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Właściwości i potencjalne zastosowania azobenzokoron: hydroksyazobenzokorony
PublikacjaW rozprawie doktorskiej przedstawiono właściwości oraz metody syntezy azobenzokoron oraz hydroksyazobenzokoron. Opisano również zastosowanie związków makrocyklicznych jako chromojonoforów w czujnikach optycznych. W ramach pracy zbadano wpływ pH, rozpuszczalników oraz obecności jonów na równowagę tautomeryczną wybranych hydroksyazobenzokoron. Zbadano również równowagę kompleksowania jonów metali przez te związki oraz sprawdzono...
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Solubility advantage of sulfanilamide and sulfacetamide in natural deep eutectic systems: experimental and theoretical investigations
PublikacjaObjective: The aim of this study was to explore the possibility of using natural deep eutectic solvents (NADES) as solvation media for enhancement of solubility of sulfonamides, as well as gaining some thermodynamic characteristics of the analyzed systems. Significance: Low solubility of many active pharmaceutical ingredients is a well-recognized difficulty in pharmaceutical industry, hence the need for different strategies addressing...
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Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds
PublikacjaOne of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits....
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The role of water in deep eutectic solvent-base extraction
PublikacjaDeep eutectic solvents (DESs) are currently being used in different sectors, such as electrochemistry, electrodeposition, organic synthesis, nanoparticle preparation, bioactive compound separation, etc. Their use in analytical chemistry has only recently begun to expand. Despite the publication of a sufficient number of DES-based analytical extraction procedures, some details, such as interaction of DESwith the sample and target...
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Troubleshooting of the determination of bisphenol A at ultra-trace levels by liquid chromatography and tandem mass spectrometry
PublikacjaDetermination of trace amounts of bisphenol A (BPA) may cause problems mainly related to the presence of BPA in solvents (even in LC-MS grade), laboratory vessels, and plastic equipment used for sample preparation. Variable and sometimes significant amounts of BPA present in the background cause problems in obtaining good repeatability of measurements at the ultra-trace levels. Such observations (i.e., poor repeatability of results)...
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Determination of impurities in pharmaceutical products using LC-MS
PublikacjaPharmaceutical products can be contaminated by residues of solvents, reagents (used for the synthesis) or degradation products. Impurities in drug may pose a risk to human health and life, therefore analysis and identification of impurities in pharmaceutical products is veryimportant and inevitable.High performance liquid chromatography coupled with mass spectrometry (MS) is very useful technique for identification impurities in...
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Interplay of hydrogen bonding and aryl-perfluoroaryl interactions in construction of supramolecular aggregates
PublikacjaThe stacking between aryl and perfluoroaryl units is an important class of the aromatic – aromatic interactions that has attracted rapidly growing interest in recent years. Continuing interest of our group in this subject it had been prepared three new complexes of pentafluorobenzoic acid with benzyl alcohol, 4-methylbenzyl alcohol and 4-tert-butylbenzyl alcohol and in the next step investigated their self-assembly modes by...
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Polyurethane-based aerogels: Preparation, properties, and applications
PublikacjaPolyurethane aerogels (PUAs) are interesting materials because of their high porosity, low density, and low thermal conductivity, which result in their application as thermal insulations. PUAs are mainly synthesized using di- and polyisocyanates, diols or polyols, catalysts (tertiary amines and organometallic), and solvents (which are used as reaction medium, purifying of obtained semiproducts). Preparation procedure involves several...
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Visualizing spatially decomposed intermolecular correlations in the infrared spectra of aprotic liquids
PublikacjaInfrared (IR) spectroscopy is commonly used to study intermolecular interactions in the liquid phase, including solvation phenomena. On the other hand, ab initio molecular dynamics (AIMD) simulations offer the possibility to obtain IR spectra from first principles. Surpassing the experiment, AIMD simulations can deliver additional information on the spatial intermolecular correlations underlying the IR spectrum of the liquid. Although...
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Main complications connected with detection, identification and determination of trace organic constituents in complex matrix samples
PublikacjaIt is well known that some problems with the determination of organic analytes at trace level can occur. This issue is connected with contamination during each stage of the analytical procedure from sampling to sample preparation up to chromatographic analysis, which often leads to false-positive or overestimated results. Another problem associated with determination of analytes occurs at trace- and ultra-trace level is a background...
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Developments in Green Chromatography
PublikacjaGreen analytical chemistry is a widely recognized concept that has led to the development of new analytical methods with reduced environmental impact and minimized analyst occupational exposure. Achievements include the development of microextraction, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) techniques. Research towards greener separation processes focuses on the elimination of toxic solvents...
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Chemometrics approaches to green analytical chemistry procedure development
PublikacjaChemometric tools are widely used in analytical chemistry for the reduction of data dimensionality, grouping of variables and processing of analytical signals. They have also the potential to be applied in analytical procedure development with the aim of minimizing the procedure’s environmental impact. The design of experiment gives the possibility to obtain much better information on the system response than in case of “changing...
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Polymeric porous membranes as solid support and protective material in microextraction processes: A review
PublikacjaPolymeric porous membranes have proven to be a versatile and efficient material for microextraction processes. In analytical practice, they are used both as a solid support and as a protective medium for improved sample preparation in various analytical applications. Polymeric porous membranes offer unique advantages in microextraction due to their large surface area and controllable pore size, eliminating interfering effects from...
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Remarks on use of the term “deep eutectic solvent” in analytical chemistry
PublikacjaAbout 20 years ago, Abbott and co-workers researched new solvents that were based on mixtures of choline chloride with urea and carboxylic acids and that were liquid at ambient temperature. The term “deep eutectic solvent” (DES) was later adopted for similar mixtures. As DESs have a number of interesting features, they quickly attracted the attention of researchers and found application in various branches of chemical and materials...
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AGREEprep – Analytical greenness metric for sample preparation
PublikacjaThis work proposes for the first time, a metric tool that gives prominence to sample preparation. The developed metric (termed AGREEprep) was based on 10 categories of impact that were recalculated to 0 e1 scale sub-scores, and then used to calculate the final assessment score. The criteria of assessment evaluated, among others, the choice and use of solvents, materials and reagents, waste generation, energy consumption, sample...
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Green analytical chemistry : theory and practice
PublikacjaThis tutorial review summarises the current state of green analytical chemistry with special emphasis on environmentally friendly sample preparation techniques. Green analytical chemistry is a part of the sustainable development concept; its history and origins are described. Miniaturisation of analytical devices and shortening the time elapsing between performing analysis and obtaining reliable analytical results are important...
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Programmed metalloporphyrins for self-assembly within light-harvesting stacks: 5,15-dicyano-10,20-bis(3,5-di-tert-butylphenyl)-porphyrinato zinc(II) and its push-pull 15-N,N-dialkylamino-5-cyano congeners obtained by a facile direct amination.
PublikacjaThe title dicyano compound was synthesized via cyanation and it self-assembles in nonpolar solvents giving red-shifted and broad absorption maxima just as the bacteriochlorophylls which are encountered in the light-harvesting organelles of early photosynthetic bacteria. In the crystal, stacks are formed through a hierarchic combination of π-stacking and a CNZn electrostatic interaction. Push−pull 15-N,N-dialkylamino-5-cyano congeners...
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Excess molar volume and viscosity deviation for binary mixtures of gamma-butyrolactone with dimethyl sulfoxide
PublikacjaThe densities of binary liquid mixtures of dimethyl sulfoxide and gamma-butyrolactone at (293.15, 298.15, 303.15 and 313.15) K and viscosity at T=298.15 K have been measured at atmospheric pressure over theentire range of concentration. From these data the excess molar volumes VE at (293.15, 298.15, 303.15 and 313.15) K and the viscosity deviation, the excess entropy, and the excess Gibbs energy of activation for viscous flow at...
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Computational modeling of molecularly imprinted polymers as a green approach to the development of novel analytical sorbents
PublikacjaThe development of novel molecularly imprinted polymers (MIP) sorbents for specific chemical compounds require a lot of tedious and time-consuming laboratory work. Significant quantities of solvents and reagents are consumed in the course of the verification of appropriate configurations of polymerization reagents. Implementation of molecular modeling in the MIP sorbent development process appears to provide a solution to this...
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Diethyl carbonate as a green extraction solvent for chlorophenol determination with dispersive liquid–liquid microextraction
PublikacjaThe principles of green analytical chemistry indicate that the search for greener organic solvents for extraction applications is crucial. In this study diethyl carbonate (DEC) is proved to be a green solvent, as it is relatively nontoxic, obtainable from renewable resources and biodegradable. Here it is applied as an extraction solvent for chlorophenol determination in water samples with dispersive liquid–liquid microextraction....
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Synthesis and polymerisation techniques of molecularly imprinted polymers
PublikacjaMolecularly Imprinted Polymers (MIPs) are materials that has been processed using the molecular imprinting technique which permit to obtain well-defined three-dimensional cavities, with affinity to a template molecule, in the polymer matrix. Technology involves three strategies, i.e., covalent, non-covalent and semi-covalent approach, but the most popular is non-covalent approach. The most important components for the synthesis...
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A method for a comprehensive lipidomic analysis of flaxseed (Linum usitatissimum) with the use of LC–Q-TOF-MS and dispersive micro-solid-phase (μDSPE) extraction
PublikacjaFlaxseed (FS) is one of the richest sources of α-linolenic acid oil and lignans, and it is suggested that the consumption of flaxseed may contribute to the prevention of certain chronic diseases such as many types of cancer, diabetes, cardiovascular diseases and cerebrovascular stroke. Here, we demonstrate a new method for comprehensive FS lipidome profiling with the use of LC–Q-TOF-MS and dispersive micro-solid-phase extraction....
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Metrics for green analytical chemistry
PublikacjaGreen analytical chemistry, although not being a new concept, does not have a greenness metrics system. Green chemistry metrics are not suitable for analytical procedure assessment because they often refer to the mass of the product. Some efforts have been made to develop suitable metrics for analytical chemistry. Some are simple to use but do not cover all aspects of analytical methods’ environmental impact. Others are more comprehensive...
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Copper-based 2D-coordination polymer as catalyst for allylation of aldehydes
PublikacjaA copper-tartrate, [Cu2(Tart)2(H2O)2]·4H2O, was synthesized at room temperature in aqueous media using copper chloride and D-tartaric acid. The compound crystallizes in the monoclinic system P21 space group and was characterized by infrared spectroscopy, thermogravimetry, X-ray powder diffraction and the results are in good agreement with the single crystal...
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Solubilization of keratins and functional properties of their isolates and hydrolysates
PublikacjaThe keratinous wastes of the textile industry and poultry slaughterhouses may be used as sources of soluble keratins or hydrolysates. This review presents methods for processing raw keratin-based materials into bioproducts with functional and bioactive properties suitable for biomedical, cosmetic, food, and agricultural applications. Soluble keratin can be obtained by thermal treatment in some organic solvents, reduction, or oxidation...
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Understainding solid-phase microextraction: key factors influencing the extraction process and trends in improving the technique
PublikacjaAnalytical chemists are faced with the daunting challenges of accurately monitoring the state of the environment and the processes taking place in it and of determining an enormous range of analytes often present in trace and ultratrace amounts in sample matrixes with complex or variable compositions. Further challenges are presented by the need to introduce new methodologies into current analytical practice and equipment to comply...
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Morphology control via dual solvent crystallization for high-mobility functionalized pentacene-blend thin film transistors
PublikacjaWe present an approach to improving the performance of solution processed organic semiconductor transistors based on a dual solvent system. We here apply this to a blend containing the π-conjugated small molecule 6,13 bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) and polystyrene, which acts as an inert binder. Using a semiconductor-binder solution of two solvents, where the main solvent is a better solvent of the small...
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Pharmaceutical and forensic drug applications of chiral supercritical fluid chromatography
PublikacjaTHE SUPERCRITICAL FLUID IS AN EXCELLENT CHOICE AS THE CHROMATOGRAPHIC MOBILE PHASE BECAUSE IT ALLOWS RAPID SEPARATION WITH HIGH EFFICIENCY AND APPLICATIONS INVOLVING ENANTIORESOLUTION ARE COMMON. SUPERCRITICAL FLUID CHROMATOGRAPHY (SFC) IS INCREASINGLY USED FOR ANALYTICAL, SEMI-PREPARATIVE AND PREPARATIVE PURIFICATION OF CHIRAL COMPOUNDS, INCLUDING PRODUCTION OF ENANTIOMERS THAT ARE MAINLY ENCOUNTERED DURING DRUG DEVELOPMENT. SFC...
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Synteza, struktura chemiczna i właściwości bezizocyjanianowych poliuretanów otrzymywanych z wykorzystaniem CO2 oraz surowców pochodzenia naturalnego.
PublikacjaZ uwagi na wciąż rosnącą świadomość proekologiczną, politykę zrównoważonego rozwoju, a także nurt zielonej chemii wiodącym trendem w przemyśle tworzyw sztucznych jest poszukiwanie alternatywnych metod otrzymywania materiałów polimerowych. Komercyjnie poliuretany otrzymywane są w wyniku reakcji poliaddycji di- lub poliizocyjanianów z poliolami i małocząsteczkowymi przedłużaczami łańcucha. Z uwagi na niekorzystne właściwości diizocyjanianów,...
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Deep eutectic solvent-based shaking-assisted extraction for determination of bioactive compounds from Norway spruce roots
PublikacjaPolyphenolic compounds play an essential role in plant growth, reproduction, and defense mechanisms against pathogens and environmental stresses. Extracting these compounds is the initial step in assessing phytochemical changes, where the choice of extraction method significantly influences the extracted analytes. However, due to environmental factors, analyzing numerous samples is necessary for statistically significant results,...
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Ionic liquids for nano- and microstructures preparation. Part 2: Application in synthesis
PublikacjaIonic liquids (ILs) are widely applied to prepare metal nanoparticles and 3D semiconductor microparticles. Generally, they serve as a structuring agent or reaction medium (solvent), however it was also demonstrated that ILs can also play a role of a co-solvent, metal precursor, reducing as well as surface modifying agent. The crucial role and possible types of interactions between ILs and growing particles have been presented in...
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Ionic liquids in extraction techniques: Determination of pesticides in food and environmental samples
PublikacjaThe intensive use of pesticides in agricultural practices has promoted the appearance of environmentaland public health problems. Due to that, scientists face challenges with developing simple, fast, sensitive,selective, and low-cost methods dedicated to determining pesticide residues in food and environmentalsamples. Following thefifth principle of Green Analytical Chemistry, chemists are searching for greeneralternatives for...
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Merging Proline:Xylitol Eutectic Solvent in Crosslinked Chitosan Pervaporation Membranes for Enhanced Water Permeation in Dehydrating Ethanol
PublikacjaThe scope of this research aims at merging a new deep eutectic mixture (DES) into a biopolymer-based membrane for a pervaporation application in dehydrating ethanol. Herein, an L-proline:xylitol (at 5:1) eutectic mixture was successfully synthesized and blended with chitosan (CS). A complete characterization of the hybrid membranes, in terms of morphology, solvent uptake, and hydrophilicity, has been conducted. As part of their...
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Comparison of different extraction techniques of polychlorinated biphenyls from sediments samples.
PublikacjaIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. Main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sedimentreference material (METRANAL 2) with the use of different solvents (dichloromethane, hexsane, and toluene); the process...
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Comparison of the Efficiency of Hetero- and Homogeneous Catalysts in Cellulose Liquefaction
PublikacjaBiomass liquefaction is a well-known and extensively described process. Hydrothermal processes are well understood and can be used in the fuel industry. The use of organic solvents can result in full-fledged products for use in the synthesis of polyurethanes. The plastics industry, including polyurethanes, is targeting new, more environmentally friendly solutions. One of these is the replacement of petrochemical polyols with compounds...
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Deep eutectic solvent (DES) with silver nanoparticles (Ag-NPs) based assay for analysis of lead (II) in edible oils
PublikacjaThis paper presents an application of silver nanoparticles impregnated by Deep Eutectic Solvents (DES) as ultrasonication aided microextraction system for lead (II) determination in edible oils. The paper presents a systematic optimization of method parameters and examples of its application for analysis of real samples. Maximum recovery for lead (II) extraction was obtained for choline chloride and phenol with a 1:2 molar ratio....
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Progress in development of molecularly imprinted polymers as sorbents for sample preparation
PublikacjaSample preparation has been one of the most often investigated steps in analytical procedures.These investigations are focused on problems such as isolation of analytes from the sample matrix, matrix implification, analyte enrichment to the level above the detection limit of the instrumentation used, and the removal of interfering species to improve the final determination. Techniques based on solid (adsorption) and pseudo liquid...
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Transport properties of aqueous ionic liquid microemulsions: influence of the anion type and presence of the cosurfactant
PublikacjaTransport properties, viz. specific conductivity, dynamic viscosity and apparent diffusion coefficients, were measured as a function of water content in aqueous ionic liquid microemulsions containing 1-butyl-3- methylimidazolium hexafluorophosphate, [BMIM][PF6] and bis(trifluoromethanesulphonyl)imide, [BMIM][Tf2N], stabilized by the nonionic surfactant TX-100, or its mixture with a cosurfactant, i.e. butanol. The investigation covered...
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Ultrasound assisted extraction
PublikacjaThe use of green and sustainable extraction techniques is very popular topic in the multidisciplinary area of chemistry, biology and technology. There is no doubt that extraction constitutes a very important step of analytical procedures of separation, detection, identification and determination of wide spectrum analytes from samples characterized by complex and very often nonhomogeneous composition of matrix. Traditional techniques...
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Porosity and swelling properties of novel polyurethane–ascorbic acid scaffolds prepared by different procedures for potential use in bone tissue engineering
PublikacjaIn this work, a novel polyurethane (PU) system based on poly(ethylene-butylene) adipate diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol, and ascorbic acid was used to prepare scaffolds with potential applications in bone tissue engineering. Two fabrication methods to obtain porous materials were chosen: phase separation (PS)/salt particle leaching (PL) and solvent casting (SC)/salt PL. The calculated porosity demonstrated...
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Organic semiconductor rubrene thin films deposited by pulsed laser evaporation of solidified solutions
PublikacjaOrganic semiconductor rubrene (C42H28) belongs to most preferred spintronic materials because of the high charge carrier mobility up to 40 cm2(V·s)-1. However, the fabrication of a defect-free, polycrystalline rubrene for spintronic applications represents a difficult task. We report preparation and properties of rubrene thin films deposited by pulsed laser evaporation of solidified solutions. Samples of rubrene dissolved in aromatic...
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The Sonocatalytic Activation of Persulfates on Iron Nanoparticle Decorated Zeolite for the Degradation of 1,4-Dioxane in Aquatic Environments
PublikacjaIn the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a solvent as well as a stabilizing agent for chlorinated solvents. Due to its high miscibility, dioxane is a ubiquitous water contaminant. This study investigates the effectiveness of catalyst- and ultrasound (US)-assisted persulfate (PS) activation with regard to degrading dioxane. As a first step, a composite catalyst was prepared using...
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Sustainable synthesis of cyclic carbonates from bio‐based polyether polyol: the structure characterization, rheological behaviour and thermal properties
PublikacjaThe cycloaddition of CO2 to epoxides represents a green efficient method to form bis(cyclic carbonate)s. The main purpose of the work reported in this paper was to examine the effect of the gas flow rate (20, 40, 60 and 100 mL min–1) during carbonation on the conversion yield, chemical structure, rheological behaviour and thermal properties of the prepared compounds. A series of new bis(cyclic carbonate)s was obtained from bio‐based...
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Applicability of phenolic acids as effective enhancers of cocrystals solubility of methylxanthines
PublikacjaApplicability of phenolic acids as potential cocrystal formers for methylxanthine derivatives was analyzed both in terms of cocrystallization probabilities and solubility advantage. The cocrystal formation abilities were evaluated using mixing enthalpy estimated within the conductor like screening model for real solvents (COSMO-RS) framework. The solubility improvement of potential cocrystals was estimated by formulation of the...
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Magnetic superhydrophobic melamine sponges for crude oil removal from water
PublikacjaThis paper proposes the preparation of a new sorbent material based on melamine sponges (MS) with superhydrophobic, superoleophilic, and magnetic properties. This study involved impregnating the surface of commercially available MS with eco-friendly deep eutectic solvents (DES) and Fe3O4 nanoparticles. The DES selection was based on the screening of 105 eutectic mixtures using COSMO-RS modeling. Other parameters affecting the efficiency...
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Morphology control through the synthesis of metal-organic frameworks
PublikacjaDesignable morphology and predictable properties are the most challenging goals in material engineering. Features such as shape, size, porosity, agglomeration ratio significantly affect the final properties of metal- organic frameworks (MOFs) and can be regulated throughout synthesis parameters but require a deep under- standing of the mechanisms of MOFs formation. Herein, we systematically summarize the effects of the indi- vidual...
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An air-assisted dispersive liquid phase microextraction method based on a hydrophobic magnetic deep eutectic solvent for the extraction and preconcentration of melamine from milk and milk-based products
PublikacjaIn the current research, a fast and sustainable air-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction followed by UV–Vis spectrophotometry measurements was optimized for the extraction and determination of melamine in milk and milk-based products. The central composite design was applied for the optimization of factors affecting the recovery of melamine. Quantitative extraction of...
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Mangiferin: A comprehensive review on its extraction, purification and uses in food systems
PublikacjaWith the target of fabricating healthier products, food manufacturing companies look for natural-based nutraceuticals that can potentially improve the physicochemical properties of food systems while being nutritive to the consumer and providing additional health benefits (biological activities). In this regard, Mangiferin joins all these requirements as a potential nutraceutical, which is typically contained in Mangifera indica...
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A closer look at how the dispersive liquid–liquid microextraction method works. Investigation of the effect of solvent mixture composition on the quality and stability of the cloudy state
PublikacjaThe dispersive liquid–liquid microextraction (DLLME) is one of the most popular miniaturized extraction procedures. In this paper, the degree of dispersion and dispersion stability were studied with the aim to assess the correlations of these parameters with efficiency for the selected analytical application. The dependence between the degree of dispersion (cloudy state quality) and its stability obtained by various emulsification...
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A review: Fabrication of porous polyurethane scaffolds
PublikacjaThe aim of tissue engineering is the fabrication of three-dimensional scaffolds that can be used for the reconstruction and regeneration of damaged or deformed tissues and organs. A wide variety of techniques have been developed to create either fibrous or porous scaffolds from polymers, metals, composite materials and ceramics. However, the most promising materials are biodegradable polymers due to their comprehensive mechanical...