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Search results for: critical micelle concentration
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Solid Phase Microextraction: Apparatus, Sorbent Materials, and Application.
Publicationhe primary objective of this review article is to strategically screen and highlight the advancements in the area of solid phase microextraction (SPME). The plenty of review articles have been written on different aspects of SPME, this review is dedicated to provide the brief but clear overview of the research footprints so produced from SPME. Some of the key advancements in types and designs, coating materials, coating strategies,...
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Mobile Systems (Portable, Handheld, Transportable) for Monitoring Air Pollution
PublicationThe monitoring and analysis of atmospheric air pollutants is a rapidly developing branch of analytical chemistry. The in situ analysis of atmospheric air quality using mobile instrumentation is becoming routine. The article provides information on devices used in various kinds of mobile laboratories. It reviews the portable gas chromatographs and handheld devices used for detecting and determining specific harmful substances in...
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Analysis of MArkers of Exposure to Constituents of Environmental Tobacco Smoke (ETS)
PublicationTobacco smoke is a complex mixture of more than 4000 chemical compounds, many of which are harmful to human health. These compounds belong to various chemical classes, including amides, imides, lactams, carboxylic acids, aldehydes, ketones, alcohols, phenols, amines, hydrocarbons, ethers, and inorganic compounds. There are three types of tobacco smoke streams: the mainstream, the sidestream, and environmental tobacco smoke (ETS)....
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New Polymeric Materials for Solid Phase Extraction
PublicationSolid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward...
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LC-MS and LC-NMR as Complementary Techniques for the Determination of Pharmaceuticals in Dosage Formulations
PublicationPharmaceuticals contain not only pharmacologically active compounds but also a range of excipients. The danger exists that impurities may also be present in such drugs, which may adversely affect their efficacy and even endanger patient health and life. Monitoring the composition of pharmaceutical products is therefore essential. The trace amounts of such impurities in pharmaceuticals are often identified and determined with liquid...
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The Use of Vegetables in the Biomonitoring of Cadmium and Lead Pollution in the Environment
PublicationLead and cadmium emitted from various anthropogenic sources have the ability to accumulate in tissues of living organisms. The phenomenon of accumulation of metals in the body is harmful and undesirable. On the other hand, the ability of plants to accumulate heavy metals from the individual elements of the environment has been used in biomonitoring of pollution. Leaf and root of vegetables have particular predisposition for accumulating...
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Environmentally Oriented Models and Methods for the Evaluation of Drug x Drug Interaction Effects
PublicationThis detailed review compares known and widely used methods for drug interaction estimation, some of which now have historical significance. Pharmaceutical application has been noted as far back as several thousand years ago. Relatively late in the 20th century, however, researchers became aware that their fate and metabolism, which still remain a great challenge for environmental analysts and risk assessors. For the patient’s...
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Revision of Biological Methods for Determination of EDC Presence and Their Endocrine Potential
PublicationEndocrine-disrupting compounds (EDC) are chemicals responsible for disturbances in the hormonal balance of organisms. This group of chemicals includes both egzogenic and endogenic substances or their mixtures that impact functioning of natural hormones in organisms. In the available literature one can find information on the application of chromatographic and related techniques in the analysis of environmental samples for detection,...
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Trace analysis - challenges and problems
PublicationW pracy przedstawiono podstawowe problemy związane z oznaczaniem składników śladowych i ultraśladowych w próbkach o złożonym składzie matrycy. W oparciu o dane literaturowe omówiono sposoby zapobiegania błędom jakimi mogą być obarczone wyniki oznaczeń końcowych.
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Denudation - a convenient method of isolation and enrichment of analytes
PublicationW pracy przedstawiono: podstawy teoretyczne techniki denudacyjnej; rozwiązania konstrukcyjne podstawowych typów urządzeń denudacyjnych; obszar praktycznego wykorzystania technik denudacyjnych.
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Sample preparation and chromatographic analysis of acidic herbicides in soils and sediments
PublicationW pracy przedstawiono różne techniki przygotowania próbek i oznaczania herbicydów z grupy pochodnych fenoli i pochodnych kwasów karboksylowych w próbkach gleby. Opisano wybrane metody wzbogacania i izolacji analitów, m. in.: ekstrakcję za pomocą wodnych roztworów zasad i rozpuszczalników organicznych płynem w stanie nadkrytycznym, wodą w stanie podkrytycznym, cieczą pod zwiększonym ciśnieniem, cieczą wspomaganą mikrofalami. Niski...
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Modern techniques of extraction of organic analytes from environmental matrices.
PublicationW pracy przedstawiono usystematyzowane informacje dotyczące dostępnych jak i nowych technik izolacji i wzbogacania analitów organicznych przed etapem oznaczeń końcowych.
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Preparation of gaseous standard mixtures: methods for controlling the amount of components generated in the process of thermal decomposition of immobilized compounds.
PublicationGazowe mieszaniny wzorcowe odgrywają ważną rolę w ocenie metod analitycznych i urządzeń pomiarowych. W tym przypadku gazowe mieszaniny wzorcowe mogą być traktowane jako specjalny rodzaj materiału odniesienia.Proces walidacji wymaga użycia tzw. matrycowych materiałów odniesienia. Wybór techniki umożliwiającej uzyskanie gazowej mieszaniny wzorcowej o żądanych parametrach użytkowych zależy od natury składników mierzonych i gazu...
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Fate and analysis of pharmaceutical residues in the aquatic environment.
PublicationObecność pozostałości farmaceutyków w poszczególnych elementach środowiska stanowi nowe wyzwanie zarówno z punktu widzenia technologii oczyszczania wód i ścieków, jak i dla analityków, których zadaniem jest opracowanie nowych metodyk analitycznych. Wiele stosowanych leków nie jest w organizmie całkowicie rozkładanych. Często są one wydalane po nieznacznym przekształceniu,lub nawet w niezmienionej postaci. Opisano drogi...
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The Relationships Between BTEX, NOx, and O3 Concentrations in Urban Air in Gdansk and Gdynia, Poland
PublicationThis paper presents the results of atmospheric air quality research conducted in the areas of two shipyard cities: Gdansk and Gdynia (Poland), in the period between March and December 2011. The purpose of the research was focused on determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds in atmospheric air. Passive sampling technique, with Radiello® diffusive passive samplers, was used for BTEX sample collection...
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Synergistic Effects of Propolis Combined with 2-Phenoxyethanol and Antipyretics on the Growth of Staphylococcus aureus
PublicationThe present investigation aimed to assess the combinational effect of commonly usedantipyretics and antiseptics with ethanolic extracts of propolis (EEPs) on the growth inhibition ofStaphylococcus aureus. The broth microdilution checkerboard assay revealed synergistic interactionsbetween all investigated antipyretics, namely acetylsalicylic acid, ibuprofen, and acetaminophen,with EEPs samples. The values of the fractional inhibitory...
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Electrochemical performance of Co3O4/CeO2 electrodes in H2S/H2O atmospheres in a proton-conducting ceramic symmetrical cell with BaZr0.7Ce0.2Y0.1O3 solid electrolyte
PublicationThe electrochemical performance of Co3O4/CeO2 mixed oxide materials as electrodes, when exposed to H2S/H2O atmospheres, was examined employing a proton conducting symmetrical cell, with BaZr0.7Ce0.2Y0.1O3 (BZCY72) as the solid electrolyte. The impact of temperature (700–850 °C) and H2S concentration (0–1 v/v%) in steam-rich atmospheres (90 v/v% H2O) on the overall cell performance was thoroughly assessed by means of electrochemical...
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Wstępna analiza zagrożenia podtopieniami w zlewni Potoku Strzyża w Gdańsku.
PublicationCharakterystyka sieci hydrograficznej Potoku Strzyża. Analiza zagrożenia podtopie - niami z wykorzystaniem hydraulicznego modelu potoku. Przedstawienie oraz analiza wyników obliczeń. Wstępne określenie odcinków newralgicznych z punktu widze - nia zagrożenia powodziowego. Wstępna analiza możliwych przyczyn występowania podtopień na terenie zlewni Potoku Strzyża.
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Effect of Laminar Pulsatile Fluid Flow on Separation of Volatile Organic Compounds from Aqueous Solution by a Hollow Fiber Membrane-Based Process
PublicationIn this study, a laminar pulsatile fluid flow was used for the separation of benzene, toluene, ethylbenzene, and xylene isomers (BTEX) from aqueous solutions. Polyether sulfone hollow fiber membrane has been applied to this process. The effects of BTEX concentration, and feed and extraction flow rates were examined. It was found that the application of the pulsatile fluid flow with...
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A pin-on-disc study of airborne wear particle emissions from studded tyre on concrete road contacts
PublicationStudded tyres wear surfaces of winter roads, generating inhalable airborne particles. In this study, four concrete road materials and two stud geometries were investigated in terms of wear, road material hardness and airborne particle concentration. The sliding contact between studded tyres and road materials was studied using a pin-on-disc machine in a clean chamber. The results show that the normal load and the stud size have...
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The photocatalytic activity of MoS2 electrodes under sunlight illumination
Open Research DataThis dataset contains the results of the photocatalytic activities of the MoS2 and MoS2 modified by SnO2 were assessed through the photocatalytic reduction of Cr6+ under the sunlight illumination. In the experiment, 20 mg of the catalyst was distributed in the K2Cr2O7 aqueous solution (50 mL, 100 mg•L-1). The mixed solution was stirred for 30 min to...
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Gold nanocubic structures functionalization with organic layers
Open Research DataThis dataset contains the XPS spectra obtained for gold nanocubes (AuNC), which were deposited at the gold electrode surface and dried. The AuNC's were first functionalized with either cysteamine in EtOH or mercaptopropionic acid in EtOH. The concentration of these compounds was 20 mM. The interaction of the functionalized with the AuNC surface was...
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Local buckling of composite channel columns
PublicationThe investigation concerns local buckling of compressed flanges of axially compressed composite channel columns. Cooperation of the member flange and web is taken into account here. The buckling mode of the member flange is defined by rotation angle a flange about the line of its connection with the web. The channel column under investigation is made of unidirectional fibre-reinforced laminate. Two approaches to member orthotropic...
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VOCs absorption from gas streams using deep eutectic solvents – A review
PublicationVolatile organic compounds (VOCs) are one of the most severe atmospheric pollutants. They are mainly emitted into the atmosphere from anthropogenic sources such as automobile exhaust, incomplete fuel combustion, and various industrial processes. VOCs not only cause hazards to human health or the environment but also adversely affect industrial installation components due to their specific properties, i.e., corrosive and reactivity....
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Stochastic intervals for the family of quadratic maps
Open Research DataNumerical analysis of chaotic dynamics is a challenging task. The one-parameter families of logistic maps and closely related quadratic maps f_a(x)=a-x^2 are well-known examples of such dynamical systems. Determining parameter values that yield stochastic-like dynamics is especially difficult, because although this set has positive Lebesgue measure,...
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Równolegle przebiegające procesy separacji pianowej jonów Al(III), Cu(II) i Zn(II) z roztworów ich mieszanin
PublicationMetody flotacji jonowej i precypitacyjnej należą do procesów separacji pianowej, wykorzystujących zdolność selektywnej adsorpcji niektórych składników roztworu na powierzchni międzyfazowej gaz – ciecz. Do zalet separacji pianowej zalicza się m.in. niewysokie koszty inwestycyjne i eksploatacyjne oraz wysoką skuteczność w obróbce roztworów rozcieńczonych. Celem pracy jest ocena wpływu kluczowych parametrów na wydajność i przebieg...
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Selective jamming of OFDM transmission in NB-IoT radio interface
PublicationThe paper presents the concept of smart jamming, which involves selective interference aimed at critical components of the OFDM signal. Research verifying the feasibility of this type of electronic attack are described. A realized testbed for jamming real NB-IoT signals in a downlink is presented. The test results demonstrate the feasibility of realizing selective jamming and its greater effectiveness compared to barrage interference.
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Generation of random fields to reflect material and geometric imperfections of plates and shells
PublicationThe paper covers two patterns of random field generation: conditional acceptance – rejection method and Karhunen – Loève expansion. The generation of two-dimensional random fields is essential in plates and shells analysis, allowing for a relevant limit and critical state assessment of geometrically and ma-terially imperfect structures. The features of both generation methods dedicate them to selected problems.
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Study of the Resistance to Influence of Aggressive Liquids on Concrete with Lightweight Aggregate
PublicationThe corrosion of the structure of concrete caused by the aggressive external environment is one of the main problems that can reduce the durability of buildings. The paper analyzes the influence of the type of component on selected properties of lightweight concrete (LWC) exposed to aggressive liquids. When lightweight concrete containing porous aggregates is used, the influence of an aggressive environment may be of particular...
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Experimental Study of the Resistance to Influence of Aggressive Liquids on Lightweight Concrete
PublicationIn light of the scientific research, the corrosion of concrete structures is one of the main problems that may reduce their durability due to the negative impact of the natural environment. The paper analyzes the influence of the type of component on the selected properties of lightweight concrete subjected to the influence of aggressive liquids. Four concrete mixes were prepared with a granular aggregate made of foamed glass (GEGA)...
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Attenuation of Hyperglycemia in Diabetic Rats Assisted by Immobilized Probiotic in Sodium Alginate
PublicationDiabetes mellitus type 2 (DM2) is the most common chronic disease worldwide, characterized mainly by increased glucose concentration in the blood and affecting several organs’ functionality. The daily consumption of probiotic bacteria can help control diabetes and reduce the damage caused. Cell immobilization techniques are a powerful tool that provides physical cell protection to such probiotic bacteria against gastrointestinal...
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Identification of volatile compounds based on the electrocatalytic gas sensor responses
PublicationMeasured response in case of electrocatalytic gas sensors is in form of a voltamperometric characteristic. Current-voltage (I-V) response shape depends on the gas type and its concentration. Such response contains significantly more information comparing with typical electrochemical sensors, but is quite difficult to analyze. When I-V curve contains current peaks, position of such peaks can be used...
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Performance of the flat plate solar collector operated with water-Al2O3 nanofluid
PublicationThe paper discusses the effect of application of water-Al2O3 nanofluid, as a working fluid, on the efficiency of a flat plate solar collector. The mass concentration of nanoparticles was 0.1%, 0.2% and 0.4%. The tests were conducted for two values of radiation of about 1050 W/m2 and 400 W/m2, and volume flow rates of 60 l/h, 120 l/h and 170 l/h. The efficiency was calculated according to recommendations of the Polish Standard....
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Influence of terpenes on indoor air quality
PublicationThe aim of this study was to investigate air quality in hairdresser salons, focusing on terpenes determination. Terpenes are known reactive volatile organic compounds that contribute to secondary organic aerosol formation. Those compounds are frequently found in cosmetic products as fragrance agents. Hairdresser salons are special kind of environment, where secondary organic aerosol concentration may be elevated. One hairdresser...
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Simultaneous Removal of Al, Cu and Zn Ions from Aqueous Solutions Using Ion and Precipitate Flotation Methods
PublicationThis paper presents the results of investigations concerning the simultaneous removal of Al(III), Cu(II), and Zn(II) from dilute aqueous solutions using ion and precipitate flotation methods. The effects of initial solution pH, surface active substance concentration, and the gas velocity on the flotations’ efficiency and course are studied. Experimental results are discussed in terms of physicochemical aspects related to aqueous...
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Al(III) and Cu(II) simultaneous foam separation: Physicochemical problems
PublicationSimultaneous removal of Al(III) and Cu(II) from dilute aqueous solutions by ion and precipitate flotation methods is investigated. Influence of the pH of the initial solution, the surface active collector concentration and the gas flow rate on the final removal ratio and the course of ion and precipitate flotations is presented. Results show that simultaneous flotations of Al(OH)3 and Cu(OH)2 insoluble species occur allowing to...
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Maciej Matciak doktor
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Elastic distortional buckling of thin-walled bars of closed quadratic cross-section
PublicationIn this study a thin-walled bar with closed quadratic cross-section is considered. The elastic stability of axially compressed bar related to the cross-section distortion is investigated. The governing differential equation is derived with aid of the principle of stationary total potential energy. The critical load for the simply supported bar is found in analytical form and it is compared with the FEM solution. Sufficient accuracy...
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Elastic distortional buckling of thin-walled bars of closed quadratic cross-section
PublicationIn this study a tin-walled bar with closed quadratic cross-section is considered. The elastic stability of axially compressed bar related to the cross-section distortion is investigated. The governing differential equatio is derived with aid of the principle of stationary potential energy. The critical load for simply supported bar is found in an analytical form and it is copared with the FEM solution. Sufficient accuracy of the...
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The E-Cohomological Conley Index, Cup-Lengths and the Arnold Conjecture on T 2n
PublicationWe show that the E-cohomological Conley index, that was introduced by the first author recently, has a natural module structure. This yields a new cup-length and a lower bound for the number of critical points of functionals on Hilbert spaces. When applied to the setting of the Arnold conjecture, this paves the way to a short proof on tori, where it was first shown by C. Conley and E. Zehnder in 1983.
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Kerogen to bitumen transformation with respect to host rock environment
PublicationResearch focuses on analyzing the role of rock constituents in kerogen transformation. It includes mineral and organic matter characterization, kerogen and bitumen isolation, quantification, and determination of the critical factors of transformation ratio concerning generating mobile versus less mobile hydrocarbons. The results indicate that the ratio mainly depends on the distribution and type of kerogen in the basin, and secondly...
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Analiza numeryczna i badania doświadczalne wpływu usytuowania stężeń na nośność wyboczeniową modelu kratownicy
PublicationIn the present research the results of experimental test and numerical analyses of a model of a typical truss are presented. The truss linear buckling analysis and non linear static analyses with respect to material and geometrical nonlinearity are conducted. For different stiffnesses and location of braces, the critical load and limit load for the truss are calculated and the threshold bracing stiffness is found. The results of...
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Charakterystyka odcieków powstających w aspekcie wyboru metody ich oczyszcania
PublicationArtykuł obejmuje analizę odcieków generowanych w zakładach utylizacji odpadów w aspekcie ich ilości i jakości oraz możliwości oczyszczania/zagospodarowania, ze szczególnym zwróceniem uwagi na metody biologiczne, najbardziej przyjaznej środowisku. Ponad trzyletnie badania prowadzono na dwóch obiektach zlokalizowanych w woj. pomorskim, gdzie pobierano próbki ścieków technologicznych, powstających podczas sortownia oraz kompostownia odpadów...
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Zmiany składu chemicznego wód podziemnych na obszarze Żuław Wielkich w ujęciu historycznym i współcześnie
PublicationBadania hydrogeologiczne Żuław Wielkich koncentrują się na zasoleniu wód podziemnych. Od początku XX wieku do chwili obecnej obserwuje się wysokie stężenia chlorków, jonów amonowych i mineralizacji we wszystkich poziomach wodonośnych. Uznaje się, iż na przeważającym obszarze nie występują tu warstwy wodonośne o znaczeniu użytkowym, a zasoby wód podziemnych Żuław Wielkich są ograniczone. Przeprowadzone...
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Sample preparation techniques for determination of pesticide residues in food samples
PublicationPesticides are very important in increasing the efficiency and quality of agricultural production. They are applied in many spheres of life, not only in agriculture, and their applications are expanding. Despite their numerous merits, pesticides are some of the most toxic substances contaminating our environment and have a negative impact on the human health. Properties of pesticides such as stability, ability to bioaccumulation...
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Porównanie efektywności biologicznego usuwania związków biogennych w procesach MUCT i A2/O na przykładzie oczyszczalni w Gdańsku
PublicationThis paper presents a comparison of the efficiency of nutrient removal in two different technological systems functioning in WWTP in Gdansk. The upgrade was necessary in order to adjust the parameters of wastewater treatment to more stringent requirements for Total Nitrogen removal (Total Nitrogen concentration < 10 mg/L). Since 2012 the biological treatment line has operated based on modified A2/O process instead of MUCT process....
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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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Removal of Arsenic from Wastewater Using Hydrochar Prepared from Red Macroalgae: Investigating Its Adsorption Efficiency and Mechanism
PublicationArsenic (As) is a prominent carcinogen component produced via both geogenic and anthropogenic processes, posing serious risks to human health. This study aimed to investigate the potential of hydrochar prepared from red macroalgae for removing As from synthetic wastewater. The hydrochar was produced through 5 h hydrothermal carbonization (HTC) treatment at 200 °C, and then, chemically activated with ferric chloride hexahydrate...
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Pre-treatment of bio fraction waste prior to fermentation processes
PublicationCurrent efforts are taken to increase resource efficiency, close material loops, and improve sustainable waste and by-products management. Thus, networking agro-food by-products and converting them into valuable products completely exhausting the potential of the raw material becomes significant. Model lignocellulosic and starch based biomass were subjected to pre-treatment with the application of acidic compounds, i.e. sulphuric...
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In situ study of a composition of outlet gases from biogas fuelled Solid Oxide Fuel Cell performed by the Fourier Transform Infrared Spectroscopy
PublicationThe purpose of this study was to develop a method and software based on the Fourier Transform Infrared Spectroscopy for the in-situ, quantitative analysis of the composition of outlet gases from Solid Oxide Fuel Cell (SOFC). The calibration procedure performed at the beginning of the experiment indicated a polynomial dependence between the concentration of a calibrating gas (CO, CO2, CH4) and the corresponding integrated absorbance in...