Subjects -> CHEMISTRY (Total: 986 journals)
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INORGANIC CHEMISTRY (45 journals)

Showing 1 - 34 of 34 Journals sorted alphabetically
Acta Polymerica     Hybrid Journal   (Followers: 9)
Additives for Polymers     Full-text available via subscription   (Followers: 20)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 9)
Advances in Polymer Technology     Open Access   (Followers: 13)
Bioinorganic Chemistry and Applications     Open Access   (Followers: 5)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 1)
Communication in Inorganic Synthesis     Open Access  
European Journal of Inorganic Chemistry     Hybrid Journal   (Followers: 10)
European Polymer Journal     Hybrid Journal   (Followers: 44)
High Performance Polymers     Hybrid Journal   (Followers: 1)
Indian Journal of Chemistry - Section A     Open Access   (Followers: 9)
Inorganic and Nano-Metal Chemistry     Hybrid Journal  
Inorganic Chemistry     Hybrid Journal   (Followers: 31)
Inorganic Chemistry Communications     Hybrid Journal   (Followers: 13)
Inorganic Chemistry Frontiers     Hybrid Journal   (Followers: 4)
Inorganic Materials     Hybrid Journal   (Followers: 5)
Inorganic Materials: Applied Research     Hybrid Journal   (Followers: 1)
Inorganica Chimica Acta     Hybrid Journal   (Followers: 6)
International Journal of Bio-Inorganic Hybrid Nanomaterials     Open Access   (Followers: 2)
International Journal of Inorganic Chemistry     Open Access   (Followers: 3)
JBIC Journal of Biological Inorganic Chemistry     Hybrid Journal   (Followers: 2)
Journal of Inorganic and Organometallic Polymers and Materials     Hybrid Journal   (Followers: 8)
Journal of Inorganic Biochemistry     Hybrid Journal   (Followers: 4)
Journal of Inorganic Chemistry     Open Access   (Followers: 3)
Journal of Polymers and the Environment     Hybrid Journal   (Followers: 1)
Journal of Progressive Research in Chemistry     Open Access  
Journal of Separation Science     Hybrid Journal   (Followers: 10)
Materials Today Chemistry     Hybrid Journal   (Followers: 2)
Open Journal of Inorganic Chemistry     Open Access   (Followers: 1)
Polymer Bulletin     Hybrid Journal   (Followers: 7)
Polymer Composites     Hybrid Journal   (Followers: 18)
Russian Journal of Inorganic Chemistry     Hybrid Journal  
Separation Science plus (SSC plus)     Hybrid Journal  
Zeitschrift für anorganische und allgemeine Chemie     Hybrid Journal   (Followers: 1)
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Russian Journal of Inorganic Chemistry
Journal Prestige (SJR): 0.325
Citation Impact (citeScore): 1
Number of Followers: 0  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1531-8613 - ISSN (Online) 0036-0236
Published by Springer-Verlag Homepage  [2537 journals]
  • Fluorination of α-Fe2O3 by NH4HF2 to Produce FeF3

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      Abstract: Fluorination of α-Fe2O3 by NH4HF2 has been analyzed in this study using simultaneous thermogravimetry and differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD). The results indicated that the mass ratio NH4HF2 to Fe2O3 has no influence on the fluorination process. The fluorination starts at room temperature, dominates at 175.6°C, and completes at 200°C with the formation of (NH4)3FeF6. With further heat-treatment, (NH4)3FeF6 progressively releases NH4F by the formation of NH4FeF4 at 258.1°C, then (NH4)0.18FeF3 at 320°C and finally FeF3 with minor FeF2 at 400°C. NH4F released during the decomposition of (NH4)3FeF6 will fluorinate the un-reacted Fe2O3.
      PubDate: 2021-12-01
       
  • First-Principles Calculations of Structural, Thermodynamic, and Elastic
           Properties of Lead Chalcogenides PbX (X = S, Se, and Te) in NaCl (B1)
           Phase

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      Abstract: The structural, thermodynamic, and elastic properties of the cubic type B1 (NaCl) phase for the lead chalcogenides PbS, PbSe, and PbTe were studied using DFT calculations. The exchange-correlation functional used in this study is the generalized gradient approximation associate by Perdew–Burke–Ernzerhof (GGA-PBE). The structural properties of these compounds have been calculated and their values have been found in good agreement with the experimental results. The stability of these materials is discussed on the basis of the calculated elastic constants Cij, in which the results indicate that the studied compounds are stable and the estimated values are in excellent agreement with the experimental data. The thermodynamic properties of PbX materials have also been evaluated. The influence of temperature and pressure upon the bulk modulus (B), expansion coefficients (α), and heat capacities Cv and Cp were estimated and discussed. The heat capacity Cv reaches up to 49 J/mol K for different materials studied. The influence of temperature on the Cp was also investigated for different pressures (from 0 to 12 GPa) and the results obtained were analyzed.
      PubDate: 2021-12-01
       
  • Tuning the Gas Sensing Properties of C20 towards H2S and O3 by Doping and
           External Electric Field

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      Abstract: In the present work, a theoretical study based on density functional theory (DFT) has been carried out to investigate the effects of external electric field and doping with B, N, Cr, Ni, and Cu on the gas sensing properties of C20 towards H2S and O3. For this purpose, the new hybrid potential of density functional theory was used. Natural bonding orbital and density of states analysis was applied to obtain a comprehensive interpretation of the electronic properties of C20. This study revealed a high adsorption of O3 on the outer surface of C20. The study also showed that the adsorption of H2S on the surface of C20 is unfavorable. However, the two strategies of applying an external electric field and doping with elements B, N, Cr, Ni, and Cu successfully increased the binding energy between H2S and the adsorbents. The results showed that the adsorption of O3 on the adsorbents in the presence of the electric field and the doped structures falls in the range of chemisorption, while the H2S adsorption is in the range of physisorption.
      PubDate: 2021-12-01
       
  • Solubilities, Densities, Refractive Indices, and pH Values of Ternary
           Systems (LiCl + Li2CO3 + H2O) and (Li2SO4 + Li2CO3 + H2O) at 288.15 K

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      Abstract: Solid-liquid phase equilibria of the ternary systems (LiCl + Li2CO3 + H2O) and (Li2SO4 + Li2CO3 + H2O) are very important for the separation of lithium salts from the salt lake brines. In this paper, the experimental solubilities, densities, refractive indices, and pH values of the ternary systems (LiCl + Li2CO3 + H2O) and (Li2SO4 + Li2CO3 + H2O) at 288.15 K and 0.1 MPa were investigated by means of isothermal solution method. In ternary system (LiCl + Li2CO3 + H2O), there are one eutectic point and two crystallization regions corresponding to Li2CO3 and LiCl·2H2O. Lithium chloride has a strong salting-out effect to lithium carbonate. The crystallization region of Li2CO3 was the largest, indicating Li2CO3 could be easily crystallized and separated from brines. In ternary system (Li2SO4 + Li2CO3 + H2O), there are one eutectic point and two crystallization regions corresponding to the large area of Li2CO3 and the relative small area of Li2SO4·H2O, respectively. The variation trend of solution densities, refractive indices and pH values in the two ternary systems are similar and change regularly with the increasing of the concentration of lithium sulfate or lithium chloride. The calculated values of density and refractive index using empirical equations for the two ternary systems are in good agreement with the experimental values.
      PubDate: 2021-12-01
       
  • Efficient Process of ALD CuO and Its Application in Photocatalytic H2
           Evolution

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      Abstract: As a cost-effective material, CuO has been widely used in many emerging fields. The synthesis method plays a key role in the performance of the material. Atomic layer deposition (ALD) has been developed as a precise technique to deposit materials with great control at atomic scale. Herein, an efficient process of ALD CuO is reported by using [Cu(sBu-amd)]2 and O3 as precursors. CuO films can be deposited on SiO2 substrates with typical self-limiting growth behaviors at 120–220°C. Notably, the growth rate of the CuO films is reach up to 2.5 Å/cycle, which is 6~12 times more than the available value. This remarkably high efficiency is the critical factor to promote the large-scale applications of ALD CuO materials. Furthermore, CuO is deposited on TiO2 nano-particles (forming CuO/TiO2 composite) using this ALD process to evaluate its performance for H2 evolution. The 0.37 wt % CuO/TiO2 composite (120 cycles CuO/TiO2) can achieve a H2 evolution rate of 3995 μmol g–1 h–1, which is nearly 200 times larger than pure TiO2.
      PubDate: 2021-12-01
       
  • Copper(II) Complex of
           Bis(1',3'-Hydroxymethyl)-Spiro-(Fluorene-9,4'-Imidazolidine)-2',5'-Dione,
           Cytotoxicity and Antibacterial Activity of Its Derivative and Crystal
           Structure of Free Ligand

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      Abstract: The aims of the present study were to synthesize, elucidate the structure and investigate the biological properties of substituted fluorenylspirohydantoins: Cu(II)L1 complex of 1,3-dihydroxymethyl-(9'-fluorene)-spiro-5-hydantoin (bis(1',3'-hydroxymethyl)-spiro-(fluorene-9,4'-imidazolidine)-2',5'-dione) (L1) and 4'-bromo-(9'-fluorene)-spiro-5-hydantoin (4'-bromо-spiro-(fluorene-9,4'-imidazolidine)-2',5'-dione) (L2). Based on the experimental data, the most probable structure for the copper(II) complex was suggested with one deprotonated OH group in C-7 position of two ligand L1 molecules and O4-atom and formed six-membered chelate rings CuOCNCO–[CuL1-H)2]. We determined their cytotoxic effects on the tumor human cell line A2058 by WST-1 assay (Roche Applied Science). The antimicrobial activity against both Gram-positive, Gram-negative bacteria and the yeast Candida albicans was studied additionally. The structures of the new compounds were discussed based on the performed spectroscopic measurements (UV-Vis, IR, Raman, 1H- and 13C NMR spectroscopy) and the single-crystal X-ray diffraction method for 1,3-dihydroxymethyl-(9'-fluorene)-spiro-5-hydantoin. The compound was crystallized in monoclinic crystal system and P21/c space group.
      PubDate: 2021-12-01
       
  • Phase Equilibria in the Quinary Na, Mg//Cl, SO4, NO3–H2O System at
           25°C

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      Abstract: Phase equilibria in the quinary Na, Mg//Cl, SO4, NO3–H2O system at 25°C were determined and a total phase equilibria diagram of the system was constructed employing the translation method. There are eight invariant points, 25 monovariant curves, and 27 divariant fields in this system. Eighteen of the latter curves form due to the extension of quaternary points into overall composition while the other seven curves form between the quinary points. Diagram was fragmented into separate regions. The part of the system saturated with Halite agrees well with available literature data.
      PubDate: 2021-12-01
       
  • Photocatalytic Activity Enhancement in Methylene Blue Degradation by
           Loading Ag Nanoparticles onto α-Fe2O3

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      Abstract: Modified alpha iron(III) oxide (α-Fe2O3) used as visible light-driven photocatalysts were successfully synthesized with different ratios of silver nanoparticles (AgNPs) by coupling a hydrothermal method with an impregnation method. The samples were characterized by their physicochemical properties using X-ray powder diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, UV-visible diffuse reflectance spectroscopy, Brunauer–Emmett–Teller (BET) specific surface area and photoluminescence spectroscopy (PL). The X-ray powder diffraction results indicated that all the samples were in the rhombohedral (hexagonal) phase of α-Fe2O3. The photocatalytic activities of Ag-loaded α-Fe2O3 were evaluated through the mineralization of methylene blue (MB) under visible light illumination. The α-Fe2O3 photocatalytic results showed that loading with Ag nanoparticles could improve the photocatalytic activities effectively. It was found that 5.0 wt % Ag-loaded α-Fe2O3 was a better photocatalyst than others under the same reaction conditions. Its efficiency was 68.6% at 150 min at a kinetic rate constant (k) of 7.9 × 10−3 min−1.
      PubDate: 2021-12-01
       
  • Study of Protonation of the Monocarbonyl Derivative of the
           closo-Decaborate Anion [B10H9CO]–

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      Abstract: Currently, the chemistry of carbonyl derivatives of the closo-borate anions is actively developing. It is of great interest to obtain protonated complexes of these types of clusters for further directed functionalization. The aim of this study is to develop an approach to the preparation of the protonated complex of the monocarbonyl derivative [B10H9CO⋅Hfac]0. In the course of the work, the target complex has been obtained by protonation of the [B10H9CO]– anion with an excess of trifluoromethanesulfonic acid CF3SO3OH. In this reaction, the boron cluster is quantitatively protonated. When a base is added, the protonation process becomes reversible.
      PubDate: 2021-12-01
       
  • Synthesis of Nanoscale WO3 by Chemical Precipitation Using Oxalic Acid

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      Abstract: The synthesis of nanoscale WO3 by chemical precipitation with oxalic acid was studied. The obtained powder was characterized by IR-spectroscopy and powder X-ray diffraction, while its thermal behavior was investigated by simultaneous TGA/DSC analysis. It was found that before heat treatment, the precipitate is a mixture of WO3⋅2H2O and tungsten oxalate. The heat treatment at 400°C results in oxalate decomposition, while treatment at 500°C gives single-phase WO3 with monoclinic crystal structure (mean CSR of 36 ± 4 nm, particle length of 50 ± 5 nm, and particle width of 40 ± 4 nm). The electron work function of the surface of prepared WO3 particles in air was measured using Kelvin-probe force microscopy. It was shown that chemical precipitation of tungsten(VI) oxide using oxalic acid is a promising method for producing the corresponding nanopowder.
      PubDate: 2021-12-01
       
  • Theoretical Modeling of Exo- and Endohedral Hydrogenation Reactions of the
           Doped Magnesium Cluster Mg17Ni

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      Abstract: Based on DFT and IRC calculations, the potential energy surfaces of the hydrogenation channels of the Mg17Ni cluster have been compared. In “exohedral” channels, sorption, post-sorption, and migration processes of H atoms are assumed to be localized on the cage surface with maximum barriers of ~14 kcal/mol. In the “endohedral” channel with a barrier of ~6 kcal/mol, the key role is played by transformations of the planar configuration of the surface NiH4 group into a tetrahedral one, in which two of its lower H atoms migrate through the inner cavity and enter surface positions, inverting through the square and adjacent triangular faces into the lower half of the cage. The course of the latter process requires milder conditions in comparison with exohedral channels.
      PubDate: 2021-12-01
       
  • Effect of the 3d Electron Self-Interaction Correction on the Electronic
           and Magnetic Properties of CoGeN2, CrGeN2, MnSiN2, and MnGeN2

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      Abstract: The electronic structure has been calculated for new CoGeN2, CrGeN2, MnSiN2, and MnGeN2 crystals with a chalcopyrite structure in the antiferromagnetic (AFM) and ferromagnetic (FM) phases. It has been found that the AFM state is energetically favorable for all four materials. For the first time, the electronic properties of CoGeN2 and CrGeN2 have been studied using two exchange-correlation functionals, namely, GGA-PBE and PBE0. The second approach differs from the first one in that it includes the correction for the Coulomb self-interaction error (SIE) for strongly correlated 3d electrons. For example, without applying this correction, the bandgap in CoGeN2, MnSiN2, and MnGeN2 in the AFM phase is 0.11, 1.45, and 0.91 eV, and with inclusion of the SIE correction, it is 1.46, 3.47, and 1.37 eV, respectively. Without the SIE correction, CoGeN2 has metal properties for both spin orientations, and when the SIE correction is applied, it is a direct-gap semiconductor with a bandgap of 1.38 eV for spin up and 1.77 eV for spin down. The crystals under consideration are promising materials for magnetoelectronic applications.
      PubDate: 2021-12-01
       
  • Thermodynamic Characteristics of Zinc Niobates Zn3Nb2O8, ZnNb2O6, and
           Zn2Nb34O87. p–x Diagram of the ZnO–Nb2O5 System

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      Abstract: Vapor formation in the ZnO–Nb2O5 system in the range 1223–1465 K was studied by Knudsen effusion mass spectrometry. Over the entire range of condensed phase compositions, the saturated vapor above the system consists of zinc atoms, oxygen molecules, and a small amount of ZnO molecules. The absolute component partial vapor pressures and activities were calculated. The р–х section of the global р–Т–х phase diagram at 1353 and 1443 K was plotted. The second-law and third-law values were determined of the standard enthalpies of selected heterophase reactions and the standard enthalpies of formation zinc niobates: \({{\Delta }_{f}}H_{{298}}^{^\circ }\) (Zn3Nb2O8) = –2992.0 ± 30.2 kJ/mol, \({{\Delta }_{f}}H_{{298}}^{^\circ }\) (ZnNb2O6) = –2292.4 ± 19.9 kJ/mol, and \({{\Delta }_{f}}H_{{298}}^{^\circ }\) (Zn2Nb34O87) = –33056.1 ± 15.0 kJ/mol, and their enthalpies of formation from simple oxides: (Zn3Nb2O8) = –50.0 ± 20.0 kJ/mol, (ZnNb2O6) = –40.5 ± 15.0 kJ/mol, and (Zn2Nb34O87) = –90.9 ± 15.0 kJ/mol.
      PubDate: 2021-12-01
       
  • Formation of NiMoO4 Anisotropic Nanostructures under Hydrothermal
           Conditions

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      Abstract: —The synthesis of NiMoO4 hierarchical nanostructures using the hydrothermal method has been studied. The decomposition of NiMoO4·xH2O crystalline hydrate formed during the synthesis has been studied using synchronous thermal analysis upon heating in a stream of air and argon. According to X-ray diffraction as well as scanning and transmission electron microscopies, the proposed conditions allow one to synthesize single-phase nanosized (average CSR size of about 25 ± 2 nm) nickel(II) molybdate, which has a spinel-type monoclinic structure (space group C2/m) without impurity inclusions.
      PubDate: 2021-12-01
       
  • Hydrothermal Synthesis of SmPO4 Whiskers: Effect of Particle Morphology on
           the Spectral and Thermodynamic Characteristics

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      Abstract: Samarium orthophosphate, having particles of an elongated prismatic shape with pronounced anisotropy, was obtained by a hydrothermal synthesis in “soft” conditions, varying the temperature of 160–200°C and the processing time of 55–100 hours. The influence of particle shape on the thermodynamic, spectral and structural characteristics of samarium orthophosphate was evaluated. The distortions of the PO4 tetrahedra and anharmonic vibrations in anisotropic whisker-like crystals were observed by means of X-ray diffraction and infrared studies. The heat capacity and thermodynamic functions of SmPO4 whiskers were determined in the temperature range from 5 to 1200 K. These results can significantly expand existing structural and spectral studies aimed at assessing the effect of particle habitus on the properties of materials.
      PubDate: 2021-12-01
       
  • Cerium(IV) Orthophosphates (Review)

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      Abstract: The review analyzes the data on the composition, structure, and properties of amorphous and crystalline cerium(IV) orthophosphates published between 1882 and 2020. The review includes information on Ce(IV) complexation in aqueous solutions, formation conditions and characteristics of amorphous inorganic and organo-inorganic cerium(IV) hydrogen orthophosphates, and structural diversity of crystalline cerium(IV) orthophosphates. Formation conditions and structure of the closest chemical analogs of cerium(IV) orthophosphates, Group IV metal and actinide (thorium and uranium) orthophosphates, have been compared for the first time; the comparison provided a basis to assess the possibilities to prepare isostructural cerium(IV) compounds unknown to date.
      PubDate: 2021-12-01
       
  • Textured Barium Hexaferrite Films on Silicon Substrates with Aluminum
           Oxide and Titanium Oxide Barrier Layers

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      Abstract: The possibility of synthesizing textured barium hexaferrite films on silicon wafers with Ti, Al2O3/Ti, or Al2O3/TiO2 barrier layers was studied. X-ray diffraction (XRD) showed that, after crystallization annealing, the hexaferrite phase with the (00l) preferred orientation was formed only when there was contact between BaFe12O19 and Al2O3. The hexaferrite microstructure in these samples, according to atomic force microscopy (AFM), is represented by rounded grains, which are typical of films where the hexagonal axis is perpendicular to the surface plane. Titanium in a BaFe12O19/Al2O3/Ti sample was partially oxidized during the synthesis. This process and the associated phase transformations in TiO2 are assumed to induce mechanical stress in the structure and, as a consequence, the formation of macroscopic defects (bulges). Complete pre-oxidation of the titanium film produced a textured BaFe12O19 structure without macroscopic defects.
      PubDate: 2021-12-01
       
  • Crystal Chemistry and Magnetic Properties of Polycrystalline Spinel
           Ferrites Li0.33Fe2.29Zn0.21Mn0.17O4

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      Abstract: Polycrystalline spinel ferrites of composition Li0.33Fe2.29Zn0.21Mn0.17O4 have been synthesized by the ceramic method at sintering temperatures of 950, 1000, 1050, and 1100°С. The crystal structure of the resulting samples has been studied by X-ray powder diffraction, and the chemical composition of the ferrites has been refined by the secondary ion mass spectrometry. Magnetic characteristics of the samples have been measured on an MK-3E magnetic measuring device. Room-temperature Mössbauer spectra have been recorded on an Ms-1104 Em spectrometer. The cation distribution in the crystal lattice of the resulting ferrites has been established; crystal chemical formulas have been calculated for each sintering temperature. The Mössbauer spectra of all the obtained samples are modeled by five sextets, which is explained by the appearance of nonequivalent Fe3+ ions in octahedral and tetrahedral positions, differing in the composition of the second coordination sphere. Combinations of lithium, manganese, and zinc ions in the nearest cationic environment of octahedral iron ions have been determined on the basis of a model that takes into account the peculiarities of changes in the Mössbauer parameters with an increase in the sintering temperature of ferrites. It has been shown that Mössbauer spectroscopy in combination with X-ray powder diffraction and magnetometry provides efficient control of the phase composition, cation distribution, and magnetic properties in substituted ferrites.
      PubDate: 2021-12-01
       
  • Structures of Coordination Polymers of Zinc, Cobalt(II), and Manganese(II)
           Trifluoroacetates with 4,4'-Dipyridyl

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      Abstract: Thermal heating of crystals [Zn3(µ-OH2)2(µ-OOСCF3)4(OOCСF3)2(OH2)2][µ-O(CH2CH2)2O)], Co3(µ-OOCF3)4(µ-OH2)2(OOCF3)2[O(CH2CH2)2O]2(ОН2)2, and [Mn2(µ-OOСCF3)3(OOCСF3) (OH2)][µ-O(CH2CH2)O]2 in vacuum (180°С) leads to the formation of powders, the dissolution of which in THF followed by slow diffusion of a solution of 4,4'-dipyridyl (dipy) in THF results in the formation of 1D coordination polymer [Zn(OOCCF3)2(dipy) · 0.5THF]n with a zigzag geometry and 3D coordination polymers {Co[(OOCCF3)(dipy)]2}n and {Mn[(OOCCF3)(dipy)]2 ⋅ 3THF}n, the latter containing solvate molecules THF in pores. The obtained compounds have been studied by chemical analysis, IR spectroscopy, and X-ray diffraction.
      PubDate: 2021-12-01
       
  • Influence of Carbon Deficiency and Hafnium Oxide Doping on Reactive Spark
           Plasma Sintering of the Ta2O5–C System

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      Abstract: ― Features of the application of the method of spark plasma sintering, as one of the most effective and promising for the manufacture of super-refractory oxygen-free ceramics, have been studied for the reactive consolidation of highly dispersed powder Ta2O5–HfO2–C with a carbon deficiency in comparison with that necessary for the synthesis of metal monocarbides. The initial powder has been obtained by the sol-gel method with a calculated ratio n(Ta) : n(Hf) = 9 : 1, confirmed experimentally using the EDX method. Spark plasma sintering experiments of the resulting system have been carried out in a dynamic vacuum at a pressure of 25 MPa and temperatures of 1600 and 1700°C (higher temperatures led to the outflow of molten oxides from the molds before the beginning of carbothermal synthesis of TaC–HfC). The presence of tantalum subcarbide Ta2C in the obtained ceramic is more advantageous than the oxide impurities and the formation of which under the selected conditions has been predicted by thermodynamic calculations. Its absence can be explained by the fact that equilibrium is not achieved when heating, holding, and cooling the sample.
      PubDate: 2021-12-01
       
 
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