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Investigation of the C-1311 glucuronidation: an electrochemical approach
Dane BadawczeThis study was undertaken to investigate the glucuronidation of the compound C-1311 (5-diethylaminoethylamino-8-hydroxyimidazoacridinone – the model anticancer acridine derivative) using electrochemistry/mass spectrometry (EC/MS) as a complementary technique to in vitro (liver microsomes) and in silico approaches.
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Micellar Route of the Synthesis of Alkyl Xylosides: An Unexpected Effect of Amphiphilic Imidazolium Ionic Liquids
PublikacjaThis manuscript presents results from the investigation on the synthesis of alkyl xylosides by the novel, very efficient and promising protocol of the Fischer synthesis from unprotected xylose and aliphatic alcohol. The use of 1-alkyl-3-methylimidazolium hydrogen sulfate ionic liquids as the catalysts with dual functionality (surfactant + acid catalyst) and micellar reaction system are the main novelty of described method. It has...
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Characterization of magnesium doped lanthanum orthoniobate synthesized by molten salt route
PublikacjaMolten salt synthesis method has been used to prepare the single phase magnesium doped lanthanum orthoniobate. The phase composition has been checked by X-ray diffraction method and the microstructure studies have been performed by scanning electron microscopy. The high temperature properties of the material have been investigated by thermogravimetry and electrochemical impedance spectroscopy. A dependence between sample total...
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Characterization of structural, thermal and mechanical properties of bismuth silicate glasses
Publikacjahe influence of heating and reduction processes on the structural, thermal and mechanical properties of bismuth-silicate glasses has been investigated. Two compositions of glasses: 40Bi2O3–60SiO2 (Bi0.57Si0.43Ox) and 27Bi2O3–73SiO2 (Bi0.43Si0.57Ox) were fabricated by a typical melt quenching technique. Then the reduction in hydrogen at 380 °C for 20, 42 or 67 h was performed. It was found that a 50 μm-thick layer was formed on...
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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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Tuning Ferulic Acid Solubility in Choline-Chloride- and Betaine-Based Deep Eutectic Solvents: Experimental Determination and Machine Learning Modeling
PublikacjaDeep eutectic solvents (DES) represent a promising class of green solvents, offering particular utility in the extraction and development of new formulations of natural compounds such as ferulic acid (FA). The experimental phase of the study undertook a systematic investigation of the solubility of FA in DES, comprising choline chloride or betaine as hydrogen bond acceptors and six different polyols as hydrogen bond donors....
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Shooting Gas Cylinders to Prevent Their Explosion in Fire
PublikacjaGas cylinders in general, and particularly cylinders containing acetylene, constitute a great potential danger to fire and rescue services involved in salvage operations. Experiments show that gas cylinders with acetylene, oxygen, hydrogen, CNG, LPG or CO2 may blow after short exposition to heat with very destructive effect as fragments of blown cylinder may fly even several hundred meters. In the case of acetylene the explosion...
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Synthesis and properties of porous Sr 0.96 Y 0.04 Ti 1−x Nb x O 3
PublikacjaA 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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ortho-Fluorobenzanilides and ortho-fluorothiobenzanilides: Molecular conformations and crystal packing
PublikacjaSeries of 2-fluoro and 2,6-difluorobenzanilides and their thiobenzanilide analogs have been synthesized to investigate the influence of the fluorine atom on their crystal structures and self-assembly in the crystal lattice. The X-ray analysis of the single crystal revealed that the synthesized molecules adopt a geometry being deflected from planarity. The deflection was investigated by analysis of dihedral angles between mean planes...
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Novel method for metal-oxide glass composite fabrication for use in thermoelectric devices
PublikacjaA novel method for thermoelectric materials fabrication using a reduction of oxide precursors in hydrogen was reported. On the example of Bi-Sb, Bi-Sb-Te and Te-Ag-Ge-Sb compounds it was shown that this simple and easy method is suitable for fabrication of two-, three- and even multicomponent thermoelectric materials. It allows controlling a composition, microstructure and even type a of electrical charge carriers. As a result...
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Charge-based deep level transient spectroscopy of B-doped and undoped polycrystalline diamond films
PublikacjaThe undoped and B-doped polycrystalline diamond thin film was synthesized by hot filament chemical vapor deposition and microwave plasma, respectively. The structural characterization was performed by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The electrical properties of synthesized diamond layer were characterized by dc-conductivity method and charge deep level transient spectroscopy. The B-doped...
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Pyrolysis of RDF and Catalytic Decomposition of the Produced Tar in a Char Bed Secondary Reactor as an Efficient Source of Syngas
PublikacjaOne of the technical limitations of refuse-derived fuel (RDF) pyrolysis is the high content of tar in its gas products. In order to resolve this problem, a two-stage RDF pyrolysis with a catalyst based on char from RDF pyrolysis is proposed. This paper presents the results of municipal waste pyrolysis beginning in an oven heated to 480 °C and ending with catalytic tar cracking carried out in the temperature range from 800 to 1000...
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Exfoliated graphite with spinel oxide as an effective hybrid electrocatalyst for water splitting
PublikacjaThe aim of the conducted research was to develop hybrid nanostructures formed from MnCo2O4 and exfoliated graphite. Carbon added during the synthesis allowed for obtaining a well-distributed MnCo2O4 particle size with exposed active sites contributing to the increased electric conductivity. The influence of the weight ratios of carbon to a catalyst for hydrogen and oxygen evolution reactions was investigated. The new bifunctional...
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Wymagania inżynierii systemów dla maszyn wirujących (PG-00060237)
Kursy OnlineTurbiny wiatrowe, gazowe, mikroturbiny, silniki lotnicze, turbosprężarki i inne systemy mechaniczne to przykłady maszyn wirujących, które wymagają wysoko wykwalifikowanych inżynierów. Powinni oni zrozumieć złożoność procesów projektowania i produkcji, w tym wytwarzania przyrostowego, oraz konserwacji prognostycznej opartej na inżynierii cyfrowej dla bezawaryjnej pracy silnika. Kurs zapewnia fundamentalną wiedzę wymaganą w przemyśle...
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Gasification of Densified Biomass (DB) and Municipal Solid Wastes (MSW) Using HTA/SG Technology
PublikacjaThe necessity of economical and rational use of natural energy sources caused a rapid development of research on the possibilities of using non‐conventional energy resources. Taking the above into account, a new technological process of thermochemical conversion of biomass and communal waste, commonly known as High Temperature Air/Steam Gasification (HTA/SG) and Multi‐Staged Enthalpy Extraction Technology (HTAG‐MEET), was developed....
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublikacjaIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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Bis(ammonium) Zoledronate Dihydrate
PublikacjaNeutralization of 2-(1-imidazole)-1-hydroxyl-1,1`-ethylidenediphosphonic acid (zoledronic acid) by an excess of ammonia yielded bis(ammonium) zoledronate dihydrate, {C5H8N2O7P2 2−, 2(H4N+), 2(H2O)}. The product is readily soluble in water and forms monocrystals for which the X-ray structural analysis was carried out. The zoledronic anion is of double negative charge due to deprotonation of three P–OH groups and protonation of the...
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Investigation of H2:CH4 plasma composition by means of spatially resolved optical spectroscopy
PublikacjaThe system based on spatially resolved optical emission spectroscopy dedicated for in situ diagnostics of plasma assisted CVD processes is presented in this paper. Measurement system coupled with chemical vapour deposition chamber by dedicated fiber-optic paths enables investigation of spatial distribution of species densities (Hx, H+, CH, CH+) during chemical vapour deposition process. Experiments were performed for a various...
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The effect of ionic liquids on the surface and photocatalytic properties of semiconducting materials
PublikacjaSemiconductor-mediated photocatalysis represents an environmentally friendly technology that could be used for the degradation of different pollutants in the gas and aqueous phases, for hydrogen generation, and for CO2-to-valuable product transformation reactions. Therefore, it is extremely important to accurately design a photocatalyst with the relevant features. In recent years, ionic liquids have often been employed as reagents...
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Superexcited states in the vacuum-ultraviolet photofragmentation of isoxazole molecules
PublikacjaThe photofragmentation of isoxazole molecules producing excited atomic and molecular fragments has been investigated over the energy range 16-50 eV, using photon-induced fluorescence spectroscopy. The following fragments have been identified by their fluorescence: the excited hydrogen atoms H(n), n = 3-7 and the diatomic CH(A2Δ, B2Σ−), CN(B2Σ+) and C2(d3Πg) fragments. The diatomic fragments are vibrationally and highly rotationally...
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Chromogenic amides of pyridine-2,6-dicarboxylic acid as anion receptors
PublikacjaThe synthesis of simple, chromogenic pyridine-2,6-dicarboxylic acid amides, derivates of isomeric nitroanilines and aminonitrophenols, and their ion binding properties are described. The ligands' response to ionic species was examined by naked eye and was studied with the use of UV-Vis spectroscopy in DMSO and its mixture with water. The effect of the localisation and the type of the substituents in aromatic rings were discussed....
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<i>N,N,N</i>-Trimethyl-N-(methyl 5-deoxy-2,3-<i>O</i>-isopropylidene-β-D-ribofuranosid-5- yl)ammonium 4-methylbenzenesulfonate sesquihydrate.
PublikacjaThe structure of the title compound, [C12H24NO4][C7H7O3S]·1.5H2O, contains alternating layers parallel to (001) of hydrophobic and polar character, stabilized by C-H...O hydrogen bonding. The furan ring adopts an envelope conformation with the C(OMe) atom as the flap, and the dioxolane ring is twisted about one of the O-C(methine) bonds. A comparison to related compounds is presented. The tosylate-O atoms were disordered over two...
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Fabrication, Microstructure and High Temperature Corrosion Resistance of Porous Alloys for Solid Oxide Fuel Cells
PublikacjaPorous alloys find use in modern Solid Oxide Fuel Cells as the supporting structures. As they are exposed to high temperatures (> 500°C) an oxide scale forms on their surface due to high temperature corrosion phenomena. Since the ratio between the surface area and volume is much higher than for planar samples, formation of the oxide can lead to a breakaway oxidation after relatively short times. Therefore corrosion properties of...
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Features extraction from the electrocatalytic gas sensor responses
PublikacjaOne of the types of gas sensors used for detection and identification of toxic-air pollutant is an electrocatalytic gas sensor. The electrocatalytic sensors are working in cyclic voltammetry mode, enable detection of various gases. Their response are in the form of I-V curves which contain information about the type and the concentration of measured volatile compound. However,...
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Structure and thermoelectric properties of Bi–Te alloys obtained by novel method of oxide substrates reduction
PublikacjaA novel method of thermoelectric materials fabrication has been developed. Oxide reagents have been melted at high temperature in air, quenched, milled to powder and reduced in hydrogen to form Bi–Te alloys. Structural and thermoelectric properties of samples have been investigated depending on initial composition and temperature of reduction process. Sample 25Bi2O3–75TeO2 reduced at 340 °C for 10 h has been found to be a p-type...
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Time evolution of Electrochemical Impedance spectra of cathodically protected steel in artificial seawater
PublikacjaUsability of Electrochemical Impedance Spectroscopy data for better cathodic protection control was investigated. Carbon steel – S235JR2 grade specimen were exposed in artificial seawater environment. Samples were polarized and their potentials corresponded to four different cathodic protection degrees. Time evolution of Electrochemical Impedance spectra was investigated. Goodness of fit function (X2) was analysed in terms of proper...
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Carboxylation Enhances Fragmentation of Furan upon Resonant Electron Attachment
PublikacjaWe report a dissociative electron attachment study to 2-furoic acid (C5H4O3) isolated in a gas phase, which is a model molecule consisting of a carboxylic group and a furan ring. Dissociation of furan by low energy electrons is accessible only via electronic excited Feshbach resonances at energies of incident electrons above 5 eV. On the other hand, carboxylic acids are well- known to dissociate via attachment of electrons at subexcitation energies....
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Thermochemical Conversion of Biomass and Municipal Waste into Useful Energy Using Advanced HiTAG/HiTSG Technology
PublikacjaAn advanced thermal conversion system involving high-temperature gasification of biomass and municipal waste into biofuel, syngas or hydrogen-rich gas is presented in this paper. The decomposition of solid biomass and wastes by gasification is carried out experimentally with a modern and innovative regenerator and updraft continuous gasifier, among others. A ceramic high-cycle regenerator provides extra energy for the thermal conversion...
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Green adsorbents and solvents in food analysis
PublikacjaGreen analytical chemistry aims to minimize the negative impact of analytical procedures on the environment and human health. This can be achieved through the use of non-toxic and environmentally friendly reagents. Classical green solvents include water, ethanol, acetone, and supercritical fluids. Water has been used for the extraction of water-soluble compounds (sugars, amino acids). Ethanol and acetone have been used for the...
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Deep eutectic solvent-based shaking-assisted extraction for determination of bioactive compounds from Norway spruce roots
PublikacjaPolyphenolic compounds play an essential role in plant growth, reproduction, and defense mechanisms against pathogens and environmental stresses. Extracting these compounds is the initial step in assessing phytochemical changes, where the choice of extraction method significantly influences the extracted analytes. However, due to environmental factors, analyzing numerous samples is necessary for statistically significant results,...
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Interactions of fish gelatin and chitosan in uncrosslinked and crosslinked with EDC films: FT-IR study
PublikacjaFilms based on fish gelatin, chitosan and blend of fish gelatin and chitosan before and after cross-linking with EDC have been characterized by FT-IR spectroscopy. The FT-IR spectrum of fish gelatin film showed the characteristic amide I, amide II and amide III bands, and the FT-IR spectrum of chitosan film confirmed that the polymer was only a partially deacetylated product, and included CH3-C=O and NH2 groups, the latter both...
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The influence of the welding environment on the properties of Tekken joints made from S355J2C+N steel
PublikacjaThere are three main methods of underwater welding: dry, wet and intermediate between them, by using the local dry chamber. Due to low costs, the most common method is the wet welding with the use of covered electrodes. Water as a welding environment carries out a lot of problems. The first is limited visibility and instability of the welding arc. The biggest problem during underwater welding is high susceptibility to cold cracking,...
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Furan Fragmentation in the Gas Phase: New Insights from Statistical and Molecular Dynamics Calculations
PublikacjaWe present a complete exploration of the different fragmentation mechanisms of furan (C4H4O) operating at low and high energies. Three different theoretical approaches are combined to determine the structure of all possible reaction intermediates, many of them not described in previous studies, and a large number of pathways involving three types of fundamental elementary mechanisms: isomerization, fragmentation, and H/H2 loss...
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Rozdział 10.2 Metody oznaczania właściwości przeciwutleniających próbek żywności
PublikacjaWystępowanie większości chorób cywilizacyjnych może być rezultatem stresu oksydacyjnego prowadzącego do różnorodnych zmian w ludzkim organizmie, wywołanych działaniem tzw. reaktywnych form tlenu. Z tego też powodu pojawiło się olbrzymie zapotrzebowanie na szybkie testy umożliwiające pomiar całkowitej zawartości przeciwutleniaczy czy też ogólnej siły przeciwutleniającej produktów żywnościowych a w szczególności świeżych warzyw...
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Dissociation and fragmentation of furan by electron impact
PublikacjaDissociation and fragmentation processes that produce electronically excited atomic and molecular fragments, following electron impact excitation, have been studied in furan. The optical excitation technique has been employed over the electron incident energy range 15-95 eV. Formation of excited hydrogen atoms H(n) in the n = 4-10 states has been detected by observation of the Balmer series. The diatomic CH fragments are formed...
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Ultrafast Intramolecular Relaxation and Wave-Packet Motion in a Ruthenium-Based Supramolecular Photocatalyst
PublikacjaThe hydrogen-evolving photocatalyst [(tbbpy)2 Ru(tpphz)Pd(Cl)2 ](2+) (tbbpy=4,4'-di-tert-butyl-2,2'-bipyridine, tpphz=tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]phenazine) shows excitation-wavelength-dependent catalytic activity, which has been correlated to the localization of the initial excitation within the coordination sphere. In this contribution the excitation-wavelength dependence of the early excited-state relaxation...
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Risks related to car fire on innovative Poroelastic Road Surfaces-PERS
PublikacjaTo reduce tyre/road noise, the concept of poroelastic road surfaces (PERS) was invented. PERS is a road surface material that is porous, and at the same time, it is flexible because of the substantial amount of rubber granulate content (from 20% to 85%). The rubber and stone particles are bound by polyurethane resin instead of bitumen. It was feared that in case of fire, because of the high content of rubber and polyurethane, there...
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Spatial characterization of H 2: CH 4 dissociation level in microwave ECR plasma source by fibre-optic OES
PublikacjaSpatially resolved optical emission spectroscopy (SR-OES) was used to investigate microwave activated H2/Ar/CH4 plasma under conditions of the electron cyclotron resonance (ECR). The chemistry and composition of the gas phase were studied using self-designed fibre-optic system with echelle type spectrometer during CVD deposition of polycrystalline diamond. One-dimensional intensity profiles of the main species were collected along...
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Nowoczesne metody termochemicznej konwersji biomasy w paliwa gazowe, ciekłe i stałe = Modern methods of thermochemical biomass conversion into gas, liquid and solid fuels
PublikacjaBiomass utilization through direct- or co-combustion with coal, based on coal, hydrogen and oxygen compounds chemical energy conversion into heat in boilers, is simultaneously the cheapest and - according to experts - economically least effective solution. In case of heat and electricity production in cogeneration process in biomass fueled heat and power stations (wood, straw, energetic plants, RDF etc), investment costs are little...
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Application of Spinel and Hexagonal Ferrites in Heterogeneous Photocatalysis
PublikacjaSemiconducting materials display unique features that enable their use in a variety of applications, including self-cleaning surfaces, water purification systems, hydrogen generation, solar energy conversion, etc. However, one of the major issues is separation of the used materials from the process suspension. Therefore, chemical compounds with magnetic properties have been proposed as crucial components of photocatalytic composites,...
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Influence of alkaline and oxidative pre-treatment of waste corn cobs on biohydrogen generation efficiency via dark fermentation
PublikacjaStages of waste corn cobs processing leading to the production of biohydrogen via dark fermentation are presented and discussed in this paper. Firstly, the effects of pretreatment conditions i.e. alkaline, alkaline-oxidizing and Fenton oxidizing pre-treatment of lignocellulosic biomass on the removal of lignin were examined. The solid residue obtained in the first stage was subjected to saccharification by means of enzymatic hydrolysis....
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Structural changes of bacterial cellulose due to incubation in conditions simulating human plasma in the presence of selected pathogens
PublikacjaBacterial nanocellulose (BNC) is a natural biomaterial with a wide range of medical applications. However, it cannot be used as a biological implant of the circulatory system without checking whether it is biodegradable under human plasma conditions. This work aimed to investigate the BNC biodegradation by selected pathogens under conditions simulating human plasma. The BNC was incubated in simulated biological fluids with or...
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Cold plasma treatment of tannic acid as a green technology for the fabrication of advanced cross-linkers for bioactive collagen/gelatin hydrogels
PublikacjaTannic acid (TA) is a natural compound studied as the cross-linker for biopolymers due to its ability to form hydrogen bonds. There are different methods to improve its reactivity and effectiveness to be used as a modifier for biopolymeric materials. This work employed plasma to modify tannic acid TA, which was then used as a cross-linker for fabricating collagen/gelatin scaffolds. Plasma treatment did not cause any significant...
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Optimization of biocorrosion resistance and mechanical properties of PM Ti–XAl–2Fe–3Cu alloys by response surface methodology
PublikacjaIn the current study, the biocorrosion resistance and mechanical properties of the Ti–XAl–2Fe–3Cu (wt%) (X = 6, 4, 2 wt%) alloy produced by powder compact extrusion of blended elemental powders were optimized by using the response surface methodology in order to gain the best combination of processing parameters. To run the optimization process, central composite design with three equal levels of oxygen, hydrogen and aluminum was...
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Ultrafast degradation of brilliant cresyl blue under hydrodynamic cavitation based advanced oxidation processes (AOPs)
PublikacjaThe study highlights effectiveness of hydrodynamic cavitation (HC) in the degradation of effluents polluted by Brilliant Cresyl Blue (BCB) dye. Optimal process parameters were cavitation number 0.27, inlet pressure 1.70 bar, temperature 20 °C and pH 7. The efficiency of HC was investigated in combination with other advanced oxidation processes, including the addition of external oxidants (hydrogen peroxide, ozone, and sodium persulfate)...
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AlP compound and P-doping for promotion of electrocatalytic activity of N-doped carbon derived from metal-organic framework
PublikacjaWater splitting plays a key role in future fuels, where two processes occur - the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Nitrogen-doped carbon derived from...
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Spawalność ferrytyczno-austenitycznej stali odpornej na korozję typu dupleks 2205 w warunkach podwodnych
PublikacjaPraca dotyczy problemów spawalności stali odpornej na korozję typu dupleks w warunkach spawania mokrego elektrodami otulonymi i lokalną komorą suchą. Całość rozprawy składa się z dwóch części. Część pierwsza to przegląd literatury, w którym omówiono główne problemy wynikające z przeniesienia procesu spawania pod wodę oraz sposoby minimalizowania negatywnego wpływu środowiska. Część druga jest częścią doświadczalną, zawiera tezę...
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Determination of toxic gases based on the responses of a single electrocatalytic sensor and pattern recognition techniques
PublikacjaA response from an electrocatalytic gas sensor contains fingerprint information about the type of gas and its concentration. As a result, a single gas sensor can be used for the determination of different gases. However, information about the type of gas and its concentration is hidden in the unique shape of the current–voltage response and it is quite difficult to explore. One of the ways to get precise information about the measured...
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Optoelectronic system for monitoring of thin diamond layers growth
PublikacjaDevelopment of the optoelectronic system for monitoring of diamond/DLC (Diamond-Like-Carbon) thin films growth during mu PA ECR CVD (Microwave Plasma Assisted Electron Cyclotron Resonance Chemical Vapour Deposition) process is described. The multi-point Optical Emission Spectroscopy (OES) and Raman spectroscopy were employed as non-invasive optoelectronic tools. Dissociation of H-2 molecules, excitation and ionization of hydrogen...
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The importance of the shape of the protein-water interface of a kinesin motor domain for dynamics of the surface atoms of the protein
PublikacjaSingle kinesin motor domain immersed in water has been investigated using molecular dynamics. It has been found that local properties of water in solvation shell change along with the nature of neighboring protein surface. However, a detailed analysis leads to the conclusion that the geometrical features of hydrogen bonds and overall structure of kinesin hydration water is not very different from bulk water. The local values of...