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Essential oils as potential anti-staphylococcal agents
PublicationAntibiotic therapy of staphylococcal mastitis is characterized by significantly lower cure rates compared to infections caused by other microorganisms. Thus, it is necessary to search for new, alternative, non-antibiotic agents that are effective in the eradication of these bacteria. The aim of our research was to investigate the antimicrobial, especially anti-staphylococcal potential of a large collection (n=36) of essential oils...
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Potential fertilizing properties of sewage sludge treated in the Sludge Treatment Reed Beds (STRB)
PublicationIn research the fertilizer value of sludge from reed beds is evaluated based on the sampling sludge on different depths from 4 Danish STRB after long periods of stabilization. The dewatering efficiency of sewage sludge in the STRB is comparable to mechanical dewatering. The long-term stabilization of sewage sludge progressively decreases the concentration of organic matter due to the process of humification. The aim of the work...
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Surfactants: a real threat to the aquatic geoecosystems of lobelia lakes
PublicationLobelia lakes are valuable elements of the natural environment. They are characterised by low trophy, mainly in-forest location and a high transparency of water. However, similarly to other surface waters, they are subjected to increasing anthropogenic pressures, a good indicator of which is the level of surfactants, also called surface-active agents (SAAs). The aim of the study was to evaluate the intensity of anthropogenic pressures...
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Reliability of nitrogen removal processes in multistage treatment wetlands receiving high-strength wastewater
Publicationreatment wetlands have been proved to be more effective than conventional treatment processes in case of high-strength wastewater containing high concentrations of ammonium nitrogen and recalcitrant organic matter. In this study nitrogen removal processes and reliability of nitrogen removal at two identical pilot-scale multistage treatment wetlands (MTWs) receiving real, non-synthetic wastewater were discussed. The wastewater discharged...
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SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART I. LINEAR ALKYLBENZENE SULPHONATES (LAS)
PublicationSurfactants are a group of compounds with specific physico-chemical properties and therefore they are used in many spheres of human activity. Surface-active substances undergo various physico-chemical transformations, what enables their migration between different elements of the environment and may lead to its pollution. Selected anionic surfactants were determined in samples of water from the Klodnica river (25 samples) and bottom...
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Influence of the presence of rhamnolipids and ionic cross-linking conditions on the mechanical properties of alginate hydrogels.
Open Research DataThe dataset contains the results of determination the effect of rhamnolipids concentration, calcium chloride concentration and ionic cross-linking time on the mechanical properties of alginate hydrogels prepared by immersing the alginate mixture limited by the dialysis membrane in an appropriate cross-linking solution containing calcium ions. The mechanical...
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Freshening of salinized groundwater in Gdańsk Quaternary aquifer
PublicationThe main Quaternary aquifer in the Gdańsk region connects directly with salt waters of the Martwa Wisła River and the Gulf of Gdańsk. This aquifer has been used for many years by large municipal and industrial intakes located on the marine lowlands, with maximum output 6236 m3 /h in 1985. Owing to an intensive exploitation, groundwater in the area of the Old Gdańsk has been salinized by intrusion of salt water from the Martwa Wisła...
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Determination of toxic gases based on the responses of a single electrocatalytic sensor and pattern recognition techniques
PublicationA response from an electrocatalytic gas sensor contains fingerprint information about the type of gas and its concentration. As a result, a single gas sensor can be used for the determination of different gases. However, information about the type of gas and its concentration is hidden in the unique shape of the current–voltage response and it is quite difficult to explore. One of the ways to get precise information about the measured...
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The gaseous messenger carbon monoxide is released from the eye into the ophthalmic venous blood depending on the intensity of sunlight
PublicationCircadian and seasonal rhythms in daylight affect many physiological processes. In the eye, energy of intense visible light not only initiates a well-studied neural reaction in the retina that modulates the secretory function of the hypothalamus and pineal gland, but also activates the heme oxygenase (HO) to produce carbon monoxide (CO). This study was designed to determine whether the concentration of carbon monoxide (CO) in the...
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Complementary use of GCxGC–TOF–MS and statistics for differentiation of variety in biosolid samples
PublicationFormation of biosolid cakes, which are one of the main wastes generated in wastewater treatment plants, is connected with emission of many hazardous chemical compounds, including odoriferous ones. To optimize particular processes of biosolid cake processing, it is necessary to assess chemical composition of the gas mixtures containing the compounds released from the cakes. The paper proposes application of two-dimensional gas chromatography...
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Arctic catchment as a sensitive indicator of the environmental changes: distribution and migration of metals (Svalbard)
PublicationArctic regions experience metal pollution, despite their remote location, and the distribution and migration of those metals determine their potential impact on the local environment. Here, a High-Arctic catchment (Revelva, Svalbard) located remotely from human-induced pollution sources is studied with respect to the distribution and migration of chosen trace elements (Ag, Al, As, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Cs, Mo, Ni, Pb,...
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Phospholipid-functionalized gold electrode for cellular membrane interface studies - interactions between DMPC bilayer and human cystatin C
PublicationThis work describes the electrochemical studies on the interactions between V57G mutant of human cystatin C (hCC V57G) and membrane bilayer immobilized on the surface of a gold electrode. The electrode was modified with 6-mercaptohexan-1-ol (MCH) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). DMPC was used as a membrane mimetic for monitoring electrochemical changes resulting from the interactions between the functionalized...
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Determination of high-intensity sweeteners in beverages by high-performance liquid chromatography with mass spectrometry detection.
PublicationThe objective of the present study was to measure the concentration of nine high intensity sweeteners (acesulfame-K, aspartame, alitame, cyclamate, dulcin, neohesperidin dihydrochalcon, neotame, saccharin and sucralose) in different types of beverages available on the polish market. The proposed methodology reported here consists of a extraction with buffer composed of formic acid and N,N-diisopropylethylamine (pH 4.5) followed...
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Electronic structure calculations in electrolyte solutions: Methods for neutralization of extended charged interfaces
PublicationDensity functional theory (DFT) is often used for simulating extended materials such as infinite crystals or surfaces, under periodic boundary conditions (PBCs). In such calculations, when the simulation cell has non-zero charge, electrical neutrality has to be imposed, and this is often done via a uniform background charge of opposite sign (“jellium”). This artificial neutralization does not occur in reality, where a different...
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Adipokine and cytokine levels in patients with adrenocortical cancer, subclinical Cushing's syndrome and healthy controls
PublicationIntroduction In recent years researchers have focused at hormonal activity in Cushing’s syndrome (CS) in connection with metabolic disorders and the role of adipokines and cytokines secreted by the adipose tissue. The aim of the study was to investigate levels of adipokines and cytokines in patients with: subclinical CS (SCS) – in relation to hormonal parameters of hypercortisolemia, and, adrenocortical cancer (ACC). Materials...
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Selected adipocytokines in patients with an incidentally discovered pheochromocytoma
PublicationBACKGROUND: Adipose tissue secretes many adipokines and cytokines, which may be an additional risk factor of cardiovascular and metabolic diseases in patients with an incidentally discovered pheochromocytoma (PHEO). The aim of the study was to investigate levels of selected adipocytokines in these patients. METHODS: This prospective study included 12 patients with an incidentally discovered PHEO and 18 healthy participants. In...
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Marek Kowalewski dr
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Limited selectivity of amperometric gas sensors operating in multicomponent gas mixtures and methods of selectivity improvement
PublicationIn recent years, smog and poor air quality have became a growing environmental problem. There is a need to continuously monitor the quality of the air. The lack of selectivity is one of the most important problems limiting the use of gas sensors for this purpose. In this study, the selectivity of six amperometric gas sensors is investigated. First, the sensors were calibrated in order to find a correlation between the concentration...
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Development Of Dynamic Method For Evaluation Of Corrosion Rate On The Example Of Organic Corrosion İnhibitor
PublicationMeasurements of the corrosion rate belong to the most important aspects of materials science. In order to reduce material loss corrosion inhibitors are used. However selection of proper inhibitor should be based on evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character so physicochemical parameters are changing in time. Most of actually used methods...
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Structural Properties and Water Uptake of SrTi1−xFexO3−x/2−δ
PublicationIn this work, Fe-doped strontium titanate SrTi1−xFexO3−x/2−δ, for x = 0–1 (STFx), has been fabricated and studied. The structure and microstructure analysis showed that the Fe amount in SrTi1−xFexO3−x/2−δ has a great influence on the lattice parameter and microstructure, including the porosity and grain size. Oxygen nonstoichiometry studies performed by thermogravimetry at different atmospheres showed that the Fe-rich compositions...
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Bisphenols (A, S, and F) affect the basic hormonal activity determined for pharmaceuticals – Study of Saccharomyces cerevisiae
PublicationPharmaceuticals and analogs of bisphenol A (BPA) are increasingly threatening environmental pollutants. In this study, mixtures of selected pharmaceuticals (diclofenac sodium salt, chloramphenicol, oxytetracycline hydrochloride, fluoxetine hydrochloride, estrone, ketoprofen, progesterone, gemfibrozil and androstenedione) were prepared with BPA and its two analogs (namely, bisphenols F and S) at such ratios to reflect environmentally...
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The influence of meteorological conditions and anthropogenic activities on the seasonal fluctuations of BTEX in the urban air of the Hanseatic city of Gdansk, Poland
PublicationThe results of studies conducted in Gdansk in the period from January to December 2013 and focused on the determination of BTEX in the atmospheric air are presented. At the stage of the isolation and/or enrichment of analytes from the gaseous medium, a passive sampling technique—Radiello® diffusive passive samplers, was applied. The time-weighted average annual concentration of benzene, toluene, ethylbenzene, and total xylenes...
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Release of potassium from actvated sludge as a resultof use peroxyacetic acid = Uwalnianie potasu z osadu czynnego pod wpływem kwasu nadoctowego
PublicationThe phenomenon of potassium efflux (GGKE - glutathione-gated potassium efflux) from the calls of activated sludge bacteria in the result of peroxyacetic acid (CH3CO3H) dosing was investigated. Addition of the strong oxidant to the activated sludge environment caused activation of the defense mechanisms of bacterial cells, related to glutathione transformations, which resulted in the significant increase of potassium ions concentration....
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Determination of cyanide in urine and saliva samples by ion chromatography with pulsed amperometric detection
PublicationCommonly known as a highly toxic chemical, cyanide is also an essential reagent for many industrial processes. It naturally occurs in plant seeds as a cyanogenic glycosides. Another relatively common mode of cyanide exposure is inhalation of environmental tobacco smoke. This study concerns importance to determine cyanide ion in human biological samples. Urine and saliva samples were collected healthy volunteers exposed to tobacco...
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New potent steroid sulphatase inhibitors based on 6-(1-phenyl-1H-1,2,3-triazol-4-yl)naphthalen-2-yl sulphamate derivatives
PublicationIn the present work, we report a new class of potent steroid sulphatase (STS) inhibitors based on 6-(1-phenyl-1H-1,2,3-triazol-4-yl)naphthalen-2-yl sulphamate derivatives. Within the set of new STS inhibitors, 6-(1-(1,2,3-trifluorophenyl)-1H-1,2,3-triazol-4-yl)naphthalen-2-yl sulphamate 3L demonstrated the highest activity in the enzymatic assay inhibiting the STS activity to 7.98% at 0.5 µM concentration. Furthermore, to verify...
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Optical-Spectrometry-Based Method for Immunosuppressant Medicine Level Detection in Aqueous Solutions
PublicationIn this paper, an investigation into detecting immunosuppressive medicine in aqueous solutions using a spectrometry-based technique is described. Using optical transmissive spectrometry, absorbance measurements in the spectra range from 250 nm to 1000 nm were carried out for different cyclosporine A (CsA) concentrations in aqueous solutions. The experiment was conducted for samples both with and without interferent substances—glucose...
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Reject water and landfil leachate treatment with hydrophyte method - preliminary results
PublicationTreatment of landfill leachate (LL) and reject water (RWC) from dewatering of digested sludge in WWTPs have become one of the actual problems. Treatment of both types of wastewater is in many cases very costly and difficult due to quality and quantity fluctuations in time as well as high concentrations of specific pollutants. In case of our investigation the TSS concentration in RWC was two times higher than in LL. The shere of...
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Antifungal Activity and Synergism with Azoles of Polish Propolis
PublicationThe aim of our work was to check if one of the products of natural origin, namely honey 19 bee propolis may be an alternative or supplement to currently used antifungal agents. The activity 20 of 50 ethanolic extracts of propolis (EEPs), harvested in Polish apiaries, was tested on a group of 69 21 clinical isolates of C. albicans. Most of the EEPs showed satisfactory activity, with minimum 22 fungicidal concentrations (MFC) mainly...
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Spatial Differences in the Chemical Composition of Surface Water in the Hornsund Fjord Area: A Statistical Analysis with A Focus on Local Pollution Sources
PublicationSurface catchments in Svalbard are sensitive to external pollution, and yet what is frequently considered external contamination may originate from local sources and natural processes. In this work, we analyze the chemical composition of surface waters in the catchments surrounding the Polish Polar Station in Svalbard, Hornsund fjord area. We have pooled unpublished and already published data describing surface water composition...
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A High-Arctic flow-through lake system hydrochemical changes: Revvatnet, southwestern Svalbard (years 2010–2018)
PublicationLake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010–2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system...
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Environmental characteristics of a tundra river system in Svalbard. Part 1: Bacterial abundance, community structure and nutrient levels
PublicationThe Arctic hosts a set of unique ecosystems, characterised by extreme environmental conditions and undergoing a rapid change resulting from the average temperature rising. We present a study on an aquatic ecosystem of the Revelva catchment (Spitsbergen), based on samples collected from the lake, river and their tributaries, in the summer of 2016. The landscape variety of the study site and the seasonal change in the hydrological...
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The influence of phosphorus fractions in bottom sediments on phosphate removal in semi-natural systems as the 3rd stage of biological wastewater treatment
PublicationThe research was carried out in two semi-natural systems (the polishing ponds in Swarzewo and the free water surface constructed wetland in Zarnowiec) in Poland. They were built as the 3rd stage of a conventional mechanical–biological wastewater treatment plant. These systems were built to improve the quality of the effluent of treated wastewater. In the polishing ponds and FWS wetland system, suspended solids, organic matter as...
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Coupling transformation of carbon, nitrogen and sulfur in a long-term operated full-scale constructed wetland
PublicationThe coupling transformation of carbon, nitrogen and sulfur compounds has been studied in lab-scale and pilot-scale constructed wetlands (CWs), but few studies investigated full-scale CW. In this study, we used batch experiments to investigate the potentials of carbon, nitrogen and sulfur transformation in a long-term operated, full-scale horizontal subsurface flow wetland. The sediments collected from the HSFW were incubated for...
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Application of ion chromatography with pulsed amperometric detection for the determination of trace cyanide in biological samples, including breast milk
PublicationCyanide (CN) is the biomarker of exposure to the components of tobacco smoke, although its presence in biological samples is also due to the consumption of products containing cyanogenic glycosides. In this work, we determine the concentration of the free cyanide in urine, saliva and breast milk matrices, using ion chromatography with pulsed amperometric detection (IC-PAD). IC-PAD is an emerging method, with only few documented...
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The application of moving bed biofilm reactor to denitrification process after trickling filters
PublicationThe paper presents research of a prototype moving bed biofilm reactor (MBBR). The device was used for the post-denitrification process and was installed at the end of a technological system consisting of a septic tank and two trickling filters. The concentrations of suspended biomass and biomass attached on the EvU Perl moving bed surface were determined. The impact of the external organic carbon concentration on the denitrification...
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Can sodium 1-alkylsulfonates participate in the sodium dodecyl sulfate micelle formation?
PublicationThe aggregation behavior of sodium dodecyl sulfate (SDS) was studied in an aqueous solution in the presence of increasing concentrations of selected sodium 1-alkylsulfonates, namely sodium 1-octanesulfonate, sodium 1-decanesulfonate, and sodium 1-dodecanesufonate. The critical micelle concentration (CMC) of SDS was determined by conductivity and fluorescence intensity measurements. The steady-state fluorescence quenching experiments...
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Gold nanocubic structures agglomeration when put on conductive surfaces
Open Research DataThis dataset contains SEM images of gold nanocubes (AuNC), which were deposited at the conductive Si wafer surface and dried. The deposition method, the solvent used and AuNC concentration have a significant influence on the homogeneous distribution and their agglomeration at the surface, further influencing the electrochemical characteristics of the...
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Calculations of notch stress factor of a thin-walled spreader bracket fillet weld with the use of a local stress approach
PublicationPresence of geometric notches in welded joints causes concentration of strains and stresses, therefore reducing fatigue strength of such joints. This article presents an analysis of stress concentrations in a fillet weld of a spreader mounting bracket on a small sailing yacht. The aim of this article is to direct the attention of designers, manufacturers and regulatory bodies to issues of fatigue cracks that form in brackets fastening...
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Analysis of cell cycle distribution
Open Research DataThe dataset comprehensively details the distribution of A549, H226, and H460 cell lines in various cell cycle phases following treatment with the IC90 concentration of selected anthraquinones. The analysis was performed using the Flowing Software 2.
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New procedure for the control of the treatment of industrial effluents to remove volatile organosulfur compounds
PublicationWe present a new procedure for the determination of volatile organosulfur compounds in samples of industrial effluents using dispersive liquid–liquid microextraction and gas chromatography with flame photometric detection. Initially, the extraction parameters were optimized. These included: type and volume of extraction solvent, volume of disperser solvent, salting out effect, pH, time and speed of centrifugation as well as extraction...
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Development of dynamic method for evaluation of inhibition efficiency on the example of 8-hydroxyquinolin
PublicationSelection of a proper inhibitor should be based on the evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character due to changing physicochemical conditions of the environment and corroding metal surface. Most of actually used methods are stationary or contain assumptions which highly influences obtained values. Development of new dynamic method, based on modified EIS, allows...
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Analysis and bioanalysis: an effective tool for data collection of environmental conditions and processes
PublicationReliable information that allows us to estimate the state of the environment and to forecast changes in the ecosystem are constantly required. Increasing environmental consciousness and dynamic development of analytical techniques are the main reasons for determining the wide range of pollutants occurring at very low concentrations in complex matrix samples. The presence and concentration of many of those pollutants in the environment...
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Multistage treatment wetland for treatment of reject waters from digested sludge dewatering
PublicationThe paper presents the influence of sewage composition on treatment in pilot-scale facility for reject waters (RW) from sewage sludge centrifugation. The facility consisted of mechanical (two tanks with 10 d retention each) and biological parts composed of three subsurface flow reed beds working in batch. Two years of monitoring of the facility proved high efficiency removal of predominant pollutants: COD 75–80%, BOD 82.2–95.5%...
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The effect of raw material type on endotoxin content .
Open Research DataThe datasets contain the results of determining the effect of raw material type on endotoxin content as well as the effect of purification methods. The endotoxin concentration was determined using the PyroGene Recombinant Factor C Endpoint Fluorescent Assay. Beckmann-Kenko sodium alginate and Chemat sodium salt of alginic acid were used for the assays....
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Gold nanocubic structures agglomeration when put on conductive surfaces
Open Research DataThis dataset contains SEM images of gold nanocubes (AuNC), which were deposited at the conductive Si wafer surface and dried. The deposition method, the solvent used and AuNC concentration have a significant influence on the homogeneous distribution and their agglomeration at the surface, further influencing the electrochemical characteristics of the...
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Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
PublicationDue to human activities, the concentrations of organometallic compounds in all parts of the environment have increased in recent decades. The toxicity and some biochemical properties of mercury and tin present in the environment depend on the concentration and chemical form of these two elements. The ever-increasing demand for determining compounds at very low concentration levels in samples with complex matrices requires...
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Study of the Anti-Staphylococcal Potential of Honeys Produced in Northern Poland
PublicationThe antimicrobial activity of 144 samples of honeys including 95 products from apiaries located in Northern Poland was evaluated. The antibacterial activity of those natural products, their thermal stability, and activity in the presence of catalase was investigated by microdilution assays in titration plates. The MTT assay was performed for the determination of anti-biofilm activity. Spectrophotometric assays were used for the...
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Enhanced boron doping of thin diamond films grown in deuterium-rich microwave plasma
PublicationThe boron-doped diamond thin films were growth in deuterium rich microwave plasma in CVD process. The mechanism of influence of plasma composition on boron doping level was studied using optical emission spectroscopy. Deuterium rich plasma results in an increased dissociation of B2H6 precursor and intense boron-radicals' production. In consequence, a higher doping level of diamond films was observed by means of Laser Induced Breakdown...
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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
PublicationThe 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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The speciation of selected heavy metals in sewage sludge stabilized in reed basins
PublicationThe aim of the work was to determine influence of time on organic matter content, nutrients concentrations as well as speciation of selected heavy metals (Cd, Pb, Ni, Cr, Cu and Zn) in sewage sludge stabilized in reed basins during 7-15 years. The analyzed sewage sludge was collected from reed basins from four municipal WWTPs located in Denmark serving from 9 000 to 40 000 pe in Vallo, Rudkøbing, Nakskov and Helsinge. Sewage...