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The Zn1.9Cu0.1SiO4 pigment was obtained by two variants of “soft” chemistry methods: using sol–gel synthesis in ethanol from TEOS and zinc and copper acetates and by coprecipitation of hydroxosilicate from an aqueous solution of zinc acetate and copper formate with sodium silicate. Thermal behavior of precursors, characterization of intermediate and final synthesis products were carried out by DSC, XRD, electron microscopy, colorimetry, IR, and UV-Vis-NIR spectroscopy. It is shown that the sequence of the phase formation of the synthesis product is determined by the characteristics of the initial solutions. It was established for the first time that when using the sol–gel method, the sequence of structural transformations is caused by the removal of the organic components and the destruction of the three-dimensional polymer network ≡Si–O–Si≡. In the coprecipitation method, crystallization occurs after the removal of the organic components and structurally bound water. It is shown that a feature of this method is the simultaneous crystallization of two structural modifications Zn1.9Cu0.1SiO4, the metastable phase transforms into the willemite structure with a further increase in the temperature. It was found that well-crystallized single-phase Zn1.9Cu0.1SiO4 samples synthesized by these methods can be obtained by annealing at 800 °C for 10 h. The differences in the shape of the samples depend on the morphological and dimensional variations of the particles. UV-Vis-NIR spectra show the broad band with a maximum at about 760 nm corresponding to two electronic d–d transitions: 2B1g → 2Eg and 2B1g → 2B2g.

Solution-combustion synthesis of NixCo3 – xO4 (x 0.9) led to an increase in reaction temperature and the formation (after annealing at 400°C) of non-stoichiometric spinels NixCo3 – xO4 (x < 1) with an admixture of double oxides NiyCo1 – yO (y = 0.71–0.77).

We consider the possibility for using the method of local mass relations in the region of superheavy elements with nuclear charge Z > 106. Binding energies, α-decay energies, and half-lives of α-decay are found for isotopes Z = 107–110 and N = 152–161, using formulas for estimating residual np-interaction.

Nanostructured hollow Co3O4 spheres are synthesized by ultrasonic spray pyrolysis. Nanocrystals forming the sphere structure have different sizes and packing density, depending on the synthesis conditions. The samples are studied by X-ray diffraction, scanning electron microscopy, low-temperature nitrogen adsorption, vacuum pycnometry, and Raman and X-ray photoelectron spectroscopies. The field and temperature dependences of magnetization show that the magnetic properties and the Neel temperature of Co3O4 hollow spheres are determined by the size and packing density of nanocrystals.

Using the ultrasonic spray pyrolysis method, a controllable process is realized for self-assembly of spherical BiFeO3 aggregates. Powders are obtained, which exhibit as the pronounced ferromagnetic properties (the coercive force Hc at 8.8 kOe and the residual magnetization Mp at 0.08 emu/g) characteristic of conventionally sol–gel produced BiFeO3 samples (Hc and Mp approaching zero). Various manifestations of ferromagnetism are discussed. It is found that the ultimate values of magnetic characteristics are related to destruction of the antiferromagnetic cycloid as the shells of hollow BiFeO3 spheres are formed. The aggregates thus formed may be considered as an advanced type of bismuth ferrite nanostructure with no coverage in the literature.

Different mass relations for estimating neutron–proton correlations are analyzed. The differences between the estimates indicate phenomenologocal distinction between the considered relations. Parametrization with a shell model is used to clarify the structure of different estimates and their correspondence to the real value of np-correlations.

Single-phase hollow bismuth ferrite microspheres ∼1 µm in diameter were synthesized by ultrasonic spray pyrolysis in a stream of air or argon. All the samples exhibited photocatalytic activity exceeding that of the standard TiO2 catalyst under UV irradiation. The samples synthesized in an argon stream exhibit catalytic activity under irradiation with a blue light. A comprehensive study showed that the appearance of the catalytic activity under the action of visible light was not associated with the powder particle morphology, oxygen defectiveness, and a change in the band gap width. An X-ray photoelectron spectroscopic study revealed decreased content of adsorbed oxygen on the surface of BiFeO3 synthesized in an argon stream. Possible mechanisms responsible for the appearance of the photocatalytic activity in the visible range are discussed.

Experimental data on the synthesis and properties of the solid solution BiFe1-xMnxO3 are given. The length of the solid solution (0 ≤ x ≤ 0,20) was established, the morphology of the particles and magnetic properties of the samples were investigated in dependence on the content of a dopant. Nonlinear concentration dependences of magnetic characteristics for BiFe1-xMnxO3 with a maximum at the manganese 5 — 7 mol. %. content were found.

Different estimates of the even–odd effect for the nuclear mass surface are discussed. The proton-number dependence of the energy gap is derived from the measured masses of the N = 20, 50, and 82 isotones with closed neutron shells. Its interrelation with the properties of external proton shells is demonstrated, and the effects of proton pairing are considered along with the microscopic nuclear structure.

Samples of BiFe0.93Mn0.07O3 with different specific surface area were synthesized for the first time by ultrasonic spray pyrolysis. The resulting powders consist of porous particles of a spherical shape of medium size ~0.5 μm and have record values of residual magnetization and coercive force. It is found that the magnetic properties of the porous powder particles are determined by the distortion of the crystal lattice and the presence of uncompensated magnetic moments of iron ions on the surface.

The photoluminescence properties of nanodimensional γ-Al2O3 produced by the thermolysis of aluminum hydroxoformate Al(OH)(HCOO)2 under different conditions have been studied. In the EPR spectrum of γ-Al2O3 prepared by thermohydrolysis, a low-field signal was detected, whose shape depends on the amount of sample. The data were interpreted assuming the existence of paramagnetic centers having no inversion center.

We study the consistency of local mass relation approach in its application to prediction of nuclear masses in the region of superheavy elements. Binding energy calculations are carried out for nuclei with [Formula: see text] using formulas for evaluation of residual [Formula: see text]-interaction. The results are found to be in good agreement with the experimental data AME2016. We also make predictions for characteristics of [Formula: see text]-decay in isotopes [Formula: see text]–106, [Formula: see text]–157.

New germanate ALa9(GeO4)6O2 (A = Li, Na, K, Rb, Cs) oxyapatites, showing promise as host lattices for phosphors with emission in the visible and infrared spectral ranges, have been obtained for the first time by ultrasonic spray pyrolysis. The discussion is focused on native defectiveness and optical properties of these compounds, depending on the nature of alkaline ions. Spray pyrolysis method was consciously used to obtain the compounds with intrinsic defects as confirmed by electron paramagnetic resonance. Reviewing available EPR data, the registered EPR response was assigned to the paramagnetic centers related to germanium tetrahedra embracing the oxygen vacancies. According to quantum-chemical calculations the oxygen-deficient centers in ALa9(GeO4)6O2 are presumably stabilized by antisite defects in the cation sublattice. Diffuse reflectance and pulse cathodoluminescence spectra of the compounds were investigated in detail, establishing a distinct dependence of optical properties on the type of alkaline ion. The observed optical absorption maxima at 275 and 370 nm were attributed to the F-like centers. The inverse dependence of luminescence intensity on the degree of defectiveness was interpreted on the assumption that these centers were involved in non-radiative energy relaxation.

A study was made of specific features of the formation of multifunctional ceramics La2 - xSrxNiO4 in thermal decomposition of carboxylate precursor complexes of several types. Pyrolysis of organics–salt composites is initiated by catalytic decarboxylation under the action of a d-element (Ni) to form metal oxides in the active state. It was shown that the synthesis of solid solutions La2 - xSrxNiO4 from carboxylate precursors occurs by single-stage thermolysis using any carboxylic acid or its salt.

Various estimates of the even-odd effect of the mass shell of atomic nuclei are considered. Based on the experimental mass values of the Ca, Sn, and Pb isotopes, the dependence of the energy gap on the neutrons number is traced and the relationship of this characteristic to the properties of external neutron subshells is shown. In nuclei with closed proton shells, effects directly related to neutron pairing and effects of nucleon shells are discussed., corrected typos

The transfer of alkali and alkaline earth metal ions and ammonium ions facilitated by the calixarenes 5,11,17,23-tetra(tert-butyl)-26,28-dihydroxycalix[4]-25,27-crown-5-ether, 5,11,17,23-tetra(tert-butyl)-26,28-di(ethoxycarbonylmethoxy)calix[4]-25,27-crown-5-ether, and 5,11,17,23-tetra(tert-butyl)-25,26,27,28-tetra(ethoxycarbonylmethoxy)-calix[4]arene was studied by voltammetry at the interface between two immiscible electrolyte solutions. The formal energies, transfer potentials, stoichiometry, and stability constants of the complexes were determined. The optimum conditions for determining the ammonium ion by voltammetry at the liquid-liquid interface were selected on the basis of these studies (the detection limit was 3.5 × 10−6 M). The ammonium ion determination showed selectivity relative to the sodium ion.

International audience; The results of an investigation of the structure, composition, and topography of the surface of buffer layers of CeO2, LaNiO3, and CeO2 + LaNiO3 on nonmagnetic textured NiCr9.2W2.4 substrates with a cube texture, which were prepared by pulsed laser deposition, are presented. The substrates with a buffer layer of this composition can be of interest for growing thin films and heterostructures of a wide class of oxide compounds, including superconductors of composition YBa2Cu3O7 − δ (123).

The transfer of aminoglycoside antibiotics streptomycin, kanamycin, and gentamycin induced by dibenzo-18-crown-6 is studied by voltammetry at the interface of two immiscible electrolyte solutions (ITIES). An assumption about the 1: 1 stoichiometry of the complexes formed is formulated. The method is proposed for use in the analysis of kanamycin and streptomycin in aqueous solutions. The optimal conditions of analysis of these aminoglycosides are found, the detection limits are 8.0 × 10−5 M for streptomycin and 2.0 × 10−4 M for kanamycin. The selectivity of streptomycin analysis by ITIES voltammetry in presence of potassium and sodium is studied. An amperometric ion-selective electrode is developed for the determination of streptomycin in drug formulations with a detection limit of 9.0 × 10−5 M.

A new thermal hydrolysis technique is proposed for synthesis of complex oxide ferrite spinels with the general formula MFe2O4, where M = Ni, Co, Cu, Mn, Zn, etc. The structural, morphological, and magnetic properties of powdered nickel ferrite NiFe2O4 obtained by the proposed technique are investigated.

Peculiarities of synthesis of nanocrystalline NiFe 2 O 4 powders by thermal decomposition of citrate precursors were investigated. It was found that the parameters of nanopowders are determined by the decomposition temperature and pH of the precursor media. The temperature and duration of the process of precursor decomposition are limiting factors for decrease of the grain size. An optimum relation between the limiting factors can be determined experimentally by variation of pH. Correlation between the synthesis parameters, particle size, and magnetic properties is discussed. It is shown that optimum magnetic and magnetostrictive properties were found for the bulk polycrystalline samples sintered using the powders obtained for pH 2.

A new method has been proposed for synthesizing spinel ferrites, i.e., thermal hydrolysis, which makes it possible to obtain a single-phase product of high purity for a short time. A polycrystalline sample of the CoFe2O4 composition has been prepared. The phase composition and morphology of the sample have been investigated and its crystal structure has been refined. The static magnetic characteristics have been measured.

Transfer of complexes of josamycin, spyramycin, and erythromycin with alkali and alkali-earth metals was studied using the method of voltammetry at the interface of two immiscible electrolyte solutions. Standard energies and standard transfer potentials of the formed complexes and also the values of their stability constants were determined. Stoichiometry of the complexes formed was determined. Experimentally obtained detection limits of these macrolide antibiotics in the organic phase are presented.

The possibility of synthesizing different crystalline modifications of alumina Al2O3 by combustion reactions of a mixture of aluminum nitrate with glycine has been analyzed. Aggregated powders of γ-Al2O3 that do not transform into the corundum structure after annealing at a temperature of 1000°C have been prepared. The influence of the synthesis conditions on the specific surface area, bulk density, porosity, and morphology of alumina particles has been investigated.

To establish the composition of the gentamicin complex (GNMC) of copper(II) in the polymer matrix of an ion-selective membrane (ISM), we investigated spectra of the ISM upon both incorporation of the GNMC and its complex with copper(II) by the IR spectrometry method. A number of spectral changes were revealed: the appearance and disappearance of some absorption bands and batho- and hypsochromic shifts accompanied by the substantial rearrangement of the bands’ intensities. The observed effects are indicative of the change of the distribution of the charge within the molecule, the formation of new bonds, and rotational transformation in the formation of a chelate cycle. This confirms not only the presence of a complex in the polymer matrix but also that its structure is identical to the one found in solution before.

The complexation of aminoglycoside antibiotics with metal cations was proposed as a derivatization method for the further determination of the complex obtained by potentiometry with ion-selective electrodes (ISE), voltammetry at the interface between two immiscible electrolyte solutions (ITIES), and spectrophotometry. It was shown by the spectrophotometric method that gentamicin formed a 1: 1 complex with copper(II). For the potentiometric determination of gentamicin, we obtained ionophores that were ion associates formed by the gentamicin complex of copper(II) and tetraphenylborate derivatives as counterions. The transfer of the gentamicin complex of copper(II) was studied voltammetrically at the ITIES. The results obtained indicate that l antibiotic gentamicin can be directly determined as a complex with copper(II) by potentiometric, voltammetric, and spectrophotometric methods.

On the basis of existent data we have carried out a comparative analysis of equilibriums of formation and distribution of metal complexes in extraction and ionometry with liquid and plasticized ion-selective electrodes. We have shown that electrode-active compounds are practically identical to compounds formed via extraction, and hence common behavioural patterns and clas-sification of ionometric systems correspond to the patterns found in extraction systems. Distribution processes, which take place in the ion-sensitive membrane, may be considered as being common for bi-phase systems, primarily extrationary, whereby reactions of formation and distribution take place. This approach provides well-grounded explanation for an array of experimentally de-termined facts: for instance association between sensitivity and selectivity of ion-selective electrodes and resistance of complexes, utilized as electrode-active compounds; hydrophobicity of complex and ligands; as well as the nature of the membrane dissolving agent.

A tetragonal (space group I4/mmm) solid solution La2-2x(Ca1-ySry)1 + 2xMn2O7 based on the Raddlesden-Popper phase (n = 2), which is formed by the simultaneous substitution of calcium in Ca3Mn2O7 by strontium and lanthanum, is synthesized by high-temperature annealing of La2O3, Mn2O3, CaCO3, and SrCO3 mixtures (1500°C, air). The concentration area of the solid solution in the scheme is a pentagon, whose corners correspond to the manganites Ca3Mn2O7, Ca0.75Sr2.25Mn2O7, La0.2Sr2.8Mn2O7, La1.6Sr1.4Mn2O7, and LaCa2Mn2O7.

The phase composition and structure of equilibrium LaMnO3-CaMnO3-SrMnO3 samples prepared at 1500°C in air are investigated. The results demonstrate that the system contains a broad region of La1 − x(Ca1 − ySry)xMnO3 perovskite-like solid solutions in which calcium and strontium cations substitute for lanthanum. The solid solutions have an orthorhombic (Pnma), rhombohedral \((R\bar 3c)\), or tetragonal (I4/mcm) structure, depending on the A-site cation composition and the nature of lattice distortions. The composition regions of these structures and two-phase regions are mapped out in the LaMnO3-CaMnO3-SrMnO3 phase diagram.

The phase formation in MO–LaMnO 3 –MnO 2 –Mn 3 O 4 systems (M=Ca, Ba) has been studied from 1400 to 1500°C in air. It was shown that the LaMnO 3 -based solid solution appears within a wide region due to vacancy formation in the cationic sublattice and heterovalent substitution. The regions of existence of the solid solutions La 1− x M x MnO 3 , M=Ca (0≤ x ≤0.70), Ba (0≤ x ≤0.45), and the solid solutions where cations in calcium manganites are replaced by lanthanum, namely, La 1− x Ca 1+ x MnO 4 (0.65≤ x ≤1.00) and La 2−2 x Ca 1+2 x Mn 2 O 7 (0.50≤ x ≤1.00), have been established. The formation of the solid solution La 1− x Ca x MnO 3 (0.90≤ x ≤1.00) was confirmed. Schematic phase diagrams of MO–LaMnO 3 –manganese oxides systems were constructed using the phase composition of the concentration regions bordering the solid solutions.

The correlation between methods of synthesis and magnetostrictive properties of ferrite materials is investigated. CoFe2O4 spinel ferrite was synthesized using three techniques: solid-phase reactions, thermal hydrolysis, and sol-gel. The effect of the method of synthesis on the magnetostrictive properties of spinel ferrite is demonstrated.

The processes involved in the solution combustion synthesis of α-Al2O3 using urea as an organic fuel were investigated. The data describing the influence of the relative urea content on the characteristic features of the combustion process, the crystalline structure and the morphology of the aluminium oxide are presented herein. Our data demonstrate that the combustion of stable aluminium nitrate and urea complexes leads to the formation of α-alumina at temperatures of approximately 600-800 °C. Our results, obtained using differential thermal analysis and IR spectroscopy methods, reveal that the low-temperature formation of α-alumina is associated with the thermal decomposition of an α-AlO(OH) intermediate, which was crystallised in the crystal structure of the diaspore. © 2012 Elsevier Ltd and Techna Group S.r.l.

The phase formation in MO–LaMnO 3 –MnO 2 –Mn 3 O 4 systems (M=Ca, Ba) has been studied from 1400 to 1500°C in air. It was shown that the LaMnO 3 -based solid solution appears within a wide region due to vacancy formation in the cationic sublattice and heterovalent substitution. The regions of existence of the solid solutions La 1− x M x MnO 3 , M=Ca (0≤ x ≤0.70), Ba (0≤ x ≤0.45), and the solid solutions where cations in calcium manganites are replaced by lanthanum, namely, La 1− x Ca 1+ x MnO 4 (0.65≤ x ≤1.00) and La 2−2 x Ca 1+2 x Mn 2 O 7 (0.50≤ x ≤1.00), have been established. The formation of the solid solution La 1− x Ca x MnO 3 (0.90≤ x ≤1.00) was confirmed. Schematic phase diagrams of MO–LaMnO 3 –manganese oxides systems were constructed using the phase composition of the concentration regions bordering the solid solutions.

Data on the frequency of intestinal infections caused by Klebsiella spp. in infants at the age of 1 month to 1 year and antibiotic resistance of K. pneumoniae and K. oxytoca isolates from newborns and infants aged 1 month to 1 year are presented. The frequency of the Klebsiella isolates from the newborns and infants at the age of 1 month to 1 year with acute intestinal infections amounted to 17.7 +/- 1.4 and 42.5 +/- 1.4 per cent, respectively. The majority of the clinical strains had a multiple resistance to 7-9 drugs. The overwhelming majority of the strains were sensitive to gentamicin, monomycin, kanamycin, neomycin and polymyxin B.