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Wyniki wyszukiwania dla: ion-selective%20electrodes
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Lead(II)-selective ionophores for ion-selective electrodes: A review
PublikacjaIn potentiometry, high selectivity of the ion-selective membranes must be assured in order to reliably measure various analytes in clinical, industrial and environmental samples. Due to the toxic nature of lead(II) it is important to monitor Pb2+ distribution in natural waters. This may be achieved by implementation of ion-selective electrodes (ISEs) with high selectivity towards lead(II) and low detection limit. A great number...
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Lead(II)-selective ionophores for ion-selective electrodes: A review
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Studies on 16-membered azothia-and azoxythiacrown ethers as ion carriers in ion selective membranes.
Publikacja16-członowe azo iazoksy korony zawierające w makropierścieniu atomy siarki były badane jako nośniki jonów w jonoselektywnych elektrodach membranowych. Związki te badane były pod kątem kompleksowania metali I i II grupy układu okresowego oraz metali ciężkich i przejściowych. Wyznaczone zostały stałe trwałości kompleksów azokoron z wybranymi kationami za pomocą metody sandwiczowej. W wyniku badań potwierdzono tworzenie się silnych...
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Equilibration Time of Solid Contact Ion-Selective Electrodes
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Ionophores in polymeric membranes for selective ion recognition:impedance studies
PublikacjaW pracy badano dwa typy elektrod: membranowe elektrody jonoselektywne (ISE) oraz elektrody nowego typu all-solid-state (AAS). Elektrody AAS zawierają przewodzącą warstwę polimerową na węglu szklistym lub platynie, na który nałożona jest membrana zawierająca jonofor. Do badań użyto dwa jonofory: p-tert-butylokaliks[4]aren-korona-4 (L1) selektywnie kompleksująca jony Na+ oraz kaliks[4]aren-korona-6 (L2) selektywnie kompleksująca...
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Kinetic Description of the Membrane–Solution Interface for Ion-Selective Electrodes
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Ionophores in polymeric membranes for selective ion recognition; impedance studies
PublikacjaBadania impedancyjne membran zawierających jonofory selektywne na kation Na+ (L1) i Cs+(L2) wykazały, ze stala dielektryczna materiału membrany zależy od typu uzytego plastyfikatora i zmienia się w zakresie od 28 do 60. Rezystancja membran zawierających ligand L1 i L2 wynosi 0.15 -1.4 Mohm w zależności od stężenia elektrolitu zewnnetrznego. Testowona dwa typy elektrod jonoselektywnych: elektrody typu ASS z polimerem przewodzącym...
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Pyrrole azocrown ethers. Synthesis, complexation, selective lead transport and ion-selective membrane electrode studies
PublikacjaOtrzymano nowe, 21-członowe, lipofilowe etery koronowe z jednostką pirolową i dwoma grupami azowymi jako składowymi makrocyklu. Właściwości kompleksujące tych nowych oraz dwóch wcześniej otrzymanych makrocykli zbadano w acetonitrylu. Ligandy te zostały użyte jako jonofory w badaniach konkurencyjnego transportu równomolowej mieszaniny jonów metali: Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Ag2+, Pb2+ w układzie woda(pH 4.9)/chloroform/woda(pH...
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A new phosphonium calix[4]arene for selective anion recognition: synthesis and studies in solution and in ion selective electrodes
PublikacjaZaprezentowana została synteza i charakteryzacja tetra (trifenylofosfoniowego) p-tert-butylkaliks[4]arenu 2. Oddziaływania z anionami były badane z użyciem (1)H oraz (31)P NMR i spektrofotometrii absorpcyjnej UV. Badania wykazały oddziaływania z anionami: CLO4-, I-, oraz SCN-. Selektywność jonoforu 2 badano również w membranowych elektrodach jonoselektywnych (ISE) PCV/o-NPOE. Elektroda zawierająca związek 2 generuje odpowiedź potencjometryczną...
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Potentiometric Solid-Contact Ion-Selective Electrode for Determination of Thiocyanate in Human Saliva
PublikacjaA new solid-contact potentiometric ion-selective electrode for the determination of SCN− (SCN-ISE) has been described. Synthesized phosphonium derivative of calix[4]arene was used as a charged ionophore. The research included selection of the ion-selective membrane composition, determination of the ISEs metrological parameters and SCN-ISE application for thiocyanate determination in human saliva. Preparation of the ISEs included...
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Synthesis and application of tetrazole di and triamide derivatives in ion-selective membrane electrodes
PublikacjaA number of tetrazole diamides and triamides have been synthesized and applied as ion carries in ion-selective membrane electrodes. Their selectivity and sensitivity were studied towards alkali, alkaline earth, transition and heavy metal cations. it was found that membranes doped with 3 and 2-nitrophenyl octyl ether exhibit an almost theoretial Nernstian response for NH+ over relatively wide concentration range. Elestrodes with...
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Poly(3-octylthiophene) as solid contact for ion-selective electrodes: contradictions and possibilities
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Ion-selective electrodes based on p-tert-butyl-homooxacalixarene di(ethyl) amides
PublikacjaPochodne dietyloamidowe p-tert-butylodihomooksakaliks[4]arenu (1), p-tert-butyloheksahomotrioksakaliks[3]arenu (2) oraz p-tert-butylokaliks[4]arenu (3) były wykorzystane jako materiał aktywny w membranach elektrod jonoselektywnych w celu sprawdzenia detekcji kationów różnych rodzajów (Na+, K+, Cs+, Mg2+, Ca2+, Mn2+, Cu2+, Zn2+, Cd2+, Pb2+ oraz kation tetrametyloammoniowy). Wyznaczono charakterystyki elektrod oraz współczynniki...
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Evaluation, Pitfalls and Recommendations for the “Water Layer Test” for Solid Contact Ion‐selective Electrodes
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Ion-selective electrodes based on p-tert-butyl-homooxacalixarene di(ethyl)amides
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Selective Synthesis of Magnetite Nanospheres with Controllable Morphologies on CNTs and Application to Lithium‐Ion Batteries
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Comparison of Fluoride Ion-Selective Electrode Based Potentiometric Methods of Fluoride Determination in Human Urine
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Solid-Contact Ion-Selective Electrodes with Highly Selective Thioamide Derivatives of p-tert-Butylcalix[4]arene for the Determination of Lead(II) in Environmental Samples
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PEDOT(PSS) as Solid Contact for Ion-Selective Electrodes: The Influence of the PEDOT(PSS) Film Thickness on the Equilibration Times
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Uncertainty of Postmortem Time Estimation Based on Potassium Ion Determination in Vitreous Humor Using Potentiometric Ion-Selective Electrode and Microwave-Induced Plasma with Optical Emission Spectrometry Methods
PublikacjaThere is a need for a reliable and independent evaluation and confirmation of the post-mortem interval (PMI) based on objective factors other than only postmortem changes or temperature measurements. Estimating the PMI by examining the concentration of potassium ions in the vitreous humor (VH) has a tradition in forensic toxicology dating back to the mid-20th century. So far, the methods for determining the presence of potassium...
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Potentiometric sensor containing set of ion selective electrodes with lipid modified membranes for quality assessment of tested non-alcoholic beverages
PublikacjaPotentiometric sensors may be a good tool for fast quality control of commercial drinks. In this work, such a sensor, containing a set of ion-selective electrodes with lipid-modified membranes (benzylhexadecyldimethylammonium chloride monohydrate, hexadecylamine, 1-dodecanol, elaidic acid, cholesterol) was used for discrimination and quality control of non-alcoholic beverages, mainly composed of sugar and citric acid. It was found...
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Dipodal Tetraamide Derivatives of 1,10-Diaza-18-Crown-6 and Alkylmalonic Acids—Synthesis and Use as Ionophores in Ion Selective Membrane Electrodes
PublikacjaNovel dipodal derivatives of an 18-membered diaza-crown ether with two diamide chains featuring methylmalonic or butylmalonic acid residues were obtained and tested as ionophores in ion-selective plasticized membrane electrodes. The objective of the study was to identify measurement conditions which ensure the most favorable performance for magnesium ion-selective electrodes. The relationship between the molar lipophilic anion...
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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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Investigation of poly(3,4-ethylenedioxythiophene) deposition method influence on properties of ion-selective electrodes based on bis(benzo-15-crown-5) derivatives
PublikacjaGlassy carbon electrodes modified by conductive polymers and membrane with derivatives of bis(benzo-15-crown-5) were tested as solid contact ion selective electrodes for K+ ions concentration determination. PEDOT with PSS, Cl- and ClO4- counter ions was electrochemically deposited onto glassy carbon substrates using four different electrochemical approaches (potentiostatic, galvanostatic, potentiodynamic and potentiostatic pulses)....
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Lower rim substituted tert-Butylcalix[4]arenes. Part 13. Interaction of calix-hydroxamates with Fe(III) and Pb(II); studies in ion-selective membrane electrodes (ISE)
PublikacjaPrzedmiotem pracy są badania oddziaływań pomiędzy trzema wybranymi hydroksamowymi pochodnymi t-butylo-kaliks[4]arenu i jonami metali z wykorzystaniem membranowych elektrod jonoselektywnych (ISE). Elektrody zawierające jako materiał aktywny wymienione związki jonoforowe charakteryzują się nernstowskim nachyleniem i szerokim zakresem liniowości na jony Pb(II), a także dobrą selektywnością na jony Pb(II)w stosunku do jonów UO2(II),...
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Lower Rim Substitutedp-tert-Butyl-Calix[4]arene. Part 15. Pb(II)-Ion-Selective Electrodes Based onp-tert-Butyl-calix[4]arene Thioamides
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Lower Rim Substituted p-tert-Butyl-Calix[4]arene. Part 15. Pb(II)-Ion-Selective Electrodes Based on p-tert-Butyl-calix[4]arene Thioamides.
PublikacjaTetra podstawione tioamidowe pochodne para-tert-butylokaliks[4]arenu (1-5) zostały zastosowane jako jonofory w membranowych elektrodach jonoselektywnych (EJS) selektywne na kationy Pb(II). Wyznaczono współczynniki selektywności. Czwartorzędowe kaliks[4]aren-tioamidy (1,2) wykazują nadzwyczaj dobrą selektywność na kationy Pb(II) w porównaniu z kaliks[4]aren-amidami. Membrany z tymi ligandami wykazują dużą trwałość, a charakterystyki...
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Solid-contact lead(II) ion-selective electrodes for potentiometric determination of lead(II) in presence of high concentrations of Na(I), Cu(II), Cd(II), Zn(II), Ca(II) and Mg(II)
PublikacjaLead and its compounds are a serious threat to the environment. Monitoring of this toxic heavy metal is a driving force for the continuous development of novel lead(II) ionophores to be applied in ion-selective electrodes. In this work a highly selective lead(II) ionophore, namely 25,26,27,28-tetrakis(piperidinylthiocarbonylmethylene)-p-tert-butylcalix[4]arene, was used in solid-contact ion-selective electrodes for determination...
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Lower Rim Substituted p-tert-Butyl Calix[4]arenes(V). Synthesis of New 5,11,17,22-tetrakis-p-tert-Butyl-25-27-bis(dialkoxyphosphorylmethoxy)calix[4] arenes and Cation Complexation Studies in Ion Selective Membrane Electrodes.
PublikacjaZaprezentowano syntezę i właściwości trzech nowych związków (2-4), bis podstawionych na dolnym obrzeżu grupami z resztą fosforylową. Związki te były badane jako jonofory w membranowych elektrodach jonoselektywnych (ISE) wykazując selektywność na kationy Rb+,K+ oraz duży i płaski kation guanidyniowyG+). Badano korelację pomiędzy stereo-strukturą związków a ich selektywnością w ISE. Stałe trwałości kompleksów z kationami metali...
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Selective detection of F- by chromogenic tetrazole receptor
PublikacjaA chromogenic anion host 4, containing two amide functionalities linked to azo dye and tetrazole rings was synthesized and its complexes with various anions were investigated. The results show that receptor 4 can recognize selectively biologically important F- ion. The binding affinity for F- was investigated by naked-eye colour change, UV-Vis and 1H NMR spectroscopy. Addition F- ion in CH3CN and DMSO to receptor 4 cause a colour...
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Chromogenic derivatives of new bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) - synthesis and properties
PublikacjaDerivatives of bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) with oxygen and sulphur atoms in the structure of aliphatic chains were successfully synthesised. The correlation between the ligand structure and its complexation properties was investigated by absorption spectroscopy. The formation of complexes of presented compounds with metal cations (Cu2+, Ni2+, Zn2+, Co2+, Fe2+ and Pb2+) was studied. Ligands 5-8 were additionally...
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Functionalized azobenzocrown ethers as sensor materials—The synthesis and ion binding properties
PublikacjaNew 13- and 16-membered azobenzocrown ethers with aromatic amino, amide, ether–ester or ether–amide residue in para position to an azo moiety were obtained. Acid–base properties and ion binding ability of the colored compounds were studied by spectroscopic methods: UV–vis, fluorimetry and 1H NMR spectroscopy. Selected azobenzocrowns were tested as ionophores in ion-selective membrane electrodes (ISEs) – classic and miniature all...
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Azomacrocyclic derivatives of imidazole: synthesis, structure, and metal ion complexation properties
PublikacjaNew azocrown ethers comprising imidazoles in the macrocycle have been synthesized. Imidazole, 2-methyl-, 4-methyl-, and 4-phenylimidazole were incorporated to form macrocyclic units by coupling with the appropriate bis-diazonium salts. The syntheseswere performed under high dilution conditions. The X-ray structure of a water adduct of the 21-membered crown ether derivative of 4-methylimidazole 8 has been solved. Metal...
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New bis(azobenzocrown)s with dodecylmethylmalonyl linkers as ionophores for sodium selective potentiometric sensors
PublikacjaNovel biscrowns 1 and 2 were synthesized from 13-membered azobenzocrown ethers containing bromoalkylenoxy chains in para position relative to the azo group. The synthesized diester molecules are dodecylmethylmalonic acid derivatives differing by the linker length. The synthesized compounds have the potential of being used as sodium ionophores in ion-selective electrodes. They were characterized and used as ionophores in classic...
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The computational methods in the development of a novel multianalyte calibration technique for potentiometric integrated sensors systems
PublikacjaIn recent years, integration and miniaturization of ion-selective electrodes (ISEs) have brought many benefits resulting in the possibility of simultaneous determination of the ions concentration in small volume samples. One of the key problems related to the preparation of potentiometric integrated sensors systems (PISSs) is a calibration procedure due to the necessity to calibrate each particular sensor separately. The main aim...
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Measurements of Subnanometer Molecular Layers
PublikacjaSelected methods of formation and detection of nanometer and subnanometer molecular layers were shown. Additionally, a new method of detection and measurement with subnanometer resolution of layers adsorbed or bonded to the gate dielectric of the ion selective field effect transistor (ISFET) was presented.
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Inhibition of impurities formation in the synthesis of N-alkyltheobromines stimulated by microwave irradiation. Cationic and anionic response of membrane electrodes
PublikacjaN-Alkyltheobromine (1-9) derivatives were obtained by reacting theobromine with appropriate alkyl halide under microwave irradiation at 100-150 W and by conventional synthesis. Formation of by-products of oxygen atom alkylation and 1-N-alkyltheobromine ring opening were considered. The presented compounds 1-5 have been studied as ion carriers in ion-selective membrane electrodes. Selectivity of these membranes was studied towards...
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Simultaneous determination of Na+, K+, Ca2+, Mg2+ and Cl- in unstimulated and stimulated human saliva using all solid state multisensor platform
PublikacjaHuman saliva is one of the body fluids which collection method is relatively simple and non-invasive. The article is dedicated to assess concentration (activity) of Na+, K+, Ca2+, Mg2+ and Cl- in fresh, unstimulated or stimulated human saliva samples using single solid contact ion-selective electrodes with conventional reference electrode and self-made multisensor platform (MP) equipped with ion-selective membranes for Na+, K+,...
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A miniaturized solid-contact potentiometric multisensor platform for determination of ionic profiles in human saliva
PublikacjaThis paper describes a miniaturized multisensor platform (MP-ISES) consisting of electrodes: a reference one (RE) and ion-selective electrodes (ISEs) for monitoring Na+, K+, Ca2+, Mg2+, Cl−, and SCN− ions and pH in human saliva. Gold electrode surface was modified by deposition of two layers: electrosynthesized PEDOT:PSS forming an intermediate layer, and ion-selective membrane. The developed ISEs were characterized by a wide linear...
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Lower rim substituted p-tert-butyl-calix[4]arene. Part 17. synthesis, extractive and ionophoric properties of p-tert-butylcalix[4]arene appended with hydroxamix acid moieties
PublikacjaThe synthesis and characterization of four p-tert-butylcalix[4]arene-hydroxamic acidc are reported. The dependence of the metal ion binding, assessed by liquid extraction of the metal nitrates from water into dichloromethane in individual and competitive experiments, on the ligand structure, is presented. The results showed that those ligands could be successfully used in separation process of trnasition and heavy metals often...
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Calix[4]arenes appended with thioamide moieties as powerful tool for heavy metals recognition
PublikacjaSelectivity of new thioamide derivatives was assessed using those ligands as sensor materials in ion-selective membrane electrodes and tested towards Pb2+ - selectivity. The influence of the nature of the thioamide function (linear, branched or cyclic substituents) on their ionophoric properties was investigated. Electrodes based on cyclic thioamide moieties are promising analytical tools for monitoring Pb2+ concentration in natural...
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Chromogenic macrocyclic derivatives of azoles - synthesis and properties,
PublikacjaNew azocrown ethers comprising imidazoles in the macrocycle have been synthesized. Imidazole, 2-methyl-, 4-methyl-, and 4-phenylimidazole were incorporated to form macrocyclic units by coupling with the appropriate bis-diazonium salts. The syntheseswere performed under high dilution conditions. The X-ray structure of a water adduct of the 21-membered crown ether derivative of 4-methylimidazole 8 has been solved. Metal...
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O-substituted tetrahydroxamate derivatives of p-tert-butylcalix[4]arene as receptors for transition and heavy metal cations
PublikacjaTetrasubstituted O-hydroxamate derivatives of p-tert-butylcalix[4]arene were applied as active materials in ion-selective membrane electrodes and were tested towards Pb-selectivity. The electrodes gave near-Nernstian characteristics for Pb2+ cations. The selectivity coefficients were determined. The influence of plasticizer on the electrode behaviour was studied. The dependence of the chemical structure on selectivity coefficients...
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Recognition and sensing of anions
PublikacjaMolecular ion recognition is one of the most intensively studied areas of supramolecular technology. The reason for this is the essential role that ions play in many biological as well as industrial processes. On the other hand, however, it has been proved that ions can have a negative impact on human health and the environment. For these reasons, it is extremly important to develop rapid and simple methods allowing the determination...
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Rotational state-changing collisions of C2H− and C2N− anions with He under interstellar and cold ion trap conditions: A computational comparison
PublikacjaWe present an extensive range of quantum calculations for the state-changing rotational dynamics involving two simple molecular anions that are expected to play some role in the evolutionary analysis of chemical networks in the interstellar environments, C2H− (X1Σ+) and C2N− (X3Σ−), but for which inelastic rates are only known for C2H−. The same systems are also of direct interest in modeling selective photo-detachment experiments...
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Calixthioamides as ionophores for transition and heavy-metal cations
PublikacjaThere is an increasing interest in applying p-tert-butylcalix[4]arenes as sensing materials in ion-selective electrodes(ISEs). Considerable efforts were made to design calixarenes that are selective for some heavy- or transitionmetal ions to be used in ISEs for controlling and monitoring the level of such pollutants in the environment. It has been reported that introduction of softer sulfur atoms instead of oxygen atoms in calix[4]arene...
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Równolegle przebiegające procesy separacji pianowej jonów Al(III), Cu(II) i Zn(II) z roztworów ich mieszanin
PublikacjaMetody flotacji jonowej i precypitacyjnej należą do procesów separacji pianowej, wykorzystujących zdolność selektywnej adsorpcji niektórych składników roztworu na powierzchni międzyfazowej gaz – ciecz. Do zalet separacji pianowej zalicza się m.in. niewysokie koszty inwestycyjne i eksploatacyjne oraz wysoką skuteczność w obróbce roztworów rozcieńczonych. Celem pracy jest ocena wpływu kluczowych parametrów na wydajność i przebieg...
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Multianalyte Calibration Methods for Potentiometric Integrated Sensors System for Determination of Ions Concentration in a Body Fluids
PublikacjaIn recent years, integration and miniaturization of ion-selective electrodes (ISEs) have brought many benefits resulting in the possibility of simultaneous determination of the ions concentration in a small sample volume. One of the key problems related to the preparation of integrated sensors systems (ISSs) is a calibration procedure due to the necessity to calibrate each particular sensor separately. The main aim of the research...
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Azo and azoxythiacrown ethers: synthesis and properties
PublikacjaA series of 16- and 18-membered azo- and azoxythiacrown ethers have been synthesized by reductive macrocyclization of the respective bis(nitrophenoxy)oxaalkanes. The aromatic residues located in the polyether region of the molecule were introduced to macrocyclic skeletons and their affinities toward different groups of metal cations in ion-selective electrodes were described. X-ray structures for one dinitropodand and one azoxybenzothiacrown...
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Wybrane aspekty oceny jakości produktów żywnościowych
PublikacjaPrzedstawiono wybrane aspekty oceny jakości produk tów żywnościo- wych: pojęcie jakości, wybrane metody oceny jakości ze szczególnym uwzględ- nieniem sztucznych potencjometrycznych sensorów sma ku składających się z szeregu elektrod typu ISE (Ion Selective Electrodes ) oraz ASSE (All Solid State Electrodes). Omówiono działanie sztucznych sensorów smaku. Przedstawiono 10 potencjometryczny sensor wprowadzony do obrotu hand lowego....