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Search results for: implicit solvent
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Analytical procedures for quality control of pharmaceuticals in terms of residual solvents content: Challenges and recent developments
PublicationResidual solvents play an important role in the synthesis of drugs and in product formulations. In addition, they pose a serious problem, that is toxicity, as many of them exhibit toxic or environmentally hazardous properties. Therefore, constant monitoring of quality control is needed. In this study, we present an overview of regulatory and general methods described by various pharmacopoeias. Then, the most commonly used methodologies...
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Environmental risk- based ranking of solvents by the combination of multimedia model and multi-criteria decision analysis
PublicationA novel procedure for assessing the environmental risk related to solvents emissions has been developed. The assessment of risk is based on hazard and exposure detailed investigations. The potential exposure related to different environmental phases is calculated with basic multimedia model, that gives the percentage distribution of solvent in environmental compartments as a result. Specific hazards– toxicological, environmental...
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Deep eutectic solvents in analytical sample preconcentration Part B: Solid-phase (micro)extraction
PublicationOne 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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Hydrophobic (deep) eutectic solvents (HDESs) as extractants for removal of pollutants from water and wastewater – A review
PublicationDeep eutectic solvents (DESs) are a new generation of solvents that attracted increasing attention in diverse applications. In last years, growing number of studies on hydrophobic (deep) eutectic solvents (HDESs) as an alternative extractants for various chemicals from aqueous environments have been reported. This article provides an overview on the usage of HDESs in liquid–liquid extraction (LLE) of different pollutants from water...
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Deep eutectic solvents with solid supports used in microextraction processes applied for endocrine-disrupting chemicals
PublicationThe 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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Computational Study of Molecular Interactions in ZnCl2(urea)2 Crystals as Precursors for Deep Eutectic Solvents
PublicationDeep eutectic solvents (DESs) are now enjoying an increased scientific interest due to their interesting properties and growing range of possible applications. Computational methods are at the forefront of deciphering their structure and dynamics. Type IV DESs, composed of metal chloride and a hydrogen bond donor, are among the less studied systems when it comes to their understanding at a molecular level. An important example...
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Hydrophobic deep eutectic solvents as “green” extraction media for polycyclic aromatic hydrocarbons in aqueous samples
PublicationThe paper presents novel nonionic and hydrophobic deep eutectic solvents which were synthesized from natural compounds, i.e., thymol, ±camphor, decanoic and 10-undecylenic acids. Fundamental physicochemical properties of the synthesized deep eutectic solvents were determined, followed by their application as extractants in ultrasound-assisted dispersive liquid-liquid microextraction to isolate and enrich polycyclic aromatic hydrocarbons...
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Superhydrophobic sponges based on green deep eutectic solvents for spill oil removal from water
PublicationThe paper described a new method for crude oil-water separation by means of superhydrophobic melamine sponges impregnated by deep eutectic solvents (MS-DES). Due to the numerous potential of two-component DES formation, simple and quick screening of 156 non-ionic deep eutectic solvents using COSMO-RS (Conductor-like Screening Model for Real Solvents) computational model was used. DES which were characterized by high solubility...
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Deep eutectic solvents based highly efficient extractive desulfurization of fuels – Eco-friendly approach
PublicationThe developed process is based on alternative, green and cheap solvents for efficient desulfurization of fuels. Several deep eutectic solvents (DESs) were successfully synthesized and studied as extraction solvents for desulfurization of model fuel containing thiophene (T), benzothiophene (BT) and dibenzothiophene (DBT). The most important extraction parameters (i.e. kind of DES, DES: fuel volume ratio, hydrogen bond acceptor:...
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Absorptive Desulfurization of Model Biogas Stream Using Choline Chloride-Based Deep Eutectic Solvents
PublicationThe paper presents a synthesis of deep eutectic solvents (DESs) based on choline chloride (ChCl) as hydrogen bond acceptor and phenol (Ph), glycol ethylene (EG), and levulinic acid (Lev) as hydrogen bond donors in 1:2 molar ratio. DESs were successfully used as absorption solvents for removal of dimethyl disulfide (DMDS) from model biogas steam. Several parameters affecting the absorption capacity and absorption rate have been...
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Silica Gel Impregnated by Deep Eutectic Solvents for Adsorptive Removal of BTEX from Gas Streams
PublicationThe paper presents the preparation of new adsorbents based on silica gel (SiO2) impregnated with deep eutectic solvents (DESs) to increase benzene, toluene, ethylbenzene, and p-xylene (BTEX) adsorption efficiency from gas streams. The DESs were synthesized by means of choline chloride, tetrapropylammonium bromide, levulinic acid, lactic acid, and phenol. The physico-chemical properties of new sorbent materials, including surface...
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Investigation of tetrabutylammonium bromide-glycerol-based deep eutectic solvents and their mixtures with water by spectroscopic techniques
PublicationDeep eutectic solvents (DES) are formed by an acceptor and a donor of hydrogen bonds. They are generally considered as a possible alternative to hazardous organic solvents in various fields. Very recently they have also appeared in analytical chemistry, used mainly for the separation of analytes before instrumental quantification. For the development of new extraction procedures, it is important, among other things, to understand...
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Closer look into the structures of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water
PublicationIn recent years, deep eutectic solvents (DES) and it’s mixture with water have become more and more attention as green solvents used in chemistry. However, there are only a few theoretical studies on the mechanisms of pure DES and DES-water complex formation. Therefore, the structural properties of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water have been investigated by means of Molecular...
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Chitin and derivative chitosan-based structures — Preparation strategies aided by deep eutectic solvents: A review
PublicationThe 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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Deep eutectic solvents microbial toxicity: Current state of art and critical evaluation of testing methods
PublicationDeep eutectic solvents (DESs) were described at the beginning of 21st century and they consist of a mixture of two or more solid components, which gives rise to a lower melting point compared to the starting materials. Over the years, DESs have proved to be a promising alternative to traditional organic solvents and ionic liquids (ILs) due to their low volatility, low inflammability, easy preparation, and usually low cost of compounds...
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Analysis of the enthalpies of transfer of Co(II) ion in mixed solvents by means of the theory of preferential solvation.
PublicationZa pomocą teorii solwatacji preferencyjnej zanalizowano entalpie przeniesienia jonu Co(II) w kilku mieszaninach wodno-organicznych i organicznych, wyznaczając parametry, które w sposób ilościowy opisują solwatację preferencyjną jonu i jego wpływ na oddziaływania między cząsteczkami rozpuszczalnika. Przeprowadzono porównanie właściwości solwatacyjnych mieszanin. Wyznaczono także średni skład sfery solwatacyjnej jonu w zależności...
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Hydrogen bonding part sigma profile of deep eutectic solvents and pure components
Open Research DataThe set includes raw data of hydrogen bonding part sigma profiles of deep eutectic solvents and pure components generated by the ADF COSMO-RS software (SCM, Netherlands).
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Modern trends in solid phase extraction: New sorbent media
PublicationBased 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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Membrane Solid Phase Microextraction - a new concept of sorbent preparation
PublicationOpracowano 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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A polynomial algorithm for solving a general max‐min fairness problem
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A Semiautomatic Experience-Based Tool for Solving Product Innovation Problem
PublicationIn this paper we present the idea of Smart Innovation Engineering (SIE) System and its implementation methodology. The SIE system is semi-automatic system that helps in carrying the process of product innovation. It collects the experiential knowledge from the formal decisional events. This experiential knowledge is collected from the group of similar products having some common functions and features. The SIE system behaves like...
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OPTIMALIZATION OF SORBENT FEEDING IN THE DRY METHOD OF FLUE GAS DESULFURIZATION
PublicationThe swiftly developing sea transport contributes to a considerable increase of fuel usage in the international shipping, which results in the escalation of toxic compounds emitted into the atmosphere. It is followed by the constantly heightened requirements limiting those emissions. In the case of sulfur oxide emission, inside of SECA (Sulfur Emission Control Area), the maximum content of sulfur in the shipping fuels used on the...
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Geometrical versus analytical approach in problem solving- an exploatory study
PublicationAbstract. In this study we analyse the geometrical visualization as a part of the process of solution. In total 263 students in the first year of study at three different universities in three different countries (Poland, Slovakia and Spain) were asked to solve four mathematical problems. The analysis of the results of all students showed that geometrical visualization for problems where there is a possibility to choose different ways...
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Deflated Preconditioned Solvers for Parametrized Local Model Order Reduction
PublicationOne of steps in the design of microwave filters is numerical tuning using full-wave simulators. Typically, it is a time-consuming process as it uses advanced computational methods, e.g. the finite-element method (FEM) and it usually requires multiple optimization steps before the specification goals are met. FEM involves solving a large sparse system of equations at many frequency points and therefore its computational cost is...
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Solving nonlinear programming problems by using O&G software.
PublicationPraca opisuje pakiet optymalizacyjny oprogramowania O&G. Umożliwia on rozwiązywanie problemów programowania nieliniowego. Użytkownik może w wygodny sposób formułować rozwiązywane zadanie i dobierać metody obliczeniowe używając interaktywnego interfejsu.
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Ultrasound-assisted deep eutectic solvent-based liquid–liquid microextraction for simultaneous determination of Ni (II) and Zn (II) in food samples
PublicationA new approach was developed for the simultaneous pre-concentration and determination of Ni (II) and Zn (II) in food samples. This method is based on ultrasound-assisted liquid–liquid micro extraction using hydrophobic deep eutectic solvent (DES) and 1,10-phenanthroline as chelating agent. The effect of several parameters, such as pH, selection and volume of DES, amount of chelating agent, time of sonication and centrifugation,...
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Optimization of vortex-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction for quantification of niclosamide in real samples
PublicationIn this manuscript, a green and fast vortex-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction (VA-HMDES-DLPME) method was developed for the selective extraction and determination of niclosamide in read samples, including rice, medicine tablets, and water samples. Here, hydrophobic magnetic deep eutectic solvents were used as the extracting solvent without requiring any centrifugation...
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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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Ni/cerium Molybdenum Oxide Hydrate Microflakes Composite Coatings Electrodeposited from Choline Chloride: Ethylene Glycol Deep Eutectic Solvent
PublicationCerium molybdenum oxide hydrate microflakes are codeposited with nickel from a deep eutectic solvent-based bath. During seven days of exposure in 0.05 M NaCl solution, the corrosion resistance of composite coating (Ni/CeMoOxide) is slightly reduced, due to the existence of some microcracks caused by large microflakes. Multielemental analysis of the solution, in which coatings are exposed and the qualitative changes in the surface...
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Structure and properties comparison of poly(ether-urethane)s based on nonpetrochemical and petrochemical polyols obtained by solvent free two-step method
PublicationThe application of thermoplastic polyurethanes (TPU) is becoming more and more extensive, and the decreasing of used petrochemical monomers and reduction of energy for the polymerization and processing processes is getting increasingly important. In this paper, we confirmed the positive influence of high bio-based monomers contents (by replacing petrochemical polyol and glycol by bio-based counterparts) on processing and properties...
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Scripta Manent. Journal of the Slovene Association of LSP Teachers
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Solubility of sulfanilamide in binary solvents containing water: Measurements and prediction using Buchowski-Ksiazczak solubility model
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Proton transfer reaction from some C–H acids to N-bases in polar aprotic solvents
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Performance evaluation of phosphonium based deep eutectic solvents coated cerium oxide nanoparticles for CO2 capture
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Theoretical and Economic Evaluation of Low-Cost Deep Eutectic Solvents for Effective Biogas Upgrading to Bio-Methane
PublicationThis paper presents the theoretical screening of 23 low-cost deep eutectic solvents (DESs) as absorbents for effective removal of the main impurities from biogas streams using a conductor-like screening model for real solvents (COSMO-RS). Based on thermodynamic parameters, i.e., the activity coefficient, excess enthalpy, and Henry’s constant, two DESs composed of choline chloride: urea in a 1:2 molar ratio (ChCl:U 1:2), and choline...
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Magnetic deep eutectic solvents as efficient media for extraction of furfural and 5-hydroxymethylfurfural from aqueous samples
PublicationThe extraction of furfural (FF) and 5-hydroxymethylfurfural (HMF) from hydrolysates is currently one of the main challenges in bio-refinery. In this work, the separation of FF and HMF from the aqueous phase was carried out using a new type of green solvents – Magnetic Deep Eutectic Solvents (MDES). A conductor-like screening model for realistic solvents (COSMO-RS) was used for the preselection of 400 MDES. MDES which exhibit the...
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Effect of choline chloride based natural deep eutectic solvents on aqueous solubility and thermodynamic properties of acetaminophen
PublicationIn this work, natural deep eutectic solvents (NADESs) containing choline chloride as hydrogen bond acceptor and 1,2-propanediol, malic acid and tartaric acid as hydrogen bond donors have been synthesized and applied to enhance the aqueous solubility of model sparingly water-soluble drug – acetaminophen. The results indicate that the greatest impact on the solubility of acetaminophen have deep eutectic solvents based on 1,2-propanediol...
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Deep eutectic solvents based assay for extraction and determination of zinc in fish and eel samples using FAAS
PublicationA 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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Deep eutectic solvents – based green absorbents for effective volatile organochlorine compounds removal from biogas
PublicationVolatile organochlorine compounds (VOXs) presented in biogas can cause many technological and environmental problems. During the combustion of biogas containing VOXs, the corrosion of installation, as well as the formation of toxic by-products (polyhalogenated dioxins and furans) and further emission to the atmosphere, may occur. Therefore, in this study, a new procedure based on physical absorption was developed. In order to meet...
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Green aspects of techniques for the determination of currently used pesticides in environmental samples
PublicationPesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical methods. The analysis of environmental samples for the presence of pesticides is very difficult: the processes involved in sample preparation are...
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Selecting the optimum location for logistics facilities using Solver
PublicationSiting logistics facilities strategically in the most costeffective geographic location is one of the key decisions a contemporary company will make. The aim of the paper is to present a solution to this problem using the Solver add-on. In the case study discussed in the paper, the company’s central warehouse location was selected based on the classic location theory, which addresses the need to minimize the cost of transport....
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Influence of Solvent Polarizability on the Keto-Enol Equilibrium in 4-[5-(naphthalen-1-ylmethyl)-1,3,4-thiadiazol-2-yl]benzene-1,3-diol
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Application of gas chromatography-mass spectrometry preceded by solvent extraction to determine volatile fatty acids in wastewater of municipal, animal farm and ladfill origin
PublicationW ramach przeprowadzonych badań została opracowana metodyka oznaczania lotnych kwasów tłuszczowych (LKT) z próbek ścieków pochodzących z oczyszczalni ścieków komunalnych, farm zwierząt oraz ze składowiska odpadów organicznych, techniką ekstrakcji ciecz-ciecz (LLE) za pomocą eteru metylo-tert-butylowego (MTBE) jako ekstahenta. Dobrano optymalne warunki chromatograficznego rozdzielania i oznaczania LKT w próbkach środowiskowych,...
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Solvent influence on the crystal structures of new cadmium tri-tert -butoxysilanethiolate complexes with 1,4-bis(3-aminopropyl)piperazine: luminescence and antifungal activity
PublicationMonocrystals of dinuclear -1,4-bis(3-aminopropyl)piperazine-4N1,N10:N4,N40-bis[bis(tri-tert-butoxysilanethiolato-S)cadmium(II)], [Cd2(C12H27O3SSi)4(C10-H24N4)] or [Cd2{SSi(OtBu)3}4(-BAPP)], 1, and polynuclear catena-poly[[bis-(tri-tert-butoxysilanethiolato-S)cadmium(II)]--1,4-bis(3-aminopropyl)piperazine-2N10:N40], [Cd(C12H27O3SSi)2(C10H24N4)]n or [Cd{SSi(OtBu)3}2(-BAPP)]n,2, with 1,4-bis(3-aminopropyl)piperazine (BAPP)...
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Solvent influence on the crystal structures of new cadmium tri-tert -butoxysilanethiolate complexes with 1,4-bis(3-aminopropyl)piperazine: luminescence and antifungal activity
PublicationMonocrystals of dinuclear 1,4-bis(3-aminopropyl)piperazine-�4N1,N10:N4,N40-bis[bis(tri-tert-butoxysilanethiolato-�S)cadmium(II)], [Cd2(C12H27O3SSi)4(C10-H24N4)] or [Cd2{SSi(OtBu)3}4(�-BAPP)], 1, and polynuclear catena-poly[[bis- (tri-tert-butoxysilanethiolato-�S)cadmium(II)]-�-1,4-bis(3-aminopropyl)piperazine-�2N10:N40], [Cd(C12H27O3SSi)2(C10H24N4)]n or [Cd{SSi(OtBu)3}2(�-BAPP)]n, 2, with 1,4-bis(3-aminopropyl)piperazine (BAPP)...
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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
PublicationThe 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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Application of analytical procedure based on accelerated solvent extraction and ion chromatography technique for determination of thiocyanate and other inorganic ions in human placenta samples
PublicationExposure of a pregnant woman during pregnancy is a special case of exposure to toxic substances. Samples of placenta collected for the studies had been prepared with the technique of accelerated solvent extraction and later analyzed for the presence of thiocyanate ion and other inorganic ions, with the use of the technique of ion chromatography. The concentration of thiocyanate ion in placenta samples collected from active smokers...
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Determination of organotin compounds in biological samples using accelerated solvent extraction, sodium tetraethylborate ethylation, and multicapillary gas chromatography flame photometric detection.
PublicationPrzedstawiono metodę oznaczania związków cynoorganicznych w próbkach biologicznych. Procedura oparta jest na wykorzystaniu ekstrakcji pod zwiększoną temperaturą i ciśnieniem (ASE) do izolacji związków cynoorganicznych z próbek wątroby morświnów odłowionych w Morzu Bałtyckim. Walidacji metody dokonano na podstawie analizy materiału odniesienia NIES No 11.
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Computational issues of solving the 1D steady gradually varied flow equation
PublicationIn this paper a problem of multiple solutions of steady gradually varied flow equation in the form of the ordinary differential energy equation is discussed from the viewpoint of its numerical solution. Using the Lipschitz theorem dealing with the uniqueness of solution of an initial value problem for the ordinary differential equation it was shown that the steady gradually varied flow equation can have more than one solution....
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Solving Multi-Ship Encounter Situations by Evolutionary Sets of Cooperating Trajectories
PublicationAutor zaproponował nowe podejście do sytuacji kolizyjnych na morzu. Polega ono na zastąpieniu ewolucyjnej trajektorii własnej ewolucyjnym zbiorem trajektorii wszystkich obiektów. Podejście to umożliwia predykcję manewrowania obiektów obcych przy jednoczesnym zachowaniu efektywności algorytmów ewolucyjnych. Dodatkowo, opracowany już wstępnie przez autorów zbiór kryteriów, ograniczeń i operatorów specjalizowanych powinien zapewnić...