uniform titanium oxide nanotube array on the surface of titanium substrate is discussed.
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A first-principles study of electronic and magnetic properties of 4d transition metals doped in Wurtzite GaN for spintronics applications
PublikacjaWe studied the electronic and magnetic properties of wurtzite GaN (w-GaN) doped with different concentrations of the 4d transition metal ions Nb, Mo, and Ru. We incorporated spin-polarized plane-wave density functional theory within an ultrasoft pseudopotential formalism. The 4d transition metals were doped at different geometrical sites to determine the geometry with the lowest total energy and the one that induced the largest...
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Laser Dissimilar Welding of AISI 430F and AISI 304 Stainless Steels
PublikacjaA dissimilar autogenous laser welded joint of AISI 430F (X12CrMoS17) martensitic stainless steel and AISI 304 (X5CrNi18-10) austenitic stainless steel was manufactured. The welded joint was examined by non-destructive visual testing and destructive testing by macro- and microscopic examination and hardness measurements. With reference to the ISO 13919-1 standard the welded joint was characterized by C level, due to the gas pores...
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Induction of chirality in 4,4'-azopyridine by halogen-bonding interaction with optically active ditopic donors
PublikacjaOptically active ditopic halogen bond donors bearing two 4-iodotetrafluorophenyl groups were obtained by reaction of chiral diols with iodopentafluorobenzene. Co-crystallization of these donors with anti-4,4′-azopyridine afforded binary complexes containing infinite chains of the alternating component molecules connected by halogen bonds. The solid state CD measurements confirmed that complexation induces optical activity of the...
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Analyzing sets of phylogenetic trees obtained from bayesian MCMC process using topology metrics
PublikacjaThe reconstruction of evolutionary trees is one of the primary objectives in phylogenetics. Such a tree represents historical evolutionary relationship between different species or organisms. Tree comparisons are used for multiple purposes, from unveiling the history of species to deciphering evolutionary associations amongorganisms and geographical areas.In the paper, we describe a general method for comparing hylogenetic trees....
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Ecotoxicological equilibria of triclosan inMicrotox, XenoScreen YES/YAS, Caco2, HEPG2 and liposomal systems are affected by the occurrence of other pharmaceutical and personal care emerging contaminants
PublikacjaContaminants of emerging concernmay be considered as any chemicals or factorswhose unintended continuous release and persistence in the environmentmay lead to any observable undesirable response of living beings. Still not much is known on reciprocal toxicological impact of given chemicals when present in binary or more complex mixtures. In thiswork, an attemptwas thus undertaken to study the impact of butylparaben,methylparaben and...
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Corrosion Study of Ceria Protective Layer Deposited by Spray Pyrolysis on Steel Interconnects
PublikacjaSingle fuel cells and electrolysis cells are assembled into stacks using interconnects in order to increase power and gas production capacity. The most common choice for the interconnect material is stainless steel. It has good electrical and mechanical properties and is also cost effective. One of the problems when using steel is the formation of a thermally grown oxide scale during use which has a lower electrical conductivity...
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Catalytic Mechanism of Non-Target DNA Cleavage in CRISPR-Cas9 Revealed by Ab Initio Molecular Dynamics
PublikacjaCRISPR-Cas9 is a cutting-edge genome editing technology, which uses the endonuclease Cas9 to introduce mutations at desired sites of the genome. This revolutionary tool is promising to treat a myriad of human genetic diseases. Nevertheless, the molecular basis of DNA cleavage, which is a fundamental step for genome editing, has not been established. Here, quantum–classical molecular dynamics (MD) and free energy methods are used...
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Metallurgical characterization and high-temperature tensile failure of Inconel 617 alloy welded by GTAW and SMAW—a comparative study
PublikacjaTwo types of the weld joint of Inconel 617 alloy were produced using gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) processes with ERNiCrCoMo-1 filler metal and ENiCrCoMo-1 electrode, respectively. The weld metal showed the segregation of the principle alloying elements like Mo and Cr along the inter-dendritic spaces, triggering the formation of secondary phases. The microstructure characterization of the...
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Nanokrystaliczne warstwy ceramiczne otrzymywane metodą pirolizy aerozolowej w tlenkowych ogniwach paliwowych
PublikacjaNiniejsza rozprawa doktorska dotyczy badań materiałów wytwarzanych w postaci cienkich, nanokrystalicznych warstw ceramicznych metodą pirolizy aerozolowej dla zastosowań w tlenkowych ogniwach paliwowych (SOFC). Badane są trzy możliwe obszary zastosowań wytwarzanych warstw tj. osadzanie powłok ochronnych na stalowych interkonektorach dostarczających gazy do elektrody tlenowej, wytwarzanie bariery ochronnej zapobiegającej dyfuzji...
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Assessment of fitness for service of Cr-Mo steel tubes in catalytic reforming charge heaters
PublikacjaIn this paper characteristic features of metal dusting corrosion in high temperature gas mixtures of high carbon activity in catalytic reforming units, including Continuous Catalyst Regeneration (CCR) platformer are presented. Examples of 2.25Cr-1Mo and 9Cr-1Mo steel tubes at advanced stages of metal dusting process after long-term service in charge heaters are used to prove that destructive examinations are necessary to provide...