Yuriy V Kholin

Yuriy V Kholin
V. N. Karazin Kharkiv National University · Department of Chemical Materials Science

ScD (Physical Chemistry), Professor

About

70
Publications
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May 1992 - present
V. N. Karazin Kharkiv National University
Position
  • Professor of Materials Chemistry Department

Publications

Publications (70)
Article
Silica chemically modified with ionic liquid 1-propyl-3-methylimidazolium chloride has been examined as the material for the removal of anionic dyes Eosin Yellow (EY) and Reactive Blue 4 (RB4) from solutions. The material has the specific surface area 220 m(2)/g and average pore diameter 12.4 nm. Equilibrium and kinetics of the dye binding have bee...
Article
Full-text available
Quantitative physicochemical analysis (QPCA) enables the determination of the stoichiometric compositions and physicochemical parameters of species in equilibrium sys- tems proceeding from the composition-property dependencies. The paper discusses modifi- cations to the routine QPCA procedures required to characterize properties of reagents fixed o...
Article
The quantitative description of cooperativity effects at binding of low-molecular reagents with active reactive centers of hybrid materials requires the elaboration of convenient and reliable meaningful models and calculation procedures. The model of fixed polydentate centers was analyzed as a prospective tool for simulation of adsorption equilibri...
Article
In this work, the structural and textural properties of the SiO2/Nb2O5 system prepared by the sol-gel method and then modified by phosphoric acid were studied. The different materials were prepared, with three different mol % Nb2O5 (2.5, 5.0, and 7.5 mol %), and calcined in the temperature range of 423-1273 K. BET specific surface area determinatio...
Article
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Silica with grafted 1-n-propyl-3-methylimidazolium chloride was investigated as adsorbent for the removal of cobalt(II), copper(II), zinc(II), cadmium(II) and mercury(II) chlorides from alcoholic and aqueous solutions. The adsorption proceeds via the formation of metal-chloride anionic complexes detained near the grafted organic cations as counteri...
Article
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Different approaches to solution of linear regression problem have been implemented and tested with Python programming language. The described methods are based on two concepts: the minimization of deviation of calculated value from experimental one of the dependent variable (methods OLS, Ordinary Least Squares, and LAD, Least Absolute Deviation) a...
Article
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The results of nonempirical pKa calculations, based on different thermodynamic cycles, are presented. The inorganic systems which include up to four atoms have been investigated. The obtained data lead to conclusion about vital importance of taking into account of electron correlation effects at the B3LYP functional level. The double-zeta basis set...
Article
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Vladimir N. Tolmachov. On the 100th birth anniversary.
Conference Paper
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Surface polarity and acidity are important characteristics of silica-organic materials. Functional groups responsible for the surface acidity and affecting polarity are silanols. Another groups may affect these properties too. The report presents the results of probing surfaces of chemically modified silicas and ormosiles by fluorescent and solvato...
Article
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Artificial neural networks have proven to be a powerful tool for solving classification problems. Some difficulties still need to be overcome for their successful application to chemical data. The use of supervised neural networks implies the initial distribution of patterns between the pre-determined classes, while attribution of objects to the cl...
Article
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The property of non-ideality (cooperativity effects, energetic heterogeneity of binding centres) is often observed at probing surfaces by small ionic or molecular probes. A procedure based on the model of polydentate binding is recommended as a tool for detection and quantitative characterization of these effects. This procedure allows one to find...
Article
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An identification algorithm in qualitative chemical analysis is proposed based on the application of fuzzy (using the fuzzy set theory) similarity criteria. Examples of algorithm application to the identification of some objects are given; the stability of conclusions about the identification/nonidentification of objects to certain drawbacks is dem...
Article
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Hybrid silica-organic material with fixed n-propylamine groups was prepared by a sol–gel route and characterized by several techniques. Specific surface area of the material was 110 ± 2 m2 g−1, specific pore volume was 0.90 ± 0.01 cm3 g−1, and average pore size was 25 ± 3 nm. The specific concentration of attached amino groups was 3.28 ± 0.05 mmol...
Article
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The authors consider crisis phenomena in higher education of Ukraine of the last two decades and discuss necessary measures for improving the existing situation. It is stated that the role of chemical education in classical universities is to provide integrity, quality, and fundamental character of education. Information about Ukrainian higher educ...
Article
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The application of artificial neural networks for identifying water samples from different springs and rivers of Kharkiv based on the data about metal ions concentrations was studied. Using the river-water samples as an example, we demonstrated that the artificial neural networks enabled the correct identification of water samples, even if there we...
Article
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The Taft-Kamlet-Abboud hydrogen-bond acidity, hydrogen-bond basicity and polarity-polarizability are widely used as empirical characteristics of solvent-solute interactions. These solvatochromic parameters are determined from the absorption band positions of solvatochromic probes in the standard medium and in the medium under study. The practice of...
Article
This work describes a highly controlled post-grafting of mono and dicationic 4,4'-bipyridine alkoxysilane derivatives (Bipy(+) and Bipy(2+)) onto the surface of an ordered mesoporous silica, SBA-15. The materials obtained are designated as SBA-15/Bipy(+)Cl(-) and SBA-15/Bipy(2+)Cl(2)(-), both possessing chloride as counter ion. The regular arrangem...
Article
Full-text available
Various basis sets and methods for quantum-chemical calculations are analyzed, and the effect of the number of diffusion and polarization functions on geometry and energy characteristics of systems that simulate the surface of silica modified by aliphatic amines is studied. The contribution from correlation effects and the superposition error of th...
Article
Full-text available
On the base of probing the aminoxerogel surface by H+ ions the models have been constructed for interpretation of peculiarities of reactions occurring on the surface. The model of energetic heterogeneity postulates the presence of stoichiometrically identical sorption centers having different affinity to Н+ ions. The model of polydentate binding as...
Book
Full-text available
У навчальному посібнику представлено повні комплекти завдань (понад 400 задач) теоретичних турів ІV етапу Всеукраїнських олімпіад з хімії, що проходили у 2003–2011 роках. До всіх задач наведено розв’язки та відповіді. У книзі також наведені докладна програма підготовки учнів до ІV етапу Всеукраїнських олімпіад з хімії та список рекомендованої літер...
Book
Full-text available
У навчальному посібнику представлено повні комплекти завдань (понад 400 задач) теоретичних турів ІV етапу Всеукраїнських олімпіад з хімії, що проходили у 2003–2011 роках. До всіх задач наведено розв’язки та відповіді. У книзі також наведені докладна програма підготовки учнів до ІV етапу Всеукраїнських олімпіад з хімії та список рекомендованої літер...
Article
Full-text available
The paper focuses on the identification of geographical origin of fruits and vegetables based on their composition using statistical and chemometric methods. 58 samples of potatoes and 22 samples of apples from various districts of Kharkiv city and Kharkiv region (Ukraine) were analyzed. Concentrations of Fe, Mn, Zn, Cu, Ni, Pb, Al, Co, Cr, and Cd...
Article
This work describes the preparation and characterization of postfunctionalized ordered (SBA-15) and nonordered (SMD) mesoporous silicas with n-propyl-1,4-diazoniabicycle[2.2.2]octane chloride (DbCl) moiety. The main interest is based on the fact that these materials are excellent adsorbents due to the ability of functional groups to retain copper c...
Article
Full-text available
Представлен обзор основных хемометрических методов, используемых для решения задач класси-фикации, идентификации и обнаружения при контроле подлинности продуктов питания и пищево-го сырья. Наибольшее распространение для обработки массивов экспериментальных данных при идентификации продуктов питания получили следующие алгоритмы: метод главных компон...
Article
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К решению задач идентификации объектов по данным многооткликового эксперимента привлечен аппарат искусственных нейронных сетей: алгоритмы с обучением и самоорганизующаяся сеть Кохонена. Показана удовлетворительная надежность идентификации с помощью алгоритмов искусственных нейронных сетей при разбиении на классы наборов тестовых данных со сложной с...
Article
Full-text available
Polymers Si3Py+Cl- (A) and Si4Py+Cl- (B), 3-n-propyl (3-methylpyridinium) silsesquioxane and 3-n-propyl(4-methylpyridinium) silsesquioxane chlorides, respectively, were prepared by the sol-gel processing method. The ion exchange capacities (mmol g-1) were 0.90 and 0.81 for (A) and (B) respectively. Considering the reaction nSiPy+Cl-(s) + M2+(sln) +...
Article
An ethylenediamine-modified elastomeric network was obtained by the polycondensation reaction between poly(dimethylsiloxane), PDMS, with 2-aminoethyl-3-aminopropyltrimethoxysilane. The polymeric material was structurally characterized by its infrared spectrum and its solid state 13C and 29Si NMR. The 29Si NMR peaks at −70 and −61 ppm correspond to...
Article
Full-text available
Organofunctionalized silsesquioxane polymers obtained in a water-soluble form can be used to coat various substrates such as SiO 2 , SiO 2 /Al 2 O 3 , Al 2 O 3 , cellulose/Al 2 O 3 , and graphite or, when obtained in a water-insoluble form, can be used directly. These organo- functionalized silsesquioxanes can also be attached to poly(dimethylsilox...
Article
Full-text available
Cu(II), Zn(II), Pb(II), показана высокая энергетическая однородность материалов. Гибридные материалы с иммобилизованным ксиленоловым оранжевым могут использоваться для визуального тестового обнаружения ионов тяжелых металлов в растворах, а материалы с закрепленным кальцеином – для обнаружения Cu(II) в присутствии избытка ионов переходных металлов....
Book
Full-text available
В монографии обсуждены метрологические и вычислительные аспекты методик бинарного тестирования. Бинарное тестирование — частный случай качественного химического анализа. При бинарном тестировании заключение о присутствии или отсутствии аналита в пробе делают непосредственно по результатам применения методики (обычно с органолептической индикацией а...
Article
An n-propylpyridinium chloride-modified PDMS elastomeric network, PDMS/Py(+)Cl(-), was prepared from linear PDMS chains containing Si(CH(3))(2)OH end-groups cross-linked by 3-chloropropyltrimethoxysilane and posterior reaction with pyridine. PDMS/Py(+)Cl(-) material was structurally characterized by infrared spectroscopy (IR) and solid state (13)C...
Article
Full-text available
The interaction of Cr(III) with humus acids [fulvic (FA) and humic (HA) acids] was studied in the systems Cr(III)-FA, Cr(III)-HA, and Cr(III)-FA-HA. Chromium(III) reacts with FA extracted from the headwaters of the Moscow River and from the Krapivenka River (a tributary of Lake Seliger) to form a highly soluble high-molecular-weight Cr(III)-hydroxo...
Article
The preparation and anion exchange properties of 3-n-propyl(4-methylpyridinium) silsesquioxane chloride polymer are described. This new polymer was prepared by the sol-gel processing method and is designated as SiPic+Cl-. It is insoluble in water and showed an anion exchange capacity of 1.46x10(-3) mol g-1. The adsorption isotherms of ZnCl2, CdCl2...
Article
The state of betaine indicators, 2,6-diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate and 2,6-dichloro-4-(2,4,6-triphenylpyridinium-1-yl)phenolate, on the surfaces of aminosilicas, silica modified with aminodiphosphonic acid, and unmodified silica gel is studied with diffuse reflectance spectroscopy. The normalized polarity parameters are calcu...
Article
A study of the basic characteristics of the hybrid anilinesilica xerogel, which shows promising metal sorption properties, was carried out. A simplified approach to describe the protonization affinity of the immobilized aniline was developed, and it was compared with the known values for free aniline. The proton chemisorption process may be describ...
Article
Full-text available
The preparation, characterization as well as the adsorption properties of MCln (M= Fe(III), Co(II) and Cu(II)) from ethanol solutions by the new hybrid material cellulose acetate /Al2O3 coated with N-propyl-1,4 diazabicyclo [2.2.2] octane chloride group are described. The diamine is bonded to the cellulose acetate /Al2O3 surface by Al–O–Si covalent...
Article
Full-text available
Organomineral sorbents were prepared by sorption immobilization of Xylenol Orange on the surface of two different samples of silica gel from aqueous solutions with pH 1.68 under static conditions. The diffusion coefficients of Xylenol Organe in the near-surface layer of silica gel and the equilibrium sorption constants were determined. Wash-out of...
Article
Full-text available
The porous mixed oxide SiO2/TiO2/Sb2O5 obtained by the sol-gel processing method presented a good ion exchange property and a high exchange capacity towards the Li+, Na+ and K+ ions. In the H+/M+ ion exchange process, the H+ / Na+ could be described as presenting an ideal character. The ion exchange equilibria of Li+ and K+ were quantitatively desc...
Book
Full-text available
В сборнике nредставлены задачи с решениями по общей, неоргаиической и органической химии. По сложности они делятся на три группы: типовые: для классов с углубленным изученнем химии; конкурсные и олимпиадные. Задачи сгруппированы по относительно самостоятельным тематическим разделам. Логика построения задачника соответствует принятой в школьном курс...
Article
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A test procedure is proposed for determining total metals (Cd, Co, Cu, Fe, Hg, Ni, and Zn) using irregular 1-(2-carboxyphenyl)-5-(4-methyl-6-methoxypyrimidine-2-yl)formazan-6-cellulose as an indicator paper. Regions of unreliable color reactions were determined for each of the metals and total metals present in equal concentrations. Statistical pro...
Article
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Protolytic and associative equilibria in aqueous solutions of rhodamine B were studied. The curves of potentiometric titration with NaOH solution of the dye hydrochloride within the 5 ×10-4-3 ×10-2 M range and at an ionic strength of 0.1 M (NaCl or KCl) were treated by chemometric methods of successive modification of the equilibrium system models...
Article
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Highly dispersed zirconium phosphate was prepared by reacting celullose acetate/ZrO2 (ZrO2 = 11 wt%, 1.0 mmol g-1 of zirconium atom per gram of the material) with phosphoric acid. High power decoupling magic angle spinning (HPDEC-MAS) 31P NMR and X-ray photoelectron spectroscopy data indicated that HPO4(2-) is the species present on the membrane su...
Article
Full-text available
The numerical characterization of energetic heterogeneity of sorbents is discussed. This includes the ill-posed problem of solution of the first kind integral equations that leads to great computational difficulties. The computational methods used in this field are compared and the ways to provide reliable solutions are marked. The proposed non-ite...
Article
3-n-propylpyridiniumsilsesquioxane chloride polymer, abbreviated as SiPy+Cl-, was used to coat a porous silica gel, SiO2, surface to form the chemically modified solid SiO2/SiPy+Cl-. The resulting polymer film was well adhered to the surface and presented an ion exchange capacity of 0.74 mmol g(-1). Metal halides, MClz [M=Fe(III), Cu(II), and Zn(II...
Article
Cellulose acetate fibers with supported highly dispersed aluminum phosphate were prepared by reacting aluminum-containing cellulose acetate (Al2O3=3.5 wt.%; 1.1 mmol g−1 aluminum atom per gram of the material) with phosphoric acid. Solid-state NMR spectra (CPMAS 31P NMR) data indicated that HPO42− is the species present on the fiber surface. The sp...
Article
Full-text available
The chemisorption of hydrogen ions by silicas chemically modified with aliphatic amines was discussed. The sorption kinetics followed the model of sorption from a semi-infinite solution, with sorption being of a two-stage nature. The first stage, involving the overwhelming majority of sorption centres, was very fast. In contrast, the second stage w...
Article
Cellulose acetate fibers with supported highly dispersed aluminum phosphate were prepared by reacting aluminum-containing cellulose acetate (Al2O3=3.5wt.%; 1.1mmolg−1 aluminum atom per gram of the material) with phosphoric acid. Solid-state NMR spectra (CPMAS 31P NMR) data indicated that HPO42− is the species present on the fiber surface. The speci...
Book
Full-text available
В сборнике собраны разнообразные задачи по химии - от простых до задач международных олимпиад. Над задачником можно работать самостоятельно, этому помогут решения, комментарии и ответы ко все задачам.
Article
This work describes the preparation and characterization of a cellulose acetate fiber coated with Al(2)O(3), resulting in the organic-inorganic hybrid Cel/Al(2)O(3). Furthermore, the hybrid was modified by attaching organofunctional groups by reaction with the precursor reagents (RO)(3)Si(CH(2))(3)L (L=NH(2), NH(CH(2))(2)NH(2), NH(CH(2))(2)NH(CH(2)...
Article
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The characterization of energetic heterogeneity has been discussed in the investigation of ion-binding and chemisorption processes. Both the calculation and the interpretation of the distribution of affinity constants are ambiguous. Methodological difficulties arise connected to the fact that electrostatic effects are difficult to separate from ene...
Article
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In order to asses the contribution of sorption by complexation to the concentration of noble metals at early stages of the formation of their deposits in black shales, the sorption of Au(III), Pt(IV), Rd(II), Rh(III), Ru(IV), and Os(IV) ions was studied on ash-free preparations of humic acids (HA) separated from peat of the Tver region and marine s...
Book
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Монография посвящена развитию количественного физико-химического анализа как важнейшего метода исследования равновесий комплексообразования. Обсуждены теоретические основы, вычислительные аспекты, планирование и интерпретация результатов эксперимента. Описаны современные методы анализа данных, позволяющие повысить достоверность выводов о составе и...
Article
New chemically modified silicas – macroporous and pyrogenic – with covalently bonded chelating groups of N-benzoyl-N-phenylhydroxylamine (SiO2–BPHA) were obtained in three-step surface reaction. From elemental analysis, metal chemisorption and pH titration the concentration of bonded groups was determined as 0.076 and 0.21 mmol g−1 for Silochrome a...
Article
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Pitzer's method proposed for calculating the average activity coefficients of electrolytes in aqueous solutions was used for approximation of the dependence of the concentration and mixed equilibrium constants in solutions on the ionic strength produced by one or several supporting electrolytes. For supporting electrolytes for which experimental da...
Article
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A study is made of sorption of H+, Mn2+, Co2+, Ni2+, Cu2+, and Zn2+ ions by silica chemically modified with iminodiacetic acid. The compositions and stability constants of the products formed in reactions involving iminodiacetic acid are determined. The influence of the ionic strength of the aqueous solution on the equilibrium constants is elucidat...
Article
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To provide robust estimation of parameters in the tasks of the quantitative physicochemical analysis, the Huber’s M-estimates were adopted for the non-linear optimization. A quasi-Newton’s algorithm for the determination of stability constants and intensity factors of reagents and a corresponding software program were developed. Simulation was used...
Book
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Книга поможет каждому, кого не удовлетворяет стандартный уровень школьных знаний и кто готов углубить их, участвуя и побеждая на химических олимпиадах.
Article
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Silica chemically modified with N-benzoyl-N-phenylhydroxylamine was studied as a compound promising for sorption concentration and solid-phase spectrophotometric analysis of Fe(III). The conditions providing almost complete recovery of Fe(III) from solution with this sorbent were determined. An analytical procedure including sorption concentration...
Article
Full-text available
Frontal analysis chromatograms for CuCl2 solutions on silica gel chemically modified with amino-diphosphonic acid were recorded with a Milikhrom microcolumn liquid chromatograph. From the results of chromatographic measurements, sorption isotherms of CuCl2 were constructed. It was found that the isotherms are described by the Langmuir isotherm equa...
Article
Full-text available
Equilibrium of dissociation and homoconjugation of molecules of benzoylphenylhydroxylamine (BPHA) grafted on a silica surface was studied in the range of ionic forces of aqueous solutions 0.1-1.0 mol/1 at 20°C. Energy inhomogeneities of samples of complexing silica were examined. The experimental results were interpreted in terms of the concept of...
Article
Full-text available
Estimating of the energetic inhomogeneity of chemically modified silicas is based on solving a Fredholm integral equation of the first kind. The mathematical incorrectness of this problem, features of known methods for its solving is discussed and describe robust algorithms DAC1 and DAC2 are described. Constructing the algorithms, we have completel...
Article
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One of the most commonly used methods for investigating complex compounds forming silicas (a quantitative physico-chemical analysis, QPCA) has been considered in the paper. It was subjected to some analysis in what way the procedures of the QPCA, proposed for studying the complex formation in solutions, have to be changed to take into account the f...
Article
Determination of the number of complexes and the stoichiometric indices in their chemical formulae is the most difficult problem in simulating chemical equilibria from data on composition/property relationships. In the interactive approach presented here, test models are modified by adding new species which should quickly increase the agreement of...
Article
The model of continuous distribution of equilibrium constants is used to describe equilibria with functional groups tied to polymers. The model takes into account polymeric effects that lead to energetic differences between chemically identical groups. The calculations were carried out using the function of group distribution over equilibrium const...
Article
In the present study thermodynamic characteristics of the processes of 3-amino-5-sulfosalicylic acid complexing with rare-earth elements were determined. The pH titration method for (LnCl3 + 2H3L)(aq) (Ln = La to Lu) with the ratio n(LnCl3)/n(H3L) = 0.5 selected on the basis of the results presented in reference 1 in the temperature range 298.15 K...

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Projects (5)
Project
To study the practical applicability of the proposed material as the absorbent for the removal of d-metal compounds and as part of the electrochemical sensor for the detection of the various bio compounds.
Project
Here we studied the silica surface properties through small model systems. Started from testing our approach of pKa computations on small inorganic molecules with known dissociation constants, now we are trying to simulate the different silanol groups.