Shapovalov, Sergey Sergeevich

PhD in Chemistry, Associate Professor
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Publications
62
Citations
289
h-index
9

Education

Mendeleev University of Chemical Technology of Russia
2001 — 2005, Specialist, Higher College of Chemistry of the Russian Academy of Sciences (VHK)
Skabitskii I.V., Shapovalov S.S.
The reaction of TpReOCl(StBu) (Tp = tris(pyrazolyl)borate anion) with sodium disulfide in dimethoxyethane affords the new binuclear rhenium complex [TpReO(µ-StBu)]2(µ-S2) (I). Complex I can also be synthesized by the reaction of TpReO(StBu)2 with a suspension of manganese(II) bromide in toluene accompanied by the dealkylation of one of the ligands to form one more new complex [TpReO]2(µ-S2)(µ-S) (II) containing the bridging sulfide and disulfide ligands. The structures of two crystalline solvates of complex I with dichloromethane containing the molecules with different conformations of the Re2S2 fragment (Ia and Ib) and complex II are studied by X-ray diffraction (XRD) (CIF files ССDC nos. 2262677, 2262678, and 2267423 for Ia, Ib, and II, respectively).
Popova A.S., Ogarkova N.K., Shapovalov S.S., Skabitsky I.V., Kultyshkina E.K., A.Yakushev I., Vargaftik M.N.
2022-09-01 citations by CoLab: 5 Abstract
Novel highly soluble palladium-based complexes with ferrocenecarboxylic acid of general formula [Pd(lut) 2 (FcCOO) 2 ] (lut is 2,6-or 3,4-lutidines) were synthesized and structurally characterized by single-crystal X-ray diffraction. The catalytic oxidation of 1,2-diphenyl-acetylene with these complexes gave dibenzo[ a , e ]pentalene derivative along with other products.
Ioni Y.V., Ivannikova A.S., Shapovalov S.S., Gubin S.P.
2022-04-25 citations by CoLab: 5 Abstract
The interaction of graphene oxide as a finely dispersed powder and a 100 µm film with chlorine at room temperature was studied. The graphene oxide samples formed upon treatment with Cl2 were characterized by various physicochemical techniques. Sorption of chlorine atoms on the surface of graphene oxide layers was detected. The adsorbed chlorine atoms can be removed from the graphene oxide structure only by heating in vacuum.
Torubaev Y., Skabitskiy I., Shapovalov S., Tikhonova O., Popova A.
Crystals Q2 Q3 Open Access
2022-03-17 citations by CoLab: 1 PDF Abstract
This work is focused on the complex interplay of geometry of I⋯X halogen bonds (HaB) and intermolecular interaction energy in two isomorphic cocrystals [CpFe(CO)2X] (C2I4) (X = Cl (1), Br (2)). Their IR-spectroscopic measurements in solid state and solution demonstrate the blue-shift of CO vibration bands, resulting from I⋯X HaB. The reluctance of their iodide congener [CpFe(CO)2I] to form the expected cocrystal [CpFe(CO)2I] (C2I4) is discussed in terms of different molecular electrostatic potential (MEP) of the surface of iodide ligands, as compared with chloride and bromide, which dictate a different angular geometry of HaB around the metal-I and metal-Br/Cl HaB acceptors. This study also suggests C2I4 as a reliable HaB donor coformer for metal-halide HaB acceptors in the crystal engineering of hybrid metal–organic systems.
Skabitskii I.V., Shapovalov S.S.
Abstract The reaction of TpReOCl 2 (Tp is the tris(pyrazolyl)borate anion) with methanol in the presence of triethylamine affords new rhenium alkoxide complex TpReO(OMe) 2 ( I ). Unlike the starting complex resistant to hydrolysis, complex I reacts with water in toluene to form the dimeric complex [TpReO(μ-O)] 2 ( II ). The action of a large amount of water in acetone also leads to the decomposition of some Tp ligands and formation of the cationic complex [(TpReO) 2 (μ-O)(μ-C 3 H 3 N 2 )]ReO 4 ( III ) with the pyrazolate bridging ligand and perrhenate anion on the external sphere. The treatment of complex I with acetic anhydride gives the rhenium tris(pyrazolyl)borate complex bearing terminal acetate substituents TpReO(OAc) 2 ( IV ). The synthesized complexes are characterized by IR and NMR spectroscopy, and their structures are determined by X-ray diffraction (CIF files CCDC nos. 2081834 ( I ), 2081835 ( II ), 2081836 ( III ), 2081837 ( IV )).
Shapovalov S.S., Mayorova N.A., Modestov A.D., Shiryaev A.A., Egorov A.V., Grinberg V.A.
Catalysts Q2 Q2 Open Access
2022-02-24 citations by CoLab: 9 PDF Abstract
Nanosized bimetallic PtMo, PtFe and trimetallic PtMoSn catalysts deposited on highly dispersed carbon black Vulcan XC-72 were synthesized from the cluster complex compounds PtCl(P(C6H5)3)(C3H2N2(CH3)2)Mo(C5H4CH3)(CO)3, Pt(P(C6H5)3)(C3N2H2(CH3)2)Fe(CO)3(COC6H5C2C6H5), and PtCl(P(C6H5)3)(C3N2H2(CH3)2)C5H4CH3Mo(CO)3SnCl2, respectively. Structural characteristics of these catalysts were studied using X-ray diffraction (XRD), microprobe energy dispersive spectroscopy (EDX), and transmission electron microscopy (TEM). The synthesized catalysts were tested in aqueous 0.5 M H2SO4 in a three-electrode electrochemical cells and in single fuel cells. Electrocatalytic activity of PtMo/C and PtFe/C in the oxygen reduction reaction (ORR) and the activity of PtMoSn/C in electrochemical oxidation of ethanol were evaluated. It was shown that specific characteristics of the synthesized catalysts are 1.5–2 times higher than those of a commercial Pt(20%)/C catalyst. The results of experiments indicate that PtFe/C, PtMo/C, and PtMoSn/C catalysts prepared from the corresponding complex precursors can be regarded as promising candidates for application in fuel cells due to their high specific activity.
Kozetozhets I.V., Panasyuk G.P., Semenov E.A., Buzanov G.A., Avdeeva V.V., Danchevskaya M.N., Tsvetov N.S., Shapovalov S.S., Vasil’ev M.G.
2021-12-01 citations by CoLab: 2 Abstract
Highly dispersed CaO has been synthesized by heating an aqueous solution of calcium nitrate and D-glucose up to 800°C. Calcium oxide is formed with an average particle size of 0.4 μm. According to X-ray powder diffraction and DSC studies, after exposure to the air for 24 h at 25°C the sample consists of crystalline phases of hydroxide (17.7 wt %), carbonate (20.0 %), calcium oxide (up to 5.5 wt %), and up to 56.8 wt % of the sample consist of a non-crystalline X-ray amorphous CaO phase. The synthesized highly dispersed CaO has been stored in the air at 25°C for 7 days. According to X-ray powder diffraction and DSC methods, the obtained sample consists of crystalline phases of calcium hydroxide (12.8 wt %) and calcium carbonate (83.4 wt %). The calculations error does not exceed 10%.
Shapovalov S.S., Popova A.S., Ioni Y.V.
2021-11-18 citations by CoLab: 4 Abstract
Efficient methods have been developed for the oxidation of diphenylacetylene to 1,2-diphenyldiketone (benzyl) in DMSO both on commercially available heterogeneous carbon-containing palladium catalysts and on composite materials Pd-graphene and Pd-graphene oxide.
Shapovalov S., Tikhonova O., Skabitsky I.
2021-09-14 citations by CoLab: 0 PDF Abstract
The investigation of the coordination chemistry of heterometallic transition-metal complexes of palladium (Pd) and rhenium (Re) led to the isolation and crystallographic characterization of tetrakis(1,3-dimethylimidazolium-2-ylidene)palladium(II) hexadecacarbonyltetrarhenium diethyl ether disolvate, [Pd(C5H8N2)4][Re4(CO)16]·2C4H10O or [Pd(IMe)4][Re4(CO)16]·2C4H10O, (1), and octa-μ-carbonyl-dicarbonyltetrakis(triphenylphosphane)palladiumdirhenium, [Pd4Re2(C18H15P)4(CO)10] or Pd4Re2(PPh3)4(μ-CO)8(CO)2, (2), from the reaction of Pd(PPh3)4 with 1,3-dimethylimidazolium-2-carboxylate and Re2(CO)10 in a toluene–acetonitrile mixture. In complex 1 the Re—Re bond lengths [2.9767 (3)–3.0133 (2) Å] are close to double the covalent Re radii (1.51 Å). The palladium–rhenium carbonyl cluster 2 has not been structurally characterized previously; the Pd—Re bond lengths [2.7582 (2)–2.7796 (2) Å] are about 0.1 Å shorter than the sum of the covalent Pd and Re radii (1.39 + 1.51 = 2.90 Å). One carbene ligand and a diethyl ether molecule are disordered over two positions with occupancy ratios of 0.5:0.5 and 0.625 (15):0.375 (15) in 1. An unidentified solvent is present in compound 2. The given chemical formula and other crystal data do not take into account the unknown solvent molecule(s). The SQUEEZE routine [Spek (2015). Acta Cryst. C71, 9–18] in PLATON was used to remove the contribution of the electron density in the solvent region from the intensity data and the solvent-free model was employed for the final refinement. The cavity with a volume of ca 311 Å3 contains approximately 98 electrons.
Shapovalov S.S., Tikhonova O.G., Skabitskii I.V., Sakharov S.G., Simonenko N.P.
The reaction of (η5-C5H5)Ni(SIMes)Cl with n-propylmercaptane and NEt3 in CH2Cl2 affords the thiolate carbene nickel complex (η5-C5H5)Ni(SIMes)SnPr (I) (SIMes is 1,3-dimesitylimidazol-2-ylidene), which reacts with W(CO)5(THF) to form the heterometallic complex (η5-C5H5)Ni(SIMes)(μ2-SnPr)W(CO)5 (II). The reaction of complex I with (η5-С5H5)Mn(CO)2(THF) affords compound (η5-C5H5)Ni(SIMes)(μ2-SnPr)(η5-С5H5)Mn(CO)2 (III). The structures of compounds I, II, and III are determined by X-ray structure analysis (CIF file CCDC nos. 2024873 (I), 2024874 (II), and 2024875 (III)). According to the data of thermogravimetry and differential scanning calorimetry, the thermal decomposition of complexes II and III occurs stepwise in ranges of 101–500 and 119–550°С, and no ligand elimination is observed.
Shapovalov S.S., Skabitskii I.V.
The heterometallic complex (L1)Ru(κ2-O2CC5H4)Mn(CO)3(O2CC5H4)Mn(CO)3) (I) (L1 is the pivalate ligand) is synthesized by the reaction of the ruthenium(II) complex (L1)Ru(κ2-O2CCMe3)(O2CCMe3) with cymantrenylcarboxylic acid (HO2CC5H4)Mn(CO)3. The consecutive reactions of nickel acetate with cymantrenenecarboxylic acid and diimine 1,4-di-tert-butyl-1,4-diazabutadiene-1,3 affords the complex (L2)Ni(κ2-O2CC5H4Mn(CO)3)2 (II) (L2 = tBu–N=CH–CH=N–tBu). Complexes I and II are identified by the elemental and X-ray diffraction analyses data (СIF files CCDC nos. 2001354 (I) and 2001355 (II)).
Mayorova N.A., Modestov A.D., Grinberg V.A., Shiryaev A.A., Shapovalov S.S., Nickolsky M.S., Stolyarov I.P.
2021-02-01 citations by CoLab: 3 Abstract
Abstract A nanoscale bimetallic alloy catalyst PtFe/C is prepared by pyrolysis of the heterometallic platinum-iron carboxylate complex [PtFe(OAc)4]2O⋅4CH2Cl2 on Vulcan XC-72 carbon black. It is characterized by X-ray powder diffraction analysis, X-ray fluorescence spectroscopy, transmission electron microscopy, and electrochemical methods. Its activity in the oxygen reduction reaction (ORR) is tested in an aqueous H2SO4 electrolyte in model conditions, using a rotating disc electrode (RDE) technique, and in the membrane electrode assembly of the hydrogen-air single fuel cell. The synthesized catalyst is a tetragonal PtFe intermetallic compound with Pt:Fe = 1:1 atomic ratio. It is uniformly distributed over the carbon support with a predominant metal particle size between 3 and 6 nm. The ORR specific activity of the prepared alloy catalyst is superior to that of a commercial Pt/C E-Tek catalyst and, thus, the PtFe/C catalyst may be a promising cathode material for hydrogen-air fuel cells.
Torubaev Y.V., Skabitskii I.V., Minin V.V., Ugolkova E.A., Rusina P.V., Shapovalov S.S.
The 18-electron (η4-C4Me4)Co(CO)2TeI2Ph compound noticeably decomposes upon prolonged storage and also unusually transforms into the 17-electron (η4-C4Me4)CoI2(PhTeI) complex (I). The X-ray diffraction study of the molecular and crystal structures of complex I (CIF file CCDC no. 1991837) reveals interesting analogies with the molecular structures of the known metal complexes containing organotellurium halide ligands and with the crystal packing of the related one-component crystals of (η4-C4Me4)Co(СО)2TeI2Ph and (η4-C4Me4)Co(СО)2I and two-component crystals of (η4-C4Me4)Co(СО)2I–1,4-C6H4I2. An analysis of the crystal packing of molecules of complex I elucidates a new supramolecular synthone I···(η4-C4Me4) determining the structural motifs of self-assembly in complex I and related compounds (η4-C4Me4)Co(CO)2I, (η4-C4Me4)Co(CO)2I···1,4-C6H4I2, and (η4-C4Me4)Co(CO)2TeI2Ph. The EPR study of compound I shows that cobalt exists in the low-spin state with the total spin S = 1/2.
Melník M., Mikušová V., Mikuš P.
Inorganics Q2 Q2 Open Access
2025-01-25 citations by CoLab: 0 PDF Abstract
The structural aspects of homo-chromophores in Cu(I)(XXX) complexes, where X3 = N3, C3, Cl3, S3, P3, Br3, or I3, are analyzed in this study. These copper(I) derivatives crystallize in five distinct crystal systems as follows: rhombohedral (1 example), trigonal (1 example), orthorhombic (4 examples), triclinic (5 examples), and monoclinic (15 examples). The angular distortion from regular trigonal geometry increases in the following order: Cu(ClClCl) < Cu(NNN) < Cu(PPP) < Cu(BrBrBr) < Cu(III) < Cu(CCC) < Cu(SSS). For Cu(I)(XX) complexes, the deviation from linear geometry increases in the order: Cu(SeSe) < Cu(SS) < Cu(OO) < Cu(ClCl) < Cu(NN) < Cu(CC) < Cu(PP) < Cu(BrBr). The structural parameters of Cu(I)(XXX) are examined, discussed, and compared with those of homonuclear Cu(I)(XX) complexes.
Panina M.V., Ogarkova N.K., Dorovatovskii P.V., Sulimova O.V., Sosunov E.A., Cherkashina N.V., Makarevich J.E., Navasardyan M.A., Popova A.S., Yakushev I.A.
2024-11-29 citations by CoLab: 1
Lebedev V.T., Kulvelis Y.V., Rabchinskii M.K., Dideikin A.T., Shvidchenko A.V., Tudupova B.B., Kuular V.I., Yevlampieva N.P., Kuklin A.I.
2024-11-20 citations by CoLab: 0
Uvarova M.A., Shmelev M.A., Bekker O.B., Lutsenko I.A., Nefedov S.E., Eremenko I.L.
2024-10-04 citations by CoLab: 1 Abstract
Heterotrimetallic coordination polymers with metal core FeCu2, FeCu2Mn4, FeCo2Mn4, FeNi2Mn4 using functionalized cymantrene and ferrocene are synthesized and their antibacterial activity has been studied.
Thangaraj B., Monama W., Mohiuddin E., Millan Mdleleni M.
2024-10-01 citations by CoLab: 3 Abstract
Bioethanol is one of the most important bio-resources produced from biomass fermentation and is an environmentally friendly alternative to fossil-based fuels as it is regarded as renewable and clean. Bioethanol and its derivatives are used as feedstocks in petrochemical processes as well as fuel and fuel additives in motor vehicles to compensate for the depletion of fossil fuels. This review chronicles the recent developments in the catalytic conversion of ethanol to diethyl ether, ethylene, propylene, long-chain hydrocarbons, and other important products. Various heterogeneous catalysts, such as zeolites, metal oxides, heteropolyacids, mesoporous materials, and metal–organic frameworks, have been used in the ethanol conversion processes and are discussed extensively. The significance of various reaction parameters such as pressure, temperature, water content in the ethanol feed, and the effect of catalyst modification based on various kinds of literature are critically evaluated. Further, coke formation and coke product analysis using various analytical and spectroscopic techniques during the ethanol conversion are briefly discussed. The review concludes by providing insights into possible research paths pertaining to catalyst design aimed at enhancing the catalytic conversion of (bio)ethanol.
Wang Y., Jiang B., Zhao X., Chen Y., Pan X., Yu Q., Yao B.
Coatings Q2 Q2 Open Access
2024-08-02 citations by CoLab: 0 PDF Abstract
Phototransistors are three-terminal photodetectors that usually have a higher photocurrent gain than photodiodes due to the amplification of the gate electrode. In this work, a broad spectral phototransistor based on copper phthalocyanine (CuPc) and a Cs3Bi2I9 (CBI) heterojunction is fabricated by the full vacuum evaporation method. Due to the complementary UV–visible absorption of CuPc and CBI, the device exhibits superior performance under three different types of visible light illumination. The experimental results show that the structure of the organic/perovskite heterojunction active layer has the characteristics of good compatibility and a simple process. Meanwhile, by utilizing the superior light-absorption characteristics of perovskite materials and the strong exciton dissociation efficiency of a hetero-type heterojunction interface, the CuPc/CBI-PT exhibits a higher photoresponsivity, photosensitivity, specific detection rate, and lower operating voltage than the CuPc reference device. The stability test shows that the CuPc/CBI-PT can still obtain a 0.73 A/W photoresponsivity under 660 nm light illumination after being stored in the air for 360 h without any packaging. This indicates that the organic/perovskite heterojunction PT may be a good choice for the preparation of high-performance photodetectors.
Voznyakovskii A.P., Vozniakovskii A.A., Kidalov S.V.
2024-07-17 citations by CoLab: 0 Abstract
This review is concerned with the production of 2D graphene nanostructures (few-layer graphene; FLG) by our developed method for carbonization of biopolymers implemented in a self-propagating high-temperature synthesis (SHS) process. Here, we analyze and summarize the experimental and some theoretical results, which served us to design a phenomenological model for the SHS synthesis of 2D graphene structures. The main focus is on the results obtained over the last decade. The prospects for ongoing research into the carbonization of biopolymers are discussed. Particular attention is paid to those areas of research that are expected to be of most interest for the use of few-layer graphene in the near future.
Akdag A., Horoz S., Şahin Ö., Ekinci A.
2024-07-13 citations by CoLab: 1 Abstract
This investigation reported the performance of PEMFC cathode electrocatalysts produced from platinum, zirconium, and nickel alloys with varying atomic ratios. XRD, SEM, and EDX analyses were performed to investigate the structural and morphological properties of the synthesized catalysts. The studies evaluated electrochemical properties, specifically the ORR and the ECSA activity. Based on XRD data, the average crystallite diameters of Pt/C, PtZr2/C, and PtZr2Ni/C catalysts were calculated to be 4.95 nm, 4.33 nm, and 3.35 nm, respectively. Pt/C, PtZr2/C, and PtZr2Ni/C catalysts were used as cathode electrocatalysts in a single cell, and polarization curves were generated for each catalyst at temperatures of 40 °C, 50 °C, 60 °C, and 70 °C, respectively. It was determined that the PtZr2Ni/C and PtZr2/C catalysts had better performance than the Pt/C catalyst. Ozone, a powerful oxidizing agent, is another strategy for enhancing the cathodic process. The activity of PtZr2Ni/C catalyst used as cathode electrocatalyst increased with increasing cell temperature in both H2/O2 and H2/O3 usage, and the power density values at 70 °C cell temperature were calculated as 165.87 mWcm−2 and 242.08 mWcm−2, respectively.
Zafar M., Subramaniyan V., Tibika F., Tulchinsky Y.
2024-06-14 citations by CoLab: 1 Abstract
Incorporation of cationic ligands within pincer frameworks allowed to develop them from obscure peculiarities into a diverse class of ancillary ligands.
Wei Y., Li Y., Feng L., Xue Z., Wang A., Zhu G., Zhao L.
2024-06-01 citations by CoLab: 0 Abstract
Understanding the pH-dependent mechanism of metalloporphyrin-based composite electrocatalystic oxygen reduction reactions (ORRs) can provide the basis for rational porphyrin molecular design. Tunable ORR properties of a cobalt porphyrin-based composite catalyst aFP-TCoP/C is accomplished by adjusting the electrolyte pH values spanning from 0.7 to 13.7. The composite performs the best ORR reactivity in the pH13.7 electrolyte, exhibiting the most positive characterized potentials (the ORR reduction potential EORR of 0.76 V and the half-wave potential E1/2 of 0.80 V) and the smallest Tafel slope of 43.1 mV dec−1. Whilst the sample with the pH3.7 electrolyte displays quite negative reduction potentials and a large Tafel slope, it exhibits an electron transfer number of 3.84, which indicates a nearly 4-electron transfer selectivity. The findings provide a practical protocol for regulating the catalytic reactivity and selectivity of ORRs by adjusting the components of electrolytes.
Yakushev I.A., Dyuzheva M.A., Stebletsova I.A., Kornev A.B., Cherkashina N.V., Vargaftik M.N.
Abstract Heterometallic palladium(II) complexes with ferrocenecarboxylic acid FcCOOH were synthesized and structurally characterized for the first time. The reactions of mononuclear [Pd(Py) 2 (OOCMe) 2 ] and [Pd(Phen)(OOCMe) 2 ] complexes with FcCOOH were accompanied by easy displacement of acetate anions from the inner sphere by the ferrocenecarboxylate anions to give iron-containing molecular palladium complexes: three solvatomorphs of [Pd(Py) 2 (FcCOO) 2 ] with benzene ( I , II ) and dichloromethane ( III ); the use of [Pd(Phen)(OOCMe) 2 ] as the starting compound resulted in the formation of the heteroligand acetate ferrocenecarboxylate [Pd(Phen)(FcCOO) 2 Pd(Phen)(FcCOO)(OOCMe)] ( IV ). Fully substituted [Pd(Phen)(FcCOO) 2 ] ( V ) was prepared by successive treatment of palladium acetate [Pd 3 (OOCMe) 6 ] with FcCOOH and 1,10-phenanthroline. The structures of complexes I – V were studied by X-ray diffraction (CIF files CCDC nos. 2078399–2078403).
Fotović L., Bedeković N., Stilinović V.
2022-01-05 citations by CoLab: 13 Abstract
Six N-(4-halogenobenzyl)-3-halogenopyridinium cations were prepared by reacting meta-halogenopyridines (Cl, Br, and I) with (4-halogenobenzyl) bromides (Br and I) and were isolated as bromide salts, which were further used to obtain iodides and chlorides. Sixteen compounds (out of 18 possible cation/anion combinations) were obtained; two crystallized as hydrates and 14 as solvent free salts, 11 of which belonged to one isostructural series and 3 to another. All crystal structures comprise halogen-bonded chains, with the anion as an acceptor of two halogen bonds, with the pyridine and the benzyl halogen substituents of two neighboring cations. The halogen bonds with the pyridine halogen show a linear correlation between the relative halogen bond length and angle, which primarily depend on the donor halogen. The parameters of the other halogen bonds vary with all three halogens, indicating that the former halogen bond is the dominant interaction. This is also in accord with the calculated electrostatic potential in the σ-holes of the halogens and the thermal properties of the solids. The second isostructural group comprises combinations of the best halogen bond donors and acceptors, and features a more favorable halogen bond geometry of the dominant halogen bond, reaffirming its significance as the main factor in determining the structure.
2022-01-01 citations by CoLab: 1 Abstract
Использование высокодисперсных добавок как модификаторов структуры, в настоящее время является одним из эффективных инструментов повышения требуемых технико-эксплуатационных характеристик цементных композитов. Однако использование высокодисперсных порошков осложнено тем, что их частицы консолидированы в агрегаты. Тем самым не реализованным оказывается основное преимущество высокодисперсного порошка – возможность образовывать большее количество контактов при очень небольшом его содержании. Одним из перспективных путей тонкого диспергирования дисперсной фазы является использование ультразвуковой кавитации. Обработка ультразвуком не всегда обеспечивает требуемую эффективность, что связано с недостаточной информацией о влиянии условий, определяющих интенсивность ультразвукового излучения, на степень разрушения агрегатов. В связи с этим необходимым является определение факторов и условий ультразвукового воздействия, обеспечивающих эффективную дезагрегацию высокодисперсных порошков. В статье рассмотрены акустические потоки в жидкости, возникающие в результате кавитации и обеспечивающие интенсификацию массопереноса. Расчетным путем получены данные об эффективности влияния размера кавитационных пузырьков и крупномасштабных акустических течений на дисперсный состав порошка. Установлено, что эффективность дезагрегации высокодисперсных порошков можно повысить при обработке в условиях пониженного гидростатического давления.
Sergey Shakhov, Elena Rogova
2022-01-01 citations by CoLab: 1 PDF Abstract
Using finely dispersed mineral particles of various origins and morphologies offers a promising strategy in controlling the structure formation in cement composites. However, the use of such additives is hampered because those additives proved to be prone to consolidation into rather dense aggregates. Fine dispersion and disaggregation of powders is possible with the aid of cavitation ultrasonic treatment. However, the optimal conditions for such processing can not be established without conducting simulation studies. The purpose of the present study was the identification of ultrasonic-action factors and conditions ensuring an efficient disaggregation of finely dispersed powders of various origins and particle morphologies. In our study, we used diopside, granulated blastfurnace slag (GBS), wollastonite, ash, and calcium carbonate powders. It is found that the process of ultrasonic treatment of aqueous suspensions is accompanied not only by the dispersion of initial particles and aggregates but, also, by simultaneous formation of new aggregates. That is why the observed variations of the specific surface area and the optical density of powders can be attributed to the variation of the fractional composition of dispersed phase. The activating capability of a mineral additive is due to the fraction of the particles less than 1 μm in size exerting a key influence on the variation of the specific surface area of the powder. Our estimate of the energy efficiency of the cavitation disaggregation of powders during an ultrasonic treatment shows that the most energy-favorable one is the ultrasonic treatment lasting for 1–5 minutes, i.e. during the period of the first half-wave of the variation of the particle fraction less than 1 μm in size.
Shibatani A., Kataoka Y., Ura Y.
2021-11-12 citations by CoLab: 5 Abstract
The aerobic dehydrogenation of saturated carboxylic acids to α,β-unsaturated carboxylic acids proceeded over a simple Pd(OAc)2/pyridine catalyst system under 1 atm of O2.
Fotović L., Bedeković N., Stilinović V.
2021-11-08 citations by CoLab: 16 Abstract
We have performed a database survey and a structural and computational study of the potential and the limitations of halogenopyridinium cations as halogen bond donors. The database survey demonstrated that adding a positive charge on a halogenopyridine ring increases the probability that the halogen atom will participate in a halogen bond, although for chloropyridines it remains below 60%. Crystal structures of both protonated and N-methylated monohalogenated pyridinium cations revealed that the iodo- and bromopyridinium cations always form halogen-bonding contacts with the iodide anions shorter than the sum of the vdW radii, while chloropyridinium cations mostly participate in longer contacts or fail to form halogen bonds. Although a DFT study of the electrostatic potential has shown that both protonation and N-methylation of halogenopyridines leads to a considerable increase in the ESP of the halogen σ-hole, it is generally not the most positive site on the cation, allowing for alternate binding sites.
Virovets A.V., Peresypkina E., Scheer M.
2021-10-27 citations by CoLab: 77 Abstract
The review presents a bird-eye view on the state of research in the field of giant nonbiological discrete metal complexes and ions of nanometer size, which are structurally characterized by means of single-crystal X-ray diffraction, using the crystal structure as a common key feature. The discussion is focused on the main structural features of the metal clusters, the clusters containing compact metal oxide/hydroxide/chalcogenide core, ligand-based metal-organic cages, and supramolecules as well as on the aspects related to the packing of the molecules or ions in the crystal and the methodological aspects of the single-crystal neutron and X-ray diffraction of these compounds.
Ahamed M., Akhtar M.J., Khan M.A., Alhadlaq H.A.
Polymers Q1 Q1 Open Access
2021-09-30 citations by CoLab: 53 PDF Abstract
The efficacy of current cancer therapies is limited due to several factors, including drug resistance and non-specific toxic effects. Due to their tuneable properties, silver nanoparticles (Ag NPs) and graphene derivative-based nanomaterials are now providing new hope to treat cancer with minimum side effects. Here, we report a simple, inexpensive, and eco-friendly protocol for the preparation of silver-reduced graphene oxide nanocomposites (Ag/RGO NCs) using orange peel extract. This work was planned to curtail the use of toxic chemicals, and improve the anticancer performance and cytocompatibility of Ag/RGO NCs. Aqueous extract of orange peels is abundant in phytochemicals that act as reducing and stabilizing agents for the green synthesis of Ag NPs and Ag/RGO NCs from silver nitrate and graphene oxide (GO). Moreover, the flavonoid present in orange peel is a potent anticancer agent. Green-prepared Ag NPs and Ag/RGO NCs were characterized by UV-visible spectrophotometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and dynamic light scattering (DLS). The results of the anticancer study demonstrated that the killing potential of Ag/RGO NCs against human breast cancer (MCF7) and lung cancer (A549) cells was two-fold that of pure Ag NPs. Moreover, the cytocompatibility of Ag/RGO NCs in human normal breast epithelial (MCF10A) cells and normal lung fibroblasts (IMR90) was higher than that of pure Ag NPs. This mechanistic study indicated that Ag/RGO NCs induce toxicity in cancer cells through pro-oxidant reactive oxygen species generation and antioxidant glutathione depletion and provided a novel green synthesis of Ag/RGO NCs with highly effective anticancer performance and better cytocompatibility.
Nazarov I.V., Bermesheva E.V., Potapov K.V., Khesina Z.B., Il'in M.M., Melnikova E.K., Bermeshev M.V.
2021-09-01 citations by CoLab: 4 Abstract
New methylpalladium chloride complex with bulky N,N '-bis(1,2,3,4-tetrahydro-1-naphthyl)-substituted glyoxal diimine ligand was obtained. This complex was found to be an efficient catalyst for vinyl-addition polymerization of norbornene derivative and for polymerization of a diazoacetate, giving polycarbenes with side polar functionalities.
Podzorova L.I., Il’icheva A.A., Kutuzova V.E., Sirotinkin V.P., Antonova O.S., Baikin A.S., Konovalov A.A., Pen’kova O.I.
2021-08-24 citations by CoLab: 5 Abstract
Ceramic composite materials with a density not lower than 98.5% of the theoretical value were produced from powders containing 20 and 50 mol % corundum and tetragonal zirconia stabilized with ytterbia (3 mol %), [3Yb–TZP], modified with 1 mol % CaO, which were synthesized by hydrolysis sol–gel method. The use of ytterbium cation to stabilize tetragonal zirconia leads to the formation of two ZrO2 phases with different tetragonal symmetry. The introduction of CaO causes an increase in the content of the ZrO2 solid solution phase similar in composition to the cubic phase, which leads to lower strengths of doped composites in comparison with the initial ones.
Safronova T.V., Akhmedov M.M., Shatalova T.B., Tikhonova S.A., Kazakova G.K.
2021-08-24 citations by CoLab: 5 Abstract
Ceramics in the K2O–CaO–SO3–P2O5 system has been prepared from powder mixtures of potassium hydrogen sulfate KHSO4 and calcium hydroxyapatite Ca10(PO4)6(OH)2 at molar ratios KHSO4/Ca10(PO4)6(OH)2 = 2/1, 4/1, and 6/1. The powder mixtures were obtained in acetone under mechanical activation conditions using a planetary mill. After homogenization, the phase composition of powder mixtures included monetite CaHPO4, singenite K2Ca(SO4)2⋅H2O, and calcium hydroxyapatite Сa10(PO4)6(OH)2. After firing at 700–900°C the phase composition of ceramics manufactured from the powder mixtures included phases of potassium-substituted tricalcium phosphate Сa10K(PO4)7 and calciolangbeinite K2Ca2(SO4)3, as well as potassium sulfate K2SO4 at molar ratios KHSO4/Ca10(PO4)6(OH)2 = 4/1 and 6/1. Ceramic materials whose phase composition includes calciolangbeinite K2Ca2(SO4)3 and potassium-substituted tricalcium phosphate Сa10K(PO4)7 can be used as resorbable porous material for curing defects of bone tissue by regenerative medicine methods or as a matrix on designing luminescent/thermoluminescent materials. Ceramic materials in K2O–CaO–SO3–P2O5 system have been obtained for the first time, therefore, additional studies are necessary to determine the optimal phase ratio for the noted applications.
Cesari C., Shon J., Zacchini S., Berben L.A.
2021-07-14 citations by CoLab: 60 Abstract
In this review article, we discuss advances in the chemistry of metal carbonyl clusters (MCCs) spanning the last three decades, with an emphasis on the more recent reports and those involving groups 8-10 elements. Synthetic methods have advanced and been refined, leading to higher-nuclearity clusters and a wider array of structures and nuclearities. Our understanding of the electronic structure in MCCs has advanced to a point where molecular chemistry tools and other advanced tools can probe their properties at a level of detail that surpasses that possible with other nanomaterials and solid-state materials. MCCs therefore advance our understanding of structure-property-reactivity correlations in other higher-nuclearity materials. With respect to catalysis, this article focuses only on homogeneous applications, but it includes both thermally and electrochemically driven catalysis. Applications in thermally driven catalysis have found success where the reaction conditions stabilise the compounds toward loss of CO. In more recent years, MCCs, which exhibit delocalised bonding and possess many electron-withdrawing CO ligands, have emerged as very stable and effective for reductive electrocatalysis reactions since reduction often strengthens M-C(O) bonds and since room-temperature reaction conditions are sufficient for driving the electrocatalysis.
Panasyuk G.P., Kozerozhets I.V., Voroshilov I.L., Ivakin Y.D., Privalov V.I., Danchevskaya M.N.
2021-05-20 citations by CoLab: 6 Abstract
Thermodynamic characteristics and water evaporation mechanism from silica structure in temperature range 100–1000°С have been studied by thermogravimetry, mass spectrometry, 1Н and 29Si NMR. It has been shown that liquid, surface-bound, and molecular-dispersed water is present on the surface and in the bulk of silica particles. The role of different (ОН)n groups in the structural change of silica upon thermal and thermal steam treatment has been shown. A method for preparation of anhydrous silica used in the manufacture of high-quality quartz glass has been proposed.
See full statistics
Total publications
62
Total citations
289
Citations per publication
4.66
Average publications per year
2.82
Average coauthors
4.97
Publications years
2003-2024 (22 years)
h-index
9
i10-index
8
m-index
0.41
o-index
14
g-index
12
w-index
2
Metrics description

Fields of science

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General Chemistry, 39, 62.9%
General Chemical Engineering, 29, 46.77%
Inorganic Chemistry, 15, 24.19%
Physical and Theoretical Chemistry, 14, 22.58%
Materials Chemistry, 7, 11.29%
Materials Science (miscellaneous), 6, 9.68%
Condensed Matter Physics, 4, 6.45%
General Materials Science, 4, 6.45%
Organic Chemistry, 2, 3.23%
Biochemistry, 2, 3.23%
Catalysis, 1, 1.61%
General Physics and Astronomy, 1, 1.61%
Electrical and Electronic Engineering, 1, 1.61%
Mechanical Engineering, 1, 1.61%
Industrial and Manufacturing Engineering, 1, 1.61%
General Energy, 1, 1.61%
Pollution, 1, 1.61%
Building and Construction, 1, 1.61%
Civil and Structural Engineering, 1, 1.61%
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Journal not defined, 28, 9.66%
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Russia, 59, 95.16%
Country not defined, 2, 3.23%
Germany, 2, 3.23%
Switzerland, 2, 3.23%
France, 1, 1.61%
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Organization not defined, 28, 9.69%
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Citing countries

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Russia, 79, 27.34%
China, 32, 11.07%
Country not defined, 19, 6.57%
India, 18, 6.23%
Germany, 15, 5.19%
USA, 14, 4.84%
Italy, 9, 3.11%
Spain, 6, 2.08%
Czech Republic, 6, 2.08%
France, 5, 1.73%
Brazil, 5, 1.73%
Australia, 4, 1.38%
Indonesia, 4, 1.38%
Malaysia, 4, 1.38%
Turkey, 4, 1.38%
Switzerland, 4, 1.38%
South Africa, 4, 1.38%
Japan, 4, 1.38%
Iran, 3, 1.04%
Canada, 3, 1.04%
Chile, 3, 1.04%
United Kingdom, 2, 0.69%
Morocco, 2, 0.69%
Mexico, 2, 0.69%
Pakistan, 2, 0.69%
Poland, 2, 0.69%
Saudi Arabia, 2, 0.69%
Slovenia, 2, 0.69%
Austria, 1, 0.35%
Algeria, 1, 0.35%
Belgium, 1, 0.35%
Bulgaria, 1, 0.35%
Hungary, 1, 0.35%
Vietnam, 1, 0.35%
Djibouti, 1, 0.35%
Egypt, 1, 0.35%
Israel, 1, 0.35%
Colombia, 1, 0.35%
Netherlands, 1, 0.35%
Romania, 1, 0.35%
Slovakia, 1, 0.35%
Thailand, 1, 0.35%
Croatia, 1, 0.35%
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  • We do not take into account publications without a DOI.
  • Statistics recalculated daily.
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