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Research of chitosan coatings deposited by electrophoretic deposition method at various voltage and time parameters
PublikacjaThe aim of this research is to estimate the electrophoretic deposition main parameters, such as voltage and time duration, that will provide optimal characteristics of the surface layer. Chitosan coatings were synthesized on biomedical Ti13Zr13Nb alloys at 20 V and 30 V and with deposit times of 2min, 5 min, 10 min, and 15 min. Evaluation of the coating was performed by using Scanning Electron Microscope (SEM), Energy-Dispersive...
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Bearing capacity of working platform using distinct layout optimization method
PublikacjaBearing capacity of the working platforms from sandy soil resting on NC and OC clays was analyzed using LimitState GEO program. Different failure modes are considered using distinct layout optimization (DLO) method, which forms the upper bound solution of limit state analysis. Different mechanisms of failure were observed as a function of the platform thickness, angle of internal friction of the platform material and undrained...
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The speciation of organotin compounds in sediment and water samples from the port of Gdynia
PublikacjaOrganotin compounds (OTC) are toxic towards all living organisms. The application of organitin-based antifouling systems is becoming the main source of OTC in the ocean. Harbor sediments and water contain large deposits of organotin compounds due to application of antifouling systems in the shipping industry. OTC contamination presents a potential risk to the marine environment. Sediment and water samples were collected in 2009...
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Absolute Photoabsorption Cross-Sections of Methanol for Terrestrial and Astrophysical Relevance
PublikacjaWe investigate the methanol absorption spectrum in the range 5.5–10.8 eV to provide accurate and absolute cross-sections values. The main goal of this study is to provide a comprehensive analysis of methanol electronic-state spectroscopy by employing high-resolution vacuum ultraviolet (VUV) photoabsorption measurements together with state-of-the-art quantum chemical calculation methods. The VUV spectrum reveals several new features...
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Investigating the effects of structural pounding on the seismic performance of adjacent RC and steel MRFs
PublikacjaAn insufficient separation distance between adjacent buildings is the main reason for structural pounding during severe earthquakes. The lateral load resistance system, fundamental natural period, mass, and stiffness are important factors having the influence on collisions between two adjacent structures. In this study, 3-, 5- and 9-story adjacent reinforced concrete and steel Moment Resisting Frames (MRFs) were considered to investigate...
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Electrochemical determination of nitroaromatic explosives at boron-doped diamond/graphene nanowall electrodes: 2,4,6-trinitrotoluene and 2,4,6-trinitroanisole in liquid effluents
PublikacjaThe study is devoted to the electrochemical detection of trace explosives on boron-doped diamond/graphene nanowall electrodes (B:DGNW). The electrodes were fabricated in a one-step growth process using chemical vapour deposition without any additional modifications. The electrochemical investigations were focused on the determination of the important nitroaromatic explosive compounds, 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitroanisole...
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Betaine and L-carnitine ester bromides: Synthesis and comparative study of their thermal behaviour and surface activity
PublikacjaSix esters of both betaine and L-carnitine bromides, featuring alkyl groups ranging from C8 to C18 in length, have been synthesized. The thermal behaviour of these twelve bio-based salts has been analyzed and compared by thermal gravimetric analysis and differential scanning calorimetry. The L-carnitine alkyl ester bromides melted below 100 C and can hence be considered ionic liquids (ILs) with full rights. Conversely, the betaine...
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ANALYSIS OF THE IMPACT OF THE PLANNED SEWAGE DISCHARGE FROM THE ‘NORTH’ POWER PLANT ON THE VISTULA WATER QUALITY
PublikacjaThe paper presents results of analysis of the industrial sewage discharge impact from the ‘North’ Power Plant on the Vistula water quality around 45+330 of the river kilometer. For the analysis, the two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined....
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The influence of frequency separation on imaging properties in DFEIT
PublikacjaW artykule przedstawiono wpływ wyboru składowych częstotliwościowych dla różnicowej tomografii impedancyjnej na wynik i własności obrazowania w dwuczęstotliwościowej różnicowej tomografii impedancyjnej.A Dual Frequency EIT is an extension of a traditional EIT that uses two sinusoidal signals for imaging. Appropriate selection of signals' frequency allows to achieve reasonable contrast of imaged structure. It has already been shown...
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Texture or Linker? Competitive Patterning of Receptor Assembly toward Ultra-Sensitive Impedimetric Detection of Viral Species at Gold-Nanotextured Titanium Surfaces
PublikacjaIn this work, we study the electrodes with a periodic matrix of gold particles pattered by titanium dimples and modified by 3-mercaptopropionic acid (MPA) followed by CD147 receptor grafting for specific impedimetric detection of SARS-CoV-2 viral spike proteins. The synergistic DFT and MM/MD modeling revealed that MPA adsorption geometries on the Au–Ti surface have preferential and stronger binding patterns through the carboxyl...
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Analysis of bisphenols and their derivatives in infant and toddler ready-to-feed milk and powdered milk by LC MS/MS
PublikacjaReady-to-feed milk and powdered milk packed in different types of packaging lined with resin are chosen as the primary or complementary diet for infants and toddlers. An HPLC–MS/MS method was established and validated for the determination of nineteen bisphenols and their derivatives in such samples. The recoveries were from 31% to 120%, while the values of limit of detection and quantification were in the range of 0.24–0.40 and...
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Effects of thermal history on the performance of low-temperature solid oxide fuel cells with Sm0.2Ce0.8O2-δ electrolyte and LiNi0.81Co0.15Al0.04O2 electrodes
PublikacjaIn this study, low-temperature solid oxide fuel cells with an ∼560 μm thick Sm0.2Ce0.8O2−δ (SDC) electrolyte and ∼890 μm thick LiNi0.81Co0.15Al0.04O2−δ (NCAL) electrodes are constructed and characterized under three experimental conditions. The cell with an NCAL cathode pre-reduced under an H2 atmosphere at 550 °C presents the best electrochemical performance. This is ascribed to facts that the reduction reaction generating Ni–Co...
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Laser-Induced Graphitization of Polydopamine on Titania Nanotubes
PublikacjaSince the discovery of laser-induced graphite/graphene, there has been a notable surge of scientific interest in advancing diverse methodologies for their synthesis and applications. This study focuses on the utilization of a pulsed Nd:YAG laser to achieve graphitization of polydopamine (PDA) deposited on the surface of titania nanotubes. The partial graphitization is corroborated through Raman and XPS spectroscopies and supported...
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Vibrational Quenching of Optically Pumped Carbon Dimer Anions
PublikacjaCareful control of quantum states is a gateway to research in many areas of science such as quantum information, quantum-controlled chemistry, and astrophysical processes. Precise optical control of molecular ions remains a challenge due to the scarcity of suitable level schemes, and direct laser cooling has not yet been achieved for either positive or negative molecular ions. Using a cryogenic wire trap, we show how the internal...
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Scale transformations in model exchange potentials in low energy electron-atom scattering
PublikacjaModel exchange potentials are particularly interesting to account for the indistinguishability between the projectile and target electrons in electron-atom scattering in vacuo and plasma environments. It is well known that their performance is pretty satisfactory in the high energies but also that discrepancies from the results obtained with exact exchange are found toward the zero energy limit. In this article, we examine how...
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Clinical studies of detecting COVID-19 from exhaled breath with electronic nose
PublikacjaThe COVID‑19 pandemic has attracted numerous research studies because of its impact on society and the economy. The pandemic has led to progress in the development of diagnostic methods, utilizing the polymerase chain reaction (PCR) as the gold standard for coronavirus SARS‑CoV‑2 detection. Numerous tests can be used at home within 15 min or so but of with lower accuracy than PCR. There is still a need for point‑of‑care tests available...
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Bioactive hybrid metal-organic framework (MOF)-based nanosensors for optical detection of recombinant SARS-CoV-2 spike antigen
PublikacjaFast, efficient, and accurate detection of SARS-CoV-2 spike antigen is pivotal to control the spread and reduce themortality of COVID-19. Nevertheless, the sensitivity of available nanobiosensors to detect recombinant SARS-CoV-2 spike antigen seems insufficient. As a proof-of-concept, MOF-5/CoNi2S4 is developed as a low-cost, safe, and bioactive hybrid nanostructure via the one-pot high-gravity protocol. Then, the porphyrin, H2TMP,...
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Cavity-expansion approximation for projectile impact and penetration into sand
PublikacjaA one-dimensional problem of a spherical cavity expanding at a constant velocity from zero initial radius in an infinite granular medium, which has the first-kind self-similar solution, is considered. We are solving this dynamic spherical cavity-expansion problem to model rigid spheres penetrating into a granular media. Elastic–plastic deformation of the granular media is described in a barotropic approximation, using the high-pressure...
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The Synergistic Microbiological Effects of Industrial Produced Packaging Polyethylene Films Incorporated with Zinc Nanoparticles
PublikacjaZinc compounds in polyolefin films regulate the transmission of UV-VIS radiation, affect mechanical properties and antimicrobial activity. According to hypothesis, the use of zinc- containing masterbatches in polyethylene films (PE) with different chemical nature—hydrophilic zinc oxide (ZO) and hydrophobic zinc stearate (ZS)—can cause a synergistic effect, especially due to their antimicrobial properties. PE films obtained on an...
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Light-improved glucose sensing on ordered Au-Ti heterostructure
PublikacjaNon-enzymatic electrochemical platforms sensitive towards glucose presence have attracted a worldwide attention during last decades. We report on influence of solar light onto response of gold-titanium heterostructures prepared via controllable approach. The material based on Au nanoparticles orderly distributed over the structured titanium foil was obtained by electrochemical anodization followed by chemical etching, magnetron...
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A Flexible Nafion Coated Enzyme‐free Glucose Sensor Based on Au‐dimpled Ti Structures
PublikacjaThe 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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Detection of the Plant Pathogen Pseudomonas Syringae pv. Lachrymans on Antibody-Modified Gold Electrodes by Electrochemical Impedance Spectroscopy
PublikacjaThe present work describes an impedimetric immunosensor for Pseudomonas syringae pv. lachrymans (Psl) detection. This pathogen infects many crop species causing considerable yield losses, thus fast and cheap detection method is in high demand. In the assay, the gold disc electrode was modified with 4-aminothiophenol (4-ATP), glutaraldehyde (GA), and anti-Psl antibodies, and free-sites were blocked with bovine serum albumin (BSA)....
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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
PublikacjaGlassy 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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Nonlinear free and forced vibrations of a dielectric elastomer-based microcantilever for atomic force microscopy
PublikacjaThe majority of atomic force microcode (AFM) probes work based on piezoelectric actuation. However, some undesirable phenomena such as creep and hysteresis may appear in the piezoelectric actuators that limit their applications. This paper proposes a novel AFM probe based on dielectric elastomer actuators (DEAs). The DE is modeled via the use of a hyperelastic Cosserat model. Size effects and geometric nonlinearity are included...
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Evaluation of mercury content in combustible tobacco products by employing cold vapor atomic absorption spectroscopy and considering the moisture content: a comprehensive study
PublikacjaPlants are mainly made up of water, which constitutes between 80 and 90% of their weight. Moisture factor comes across as one of the most important in tobacco products. Rapid determination of moisture content in tobacco products comes at neces- sity in any tobacco management plants (before and after production). Therefore, the concern has been raised in this study to evaluate the moisture content in four kinds of combustible tobacco...
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Carbon nanowalls: A new versatile graphene based interface for laser desorption/ionization-mass spectrometry detection of small compounds in real samples.
PublikacjaCarbon nanowalls, vertically aligned graphene nanosheets, attract attention owing to their tunable band-gap, high conductivity, high mechanical robustness, high optical absorbance and other remarkable properties. In this paper, we report for the first time, the use of hydrophobic boron-doped carbon nanowalls (CNWs) for laser desorption/ionization of small compounds and their subsequent detection by mass spectrometry (LDI-MS). The...
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Planning the City Against Barriers. Enhancing the Role of Public Spaces
PublikacjaContemporary cities are being fragmented by growing number of technical barriers like roads, railways, infrastructural objects, that generate variety of problems of different nature. The aim of the research is to present the issues connected with such barriers in the city and the ways of solving them. Main problems are e.g.: the destruction of the complexity of urban fabric, functional disadvantages, environmental and landscape...
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Unravelling the role of electron–hole pair spin in exciton dissociation in squaraine-based organic solar cells by magneto-photocurrent measurements
PublikacjaA high absorption coefficient and narrow absorption bands in squaraine (SQ) dyes have resulted in rapidly growing interest in them as a donor material in photovoltaic devices. The exciton dissociation process in organic systems proceeds via a multistep mechanism where the electron–hole pairs (charge transfer states) involved in the current generation process determine the recombination losses and subsequently limit the overall...
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Analysis of metals in air particles from Gdańsk and London with EDX/EDS detectors in electron microscope
PublikacjaElectron microscopy with energy dispersive X-ray spectrometry (EDX/EDS) is the example of non-destructive analytical method for surface elemental analysis, with a potential detection limit of 0.1-0.5 wt.% for most elements. A spatial resolution <10 nm can be achieved using this technique, which provides a basis for the generation of quantitative and qualitative elemental data for individual particles. In order to obtain quantitative...
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Numerical Modeling and Simulation of Vehicular Crashes into Three-Bar Metal Bridge Rail
PublikacjaAdvanced finite element (FE) modeling and simulations were performed on vehicular crashes into a three-bar metal bridge rail (TMBR). The FE models of a sedan, a pickup truck, and a TMBR section were adopted in the crash simulations subject to Manual for Assessing Safety Hardware (MASH) Test Level 2 (TL-2) and Test Level 3 (TL-3) requirements. The test vehicle models were first validated using full-scale physical crash tests conducted...
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Unlocking the electrochemical performance of glassy carbon electrodes by surface engineered, sustainable chitosan membranes
PublikacjaChitosan coatings, derived from crustacean shell waste, possess inherent biocompatibility and biodegradability, rendering them suitable for various biomedical and environmental applications, including electrochemical biosensing. Its amine and hydroxyl functional groups offer abundant sites for chemical modifications to boost the charge transfer kinetics and provide excellent adhesion, enabling the construction of robust electrode-coating...
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Impact of the type of heat exchanger on the characteristics of low-temperature thermoacoustic heat engines
PublikacjaThermoacoustic technologies are considered an effective solution for harnessing low-temperature heat, whether from waste or renewable sources. However, in practice, developing and implementing high-performance ther- moacoustic systems is a complex challenge. In real waste heat recovery systems, heat exchange between ther- moacoustic engines (TAEs) and external heat sources is facilitated by auxiliary systems, such as circulation...
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Injectable biocomposite cement: A dual-setting formula with magnesium potassium phosphate and κ-carrageenan hydrogel for orthopedic advancements
PublikacjaMagnesium phosphate-based cements are highly regarded for their bioactive properties, making them excellent candidates as bone substitutes. Despite their promising attributes, challenges such as high reaction temperature, limited injectability, and brittleness limit their application. This study introduces a dual-setting biocomposite cement, which encompasses both cement hydration and hydrogel's cross-linking. The composition features...
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Spectrophotometric determination of chlorpyrifos in foodstuffs after vortex-assisted surfactant-enhanced emulsification microextraction using magnetic deep eutectic solvents: Analytical greenness profile
PublikacjaIn this work a novel and green vortex-assisted surfactant-enhanced emulsification microextraction (VA-SEEME) based on magnetic deep eutectic solvents (MDESs) was developed for the determination of chlorpyrifos in foodstuffs by UV-Vis spectrophotometric analysis. MDES (trihexyltetradecylphosphonium chloride: MnCl2: octanoic acid) was used as the extractant, non-ionic surfactant Tween-80 was used as an extraction medium, and ethanol...
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UV light-activated gas mixture sensing by ink-printed WS2 layer
PublikacjaWe fabricated a sensing layer from ink-printed WS2 flakes and utilized it for UV-activated gas sensing. The optical imaging of the structure made by repeated printing revealed the continuous layer comprising sub-µm flakes, confirmed independently by small-area AFM images (1×1 µm2). The activity of the sensing surface was investigated locally via AFM scanning of the surface with a polarized probing tip. The results indicated that...
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Compressive and tensile properties of polyurethane foam mimicking trabecular tissue in artificial femoral head bones
PublikacjaThe presented study aimed to examine the compressive and tensile behavior of the polyurethane foams mimicking trabecular tissue in the artificial human femurs and assess their potential to replicate osteoporotic type of human bone tissue. Two types of Synbone femur models: one of the normal density (model 2350) and one of the lower density (model LD2350), and three types of Sawbones femur models (model 1130-21-8, 1130-21-3, 1130-192)...
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The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry
PublikacjaIn this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hy- drocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical chal- lenge to analytical...
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sp2-rich dendrite-like carbon nanowalls as effective electrode for environmental monitoring of explosive nitroaromatic
PublikacjaNitroaromatic compounds are commonly used explosive materials that pose a risk to human health and ecosystems due to their acute toxicity and carcinogenicity. Nitroaromatics have numerous pathways into the environment via discarded munitions (e.g. into the Baltic Sea after World War II), after use in mining operations, and in industrial run-off from factories producing these compounds (which are produced across the world to date)....
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Effect of the ex situ physical and in situ chemical modification of bacterial nanocellulose on mechanical properties in the context of its potential applications in heart valve design
PublikacjaBacterial nanocellulose (BNC) is a promising material for heart valve prostheses. However, its low strength properties limit its applicability in cardiovascular surgery. To overcome these limitations, the mechanical properties of BNC can be improved through modifications. The aim of the research was to investigate the extent to which the mechanical properties of BNC can be altered by modifying its structure during its production...
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Optimization of vortex-assisted supramolecular solvent-based liquid liquid microextraction for the determination of mercury in real water and food samples
PublikacjaA novel method was developed for sample preparation for spectrophotometric determination of Hg(II) in water and food samples. The method was based on vortex-assisted supramolecular solvent-assisted liquid-liquid microextraction (VA-SUPRASs-LLME). Analytical parameters such as pH, chelating agent, solvent type and volume, vortex time and salting out effect were optimized. Surface and normal probability plots were drawn for the variables...
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MnWO4/reduced graphene oxide-based electrochemical sensing platform for simultaneous detection of catechol and resorcinol
Publikacjan this study, a novel electrochemical sensor for accurate and sensitive catechol determination was demonstrated employing a screen-printed graphite electrode (SPGE) modified with MnWO4/reduced graphene oxide (MnWO4/rGO) nanocomposite. The MnWO4/rGO nanocomposite has been successfully prepared by using hydrothermal technique, and it was then characterized using several microscopic and spectroscopic methods (XRD, FE-SEM, and EDS)....
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Optimizing Ni–Cr patterned boron-doped diamond band electrodes: Doping effects on electrochemical efficiency and posaconazole sensing performance
PublikacjaThere is growing interest in developing diamond electrodes with defined geometries such as, for example, micrometer-sized electrode arrays to acquire signals for electroanalysis. For electroanalytical sensing applications, it is essential to achieve precise conductive patterns on the insulating surface. This work provides a novel approach to boron-doped diamond patterning using nichrome masking for selective seeding on an oxidized...
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Head-Space SPME for the Analysis of Organophosphorus Insecticides by Novel Silica IL-Based Fibers in Real Samples
PublikacjaThis work demonstrates the suitability of a newly developed ionic liquid (IL)-based silica SPME fiber for the determination of seven organophosphorus insecticides in cucumber and grapefruit samples by headspace solid-phase microextraction (HS-SPME) with a gas chromatography–flame ionization detector (FID). The sol-gel method released four different sorbent coatings, which were obtained based on a silica matrix containing ILs immobilized...
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Optimum number of actuators to minimize the cross-sectional area of prestressable cable and truss structures
PublikacjaThis paper describes a new computational method for determining the optimum number of actuators to design the optimal and economic cross-sectional area of pin-jointed assemblies based on the conventional force method. The most active members are selected to be prestressed to redistribute stress in the whole structure, resulting in regulating the internal force of bars that face high stress. Reducing stress in critical members allows...
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Seismic performance evaluation of steel buckling-restrained braced frames including SMA materials
PublikacjaThe permanent deformation of the building after seismic excitations can be determined by the Maximum Residual Interstory Drift Ratio (MR-IDR), which may be used for measuring the damage states. Low-post yield stiffness of the steel buckling-restrained braced frame (BRBF) makes this system vulnerable to large MR-IDR after a severe earthquake event. To overcome this issue, this paper investigates the seismic limit state performances...
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N-doped carbon nanospheres as selective fluorescent probes for mercury detection in contaminated aqueous media: chemistry, fluorescence probing, cell line patterning, and liver tissue interaction
PublikacjaA precise nano-scale biosensor was developed here to detect Hg2+ in aqueous media. Nitrogen-doped carbon nanospheres (NCS) created from the pyrolysis of melamine–formaldehyde resin were characterized by FESEM, XRD, Raman spectra, EDS, PL, UV–vis spectra, and N2 adsorption–desorption, and were used as a highly selective and sensitive probe for detecting Hg2+ in aqueous media. The sensitivity of NCS to Hg2+ was evaluated by photoluminescence...
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Tailoring Diffusional Fields in Zwitterion/Dopamine Copolymer Electropolymerized at Carbon Nanowalls for Sensitive Recognition of Neurotransmitters
PublikacjaThe importance of neurotransmitter sensing in the diagnosis and treatment of many psychological illnesses and neurodegenerative diseases is non-negotiable. For electrochemical sensors to become widespread and accurate, a long journey must be undertaken for each device, from understanding the materials at the molecular level to real applications in biological fluids. We report a modification of diamondized boron-doped carbon nanowalls...
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Fragility analysis of structural pounding between adjacent structures arranged in series with various alignment configurations under near‑field earthquakes
PublikacjaA major cause of local to total damages is related to structural pounding in a large number of past earthquakes. In general, these collisions take place as a result of differences in the dynamic characteristics of the colliding structures. To acquire a better perception of the behavior of structures, in this paper, three structures featuring different heights are modeled in series and with various configurations next to each other...
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Pedofilia: istota, rodzaje, zapobieganie. Paedophilia: essence, types, prevention.
PublikacjaPrzedmiotowa monografia opisuje zagadnienie kryminalizacji czynu zabronionego, polegającego na seksualnym wykorzystywaniu nieletnich poniżej piętnastego roku życia – zarówno w aspekcie obecnie obowiązujących rozwiązań, jak i od strony historycznej. Niniejsze opracowanie zwraca uwagę na fakt, iż współczesna typizacja pedofilii w rodzimym porządku normatywnym bierze pod uwagę ujęcie cybernetyczne, gdzie nawiązanie kontaktu pomiędzy...
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Physical and mathematical modelling of implant-fascia system in order to improve laparoscopic repair of ventral hernia
PublikacjaThis paper describes an investigation of biomechanical behaviour of hernia repair, which is focused on the selection of safe linking of certain type of implant with fascia in laparoscopic operation. The strength of various fixations of the implant to the fascia is analysed. Methods: The research is based on experimental observations of operated hernia model behaviour during a dynamic impulse load corresponding to post-operative...