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Optimization of a Fabric Phase Sorptive Extraction protocol for the isolation of six bisphenols from juice pouches to be analysed by high performance liquid chromatography coupled with diode array detector
PublicationFabric Phase Sorptive Extraction (FPSE) combined with high pressure liquid chromatography using to diode array detection (HPLC-DAD) was applied for the simultaneous determination of bisphenols (BPA, BPB, BPC, BPE, BPF, BPS) in juice pouches. The FPSE procedure was optimized with regards to the critical parameters that affect the performance of the method including the selection of the FPSE membrane type and size, adsorption time,...
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Sposób przygotowania roztworu chitozanu, kompozycja i sposób wytwarzania hydrożelowej membrany chitozanowej
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Chapter 4. Electricity generation from glucose microbial fuel cell
PublicationThe microbial fuel cell was constructed to generate electricity with simultaneous digestion of a glucose fuel by a bacterial biofilm. The decomposition of glucose resulted in releasing of electrons to an anode and to production of some by-products, e.g. metane or organic acids. It was found that maximum electric power density strongly depended on the proton transport through the proton exchange membrane seperating the anolyte and...
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Pharmaceutical applications of surfactants
PublicationIn this study we focused on biological activity of various surfactants. According to our research, they con act both as carriers as well as therapeutic agents. Depending on their concentration, they can create different structures in a solution, which influence their properties. Liposomes have a significant role in drug delivery system. Surfactants in from of bilayer are analogous to natural biological cell membrane.
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Calix[4]arenes appended with thioamide moieties as powerful tool for heavy metals recognition
PublicationSelectivity of new thioamide derivatives was assessed using those ligands as sensor materials in ion-selective membrane electrodes and tested towards Pb2+ - selectivity. The influence of the nature of the thioamide function (linear, branched or cyclic substituents) on their ionophoric properties was investigated. Electrodes based on cyclic thioamide moieties are promising analytical tools for monitoring Pb2+ concentration in natural...
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Pilot scale degradation study of 16 selected volatile organic compounds by hydroxyl and sulfate radical based advanced oxidation processes
PublicationThe studies of effective technologies for complete degradation of the volatile organic compounds (VOCs), are very important due to the high biotoxicity of the VOCs which makes the biological technologies ineffective. It also increases the risk of VOCs emission instead of their treatment when using open air biological technologies. In the present study, different types of Advanced Oxidation Processes (AOPs) were investigated for...
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O-substituted tetrahydroxamate derivatives of p-tert-butylcalix[4]arene as receptors for transition and heavy metal cations
PublicationTetrasubstituted O-hydroxamate derivatives of p-tert-butylcalix[4]arene were applied as active materials in ion-selective membrane electrodes and were tested towards Pb-selectivity. The electrodes gave near-Nernstian characteristics for Pb2+ cations. The selectivity coefficients were determined. The influence of plasticizer on the electrode behaviour was studied. The dependence of the chemical structure on selectivity coefficients...
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Mechanism of Solute and Thermal Characteristics in a Casson Hybrid Nanofluid Based with Ethylene Glycol Influenced by Soret and Dufour Effects
PublicationThis article models a system of partial differential equations (PDEs) for the thermal and solute characteristics under gradients (concentration and temperature) in the magnetohydrodynamic flow of Casson liquid in a Darcy porous medium. The modelled problems are highly non-linear with convective boundary conditions. These problems are solved numerically with a finite element approach under a tolerance of 10−8. A numerical algorithm...
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Messmethoden zur beurteilung der qualität von VoIP-verbindungen
PublicationPraca jest poświęcona tematyce QoS (Quality of Service) w sieciach IP. Na początku pracy opisano i porównano standaryzowane metody oceny jakości połączeń telefonicznych, tzn. MOS, PAMS, PSQM, PESQ, 3SQM, E-Modell. Następnie przedstawiono nowy efektywny system pomiarowy TraceView®:VoIP. Przy jego użyciu jest możliwy objektywny pomiar jakości usługi VoIP (Voice over IP) w sieciach IP. System ten umożliwia również dokonanie w...
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Self-Organization of Graft Copolymers and Retortable iPP-Based Nanoporous Films Thereof
PublicationPolyolefins might become inexpensive alternatives to the existing membranes based on polyethersulfone. Here we disclose the production of retortable, well-defined PP-based nanoporous membranes derived from amphiphilic graft copolymer precursors. The graft copolymers, containing a polypropylene backbone and polyester grafts, were obtained by grafting lactones, specifically δ-valerolactone and ε-caprolactone, from well-defined randomly...
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High temperature air/steam gasification of biomass in view of hydrogen rich gas production.
PublicationArtykuł przedstawia opis nowej i zaawansowanej metody konwersji termochemicznej biomasy i miejskich odpadów stałych w paliwo gazowe, bogate w wodór. W porównaniu z tradycyjnym procesem gazyfikacji, w metodzie tej wykorzystuje się powietrze/parę wodną przegrzane do wysokiej temperatury (powyżej 1300 st. C). Przegrzanie powietrza lub pary wodnej odbywa się z zastosowaniem ceramicznego przegrzewacza wysokotemperaturowego. W celu...
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Activated persulfate and peroxymonosulfate based advanced oxidation processes (AOPs) for antibiotics degradation – A review
PublicationSulfate radical AOPs (SR-AOP) were successfully utilized in degradation of antibiotics in water and wastewater treatment. The review discusses details on SR-AOPs mechanisms and applications for antibiotics degradation. The progress in this field was discussed, highlighting the most promising developments and remaining challenges. The applicability of SR-AOPs was summarized revealing the most susceptible and persistent to oxidation...
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Impedance investigations of amperometric gas sensor containing aprotic solvent
PublicationSkonstruowany został amperometryczny czujnik gazowy w układzie trójelektrodowym ze złotą elektrodą roboczą bezpośrednio napyloną na membranę Nafionową. W publikacji przedstawiono wyniki badań charakterystyk czujnika do oznaczania ditlenku siarki wypełnionego elektrolitem zawierającym różne względne zawartości DMSO/H2O. Wyniki badań impedancyjnych zostały przeanalizowane w oparciu o zaproponowany elektryczny układ zastępczy.
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Elastoplastic material law in 6-parameter nonlinear shell theory
PublicationWe develop the elastoplastic constitutive relations for nonlinear exact 6-parameter shell theory. A J2-type theory with strain hardening is formulated that takes into account asymmetric membrane strain measures. The incremental equations are solved using implicit Euler scheme with closest point projection algorithm. The presented test example shows the correctness of the proposed approach. Influence of micropolar material parameters...
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CHARAKTERYSTYKA WYMIANY CIEPŁA I OPORÓW PRZEPŁYWU OMYWANIA MIKROSTRUGAMI ROZWINIĘTEJ POWIERZCHNI
PublicationW artykule przedstawiono eksperymentalne badania kompaktowego wymiennika ciepła z intensyfikacją przejmowania ciepła przy użyciu mikrostrug. Niniejszy artykuł przedstawia projekt i testy prototypu, wymiennika ciepła typu mikrostrugowego. Modułowa konstrukcja wymiennika umożliwia zmianę wymiarów geometrycznych, a także zmianę materiału przegrody wymiennika ciepła. Metoda graficzna Wilsona została z zastosowana w celu określenia...
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Lipopolysaccharides: regulated biosynthesis and structural diversity
PublicationThe cell envelope of Gram-negative bacteria contains two distinct membranes, an inner (IM) and an outer (OM) membrane, separated by the periplasm, a hydrophilic compartment that includes a thin layer of peptidoglycan. The most distinguishing feature of such bacteria is the presence of an asymmetric OM with phospholipids located in the inner leaflet and lipopolysaccharides (LPSs) facing the outer leaflet. The maintenance of this...
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SIMULATION OF PROCEED® SURGICAL MESH APPLIED TO VENTRAL HERNIA REPAIR
PublicationIn the present research, Proceed® implant is considered. The system is subjected to short-time dynamic pressure load, similar to post-operative cough naturally occurring in human abdomen. The model refers to a clinical case of 5cm of hernia operated by Proceed implant fixed by 15 joints every 3cm around the orifice. The simulations of the implanted mesh are performed by means of the Finite Element Method. The implant is modelled...
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New bis(azobenzocrown)s with dodecylmethylmalonyl linkers as ionophores for sodium selective potentiometric sensors
PublicationNovel biscrowns 1 and 2 were synthesized from 13-membered azobenzocrown ethers containing bromoalkylenoxy chains in para position relative to the azo group. The synthesized diester molecules are dodecylmethylmalonic acid derivatives differing by the linker length. The synthesized compounds have the potential of being used as sodium ionophores in ion-selective electrodes. They were characterized and used as ionophores in classic...
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The estimation of fish lenght distribution from its acoustical measures
PublicationThe paper concerns the problem of estimating fish length PDF from its target strength PDF obtained from acoustic surveys. It has been shown that the target strength of single fish can be treated in the first approximation as a finction of two variables: one, which depends on fish size and the other, which depends on its angular orientation (aspect). Extending this simplified relationship to the case of fish populations allows to...
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Galerkin formulations with Greville quadrature rules for isogeometric shell analysis: Higher order elements and locking
PublicationWe propose new Greville quadrature schemes that asymptotically require only four in-plane points for Reissner-Mindlin (RM) shell elements and nine in-plane points for Kirchhoff-Love (KL) shell elements in B-spline and NURBS-based isogeometric shell analysis, independent of the polynomial degree of the elements. For polynomial degrees 5 and 6, the approach delivers high accuracy, low computational cost, and alleviates membrane and...
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Nonlinear FEM analysis of irregular shells composed of fiber metal laminates
PublicationThe paper deals with the analysis of failure initiation in shells made of Fiber Metal Laminates (FML). The elas-tic material law for orthotropic lamina is stated accounting for asymmetric in-plane stress and strain measures. The asymmetry results from the employed general nonlinear 6-field shell theory where the generalized dis-placements involve the translation and the proper rotation field. The novelty of the presented results...
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Modeling of active fiber Bragg grating underwater acoustic sensor.
PublicationW pracy przedstawiono wyniki modelowania nowego typu przetwornika hydroakustycznego wykorzystującego światłowodową siatkę Bragga. Siatka ta, domieszkowana jonami pierwiastków ziem rzadkich, pracuje jako laser z rozłożonym sprzężeniem zwrotnym, co pozwala na znaczne zwiększenie czułości tego prztwornika w porównaniu z rozwiązaniami wykorzystującymi siatki pasywne. W celu uzyskania równomiernego rozkładu naprężeń siatki zastosowano...
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Numerical Methods for Partial Differential Equations
e-Learning CoursesCourse description: This course focuses on modern numerical techniques for linear and nonlinear elliptic, parabolic and hyperbolic partial differential equations (PDEs), and integral equations fundamental to a large variety of applications in science and engineering. Topics include: formulations of problems in terms of initial and boundary value problems; finite difference and finite element discretizations; boundary element approach;...
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Charakterystyka areodynamiczna membranowego przekrycia wiszącego.
PublicationArtykuł przedstawia charakterystykę aerodynamiczną membranowego przekrycia wiszącego. Prezentowane są dwie koncepcje przyjmowania wartości współczynnika aerodynamicznego. Pierwsza z koncepcji bazuje bezpośrednio na testach laboratoryjnych druga zaś wykorzystuje uproszczone podejście normowe.This paper presents the aerodynamic characteristics of membrane hanging roof. The two concepts of taking the value of the aerodynamic factor...
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Influence of the presence of rhamnolipids and ionic cross-linking conditions on the mechanical properties of alginate hydrogels.
Open Research DataThe dataset contains the results of determination the effect of rhamnolipids concentration, calcium chloride concentration and ionic cross-linking time on the mechanical properties of alginate hydrogels prepared by immersing the alginate mixture limited by the dialysis membrane in an appropriate cross-linking solution containing calcium ions. The mechanical...
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Zminiaturyzowane czujniki potencjometryczne jako detektory do elektroforezy kapilarnej
PublicationWykorzystanie czujników potencjometrycznych jako detektorów w chromatografii cieczowej (LC) i elektroforezie kapilarnej (CE), będące interesującym rozwiązaniem nie jest praktycznie stosowane. Przeprowadzono elektroforezę kapilarną związków z grupy leków antyhistaminowych i antydepresantów stosując jako zminiaturyzowany czujnik potencjometryczny elektrodę metaliczną z polimerową membraną pozostającą w bezpośrednim kontakcie z powierzchnią...
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Modeling of active fiber Bragg grating sensors
PublicationW artykule omówiono działanie przetwornika hydrofonu wykorzystującego profilowaną membranę sprzężoną z aktywną światłowodową siatką Bragga. W wyniku modelowania, wykonanego Metodą Elementów Skończonych, stwierdzono występowanie gradientów naprężeń wzdłuż siatki. Opracowano program do modelowania pasywnych i aktywnych światłowodowych siatek Bragga wykorzystujący metodę modów sprzężonych. Przedstawiono charakterystyki widmowe pasywnych...
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Inception and Propagation of Electrical Trees in the Presence of Space Charge in HVAC Extruded Cables
PublicationThis paper presents the space charge impact on the inception and propagation of electrical trees in cross-linked polyethylene (XLPE) insulation via simulations and experimentation. A 3D finite element analysis (FEA)-based modeling is proposed to simulate electrical trees via a needle embedded on the XLPE insulation. The proposed FEA model demonstrates the influence of the space charge magnitude and polarity on the initiation of...
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Radio Channel Measurements in 868 MHz Off-Body Communications in a Ferry Environment
PublicationIn this paper, a characterization of the 868 MHz off-body radio channel in BANs is presented. Measurements were carried out in a ferry environment using a specific set-up. A method for path loss using radio distance measurements (RDMs) was developed. It allows to automate the measurements process and make it independent from the variable speed of a moving person. Based on the observed path loss as a function of distance, the obtained...
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A Flexible Nafion Coated Enzyme‐free Glucose Sensor Based on Au‐dimpled Ti Structures
PublicationThe detection of glucose at low concentrations using electrochemical sensors is of great importance due to the possibility of using different human body fluids than blood, such as e.g. urine, saliva, sweat or tears. The interest behind those biofluids is related to their utility in non-invasive sugar determination. In this work, we present flexible, fully biocompatible electrode material based on Au nanoparticles immobilized onto...
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Regulated Assembly of LPS, Its Structural Alterations and Cellular Response to LPS Defects
PublicationDistinguishing feature of the outer membrane (OM) of Gram-negative bacteria is its asymmetry due to the presence of lipopolysaccharide (LPS) in the outer leaflet of the OM and phospholipids in the inner leaflet. Recent studies have revealed the existence of regulatory controls that ensure a balanced biosynthesis of LPS and phospholipids, both of which are essential for bacterial viability. LPS provides the essential permeability...
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Dissection of σE‐dependent cell lysis in Escherichia coli: roles of RpoE regulators RseA, RseB and periplasmic folding catalyst PpiD
PublicationTo understand the mechanism of sigma(E)-dependent cell lysis, we examined the consequences of deletion derivatives of rpoE regulators rseA, rseB and rseC on sigma(E) transcription, on levels of free versus membrane-bound sigma(E) and on OMP-biogenesis limiting factor(s) that could impact cell lysis. RT-PCR showed that individual nonpolar DeltarseA and DeltarseB increased the rpoE expression to varying extents, with pronounced induction...
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Investigation of poly(3,4-ethylenedioxythiophene) deposition method influence on properties of ion-selective electrodes based on bis(benzo-15-crown-5) derivatives
PublicationGlassy carbon electrodes modified by conductive polymers and membrane with derivatives of bis(benzo-15-crown-5) were tested as solid contact ion selective electrodes for K+ ions concentration determination. PEDOT with PSS, Cl- and ClO4- counter ions was electrochemically deposited onto glassy carbon substrates using four different electrochemical approaches (potentiostatic, galvanostatic, potentiodynamic and potentiostatic pulses)....
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Does the chemical modification of Nystatin A1 affect the drug's ability to overcome the multidrug resistance of fungi?
PublicationAlthough the contemporary medicine keeps moving forward, disseminated infections caused by fungal pathogens are an emerging challenge. The dramatic rise of fungal diseases, especially the most life-threatening systemic mycoses is associated with a permanently growing number of immunodeficient patients. Undoubted difficulties in the treatment of fungal infections are caused by lack of highly effective and selective antifungal drugs,...
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Powstawanie oceanicznych aerozoli siarczanowych i ich wpływ na środowisko
PublicationW pracy przedstawiono problem wpływu aerozoli morskich na środowisko i kształtowanie klimatu. Opisano cykl biogeochemiczny siarki w przyrodzie i źródła jej emisji. Główną uwagę poświecono związkom siarki powstającym w morzach i oceanach, a w szczególności dimetylosulfidowi (DMS) i procesom jego tworzenia. Wykazano jego znaczącą rolę w tworzeniu aerozoli siarczanowych. Przedstawiono hipotezę CLAW, która uwzględniając obieg związków...
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Funkcje fizjologiczne i możliwości zastosowań trehalozy
PublicationTrehaloza jest disacharydem naturalnego pochodzenia zbudowanym z dwóch reszt glukozy połączonych wiązaniem 1,1 glikozydowym. Cukier ten charakteryzuje się dużą zdolnością do stabilizowania białek i membran biologicznych podczas zamrażania i odwadniania komórek i w związku z tym zabezpiecza je przed niekorzystnym oddziaływaniem środowiska. Stwarza to także omówione w artykule duże możliwości zastosowania trehalozy w medycynie,...
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Local atomic order in low Pt-content nanocatalysts investigated in situ by XAS
PublicationThe unique features of X-ray absorption spectroscopy allow investigations of nanosized catalysts for fuel cells under working conditions. We present the results of an experiment carried out on a low Pt content electrocatalyst supported by a mesoporous heteropolyacid salt and used at the cathode of a proton exchange membrane fuel cell (PEMFC). The analysis of the EXAFS signal at the Pt L3-edge indicates that upon operating the fuel...
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Permeation and sorption properties of poly(ether-block-amide) membranesfilled by two types of zeolites
PublicationThe experimental study of transport properties of mixed matrix membranes (MMMs) based on PEBA-4033 with two types of zeolites is reported. Gas (CO2, O2, N2) and vapor (benzene, toluene, methanol, water) permeation measurements were performed using the differential flow permeameter at temperature of 298.15 K and at atmospheric pressure. Gas/vapor permeation was monitored by measuring the changes of the thermal conductivity of carrier...
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Układ awaryjnego zasilania oparty na ogniwach paliwowych PEFC zasilany wodorem i metanolem
PublicationGłównymi elementami badanego układu zasilania są dwa moduły ogniw paliwowych PEFC typu Nexa kanadyjskiej firmy Ballard o mocy 1,2 kW każdy. Badany układ został wyposażony w reformer paliwowy firmy Genesis Fueltech model 20 L, w którym do wytworzenia czystego wodoru wykorzystuje się unikatową metodę przetwarzania wodnego roztworu metanolu opartą na połączeniu wysokociśnieniowego reformingu parą wodną oraz użyciu membrany separującej....
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PTD4 Peptide Increases Neural Viability in an In Vitro Model of Acute Ischemic Stroke
PublicationIschemic stroke is a disturbance in cerebral blood flow caused by brain tissue ischemia and hypoxia. We optimized a multifactorial in vitro model of acute ischemic stroke using rat primary neural cultures. This model was exploited to investigate the pro-viable activity of cell-penetrating peptides: arginine-rich Tat(49–57)-NH2 (R49KKRRQRRR57-amide) and its less basic analogue, PTD4 (Y47ARAAARQARA57-amide). Our model included glucose...
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Checkpoints that regulate balanced biosynthesis of lipopolysaccharide and its essentiality in Escherichia coli
PublicationThe outer membrane (OM) of Gram-negative bacteria, such as Escherichia coli, is essential for their viability. Lipopolysaccharide (LPS) constitutes the major component of OM, providing the permeability barrier, and a tight balance exists between LPS and phospholipids amounts as both of these essential components use a common metabolic precursor. Hence, checkpoints are in place, right from the regulation of the first committed step...
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Molecular Strategy for Survival at a Critical High Temperature in Eschierichia coli
PublicationThe molecular mechanism supporting survival at a critical high temperature (CHT) in Escherichia coli was investigated. Genome-wide screening with a single-gene knockout library provided a list of genes indispensable for growth at 47°C, called thermotolerant genes. Genes for which expression was affected by exposure to CHT were identified by DNA chip analysis. Unexpectedly, the former contents did not overlap with the latter except...
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Torsional elasticity and energetics of F1-ATPase
PublicationFoF1-ATPase is a rotary motor protein synthesizing ATP from ADP driven by a cross-membrane proton gradient. The proton flow through the membrane-embedded Fo generates the rotary torque that drives the rotation of the asymmetric shaft of F1. Mechanical energy of the rotating shaft is used by the F1 catalytic subunit to synthesize ATP. It was suggested that elastic power transmission with transient storage of energy in some compliant...
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Direct injection liquid chromatography-mass spectrometry (DI-LC-MS) analysis for rapid lipidomic profiling of extracellular vesicles
PublicationExtracellular vesicles (EVs) are small, spherical particles produced by eukaryotic and prokaryotic cells, surrounded by a bilayer membrane and carrying various bioactive molecules, such as proteins, surface receptors, membrane and soluble proteins, lipids, and nucleic acids. EVs are of substantial interest because of their important roles in cell communication, epigenetic regulation and possible application in disease diagnosis...
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Comparison of different techniques for extracting Polychlorinated Biphenyls from bottom sediment samples using Isotope Dilution Mass Spectrometry
PublicationIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. The main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sediment reference material (METRANAL 2) with the use of different solvents (dichloromethane, hexane, and toluene); the process...
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Badania nad potencjometrycznymi sensorami smaku
PublicationPrzedstwiono badania nad 5-kanałowym sensorem smaku kwasnego, zbudowanym z elektrod z membranami polimerowo - lipidowymi zawierającymi odpowiednie lipidy. Stwierdzono, że sensor ten jest bardzo czuły na zmainy stężenia kwasu cytrynowego, natomiast wykazuje nieco gorszą czułosc na obecnosć kwasu octowego. Stwirdzono dobrą trwałosć membran oraz powtarzalnośc otrzymanych wyników. Wydaje się, że badane układy mogą byc wykorzystane...
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Iron(III)-selective materials based on a catechol-bearing amide for optical sensing
PublicationThe synthesis and ion-binding properties of a new amide L derived from 3,4-dihydroxybenzoic acid are described. Due to the presence of a catechol unit, the compound interacts selectively with iron(III) in organic solvent (dimethyl sulfoxide, DMSO) to produce a color change from pale yellow to green. The incorporation of the ligand L into polymeric matrices or its encapsulation into surfactant-based spheres enables analyte detection...
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Functionalized azobenzocrown ethers as sensor materials—The synthesis and ion binding properties
PublicationNew 13- and 16-membered azobenzocrown ethers with aromatic amino, amide, ether–ester or ether–amide residue in para position to an azo moiety were obtained. Acid–base properties and ion binding ability of the colored compounds were studied by spectroscopic methods: UV–vis, fluorimetry and 1H NMR spectroscopy. Selected azobenzocrowns were tested as ionophores in ion-selective membrane electrodes (ISEs) – classic and miniature all...
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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
PublicationThe 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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Modeling of subarachnoid space width change caused by blood circulation in brain vessels
PublicationThe subarachnoid space is an anatomic space, lying in the central nervous system, between the arachnoid membrane and the pia mater. It is filled with cerebrospinal fluid, which protects and nourishes the brain. The pathological disorder of the subarachnoid space (i.e. increase or decrease of its width) a ects the nervous system. Therefore, it is important to diagnose the width changes of the subarachnoid space. One way to support...