Solid-phase synthesis of ytterbium zirconate using mechanical activation

Nanocrystalline ytterbium zirconate Yb4Zr3O12 was prepared by the solid-phase method using mechanical activation of stoichiometric mixture of zirconium and ytterbium oxides. Mechanical activation was carried out in an AGO-2 centrifugal-planetary mill at a centrifugal factor of 40 g for 10 min. The processes occurring during the calcination of the mechanically activated mixture of ytterbium and zirconium oxides in the range from 600 to 1300 °C were investigated using X-ray phase analysis, IR spectroscopy, and complex thermal analysis.

Adducts of Lower Fullerenes and Amino Acids: Synthesis, Identification, and Quantum-Mechanical Modeling of Their Physicochemical Properties

Different ways of synthesizing bis-, tris-, and octakis-adducts of C60 and C70 lower fullerenes are considered, and their yield and purity are described. The adducts are identified by physicochemical means: elemental analysis, IR, electron spectroscopy, Raman spectroscopy, HPLC, mass spectrometry, and complex thermal analysis. Their physicochemical properties are modeled using computers, density functional theory, and molecular dynamics at the atomic-molecular level.

Рhysical and chemical analyses of the adsorption capacity of transcarpathian clinoptilolite

The IR spectroscopy and complex thermal analysis were used to analyze the adsorption capacity of Transcarpathian clinoptilolite, both naturally occurring and activated, relative to water vapor. It was found that activation of clinoptilolite with an H2SO4 25 %-solution causes dealumination and the appearance of additional adsorption centers, allowing maximum adsorption of water vapor. Activation with a 5 % solution of HCl at the 1:10 solid-liquid ratio ensures the significant dealumination of the mineral with no breakdown of its structure and the occurrence of transient pores and macropores in this mineral. Due to such activation clinoptilolite is far more able to absorb molecules of the green dye.

Synthesis of Epoxyperoxides and Peroxide Derivatives of -D-Galactopyranose Based Thereon

New epoxide-containing peroxides have been synthesized via the interaction between epichlorohydrin and ditertiary -hydroxyalkyl peroxides. The effect of reaction conditions on both the yield and composition of the reaction products has been established. Through the reactions of either the synthesized epoxide-containing peroxides with 1,2;3,4-di-O-isopropylidene--D-galactopyranose or 6-O-glycidyl-1,2;3,4-di-O-isopropylidene--D-galactopyranose with the -hydroxyalkyl peroxides, new peroxide derivatives with ditertiary and primary-tertiary peroxide groups have been synthesized successfully. The decomposition of the developed substances has been studied by complex thermal analysis and the kinetic parameters of the thermolysis have been determined.

Thermal Stability of Inorganic Pigments Synthesized from Galvanic Sludge

Pigments used in ceramic glazes have been obtained by chromium ions extraction from galvanic sludge and their precipitation as barium chromate and lead chromate from technological solutions. The chemical composition was determined by XRF method. Complex thermal analysis TG-DSC, XRD and SEM methods have been used for microstructural characterization and thermal treatment behaviour evaluation, in order to establish the compatibility with the ceramic matrix. XRD spectra have highlighted only lead chromate specific interferences in the monoclinic phase and barium chromate in the orthorhombic phase, suggesting an advanced degree of purity. Weight losses of 2.2% for barium chromate and 3.1% for lead chromate have been recorded on the TG curve at 800�C. As a result of thermal treatment, barium chromate has changed its colour from yellow to green.

Physical-Chemical Studies and Evaluation of the Suitability of Chernoyarskoe Deposit’s Diatomite for the Synthesis of Foam Glass

The macro- and microstructure is investigated by microscopic analysis methods. The elemental, granulo-metric and mineralogical composition of diatomite of the Chernoyarskoe deposit is determined. As a result of complex thermal analysis, using a differential scanning calorimeter, intervals of continuous dehydration of diatomite were studied, as well as polymorphic transformations of quartz and other minerals. Physical-chemical methods of research have discovered that diatomite of the Chernoyarskoe deposit contains amorphous silica, quartzite, clay impurities, opal and minor amounts of calcite, mica, zeolite, and so this diatomite is a promising raw material for the synthesis of foam glass.

Fluorescence, Biological Activity and Spectroscopic Studies of Azo-linked Schiff Base Ligand Type (ONO) and Its Complexes with CrIII, CoII NiII and CdII Ions

The precursor [W] [2-(2-(naphthalen-5-yl) diazenyl)-4-amino-3-hydroxynaphthalene-1sulfonic acid] was synthesized from reaction of diazonium salt with 1-amino-2-naphtol-4sulfonic acid. Then the tridentate Schiff base ligand type ONO was synthesized from the reaction of the precursor with salicyaldehyde in 1:1 mole ratio to produce the ligand H2L [2-(2-(naphthalen5-yl) diazenyl)-4-(2-hydroxynaphthalen-3-yl)methyleneamino)-3-hydroxy salicyalene-1-sulfonic acid],the reaction achieved in methanol as a solvent under reflux. Spectroscopic methods IR, U.V, 1H,13C-NMR was used to characterize the ligand. Complexes of [CrIII, CoII, NiII and CdII] ions were also prepared through reaction of ligand with metal salts in 2:1 mole ratio at reflux, using KOH as a base, ethanol as a solvent. Chloride content, molar conductivity and melting point measurements along with I.R and U.V-Vis, atomic absorption (A.A) spectroscopy were used to characterize the complexes.1H-NMR spectroscopy was used to characterize Cd complex. Thermal analysis was used to insure the presence of crystallized H2O molecule in the complexes structure. The following formula was proposed for Cr complex: K[Cr(L)2]. H2O, while CoII, NiII and CdII complexes have the K2[M(L)2].H2O formula. The biological activity of the prepared compounds was studied. Fluorescence properties of the prepared compounds were studied (at room temperature) which indicate that the ligand may behave as strong fluorescent emitter. The complexes also showed fluorescence characteristic with the ligand. The ligand revealed high relative intensity and its fluorescence peak were also shifted to the lower or higher wavelength when compared with the complexes.

Skrew Rolling of Balls in Multiple Helical Impressions

This paper presents results of theoretical and experimental research on skew rolling process of balls with diameter ;30 mm in multiple helical tools. Numerical analysis of the process was conducted basing on finite element method (FEM), using the commercial software Simufact Forming in version 10.0. Simulations were made in the three-dimensional state of strain with consideration of complex thermal analysis, due to which progression of the products shape was determined. Distributions of strains and temperatures as well as the process force parameters were also determined. The results of numerical calculations were experimentally verified in laboratory conditions. The obtained results confirmed the possibility of semi-finished products of balls type manufacturing by means of rolling in multiple helical impressions.