Zulkhair Mansurov

Nanocrystalline Hydroxyapatite/Si Coating by Mechanical Alloying Technique

A novel approach for depositing hydroxyapatite (HA) films on titanium substrates by using mechanical alloying (MA) technique has been developed. However, it was shown that one-hour heat treatment at 800°C of such mechanically coated HA layer leads to partial transformation of desired HA phase to beta-tri-calcium phosphate (β-TCP) phase. It appears that the grain boundary and interface defects formed during MA promote this transformation. It was discovered that doping HA by silicon results in hindering this phase transformation process. The Si-doped HA does not show phase transition to β-TCP or decomposition after heat treatment even at 900°C.

Combustion Synthesis of Nanomaterials

An experimental study has been conducted in premixed and counterflow diffusion flames in order to obtain the nanocarbon materials. The original results in the field of synthesis of fullerenes, carbon nanotubes, syperhydrophobic soot,grapheme and nickel oxide nanoparticles in hydrocarbon flames were carried out for the last years at the Institute of Combustion Problems. Nanoparticles of nickel oxides contribute to the efficient absorption of light energy. Surfacing on the surface of a silicon solar cell of led to an increase in solar cell efficiency by 3%.

Producing nanomaterials in combustion

This paper presents original results in the area of synthesis of fullerenes, carbon nanotubes, and superhydrophobic soot in hydrocarbon flames and data on the self-propagating hightemperature synthesis of nanomaterials obtained in recent years at the Institute of Combustion Problems.

Synthesis of graphene films in a flame

The results of studying the synthesis of graphenes in a premixed propane-oxygen-argon flame at atmospheric conditions are reported. The temperature of 900–950°C and exposure time of 5 min are demonstrated to be suitable for the synthesis of graphene films on a nickel substrate, which is preferable to a copper substrate. It is demonstrated that the formation of graphene layers on the substrate occurs vertically along the flame height, with subsequent changeover to a soot structure. It is shown that the minimum number of graphene layers (two or three) is observed at angles of inclination of the substrate relative to the vertical axis of the flame within 0°–30°.

Synthesis and Structure Determination of Carbonized Nano Mesoporous Materials Based on Vegetable Raw Materials

This article presents the results of the synthesis of carbon nanomaterials: Nanoscale materials obtained by carbonization of waste agricultural products (apricot kernel, walnut, rice husk). The results of physico-chemical characteristics of the obtained nanomaterials.

High temperature transformation of tar-asphaltene components of oil sand bitumen

Transformations of high-molecular-weight compounds of oil sand natural bitumen under the heat treatment are studied. For that purpose natural bitumen isolated from oil sand taken from the Beke field (Kazakhstan) was used as a substrate. Thermal processing of natural bitumen leads to a general change in the chemical composition of components and an increase in the output of certain factions. The contents of oil, tar and asphaltenes were determined and the elemental composition of tar-asphaltene compounds was evaluated. Molecular structures of the tar and asphaltene components of natural bitumen before and after cracking have been defined from the data of elemental analysis, NMR spectroscopy and molecular weight. The high molecular compounds were presented as giant molecules containing small aromatic islands with some linked by aliphatic chains, which proved by infrared spectroscopy.

Aerogels Based on Microwave Plasma Torch Synthesized Graphene

In this research aerogels were synthesized by homogenization of carbon nanotubes and chitosan under ultrasonic treatment and active magnetic stirring, followed by freeze-drying in order to remove the liquid from its structure. Freeze-drying is characterized by a certain ratio of pressure and temperature at which the solid phase, in our case - the ice, turns into a gas without passing through a liquid phase. Freeze-drying was carried out at a temperature of-5 ° C and a pressure of 30-80 Pa. After freeze-drying which lasted for 20 hours, the as-obtained aerogels were carbonized at temperature of 800 °C in an inert atmosphere. Surface morphology of resulting aerogels was studied using scanning electron microscopy. The hydrophobicity and sorption capacity of these aerogels to organic liquids characterized by different densities were investigated. In addition, composite aerogels with the presence of graphene layers in the structure were obtained and the influence of introduction of graphene on aerogel’s properties was analyzed. It was found that composite aerogels based on graphene and carbon nanotubes with chitosan as a glue matrix are characterized by a better-developed porosity of surface with a smaller pore sizes, and their sorption capacity for organic liquids is also higher compared with the aerogels based on carbon nanotubes.

Flame synthesis of graphene layers at low pressure

The synthesis of graphene layers on a nickel substrate in a butane–benzene–oxygen premixed flame at a pressure of 40–100 Torr is studied. It is demonstrated that, the temperature of 900–950°C and exposure time of 0.5 min are sufficient for synthesizing graphene layers on a nickel substrate. It is shown that, at a pressure of 45–55 Torr, single-layer graphene is predominantly formed. It is found that, at a pressure of 90 Torr and an exposure time of 0.5 min, monolayer graphite can be produced, but with a lower yield as compared to that prepared at 45–55 Torr. It is demonstrated that the degree of defectiveness of graphenes decreases with the exposure time, reaching a minimum value of ID/IG = 0.36.

Scanning Electron Microscopic Studies of Carbonized Rice Husk and Apricot Stone

The microstructures of carbonized rice husk (CRH) and apricot stone (CAS) were studied to understand its adsorption of crude petroleum from water. Carbonize temperature affects the pore development of CRH, resulting in elongated large pores, as evident from the SEM data. The sorption capacities of CRH and CAS were compared in relation to different petroleum products. It was evaluated their possible practical use for water clean up from petroleum spills.

SHS-Composition Ceramics Obtained with Participation of Modified Wollastonite

The efficiency of using in the charge of SHS-mixtures wollastonite “active” additives of micron size activated and modified by different organic compounds as a result of mechanochemical treatment(MCT) is considered. The structure, composition and morphology of modified particles of wollastonite depending on the conditions of MCT in mills-activators of dynamic action are studied. During SHS of composition metal-oxide materials, wollastonite particles play the role of the centre of the mixture combustion site, provide the local increase of temperature, change thermodynamic characteristics of the sample synthesis process as a whole and contribute to formation of nanostructurized SHS-ceramics with high strength and dielectric characteristics.