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In this study, we considered changes in the surface chemistry after introducing fluorine into the surface layer of nanoporous activated carbon (BAU) produced from the birch wood. Here, we examined the BAU treated with 1,1,1,2-tetrafluoroethane at the selected temperature in the range of 400–800 °C. Diverse methods, including chemical analysis, nitrogen adsorption–desorption, SEM–EDS, XPS, and 19F solid-state NMR, were used for the characterization of the prepared materials. It was found that one can introduce from 0.17 to 0.42 mmol of F per gram of BAU using fluoroalkylation at 400–500 °C. Increasing the temperature to 600 °C increases the fluorination efficiency, and the relatively high fluorine content of 1.86 mmol of F per gram of BAU can be reached. At least three group types, namely, C–F, CF2, and CF3 groups, were found by XPS and 19F solid-state NMR after such treatment. The content of “semi-ionic” fluorine drastically increases in the surface layer after high-temperature fluoroalkylation at 700 °C and 800 °C. This “semi-ionic” fluorine, in the form of C–F and CF2 groups, is directly conjugated with the π-electron system of the carbon matrix.

Here we report on the application of Mentha piperita L. extract mediated synthesis of gold nanoparticles (AuNPs) with a response in the infrared range. Chromatographic studies showed the extract of M. piperita contains secondary metabolites typically acting as reducing and stabilizing agents. To shed light on the kinetic regularities of the phytosynthesis, we examined the formation of Au nanocolloids in situ considering the impact of the content of reagents: the extract (0.25 mg/ml of dry matter) and HAuCl4 (0.025–0.975 mM) were investigated in the time range 1–75 min. The formation of non-spherical AuNPs is confirmed by TEM and UV–Vis characterization of nanocolloids. UV–Vis spectroscopy showed surface plasmon resonance peaks at 534 and > 900 nm drifting into the infrared range with time and composition of reacting mixtures. The sizes of AuNPs according to the protocol varied from 10 to near 200 nm. TEM showed pseudo-spherical, triangular, and hexagonal AuNPs. Non-ideal surface relief by AFM data for large triangular and hexagonal AuNPs and structural imperfections from HRTEM studies are demonstrated. Kinetic studies showed S-shaped kinetic curves for the reaction of HAuCl4 and the plant extract. All effective constants found for the process of NPs forming can be explained by the more intense formation of large AuNPs and by the formation of NPs of a different shape with a different absorption spectrum at the same time.

In the present work, we report, for the first time, the production of stable nanocolloids of highly monodisperse silver and gold nanoparticles (AgNPs and AuNPs) using phytosynthesis approach. With the aim to eliminate misinterpretations associated with the use of usually applied crude plant extracts, the presented study was focused on the use of polyphenolic fraction isolated from elderberry fruits (Sambucus nigra L.) for the synthesis. Obtained AgNPs and AuNP were characterized by UV–Vis and FTIR spectroscopy, DLS and TEM. We observed unexpectedly high capability of the natural polyphenols not only to form monodisperse nanoparticles but also to stabilise the concentrated nanocolloids (539 mg/L AgNPs and 739 mg/L AuNPs) for at least two years. Moreover, AgNPs showed strong antibacterial properties against pathogenic bacterial strains Staphylococcus aureus and Escherichia coli (inhibited after 15 min and totally stopped growth after 3 and 5 h at 3.125 mg/L concentration).

The accumulation of various types of waste containing both organic and inorganic metal-containing compounds is extremely hazardous for living organisms. The possibility of polymer degradation, biohydrogen synthesis, and metal detoxification via the dark fermentation of model potato waste was investigated. For this purpose, the strict anaerobic strain was isolated and identified as Clostridium butyricum. The high efficiency of dark hydrogen fermentation of potatoes with yield of hydrogen in 85.8 ± 15.3 L kg−1 VSpotato was observed. The copperand chromium salts solutions were added to the culture fluid to obtain the concentrations of 50, 100, and 200 mg L−1 Cu(II) and Cr(VI) in the active phase of growth (19 h of cultivation). Metals at a concentration of 200 mg L−1 inhibited the fermentation process the most. The hydrogen yield decreased in 7.2 and 3.6 times to 11.9 ± 2.1 and 23.8 ± 5.6 L kg−1 VSpotato in the presence of 200 mg L−1 Cu(II) and Cr(VI), respectively. The efficiencies of the chromium bioremoval in all variants of the experiment were 100%, and those of copper bioremoval were about 90%. A pure culture of strict anaerobes Clostridium butyricum strain 92 was used for the first time for the detoxification of metals. The presented results confirmed the possibility of this promising strain application for industrial H2 production and the bioremediation of contaminated sites.

We have investigated the influence of non-traditional raw materials of plant origin and natural additives on the formation of consumer properties of cupcakes with improved composition. We have defined and scientifically substantiated the formulation composition, as well as proposed model samples of cupcakes, based on the performed analysis of the organoleptic, physical-chemical indicators, food and biological value. Assessment of the organoleptic indicators was carried out based on the developed estimation scale considering such indicators as taste, smell, view at fracture, color, surface, shape, consistency following the introduction of the indicator for flavor; profilograms for samples were constructed. Based on the performed organoleptic assessment, it was established that the devised cupcakes, with the introduction of alternative raw materials to the formulation, have a good taste, flavor; they were highly appreciated by a tasting board. Due to a change to the formulation, it has become possible to reduce the caloric value of products by 16‒39 kcal/100 g. The new samples are characterized by a higher content of protein, by 18.9‒31.8 % (cupcakes without filling) and by 1.6‒1.7 times (cupcakes with filling), by a lower amount of fat, by 3.1–20.1 %, and carbohydrates ‒ by 4.7‒14.9 %. The content of essential amino acids was determined using the automated amino acid analyzer T 339. The new products demonstrated an increase in the content of amino acids, by 1.1‒1.9 times compared to control sample. The fat-acid composition of cupcakes was determined by gas chromatography applying the gas chromatographer HP 6890. The ratio of proportion of unsaturated fatty acids to saturated acids in new products increased by 1.22‒1.55 times. Mineral composition was determined by the method of atomic absorption spectrophotometry at the atomic-absorbing spectrophotometer C-115 PK. The content of mineral elements increased by 1.1‒2.7 times, of vitamins ‒ by 1.2‒2.9 times. Based on the acquired data we have justified the feasibility of extending the range of flour-based pastry products with the new types of cupcakes., Исследовано влияние нетрадиционного сырья растительного происхождения и натуральных добавок на формирование потребительских свойств кексов улучшенного состава. Определен и научно обоснованн рецептурный состав и предложены модельные образцы кексов на основе проведенного анализа органолептических, физико-химических показателей, пищевой и биологической ценности. Для оценки органолептических показателей разработана шкала оценивания, учитывая показатели: вкус, запах, вид в разломе, цвет, поверхность, форма, консистенция с введением показателя флейвор и построено профилограммы образцов. На основе проведенной органолептической оценки установлено, что разработанные кексы с внесением в рецептуру нетрадиционного сырья обладают приятными вкусом, ароматом и высоко оценены дегустационной комиссией. Благодаря изменению рецептуры удалось снизить энергетическую ценность изделий на 16–39 ккал/100 г. Новые образцы характеризуются повышенным содержанием белка на 18,9–31,8 % (кексы без начинки) и в 1,6–1,7 раз (кексы с начинкой), уменьшением количества жира на 3,1–20,1 % и углеводов - на 4,7–14,9 %. Содержание незаменимых аминокислот определяли с помощью автоматического анализатора аминокислот Т 339. В новых изделиях вырос содержание аминокислот в 1,1–1,9 раз по сравнению с контрольным образцом. Жирнокислотный состав кексов определяли методом газовой хроматографии на газовом хроматографе НР 6890. Соотношение доли ненасыщенных жирных кислот к насыщенным в новых изделиях возросло в 1,22–1,55 раз. Минеральный состав определяли методом атомно-абсорбционной спектрофотометрии на атомно-абсорбционном спектрофотометре С-115 ПК. Содержание минеральных элементов вырос в 1,1–2,7 раза, а витаминов в 1,2–2,9 раза. На основе полученных данных обоснована целесообразность расширения ассортимента мучных кондитерских изделий новыми видами кексов, Досліджено вплив нетрадиційної сировини рослинного походження та натуральних добавок на формування споживних властивостей кексів поліпшеного складу. Визначено та науково обґрунтовано рецептурний склад і запропоновано модельні зразки кексів на основі проведеного аналізу органолептичних, фізико-хімічних показників, харчової і біологічної цінності. Для оцінювання органолептичних показників розроблено шкалу оцінювання, враховуючи показники: смак, запах, вид у розломі, колір, поверхня, форма, консистенція із введенням показника флейвор та побудовано профілограми зразків. На основі проведеної органолептичної оцінки встановлено, що розроблені кекси із внесенням у рецептуру нетрадиційної сировини володіють приємними смаком, ароматом та високо оцінені дегустаційною комісією. Завдяки зміні рецептури вдалося знизити енергетичну цінність виробів на 16–39 ккал/100 г. Нові зразки характеризуються підвищеним вмістом білка на 18,9–31,8 % (кекси без начинки) та в 1,6–1,7 разів (кекси з начинкою), зменшенням кількості жиру на 3,1–20,1 % та вуглеводів – на 4,7–14,9 %. Вміст незамінних амінокислот визначали за допомогою автоматичного аналізатора амінокислот Т 339. У нових виробах зріс вміст амінокислот в 1,1–1,9 разів порівняно із контрольним зразком. Жирнокислотний склад кексів визначали методом газової хроматографії на газовому хроматографі НР 6890. Співвідношення частки ненасичених жирних кислот до насичених в нових виробах зросло в 1,22–1,55 разів. Мінеральний склад визначали методом атомно-абсорбційної спектрофотометрії на атомно-абсорбційному спектрофотометрі С-115 ПК. Вміст мінеральних елементів зріс в 1,1–2,7 раза, а вітамінів у 1,2–2,9 раза. На основі отриманих даних обґрунтована доцільність розширення асортименту борошняних кондитерських виробів новими видами кексів

The cetylpyridinium (CP) dipicrylamide (DPA) ion pair has been synthesized and characterized by the FT-IR and NMR (1H and 13C) spectroscopy, theoretically studied and tested as ion-exchanger for cetylpyridinium selective electrodes. The molecular dynamics and further DFT optimization indicate face-to-face π-π stacking interaction between pyridinium and 2,4,6-trinitrophenyl rings. The presence of weak interactions between hydrogens of cetyl chain and oxygens of nitro groups of DPA anion was confirmed by RDG function analysis. Numeric reactivity descriptors computed at the B3LYP/6-31+G(d,p) level of theory show that CP-DPA has electrophilic character and can readily react with bases. Two fabricated electrodes with the CP-DPA ion-exchanger showed near-Nernstian responses towards CP chloride in the concentration range from 1 × 10−2 to 1 × 10−5 mol/L. In the case where dibutyl phthalate was used as plasticizer, the slope equals 57.2 ± 1.3 mV/decade, whereas for the case of dioctyl phthalate the slope is 61.6 ± 1.2 mV/decade.

Here, we have examined the nanoporous activated carbon fibers (ACFs) sulfonated using the direct sulfonation and the staged method that included bromination, followed by sulfidation and oxidation. TEM confirmed the nanoporous structure of the prepared sulfonated ACFs. Nitrogen porometry and 2D nonlocal DFT simulations showed the nanoporosity reduction and variations of the pore size distribution because of the functionalization. Comparison of parameters of the SO3H groups confined in nanopores, e.g., the thermal stability and catalytic potential, showed that the most efficient acid sites, in the catalytic 2-propanol dehydration to propylene, are the SO3H groups grafted by the staged Houben–Weil methods. From the productivity of reactions used at the preparation stage, and in contrast to the one-staged aromatic substitution, the bromine addition to π sites of the edges of carbon matrix supplies enough active sites and is a reason for further high yields of the grafted thermostable SO3H groups. Hydrolysis of the grafted bromine and the surface oxidation of nanopores walls are parallel reactions that lowered the SO3H-related acidity, increasing the total acidity to 1.5 mmol g−1. The reported nanoporous sulfonated ACFs are effective to be used in the dehydration reactions catalyzed by solid acids.

C1–C5 aldehydes are toxic substances formed by chemical transformation of organic compounds into the atmosphere. Actual methods used to analyze aldehydes in environmental samples are usually slow and complex, whereas there is a need for rapid and frequent monitoring. Here, a simple, fast method for the spectrophotometric determination of the total content of aldehydes in waters has been developed. The method is based on the spectrophotometric determination at 478 nm of hydrazones in an alkaline medium, generating the hydrazon-α-oxiazinic tautomeric forms, which are formed by condensation of aldehydes and 3,5-dinitrobenzhydrazide (3,5-DHBA). We optimized the conditions of the condensation reaction, e.g., 0.05–1.0 mol L−1 H2SO4, heating at 95 °C for 10 min, and the procedure of the spectrophotometric determination of the total aldehyde content at pH higher than 11 and λmax of 478 nm. Those conditions allow the determination of the total aldehyde content in the presence of various interferences, e.g., most ketones including acetone, 2000-fold of anions: HCO3−, CH3COO−, SO42−, Cl−, F− and cations: Li+, Na+, K+, Mg2+, Ca2+, Sr2+. The calibration curve was linear in the range of 0.087–13.5 mg L−1 for aldehydes, with R2 of 0.99; the limit of detection was 27 μg L−1 (0.9 μmol L−1) and the limit of determination was 87 μg L−1 (3.2 μmol L−1) in terms of formaldehyde. The suggested procedure was successfully applied for the determination of the total aldehyde content in rainwaters and model mixtures with recovery of 97.8–102.7%. The accuracy of the procedure was confirmed by an analysis with a reference method.

The surface of microporous Norit® GAC 830 W carbon was fluoroalkylated by heating in 1,1,1,2-tetrafluoroethane and 1,1,1,2,2-pentafluoroethane at 400 and 500 °C. Elemental analysis, FTIR ATR spectroscopy, and TG studies showed the presence of ∼0.1–0.7 mmol g−1 of the fluorine-containing groups. Nitrogen adsorption measurements and quenched solid density functional theory simulations proved an increase in the mesoporosity. By combining the results of solid-state 19F NMR and XPS analyses, we determined the functionalization of the carbon surface with CF, CF3, and CF2 fluorine-containing groups. Supercapacitor electrodes prepared from these materials were subjected to the charge-discharge tests and electrical impedance measurements. During galvanostatic cycling in the aqueous 30% KOH, they showed an enhanced charge capacitance compared to the parent (830 W) and the reference (Supra 30) carbons. These observations suggest that the fluoroalkylated surface and the modified microporous structure have an additive effect on capacitance parameters of carbon electrodes studied in symmetric, negative and positive modes. The fluoroalkylation caused an increase in the surface capacitance up to 38%. Herein, we demonstrate the fluoroalkylation is a simple way to increase a capacitance of carbon electrodes.

An electrophilic bromination is used as a probe reaction to assess the reactivity of a carbon surface, as well as to prepare versatile precursors for multifunctional modifications. In this chapter, we consider the bromination of nanoporous carbon materials with liquid bromine and KBr3. This bromination was performed under different reaction protocols. Here, we report the parallel oxidation and hydrolysis during bromination and show their effect on surface chemistry. Also, the pros and cons of the usage of the proposed reaction are considered. The surface oxidation and modification rules are discussed, and the amount of introduced bromine that can be substituted by a nucleophile is presented. In general, the potential for obtaining chemically uniform surfaces covered with amino groups by amination of the surface of brominated carbon materials has been shown.

International audience; A novel sensing system was designed for pH measurements based on the enhanced and quenched photoluminescence (PL) and UV–Vis absorption of the diluted water solutions of F-, O-, and N-containing carbon nanoparticles (FON-CNPs). These FON-CNPs were solvothermally synthesized, dissolved, ultra-filtrated, and separated by thin-layer chromatography. The total fluorine content in them was found to be 1.2–1.5 mmol per gram. Their TGA showed a total weight loss of 52.7% because of the thermal decomposition and detachment of the surface groups and the partial burning of the functionalized shell on the carbon core at temperatures below 1200 °C. TEM and Raman data confirmed the presence of graphitic structures in the carbon core. From the results of ATR FTIR and UV–Vis spectroscopies, we showed that a carbon shell incorporates different functional groups covering the carbon core. The surface groups of the carbon shell include carboxyl, phenolic, and carbonyl groups. Heterocyclic N-containing and amino groups and trifluoromethyl groups supporting the hydrophobicity were also found. We suggested the possible reasons for the pH responses obtained with the sensing system considering them dependent on the de-protonation of functional groups with pH change.

The production of propylene by dehydration of 2-propanol at solid-vapor interfaces, as an example of the acidcatalyzed surface reaction, was explored by using sulfonated polyacrylonitrile-derived activated carbon fibers (PAN-ACFs). To prepare these catalysts, the PAN-ACFs obtained by onestep carbonation-activation were modified with a surface coverage of high acidity. The surface of PAN-ACFs was sulfurated with sulfur vapors at high temperatures followed by oxidation, to yield the corresponding sulfonates. The chemical analysis showed that the carbon surface layer contains from 1.28 to 6.10 mmol$\mathrm{g}^{-1}$ of sulfur, including the contribution of sulfonic $(\mathrm{S}\mathrm{O}{}_{3}\mathrm{H})$ groups. In addition to sulfonic groups, the obtained catalysts contain carboxyl, lactone, and phenolic groups, which are formed as a result of oxidation treatment. In order to understand the changes in surface chemistry and the results of sulfuration and oxidation, the sulfonated PAN-ACFs were characterized by a variety of techniques including TPD MS, TGA, SEM, and FTIR ATR. During a typical temperature mode screening at catalyst testing, it was found that the sulfonated PAN-ACFs prepared by treatment with sulfur vapor at low temperature, at $400\circ \mathrm{c}$ and $500\circ \mathrm{c}$, are very efficient at dehydrating 2-propanol. A weighed mass of 100 mg of each of these catalysts was operated at 165-175°C in 12 hours, and the catalysts were characterized by high conversion of 2-propanol and high selectivity to propylene, with a propylene yield of about 100%. Furthermore, the solid acid catalysts have high stability and strong acidity and can be reused with no significant loss in the activity after the third cycle in the subsequent 20 cycles. The preparation of solid acid catalysts from PAN-ACFs affords a novel strategy for producing propylene through alternative green and sustainable technologies.

Oxidation of activated carbon (AC) with nitric acid was carried out, and the resulting AC/HNO 3 showed high capacity when used as supercapacitor electrode material operated in the KOH electrolyte. Oxidation caused different structural changes in the AC, reducing the specific surface area and the total pore volume. After oxidation, the content of all types of oxygen-containing groups and, especially, carboxyl groups showed a significant increase. Despite the significant reduction of the specific surface area, the specific capacitance of the oxidized AC in symmetric supercapacitor electrodes is 1.4 times larger than that for the pristine AC.

The structure of a newly synthesized 3-methylthio-4-phenyl-5-phenylamino-1,2,4-triazole 1 and its hexabromotellurate salt 2 was investigated. The X-ray diffraction study of 2 gives the insight on the different interaction types in the crystal. The DFT calculations were used for the comprehensive study of the intramolecular and intermolecular forces that are present in the title 3-methylthio-4-phenyl-5-phenylamino-1,2,4-triazole hexabromotellurate. The presence of three different aromatic moieties in the investigated compounds cause π-π stacking interactions which were studied through the Hirshfeld surface analysis and with the discrimination of weak interaction types by filling color to a reduced density gradient (RDG) function isosurface. The RDG in the crystalline state was calculated upon experimental molecular geometry by partitions of the crystal to QM part that was calculated at M06-L/6-311G(d,p) level, and the semi-empirical QM part that was modeled with the PM7 method in QM/MM-like manner. The reactivity of 3-methylthio-4-phenyl-5-phenylamino-1,2,4-triazole and its protonated form was also discussed in terms of conceptual DFT theory and it shows the tendency of sulfur to be the most active center in an electrophilic and radical attack, whereas the site for nucleophilic substitution is medium dependent and not an unequivocal. NICS(1) index was used for the analysis of aromaticity of three different cyclic moieties. The present study insights the changes in the structure of a polyfunctional substituted triazole upon its protonation and explains these changes with the analysis of weak interactions.

Adsorption is currently the most promising capture technology to shorten atmospheric emissions of carbon dioxide (CO2). In this article, we report on the adsorption of CO2 onto pristine, oxidized, and aminated activated carbon (AC) sorbents. From our findings, some functionalized AC sorbents have shown very promising results in the CO2 capture process. Their maximum adsorption capacity measured by the thermogravimetric method at 20 °C varies between 2.2 and 3.9 mmol CO2/g depending on the content of diethylamino and oxygen-containing groups. The functionalization of the carbon surface with diethylamino groups improves the adsorption capacity by 30–40%. The CO2 adsorption little depends on the texture parameters of the pristine AC sorbents. In the range from 20 to 100 °C, the CO2 thermodesorption showed the effective regeneration of the sorbents. The aminated carbon surface demonstrates the best CO2 adsorption but binds the adsorbed molecules stronger than the oxidized surface, which limits the sorbent regeneration.

Here we report on the preparation of effective aminated sorbents based on activated carbon (AC), which was produced from natural raw material (Apricot pits) for the removal of heavy metal ions from wastewaters. For effective functionalization, bromination and following amination were carried out. At the amination stage, the grafted bromine groups were substituted by amino groups. Amination by ethylenediamine and monoethanolamine alcohol solutions can replace 0.52 mmol of bromine groups by 0.51–0.57 mmol of amino groups per gram of sorbent. We showed that the aminated ACs could remove 90% of Cu(II) ions from aqueous solutions containing from 4×10−5 to 1×10−3 mol/L of Cu2+. The regeneration of used sorbents and the recovery of copper were also studied to evaluate the reusability of the sorbents.

estimation of toxicity of two new classes of heterocyclic condensed cationic surfactants was performed. The general synthetic approaches for obtaining the target heterocyclic systems of 1,2,4-triazole and thieno[2,3-d]pyrimidine classes were discussed and the main routes to increasing of the chemical libraries through the efficient introduction of long-chain substituents were pointed out. The estimation of toxicity was done through: (a) the prediction of the LD 50 values of acute rat oral toxicity with using GUSAR free online service; (b) the prediction of the LC 50 values of fathead minnow with 96 hours exposure, which were predicted with using T.E.S.T. software. Computed LD 50 and LC 50 values testify that proposed heterocyclic surfactants have the toxicity rates close to the widely used surfactants like cetylpyridinium chloride, cetyltrimethylammonium bromide, and benzalkonium chloride. Consequently, target cationic surfactants of 1,2,4-triazole and thieno[2,3-d]pyrimidine series can be considered as non-toxic detergents and will be synthesized for the next biological testing as disinfectants.

Fused pyrimidines are important structural motifs in material science, medicinal chemistry, and are useful building blocks in organic synthesis. Herein we report a new approaches in preparation of condensed thieno[2,3-d]pyrimidine-containing non-toxic compounds via environmentally friendly technologies. The microbiological activity of received compounds is also discussed.

The fluoroquinolones are one of the most widely used classes of antibiotics. Enrofloxacin belongs to the class of fluoroquinolone antibiotics that have been intensively used for the treatment of bacterial infections in veterinary medicine. When antibiotic residues enter the soil, the main processes determining their persistence are sorption to organic particles and degradation. The article presents the results of studies on the sorption of enrofloxacin by different crops, provided that it’s various concentrations in the soil (1000mg·kg−1, 100mg·kg−1, 10mg·kg−1). Experimental studies have shown that the activity of absorbed antibiotics depends on its concentration in the soil and species of an agricultural plant. It was found that the most active antibiotic absorbs Lactuca sativa var. Crispa and Calendula officinalis. The lowest content of enrofloxacin among the five plants was in Mentha piperita. Adding to the soil of enrofloxacin at a concentration of 1000 mg·kg−1 leads to the formation of a high level of soil toxicity. In model ecosystems with Thymus serpillum and Mentha piperita, soil toxicity was more than 70%. The toxicity of enrofloxacin in the soil within In vivo experiments was on average 10% lower than in laboratory tests. The highest phytotoxic effect was observed in the soil of model ecosystems, where the concentration of enrofloxacin was 1000 mg·kg−1. It should be noted that in the soil where Lactuca sativa was grown, the phytotoxic effect was 56.17 % (In vitro) and 49.22% (In vivo). This is due to the active absorption of antibiotic by plants, which minimized the toxicity of the soil. The different terrestrial toxicological effects of enrofloxacin were studied using a series of bioassays and including sorption of fluoroquinolone antibiotic by five crop plants. Enrofloxacin is highly resistant, its biodegradation process is longer than other antibiotics, it is actively absorbed by the plants, and therefore it is necessary to control it content in phytoproduction.

The presented study is dedicated to the green synthesis of stable gold and silver nanoparticles using natural polyphenols isolated from blackcurrant (Ribes nigrum L.) extract. A polyphenol fraction was prepared from the raw extract of blackcurrant fruits using solid-state extraction (C 18 reversed-phase). HPLC-DAD chromatography analyses have shown that the major components of used extract were anthocyanins (delphinidin-3-glucoside, delphinidin-3-rutinoside, cyanidin-3-glucoside, and cyanidin-3-rutinoside). Green protocol for the synthesis of gold and silver nanoparticles was developed through the optimization of reaction conditions (reactants ratio, pH of solutions, reaction time and temperature). The alkali conditions were observed to be necessary for the synthesis of highly mono-disperse spherical gold nanoparticles (diameter of 10 nm).

The aim of research is studying the effect of unconventional raw materials (buckwheat, oatmeal, rye, corn, milk whey, skimmed milk powder, propolis, flower pollen, bean powder, sesame oil, pumpkin seed oil, walnut oil, walnut kernels, candied fruit mixes (apple-cherry fruits of bilberries, natural honey with floral pollen, natural honey with propolis) for the quality and safety of new muffins. The article analyzes the results of the study of the quality and safety indicators of muffins of improved composition, manufactured using non-traditional raw materials. For the preparation of new types of muffins, part of the wheat flour was replaced with buckwheat, corn, oat, milk whey, skimmed milk powder and additives of vegetable origin. Margarine has been replaced by vegetable oils. It has been established that flour confectionery products have high organoleptic properties. From the physico-chemical parameters, the mass fraction of total sugar was determined, which ranged from 28.17 % to 33.07 %, the mass fraction of fat – 16.2–20.66 %, the mass fraction of moisture – 18.0–22.0, mass fraction of ash – 0.03–1.3 %, alkalinity – 0.03–1.8°, the content of toxic elements (copper, zinc, lead, cadmium, arsenic, mercury) and microbiological indicators were also determined. Based on the data obtained as a research result, the expediency of using non-traditional raw materials to expand the range of flour confectionery products, in particular muffins is substantiated.

In this article, we report on the dehydration of bioethanol over solid acid catalysts―0.1 mmol g−1 of phosphotungstic acid loaded on activated carbon carriers obtained from waste biomass. An ethanol vapor showed a selective transformation, catalyzed by the phosphotungstic acid, into diethyl ether at between 120 and 150 °C. At the temperature range of 180–205 °C, the ethanol conversion reaches almost 99.7% with 100% selectivity towards ethylene. The adsorption and catalytic studies have shown that the oxygen-containing functional groups on carbon solids act as sites of the immobilization of phosphotungstic acid and of the ethanol adsorption contributing to alcohol dehydration.

A simple and green visual method for determination of Total Acid Number (TAN) is proposed for analysis of different engine fuels, especially biodiesel, its raw materials and blends with petroleum fuels. Two 4-hydroxystyryl N-octylpyridinium bromides dyes: 4-[-2-(4-hydroxy-3-methoxyphenyl) ethenyl]-1-octylpyridinium bromide and 4-[-2-(4-hydroxy-3,5-dymethylphenyl) ethenyl]-1-octylpyridinium bromide were used as indicators. Determination of TAN in butanol medium in the presence of 10−5–10−4 mol/L of the indicator have shown a high color contrast. Well-marked transition from pale yellow to blue/violet merocyanine form provides for determination of more than 0.01 mg/g of free fatty acids and more strong acids with RSD 1–5%. For the vast majority of samples, the value of the acid numbers found by the proposed method is in good agreement with the data obtained according to the standard ASTM D664-11 method. The optimal conditions for analysis of TAN in diesel samples were found. Particular attention is paid to the FTIR-spectrometric determination of biodiesel content in commercial diesel fuel samples. The content of biodiesel with a characteristic peak in the region that is responsible for the carbonyl group (1730–1750 cm−1) can be seen on the IR spectra.

The synthesis of a new hexabromotellurate of triazole ring-containing amino acid is described. XRD, NMR and DFT analysis of the structure of protonated [(5-amino-4-phenyl-4H-1,2,4-triazol-3-yl)sulfanyl]acetic acid testifies the protonation of the first nitrogen atom of the triazole ring. Hirshfeld surface analysis identifies numerous intermolecular interactions in the newly synthesized organic-inorganic hybrid hexabromotellurate. The DFT based comprehensive analysis of the structures of possible conformers also testifies the higher thermodynamic stability of the 1-protonated triazole cation, whereas the starting [(5-amino-4-phenyl-4H-1,2,4-triazol-3-yl)sulfanyl]acetic acid exists in solution in neutral form with the intermolecular hydrogen bond between the carboxylic acid OH group and the second nitrogen of the triazole ring. The experimentally observed NMR upfield shift of the signal of the exocyclic amino group was studied via GIAO computations and was explained through the analysis of the HOMOs of the neutral and protonated forms of the triazole compound.

A new cetylpyridinium picrate ionic liquid has been synthesized and characterized by differential thermal analysis, XRD, FT-IR, and NMR (1H and 13C) spectroscopy. Differential thermal analysis indicates the congruent melting of cetylpyridinium picrate and a temperature range of liquid state is 47–267 °C. A solid form of the sample characterized with a polymorphic transformation at 37 °C, which was confirmed via the XRD analysis. The interionic charge-transfer interactions, namely the charge transfer from the picrate anion to the cetylpyridinium cation, were detected by comparison of NMR spectra of DMSO solutions of the ionic liquid and cetylpyridinium chloride. The H–NMR chemical shifts’ differences of about 0.2 ppm and 0.1 ppm were observed in the case of the o-protons and the α-methylene group protons, respectively. Additionally, the charge-transfering between the attracted ions was confirmed by DFT calculations. Based on the solid state NMR technique, the higher ions mobility was suggested for the solid sample of the ionic liquid in comparison to the solid cetylpyridinium chloride monohydrate. Moreover, the association constants KA at 22, 30, 40, and 50 °C, obtained from the electrical conductivity measurements, clearly testifies much lower dissociation in the case of picrate. The KA values of cetylpyridinium picrate and chloride in DMSO medium at 22 °C equal 748.7 L/mol and 525.0 L/mol, respectively. The performed DFT computations of the reduced density gradient function in four proposed structures of the new ionic liquid cation-anion pair identifies the presence of weak non-covalent C H•••O N interactions between cetyl chain hydrogen atoms and nitro groups of picrate was explored through DFT calculations and analysis of the RDG function.

The present study is dedicated to development of improved method for determination of trace amounts of fluorides in natural waters which is based on the interaction of fluorides with ion associate (IA) of Al(III), salicylic aldehyde acylhydrazones (benzhydrazone (SABH) and 4-picolinhydrazone (SAPH)) and polymethine dye Astra Phloxine FF (AP). Comparison of analytical forms [Al(SABH)2]⋅AP and [Al(SAPH)2]⋅AP showed that the analytical system Al(III)-SAPH-AP is more effective, namely, a higher level of preconcentration of the analytical form is ensured by and extraction equilibrium is achieved faster. Based on the study, we propose a new, fast, simple, reliable, sensitive, and accurate method of the indirect UV–Vis-spectrophotometric determination of fluorides grounded on the interaction of fluorides with IA of Al(III), SAPH and AP with the utilization of vortex-assisted liquid-liquid microextraction (VALLME). The method is based on the discoloration of the microextract of IA of Al(III), SAPH and AP (Al-SAPH-AP) in presence of fluoride ions due to the formation of fluoride complexes of aluminum with higher stability. The effect of various factors has been studied. The optimal conditions of the UV–Vis-spectrophotometric determination of fluorides were defined as: pH 7.0–10.0, 1.0⋅10−6 mol⋅L−1 Al(III); 4.0⋅10−5 mol⋅L−1 SAPH; 1.0⋅10−6 mol⋅L−1 AP; λ = 560 nm. VALLME have been carried out in 250 μL of CCl4 at 20:1 vol ratios of aqueous and organic phases, with vortexing at 3000 rpm for 15 s followed by centrifugation at 2000 rpm for 2 min. The determination of fluorides is feasible in the presence of various interferences. The calibration curve shows the linear dependence in the range of 0.3–114 μg⋅L−1 of the fluorides concentration (R2 = 0.993) with the limit of detection of 0.086 μg⋅L−1 and the limit of determination of 0.284 μg⋅L−1. The accuracy of the proposed protocol of fluorides determination was verified towards a reference method on the samples of natural rivers waters (RSD 2.6–3.1%, recovery 98.3–101.4%).

We propose a facile route for the surface functionalization of activated carbons (ACs), which are used as a solid matrix with good mechanical properties, but have the deficiency of the active surface sites to form the AC-based solid acids (ACSA) by the direct chemical method. The route includes three stages that provide active and stable strong acidic surface layer. The surface chemistry changes at the functionalization stages were controlled with thermogravimetric (TG) and thermoprogrammed desorption (TPD) methods. N2 adsorption-desorption studies demonstrate the conservation of the AC meso- and macroporosity. According to XPS, DRIFT, TG-TPD-IR, and potential titrimetry data, the ACSA obtained by sulfonation of the styrene functionalized AC are contained up to 1.1 mmol g−1 of the strong acidic SO3H groups. The surface functionalization, as reported route, gives no prominent structural changes, from XRD data, the large macropores and transport channels maintain, from SEM data, and MicroRaman spectra show no defecting of the initial carbon matrix. The obtained ACSA are effective catalysts for the dehydration of 2-propanol and combine the high efficiency of work with the increased thermal stability of the surface layer. The thermoresistance of the ACSA significantly exceeds that of the Amberlyst-15 WET catalyst.

In this study, natural microporous activated carbon (AC) was barothermal treated with hydrogen peroxide vapors at 553 and 623 K. Nitrogen adsorption proves the formation of micro-mesoporous ACs with S ext of 350 m2 g−1 at S BET = 1250 m2 g−1. The texture of ACs drastically depends on the oxidant concentration and temperature at the treatment. Thermal behavior of the initial and obtained ACs was examined in an argon dynamic atmosphere with thermogravimetric (TG) analysis. Thermoprogrammed desorption coupled with infrared spectroscopy (TPD-IR) and MS spectroscopy monitoring of evolved gases were used to disclose the regularities of the surface groups thermodestruction. TG-TPD-IR shows that the barothermal oxidation suppresses the rich surface chemistry of the initial AC, of 1 mmol g−1 of oxygen-containing functional groups. The oxidation causes selective functionalization of the AC surface with 2.6–4.3 mmol g−1 of non-acidic quinolic (Qu) groups. The CO/CO2 release from the barothermal treated ACs has reached the Boudouard equilibrium at temperatures above 930 K. Thermal stability of two different surface centers, single spaced and vicinal Qu groups, is assigned as a factor responsible for issues related to the thermodesorption of CO/CO2 and the passage of the reversed reaction of Boudouard–Bell.

BACKGROUND Anthocyanins, compounds that represent the major group of flavonoids in berries, are one of the most powerful natural antioxidants. The aim of this study was to evaluate biological activities and comparison of anthocyanin-rich extracts prepared from chokeberry (Aronia melanocarpa), elderberry (Sambucus nigra), bilberry (Vaccinium myrtillus) and blueberry (V. corymbosum) on the porcine intestinal epithelial IPEC-1 cell line. RESULTS The IC50 values calculated in the antioxidant cell-based dichlorofluorescein assay (DCF assay) were 1.129 mg L−1 for chokeberry, 1.081 mg L−1 for elderberry, 2.561 mg L−1 for bilberry and 2.965 mg L−1 for blueberry, respectively. We found a significant negative correlation (P < 0.001) between cyanidin glycosides content and IC50 values. Moreover, extracts rich in cyanidin glycosides stimulated proliferation of IPEC-1 cells and did not have cytotoxic effect on cells at an equivalent in vivo concentration. CONCLUSIONS We found that the chokeberry and elderberry extracts rich in cyanidin glycosides possess better antioxidant and anticytotoxic activities in comparison to blueberry or bilberry extracts with complex anthocyanin profiles. © 2015 Society of Chemical Industry

One of the major goals when creating new energy systems is to provide clean and affordable energy. Currently, there is an excessive increase in the cost of fossil fuels and natural gas because of increased energy consumption and the inability to meet demand. That is why it is necessary to find reliable renewable energy sources and processes that will produce energy materials without toxic by-products in order to preserve the environment and to ensuring sustainable development and a strong economy. From environmental safety reasons, this need has led to the development of the catalytic synthesis of energetic materials from greenhouse gases; in particular, this paper proposes an efficient approach to producing methane by hydrogenation of carbon dioxide over Co–Ni catalysts.

Large transition-metal contents add desirable physical properties, such as redox reactivity, magnetism, and electric or ionic conductivity to micas and make them interesting for a variety of materials-science applications. A Mn- and F-rich tainiolite mica, ${\rm{Cs}}\left( {{\rm{Mn}}_2^{2 + }{\rm{Li}}} \right){\rm{S}}{{\rm{i}}_4}{{\rm{O}}_{10}}{{\rm{F}}_2}$ , was synthesized by a high-temperature melt-synthesis technique. Subsequent annealing for 10 days led to a single-phase and coarsegrained material. Single-crystal X-ray diffraction studies were performed and characteristic geometric parameters were compared to the analogous ferrous compound, synthetic Fe-rich tainiolite, ${\rm{Cs}}\left( {{\rm{Fe}}_2^{2 + }{\rm{Li}}} \right){\rm{S}}{{\rm{i}}_4}{{\rm{O}}_{10}}{{\rm{F}}_2}$ . Both tainiolite structures are outside the compositional stability limits for the 2:1 layer structure, and incorporating the relatively large cation Mn2+ requires significant structural adjustments in both the octahedral and tetrahedral sheets. As expected, increasing the ionic radius of the octahedral cation from 0.78 A (VIFe2+) to 0.83 A (VIMn2+) reduces the octahedral flattening angle from = 57.05° to = 56.4°, the smallest value ever observed for a tetrasilicic mica. However, even this small value is insufficient to match the lateral sizes of the tetrahedral and octahedral sheets and, in addition, unusual structural adjustments in the tetrahedral sheet are required. The average tetrahedral bond length is much greater (1.643 A) than the average value observed for tetrasilicic micas (1.607 A,) and a significant difference between the apical (1.605 A) and the basal bond lengths (1.656 A) and an enlarged basal flattening angle (τbasal = 106.29°) are noted. These parameters indicate: (1) that the 2:1 layer might be more flexible than previously thought, to allow matching of the lateral dimensions of the tetrahedral and octahedral sheets; and (2) that many other compositions that appear interesting from a materials-science point of view might be accessible.

Ferrous tainiolite, Cs[Fe2Li]o[Si4]tO10F2, has been synthesized from the melt in gastight molybdenum crucibles. The electric conductivity has been measured by impedance spectroscopy. As compared to natural micas, which are insulators, good conductivity is observed. The layered silicate can be further modified by ion exchange, which makes it a promising host structure for sensor materials. The estimated activation energy is as low as 0.79 eV. Upon Ba2+ exchange for Cs+, structural Fe2+ is partially oxidized (33%), and the layer charge is reduced significantly, resulting in a coarse-grained but swollen (monolayer hydrate) smectite-type layered silicate. Therefore, further functionalization by pillaring will be feasible resulting in a conducting microporous material. The new material has been characterized by the analysis of chemical composition (wavelength dispersive X-ray spectroscopy and laser ablation-inductively coupled plasma−mass spectrometry), differential thermal analysis, electron microscopy, Mossb...

Solid solutions in CuGaSe2–ZnSe and CuInSe2–ZnSe systems have been obtained by radio frequency heating. In order to prepare n-type phases based on CuGaSe2, p-type (CuGa)1−xZn2xSe4 and (CuIn)1−xZn2xSe4 (0.05⩽x⩽0.1) single crystals were doped by Ag, Hg, Cd, Zn implantation. The crystal structure of the solid solutions was studied by X-ray diffraction; the substitutors as well as the implantant valence states were analyzed using X-ray photoelectron spectroscopy. Hall effect, electrical conductivity, and the charge carrier mobility of an n-type zinc-implantated solid solution (CuGa)1−xZn2xSe4 and (CuIn)1−xZn2xSe4 (0.05⩽x⩽0.1) were studied.

Ferrous tainiolite, Cs[Fe2Li]o[Si4]tO10F2, has been synthesized from the melt in gastight molybdenum crucibles. The electric conductivity has been measured by impedance spectroscopy. As compared to natural micas, which are insulators, good conductivity is observed. The layered silicate can be further modified by ion exchange, which makes it a promising host structure for sensor materials. The estimated activation energy is as low as 0.79 eV. Upon Ba2+ exchange for Cs+, structural Fe2+ is partially oxidized (33%), and the layer charge is reduced significantly, resulting in a coarse-grained but swollen (monolayer hydrate) smectite-type layered silicate. Therefore, further functionalization by pillaring will be feasible resulting in a conducting microporous material. The new material has been characterized by the analysis of chemical composition (wavelength dispersive X-ray spectroscopy and laser ablation-inductively coupled plasma−mass spectrometry), differential thermal analysis, electron microscopy, Mossb...