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wszystkich: 868
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Wyniki wyszukiwania dla: ANALYTICAL CHEMISTRY
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Application of Bayesian Multilevel Modeling in the Quantitative Structure–Retention Relationship Studies of Heterogeneous Compounds
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Determination of pKa by pH Gradient Reversed-Phase HPLC
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Analysis of Isocratic-Chromatographic-Retention Data using Bayesian Multilevel Modeling
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How Much Can We Learn from a Single Chromatographic Experiment? A Bayesian Perspective
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Maximum A Posteriori Bayesian Estimation of Chromatographic Parameters by Limited Number of Experiments
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Simultaneous Determination of pKa and Lipophilicity by Gradient RP HPLC
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pH/Organic Solvent Double-Gradient Reversed-Phase HPLC
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Influence of pH on Retention in Linear Organic Modifier Gradient RP HPLC
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Chemically Bonded Silica Stationary Phases: Synthesis, Physicochemical Characterization, and Molecular Mechanism of Reversed-Phase HPLC Retention
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Sample Concentration of Charged Small Molecules and Peptides in Capillary Electrophoresis by Micelle to Cyclodextrin Stacking
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Statistical theory of component overlap in multicomponent chromatograms
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Porous, High Capacity Coatings for Solid Phase Microextraction by Sputtering
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Headspace Solvent Microextraction
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Extraction of mass spectra free of background and neighboring component contributions from gas chromatography/mass spectrometry data
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Miniaturization and Automation of an Internally Cooled Coated Fiber Device
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Headspace Liquid-Phase Microextraction of Chlorobenzenes in Soil with Gas Chromatography-Electron Capture Detection
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In-Tube Molecularly Imprinted Polymer Solid-Phase Microextraction for the Selective Determination of Propranolol
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Membrane Solid Phase Microextraction - a new concept of sorbent preparation
PublikacjaOpracowano nowy układ sorpcyjny do izolacji i/lub wzbogacania polarnych analitów organicznych z próbek wody z zastosowaniem techniki solid phase microextraction (SPME). Układ bazuje na oddzieleniu sorbentu polarnego od próbki za pomocą membrany hydrofobowej. Próbnik membrane-SPME (M-SPME) sporządzono z zastosowaniem polietylenoglikolu (PEG)o masie cząsteczkowej 20 kDa. Polimer ten jest rozpuszczalny w wodzie i w typowych warunkach...
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Differentiating between Inactive and Active States of Rhodopsin by Atomic Force Microscopy in Native Membranes
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Chemically modified glass fiber as a matrix-free reference material for volatile compounds
PublikacjaW pracy opisano sposób wytwarzania nowego typu bezmatrycowych materiałów odniesienia lotnych związków organicznych. Do otrzymywania lotnych analitów wykorzystano technikę termicznego rozkładu związków powierzchniowych. Jako nośnik zastosowano modyfikowane chemicznie włókna szklane. Związkiem oznaczanym był chlorek metylu.
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Studies on selectivity of hydrocarbon group type separation of petroleum vacuum distillates and base oils by HPLC.
PublikacjaW pracy przedstawiono wyniki badań nad doborem selektywnego chromatograficznego układu HPLC, umożliwiającego rozdzielenie grupowe produktów naftowych otrzymanych z destylacji próżniowej ropy naftowej, w tym, mineralnych olejów bazowych. Stwierdzono, że konieczny układ chromatograficzny wymaga wykorzystania dwóch kolumn wypełnionych żelem krzemionkowym ze związanymi grupami nitrofenopropylowymi, połączonych szeregowo z dwiema...
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Calibration of permeation passive samplers with silicone membranes based on physicochemical properties of the analytes.
PublikacjaW pracy opisano sposób kalibracji pasywnych dozymetrów permeacyjnych, wykorzystywanych w badaniach powietrza w oparciu o własności fizyko-chemiczne analitów. Stwierdzono silną zależność pomiędzy stałą kalibracyjną (K) dozymetrów i liczbą atomów węgla w cząsteczce analitu (w obrębie danej grupy związków chemicznych) dla alkoholi, alifatycznych i aromatycznych węglowodorów oraz estrów. Taka zależność występuje również pomiędzy...
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Three Wavelength Substrate System of Neutrophil Serine Proteinases
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Highly Specific Substrates of Proteinase 3 Containing 3-(2-Benzoxazol-5-yl)-l-alanine and Their Application for Detection of This Enzyme in Human Serum
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Selectivity of lithium electrodes: correlation with ion-ionophore complexstability constants and with interfacial exchange current densities
PublikacjaMembranowe elektrody selektywne na jony litu oparte na dwóch różnych dicyk-lohesyloamidowych jonoforach poddane zostały systematycznym badaniom. Potencjometrycznie wyznaczono wartości współczynników selektywności. Wartości stałych trwałości kompleksów z jonami litu, sodu i potasu wyznaczono metodą membran "sandwichowych". Transfer ładunków przez membranę oraz przez granicę faz membrana/roztwór badano metodą spektroskopii impedancyjnej....
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Silica-Based Ionogels: Nanoconfined Ionic Liquid-Rich Fibers for Headspace Solid-Phase Microextraction Coupled with Gas Chromatography–Barrier Discharge Ionization Detection
PublikacjaIn this work, hybrid silica-based materials with immobilized ionic liquids (ILs) were prepared by sol–gel technology and evaluated as solid-phase microextraction (SPME) fiber coatings. High loadings of the IL 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][TFSI]) were confined within the hybrid network. Coatings composition and morphology were evaluated using scanning electron microscopy and energy dispersive...
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Solid-Contact Ion-Selective Electrodes with Highly SelectiveThioamide Derivatives of p-tert-Butylcalix[4]arene for theDetermination of Lead(II) in Environmental Samples
PublikacjaThioamide derivatives of p-tert-butylcalix[4]arene were used as ionophores in the development of solid-contact ion-selective electrodes based on conducting polymer poly(3,4-ethylenedioxythiophene)/polystyrene sulfonate (PEDOT/PSS) which was synthesized by electrodeposition on the glassy carbon electrodes. The typical ion-selective membranes with optionally two different plasticizers [bis(2-ethylhexyl)sebacate (DOS) and 2-nitrophenyl...
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Comparability of Raman Spectroscopic Configurations: A Large Scale Cross-Laboratory Study
PublikacjaThe variable configuration of Raman spectroscopic platforms is one of the major obstacles in establishing Raman spectroscopy as a valuable physicochemical method within real-world scenarios such as clinical diagnostics. For such real world applications like diagnostic classification, the models should ideally be usable to predict data from different setups. Whether it is done by training a rugged model with data from many setups...
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Online Volatile Compound Emissions Analysis Using a Microchamber/Thermal Extractor Coupled to Proton Transfer Reaction-Mass Spectrometry
PublikacjaIndoor air is a complex and dynamic mixture comprising manifold volatile organic compounds (VOCs) that may cause physiological and/or psychological discomfort, depending on the nature of exposure. This technical note presents a novel approach to analyze VOC emissions by coupling a microchamber/thermal extractor (μ-CTE) system to a proton transfer reaction-mass spectrometer (PTR-MS). This configuration provides an alternative to...
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Application of TOPSIS for Selection and Assessment of Analytical Procedures for Ibuprofen Determination in Wastewater
PublikacjaThis paper describes the possible implementation of the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) as green analytical chemistry metrics tools. TOPSIS is one of the multi-criteria decision analysis (MCDA) tools that is applied in the selection of the best alternative from many possible. In this case we have applied it to assess the nineteen analytical procedures for ibuprofen determination in wastewater...
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Anthelmintics in the Aquatic Environment: A New Analytical Approach
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A total scoring system and software for complex modified GAPI (ComplexMoGAPI) application in the assessment of method greenness
PublikacjaEvaluating analytical methods with innovative metrics is essential to ensure the effectiveness of analytical procedures. Various approaches have been proposed to assess the performance of an analytical method and its environmental consequences, as sustainable environment and green chemistry ideology are of high importance nowadays. Considering greenness evaluation of developed analytical procedures, Green Analytical Procedure Index...
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Analytical Techniques for Determining Pharmaceutical Residues in Drinking Water – State of Art and Future Prospects
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Volatile Organohalogen Compounds Determination with Dispersive Liquid-Liquid Microextraction Applying Solvent Lighter than Water
PublikacjaBackground: Volatile organohalogen compounds (VOX) are a group of environmental pollutants that risk the quality of drinking water. These compounds are characterized by certain acute and chronic toxicities, possessing mutagenic properties. Because of these potential risks factors that these compounds cause, the maximum allowable concentrations (MACs) have been established by respective organizations. The abundance of VOX, their...
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New Trends in Sample Preparation Techniques for the Analysis of the Residues of Pharmaceuticals in Environmental Samples
PublikacjaPharmaceutical residues in the environment is a field of special interest due to the adverse effects to either human health or aquatic and soil environment. Pharmaceuticals have been already detected in underground, surface and wastewaters, soils, manure and sediments. The growing awareness of environmental pollution arising from human activity forces the need for their comprehensive determination. Environmental samples are complex...
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Current Issues in Pharmaceutical Residues in Drinking Water
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Transformations of Tetrahydrocannabinol, tetrahydrocannabinolic acid and cannabinol during their extraction from Cannabis sativa L.
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Micro-cloud point extraction for preconcentration of Aspirin in commercial tablets prior to spectrophotometric determination
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Magnetic molecularly imprinted polymer nanoparticles for selective extraction of copper from aqueous solutions prior to its flame atomic absorption determination
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Carbon Paste Electrode Modified with ZrO2 Nanoparticles and Ionic Liquid for Sensing of Dopamine in the Presence of Uric Acid
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Application of Immunological Techniques (from Vaccination to FinalMeasurements) in Determination of Pharmaceutical Residues in Environmental Samples
PublikacjaWiele biologicznie aktywnych związków wytwarzanych przez człowieka trafia ostatecznie do środowiska. Ich los środowiskowy pozostaje nadal wyzwaniem dla analityków środowiskowych i osób odpowiedzialnych za szacowanie ryzyka. Artykuł przedstawia przegląd jednej z najszerszych i bezpośrednich metod analiz środowiskowych - immunoanalitykę - ze szczególnych uwzględnieniem jej zastosowania do oznaczania jakościowego i ilościowego pozostałości...
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Permeation of mineral oils through protective glove materials in view of literature data and authors’ own studies
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Headspace Solid-Phase Microextraction Coupled with Gas Chromatography–Mass Spectrometry for the Determination of Volatile Organic Compounds in Urine
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Nanosized zinc, epigenetic changes and its relationship with DMBA induced breast cancer in rats
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Fabrication of a Molecularly Imprinted Polymer Adsorbent for Pipette Tip Micro Solid-phase Extraction of Levofloxacin from Aqueous Samples Prior to its Spectrophotometric Determination
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How to evaluate methods used in chemical laboratories in terms of the total chemical risk? – a ChlorTox Scale
PublikacjaReliable assessment of the health and environmental risk associated with the use of chemicals is critical to ob- jectively evaluate the greenness and whiteness of an analytical method. An objective and useful way of risk assessment should take into account all the relevant properties of used substances, their actual amounts needed for application of the method, and quantify the assessment result using a standardized unit. This...
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A standard analytical method as the common good and pollution abatement measure
PublikacjaA standard method can be considered as a common-good “resource,” and the solution to “the commons” problems usually lies in societal self-organization. The multi-criteria decision analysis (MCDA) was applied to model complex phenomena, such as the standard selection for imidacloprid determination. In this process, the standard was self-selected by the analytical chemistry society. The results show that analytical chemistry is a...
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Analytical eco-scale for assessing the greenness of analytical procedures
PublikacjaWe propose the analytical eco-scale as a novel comprehensive approach to evaluating the greenness of analytical methodology. It is based on assigning penalty points to parameters of an analytical process that are not in agreement with the ideal green analysis. This approach compares different parameters and different steps of the analytical process. Traditional green chemistry metrics 9e.g. Atom Economy, E-factor and Reaction Mass...
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Application of molecularly imprinted polymers in analytical chiral separations and analysis
PublikacjaOver the last two decades the process of development and application of a new types of molecular imprinted polymer (MIP) sorbents in the field of analytical chemistry have been widely described in the literature. One of the new trends in analytical chemistry practice is the use of new types of MIP sorbents as specific sorption materials constituting the stationary phase in advanced separation techniques. The following review paper...
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Overview of the three multicriteria approaches applied to a global assessment of analytical methods
PublikacjaCritical and global evaluation of analytical methods should be one of the primary goals in analytical chemistry. A holistic approach, however, requires a look at the varied features: commonly discussed validation criteria, often underrated practical and economic aspects, and typically overlooked compliance with the principles of green analytical chemistry. Carrying out such an assessment in a critical and transparent way is extremely...