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Wyniki wyszukiwania dla: black phosphorus electrodes
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Defected Ag/Cu-MOF as a modifier of polyethersulfone membranes for enhancing permeability, antifouling properties and heavy metal and dye pollutant removal
PublikacjaIn this study, a novel bimetallic metal-organic framework (MOF) i.e. Ag/Cu-MOF was synthesized using a solvothermal method and later incorporated at different concentrations (0.1–2 wt%) using a phase inversion method for modification and antifouling property improvement of polyethersulfone (PES) membranes. The resulting Ag/Cu-MOF characteristics were investigated using different techniques, such as FTIR, XRD, FE-SEM and EDX. The...
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Seasonal contributions of nutrients from small urban and agricultural watersheds in northern Poland
PublikacjaDiffuse sources of pollution like agricultural or urban runoff are important factors in determining the quality of surface waters, although they are more difficult to monitor thanpointsources.Theobjectiveofourstudywastoverifyassumptionsthattheinflow from agricultural nutrient sources is higher than from urbanized ones. It has been done by comparing the nutrients and organic matter concentrations and loads for three small streams...
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The Simulation of Activated Sludge System for Optimization of Predictive Aeration at Large WWTP
PublikacjaEffective use of biodegradable substrates as an internal carbon sources (ICS) for denitrification and EBPR and predicting performance of aeration systems during nitrification in activated sludge bioreactors, may be useful in realization the sustainable development by potentially saving energy consumption at WWTPs. A large number of WWTPs use activated sludge systems with an integrated removal of carbon, nitrogen and phosphorus...
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MXene-based composites for capacitive deionization – The advantages, progress, and their role in desalination - A review
PublikacjaMXenes, a novel large family of 2D transition metal carbides, carbonitrides and nitrides are currently a “hot topic” in science due to their several fascinating physical and chemical properties. It follows from a rich diversity of their elemental compositions and chemical functionalities. MXenes can form composites with many substances, including polymers or metal oxides, which allows to effective “tune” MXene characteristics to...
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Enhanced Photoelectrocatalytical Performance of Inorganic-Inorganic Hybrid Consisting BiVO4, V2O5, and Cobalt Hexacyanocobaltate as a Perspective Photoanode for Water Splitting
PublikacjaThin layers of BiVO4/V2O5 were prepared on FTO substrates using pulsed laser deposition technique. The method of cobalt hexacyanocobaltate (Cohcc) synthesis on the BiVO4/V2O5 photoanodes consists of cobalt deposition followed by electrochemical oxidation of metallic Co in K3[Co(CN)6] aqueous electrolyte. The modified electrodes were tested as photoanodes for water oxidation under simulated sunlight irradiation. Deposited films...
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Smart Weighing Scale with Feet-Sampled ECG
PublikacjaIn a smart home, health and well-being monitoring systems could be embedded in everyday devices providing a pervasive care. A home bathroom scale is an example of such a device, typically used to measure body weight and very often its composition (e.g. body water/fat percentage). In this paper, we analyzed a potential use of the bathroom scale to measure electrocardiogram (ECG) from electrodes located on the scale's tile. In particular...
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Self-assembly of vertically oriented graphene nanostructures: multivariate characterisation by Minkowski functionals and fractal geometry
PublikacjaThe enormous self-assembly potential that graphene and its derived layered materials offer for responding to the contemporary environmental challenges has made it one of the most investigated materials. Hence, tuning its extraordinary properties and understanding the effect at all scales is crucial to tailoring highly customised electrodes. Vertically oriented graphene nanostructures, also known as carbon nanowalls (CNWs), due...
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Prototype of electrochemical sensor for measurements of volatile organic compounds in gases
PublikacjaThe paper presents a laboratory prototype of an electrochemical sensor for measurements of volatile organic compounds (VOCs) in gases, utilizing ionic liquids and commercial screen printed electrodes by DropSens. The following ionic liquids have been tested as the electrolyte and redox reaction environment: 1-butyl, 3-methylimidazolium dicyanoamide ([BMIM][N(CN)2]), 1-octyl, 3-methylimidazolium tetrafluoroborate ([OMIM][BF4]),...
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Visible light activity of pulsed layer deposited BiVO4/MnO2 films decorated with gold nanoparticles: The evidence for hydroxyl radicals formation
PublikacjaThin films containing BiVO4 and MnO2 deposited on FTO and modified by Au nanoparticles were studied towards their photoelectrochemical and photocatalytical activities in an aqueous electrolyte. Electrodes were prepared by the pulsed laser deposition (PLD) method. The surfactant-free ablation process was used for preparation of the gold nanoparticles (GNP) water suspension. Obtained layers of varied thicknesses (27–115 nm) were...
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Boron-Enhanced Growth of Micron-Scale Carbon-Based Nanowalls: A Route toward High Rates of Electrochemical Biosensing
PublikacjaIn this study, we have demonstrated the fabrication of novel materials called boron-doped carbon nanowalls (B:CNWs), which are characterized by remarkable electrochemical properties such as high standard rate constant (k°), low peak-to-peak separation value (ΔE) for the oxidation and reduction processes of the [Fe(CN)6]3–/4– redox system, and low surface resistivity. The B:CNW samples were deposited by the microwave plasma-assisted...
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Comparison of Classification Methods for EEG Signals of Real and Imaginary Motion
PublikacjaThe classification of EEG signals provides an important element of brain-computer interface (BCI) applications, underlying an efficient interaction between a human and a computer application. The BCI applications can be especially useful for people with disabilities. Numerous experiments aim at recognition of motion intent of left or right hand being useful for locked-in-state or paralyzed subjects in controlling computer applications....
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Noise and Electro-Ultrasonic Spectroscopy of Conducting PolymerThick Films
PublikacjaThick conducting films based on conducting polymer are characterized by DC conductivity and noise in temperature range 10 to 300 K. Conducting polymers could be used e.g. for the top electrode (cathode) in the solid tantalum or niobium capacitors. On the conducting polymer layer the top layer of carbon/graphite and/or silver polymer based pastes is applied in the capacitor technology. Our samples structure consists of conducting...
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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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Improving Accuracy of Contactless Respiratory Rate Estimation by Enhancing Thermal Sequences with Deep Neural Networks
PublikacjaEstimation of vital signs using image processing techniques have already been proved to have a potential for supporting remote medical diagnostics and replacing traditional measurements that usually require special hardware and electrodes placed on a body. In this paper, we further extend studies on contactless Respiratory Rate (RR) estimation from extremely low resolution thermal imagery by enhancing acquired sequences using Deep...
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Interictal high-frequency oscillations in focal human epilepsy
PublikacjaPURPOSE OF REVIEW: Localization of focal epileptic brain is critical for successful epilepsy surgery and focal brain stimulation. Despite significant progress, roughly half of all patients undergoing focal surgical resection, and most patients receiving focal electrical stimulation, are not seizure free. There is intense interest in high-frequency oscillations (HFOs) recorded with intracranial electroencephalography as potential...
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Deposition and Electrical and Structural Properties of La0.6Sr0.4CoO3 Thin Films for Application in High-Temperature Electrochemical Cells
PublikacjaLow-temperature deposition of electroceramic thin films allows the construction of new devices and their integration with existing large-scale fabrication methods. Developing a suitable low-cost deposition method is important to further advance the development of microdevices. In this work, we deposited a 1-lm-thick La0.6Sr0.4CoO3d (LSC) perovskite with high electrical conductivity on sapphire substrates at 400C and analyzed its...
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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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Fluoroaromatic substituents attached to carbon nanotubes help to increase oxygen concentration on biocathode in biosensors and biofuel cells
PublikacjaBased on the known ability of perfluorodecalin/perfluorohydrocarbons to enhance oxygen solubility we modified oxygen sensitive biocathode by adding perfluorinated components to the catholite. This procedure improved the efficiency of the oxygen sensitive cathodes. Glassy carbon electrodes covered with single-wall carbon nanotubes (SWCNTs) with covalently bonded perfluoroaromatic groups were shown to be more sensitive to oxygen,...
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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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Data Compression in Ultrasonic Network Communication via Sparse Signal Processing
PublikacjaThis document presents the approach of using compressed sensing in signal encoding and information transferring within a guided wave sensor network, comprised of specially designed frequency steerable acoustic transducers (FSATs). Wave propagation in a damaged plate was simulated using commercial FEM-based software COMSOL. Guided waves were excited by means of FSATs, characterized by the special shape of its electrodes, and modeled...
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Evolution of the nanostructure of Pt and Pt–Co polymer electrolyte membrane fuel cell electrocatalysts at successive degradation stages probed by X-ray photoemission
PublikacjaWe present a set of XPS (X-ray photoemission spectroscopy) measurements and detailed data-analysis of electrodes for polymer electrolyte membrane fuel cell (PEMFC) based on carbon supported catalysts (Pt and Pt–Co) subjected to a step-like potential cycling (accelerated degradation test). The results of the measurements complete and corroborate parallel TEM (transmission electron microscopy), XRD (X-ray diffraction) and XAS (X-ray...
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Flavones in cocoa defence against Phytophthora megakarya
PublikacjaCross-pollination of suitable genotypes and earlier selection of elite offspring using adequate plants-associated defence markers in plantlets leaves are decisive for development of T. cacao genotypes tolerant to black pods disease (BPD). T. cacao plantlets from manual cross-pollination of ♀SNK64 × ♂UPA143 were analyzed for their susceptibility to BPD using leaf disc test. Subsequently, leaves (healthy, wounded and wound+infected)...
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Reemission of inorganic pollution from permafrost? A freshwater hydrochemistry study in the lower Kolyma basin (North-East Siberia)
PublikacjaPermafrost regions are under particular pressure from climate change resulting in widespread landscape changes, which impact also freshwater chemistry. We investi- gated a snapshot of hydrochemistry in various freshwater environments in the lower Kolyma river basin (North-East Siberia, continuous permafrost zone) to explore the mobility of metals, metalloids and non-metals resulting from permafrost thaw. Partic- ular attention...
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Insights into the microbial community of treated wastewater, its year-round variability and impact on the receiver, using cultivation, microscopy and amplicon-based methods
PublikacjaApart from chemical constituents, wastewater treatment plant (WWTP) effluents also release microorganisms that can be important to the receiving water bodies either from a sanitary point of view, or taking to the account the biogeochemical potential of the recipients. However, little is known about the treated wastewater microbial community, its composition, seasonal changes, functions and fate in the waters of the receiver. Thus,...
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Evaluation of the use of reindeer droppings for monitoring essential and non-essential elements in the polar terrestrial environment
PublikacjaExcess or toxic metals, non-metals and metalloids can be eliminated from the organism by deposition in inert tissue (e.g. fur) or excretion with body secretions, urine and faeces. Droppings are one of the main routes for the elimination of multiple elements and they can be collected without direct contact with the animal. Contaminant concentration has been examined in non-lethally collected tissues of several species (especially...
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Development and Assessment of Regeneration Methods for Peptide-Based QCM Biosensors in VOCs Analysis Applications
PublikacjaCleaning a quartz crystal microbalance (QCM) plays a crucial role in the regeneration of its biosensors for reuse. Imprecise removal of a receptor layer from a transducer’s surface can lead to unsteady operation during measurements. This article compares three approaches to regeneration of the piezoelectric transducers using the electrochemical, oxygen plasma and Piranha solution methods. Optimization of the cleaning method allowed...
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Enhanced susceptibility of SARS-CoV-2 spike RBD protein assay targeted by cellular receptors ACE2 and CD147: Multivariate data analysis of multisine impedimetric response
PublikacjaSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters the cells through the binding of spike protein to the host cell surface-expressing angiotensin-converting enzyme 2 (ACE2) or by endocytosis mediated by extracellular matrix metalloproteinase inducer (CD147). We present extended statistical studies of the multisine dynamic electrochemical impedance spectroscopy (DEIS) revealing interactions between Spike RBD and...
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Cathodic Protection System of the Spiral Classifier at the KGHM Polska Miedź S.A. Ore Concentration Plant—Case Study of Commissioning and Control of Operating Parameters
PublikacjaThe project involved designing, constructing and commissioning a cathodic protection system for a selected spiral classifier operating at the KGHM Polska Miedź S.A. Ore Concentration Plant (O/ZWR). The authors developed a concept and assumptions regarding the corrosion protection of a large industrial device using a cathodic protection system with an external power source. Pre-project studies included conducting a trial polarization...
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Expert System and Decision Support System for Electrocardiogram Interpretation and Diagnosis: Review, Challenges and Research Directions
PublikacjaElectrocardiography (ECG) is one of the most widely used recordings in clinical medicine. ECG deals with the recording of electrical activity that is generated by the heart through the surface of the body. The electrical activity generated by the heart is measured using electrodes that are attached to the body surface. The use of ECG in the diagnosis and management of cardiovascular disease (CVD) has been in existence for over...
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Human verbal memory encoding is hierarchically distributed in a continuous processing stream
PublikacjaProcessing of memory is supported by coordinated activity in a network of sensory, association, and motor brain regions. It remains a major challenge to determine where memory is encoded for later retrieval. Here we used direct intracranial brain recordings from epilepsy patients performing free recall tasks to determine the temporal pattern and anatomical distribution of verbal memory encoding across the entire human cortex. High...
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Formaldehyde detection with chemical gas sensors based on WO3 nanowires decorated with metal nanoparticles under dark conditions and UV light irradiation
PublikacjaWe report results of formaldehyde gas (CH2O) detection under dark conditions and UV light irradiation with pristine tungsten trioxide nanowires (WO3 NWs) and metal nanoparticles decorated WO3 NWs gas sensing layers. The resistive layers were deposited by one step aerosol assisted chemical vapor deposition (AACVD) on commercial alumina substrates with 10-pair interdigitated platinum electrodes. The elaborated gas sensors, based...
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Direct electrical stimulation of the human brain has inverse effects on the theta and gamma neural activities
PublikacjaObjective: Our goal was to analyze the electrophysiological response to direct electrical stimulation (DES) systematically applied at a wide range of parameters and anatomical sites, with particular focus on neural activities associated with memory and cognition. Methods: We used a large set of intracranial EEG (iEEG) recordings with DES from 45 subjects with electrodes...
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Combined effect of nitrogen-doped functional groups and porosity of porous carbons on electrochemical performance of supercapacitors
PublikacjaIn this work, nitrogen-doped porous carbons obtained from chitosan, gelatine, and green algae were investigated in their role as supercapacitor electrodes. The effects of three factors on electrochemical performance have been studied— of the specific surface area, functional groups, and a porous structure. Varying nitrogen contents (from 5.46 to 10.08 wt.%) and specific surface areas (from 532 to 1095 m2g−1) were obtained by modifying...
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Formation of Highly Conductive Boron-Doped Diamond on TiO2 Nanotubes Composite for Supercapacitor or Energy Storage Devices
PublikacjaIn the present paper, we report the phenomena of the formation of the novel composite nanostructures based on TiO2 nanotubes (NTs) over-grown by thin boron-doped diamond (BDD) film produced in Microwave Plasma Enhanced Chemical Vapor Deposition (PE MWCVD). The TiO2 nanotube array overgrown by boron-doped diamond immersed in 0.1 M NaNO3 can deliver high specific capacitance of 7.46 mF cm−2. The composite electrodes were characterized...
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Status report on high temperature fuel cells in Poland – Recent advances and achievements
PublikacjaThe paper presents recent advances in Poland in the field of high temperature fuel cells. The achievements in the materials development, manufacturing of advanced cells, new fabrication techniques, modified electrodes and electrolytes and applications are presented. The work of the Polish teams active in the field of solid oxide fuel cells (SOFC) and molten carbonate fuel cell (MCFC) is presented and discussed. The review is oriented...
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Titania nanotubes modified by a pyrolyzed metal-organic framework with zero valent iron centers as a photoanode with enhanced photoelectrochemical, photocatalytical activity and high capacitance
PublikacjaThe paper discusses the synthesis, photoelectrochemical and electrochemical behaviour of titania nanotube arrays modified by a pyrolyzed metal-organic framework (MOF). A poly(3,4–ethylenedioxyphene) (PEDOT) matrix with an embedded inorganic network of iron hexacyanoferrate (BP) covering TiO2 nanotubes (TNT) is used as a MOF for the further sintering procedure, resulting in a novel, thin film of carbonaceous wrap supported Fe catalytic...
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Organic-inorganic composites consisted of poly(3,4-ethylenedioxythiophene)and Prussian Blue analogues
PublikacjaThe organic-inorganic material consisted of poly(3,4-ethylenedioxythiophene) (pEDOT) and copper hexacyanoferrate (Cuhcf) was synthesized. The pEDOT film with Fe(CN)63−/4− as counter-ions potentiodynamically polarized in aqueous CuCl2 electrolyte brings about stable hybrid material (pEDOT/Cuhcf) performing single redox activity of FeII/III at a formal potential Ef = 0.61 V (vs. Ag/AgCl/0.1 M KCl) and less clearly shaped two redox...
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Preparation and structure of nanocrystalline sol-gel derived Cu doped LiTi2O4 powders
PublikacjaAmong the spinel oxides materials, lithium titanate (Li1+xTi2-xO4 where 0 ≤ x ≤ 0.33) could be very interested from pratical applications point of view. Lithium titanate is a II type spinel oxide superconductor with relatively high (~13 K for x = 0) superconducting transition temperature Tc. Above Tc lithium titanate shows metallic behaviour and can be used e.g. as electrodes for rechargeable lithium-ion batteries. Since the discovery...
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A Closed Bipolar Electrochemical Cell for the Interrogation of BDD Single Particles: Electrochemical Advanced Oxidation
PublikacjaA closed bipolar electrochemical cell containing two conductive boron-doped diamond (BDD) particles of size 250 – 350 m, produced by high-pressure high-temperature (HPHT) synthesis, has been used to demonstrate the applicability of single BDD particles for electrochemical oxidative degradation of the dye, methylene blue (MB). The cell is fabricated using stereolithography 3D printing and the BDD particles are located at either...
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Reaktory elektrochemiczne w przemyśle - konstrukcja i zastosowania
PublikacjaZ biegiem lat reakcje elektrochemiczne przestały być postrzegane jedynie jako eksperymenty laboratoryjne lub proste baterie. Chociaż mechanizm reakcji i budowa prostych reaktorów znana jest ludzkości już od ponad 100 lat w ostatnich latach można zauważyć największy wzrost zainteresowania tą dziedziną. Nowy stale opracowywane są lepsze projekty budowy reaktorów. Modyfikacje to nie tylko rodzaje i formy materiałów, z których wykonane...
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Use of a wastewater recovery product (struvite) to enhance subtropical seagrass restoration
PublikacjaSeagrasses are in decline worldwide, and their restoration is relatively expensive and unsuccessful compared to other coastal systems. Fertilization can improve seagrass growth in restoration but can also release nutrients and pollute the surrounding ecosystem. A slow-release fertilizer may reduce excessive nutrient discharge while still providing resources to the seagrass's rhizosphere. In this study, struvite (magnesium ammonium...
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Macro-nutrients recovery from liquid waste as a sustainable resource for production of recovered mineral fertilizer: Uncovering alternative options to sustain global food security cost-effectively
PublikacjaGlobal food security, which has emerged as one of the sustainability challenges, impacts every country. As food cannot be generated without involving nutrients, research has intensified recently to recover unused nutrients from waste streams. As a finite resource, phosphorus (P) is largely wasted. This work critically reviews the technical applicability of various water technologies to recover macro-nutrients such as P, N, and...
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Potentiometric sensor with lipid-polymer membranes for quality assessment of French red wines
PublikacjaThe quality of wines resulting from vineyard management is important for consumers due to the taste and price of wines. In this work, the quality of red wines of three vintages has been investigated by potentiometric sensors with six all-solid-state electrodes. Two series of experiments were carried out. The first involved a qualitative analysis of wine of different vintages from freshly opened bottles. The second consisted of...
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A facile strategy for reclaiming discarded graphite and harnessing the rate capabilities of graphite anodes
PublikacjaGraphite negative electrodes are unbeaten hitherto in lithium-ion batteries (LiBs) due to their unique chemical and physical properties. Thus, the increasing scarcity of graphite resources makes smart recycling or repurposing of discarded graphite particularly imperative. However, the current recycling techniques still need to be improved upon with urgency. Herein a facile and efficient hydrometallurgical process is reported to...
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Enhanced Charge Storage Mechanism And Long-Term Cycling Stability In Diamondized Titania Nanocomposite Supercapacitors Operating In Aqueous Electrolytes
PublikacjaThe long cycle life stability jointly with high energy density are limiting broader feasible applications of supercapacitors. The novel diamondized titania nanocomposite supercapacitors deliver high power and energy densities along with high capacitance retention rates. Supercapacitor electrodes were fabricated utilizing a combination of Ti anodization followed by chemical vapor deposition resulting in simultaneous growth of complex...
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Potentiometric Solid-Contact Ion-Selective Electrode for Determination of Thiocyanate in Human Saliva
PublikacjaA new solid-contact potentiometric ion-selective electrode for the determination of SCN− (SCN-ISE) has been described. Synthesized phosphonium derivative of calix[4]arene was used as a charged ionophore. The research included selection of the ion-selective membrane composition, determination of the ISEs metrological parameters and SCN-ISE application for thiocyanate determination in human saliva. Preparation of the ISEs included...
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Enhanced photoelectrochemical and photocatalytic performance of iodine-doped titania nanotube arrays
PublikacjaThe paper discusses the synthesis and performance of iodine doped titania nanotube arrays exhibited under irradiation. The doping procedure was performed as an additional, electrochemical process carried out after formation of nanotube arrays via anodization of Ti substrate. The optical and structural properties were characterized using Raman, UV-vis, photoluminescence and X-ray photoelectron spectroscopy. The surface morphology...
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Synthesis, characterization, and interactions of single-walled carbon nanotubes modified with doxorubicin with Langmuir–Blodgett biomimetic membranes
PublikacjaThe synthesis, characterization, and the influence of single-walled carbon nanotubes (SWCNTs) modified with an anticancer drug doxorubicin (DOx) on the properties of model biological membrane as well as the comparison of the two modes of modification has been presented. The drug was covalently attached to the nanotubes either preferentially on the sides or at the ends of the nanotubes by the formation of hydrazone bond. The efficiency...
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Rubber wastes recycling for developing advanced polymer composites: A warm handshake with sustainability
PublikacjaRecycling and management of rubber wastes experiences an early-stage maturity in the quest for sustainable and circular materials. Up to now, solutions proposed for sustainable development of rubber wastes are limited, so that properties and performance features of recycled products are inadequate for practical applications. Herein, an experimental protocol is introduced for manufacturing semi-sustainable polymer composites based...
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Rapid and simple multi-analyte LC–MS/MS method for the determination of benzodiazepines and Z-hypnotic drugs in blood samples: Development, validation and application based on three years of toxicological analyses
PublikacjaBenzodiazepines (BZDs) and Z-drugs have been particularly important treatments for sleeping and anxiety disorders for many years. However, recently, a number of new benzodiazepines (named designer benzodiazepines, DBZDs) were synthesised, but some of them have never been used in the clinic; they reached the black drug market as new psychoactive substances and are used for recreational purposes. The abuse of these substances has...