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The effects of the IM1-12Br ionic liquid and the oxytetracycline mixture on selected marine and brackish microorganisms
PublicationThe number of applications and commercialized processes utilizing ionic liquids has been increasing, and it is anticipated that this trend will persist and even intensify in the future. Ionic liquids possess desirable characteristics, such as low vapor pressure, good water solubility, amphiphilicity, and stability. Nevertheless, these properties can influence their environmental behavior, resulting in resistance to biotic and abiotic...
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Evidence of mutations conferring resistance to clarithromycin in wastewater and activated sludge
PublicationThe occurrence of clarithromycin in wastewater samples and of the activated sludge bacteria possibly resistant to this pharmaceutical was the object of the study. Samples of wastewater or activated sludge were taken from a municipal wastewater treatment plant in summer and winter and characterised regarding their clarithromycin concentrations and the presence of nucleic acid fragments (Cla-sequences) known to be responsible for...
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Exploring Mechanism of Corrosion Inhibition of WE43 and AZ31 Alloys by Aqueous Molybdate in Hank’s Solution by Multisine Impedimetric Monitoring
PublicationThe concept of utilizing multisine dynamic electrochemical impedance spectroscopy to monitor effectiveness of a model molybdate inhibitor for AZ31 and WE43 Mg alloys is proposed. The corrosion kinetics and instantaneous values of inhibition efficiency (IE) of molybdate at concentrations up to 150 mM were examined. The inhibitor provides inhibition in Hank’s solution at concentrations starting from ca. 25 mM, with the IE of about...
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Sessile droplet contact angle of water–Al2O3, water–TiO2 and water–Cu nanofluids
PublicationThis work presents measurements of the contact angle of sessile droplets for three nanofluids, i.e. water–Al2O3, water–TiO2 and water–Cu. The plates made of glass, anodized aluminium and stainless steel of different roughness served as substrates. Ultrasonic vibration was used for 30–60 min in order to stabilise the dispersion of the nanoparticles. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight....
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Joint experimental and theoretical study on electron scattering from titanium tetrachloride (TiCl4) molecule
PublicationAbsolute grand-total cross section for electron scattering from titanium tetrachloride, TiCl4, molecule was measured at electron-impact energies ranging from 0.3 to 300 eV, in the linear electron-transmission experiment. The elastic integral, differential, momentum transfer, and total ionization cross sections for TiCl4 molecule were also calculated for low and intermediate collisional energies at the level of various theories. The...
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3D Metamaterial Ultra-Wideband Absorber for curved surface
PublicationThis paper proposes a three-dimensional metamaterial absorber based on a resistive film patch array to develop a low-cost, lightweight absorber for curved surfaces. An excellent absorption over a large frequency band is achieved through two different yet controllable mechanisms; In the first mechanism, a considerable attenuation in the wave power is achieved via graphite resistive films. The absorption is then intensified through...
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Partitioning of heavy metals in sub-surface flow treatment wetlands receiving high-strength wastewater
PublicationThe retention of heavy metals at two pilot-scale treatment wetlands (TWs), consisting of two vertical flow beds (VSSF) followed by a horizontal flow bed (HSSF) was studied. The TWs received highstrength wastewater: reject waters from sewage sludge centrifugation (RW) and landfill leachate (LL). The concentrations of metals: Fe, Mn, Zn, Al, Pb, Cu, Cd, Co, Ni were measured in treated wastewater, substrate of the beds and in plant...
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Sustainable recovery of plant essential Nitrogen and Phosphorus from human urine using industrial coal fly ash
PublicationCoal-based thermal power plants play a pivotal role in meeting global energy demand. The amount of fly ash generated from these plants increases every year, and its successful use has posed a significant environmental risk in the last decade. In this study, coal fly ash was packed in a fixed-bed adsorption column to remove Urea–N from synthetic human urine. To assess the efficacy of fly ash in the removal of Nitrogen, various process...
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PRELIMINARY RESULTS FROM APPLICATION PHOSLOCK® TO REMOVE PHOSPHORUS COMPOUNDS FROM WASTEWATER
PublicationThe aim of the study is to assess the removal effectiveness of phosphorus compoundsby using lanthanum-modified bentonite. This material was produced by the Australian company Phoslock® Water Solutions Pty Ltd. According to the company, Phoslock® has substantial capacity to bound phosphate anions. The investigation was carried out in steady conditions in laboratory model with beakers. The results of the study are related to the...
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Distribution of volatile organohalogen compounds in petrochemical plant water streams
PublicationThe study assesses halogenated volatile organic compound concentrations in the water and wastewaterstreams of a petrochemical plant. Water samples were collected at 11 sampling points during 5 samplingcampaigns. The samples were collected from the oil dewaxing unit and in the wastewater treatmentplant. Dichloromethane and 1,2-dichloroethane were the most frequently determined compounds. Tetrachloroethenewas also detected at the...
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Ultrasound-assisted deep eutectic solvent-based liquid–liquid microextraction for simultaneous determination of Ni (II) and Zn (II) in food samples
PublicationA new approach was developed for the simultaneous pre-concentration and determination of Ni (II) and Zn (II) in food samples. This method is based on ultrasound-assisted liquid–liquid micro extraction using hydrophobic deep eutectic solvent (DES) and 1,10-phenanthroline as chelating agent. The effect of several parameters, such as pH, selection and volume of DES, amount of chelating agent, time of sonication and centrifugation,...
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The SARS‐CoV ‐2 specific IgG antibodies biophotonic sensor
PublicationIn this paper, we present the design and the principle of operation of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) specific immunoglobulin G (IgG) biophotonic sensor, which is based on the single-mode telecommunication fiber. We fabricated the sensor head at the face of the single mode fiber-28. Due to the process of bio-functionalization, our sensor has the ability to selectively detect the SARS-CoV-2 specific...
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Impact of Volcanic Eruptions on the Occurrence of PAHs Compounds in the Aquatic Ecosystem of the Southern Part of West Spitsbergen (Hornsund Fjord, Svalbard)
PublicationThe paper presents changes in concentration levels of dioxin-like compounds that can be observed over the course of four study seasons in water samples collected from the Arctic watershed of Svalbard. The conducted analysis involved anthropogenic and natural factors that may affect the concentration of PAHs in the study samples of water. An attempt is made to indicate the emission source of the compounds being deposited and to...
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Application of Electronic Nose to Ambient Air Quality Evaluation With Respect to Odour Nuisance in Vicinity of Municipal Landfills and Sewage Treatment
PublicationThis chapter contains information about application of the electronic nose type instruments to evaluation of ambient air odour quality connected with such sectors of human activity as municipal landfills or sewage treatment plants. The authors present potential sources of emission from these sectors, characterize the chemical compounds responsible for presence of unpleasant odours, describe the influence of those compounds on human...
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Complementary Use of Multi-dimensional Gas Chromatography and Proton Transfer Reaction Mass Spectrometry for Identification of Rapeseed Oil Quality Indicators
PublicationThe change of concentration of various volatiles generated during frying may be an indicator of oil quality. Chemical compounds such as aldehydes, ketones, alcohols and carboxyl acids are the products of oxidation during thermal degradation of edible oils. Shown in this work is a complementary use of GC×GC-TOFMS and PTR-MS for the detection and determination of quality indicators of rapeseed oil. The former technique was used for...
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Deep eutectic solvents based assay for extraction and determination of zinc in fish and eel samples using FAAS
PublicationA new assay based on effective (high recovery) extraction by means of deep eutectic solvents (DESs) was developed for ppb level determination of zinc in fishes and eel samples. Choline chloride and Phenol in a 1:2 M ratio was selected as optimal DES-based extraction solvent. 8-Hydroxy quinoline was used as a chelating agent for zinc ions. The optimized conditions were found at pH value of 8, ligand concentration of 10 mg/L, THF...
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Environmental degradation of Ti alloys in artificial saliva and a role of fluorides
PublicationThe titanium and its alloys are potentially prone to hydrogen embrittlement, including those proposed for dental implants. The research has been aimed to assess a susceptibility to environment-enhanced degradation of the Ti-13Zr-13Nb alloy in artificial saliva with or without hydrofluoric acid, subject or not to cathodic polarisation. The results have shown that even if artificial saliva is safe environment, both cathodic polarization...
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Environmental degradation of titanium alloy in artificial saliva
PublicationThe titanium and its alloys are potentially prone to hydrogen embrittlement, including those proposed for dental implants. The research has been aimed to assess a susceptibility to environment-enhanced degradation of the Ti-13Zr-13Nb alloy in artificial saliva with or without hydrofluoric acid, subject or not to cathodic polarisation. The results have shown that even if artificial saliva is safe environment, both cathodic polarization...
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Interferometric Sensor of Wavelength Detuning Using a Liquid Crystalline Polymer Waveplate
PublicationOperation of a polarization interferometer for measurement of the wavelength changes of a tunable semiconductor laser was investigated. A lambda/8 waveplate made from liquid crystalline polymer is placed in one of interferometers’ arms in order to generate two output signals in quadrature. Wavelength was measured with resolution of 2 pm in the wavelength range 628–635 nm. Drift of the interferometer, measured in the period of 500...
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Instantaneous impedance monitoring of AA 7075 aluminum alloy corrosion in borate buffer with admixed chloride ions
PublicationThe study presents a research capabilities of Dynamic Electrochemical Impedance Spectroscopy (DEIS) as a tool used for instantaneous on-line monitoring of corrosion processes on the example of AA 7075 aluminum alloy. A borate buffer with admixed chloride ions in a quantity ranging from 0.05 to 25 mM was used to represent different types of corrosion attack. The surface of samples specimens was evaluated before and after the tests...
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High-Resolution, Broad-Range Detection Setup for Polarimetric Optical Fiber Sensors
PublicationA common-path polarization interferometer using a Wollaston prism and an area detector for the measurement of retardation or optical path difference is presented. Employing a moderate-resolution 1280 by 1024 pixel monochrome camera, it offers a measurement range of approximately 780 radians at 830 nm and 1350 radians at 515 nm while maintaining a high measurement resolution. Retardation introduced by a zero-order waveplate or a...
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Assessment of metal removal in a surface flow constructed wetland treating landfill leachate
PublicationThe study concerns heavy metal retention and transformation processes in a free water surface constructed wetland treating landfill leachate in a temperate climate. The total effectiveness of heavy metals removal in the analyzed CW was evaluated basing on heavy metals inflow and outflow concentrations. The concentrations of eight heavy metals (Fe, Mn, Zn, Pb, Ni, Cu, Cr, Cd) in landfill leachate (LL) and sediments were measured....
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SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART II. QUATERNARY AMMONIUM COMPOUNDS
PublicationThe paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative...
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Study of the formation of calcareous deposits on cathodically protected steel in Baltic sea water
PublicationPurpose – The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water. Design/methodology/approach – Steel electrodes were cathodically polarized in natural Baltic sea water at potential þ0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode’s surface...
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Multisine impedimetric probing of biocatalytic reactions for label-free detection of DEFB1 gene: How to verify that your dog is not human?
PublicationAlbert is a dog (Canis familiaris), but he does not realize this. Albert loves human food (and beer), watching movies on the internet, sleeping in bed, and more. But he should not do all these things. To convince him that, we have desinged a test procedure. The DEFB1 gene is unique to human species. Detecting its presence from saliva and in short periods may offer an advantage in the field of forensic medicine, and influence Albert’s...
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An investigation of microstructural basis for corrosion behavior of Al-CNT composites fabricated by SPS
PublicationIn this research effect of the addition of multi-wall carbon nanotubes (MWCNTs) as additive powder on microstructure and corrosion behavior of fabricated Al-CNT composites was studied. The aluminum powder and CNTs were mixed with high energy planetary ball-mill. It is observed that by increasing milling time, the uniformity of CNTs on aluminum matrix and consequently corrosion resistance of Al-CNT composite is increased. On the...
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AUTOMATED SYSTEM FOR FLUCTUATION ENHANCED GAS SENSING
PublicationResistance gas sensors exhibit random phenomena (resistance noise) which can be utilized to improve gas sensitivity and selectivity. That new emerging technique has to be investigated to recognize optimal parameters for gas detection. It means that a measurement system has to have ability of numerous parameters adjustment (e.g., sampling frequency, heater voltage, polarization current, voltage noise amplification). That fact induced...
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Distribution and bioavailability of mercury in the surface sediments of the Baltic Sea
PublicationThe study aimed to determine the level of mercury (Hg) and its labile and stable forms in the surface sediments of the Baltic Sea. The work considers the impact of current and historical sources of Hg on sediment pollution, together with the influence of different environmental parameters, including water inflows from the North Sea. Surface sediments (top 5 cm) were collected in 2016–2017 at 91 stations located in different...
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Expression of cyclin D1 after treatment with doxorubicin in the HL-60 cell line
PublicationIncreased levels of cyclin D1 and amplification of CCND1 gene occur in many types of cancers. We have followed the expression of cyclin D1 after treatment with doxorubicin with reference to cell death and other possible therapeutic implications. The effect of the treatment on the cell cycle, survival, intracellular level (flow cytometry), and intracellular localization of cyclin D1 (fluorescence microscopy) and expression of...
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Natural Deep Eutectic Solvents as Agents for Improving Solubility, Stability and Delivery of Curcumin
PublicationPurpose Study on curcumin dissolved in natural deep eutectic solvents (NADES) was aimed at exploiting their beneficial properties as drug carriers. Methods The concentration of dissolved curcumin in NADES was measured. Simulated gastrointestinal fluids were used to determine the concentration of curcumin and quantum chemistry computations were performed for clarifying the origin of curcumin solubility enhancement in NADES. Results NADES...
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Monitoring of lysozyme thermal denaturation by volumetric measurements and nanoDSF technique in the presence of N-butylurea
PublicationThe results of thermal studies of denaturation of hen egg white lysozyme (HEWL) in water and an aqueous solution of N-butylurea (BU) are presented. High-precision densimetric measurements were used to characterize and analyze the changes of the specific volume, v, during temperature elevation. The temperature of the midpoint of protein denaturation was also determined by nanoDSF technique (differential scanning fluorimetry). The...
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Rheology of potato starch chemically modified with microwave-assisted reactions
PublicationNative potato starch was sulfated, selenated, borated, silicated and zincatated by means of microwave-assisted reactions with varying doses of relevant reagents. Resulting products were characterized involving rheological behavior of pastes, their weight-average molecular weight (Mw), and radius of gyration (Rg). Most of the pastes showed shear-thinning behavior, with the flow behavior index (n) below unity. The pastes of starch...
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Human serum interactions with phenolic and aroma substances of Kaffir(Citrus hystrix) and Key lime (Citrus aurantifolia) juices
PublicationTo understand the therapeutic application of polyphenols extracted from Kaffir (PolKaf) and Key (PolKey) limesdifferent analytical methods were applied. Based on quantitative analysis by two dimensional gas chromato-graphy (GC×GC) and time of flight mass spectrometry (TOFMS) it can be observed that the biggest differencesin the contents of selected terpenes of Kaffir and Key limes occur in chemical compounds such as limonene, citraland...
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Hybrid metal and non-metal activation of Oxone by magnetite nanostructures co-immobilized with nano-carbon black to degrade tetracycline: Fenton and electrochemical enhancement with bio-assay
PublicationElectrochemically synthesized magnetite nanostructures (ESMNPs) as a metal activator and nano-carbon black (NCB) as a non-metal activator were co-immobilized by alginate natural polymer to activate Oxone for the degradation of tetracycline (TC) antibiotic. The formation of sulfate radical was indirectly confirmed during the Oxone/ESMNPs/NCB/alginate process via the addition of scavenging compounds. This study revealed the high...
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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
PublicationIn 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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Reply to Comment on ‘Nanodiamond incorporated human liver mimicking phantoms: prospective calibration medium of magnetic resonance imaging’
PublicationDependence of the spin–lattice (T1) relaxation times on the nanodiamond concentration in human liver phantoms is discussed. Factors affecting stability and and reproducibility of these phantoms are presented. The need for comparative measurements on multiple MRI scanners for better understanding of potential variations in the obtained imaging data is emphasised.
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Interspecific and intraspecific variation in organochlorine pesticides and polychlorinated biphenyls using non-destructive samples from Pygoscelis penguins
PublicationAs humans are present in Antarctica only for scientific and tourism-related purposes, it is often described as a pristine region. However, studies have identified measurable levels of Persistent Organic Pollutants (POPs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the Antarctic region. These are highly toxic anthropogenic compounds with tendency to travel long distances and reach remote environments, where...
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Flexoelectricity and apparent piezoelectricity of a pantographic micro-bar
PublicationWe discuss a homogenized model of a pantographic bar considering flexoelectricity. A pantographic bar consists of relatively stiff small bars connected by small soft flexoelectric pivots. As a result, an elongation of the bar relates almost to the torsion of pivots. Taking into account their flexoelectric properties we find the corresponding electric polarization. As a results, the homogenized pantographic bar demonstrates piezoelectric...
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Diamond-Phase (Sp3-C) Rich Boron-Doped Carbon Nanowalls (Sp2-C): A Physico-Chemical And Electrochemical Properties
PublicationThe growth of B-CNW with different boron doping levels controlled by the [B]/[C] ratio in plasma, and the influence of boron on the obtained material’s structure, surface morphology, electrical properties and electrochemical parameters, such as -ΔE and k°, were investigated. The fabricated boron-doped carbon nanowalls exhibit activity towards ferricyanide redox couple, reaching the peak separation value of only 85 mV. The flatband...
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Precipitation of calcium carbonate in the presence of rhamnolipids in alginate hydrogels as a model of biomineralization
PublicationThis paper reports the effects of rhamnolipids presence in the alginate hydrogel and CO32- solution, on the precipitation of CaCO3 in the Ca2+ loaded alginate hydrogel. Characteristics of the formed particles are discussed. Model conditions containing alginate hydrogel and rhamnolipids were used in order to mimic the natural environment of biomineralization in biofilms. It has been shown that rhamnolipids affect the characteristics...
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Rating mathematical models for first-pass of tracer in pCT lung studies
PublicationThis paper presents a comparison of model based on the Gauss function and the most commonly used Gamma-variate model in perfusion computed tomography (pCT) lung studies. It also verifies whether used model affects value of blood volume parameter. Three mean concentration-time curves were created from actual pCT measurements: arterial input function, blood vessels in lungs and lung parenchyma. On the basis of these mean curves we...
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Comparison of bacterial production in the water column between two Arctic fjords, Hornsund and Kongsfjorden (West Spitsbergen)
PublicationBacterial production and the accompanying environmental factors were measured in the water columns of two Arctic fjords during the cruise in July and August 2013. Water samples were collected at six stations located in the central part of Hornsund and Kongsfjorden. In Hornsund, where average water temperatures were 1.25-fold lower than in Kongsfjorden, the bacterial production was twice as high (0.116 ± 0.102 vs 0.05 ± 0.03 mg...
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Method of selecting the LS-SVM algorithm parameters in gas detection process
PublicationIn this paper we showed the method of resistive gas sensors data processing. The UV irradiation and temperature modulation was applied to improve gas sensors’ selectivity and sensitivity. Noise voltage across the sensor’s terminals (proportional to its resistance fluctuations) was recorded to estimate power spectral density. This function was an input data vector for LS-SVM (least squares – support vector machine) algorithm, which...
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Removal efficiency of phenol by ozonation process with calcium peroxide from aqueous solutions
PublicationPhenol has been introduced as a priority pollutant by the US Environmental Protection Agency. Advanced oxidation processes (AOPs) are one of the most efcient methods for removal of non-degradable organic pollutants in aqueous solutions. The removal efciencies of phenol and COD under optimal conditions pH=3, phenol concentration=5 mg/L, CaO2 concentration=0.025 mg/L, temperature 25 °C, 1 g/min ozonation rate and contact time=90...
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Is sequential batch reactor an efficient technology to protect recipient against non-steroidal anti-inflammatory drugs and paracetamol in treated wastewater?
PublicationThe tested facility was a wastewater treatment plant (WWTP) in Swarzewo, where the wastewater treatment takes place in aeration chambers with activated sludge using sequential batch reactors (SBRs). The concentration of the following pharmaceuticals: ibuprofen, paracetamol, flurbiprofen, naproxen, diclofenac, and its metabolites 5OH-diclofenac and 4OH-diclofenac was tested in influents and effluents. Simultaneously, the conventional...
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Degradation of bisphenol S – a contaminant of emerging concern - by synergistic ozone and percarbonate based AOP
PublicationDegradation of bisphenol S was studied using ozone activated by sodium percarbonate and the effectiveness of optimized process was compared with the peroxone process. The influence of several factors including sodium percarbonate concentration, ozone dose, pH, and water matrix were investigated. A synergetic coefficient of 3.84 was achieved for the combination of sodium percarbonate and ozone, confirming the effectiveness of this...
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Label‐free optical detection of cyclosporine in biological fluids
PublicationIn this paper, a spectroscopic method for determination of cyclosporine concentrations in biological fluids is presented. Blood plasma and hemoglobin solutions are chosen for the experiment. For various cyclosporine concentrations in blood plasma and hemoglobin, absorbance measurements in spectra range from 600 to 1100 nm are performed. The measurement results are analyzed by the use of a dedicated algorithm. The obtained data...
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Monitoring and efficiency assessment of biofilter air deodorization using electronic nose prototype
PublicationBiofiltration is one of the techniques used to reduce odorants in the air. It is based on the aerobic degradation of pollutants by microorganisms located in the filter bed. The research presents the possibility of using the electronic nose prototype for monitoring and efficiency assessment of air biofiltration. The study was conducted using model gas mixtures containing representatives of three groups of chemical compounds: n-hexane...
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Selected anionic and cationic surface active agents: case study on the Kłodnica sediments
PublicationSurface active agents (surfactants) are a group of chemical compounds, which are used as ingredients of detergents, cleaning products, cosmetics and functional products. After use, wastes containing surfactants or their degradation products are discharged to wastewater treatment plants or directly into surface waters. Due to their specific properties of SAAs, compounds are able to migrate between different environmental compartments...
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Novel steroid sulfatase inhibitors based on N ‐thiophosphorylated 3‐(4‐aminophenyl)‐coumarin‐7‐O‐sulfamates
PublicationIn the present work, we described convenient methods for the synthesis ofN-thiophosphorylated 3-(4-aminophenyl)-coumarin-7-O-sulfamates as steroid sulfatase(STS) inhibitors. To design the structures of the potential STS inhibitors, molecularmodeling techniques were used. A computational docking method was used to deter-mine the binding modes of the synthesized inhibitors as well as to identify potentialinteractions between specified...