فصلنامه نانو مقیاس
سال هفتم شماره 3 (پیاپی 27، پاییز 1399)

: In this paper, cobalt ferrite nanoparticles CoFe2O4 and starch-capsaicin anticancer drug nanocomposites were synthesized. Structure morphology was investigated by scanning electron microscopy, crystalline phase X-ray diffraction and core-shell encapsulation were also investigated using TEM. In addition, capsaicin release was performed in human stomach-like environment at physiological temperature of human body and was subjected to ultraviolet visible spectroscopy. The results represent the introduction of a new and effective nanostructure for cancer treatment. Preparation and Characterization of Cobalt Ferrite – Starch Nanocomposite as a Nanocarrier for Gradual Release of the Capecitabine Anticancer Drug

Manganese chiral single ring nanostructure are produced using oblique angle deposition together with rotation of substrate holder about its surface normal. The structural characterization of the produced samples was obtained using field emission scanning electron microscope (FESEM) and atomic force microscope (AFM). The optical spectra of the samples were obtained using a single beam spectrophotometer for the incident light of the surface normal. Then, absorption spectra are obtained for linearly polarized different azimuthal angles by homogenization method. Obtained results are consistent with the experimental optical absorption spectra. The plasmonic oscillations type inside nanostructure of chiral single ring is investigated by using the discrete dipole approximation (DDA).

Magnetic nanoparticles of CoFe2O4 were synthesized through a solid-state procedure in agate mortar and then calcined at high temperatures. The obtained CoFe2O4 nanoferrite was characterized by XRD, SEM, FT-IR and VSM techniques and used as catalyst in the one-pot efficient conversion of different epoxides bearing aryl, allyl and alkyl substituents to the corresponding 1,2-diacetoxy esters with acetic anhydride in oil bath 70 ºC under solvent-free conditions. Synthesis of 1,2-dicetates was carried out within 1-4 h with 77-95 yields. The magnetic nanocatalyst was easily separated using an external magnet and reused several times without any significant loss of catalytic activity or magnetic property.

In this paper two resonant photonic crystals is proposed that their optical response depends not only to the modulation of the dielectric function but also to the interaction of the incident light with the crystal's internal excitations. Alternating layers made of GaAs (as the barrier layer) and InAs/InGaAs quantum dots (dipole active layer) are selected as the main building blocks of the crystals. Structural order is disturbed by adding defects. Transfer Matrix Method (TMM) is applied to evaluate the optical features of the crystals and in order to model the real situation, the roles of the effective exitonic susceptibility besides the homogenous and non-homogenous broadenings are considered in calculations. Dependence of the structures response (including width and wavelength range of the stop band and resonant modes) to the structural parameters such as layers period number, size of the slabs and homogeneity of the layers are studied at the first step. Extracting the optimum values, tunability of the optical features with external parameters such as crystal temperature and light incident angle is explored systematically. Results clearly show the great potential of the proposed crystals for applications such as all optical tunable filters, frequency dividers and switches.

Luminescent graphene oxide quantum dots have attracted tremendous attention from the scientists in chemistry, materials science, physics and biology, because of their superiority of good stability, excellent optical and electrochemical properties, resistance to photo-bleaching, and low cytotoxicity. In the research, Graphene oxide quantum dot were synthesized using a simple and direct method. In the following, to increase and change the luminescence, graphene oxide doped with nitrogen N and sulfur S in a single step in the presence of thiourea and ammonia were synthesized. the graphene oxide quantum dots were characterized by infrared, UV–Vis absorption, photoluminescence spectroscopy, and TEM microscopy. S and N doped graphene oxide quantum dots, unlike the base graphene oxide quantum dots, have a blue luminescence and higher intensity than their base counterpart. Because of this prominent luminescence feature, N and S doped graphene oxide quantum dots can be used for medical imaging and other optical applications.

In the present research, nanoparticles and silicon nanoparticles were synthesized using gold catalyst by chemical vapor deposition methods and liquid-solid vapor VLS techniques at different times. The Nano structural properties of the synthesized samples were investigated using experimental techniques of scanning electron microscopy SEM, transmission electron microscopy TEM and X-ray diffraction XRD. The results of SEM images showed nanoparticles with spherical morphology with diameters in the range of 60 to 180 nm and nanoparticles with needle morphology. XRD analysis confirmed the presence of crystalline phase silicon peaks in the synthesized sample. The results of TEM and Raman show the inner structure of the samples at 10 and 20 nm scales as crystalline core-shell, respectively.

In this paper, synthesis method of a polymer-based nano composite and use of brass nanoparticles are investigated. First, brass nanoparticles are produced by mechanical scratching and are characterized by AFM, DLS and XRD to investigate the size, distribution and phase of nano particles. Then, nanoparticles are added to ABS solved in chloroform to produce the mentioned nano composite. Next, the 4 probe point test is used to investigate the electrical conductivity of synthesized nano composite samples with different weight percentages of brass. Results show that electrical conductivity is increased by increasing of brass nano particle percentage, as electrical conductivity of the sample with 30 percent of brass reaches 1.8  105 S/m. Therefore, a polymer-based nano composite is synthesized which has many industrial applications.

CdTe and CdTe/CdSe QDs synthesized with microwave method.The synthesized QDs were characterized by means of XRD, PL, UV-Vis, FESEM, EDS and RAMAN analysis. XRD, EDS and RAMAN analysis confirmed successfully formation of core-shell structure. CdTe/CdSe core-shell structure is type II. CdTe QDs indicated a band gap emission with peak about 535nm. PL peak intensity increased significantlyand indicated a red shift after CdSe shell growth because of type II core-shell structure. In this method shell thickness simply control by time of microwave radiation that it makes photoluminescence range of QDs from green to red.

<![CDATA[In this study, the effect of zigzag Zinc sulfide layer on refractive index, extinction coefficient, transmittance percentage and its comparison with zero degree labeling of the same material is investigated. Thin layers of zinc sulfide are deposited on the glass substrate by the physical vapor deposition method. By examining the optical and structural properties of these samples, it was observed that with this method, the zigzag layer, optical transmittance, absorption coefficient and extinction coefficient were increased with to zero degree and its refractive index decreased and the crystal size also increased. This result illustrates the effect of the GLAD method on the optical and structural properties of the thin films.

A H2S gas sensor was fabricated by growing SnO2 nanorods on an interdigitated Ag substrate spin coating SnO2 nanoparticles. The geometry, morphology, chemical composition, optical and electrical properties were investigated by scanning electron microscopy, Energy Dispersive X-ray Spectroscopy (EDAX), X-Ray diffraction, photoluminescence spectroscopy and absorption spectroscopy. The obtained sensor was further improved by doping Ag on the SnO2 Nano-Particles and a unique method of simultaneous exposure to UV illumination and applying and electrical potential (self-heating). Our attempts lead to production of a highly sensitive sensor in the low detection range (500 ppb-10ppm) in which H2O gas interfering was also used for the first time in the gas sensing. Regarding this achievement, the sensor response and recovery times remarkably boosted in 10 ppm H2O gas from 10 and 11s in initial method to 5 and 8s in the improved method, respectively. The sensor cross-sensitivity toward C6H6, C2H5OH, CO2 and NH3 was also examined in order to determine the sensor selectivity.

In this article, the structural, magnetic, morphological and optical properties of Cobalt ferrite nanoparticles are investigated and compared with Cobalt ferrite thin film. Cobalt ferrite nanoparticles were prepared by auto-combustion Sol-gel method and Cobalt ferrite thin film was prepared by Sol-gel and Spin-coating methods. Structural properties of the samples were investigated using X-ray diffraction spectroscopy and followed by Rietveld and Williamson-Hall analysis. The magnetic properties of the samples, were investigated using the .vibrating sample magnetometer (VSM) and the Faraday magneto-optical effect tests. The morphology of the samples were performed by scanning electron microscopy (SEM), atomic force microscopy (AFM) and field emission electron microscopy (FESEM). Finally, the optical and band gap of the samples were calculated using UVVis diffuse reflectance spectroscopy.

In this study, the interaction of letrozole C17H11N5 and polymer poly 2-ethyl-2-oxazoline C31H58N6O7 was theoretically investigated. Effects of Electronic Asymmetry and Bipolar-Bipolar Interactions on Structural Properties and Letrozole Drug Responsiveness in the Presence of Polymer 2-Ethyl-2-Oxazoline Using DFT Density Functional Theory in Quantum Mechanics Computational theoretical levels of B3LYP and basic series 6-31G were studied in gas phase and water solution. Thermodynamic functional analysis indicate that the relative energies ΔE, free Gibbs energies ΔG and enthalpies ΔH are negative for system but the calculated entropies ΔS are Positive, suggesting thermodynamic favorability for covalent attachment of Letrozole on polymer and this results confirm the structural stability of the Letrozole -PEOZ in both gas and solvent phases. Delocalization of charge density between the bonding or lone pair and antibonding orbitals calculated by NBO analysis. These methods are used to determine structural characterization PEOZ during the adsorption reactions in the gas phase. In order to investigation of conductivity and electronic properties of PEOZ in the reaction with Letrozole, the total electronic energy, dipole moment, orbital energies, charge density, density of state DOS, LUMO-HOMO energy bond gaps, Adsorption energies EAd, the global index includes hardness η, electronegativity χ, electrophilicity index w, chemical softness S and electronic chemical potential μ were calculated. In the following, the results of IR drug, polymer and drug-polymer complex spectra were examined and the observed convergence between experimental and theoretical data indicates the accuracy of the calculations and the theoretical method can be cited as a valid method. 

In this research, Fe3O4@Propylsilane-Pyridine[HSO4] magnetic nanoparticles were synthesized via functionalization of Fe3O4 by tri-methoxy silyl propyl amine, pyridine-2-carbaldehyde and sulfuric acid. The structures of the synthesized nanoparticles at different stages were confirmed by FT-IR spectroscopy. Also, the crystal structure, morphology and thermal stability of the nanoparticles were investigated using XRD, SEM, TEM and TGA analyzes. Finally, dihydropyrido[3,2-d: 5,6-d'] dipyrimidine derivatives were synthesized by using of these nanoparticles as an effective catalysts. Comparison of the performance of this catalyst with other catalysts showed that the nano-catalysts made in this research, significantly increase the yield and reaction rate compared to other catalysts.

In this paper, synthesis of Copper Oxide nano rod particles from Copper Oxide microparticles obtained from Gold ore flotation concentrate in Copper Sulfate salt medium under specific temperature, pH and time conditions. Morphology and dispersion using Sodium Tartarate salt as the main reactant was done. The results were confirmed by XRF, XRD, SEM, EDX measurements. The EDX and SEM results show the synthesized and calcined (300-410 ºC, t=50-75 min) Copper nanorods in 1% sodium Tartrate medium, and finally formed particle rods with a size of 54 × 215 nm.