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1.
Chemosphere ; 362: 142702, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38936486

RESUMO

This study presents a comprehensive investigation into NiXCo1-xFe2O4 (x = 0.5) spinel nanoparticles synthesized through a one-pot hydrothermal method using Co(NO3)2.6H2O and Ni(NO3)2.6H2O salts. XRD, FTIR, FESEM, and VSM analyses confirmed a cubic structure of NiXCo1-xFe2O4 (x = 0.5) nanoparticles without impurities. These nanoparticles exhibit efficient Zn (II) adsorption characteristics, following Langmuir isotherm and pseudo-second-order kinetics. The maximum adsorption capacity was measured to be 666.67 mg g-1 at pH = 7, with mechanisms involving both electrostatic attraction and cation exchange. Desorption studies indicate more than 75% Zn (II) recovery in an acidic environment (pH = 2) after three cycles. Computational analysis was used to validate the experimental results through Molecular Dynamics simulations, initially focusing on NiXCo1-xFe2O4 (x = 0.5). Further exploration involved variations in x at 0.25 and 0.75 to identify the optimal Ni and Co ratio in this bivalent cation spinel ferrite. Computational analyses reveal the superior performance of NiXCo1-xFe2O4 (x = 0.75) in Zn (II) removal, supported by radial distribution analysis, VdW energy, Coulombic energy, mean square displacement (MSD), root mean square displacement (RMSD), and interaction energy. This comprehensive study provides valuable insights into the adsorption behavior and structural stability of NiXCo1-xFe2O4 nanoparticles, showcasing potential applications in Zn (II) removal.


Assuntos
Cobalto , Compostos Férricos , Níquel , Zinco , Adsorção , Compostos Férricos/química , Cobalto/química , Zinco/química , Níquel/química , Cinética , Poluentes Químicos da Água/química , Óxido de Alumínio/química , Simulação de Dinâmica Molecular , Nanopartículas/química , Concentração de Íons de Hidrogênio , Óxido de Magnésio
2.
Chemosphere ; 349: 140966, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38109972

RESUMO

Today, with the advancement of science in nanotechnology, it is possible to remove dust nanostructures from the air breathed by humans or other fluids. In the present study, the separation of SiO2 molecules from H2O vapor is studied using molecular dynamics (MD) simulation. This research studied the effect of initial temperature, nanopore geometry, and initial pressure on the separation of SiO2 molecules. The obtained results show that by increasing the temperature to 500 K, the maximum velocity (Max-Vel) of the samples reached 2.47 Å/fs. Regarding the increasing velocity of particles, more particles pass via the nanopores. Moreover, the shape of the nanopore could affect the number of passing particles. The results show that in the samples with a cylindrical nanopore, 20 and 40% of SiO2 molecules, and with the sphere cavity, about 32 and 38% of SiO2 particles passed in the simulated structure. So, it can be concluded that the performance of carbon nanosheets with a cylindrical pore and 450 K was more optimal. Also, the results show that an increase in initial pressure leads to a decrease in the passage of SiO2 particles. The results reveal that about 14 and 54% of Silica particles passed via the carbon membrane with increasing pressure. Therefore, for use in industry, in terms of separating dust particles, in addition to applying an EF, temperature, nanopore geometry, and initial pressure should be controlled.


Assuntos
Nanoporos , Humanos , Simulação de Dinâmica Molecular , Vapor , Dióxido de Silício , Carbono , Temperatura , Poeira
3.
Sci Rep ; 12(1): 7522, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525873

RESUMO

Bioceramics have been commonly implemented to replace and restore hard tissues such as teeth and bones in recent years. Among different bioceramics, Baghdadite (BAG) has high bioactivity due to its ability to form apatite and stimulate cell proliferation. So, this structure is used widely for medical applications to treat bone-based diseases. Physically, we expect changes in temperature and pressure to affect the Baghdadite-based nanostructure's mechanical behaviour. So, in this computational study, we report the pressure/temperature effect on Baghdadite matrix with nanoscale size by using Molecular Dynamics (MD) approach. To this end, physical values like the total energy, temperature, final strength (FS), stress-strain curve, potential energy, and Young's modulus (YM) are reported. Simulation results indicated the mechanical properties of Baghdadite (BAG) nanostructure weakened by temperature and pressure increase. Numerically, the FS and YM of the defined structure reach 131.40 MPa/159.43 MPa, and 115.15 MPa/139.72 MPa with temperature/pressure increasing. Therefore, the increase in initial pressure and temperature leads to a decrease in the mechanical properties of nanostructures. These results indicate the importance of the initial condition in the Baghdadite-based nanostructures' mechanical behaviour that must be considered in clinical applications.


Assuntos
Simulação de Dinâmica Molecular , Nanoestruturas , Cerâmica/química , Nanoestruturas/química , Silicatos , Temperatura
4.
J Mol Model ; 28(1): 19, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34962594

RESUMO

Complex physical and chemical interactions take place in drug delivery using nanotube structures. Various descriptions of the ultrastructural arrangement to various nanotube design features ranging from geometries to surface modifications on the nano levels have been put forward. In this work, molecular dynamics simulations were applied to understand the boron nitride nanotube (BNNT) performance for drug delivery applications. Here, we have carried out the molecular dynamic (MD) simulation using the Tersoff force field to obtaining optimum performance of BNNT and fullerene molecules for the first time. The result of the equilibrated system accomplished excellent stability of BNNT during MD simulation, which proves the appropriateness of chosen force field. Furthermore, to describe the BNNT nano pumping process, we have calculated the fullerene molecule's velocity and translational/rotational kinetic energy. Numerically, by increasing simulated structures' temperature from 275 to 350 K, the nano pumping time varies from 9.31 to 8.55 ps. Moreover, the outcoming results indicate that atomic wave production in BNNT is an essential parameter for the nano pumping process. Therefore, with the help of the simulation result, we succeed in decreasing the nano pumping time to 7.79 ps by adjusting the nano pumping process parameters. Our study revealed the molecular-level dispersion mechanism of BNNT as a drug delivery tool. Concerning the medical applications of fullerenes as drug molecules, including antiviral activity, antioxidant activity, and drug delivery use, the current study can shed light on the understanding of the dispersion of nanotubes to optimize the process for several biomedical applications.


Assuntos
Compostos de Boro/química , Modelos Moleculares , Nanotubos/química , Algoritmos , Fenômenos Químicos , Modelos Químicos , Relação Estrutura-Atividade
5.
Sci Rep ; 11(1): 20265, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642408

RESUMO

In the present study, the improvement of mechanical properties of conventional concretes using carbon nanoparticles is investigated. More precisely, carbon nanotubes are added to a pristine concrete matrix, and the mechanical properties of the resulting structure are investigated using the molecular dynamics (MD) method. Some parameters such as the mechanical behavior of the concrete matrix structure, the validation of the computational method, and the mechanical behavior of the concrete matrix structure with carbon nanotube are also examined. Also, physical quantities such as a stress-strain diagram, Poisson's coefficient, Young's modulus, and final strength are calculated and reported for atomic samples under external tension. From a numerical point of view, the quantities of Young's modulus and final strength are converged to 35 GPa and 35.38 MPa after the completion of computer simulations. This indicates the appropriate effect of carbon nanotubes in improving the mechanical behavior of concrete and the efficiency of molecular dynamics method in expressing the mechanical behavior of atomic structures such as concrete, carbon nanotubes and composite structures derived from raw materials is expressed that can be considered in industrial and construction cases.

6.
J Therm Anal Calorim ; 143(3): 2841-2850, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33250660

RESUMO

COVID-19 is an epidemic virus arising from a freshly discovered coronavirus. Most people involved with the coronavirus will experience slight to moderate respiratory disease and recover without needing particular therapy. In this work, the atomic stability of the coronavirus at different thermodynamic properties such as temperature and pressure, was studied. For this purpose, the manner of this virus by atomic precession was described with a molecular dynamics approach. For the atomic stability of coronavirus description, physical properties such as temperature, total energy, volume variation, and atomic force of this structure were reported. In molecular dynamics approach, coronavirus is precisely simulated via S, O, N, and C atoms and performed Dreiding force field to describe these atoms interaction in the virus. Simulation results show that coronavirus stability has reciprocal relation with atomic temperature and pressure. Numerically, after 2.5 ns simulation, the potential energy varies from - 31,163 to - 26,041 eV by temperature changes from 300 to 400 K. Furthermore, this physical parameter decreases to - 28,045 eV rate at 300 K and 2 bar pressure. The volume of coronavirus is another crucial parameter to the stability description of this structure. The simulation shows that coronavirus volume 92% and 14% increases by 100 K and 2 bar variation of simulation temperature and pressure, respectively.

7.
Comput Part Mech ; 8(4): 737-749, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33224712

RESUMO

Coronavirus causes some illnesses to include cold, COVID-19, MERS, and SARS. This virus can be transmitted through contact with different atomic matrix between humans. So, this atomic is essential in medical cases. In this work, we describe the atomic manner of this virus in contact with various metallic matrix such as Fe, Al, and steel with equilibrium molecular dynamic method. For this purpose, we reported physical properties such as temperature, total energy, distance and angle of structures, mutual energy, and volume variation of coronavirus. In this approach, coronavirus is precisely simulated by O, C, S, and N atoms and they are implemented dreiding force field. Our simulation shows that virus interaction with steel matrix causes the maximum removing of the virus from the surfaces. After 1 ns, the atomic distance between these two structures increases from 45 to 75 Å. Furthermore, the volume of coronavirus 14.62% increases after interaction with steel matrix. This atomic manner shows that coronavirus removes and destroyed with steel surface, and this metallic structure can be a promising material for use in medical applications.

8.
Comput Methods Programs Biomed ; 188: 105256, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31841788

RESUMO

BACKGROUND AND OBJECTIVE: Human serum albumin (HSA) controls the flow of numerous chemical structures and molecules in the cardiovascular system. So, thermal conductivity of this atomic compound is important in medicinal applications. METHODS: In this work, the thermal conductivity of HSA is calculated with equilibrium/non-equilibrium molecular dynamic approaches. In these methods each HSA molecule is exactly represented by C, N, O and S atoms and their implemented dreiding potential. Finally by using Green-Kubo and Fourier's law the thermal conductivity of HSA/H2O mixture is calculated. RESULTS: Our calculated rates for thermal conductivity via equilibrium/non-equilibrium molecular dynamics methods are 0.496 W/m K and 0.448 W/m K, respectively. The calculated thermal conductivity for this structure was very close to the thermal conductivity calculated for water molecules which were reported by other research groups. Furthermore our simulated structures show that thermal conductivity of HAS/H2O mixtures has inverse relation with HAS molecules numbers and temperature of simulated atomic structures. CONCLUSIONS: Comparing thermal conductivity from equilibrium/non-equilibrium molecular dynamics methods for HAS/H2O shows that EMD and NEMD results are reliable and EMD calculated results are higher than NEMD results.


Assuntos
Simulação de Dinâmica Molecular , Albumina Sérica Humana/química , Condutividade Térmica , Carbono , Simulação por Computador , Análise de Fourier , Temperatura Alta , Humanos , Conformação Molecular , Nitrogênio , Oxigênio , Enxofre , Água
9.
Comput Methods Programs Biomed ; 185: 105169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31715331

RESUMO

BACKGROUND AND OBJECTIVE: Thermal conductivity of Deoxyribonucleic acid molecules is important for nanotechnology applications. Theoretical simulations based on simple models predict thermal conductivity for these molecular structures. METHODS: In this work, we calculate the thermal properties of Deoxyribonucleic acid with precise atomic arrangement via equilibrium and non-equilibrium molecular dynamics approaches. In these methods, each Deoxyribonucleic acid molecule is represented by C, N, O, and P atoms and implemented dreidng potential to describe their atomic interactions. RESULTS: Our calculated rate for thermal conductivity via equilibrium and non-equilibrium molecular dynamics methods is 0.381 W/m K and 0.373 W/m K, respectively. By comparing results from these two methods, it was found that the results from equilibrium and non-equilibrium molecular dynamics methods are identical, approximately. On the other hand, the number of DNA molecules and the equilibrium temperature of the simulated structures were important factors in their thermal conductivity rates, and their thermal conductivity was calculated at 0.323 W/m K-0.381 W/m K intervals for equilibrium and 0.303 W/m K-0.373 W/m K interval for non-equilibrium calculations. CONCLUSIONS: These results are in good agreement with thermal conductivity calculation with other research groups.


Assuntos
DNA/fisiologia , Simulação de Dinâmica Molecular , Condutividade Térmica , Algoritmos
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