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Preparation of DNA films for studies under vacuum conditions
PublikacjaExperiments were carried out to determine the optimum conditions required for the preparation of uniform films of supercoiled plasmid DNA to be used in irradiation experiments under high vacuum conditions. Investigations reveal that significant damage to the DNA molecules occurs due to the evacuation process when films were formed from DNA samples in ultra high purity water only. A variety of bases were tested for their possible...
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The influence of the substrate temperature on the preparation of DNA films for studies under vacuum conditions
PublikacjaExperiments were carried out to determine the dependence of the physical form of supercoiled DNA films on the initial temperature of the substrate. Such films are often used in irradiation experiments involving low energy particles, like electrons or photons. In order to obtain absolute values for cross sections for such experiments, the spatial distribution of the sample in the film has to be well estimated. These investigations...
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Aluminium in glacial meltwater demonstrates an association with nutrient export (Werenskiöldbreen, Svalbard)
PublikacjaThe aluminium (Al) cycle in glacierised basins has not received a great deal of attention in studies of biogeochemical cycles. As Almay be toxic for biota, it is important to investigate the processes leading to its release into the environment. It has not yet been ascertained whether filterable Al (passing through a pore size of 0.45 m) is incorporated into biogeochemical cycles in glacierised basins. Our study aims to determine...
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Particle shape dependence in 2D granular media
PublikacjaParticle shape is a key to the space-filling and strength properties of granular matter. We consider a shape parameter eta describing the degree of distortion from a perfectly spherical shape. Encompassing most specific shape characteristics such as elongation, angularity and non-convexity, eta is a low-order but generic parameter that we used in a numerical benchmark test for a systematic investigation of shape dependence in sheared...
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Structure-Activity Relationships in Two-Electron Reduction of Quinones
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Quinolinium tetrachloroferrate(III)
PublikacjaZbadano strukturę krystaliczną tetrachlorożelazianu chinoliny. Jon tetrachlorożelazianowy leży na płaszczyźnie symetrii, a kation chinolinowy wykazuje orientacyjne nieuporządkowanie. W strukturze występują oddziaływania C-H...Cl oraz Fe-Cl...π.
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Wyznaczanie czasów stygnięcia przy spawaniu pod wodą metodą lokalnej komory suchej
PublikacjaPrzedmiotem pracy było wyznaczenie zależności empirycznej umożliwiającej obliczanie czasu stygnięcia w zakresie 800-500° C przy spawaniu pod wodą metodą lokalnej komory suchej. Problem rozwiązano przy zastosowaniu teorii planowania badań. Określono ilościowy wpływ warunków spawania: grubości elementów spawanych oraz energii liniowej spawania na czas stygniecia w zakresie temperatur 800-500°C. Równania otrzymane na drodze analiz...
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Determination of the Diffusion Coefficient of Lithium Ions in Graphite Coated with Polymer-Derived SiCN Ceramic
PublikacjaPraca dotyczy wyznaczenia wsółczynnik adyfuzji jonów litu w materiale elektrodowym składającym się z grafitu pokrytego materiałem ceramicznym krzemo-azotkiem węgla (SiCN). Wartość współczynnika dyfuzji zmierzono elektrochemicznie technikami: woltamperometrii cyklicznej (CV), elektrochemicznej spektrodkopii impedancyjnej (EIS) oraz miareczkowania galwanostatycznego (GITT). Materiał otrzymano na drodze pirolizy mieszaniny grafit:polimer...
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N,N' -Bis(2-pirydyl)benzene-1,2-diamine.
PublikacjaN,N' -Bis(2-pirydylo)benzeno-1,2-diamina na skutek zahamowania swobodnej rotacji wokół częściowo podwójnego wiązania C-N pomiędzy resztami aminową oraz pirydynową może przyjąć dwie konformacje. Konformacja E jest stabilizowana przez cykliczne wiązanie wodorowe pomiędzy protonem grupy aminowej i atomem azotu pirydyny (N-H...N); tworzy się centrosymetryczny motyw typu pierścienia ośmioczłonowego. Druga konformacja Z charakteryzuje...
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Stress strain relations and modulus of elascity of two stage concrete.
PublikacjaOmówiono badania doświadczalne przeprowadzone dla betonu dwuetapowego. Beton wykonano z trzech różnych kruszyw przy zastosowaniu trzech różnych proporcji w/c i c/p. Wyznaczono związki pomiędzy naprężeniami i odkształceniami. Na drodze statystycznej opracowano wzory umożliwiające wstępne szacowanie wartości siecznego modułu Younga. Ponieważ metoda dwuetapowa pozwala na zachowanie kontaktu pomiędzy poszczególnymi elementami kamiennego...
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Badania cech reologicznych mieszanek mineralno-asfaltowych podczas pełzania przy zginaniu w niskich temperaturach.
PublikacjaReferat przedstawia metodykę oraz wyniki badań cech reologicznych mieszanek mineralno-asfaltowych w zakresie temperatur od -10 st C do +20 st C. W badaniach wykorzystano metodę zginania belek obciążonych stałą siłą skupioną przyłożoną w środku rozpiętości belki. Zastosowano dwa typy mieszanek mineralno-asfaltowych: beton asfaltowy z asfaltem zwykłym i mastyks grysowy SMA z asfaltem modyfikowanym. Do wyznaczenia cech reologicznych...
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Influence of grout proportions on modulus of elascity of two-stage concrete
PublikacjaOmówiono badania doświadczalne przeprowadzone dla betonu dwuetapowego. Beton wykonano z kruszywa otoczakowego przy zastosowaniu trzech różnych proporcji w/c i c/p. Na drodze statystycznej opracowano prosty wzór umożliwiający wstępne szacowanie wartości siecznego modułu Younga. Ponieważ metoda dwuetapowa pozwala na zachowanie kontaktu pomiędzy poszczególnymi elementami kamiennego szkieletu wypełniającego formę, wytrzymałość uzyskanego...
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Ellipsometric study of carbon nitride films deposited by DC-magnetron sputtering
PublikacjaWe report the optical properties of a carbon nitride (CNx) film as a function of nitrogen concentration (N/C) of the deposited film. As nitrogen concentration is increased (N/C ratio) in a CNx film, the refractive index and band gap also increase. The real and imaginary parts, n and k (refractive index and extinction coefficient) of the complex refraction index of carbon nitride films were determined by spectroscopic ellipsometry...
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A new cold-active β-galactosidase from Arthrobacter sp. S3* - gene cloning, overexpression, purification and properties
PublikacjaA psychrotrophic bacterium producing a cold-active β-galactosidase was isolated from Spitsbergen soil and classified as Arthrobacter sp. S3*. The gene encoding β-galactosidase was isolated from the genomic DNA library, sequenced, cloned, expressed in Escherichia coli, purified by ion exchange chromatography and characterized. The Arthrobaster sp. S3* β-galactosidase is a homotrimeric enzyme composed of 74,4 kDa subunits. It is...
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Superconductivity on a Bi Square Net in LiBi
PublikacjaWe present the crystallographic analysis, superconducting characterization and theoretical modeling of LiBi, that contains the lightest and the heaviest nonradioactive metal. The compound crystallizes in a tetragonal (CuAu-type) crystal structure with Bi square nets separated by Li planes (parameters a = 3.3636(1)Å and c = 4.2459(2) Å, c/a = 1.26). Superconducting state was studied in detail by magnetic susceptibility and heat...
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ALTERNATIVE, DIRECT SYNTHESIS METHOD OF THE CERAMIC SOLID SOLUTIONS BASED ON BaTiO3 THROUGH A HIGH ENERGY BALL MILLING
PublikacjaPolycrystalline samples BaTiO3 and the solid solutions Ba0.9Sr0.1TiO3, Ba0.9Sr0.1Ti0.9Sn0.1O3, Ba0.9Sr0.1Ti0.8Sn0.2O3 were obtained by means of a mechanochemical treatment based on the high-energy ball milling technique and next a high temperature solid state reaction method. The influence of synthesis condition on microstructural, dielectric and ferroelectric properties of obtained solid solutions were investigated. The structure...
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Voriconazole-Based Salts Are Active against Multidrug-Resistant Human Pathogenic Yeasts
PublikacjaVoriconazole (VOR) hydrochloride is unequivocally converted into VOR lactates and valinates upon reaction with silver salts of organic acids. This study found that the anticandidal in vitro activity of these compounds was comparable or slightly better than that of VOR. The Candida albicans clinical isolate overexpressing CaCDR1/CaCDR2 genes, highly resistant to VOR, was apparently more susceptible to VOR salts. On the other hand,...
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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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The effect of preliminary creep-strain on material behavior under LCF tension/compression and pure torsion regimes
PublikacjaThis paper presents the results of experimental tests of monotonic tension and torsion, creep-rupture and preliminary creep at 200C and 300C, as well as low-cycle fatigue of 2024 T3511 aluminum alloy. The fatigue process was conducted at room temperature for uniaxial tension/compression and torsion. The as-received material and pre-deformed material were also investigated during creep at elevated temperature. Basic monotonic,...
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Electron-scattering cross sections for selected alkyne molecules: Measurements and calculations
PublikacjaWe report cross-section results from experimental and theoretical studies on electron collisions with 1-butyne (HC≡C–CH2CH3) and acetylene (HC≡CH) molecules and from computations for a propyne (HC≡C–CH3) molecule. Absolute grand -total electron-scattering cross sections (TCSs) were measured at impact energies ranging from about 0.5 to 300 eV using the linear electron-transmission method. The TCS energy curve for 1-butyne has a...
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Screening evaluation of the quality of commercially available cigars, cigarillos, and bidis based on emission levels of selected terpenes and terpenoids
PublikacjaThe aim of the research was to verify the use of the solvent-free, non-destructive and easy to operate analytical method to study and compare the emissions of 16 representatives of terpenes and terpenoids from commercially available cigars, cigarillos and bidis − a potential screening analysis for the quality of combustible tobacco products. To assess the amount of organic compounds emitted to the gaseous phase from investigated...
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Window frame integrable air recuperation minichannel/minigap heat exchanger
PublikacjaThis article describes an evaluation of mini heat exchangers operation as a decentralized mechanical ventilation system with recuperative heat recovery that can be integrated into the window frame. The relatively small yet efficient air recuperation system allows for retrofitting existing buildings by reducing the overall energy consumption and thus the CO2 emissions. The proposed design, unlike existing systems, is easy to scale...
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A novel concept of enhanced direct-contact condensation of vapour- inert gas mixture in a spray ejector condenser
PublikacjaAn analytical model of direct steam condensation (DCC) in the novel idea of spray ejector condenser (SEC) in the presence of inert gas has been developed. It is based on continuity, momentum and energy equations for the steam-carbon dioxide mixture and direct contact condensation mechanisms due to heat transfer and concentration. Crucial in the process of DCC is atomisation of the motive fluid in the ejector. The effect of atomised...
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The role of the combined nitrogen-sulfur-carbon cycles for efficient performance of anammox-based systems
PublikacjaThe combined anammox/mixotrophic denitrification process was conducted in two granular sequencing batch reactors (SBRs) during a 200-day operation. Both reactors were fed with synthetic medium, but SBR2 was enriched with additional sulfate (SO4 2 ) which influenced sulfate reduction ammonium oxidation (SRAO) and heterotrophic reduction of SO4 2 by sulfate reducing bacteria. It was hypothesized that the addition of SO4 2 could...
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Late Aortic Remodeling after Endovascular Repair of Complicated Type B Aortic Dissection—TEVAR Protects Only the Covered Segment of Thoracic Aorta
PublikacjaIntroduction: TEVAR is the preferred way of treatment of complicated type B aortic dissection. The purpose of the study was to assess the impact of TEVAR on aortic remodelling in the thoracic and abdominal segment in long-term follow-up. Methods: 23 patients with complicated type B aortic dissection were treated by TEVAR in years 2004-2012 in our Department. Aortic remodelling was rated based on preoperative and final follow-up...
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Bio-Based Polyurethane Networks Derived from Liquefied Sawdust
PublikacjaThe utilization of forestry waste resources in the production of polyurethane resins is a promising green alternative to the use of unsustainable resources. Liquefaction of wood-based biomass gives polyols with properties depending on the reagents used. In this article, the liquefaction of forestry wastes, including sawdust, in solvents such as glycerol and polyethylene glycol was investigated. The liquefaction process was carried...
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Improvement of Oxygen Electrode Performance of Intermediate Temperature Solid Oxide Cells by Spray Pyrolysis Deposited Active Layers
PublikacjaIntermediate temperature solid oxide fuel cells oxygen electrodes are modified by active interfacial layers. Spray pyrolysis is used to produce thin (≈500 nm) layers of mixed ionic and electronic conductors: Sm0.5Sr0.5CoO3−δ (SSC), La0.6Sr0.4CoO3−δ (LSC), La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF), and Pr6O11 (PrOx) on the electrode–electrolyte interface. The influence of the annealing temperature on the electrode polarization (area specific...
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Mass Spectrometric Identification of 13C-labeled Metabolites During anaerobic Propanoic Acid Oxidation
PublikacjaBiowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...
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Low temperature rotary Stirling engine: conceptual design and theoretical analysis
PublikacjaThe use of low-temperature energy sources for electricity generation demands a dual focus: a substantial enhancement in the efficiency of energy conversion devices and a reduction in system production costs. Particularly in scenarios where low-temperature energy sources are scarce, this factor can be pivotal in facilitating widespread adoption of such technologies. The Stirling engine emerges as a promising solution capable of...
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Phosphate tricyclic coumarin analogs as steroid sulfatase inhibitors: synthesis and biological activity.
PublikacjaIn the present work, we report convenient methods for the synthesis and biological evaluation of phosphate tricyclic coumarin derivatives as potential steroid sulfatase inhibitors. The described synthesis includes the straightforward preparation of 7-hydroxy-2,3-dihydro-1H-cyclopenta[c]chromen-4-one, 3-hydroxy-7,8,9,10-tetrahydro-6H-benzo[c]chromen-6-one and 3-hydroxy-8,9,10,11-tetrahydro-7H-cyclohepta[c]chromen-6-one modified...
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Local impedance imaging of boron-doped polycrystalline diamond thin films
PublikacjaLocal impedance imaging (LII) was used to visualise surficial deviations of AC impedances in polycrystalline boron-doped diamond (BDD). The BDD thin film electrodes were deposited onto the highly doped silicon substrates via microwave plasma-enhanced CVD. The studied boron dopant concentrations, controlled by the [B]/[C] ratio in plasma, ranged from 1 × 1016 to 2 × 1021 atoms cm−3. The BDD films displayed microcrystalline structure,...
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Study of microstress state of P91 steel using complementary mechanical Barkhausen, magnetoacoustic emission, and X-ray diffraction techniques
PublikacjaThe paper deals with assessment of microstress state of martensite P91 steel using three complementary techniques: mechanical Barkhausen emission, magnetoacoustic emission (MAE), and X-ray diffraction (XRD) profile analysis. Magnetic coercivity Hc and microstructure were investigated with inductive magnetometry and magnetic force microscopy (MFM), respectively. Internal stress level of P91 steel was modified by heat treatment....
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Production of essential oils from in vitro cultures of Caryopteris species and comparison of their concentrations with in vivo plants
PublikacjaThe chemical composition of hydrodistilled essential oils obtained from aerial parts and roots of selected Caryopteris (‘bluebeard’) species (C. incana, C. mongolica, Caryopteris 9 clandonensis), as well as the newly established in vitro shoot and adventitious root cultures of the above plants, was analyzed by gas chromatography– mass spectrometry. Essential oil content and composition differed significantly depending on the type...
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The Impact of Different Drying Methods on the Metabolomic and Lipidomic Profiles of Arthrospira platensis
PublikacjaDrying is an inseparable part of industrial microalgae production. In this work, the impacts of eight different drying methods on the metabolome and lipidome of Arthrospira platensis were investigated. The studied drying methods were freeze drying (FD), sun drying (SD), air drying at 40 and 75 °C (AD′ and AD″), infrared drying at 40 and 75 °C (IRD′ and IRD″), and vacuum drying at 40 and 75 °C (VD′ and VD″). Results gathered by...
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Superconductivity in a breathing kagome metals ROs2 (R = Sc, Y, Lu)
PublikacjaWe have successfully synthesized three osmium-based hexagonal Laves compounds ROs2 (R = Sc, Y, Lu), and discussed their physical properties. LeBail refinement of pXRD data confirms that all compounds crystallize in the hexagonal centrosymmetric MgZn2- type structure (P63/mmc, No. 194). The refined lattice parameters are a = b = 5.1791(1) Å and c = 8.4841(2) Å for ScOs2, a = b = 5.2571(3) Å and c = 8.6613(2) Å for LuOs2 and a =...
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London penetration depth in local pair superconductors
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Nuclear magnetic relaxation and d-wave pairing in an extended Hubbard model with diagonal disorder
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Response of the local pair superconductor to the static vector potential at finite wave length
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Conductivity and superconductivity of (Bi,Pb)–Sr–Ca–Cu–O
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A resistivity peak close to Tc in Nd2−xCexCuO4−y single crystals
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Scanning tunneling microscopy and spectroscopy study of Nd2−xCexCuO4−y
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Ni2X2 (X=pnictide, chalcogenide, or B) based superconductors
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Study of superconductivity in a wide range of Ce doping in Nd-214 system
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Surface studies of twinned of YBa2Cu3O7−δ crystals
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Structural properties of superconducting PrBa2Cu3O7−δ single crystals
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In-plane and out-of-plane temperature dependencies of the resistivity in single crystals and films of Nd2CuO4
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Influence of the improved reduction technique on superconductivity in Nd1.85Ce0.15Cu1±yO4−δ
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Superconductivity in PrBa2Cu3O7−δ single crystals after high-temperature thermal treatment
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Growth and characterization of PrBa2Cu3O7-δ single crystals
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Electronic structure of PrBa2Cu3O7 after high-pressure compressionfrom first principles
PublikacjaW pracy zbadano wpływ ściskania wysokociśnieniowego (P=9GPa) na elektronową strukturę pasmową, rozkład ładunku i momenty magnetyczne w pełni utlenionego stechiometrycznego układu PrBa2Cu3O7. Zaobserwowano następujące zmiany wywołane ściskaniem: (1) zmniejszoną gęstość stanów (DOS) na poziomie Fermiego Ef, (2) zwiększona różnicę pomiędzy wartościami DOS dla stanów "spin-up" i "spin-down" w najbliższym otoczeniu Ef, (3) zmniejszone...