T. A. Tripol’skaya

Effects caused by glutamic acid and hydrogen peroxide on the morphology of hydroxyapatite, calcium hydrogen phosphate, and calcium pyrophosphate

Reacting hydroxyapatite with H2O2 vapor at 10°C and brushite CaHPO4 · 2H2O with 90% H2O2 solution at 0°C (the hydroxyapatite and brushite were both prepared in the presence of glutamic acid) yielded the relevant peroxo solvates containing up to 18% hydrogen peroxide. The peroxo compounds and their degradation products obtained at 170–960°C were morphologically studied (using SEM). The factors influencing particle sizes are considered.

XPS characterization of sodium percarbonate granulated with sodium silicate

Granular sodium percarbonate has been characterized by X-ray powder diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The O1s binding energy for the solvating hydrogen peroxide molecules is 535.8 eV. Sodium percarbonate is stabilized by sodium silicate and polyphosphate.

Examination of the disinfecting properties of calcium peroxide and its suitability for improving hydrodynamic characteristics of surface water bodies

The fundamental possibility of using solid peroxides of alkaline-earth metals for water disinfection purposes was explored. The maximum peroxide concentration in solution is achieved with addition of a mixture of boric and phosphoric acids. Water treatment with calcium peroxide leads to stable dissolved oxygen levels and improves some hydrochemical characteristics of surface water bodies.

Cyclic peroxosolvated calcium polyphosphates

Hydrogen peroxosolvated compounds containing up to 16% H2O2 have been synthesized by reacting the calcium cyclopolyphosphates NaCaP3O9 · 2H2O, Ca2P4O12 · 4H2O, and Ca3P6O18 · 9H2O with hydrogen peroxide vapor or with a 70–96% hydrogen peroxide solution. In these reactions, hydrogen peroxide serves both as a source of solvating H2O2 and a dehydrating agent. Nanosized peroxosolvated calcium polyphosphates have been obtained using an organic template (gelatin). The compounds have been characterized by scanning electron microscopy, IR spectroscopy, X-ray diffraction, and thermal analysis.

Nanostructured sodium calcium tripolyphosphate and its peroxo derivatives are a new generation of bioceramic materials

Nanostructured sodium calcium tripolyphosphate and its peroxosolvates were synthesized and studied by IR spectroscopy, electron microscopy, X-ray powder diffraction, and thermogravimetry. Their specific surface areas were measured. The high-porosity structure and antibacterial properties of these materials make them promising for use as bioceramics materials.

Potassium peroxostannate nanoparticles

Stable amorphous potassium peroxostannate nanoparticles with controlled sizes (10–100 nm), morphology, and hydrogen peroxide percentage (19–30 wt %) were synthesized for the first time. The compounds were characterized by vibrational spectroscopy, 119Sn MAS NMR spectroscopy, powder X-ray diffraction, and thermogravimetry. These characteristics were compared to those for K2Sn(OH)6 and K2Sn(OOH)6. Potassium peroxostannate particles are mainly built of peroxo-bridged polymer chains. The particles are stable when stored in a dry state or suspended in nonaqueous solvents; in contact with water, they release hydrogen peroxide.

Synthesis and crystal structure of new alkali metal hydrogen tellurates

New alkali metal hydrogen tellurates have been synthesized, and their structures have been determined by X-ray crystallography. Hydrogen tellurates I–VI contain centrosymmetric binuclear anions [Te2O10H4+x](4−x)−, where x=0, 1, 2. Hydrogen tellurates II and VI contain, in addition to the binuclear anion, mononuclear species [TeO6H4]2− and Te(OH)6, respectively. The CNs of alkali metals vary from 8 to 12. In all structures, the hydrogen atoms (of both the hydroxy groups and water molecules) are involved in hydrogen bonding.

A composite based on sodium germanate and reduced graphene oxide: Synthesis from peroxogermanate and application as anode material for lithium ion batteries

A composite based on sodium germanate and reduced graphene oxide was obtained for the first time by precipitating the initial peroxogermanate on a graphene oxide followed by heat treatment in vacuum. According to powder X-ray diffraction, sodium germanate crystallizes during the heat treatment in vacuum at 500°C. Scanning transmission electron microscopy examination showed that sodium peroxogermanate nanoparticles form a thin film on the surface of graphene oxide flakes. The electrochemical characteristics of composites obtained with different heat treatment conditions were studied as the anodes of lithium ion batteries.

Study of tin dioxide–sodium stannate composite obtained by decomposition of peroxostannate as a potential anode material for lithium-ion batteries

A tin dioxide–sodium stannate composite has been obtained by the thermal treatment of sodium peroxostannate nanoparticles at 500°C in air. X-ray powder diffraction study has revealed that the composite includes crystalline phases of cassiterite SnO2, sodium stannate Na2Sn2O5, and sodium hexahydroxostannate Na2Sn(OH)6. Scanning electron microscopy has shown that material morphology does not change considerably as compared with the initial tin peroxo compound. Electrochemical characteristics have been compared for the anodes of lithium-ion batteries based on tin dioxide–sodium stannate composite and anodes based on a material manufactured by the thermal treatment of graphene oxide–tin dioxide–sodium stannate composite at 500°C in air.

Synthesis of nanostructured sodium calcium tripolyphosphate using organic templates

We have developed a process for the synthesis of nanostructured sodium calcium tripolyphosphate with the use of organic templates, including amino acids (glycine and L-aspartic, L-glutamic, and ɛ-aminocaproic acids), polysaccharides (sodium and calcium alginates and maltodextrin), and Trilon B. The synthesized sodium calcium tripolyphosphate nanopowders have been characterized by scanning electron microscopy, X-ray diffraction, and IR spectroscopy. The particle size of the nanopowders is shown to be determined by the properties of the template and ranges from ∼20 nm to ∼20 μm. We have studied the biological activity of peroxo derivatives of sodium calcium tripolyphosphate for Escherichia coli.