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Документ Theoretical calculation of the activity coefficients of dilute aqueous solutions taking into account factors of electrical nature(2022) Kravchenko, M.; Bereznytska, Y.; Vasylenko, L.; Fedorenko, S.The work is devoted to development of the diluted water solutions activity coefficient calculation methodology, using the equalization of the self-agreed systems continuum electrodynamics and allocating processes which are characteristic for the electric system. The dependence of calculated ion activity factors on concentration of diluted water solutions, which are divided into three groups, was obtained. It is justified that for single- and two-valent electrolytes of the first group the influence of the general mechanism of interaction between ions is characteristic, which is determined by the action of ion electric gravity and it`s features. The growth of activity in the area of large concentration values for electrolytes containing hydrogen ion and lithium ion is shown. It has been found that the activity values in the area of electrolytes large concentrations increase is connected with the manifestation of forces of pushing electrical origin in processes, which are accompanied by redistribution of charges. On the basis of equalization for the dielectric component properties of electrolytes water solutions are described. The dependence for calculation of electric field potential, field strength and charge density were obtained. Given the change of diluted water solution internal energy for "i" class ions and free energy is obtained the expression for chemical potential ions. The calculation of the diluted water solutions activity average coefficient is proposed taking into account the nature of electric factors.Документ Вплив органо-мінеральних комплексів на міцність і власні деформації шлаколужних цементів(ОДАБА, 2019) Кривенко, П. В.; Петропавловський, О. М.; Руденко, І. І.; Константиновський, О. П.Запропоновано комплексну органо-мінеральну добавку складу «портландцементний клінкер – електроліт – поверхнево-активна речовина», використання якої в шлаколужному цементі забезпечує сповільнення строків тужавлення, підвищення показників міцності і практично відсутність усадки (0,062 мм/м). Показано особливості роботи портландцементного клінкеру у лужному середовищі, вплив добавок солей різного аніонного типу та луговміщуючих аніоноактивних ПАР на водопотребу, синтез міцності та власні деформації при гідратації та формування структури штучного каменя на його основі. Відмічена перспективність запровадження таких органо-мінеральних комплексів в якості додаткових компонентів шлаколужних цементів для регулювання їх технологічними і фізико-механічними властивостями, у т.ч. для зменшення усадки цементного каменяДокумент 35. The influence of complex additive on strength and proper deformations of alkali-activated slag cements(Trans Tech Publications Ltd, 2019) Krivenko, Pavel; Petropavlovskyi, Oleh; Rudenko, Igor; Konstantynovskyi, OleksandrThe peculiarity of alkali-activated slag cements (further, AASC’s) is increased proper deformations, which can cause increased cracking and reduced durability of structure. The paper is devoted to manage AASC’s proper deformations. The main task was to determine the composition of complex additives (further, CA’s) in system «ordinary portland cement (further, OPC) clinker -mineral compound of different anionic type - surfactant» in presence of sodium metasilicate (further, MS) to affect on hydrated AASC performance while ensuring effective structure of artificial stone by criterion of shrinkage deformations. Comparative analysis of hydrated cement systems "OPC clinker - MS", "OPC clinker - mineral compound - MS" and "OPC clinker - mineral compound - MS - surfactant" showed that the greatest effect on reduction of proper deformations occurs when the mineral compounds relate to electrolytes, i.e. Na2SO4 and NaNO3. Hydrated system is characterized by expansion (+0,062 mm/m) in presence of Na2SO4. Almost no shrinkage is supplied by application of NaNO3 (-0,062 mm/m). The obtained CA’s were tested in AASC. CA in the system “OPC clinker - NaNO3 - surfactant” provides the initial setting 43 min, the end - 65 min with accelerated strength. Investigated AASC can be classified as non-shrinking cement. This phenomena is ensured by increasing density, homogeneity and monolithicity of hydrosilicate formations, as well as due to formation of hydroaluminosilicate structures with different morphology by inclusion of nitrate anions.