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Wyniki wyszukiwania dla: nasal discharge samples
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Evaluation of polycaprolactone as a new sorbent coating for determination of polar organic compounds in water samples using membrane–SPME
PublikacjaCommercially available solid-phase microextraction fibers used for isolation of polar analytes are based on the adsorption phenomenon. In consequence, typical limitations bonded with analytes displacement and matrix effects are very frequent. In the present study, alternative solution is described. Polycaprolactone (PCL) was used for the first time as sorbent to isolate polar organic compounds from water samples using the membrane–solid-phase...
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Comparative evaluation of different methods for determining phytochemicals and antioxidant activity in products containing betalains - Verification of beetroot samples
PublikacjaThis study presents methods that can be used to assess the health quality of products containing betalains. The paper compares and verifies data on the phytochemical composition of three different pigmented beetroot cultivars using spectrophotometric, HPLC-DAD, HPTLC and LC-Q-Orbitrap-HRMS techniques. Additionally, we compared the total antioxidant activity in both the cell-free and cellular systems. Betalain contribution to antioxidant...
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Analytical procedures for the determination of fuel combustion products, anti-corrosive compounds, and de-icing compounds in airport runoff water samples
PublikacjaThe purpose of this study is to propose and evaluate new procedures for determination of fuel combustion products, anti-corrosive and de-icing compounds in runoff water samples collected from the airports located in different regions and characterized by different levels of the activity expressed by the number of flights and the number of passengers (per year). The most difficult step in the analytical procedure used for the determination...
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Microplastics in atmospheric dust samples of Sistan: sources and distribution
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Simultaneous Analysis of Heavy Metal Concentration in Soil Samples
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Preparation of soil and sediment samples for the determination of organometallic compounds
PublikacjaZwiązki metaloorganiczne są szeroko stosowane niemal we wszystkich gałęziach przemysłu. W wyniku ich emisji, zarówno ze źródeł naturalnych jak i antropogenicznych, nastąpiło ich rozprzestrzenienie w środowisku, w którym ulegają szeregowi przemian chemicznych. Niektóre z tych związków charakteryzują się wysoką toksycznością. W oparciu o literaturę naukową dotyczącą procedur oznaczania wybranych związków metaloorganicznych rtęci,...
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Odour Samples Degradation During Detention in Tedlar® Bags
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Analytical procedures used in examining human urine samples.
PublikacjaŹródłem informacji o stanie środowiska mogą być zarówno wyniki badań próbek części nieożywionej (woda, gleba, powietrze) jak i części biotycznej, w tym także tkanek i płynów ustrojowych człowieka, który jest nieustannie narażony na działanie szerokiego spektrum ksenobiotyków. Badanie płynów ustrojowych człowieka (głównie krwi i moczu) może być bardzo użyteczną i interesującą drogą do uzyskania informacji o stanie środowiska....
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An analysis of pesticides and polychlorinated biphenyls in biological samples and foods.
PublikacjaPestycydy i polichlorowane bifenyle występują w środowisku w małych ilościach, ale ulegając kumulacji, stanowią zagrożenie dla ludzi i zwierząt. Najbardziej zagrożony jest człowiek stojący na szczycie łańcucha pokarmowego. Świadomość niebezpieczeństw jakie niesie ze sobą postępujące zanieczyszczenie środowiska w połączeniu z nowoczesnymi środkami zaradczymi powinna zmniejszyć do minimum możliwość występowania zatruć u ludzi i powstania...
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Experimental Evaluation of ND: YAG Laser Parameters and Sample Preparation Methods for Texturing Thin AISI 316L Steel Samples
PublikacjaIn mechanical and material engineering, the effect of laser texturing depends on many factors besides device specification, primarily the properties of the materials being processed, and, secondly, the preparation of the sample. Laser texturing of thin (<5 mm) samples is mostly performed utilizing short-pulse lasers, but depending on the power of the laser beam, the process can also be performed by using continuous operation lasers....
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Application of analytical procedure based on accelerated solvent extraction and ion chromatography technique for determination of thiocyanate and other inorganic ions in human placenta samples
PublikacjaExposure of a pregnant woman during pregnancy is a special case of exposure to toxic substances. Samples of placenta collected for the studies had been prepared with the technique of accelerated solvent extraction and later analyzed for the presence of thiocyanate ion and other inorganic ions, with the use of the technique of ion chromatography. The concentration of thiocyanate ion in placenta samples collected from active smokers...
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Head-Space SPME for the Analysis of Organophosphorus Insecticides by Novel Silica IL-Based Fibers in Real Samples
PublikacjaThis work demonstrates the suitability of a newly developed ionic liquid (IL)-based silica SPME fiber for the determination of seven organophosphorus insecticides in cucumber and grapefruit samples by headspace solid-phase microextraction (HS-SPME) with a gas chromatography–flame ionization detector (FID). The sol-gel method released four different sorbent coatings, which were obtained based on a silica matrix containing ILs immobilized...
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Determination of polybrominated diphenyl ethers (PBDEs) in dust samples collected in air conditioning filters of different usage – method development
PublikacjaThis study presents the results of studies aimed at the development of an analytical procedure for separation, identification, and determination of PBDEs compounds in dust samples collected from automotive cabin air filters and samples collected from filters installed as part of the air purification system in academic facilities. Ultrasound-assisted dispersive solid phase extraction (UA-dSPE) was found to perform better in terms...
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Discrepancies in determination of biogenic amines in beer samples by reversed phase and hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry
PublikacjaBiogenic amines (BAs) are nitrogenous organic bases occurring mainly in fermented food and beverages as a result of free amino acids bacterial decarboxylation. The reversed phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC) based methods were compared in terms of usefulness for determination of BAs in beer samples. Analysis of BAs with the use of RPLC method were carried out after their...
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Determination of selected parameters/ analytes in surface water samples collected in the surroundings of the capital of Spitsbergen (Longyearbyen)
PublikacjaPolar regions are extremely sensitive to pollution such as harmful gases, particles or toxic substances which affect the Arctic climate and ecosystems. Spitsbergen, as well as all Arctic region, because of its geographically distant location and lack of industry sector, should be free of chemical pollution. Despite this, many pollutants could be found in the Polar environment, for example in freshwaters. Their occurrence is related...
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Development of different methods for drugs and psychoactive substances extraction from hair samples and their identification based on HPLC-ESI-QTOF analysis
PublikacjaOver the past decade, the use of non-controlled designer drugs and drug of abuse has rapidly increased. Hair, as a human matrix, enables detection of drugs incorporated into its structure. Studies of presence and identification of drug metabolites in human hair samples has been performed using liquid chromatography electrospray ionization quadrupole time of flight mass spectrometry (HPLC-ESI-QTOF-MS) with steady alternation of...
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Chemical Derivatization Processes Applied to Amine Determination in Samples of Different Matrix Composition
PublikacjaAmines are important biological compounds, and so their analysis and monitoring in various matrices is worthy of investigation and development.Due to the polar nature of amines, chromatographic analysis of free amines is generally unsatisfactory owing to adsorption and decomposition of the solute on the column, resulting in peak tailing and losses. Therefore, many derivatization reactions are employed to reduce the polarity, improve...
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Optimization of vortex-assisted supramolecular solvent-based liquid liquid microextraction for the determination of mercury in real water and food samples
PublikacjaA novel method was developed for sample preparation for spectrophotometric determination of Hg(II) in water and food samples. The method was based on vortex-assisted supramolecular solvent-assisted liquid-liquid microextraction (VA-SUPRASs-LLME). Analytical parameters such as pH, chelating agent, solvent type and volume, vortex time and salting out effect were optimized. Surface and normal probability plots were drawn for the variables...
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Application of ion chromatography with pulsed amperometric detection for the determination of trace cyanide in biological samples, including breast milk
PublikacjaCyanide (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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Computer-aided analysis of signals from a low-coherence Fabry-Perot interferometer used for measurements of biological samples
PublikacjaThe aim of the study was to develop an automated computer-aided system for analysis of spectrograms obtained from measurements of biological samples performed with a low-coherence Fabry-Pérot interferometer. Information necessary to determine dispersion characteristics of measured materials can be calculated from the positions of the maxima and minima that are present in their spectra. The main challenge faced during the development...
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Hydrophobic deep eutectic solvents as “green” extraction media for polycyclic aromatic hydrocarbons in aqueous samples
PublikacjaThe paper presents novel nonionic and hydrophobic deep eutectic solvents which were synthesized from natural compounds, i.e., thymol, ±camphor, decanoic and 10-undecylenic acids. Fundamental physicochemical properties of the synthesized deep eutectic solvents were determined, followed by their application as extractants in ultrasound-assisted dispersive liquid-liquid microextraction to isolate and enrich polycyclic aromatic hydrocarbons...
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DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES - PART I. CATIONIC COMPOUNDS = Oznaczanie Surfaktantów W Próbkach Środowiskowych. Część I. Związki Kationowe
PublikacjaCompounds from the group of cationic surfactants are widely applied in household, industrial, cleaning, disinfectant, cosmetic and pharmaceutical products as their specific properties (antimicrobial, emulsifying, anticorrosion, softening). After use, cationic surfactants are disposed to wastewater-treatment plants and finally with effluent water to surface waters due to their incomplete degradation. Moreover, they can freely circulate...
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Deep eutectic solvents based assay for extraction and determination of zinc in fish and eel samples using FAAS
PublikacjaA 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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Quantification of unconjugated and total ibuprofen and its metabolites in equine urine samples by gas chromatography–tandem mass spectrometry: Application to the excretion study
PublikacjaIbuprofen (IBU) is a widely used nonsteroidal anti-inflammatory drug (NSAID) in human and also veterinary medicine. NSAIDs are usually highly metabolized compounds in horses; they are often present in equine urine, mostly in their conjugated forms (glucuronides). Thus, hydrolysis to cleave the glucuronide linkage prior to anti-doping analysis is often necessary for improving detection. In this study, unconjugated and total IBU...
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Decolorization of organic dyes solution by atmospheric pressure glow discharge system working in a liquid flow-through mode
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Deep submarine groundwater discharge indicated by pore water chloride anomalies in the Gulf of Gdańsk, southern Baltic Sea
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Correction to: The chemistry and toxicity of discharge waters from copper mine tailing impoundment in the valley of the Apuseni Mountains in Romania
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Ultra-Wideband Vivaldi Antenna with an Integrated Noise-Rejecting Parasitic Notch Filter for Online Partial Discharge Detection
PublikacjaPower transformers and gas-insulated switchgear (GIS) play crucial roles in electrical power grids. However, they may suffer from degradation of insulation material due to wear and tear, leading to their imminent failure. Partial discharges (PDs) are an initial sign of insulation materials degradation which emit signals spanning various physical domains, including electromagnetic. PDs are temporally narrow, high-frequency, stochastic...
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Analytical procedures for determination of cocaine and its metabolites in biological samples
PublikacjaThe dangerous effects and increased usage of illicit drugs have inspired the development of analytical methodologies. We based our review of analytical procedures for determination of cocaine (COC) and its metabolites on literature from the past two decades. Our main aim was to compare the capabilities of different analytical techniques. The diversity of matrices from which COC is determined (e.g., blood, hair, saliva, plasma,...
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Comparison of extraction techniques of robenidine from poultry feed samples
PublikacjaW publikacji opisano wykorzystanie różnych technik ekstrakcji kokcydistatyków (na przykładzie robenidyny) z próbek pasz zwierzęcych. W trakcie badań porównano wpływ różnych parametrów ekstrakcji na współczynniki odzysku analitu. Wśród wykorzystanych technik ekstrakcji wymienić należy: ekstrakcję za pomocą rozpuszczalnika wspomaganą ultradźwiękami oraz mikrofalami, ekstrakcję w aparatach Soxhleta i Soxteca a także ekstrakcję przez...
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Real-Time Volatilomics: A Novel Approach for Analyzing Biological Samples
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Determination of metronidazole residues in water, sediment and fish tissue samples
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Determination and identification of organic acids in wine samples. Problems and challenges.
PublikacjaFor long time, organic acids were underestimated. However, during last two decades there is an increasing interest of natural compounds having antioxidant, antimicrobial and anti-inflammatory properties thus organic acids are very preferable. Wine stands as one of the sources of organic acids since they are responsible for its organoleptic and aestethic character. Nevertheless, it is important to not exceed acceptable level of...
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Development and validation of UHPLC method for the determination of cyclosporine A in biological samples
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Low-order models from FD-TD time samples
PublikacjaNiniejszy artykuł zawiera opis szeregu kryteriów pozwalających na automatyczne tworzenie wysokiej jakości modeli sygnałów czasowych uzyskanych w drodze symulacji obwodów wysokiej częstotliwości metodą różnic skończonych w dziedzinie czasu. Podany jest szczegółowy opis selekcji kluczowych parametrów modeli takich jak wybór długości ciągu użytego do konstrukcji modeli, współczynnika decymacji silnie nadpróbkowanego przebiegu w dziedzinie...
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Miniaturized, green salting-out liquid–liquid microextraction coupled with GC–MS used to evaluate biogenic amines in wine samples
PublikacjaMonitoring of the biogenic amines (BAs) content in food products, including wine, is important due to the health and safety of consumers and from the quality control point of view. In a given study, simultaneous derivatization and salting-out liquid–liquid microextraction (SALLME) coupled with GC–MS for BAs determination from wine samples was developed. For the optimization the Box-Behnken design was applied, where three independent...
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Optimization of vortex-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction for quantification of niclosamide in real samples
PublikacjaIn this manuscript, a green and fast vortex-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction (VA-HMDES-DLPME) method was developed for the selective extraction and determination of niclosamide in read samples, including rice, medicine tablets, and water samples. Here, hydrophobic magnetic deep eutectic solvents were used as the extracting solvent without requiring any centrifugation...
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A geophysical, geochemical and microbiological study of a newly discovered pockmark with active gas seepage and submarine groundwater discharge (MET1-BH, central Gulf of Gdańsk, southern Baltic Sea)
PublikacjaHigh-resolution bathymetric data were collected with a multi-beam echosounder in the southern part of the Baltic Sea (region MET1, Gulf of Gdańsk) revealing the presence of a 10 m deep and 50 m in diameter pockmark (MET1-BH) on the sea bottom (78.7 m). To date, no such structures have been observed to reach this size in the Baltic Sea. The salinity of the near-bottom water in the pockmark was about 2 PSU (about 31.22 mmol/l...
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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
PublikacjaA 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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Analysis of pesticide residue in tomato samples using analytical protocol based on application of QuEChERS technique and GC-ECD system
PublikacjaQuEChERS sample preparation method was used for the determination of 10 pesticides and their metabolites in tomato samples, coupled to gas chromatography with electron capture detector (GCECD). The experimental parameters including oven temperature program, amount of the sample and purifying agent were optimized. The GC-ECD method was validated in terms of linearity, selectivity and recovery. The limits of detection (LODs) of the...
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Integration of Fuzzy AHP and Fuzzy TOPSIS Methods for Wire Electric Discharge Machining of Titanium (Ti6Al4V) Alloy Using RSM
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Spectroscopic Characterization of Miniaturized Atmospheric-Pressure dc Glow Discharge Generated in Contact with Flowing Small Size Liquid Cathode
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Application potential of dummy molecularly imprinted polymers as solidphase extraction sorbents for determination of low-mass polybrominated diphenyl ethers in soil and sediment samples
PublikacjaDespite the introduction of restrictive regulations in the USA and the European Union, polybrominated diphenyl ethers (PBDEs) are still found in various types of environmental and biological samples at significant concentration levels. The presence of these persistent organic pollutants in the environment raises important issues because of their negative impact on immunological and neurological systems, and on the hormonal balances...
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Occurrence and levels of polybrominated diphenyl ethers (PBDEs) in house dust and hair samples from Northern Poland; an assessment of human exposure
PublikacjaPolybrominated diphenyl ethers (PBDEs) are among most ubiquitous compounds to be found in indoor environment and ingestion of household dust is considered an important route of exposure to PBDEs, especially in toddlers and young children. The present work reported concentration levels of PBDE congeners (PBDE-28, -47, -99, -100, -153, -154, -183 and -209) in hair and dust samples from selected households from Northern Poland. The...
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Chromium‑based metal organic framework for pipette tip micro‑solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples
PublikacjaAbstract Background A chromium-based metal organic framework was synthesized and employed as an efficient sorbent for pipette tip micro-solid phase extraction and preconcentration of parabens from wastewater and shampoo samples up to sub-ppb level before their spectrophotometric analysis. Results Factors affecting preconcentration including volume and type of solvent, amount of sorbent, number of extraction, and volume and pH of...
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Increased concentration of Taq DNA polymerase as a solution for GC-rich templates from clinical and environmental samples
PublikacjaDNA polymerase is an enzyme which plays crucial role in replication and DNA repair. It found application in PCR (polymerase chain reaction) where catalyses process of in vitro DNA synthesis. To meet the demands posed by mod- ern diagnostic, molecular biology or genetic engineering it is necessary to improve DNA polymerases to obtain new or better features useful in these fields. So far implemented modifications in majority are...
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Evaluation of Langmuir and Freundlich Isotherms for Removal of Cephalexin and Tetracycline Antibiotics By Sistan Sand from Water and Wastewater Samples
PublikacjaIn this research, Sistan sand was used as a natural and inexpensive sorbent for removal of cephalexin and tetracycline antibiotics from water and wastewater samples. For a concentration 60.0 mg L-1 of cephalexin, optimum removal conditions were: pH of the sample 3.0, adsorbent amount 1.0 g, contact time 20.0 min, added amount of sodium chloride to adjust the ionic strength of the solution 7.0 g L-1. Langmuir isotherm was the best...
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Influence of Soft Soil Samples Quality on the Compressibility and Undrained Shear Strength – Seven Lessons Learned From the Vistula Marshlands
PublikacjaThis technical article presents the influence of sample quality on the compressibility parameters and undrained shear strength ( c u ) of soft soils from the Vistula Marshlands. The analysis covers: (1) quality of soft soil according to three criteria: void ratio (Δ e / e 0 index), volumetric strain (Δ ɛ v ) and C r / C c ratio; (2) influence of storage time on quality; (3) influence of sample quality on undrained shear strength...
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Application of dispersive liquid - liquid microextraction for determination of pesticides from various chemical groups in water samples
PublikacjaPesticides are a global risk because they move with the wind, rain and sea currents from other regions, which makes getting to places which were never used before. Their presence was detected in all types of water circulating in the ecosystem, which is an easy source of exposure to life and health of all living organisms. Currently, it is considered one of the most dangerous and toxic pollutants, which fate and function is still...
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Magnetic deep eutectic solvents as efficient media for extraction of furfural and 5-hydroxymethylfurfural from aqueous samples
PublikacjaThe extraction of furfural (FF) and 5-hydroxymethylfurfural (HMF) from hydrolysates is currently one of the main challenges in bio-refinery. In this work, the separation of FF and HMF from the aqueous phase was carried out using a new type of green solvents – Magnetic Deep Eutectic Solvents (MDES). A conductor-like screening model for realistic solvents (COSMO-RS) was used for the preselection of 400 MDES. MDES which exhibit the...