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Search results for: Sampling/extraction%20techniques
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Passive sampling and/or extraction techniques in environmental analysis: a review
PublicationThe current state-of-the-art of passive sampling and/or extraction methods for long-term monitoring of pollutants in different environmental compartments is discussed in this review. Passive dosimeters that have been successfully used to monitor organic and inorganic contaminants in air, water, sediments, and soil are presented. The application of new approaches to the determination of pollutants at the sampling stage is discussed....
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Passive sampling and/or extraction techniquesin environmental analysis: a review
PublicationPrzedstawiono przegląd literaturowy dotyczący pasywnych technik izolacji i wzbogacania analitów z matryc środowiskowych, takich jak powietrze, woda czy gleba. Zwrócono uwagę na rosnącą rolę technik pasywnych w monitoringu środowiskowym oraz zaprezentowano krótki rys historyczny rozwoju tych technik.
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Soxhlet Extraction and New Developments Such as Soxtec in: Comprehansive Sampling and Sample Preparation
PublicationSoxhlet extraction is one of the most popular techniques for extraction of analytes from solid materials. Since its discovery in 1879, the standard Soxhlet technique has been routinely applied in almost every analytical laboratory. Up to this day, Soxhlet extraction technique remains a standard technique to which the performance of modern extraction techniques is compared.Over the years, an intensive research on different modifications...
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Down-Sampling of Large LiDAR Dataset in the Context of Off-Road Objects Extraction
PublicationNowadays, LiDAR (Light Detection and Ranging) is used in many fields, such as transportation. Thanks to the recent technological improvements, the current generation of LiDAR mapping instruments available on the market allows to acquire up to millions of three-dimensional (3D) points per second. On the one hand, such improvements allowed the development of LiDAR-based systems with increased productivity, enabling the quick acquisition...
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Salinity and pH as factors affecting the passive sampling and extraction of pharmaceuticals from water
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Polyethylene glycol-coated solid-phase microextraction fibres for the extraction of polar analytes-A review
PublicationThe article discusses the merits and limitations of commercially available solid-phase microextraction (SPME) fibres and compares them with the new type of extraction coatings, in particular those containing polyethylene glycol as sorbent, as well as the methods of the preparation of the latter. It also analyses their possible application for the extraction of a broad spectrum of analytes, with particular emphasis on the sampling...
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Error analysis of calculating average d-q current components using Regular Sampling and Park transformation in FOC drives
PublicationIn electric drives using voltage source inverters, motor currents contain ripple component resulting from pulse-width modulated (PWM) voltage. The frequency range of the ripples is much higher than the bandwidth of current control. Therefore the control is performed on the basis of a fundamental current component, i.e. average value with the averaging time being the PWM period. In majority of cases the average current is measured...
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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublicationIn this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...
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Determination of volatile organic compounds in water samples using membrane-solid phase microextraction (M-SPME) (headspace version)
PublicationThe results of a study on the use of membrane-solid phase microextraction (M-SPME) for sampling volatile organic compounds (VOCs) from the headspace above the liquid medium are presented. The sampled VOCs were subsequently quantified by gas chromatography (GC). Two systems were compared in this study, i.e. a novel two-phase sorption system (M-SPME), and a commercial fibre. Headspace sampling using SPME was optimized with respect...
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Principles and Developments of Solid-Phase Microextraction
PublicationSample preparation has been commonly considered a critical step of the analytical process. In this sense, remarkable efforts have been made to develop efficient sample preparation techniques which could overcome the limitations of conventional approaches. Since its inception in the early 1990’s, solid-phase microextraction (SPME) has become a widespread miniaturized sample preparation technique for extraction and preconcentration...
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Recent developments and future trends in solid phase microextraction techniques towards green analytical chemistry
PublicationSolid phase microextraction find increasing applications in the sample preparation step before chromatographic determination of analytes in samples with a complex composition. These techniques allow for integrating several operations, such as sample collection, extraction, analyte enrichment above the detection limit of a given measuring instrument and the isolation of analytes from sample matrix. In this work the information about...
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Membrane-SPME the best 'green' sample preparation technique for the gas chromatographic determination polar organic pollutants in polar media
PublicationOne of the most popular technique for sample preparation, which fulfill requirements of green analytical chemistry, is solid phase microextraction (SPME). Because of the undoubted advantages of SPME technique, solvent-free character of the extraction process and the enormous potential in analytical practice, a series of studies has been undertaken to develop new technical solutions, where improving the sensitivity and the extraction...
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Analytical procedures for determination of cocaine and its metabolites in biological samples
PublicationThe 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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Development and Validation of SPE-HPLC-MS/MS Method for Determining Cyclophosphamide in Surface Waters
PublicationA rapid and selective method for trace amounts determination of cyclophosphamide in surface water samples has been developed. A solid phase extraction SPE method for extraction and clean-up procedure has been optimized for determination by reversed-phase high-performance liquid chromatography with tandem mass spectrometry. The analyses proceed in the positive ion mode by means of the electrospray ionization method (ESI). Clean...
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New approach for e-cigarette aerosol collection by an original automatic aerosol generator utilizing melt-blown non-woven fabric
PublicationCurrently, there is lack of standardized conditions for the collection and analysis of e-cigarette (EC) aerosol. Considering the urgent need for the development of these guidelines, a procedure for EC aerosol analysis was developed. A novel automatic e-cigarette aerosol generator was designed. For the first time, melt-blown non-woven fabric was applied for the effective uptake of compounds released from vaporized e-liquid. The...
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Recent advancements in LC‐MS based analysis of biotoxins: Present and future challenges
PublicationThere has been a rising concern regarding the harmful impact of biotoxins, source of origin, and the determination of the specific type of toxin. With numerous reports on their extensive spread, biotoxins pose a critical challenge to figure out their parent groups, metabolites, and concentration. In that aspect, liquid chromatography‐mass spectrometry (LC‐MS) based analysis paves the way for its accurate identification and quantification....
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Sampling Strategies: Statistics of Sampling
PublicationEach step of the analytical procedure has a significant influence on the final result of the analysis. In the majority of cases the analytical procedure encompasses sampling because the analysis of the entire object (material) is usually not possible. Thus it is necessary to include the uncertainty related to sampling procedure in the uncertainty budget calculations. In the paper: the most important properties of the analysed...
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Organotin Compounds: Environmental Fate and Analytics
PublicationFor more than 50 years, organotin compounds have been used in almost all sectors of industry. As a consequence, specific environmental compartments are affected by the emission of these xenobiotics. The emissions of organotin compounds into the environment from paints used in the shipbuilding industry for ship hull coating, and from the plant protection products are particularly significant.In 2001, the IMO introduced a global...
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Validation of a sampling procedure
PublicationEach step of the analytical procedure influences the final results in a significant way. In the majority of cases the analytical procedure encompasses sampling because the analysis of the entire object (material) is usually not possible. Thus it is necessary to include the uncertainty related to sampling procedure in the uncertainty budget calculations. This paper describes two basic ways of estimating the sampling uncertainty,...
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THE STUDY OF WATER POLLUTION OF THE LOWER VISTULA RIVER BY PLASTIC PARTICLES
PublicationSince the beginning of widespread use of plastic its consumption and production has been constantly increasing. As a result of human activity part of waste ends up in our environment and is deposited in each of the elements of the biosphere. These impurities can be in the form of large elements, small particles fragmented to macroscopic level (pellets, facial scrub grains) and the microparticles visible under a microscope. Particularly...
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Validation of atmospheric aerosols sampling in equivalent fractions
PublicationPhysical properties and chemical composition of atmospheric aerosols are of extreme importance, in many fields of interest, namely the Environment even with legal implications. Atmospheric sampling poses inherent problems with consequent demands on sampling optimisation, with sampling strategies requiring validation. In this work a study was conducted aiming at validating the collection of atmospheric aerosols in equivalent fractions....
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Spatial and vertical distribution analysis of heavy metals in urban retention tanks sediments: a case study of Strzyza Stream
PublicationConcentrations of seven heavy metals (HMs): Zn, Cu, Pb, Cd, Ni, Cr, and Fe in core samples of bottom sediments from four retention tanks (RTs) located along the Strzyza Stream in northern Poland (Gdansk) were measured to obtain a general view of sediment quality. The recognition of contamination and potential environmental impacts is the main aim of this paper. A total of 96 sediment samples were collected from eight sampling sites...
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PBDEs in environmental samples: Sampling and analysis
PublicationThe paper reviews the subject literature concerning analytical procedures routinely sed for monitoring polybrominated diphenyl ethers (PBDE) in environmental samples. It describes and summarizes subsequent stages of analytical procedure including sample collection and preparation, extraction, clean-up and final determination. Different approaches with their advantages and limitations are presented. Special attention is drawn to...
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Using A Particular Sampling Method for Impedance Measurement
PublicationThe paper presents an impedance measurement method using a particular sampling method which is an alternative to DFT calculation. The method uses a sine excitation signal and sampling response signals proportional to current flowing through and voltage across the measured impedance. The object impedance is calculated without using Fourier transform. The method was first evaluated in MATLAB by means of simulation. The method was...
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Ultrasound assisted extraction
PublicationThe 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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Sampling Procedures in Studies of Cloud Water Composition: A Review
PublicationThe authors set out and classify the principles of operation of known types of cloud water collectors, and critically review their advantages and drawbacks. Analysis of the literature has yielded information on the parameters of various type of collectors—sampling time, the type of cloud from which the water sample was taken, droplet diameter collected with 50% efficiency (cut off), sample analytes/ parameters determined, types...
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Validation of atmospheric aerosols parallel sampling in a multifold device
PublicationIn this work, particulate matter was collected using an active sampling system consisting of a PM10 (<10 μm) inlet coupled to a multifold device containing six channels, connected to a vacuum pump. Each channel was equipped with a filter holder fitted with adequately chosen filters. The system was fixed on a metallic structure, which was placed on the roof of the laboratory building, at the Faculty of Sciences, in Lisbon. Sampling...
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Chapter 8 – Active Sampling of Air
PublicationThis chapter reviews the literature information on analytical techniques and laboratory equipment used for active sampling of air (atmospheric and indoor) in regular monitoring research. It describes popular analytical devices applied for sample collection using various types of polymeric bags, e.g. Tedlar bags, Teflon or Nafion bags, and/or stainless steel vacuum containers. It reviews literature data about the application of...
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Passive sampling
PublicationPrzedstawiono możliwości wykorzystania technik pasywnych (opartych na swobodnym ruchu cząsteczek analitu do medium zatrzymującego) w analityce środowiskowej. Omówiono przykłady wykorzystania zarówno organizmów żywych (biomonitoring) jak i urządzeń pasywnych do pobierania próbek analitów z badanego medium (powietrze, woda, gleba).
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Improved Uniform Sampling in Constrained Domains for Data-Driven Modelling of Antennas
PublicationData-driven surrogate modelling of antenna structures is an attractive way of accelerating the design process, in particular, parametric optimization. In practice, construction of surrogates is hindered by curse of dimensionality as well as wide ranges of geometry parameters that need to be covered in order to make the model useful. These difficulties can be alleviated by constrained performance-driven modelling with the surrogate...
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Phytoavailability of potentially toxic elements from industrially contaminated soils to wild grass
PublicationTopsoil and grass samples from 14 sites located in different distances from three copper mining factories and a copper smelter were collected in Srednogorie, Bulgaria. The paper discusses results of studies on the mobility of potentially toxic elements (As, Cd, Cr, Cu, Mn, Ni, Pb, Zn) from contaminated soils to wild grass Cynodon dactylon in terms of transfer (TF: soil to plant) and phytoavailability (PF: EDTA (ethylenediaminetetraacetic...
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Validation of a sampling procedure
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Extraction with environmentally friendly solvents
PublicationThe ever-increasing demand for determining compounds at low concentration levels in complex matrices requires a preliminary step of analytes isolation/enrichment in order to employ a detection technique characterized by high sensitivity at low LOQ. Sample preparation is considered as crucial part of analytical procedures. Previously the parameter of “greenness” is as important as selectivity in order to avoid using harmful organic...
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Application of passive sampling techniques as a usable tool in the field of environmental quality monitoring
PublicationAnalysis of literature data published for the past 20 years leads to the conclusion, that passive sampling technique has been developing very quickly and is commonly used in the field of monitoring pollutants in air, water and soil environment. The popularity of application of passive sampling techniques in analytical and environmental chemistry results from its many advantages e.g.: Simplicity in use, low costs of exploitation,...
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Uniform sampling in constrained domains for low-cost surrogate modeling of antenna input characteristics
PublicationIn this letter, a design of experiments technique that permits uniform sampling in constrained domains is proposed. The discussed method is applied to generate training data for construction of fast replacement models (surrogates) of antenna input characteristics. The modeling process is design-oriented with the surrogate domain spanned by a set of reference designs optimized with respect to the performance figures and/or operating...
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Comparative Study on Assisted Solvent Extraction Techniques for the Extraction of Biologically Active Compounds from Sideritis raeseri and Sideritis scardica
PublicationThe plants in the Sideritis genus are postulated to exhibit several important medicinal properties due to their unique chemical composition. To isolate the targeted phytochemical compounds, the selection of a suitable extraction method is of primary importance. In this work, a comparative study on the phytochemical profiles of various Sideritis raeseri and Sideritis scardica extracts has been carried out. An untargeted metabolomics...
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Machine Learning and Knowledge Extraction
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Facial features extraction for color, frontal images
PublicationThe problem of facial characteristic features extraction is discussed. Several methods of features extraction for color en--face photographs are discussed. The methods are based mainly on the colors features related to the specific regions of the human face. The usefulness of presented methods was tested on a database of en--face photographs consisting of 100 photographs.
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Miniaturized solid-phase extraction techniques
PublicationMore than 80% of analysis time is spent on sample collection and sample preparation, so sample preparation is a critical part of the analytical process. Traditionally, liquid-liquid extraction was developed and employed to screen for general unknowns. However, solid-phase extraction (SPE) is becoming highly popular as an alternative, due to its simplicity and economy in terms of time and solvent. This review summarizes the current...
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Ultrasound-assisted solvent extraction of porous membrane packed solid samples: A new approach for extraction of target analytes from solid samples
PublicationFor the first time, a porous membrane-based method is proposed for the extraction of target analytes directly from the solid samples. This method involves the packing of solid sample inside a porous polypropylene membrane sheet whose edges are heat-sealed to fabricate a bag. This bag is immersed in a suitable solvent and the analytes are extracted by the application of ultrasound energy. The various factors that affect the extraction...
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Atmospheric precipitation sampling for analysis
PublicationW pracy dokonano przeglądu różnych próbników stosowanych do pobierania próbek opadów atmosferycznych (wody deszczowe, mgła, wody spływne). Zaprezentowano urządzenia o różnym stopniu automatyzacji, od najprostszych konstrukcji do urządzeń kosztownych i wysoce zautomatyzowanych. W wielu publikacjach pomijane są informacje o stosowanej metodyce pobierania próbek oraz o położeniu stanowiska obserwacyjnego. Informacje te są jednak niezbędne,...
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Sampling selected solid materials
PublicationW pracy przedstawiono: ogólne zasady pobierania próbek gleby, osadów dennychi innych materiałów stałych; opis urządzeń do pobierania próbek materiałówstałych; techniki przygotowania pobranych próbek do analizy.
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Sampling water and aqueous solutions
PublicationW pracy przedstawiono: klasyfikację technik pobierania próbek ciekłych; bu-dowę szerokiej gamy urządzeń (próbników) do pobierania próbek różnego typumediów ciekłych; sposoby konserwacji próbek; terminologię związaną z tymetapem procedur analitycznych.
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Dynamic Headspace Sampling as an Initial Step for Sample Preparation in Chromatographic Analysis
PublicationThis work represents a brief summary of the use of dynamic headspace (DHS) as a technique for sample preparation in chromatographic analysis. Despite numerous developments in the area of analyte isolation and enrichment, DHS remains one of the fundamental methods used with GC. In our opinion, interest in this technique will not diminish significantly because it conforms to stipulations of green analytical chemistry. Moreover, DHS...
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A New Adaptive Method for the Extraction of Steel Design Structures from an Integrated Point Cloud
Open Research DataA new automatic and adaptive algorithm for edge extraction from a random point cloud was developed and presented herein. The proposed algorithm was tested using real measurement data. The developed algorithm is able to realistically reduce the amount of redundant data and correctly extract stable edges representing the geometric structures of a studied...
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Nanosorbents as Materials for Extraction Processes of Environmental Contaminants and Others
PublicationThe aim of this work focuses on the application of nanomaterials (NMs) in different sorp- tive extraction techniques for the analysis of organic contaminants from environmental samples of distinct matrix compositions. Without any doubt, the integration of specific NMs such as carbona- ceous nanomaterials, magnetic nanoparticles (MNPs), metal–organic frameworks (MOFs), silica na- noparticles, and ion-imprinted NPs with so lid-phase...
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Efficient uncertainty quantification using sequential sampling-based neural networks
PublicationUncertainty quantification (UQ) of an engineered system involves the identification of uncertainties, modeling of the uncertainties, and the forward propagation of the uncertainties through a system analysis model. In this work, a novel surrogate-based forward propagation algorithm for UQ is proposed. The proposed algorithm is a new and unique extension of the recent efficient global optimization using neural network (NN)-based...
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Towards Facts Extraction From Texts in Polish Language
PublicationThe Polish language differs from English in many ways. It has more complicated conjugation and declination. Because of that automatic facts extraction from texts is difficult. In this paper we present basic differences between those languages. The paper presents an algorithm for extraction of facts from articles from Polish Wikipedia. The algorithm is based on 7 proposed facts schemes that are searched for in the analyzed text....
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Gas selectivity enhancement by sampling-and-hold method in resistive gas sensors
PublicationCommercial resistive gas sensors exhibit various sensitivity to numerous gases when working at different elevated temperatures. That effect is due to a change in velocity of adsorption and desorption processes which can be modulated by temperature. Thus, to reach better selectivity of gas detection, we propose to apply a known method (called the sampling-and-hold method) of cooling down the gas sensor in the presence of the investigated...
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Application of passive sampling technique in monitoring research on quality of atmospheric air in the area of Tczew, Poland.
PublicationThis paper presents the results of atmospheric air quality research in Tczew (adjacent to the Vistula River) on the content of BTEX compounds. Analytical procedure applied during the sampling of the analytes from the air used the passive sampling technique (diffusive passive sampler, Radiello®). For determination of BTEX compounds in atmospheric air, two-stage thermal desorption technique combined with gas chromatography (TD-GC-FID)...