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Papers by Jargalan Narmandakh

Solid State Phenomena, 2018

In recent time, interest to ferrite magnetic nanomaterials has considerably grown mainly due to t... more In recent time, interest to ferrite magnetic nanomaterials has considerably grown mainly due to their much promising medical and biological applications. The spinel ferrite powder samples having high heat generation ability in AC magnetic field was studied for application to hyperthermia treatment of cancer tumor. These properties of ferrites are strongly depending on their chemical composition, ion distribution, spin orientation and method of preparation in general and crystal structure in particular nature of the material. In this study, several samples of ferrite magnetic structures were investigated by neutron diffraction. The explanation of the mechanism to occurs the heat generation ability in the magnetic materials and the electronic and magnetic states of ferrite-spinel – type structures were theoretically defined by the first-principles calculations within the framework of DFT.

Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques, 2015

The dissolution kinetics of fullerene C 60 in solvents with different polarities, including tolue... more The dissolution kinetics of fullerene C 60 in solvents with different polarities, including toluene, benzene, and N methylpyrrolidone (NMP), at varying concentrations and temperatures of the solution, and conditions of preparation, is studied by UV Vis spectroscopy. For a polar C 60 /NMP solution, stable peaks in the absorption spectrum were not found; the evolution of the spectra is determined by the kinetics of the for mation of charge transfer complexes in the solution. It is shown that the dissolution of fullerene in low polar toluene and benzene is described by the Noyes-Whitney equation; the fullerene concentration in a solution is determined by the absorption peak at λ = 408 nm. The parameters in the dissolution equations for different conditions are determined.

Physics of the Solid State, 2014

ABSTRACT The aggregate growth in a C60/N-methylpyrrolidone (NMP) solution has been considered in ... more ABSTRACT The aggregate growth in a C60/N-methylpyrrolidone (NMP) solution has been considered in the framework of the approach developed earlier for describing the cluster growth kinetics in fullerene polar solutions. The final cluster size distribution functions in model solutions have been estimated for two fullerene aggregation models including the influence of complex formation on the cluster growth using extrapolations of the characteristics of the cluster state and distribution parameters. Based on the obtained results, the model curves of small-angle neutron scattering have been calculated for a C60/NMP solution at various values of the model parameters.

Solid State Phenomena, 2021

Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficienc... more Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficiency as heating elements. The biocompatibility of Mg 0.8 Ni 0.2 Fe 2 O 4 nanoparticles was studied using a cytotoxicity colony formation assay and a cell viability assay. HeLa cells exhibited cytotoxic effects when exposed to three different concentrations of 150 μg /ml, 100 μg /ml, and 50 μg /ml nanoparticles. Therefor e, c oncentrations of 50 μg /ml showed the lowest cytotoxic activity and the lowest toxicity to living cells. In vitro cytotoxicity of samples was then investigated by two methods, colony formation assay and cell viability assay. The Hela inhibited cell growth as 16.8% during heating by magnetic field generators.

physica status solidi (b), 2011

ABSTRACT Model growth of fullerene C60 clusters in the solution in N-methyl-2-pyrrolidone (NMP) i... more ABSTRACT Model growth of fullerene C60 clusters in the solution in N-methyl-2-pyrrolidone (NMP) is considered in the frame of nucleation theory. In addition to the previous models, the reason for the supersaturation caused the cluster formation is related to the appearance of new C60–NMP complexes with NMP. The dissolution process is taken into account. Different regimes of the proposed models depending on the kinetic parameters are distinguished and analyzed.

Journal of Molecular Liquids, 2012

ABSTRACT Theoretical models for describing the kinetics of fullerene cluster growth in C60 soluti... more ABSTRACT Theoretical models for describing the kinetics of fullerene cluster growth in C60 solutions in N-methyl-2-pyrrolidone (NMP) are presented. First, a detailed review of current state of experimental investigation of C60/NMP is given. The relation between C60–NMP complex formation, cluster growth and their impact on solvatochromism is discussed.Next, a theoretical approach for description of cluster growth, based on kinetic equations of segregation, is proposed. Two modifications of basic approach are given. First one treats cluster growth in a supersaturated solution of C60, where new complex formation eventually limits growth of aggregates. In the second model a two-step process of cluster growth is considered: complex formation and cluster growth. The solution of C60–NMP complexes is supersaturated, while initial, “free” C60 does not aggregate. For each model a procedure for obtaining parameters is proposed and the parameter values are estimated.

Solid State Phenomena, 2018

In recent time, interest to ferrite magnetic nanomaterials has considerably grown mainly due to t... more In recent time, interest to ferrite magnetic nanomaterials has considerably grown mainly due to their much promising medical and biological applications. The spinel ferrite powder samples having high heat generation ability in AC magnetic field was studied for application to hyperthermia treatment of cancer tumor. These properties of ferrites are strongly depending on their chemical composition, ion distribution, spin orientation and method of preparation in general and crystal structure in particular nature of the material. In this study, several samples of ferrite magnetic structures were investigated by neutron diffraction. The explanation of the mechanism to occurs the heat generation ability in the magnetic materials and the electronic and magnetic states of ferrite-spinel – type structures were theoretically defined by the first-principles calculations within the framework of DFT.

Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques, 2015

The dissolution kinetics of fullerene C 60 in solvents with different polarities, including tolue... more The dissolution kinetics of fullerene C 60 in solvents with different polarities, including toluene, benzene, and N methylpyrrolidone (NMP), at varying concentrations and temperatures of the solution, and conditions of preparation, is studied by UV Vis spectroscopy. For a polar C 60 /NMP solution, stable peaks in the absorption spectrum were not found; the evolution of the spectra is determined by the kinetics of the for mation of charge transfer complexes in the solution. It is shown that the dissolution of fullerene in low polar toluene and benzene is described by the Noyes-Whitney equation; the fullerene concentration in a solution is determined by the absorption peak at λ = 408 nm. The parameters in the dissolution equations for different conditions are determined.

Physics of the Solid State, 2014

ABSTRACT The aggregate growth in a C60/N-methylpyrrolidone (NMP) solution has been considered in ... more ABSTRACT The aggregate growth in a C60/N-methylpyrrolidone (NMP) solution has been considered in the framework of the approach developed earlier for describing the cluster growth kinetics in fullerene polar solutions. The final cluster size distribution functions in model solutions have been estimated for two fullerene aggregation models including the influence of complex formation on the cluster growth using extrapolations of the characteristics of the cluster state and distribution parameters. Based on the obtained results, the model curves of small-angle neutron scattering have been calculated for a C60/NMP solution at various values of the model parameters.

Solid State Phenomena, 2021

Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficienc... more Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficiency as heating elements. The biocompatibility of Mg 0.8 Ni 0.2 Fe 2 O 4 nanoparticles was studied using a cytotoxicity colony formation assay and a cell viability assay. HeLa cells exhibited cytotoxic effects when exposed to three different concentrations of 150 μg /ml, 100 μg /ml, and 50 μg /ml nanoparticles. Therefor e, c oncentrations of 50 μg /ml showed the lowest cytotoxic activity and the lowest toxicity to living cells. In vitro cytotoxicity of samples was then investigated by two methods, colony formation assay and cell viability assay. The Hela inhibited cell growth as 16.8% during heating by magnetic field generators.

physica status solidi (b), 2011

ABSTRACT Model growth of fullerene C60 clusters in the solution in N-methyl-2-pyrrolidone (NMP) i... more ABSTRACT Model growth of fullerene C60 clusters in the solution in N-methyl-2-pyrrolidone (NMP) is considered in the frame of nucleation theory. In addition to the previous models, the reason for the supersaturation caused the cluster formation is related to the appearance of new C60–NMP complexes with NMP. The dissolution process is taken into account. Different regimes of the proposed models depending on the kinetic parameters are distinguished and analyzed.

Journal of Molecular Liquids, 2012

ABSTRACT Theoretical models for describing the kinetics of fullerene cluster growth in C60 soluti... more ABSTRACT Theoretical models for describing the kinetics of fullerene cluster growth in C60 solutions in N-methyl-2-pyrrolidone (NMP) are presented. First, a detailed review of current state of experimental investigation of C60/NMP is given. The relation between C60–NMP complex formation, cluster growth and their impact on solvatochromism is discussed.Next, a theoretical approach for description of cluster growth, based on kinetic equations of segregation, is proposed. Two modifications of basic approach are given. First one treats cluster growth in a supersaturated solution of C60, where new complex formation eventually limits growth of aggregates. In the second model a two-step process of cluster growth is considered: complex formation and cluster growth. The solution of C60–NMP complexes is supersaturated, while initial, “free” C60 does not aggregate. For each model a procedure for obtaining parameters is proposed and the parameter values are estimated.