Перегляд за Автор "Polumbryk, Oleg"

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Antioxidants in food systems. Mechanism of action
(2013) Polumbryk, Maksim; Ivanov, Sergey; Polumbryk, Oleg
The mechanisms of action of natural and synthetic antioxidants in food systems including lipids, proteins and carbohydrates have been discussed. It is essentially important and may predict the antioxidants effectiveness in the processes of food storage. The main benefits of industrial antioxidant utilization were considered. The most attention was given to the antioxidants mixtures and most effective synergists.
Determination of trace elements (Cr, AI, Pb) by atomic absorption in natural water of Kyiv
(2014) Polumbryk, Maksim; Ishchenko, Vera; Polumbryk, Oleg
The control of microelements in water is a one of the most important factor of the humans health in urbanized cities. ETAAS method with chemical modifiers has been used in drinking water analysis.
Developing methodology for atomic absorption determination of metallic elements in natural water
(2013) Ishchenko, Vera; Polumbryk, Oleg; Panchuk, Tamara
Inthispaper, we explore how macro component composition of natural waters impact atomization of chromium (Cr III, VI), lead (Pb) and aliminium (Al).It's been shown that the ascorbic acidis the optimal chemical modifier for electro ther mal determination of aluminiu mandlead, as wellas potassium chlorideis the one for chromium. Metrological characteristics of theme thodology have been tested on both models olutions and reals amples of natural and drinking waters.
Electronic and steric structure “Quasi-verdazyls.” I. Phosphaverdazyl and its leuco base
(1984) Nesterenko, A.; Polumbryk, Oleg; Markovskii, Leonid
By the PNDO method in an spd basis, with complete optimization of geometry, the electronic and steric structure has been calculated for different conformers of a model phosphaverdazyl and its leuco base. The results are consistent with the interpretation given previously for the ESR spectra of phosphaverdazyls. Features of electronic structure are judged in terms of their influence on the physicochemical properties and reactivity of phosphatetrazines.
Electronic structures and reactivities of derivatives of 1,4-dihydropyridines. 1. 1-methyl-3-carbamidopyridinyl radical and 1-methyl-3-carbamidopyridinium cation
(1987) Nesterenko, A.; Buryak, Nadezhda; Polumbryk, Oleg; Yasnikov, A.
The physicochemical properties and electronic and three-dimensional structures of the products of transformations of 1-methyl-1,4-dihydronicotinamide were calculated within the MINDO/3 approximation. The problems associated with their reactivities in reactions involving electron and hydrogen-atom transfer, as well as the problems of “hydride” transfer in chemical reactions, are discussed.
Polarographic investigation of donor-acceptor properties of triphenylverdazyls in propylene carbonate
(1975) Polumbryk, Oleg; Dvorko, G.; Vasil'kevich, N.; Kuznetsov, V. A.
Вивчено полярографічне окиснення і відновлення заміщених трифенілвердазильних радикалів та ДФПГ в пропіленкарбонаті при 25 °С. Отримані дані дозволяють охарактеризувати донорно-акцепторні властивості і вплив на них замісників у С-фенільному кільці вердазильних радикалів.Изучено полярографическое окисление и восстановление замещенных трифенилвердазильных радикалов и ДФПГ в пропиленкарбонате при 25 °С. Полученные данные позволили охарактеризовать донорно-акцепторные свойства и влияние на них заместителя в С-фенильном кольце вердазильных радикалов.The polarographic oxidation and reduction of the substituted triphenylverdazyl radicals and DPPH at 25 °С has been investigated. The donor-acceptor properties of those radials and influence of substituent on the C-ring were characterized on basis of these data.
Quantum-chemical investigation of spatial and electronic structure of verdazyl and its derivatives
(1979) Markovskii, Leonid; Polumbryk, Oleg; Nesterenko, A.
The unrestricted HF method in the INDO approximation with optimized geometry was used to describe the electronic structure of the hetero-ring of verdazyl and the derivatives of the latter. The results obtained are in good agreement with the experimental EPR spectra of triphenylverdazyl radical and its dipole moment. These data may be a basis for understanding and predicting the chemical properties and reactivity and its derivatives.
Synthesis of 5-nitro-N,N-diphenylhydrazinopyrimidines and investigation of their free radicals
(1980) Boldyrev, I. V.; Polumbryk, Oleg; Markovskii, Leonid; Cherkasov, V. M.
A number of 5-nitro-N,N-diphenylhydrazinopyrimidines were synthesized. Free radicals were obtaines by oxidation of these compounds with PbO2. The stabilities of 5-nitro-4-pyrimidinylhydrazyl radicals are close to the stability of the α,α-diphenyl--2,4-dinitrophenylhydrazyl radical. The structures of the compounds obtained were confirmed by the UV, IR, PMR and EPR spectra.
The use of polimers ascarriers in encapsulation of spice oleoresins
(2015) Pasichnyi, Vasyl; Khomenko, Yulia; Polumbryk, Oleg
Over the last decade, oleoresins successfully displace natural ground spices in food production due to significant advantages in application. Although most of the natural ground spices derived from tropical and subtropical materials have antioxidant properties, but they are also a source of microbial contamination, due to lesions of mold, mildew, damage by rodents and insects. To achieve sterility it is necessary to pre-heat treatment which can lead to a loss of about 20% aromatics. As is generally known, the major part of the volatile fraction is bound and released by hydrolysis, for example, heat treatment of the meat products. However, since this process is not to end, the effective concentration of the volatile substances will always be less than the extracted oleoresins and extracts. Using ground spices of poor quality make blotches on the cut of the finished product possible, and that may not comply with the organoleptic characteristics with the current regulations. За останнє десятиліття, ефірні масла успішно витісняють натуральні Спеції мелені у виробництві харчових продуктів через істотних переваг в застосуванні. Хоча більшість природних мелених спецій, отриманих з тропічних і субтропічних матеріалів володіють антиоксидантними властивостями, але вони також є джерелом мікробного забруднення, обумовленого ураженням грибків, цвілі, пошкодження гризунами та комахами. Для досягнення стерильності необхідно попередньо нагріти лікування, яке може призвести до втрати близько 20% ароматичних сполук. Як відомо, основна частина летючої фракції пов'язаний і звільнений шляхом гідролізу, наприклад, теплової обробки м'ясних продуктів. Однак, оскільки цей процес не до кінця, ефективна концентрація летких речовин завжди буде менше, ніж екстраговані ефірні масла і екстракти. Використання Спеції мелені поганої якості роблять плями на розрізі готового можливий продукт, і що вони можуть не відповідати органолептичним характеристикам з діючими правилами.
Verdazyl radicals with perfluorphenyl rings
(1978) Polumbryk, Oleg; Ryabokon, Ivan; Markovskii, Leonid
New formazans, tetrazines, and verdazyl radicals containing pentafluorphenyl residues were synthesizedon the basis of the reaction of perfluorphenylhydrazones with benzenediazonium salts. The stabilities of the free radicals obtained considerably exceed stability of the diphenylpicrylhydrazyl radical.