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Sample preparation techniques for determination of pesticide residues in food samples
PublikacjaPesticides 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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Hydrophobic deep eutectic solvents in microextraction techniques–A review
PublikacjaOver the past decade, deep eutectic solvents (DES) have been widely studied and applied in sample preparation techniques. Until recently, most of the synthesized DES were hydrophilic, which prevented their use in the extraction of aqueous samples. However, after 2015 studies on the synthesis and application of hydrophobic deep eutectic solvents (HDES) has rapidly expanded. Due to unique properties of HDES i.e. density, viscosity,...
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Characterization of novel trehalose synthase from Deinococcus geothermalis.
PublikacjaThe method of trehalose extraction from yeast or othernatural sources is unsuitable for industrial production becauseof its low yield and high cost. Thus, the trehalose synthesizingenzyme systems that originated from a few microorganisms have been investigated.
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Application of gas chromatography to the analysis of spirit-based alcoholic beverages
PublikacjaSpirit-based beverages are alcoholic drinks, which production processes are dependent on the type and origin of raw materials. The composition of this complex matrix is difficult to analyze and scientists commonly choose a gas chromatography techniques for this reason. With a wide selection of extraction methods and detectors it is possible to provide qualitative and quantitative analysis for many chemical compounds with a various...
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Diverse roles, advantages and importance of deep eutectic solvents application in solid and liquid-phase microextraction techniques – A review
PublikacjaDeep eutectic solvents (DESs) are an emerging class of promising green solvents used as an alternative to traditional organic solvents in various scientific fields. The high biodegradability, biocompatibility, eco-friendliness, tunable properties, and presence of active groups in DESs make them the preferred solvent in a variety of solid- and liquid-phase microextraction techniques. Aside from these benefits, the use of DESs in...
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Shoreline Extraction Based on LiDAR Data Obtained Using an USV
PublikacjaThis article explores the use of Light Detection And Ranging (LiDAR) derived point clouds to extract the shoreline of the Lake Kłodno (Poland), based on their geometry properties. The data collection was performed using the Velodyne VLP‐16 laser scanner, which was mounted on the HydroDron Unmanned Surface Vehicle (USV). A modified version of the shoreline extraction method proposed by Xu et al. was employed, comprising of the following...
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Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy
PublikacjaAlcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures...
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Rapid Characterization of the Human Breast Milk Lipidome Using a Solid-Phase Microextraction and Liquid Chromatography-Mass Spectrometry-Based Approach.
PublikacjaHuman breast milk (HBM) is a biofluid consisting of various biomolecules such as proteins, lipids, carbohydrates, minerals and bioactive substances. Due to its unique and complex composition, HBM provides not only nutritional components required for the growth of the infant, but also additional protection against infections. Global insight into the composition of HBM is crucial to understanding the health benefits infants receive...
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Deep eutectic solvents with solid supports used in microextraction processes applied for endocrine-disrupting chemicals
PublikacjaThe determination of endocrine-disrupting chemicals (EDCs) has become one of the biggest challenges in Analytical Chemistry. Due to the low concentration of these compounds in different kinds of samples, it becomes necessary to employ efficient sample preparation methods and sensitive measurement techniques to achieve low limits of detection. This issue becomes even more struggling when the principles of the Green Analytical Chemistry...
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Polychlorinated biphenyls (PCBs) and polychlorodibenzo-p-dioxins (PCDDs) determination in disposable baby diapers with the application of natural deep eutectic solvent
PublikacjaIn this work a new method involving solvent extraction of porous membrane-packed solid samples (SE-PMSS) coupled to gas chromatography-mass spectrometry (GC–MS) has been developed for the determination of six polychlorinated biphenyls (PCBs) and five polychlorodibenzo-p-dioxines (PCDDs) in disposable baby diapers. In that aim, a terpenoid-based natural deep eutectic solvent (NADES) composed of carvone and camphor in a 1:1 M ratio...
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Systematic Literature Review for Emotion Recognition from EEG Signals
PublikacjaResearchers have recently become increasingly interested in recognizing emotions from electroencephalogram (EEG) signals and many studies utilizing different approaches have been conducted in this field. For the purposes of this work, we performed a systematic literature review including over 40 articles in order to identify the best set of methods for the emotion recognition problem. Our work collects information about the most...
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Systematic Literature Review for Emotion Recognition from EEG Signals
PublikacjaResearchers have recently become increasingly interested in recognizing emotions from electroencephalogram (EEG) signals and many studies utilizing different approaches have been conducted in this field. For the purposes of this work, we performed a systematic literature review including over 40 articles in order to identify the best set of methods for the emotion recognition problem. Our work collects information about the most...
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Music Information Retrieval – Soft Computing versus Statistics . Wyszukiwanie informacji muzycznej - algorytmy uczące versus metody statystyczne
PublikacjaMusic Information Retrieval (MIR) is an interdisciplinary research area that covers automated extraction of information from audio signals, music databases and services enabling the indexed information searching. In the early stages the primary focus of MIR was on music information through Query-by-Humming (QBH) applications, i.e. on identifying a piece of music by singing (singing/whistling), while more advanced implementations...
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Discovering patterns of Web Page Visits from Associaton Rules Viewpoint
PublikacjaThe popularity of the Internet results from the almost unlimited resources of information stored in it. At the same time, Internet portals have become a widespread source of information and note very large number of visits. The list of web pages opened by users is stored in web servers' log files. Extraction of knowledge on the navigation paths of users has become carefully analyzed problem. Currently, there are a number of algorithms...
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublikacjaThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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Modern trends in solid phase extraction: New sorbent media
PublikacjaBased on the recently published literature, this review provides an update of the most important features and application of formats and devices employed in solid phase extraction (SPE). Special attention was paid on new trapping media proposed in SPE prior the chromatography analysis, based on the use of nanostructured materials, including carbon nanomaterials, electrospun nanofibers, dendrimes and magnetic nanoparticles, molecular...
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Natural sweeteners: Sources, extraction and current uses in foods and food industries
PublikacjaFood producers have leaned towards alternative natural and synthetic sweeteners in food formulations to satisfy market demands. Even so, several synthetic sweeteners (e.g., aspartame, saccharin, sucralose) are becoming less popular due to health-related concerns, lower nutritional values, and controversies around their safety. Conversely, natural sweeteners confer favourable customer perceptions due to their association to a healthier...
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Application of ultrasound-assisted solvent extraction of porous membrane packed liquid samples for polyphenols determination in wine samples
PublikacjaPolyphenols play a crucial role in a proper human health maintenance as well as their presence very often correspond to the quality assessment of producs like wine. Thus, their monitoring is of high interest. However, as they occur in a complex matrices their extraction is very often necessary prior the analysis. Herein, a new ultrasound-assisted solvent extraction of porous membrane packed liquid sample technique has been optimized...
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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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Determination of phenylbutazone, sulfamethazine, carbendazim and linuron using a novel pine bark biosorbent for solid-phase extraction (SPE) with high-performance liquid chromatography (HPLC)
PublikacjaThe paper presents a novel pine bark based biosorbent for solid-phase extraction (SPE). The morphology and composition of the pine bark were characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The biosorbent was used for the preparation of wastewater for the determination of phenylbutazone, sulfamethazine, carbendazim, and linuron by high performance liquid chromatography with...
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Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization
PublikacjaA novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatisation in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of released from esterified forms analytes from water phase and dilution solvent for solid PBA – derivatisation agent. It is a noteworthy...
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Determination of fuel combustion product in airport runoff water samples using liquid–liquid extraction with gas chromatography–spectrometry
PublikacjaDetermination of xenobiotics in samples of airport runoff water is both a complex and indispensable task due to an increasing threat resulting from the activities of numerous airports. The aim of this study was to develop, optimize, and validate a procedure based on liquid–liquid extraction (LLE) coupled with gas chromatography–mass spectrometry (GC–MS) for the determination of polycyclic aromatic hydrocarbons (PAHs). So far, no...
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The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry
PublikacjaIn this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hy- drocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical chal- lenge to analytical...
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Challenges in determination of pesticides from various chemical groups in fruits and vegetables applying QuEChERS method
PublikacjaPesticides are a large group of compounds with different physical and chemical properties, which place some of them among the most toxic, environmentally stable, and mobile substances. Nevertheless, their number, use, and application are continuously expanding. A consequence of their use is the possible presence of residues in treated food products. To protect consumers from exposure to unacceptable levels of pesticides Maximum...
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Identification and characterization of the Indian Yellow dyestuff and its degradation products in historical oil paint tube by liquid chromatography mass spectrometry
PublikacjaAn analytical protocol for identification of dyes using reversed phase liquid chromatography-mass spectrometry with atmospheric pressure electrospray ionization (LC-ESI/MS) is presented. The developed method has been successfully applied in identification of euxanthic acid and euxanthone, the main components of the Indian Yellow dye in a historical oil paint tube produced by Richard Ain`es, a recognizable French company supplying...
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Miniaturized solid phase extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 2
PublikacjaDetermination of pollutants present in environmental samples at a low concentration level very often requires the analytical protocol that includes analytes isolation and/or enrichment prior to the final quantification. Miniaturized SPE offers an interesting alternative to LLE. Nowadays, many types of sorbents are available and can be used as selective materials for extraction of varied analytes in different kinds of samples. The...
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Role of distillation in determination of SCFAs in samples of different origin
PublikacjaShort-chain fatty acids (SCFAs) are very volatile compounds and choosing an appropriate isolation and enrichement technique is a key to their determination. Distillation is one of methods which can be applied. There are many types of distillation. The simplest ones are direct, steam and fractional distillation, but they are not used very often and have some drawbacks. However, many modifications of basic distillation have been...
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Analyzing the Effectiveness of the Brain–Computer Interface for Task Discerning Based on Machine Learning
PublikacjaThe aim of the study is to compare electroencephalographic (EEG) signal feature extraction methods in the context of the effectiveness of the classification of brain activities. For classification, electroencephalographic signals were obtained using an EEG device from 17 subjects in three mental states (relaxation, excitation, and solving logical task). Blind source separation employing independent component analysis (ICA) was...
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Liquid–phase microextraction: A review of reviews
PublikacjaSample preparation is an important step in chemical analysis. It is generally done to deal with problems associated with the nature of the matrix, low analyte concentrations in real samples or analyte features incompatible with the instrumentation. Classical methods of extraction consume large volumes of hazardous solvents and other reagents and are not in line with the recent emergence of green analytical chemistry. Liquid-phase...
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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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Role of Silicon in Counteracting Cadmium Stress in Pea Plants (Pisum sativum L.): Insights Into Cadmium Binding Mechanisms and Pectin Methylesterase Activity
PublikacjaPurpose: The aim of this study was to investigate the role of silicon (Si) in counteracting a cadmium (Cd) stress to pea plants (Pisum sativum L.) and to identify the mechanism by which Cd is bound within pea roots. Methods: These goals were achieved through (i) a histochemical study of Cd localization in pea roots, (ii) spectrophotometric determination of pectin content and the activity...
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Geochemical fractionation of organic matter in the Jurassic-Cretaceous Vaca Muerta shale, Argentina
PublikacjaSeveral studies have indicated the presence of more than one generation of bitumen that could be isolated from rocks through sequential extraction or after demineralization or both. Nabbefeld et al. (2010a) and Holman et al. (2012, 2014) termed bitumen obtained after solvent extraction from the undigested rock as “Bitumen I" and that obtained by extraction after demineralization of rock as “Bitumen II.” The occurrence of different...
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Isoprostanes-Biomarkers of Lipid Peroxidation: Their Utility in Evaluating Oxidative Stress and Analysis
PublikacjaIsoprostanes (IsoPs) are key biomarkers for investigating the role of free radical generation in the pathogenesis of human disorders. To solve IsoPs-related problems with regard to isoprostanes, analytical tools are required. This paper reviews the problems and trends in this field focusing on the methodology for assaying biomarkers in exhaled breath condensate (EBC) samples. A large amount of work has been done in the qualitative...
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Solid phase microextraction–comprehensive twodimensional gas chromatography–time-of-flight mass spectrometry: a new tool for determining PAHs in airport runoff water samples
Publikacjafundamental aspect of airport operations is the pollution caused by airport runoff waters. Polycyclic aromatic hydrocarbons (PAHs) are one of the most important groups of xenobiotics which are commonly found in runoff water originating from airports. Only very limited data on the analysis of airport runoff water have been published until now. Therefore, a reliable and accurate analytical method based on headspace solid-phase microextraction...
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Alginate-based sorbents in miniaturized solid phase extraction techniques - Step towards greenness sample preparation
PublikacjaIn response to growing concerns about environmental degradation, one of the main areas of research activity in recent years has been to make sample preparation methods more sustainable and eco-friendly. The increasing greenness of this step can be achieved by minimizing the usage of reagents, automating individual stages, saving energy and time, and using non-toxic, biodegradable substances. Therefore, the use of natural materials...
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Arabinoxylans: A review on protocols for their recovery, functionalities and roles in food formulations
PublikacjaArabinoxylans (AXs) are compounds with high nutritional value and applicability, including prebiotics or supplementary ingredients, in food manufacturing industries. Unfortunately, the recovery of AXs may require advanced separation and integrated strategies. Here, an analysis of the emerging techniques to extract AXs from cereals and their by-products is discussed. This review covers distinct methods implemented over the last...
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A solid phase extraction–ion chromatography with conductivity detection procedure for determining cationic surfactants in surface water samples
PublikacjaA new analytical procedure for the simultaneous determination of individual cationic surfactants (alkyl benzyl dimethyl ammonium chlorides) in surface water samples has been developed. We describe this methodology for the first time: it involves the application of solid phase extraction (SPE – for sample preparation) coupled with ion chromatography–conductivity detection (IC-CD – for the final determination). Mean recoveries of...
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Chitin and derivative chitosan-based structures — Preparation strategies aided by deep eutectic solvents: A review
PublikacjaThe high molecular weight of chitin, as a biopolymer, challenges its extraction due to its insolubility in the solvents. Also, chitosan, as the N-deacetylated form of chitin, can be employed as a primary material for different industries. The low mechanical stability and poor plasticity of chitosan films, as a result of incompatible interaction between chitosan and the used solvent, have limited its industrialization. Deep eutectic...
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Ferrofluids based analytical extractions and evaluation of their greenness
PublikacjaFerrofluids are stable dispersions of magnetic nanoparticles in a carrier liquid. They have attracted considerable attention in analytical extractions as they combine fluid-like properties with magnetic character, providing magnetic control over the extraction process. The synthesis of ferrofluids is very straightforward, and it generally involves the preparation of magnetic nanoparticles, their coating, and then mixing in a suitable...
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New analytical sample preparation techniques in food flavour analysis
PublikacjaIn this chapter sample preparation techniques were broadly characterized and their applications in field of food analysis were presented. Usefulness of three extraction methods: SPME, SAFE and SDE for isolation of aroma compounds from complex food matrices was compared. Additionally, requirements for sample preparation methods using in food flavour analysis were detailed.
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Discovery of Stylistic Patterns in Business Process Textual Descriptions: IT Ticket Case
PublikacjaGrowing IT complexity and related problems, which are reflected in IT tickets,create a need for new qualitative approaches. The goal isto automate the extraction of main topics described in tickets in order to provide high quality support for the IT process workers and enablea smooth service delivery to the end user. Present paper proposes a method of knowledge extraction in a form of stylistic patterns in business...
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On Accuracy Modeling of Gas Turbine Cycles by the In-house COM-GAS Code
PublikacjaIn this paper, a comparison of accuracy modeling of gas turbine cycles between the basic (classical) model and the in-house COM-GAS code has been presented. The basic model uses a semi-perfect gas and well known projecting assumption. On the other hand, the computational flow mechanics (CFM) basis on a real gas by using thermodynamic tables. The thermodynamic analysis of thermal cycles, simply gas cycle GT8C and gas turbine cycle...
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Alternative Methods of Preparation of Soluble Keratin from Chicken Feathers
PublikacjaHuge amount of keratinous waste, especially birds’ feathers, demands more value-added application instead of dumping. The present work reports the results of experiments aimed at preparing soluble keratin useful for novel bioproduct formation. The effect of thermo-chemical treatments with various reducing agents, i.e. 2-mercaptoethanol, dithiothreitol, sodium m-bisulphite, and sodium bisulphite, as well as sodium hydroxide, on...
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Comparison of different techniques for extracting Polychlorinated Biphenyls from bottom sediment samples using Isotope Dilution Mass Spectrometry
PublikacjaIn this work, problems that may occur during determination of trace levels of polychlorinated biphenyls in sediment samples are described. The main error sources are connected with extraction of analytes prior to final determination. During model studies, polychlorinated biphenyls have been extracted from sediment reference material (METRANAL 2) with the use of different solvents (dichloromethane, hexane, and toluene); the process...
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Deep eutectic solvents in analytical sample preconcentration Part B: Solid-phase (micro)extraction
PublikacjaOne of the key challenges of modern analytical chemistry is the monitoring of trace amounts of contaminants using sensitive and selective instrumental techniques. Due to the variety and complexity of some samples, it is often necessary to properly prepare a sample and to perform a preconcentration of trace amounts of analytes. In line with the principles of Green Analytical Chemistry (GAC), it is important for an analytical procedure...
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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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The use of Kamienna głowa cabbage species for phytoextraction of zinc and cadmium from the soil
PublikacjaAlthough traditional technologies for cleaning contaminated soils have proven to be efficient, they are usually expensive, labor intensive, and in the case of soil, they produce severe disturbance. Most recently, the use of plants in metal extraction (phytoremediation) has appeared as a promising alternative in the removal of heavy metal excess from soil. Phytoremediation uses of plant for pollutant stabilization, extraction, degradation,...
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Determination of parent and methylated polycyclic aromatic hydrocarbons in water samples by dispersive liquid–liquid microextraction–two dimensional gas chromatography–time-of-flight mass spectrometry
PublikacjaPolycyclic aromatic hydrocarbons (PAHs) are contaminants frequently found in environmental waters. Owing to their toxic effects, it is important to develop analytical methodologies that allow their fast and reliable determination. Dispersive liquid–liquid microextraction (DLLME) allows a quick extraction of analytes with little organic solvent consumption. The best results regarding sample preparation are obtained when 40 mL of...
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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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Optimization of capillary isotachophoretic method for determination of major macroelements in blue honeysuckle berries (Lonicera caerulea L.) and related products
PublikacjaA reliable and repeatable isotachophoretic method for the simultaneous determination of K+, Na+, Ca2+, Mg2+ and ammonium in berries of different blue honeysuckle cultivars was developed. The usefulness of the complex-forming equilibria in determining the cations mentioned above was studied. The addition of 7.5 mM 18-crown-6 and 2 mM α-hydroxyisobutyric acid to sulfuric acid enhanced the separation capacity of the leading electrolyte....