Average Diameter Of Nanoparticles Research Articles

Synthesis and characterization of magnesium oxide nanoparticles by atmospheric non-thermal plasma jet

The invention of the system which facilitates and assures the use of atmospheric-pressure plasma technology has been used in several fields, including medicine and nanotechnology. In our work, magnesium oxide (MgO) nanoparticles (NPs) were created using a high voltage power supply of 21 ​kV at high-frequency equipment that produced a 6 ​kHz output. MgO NPs were successfully created at various times. X-Ray Diffraction (XRD) analysis showed that MgO NPs have a polycrystalline and an average crystalline size of 9.365 and 14.253 ​nm in both preparation times (10 and 12 ​min). Additionally, field emission scanning electron (FE-SEM) images show the single nanoparticles appear flake-like, with a thickness of 10 ​nm at 500 ​nm magnification and a width of 20 ​nm. Transmission Electron Microscopy (TEM) was employed to analyze the homogeneous, compact, and dense surface of the produced MgO NPs. Transmission electron microscopy (TEM) analysis showed that the MgO nanoparticle's average diameter ranged from 6 to 18 ​nm. Atomic Force Microscopy (AFM) was also used to uncover the degree of cooperation between the surfaces of MgO NPs, and the results showed a high extraordinary topographic contrast of the MgO NPs with a surface roughness of 2.170 ​nm.

A Comparative Study of the Biodurability and Persistence of Gold, Silver and Titanium Dioxide Nanoparticles Using the Continuous Flow through System.

The potential for nanoparticles to cause harm to human health and the environment is correlated with their biodurability in the human body and persistence in the environment. Dissolution testing serves to predict biodurability and nanoparticle environmental persistence. In this study, dissolution testing using the continuous flow through system was used to investigate the biodurability and persistence of gold nanoparticles (AuNPs), silver nanoparticles (AgNPs) and titanium dioxide nanoparticles (TiO2 NPs) in five different simulated biological fluids and two synthetic environmental media to predict their behaviour in real life situations. This study examined the physicochemical properties and agglomeration state of gold, silver and titanium dioxide nanoparticles before and after dissolution tests using three different techniques (UV-vis, XRD and TEM). The UV-vis spectra revealed that all three nanoparticles shifted to higher wavelengths after being exposed to simulated fluids. The titanium powder was found to be mixed with both rutile and anatase, according to XRD examination. The average diameter of gold nanoparticles was 14 nm, silver nanoparticles were 10 nm and titanium dioxide nanoparticles were 25 nm, according to TEM images. The gold and silver nanoparticles were observed to be spherical, but the titanium dioxide nanoparticles were irregular in shape, with some being spherical. The level of dissolved nanoparticles in simulated acidic media was higher in magnitude compared to that dissolved in simulated alkaline media. The results obtained via the continuous flow through dissolution system also displayed very significant dissolution rates. For TiO2 NPs the calculated half-times were in the range of 13-14 days, followed by AuNPs ranging between 4-12 days, significantly longer if compared to the half-times of AgNPs ranging between 2-7 days. AuNPs and TiO2 NPs were characterized by low dissolution rates therefore are expected to be (bio)durable in physiological surroundings and persistent in the environment thus, they might impose long-term effects on humans and the environment. In contrast, AgNPs have high dissolution rates and not (bio)durable and hence may cause short-term effects. The results suggest a hierarchy of biodurability and persistence of TiO2 NPs > AuNPs > AgNPs. It is recommended that nanoparticle product developers should follow the test guidelines stipulated by the OECD to ensure product safety for use before it is taken to the market.

Synthesis of Chitosan-Silver Nanocomposite and Its Evaluation as an Antibacterial Coating for Mobile Phone Glass Protectors.

An easy and environment-friendly route for antibacterial coating suited for mobile phone glass protectors was successfully demonstrated. In this route, freshly prepared chitosan solution in 1% v/v acetic acid was added with 0.1 M silver nitrate solution and 0.1 M sodium hydroxide solution and incubated with agitation at 70 °C to form chitosan-silver nanoparticles (ChAgNPs). Varied concentrations of chitosan solution (i.e., 0.1, 0.2, 0.4, 0.6, and 0.8% w/v) were used to investigate its particle size, size distribution, and later on, its antibacterial activity. Transmission electron microscope (TEM) imaging revealed that the smallest average diameter of silver nanoparticles (AgNPs) was 13.04 nm from 0.8% w/v chitosan solution. Further characterizations of the optimal nanocomposite formulation using UV-vis spectroscopy and Fourier transfer infrared spectroscopy were also performed. Using a dynamic light scattering zetasizer, the average ζ-potential of the optimal ChAgNP formulation was at +56.07 mV, showing high aggregative stability and an average ChAgNP size of 182.37 nm. The ChAgNP nanocoating on glass protectors shows antibacterial activity against Escherichia coli (E. coli) at 24 and 48 h of contact. However, the antibacterial activity decreased from 49.80% (24 h) to 32.60% (48 h).

Effects of Coexisting Anions on the Formation of Hematite Nanoparticles in a Hydrothermal Process with Urea Hydrolysis and the Congo Red Dye Adsorption Properties

Crystalline hematite nanoparticles as adsorbents for anionic Congo red dye were prepared by a hydrothermal process using urea hydrolysis. To examine the effects of coexisting anions in a solution on the formation of hematite nanoparticles, different iron(III) salts, including iron chloride hexahydrate, iron nitrate nonahydrate, iron sulfate n-hydrate, ammonium iron sulfate dodecahydrate, and basic ferric acetate, were employed as iron-ion sources. After the hydrothermal treatment of the solution, consisting of an iron salt and urea at 423 K for 20 h, a single phase of hematite was formed from the iron-nitrate solution. The results suggested that the hydrothermal formation of hematite depended on the stability of iron complexes formed in the starting solution. The average crystallite size and median diameter of hematite nanoparticles also depended on the coexisting anions, suggesting that the appropriate selection of the coexisting anions in the starting solution can allow for control of the crystallite size and particle diameter of hematite nanoparticles. The Congo red adsorption kinetics and isotherms of the hematite nanoparticles were described by the Elovich model and Langmuir model, respectively. The adsorption thermodynamics parameters were estimated, which suggested an exothermic and spontaneous process. The results demonstrated good adsorption properties for Congo red adsorption.

Synthesis of Rumex hastatus-based silver nanoparticles induced the inhibition of human pathogenic bacterial strains

The development of antibiotic resistance in pathogenic bacterial strains has drawn attention to the quest for new natural antibacterial drugs. Therefore, in the present study, extracts of Rumex hastatus leaves were obtained in methanol and water, and R. hastatus-based silver nanoparticles (AgNPs) were synthesized. Structural and functional properties of synthesized silver nanoparticles were determined by UV–vis spectroscopy, XRD, FTIR and SEM. The synthesized AgNPs and crude extracts were tested to check their antibacterial potential against human pathogenic bacterial strains of Staphylococcus aureus, Staphylococcus haemoliticus, Bacillus cereus, Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa in well diffusion and broth dilution methods. The present investigation has revealed for the first time that the broth dilution method was found more reproducible than that of the well diffusion method even at lower concentrations of AgNPs and crude extracts. UV– Vis spectroscopic analysis of AgNPs revealed a peak at 367 nm. XRD pattern showed a face-centered cubical to the spherical structure of AgNP crystals. FTIR analysis revealed that flavonoids and terpenoids are responsible for the reduction of AgNO3 to Ag+. SEM analysis determined the spherical structure and 51 nm average diameter of nanoparticles. The antibacterial activity of R. hastatus-based (AgNPs) was found to be significantly higher than aqueous plant extract and silver nitrate alone. Bacterial growth was inhibited by R. hastatus-based AgNPs in a dose-dependent manner. To our knowledge, silver nanoparticles (AgNPs) of R. hastatus were synthesized and characterized for the first time in this study and, based on the findings of current research work R. hastatus extract-based silver nanoparticles are suggested to be used as an antibacterial drug instead of synthetic drugs for the treatment of various human diseases/infections caused by the tested bacterial strains.

Fe<sub>3</sub>O<sub>4</sub> Nanoparticles Prepared by Coprecipitations Method for Hyperthermia Therapy

Magnetic nanoparticles (Fe3O4) have considerable attention in various biomedical applications such as biosensors, drug delivery systems in the body, magnetic resonance imaging (MRI), and hyperthermia therapy. Hyperthermia therapy uses heat controlled by applied AC (Alternating Current) magnetic to kill cancer cells. This research aims to determine the effect of changes in temperature caused by the AC magnetic field on the varied magnetic nanoparticle solution. The Synthesize of Fe3O4 used the coprecipitation method to produce Fe3O4 nanoparticles. Mass of Fe3O4 nanoparticles varied of 95 mg and 125 mg. Nanoparticles physical properties were characterized using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and vibrating sample magnetometer (VSM). XRD profiles indicated that magnetic (Fe3O4) nanoparticles were successfully synthesized with a crystal size of 7.76 nm. SEM characterization of Fe3O4 nanoparticles was carried out at a magnification of 150.000 times and the average diameter of Fe3O4 powder nanoparticles was 20 nm. The temperature change measurement was performed using an AC magnetic field of 2.8 mT and frequency of 343 Hz, and time recorded changes temperature in 660 seconds. The temperature changes for solution concentrations of 95 mg and 125 mg were 7.7°C and 9.8°C, respectively. the concentration of solutions affects the value of the Specific Absorption Rate (SAR). The SAR values of each concentration of Fe3O4 solution were 0,0069 W/g and 0.0096 W/g. It proves that Fe3O3 prepared by coprecipitation method has potential for hyperthermia therapy application.

Quercetin nanocrystals prepared by a novel technique improve the dissolution rate and antifibrotic activity of quercetin.

Aim: To develop quercetin nanocrystals by a simple approach and to evaluate their in vivo antifibrotic efficacy. Materials & methods: Nanosuspensions were fabricated by a thin-film hydration technique and ultrasonication. The influence of process variables on the average diameter of quercetin nanoparticles was investigated. Moreover, in vivo efficacy was investigated in an established murine CCl4-induced fibrosis model. Results: Nanocrystals showeda particle size of <400nm. The optimized formulations showed an increase in dissolution rate and solubility. Quercetin nanocrystals markedly prevented fibrotic changes in the liver, as evidenced by mitigated histopathological changes and diminished aminotransferase levels and collagen accumulation. Conclusion: The findings reflect the promising potential of quercetin nanocrystals for liver fibrosis prevention.

Synthesis and Characterization of some metals (Sn, Ni, Zn and Co) doped with CdO Nanoparticles by Co-Precipitation method for super capacitor applications

In this present investigation, a set of pure and some metals doped Cadmium oxide nanoparticles were synthesized by the way of co-precipitation method. The precursor materials used in this current work were cadmium nitrate, tin (II) chloride, nickel acetate, zinc acetate dihydrate and cobalt (II) chloride has been make uses of a precursor materials. The as-synthesized nanopowders were characterized by XRD, FTIR, UV-Vis and SEM analysis. The X-Ray Diffraction patterns revealed a polycrystalline having the characteristic peaks are well matched with the phase purity of cubic structure. Scanning Electron Microscope exhibit surface morphology, Fourier Transform Infrared spectrum has affirmed the presence of the functional groups present in the pure and metals doped cadmium oxide nanoparticles. The room temperature photoluminescence (PL) and Ultra Violet-Vis near Infra measurement studies were carried out to optical properties and band gap of the materials. The band gaps of the materials were observed to be 2.47 eV for pure CdO, 2.32 eV for metals doped CdO which were appraise from Tauc’s plot. The average particle diameter of CdO nanoparticles was measured in the nanometer range using a dynamic light scattering (DLS) particle size analyzer. The magnetic properties to express vibrating sample magnetometer studies (VSM). The uppermost electrochemical capacitance implementation is using Cyclic Voltammetry analysis, which indicates capable electrode materials for electrochemical super capacitor applications.

Structural and Photocatalytic Studies on Oxygen Hyperstoichiometric Titanium-Substituted Strontium Ferrite Nanoparticles

Doping of ferrites is an important domain of research for their application as photocatalysts. In the present work, the effect of Ti4+ substitution on the structural and photocatalytic properties of strontium ferrite nanoparticles (NPs) is studied. Ternary doped Sr1−xTixFe2O4+δ ferrite NPs (x = 0.0–1.0) were synthesized by sol–gel methodology. Tetravalent Ti4+ ions caused oxygen hyperstoichiometry and enhancement in the surface area from 44.3 m2/g for SrFe2O4 NPs to 77.6 m2/g for Sr0.4Ti0.6Fe2O4+δ NPs. The average diameter of NPs ranged between 25–35 nm as revealed by TEM analysis. The presence of two sextets in the Mössbauer spectrum of pristine SrFe2O4 and Ti4+-substituted ferrite NPs and a paramagnetic doublet in the TiFe2O5 confirmed their phase purity. The photocatalytic potential of pure and Ti4+-substituted ferrite NPs was studied using nitroaromatic compounds, viz. pendimethalin, p-nitrophenol and Martius yellow, as model pollutants. Doped ferrite NPs with a composition of Sr0.4Ti0.6Fe2O4+δ NPs showed the highest degradation efficiency ranging from 87.2% to 94.4%. The increased photocatalytic potential was ascribed to the lowering of band gap (Eg) from 2.45 eV to 2.18 eV, a fourfold decrease in photoluminescence intensity, increased charge carrier concentration (4.90 × 1015 cm−3 to 6.96 × 1015 cm−3), and decreased barrier height from 1.20 to 1.02 eV. O2●− radicals appeared to be the main reactive oxygen species involved in photodegradation. The apparent rate constant values using the Langmuir–Hinshelwood kinetic model were 1.9 × 10−2 min−1, 2.3 × 10−2 min−1 and 1.3 × 10−2 min−1 for p-nitrophenol, pendimethalin and Martius yellow, respectively. Thus, tuning the Ti4+ content in strontium ferrite NPs proved to be an effective strategy in improving their photocatalytic potential for the degradation of nitroaromatic pollutants.

Fabrication and photoresponsive characteristics of ZnO film for ultraviolet ZnO/porous Si photodetector: The effect of post-processing treatment

This article demonstrates a well-designed fabrication process of ultraviolet (UV) ZnO/porous Si photodetector as a function of post-processing temperature. The structural and optical features of the deposited ZnO layers were thoroughly elucidated through which a robust correlation between the post-processing temperature and the addressed characteristics were established. Particularly, a decrease in the attained energy bandgap from 3.3 eV to 3.22 eV was obtained upon increasing the treatment temperature from 600 °C to 800 °C; the morphological analysis revealed the occurrence of average nanoparticle diameters of 69 nm and 64 nm, respectively. Continuously, the fabricated devices also demonstrated a well-established relation with the applied post-processing temperature wherein relatively high photoresponsivity and specific detectivity were attained at high temperature. Specifically, the photoresponsivity and specific detectivity values were observed to be 5.6 (μA/mW) and 1.8×1011 Jones at 25mW/cm2 illumination power using treatment temperature of 800 °C, respectively. In the meanwhile, the response time of the proposed device was estimated to be ∼300ms.

Electron transfer dynamics and electrocatalytic oxygen evolution activities of the Co3O4 nanoparticles attached to indium tin oxide by self-assembled monolayers.

The Co3O4 nanoparticle-modified indium tin oxide-coated glass slide (ITO) electrodes are successfully prepared using dicarboxylic acid as the self-assembled monolayer through a surface esterification reaction. The ITO-SAM-Co3O4 (SAM = dicarboxylic acid) are active to electrochemically catalyze oxygen evolution reaction (OER) in acid. The most active assembly, with Co loading at 3.31 × 10−8 mol cm−2, exhibits 374 mV onset overpotential and 497 mV overpotential to reach 1 mA cm−2 OER current in 0.1 M HClO4. The electron transfer rate constant (k) is acquired using Laviron’s approach, and the results show that k is not affected by the carbon chain lengths of the SAM (up to 18 -CH2 groups) and that an increase in the average diameter of Co3O4 nanoparticles enhances the k. In addition, shorter carbon chains and smaller Co3O4 nanoparticles can increase the turn-over frequency (TOF) of Co sites toward OER. The Co3O4 nanoparticles tethered to the ITO surface show both a higher number of electrochemically active Co sites and a higher TOF of OER than the Co3O4 nanoparticles bound to ITO using Nafion.

Resolved simulations of single iron particle combustion and the release of nano-particles

We present a numerical study of the combustion of single iron particles in an O2–N2 atmosphere. By resolving the full boundary layer, mass and heat transfer are accurately modeled, including Stefan flow. Only the conversion of Fe to FeO is taken into account and evaporation is implemented to investigate the formation of nano-sized iron-oxides products. Temperature- and composition-dependent heat capacity and density are used and phase transitions from solid to liquid (and vice-versa) are accounted for by the apparent heat capacity method. The model is validated by comparing the time to maximum temperature (tmax) and the maximum temperature (Tmax) of a 40 and 50 µm particle in an O2–N2 atmosphere with experiments. The current model, which assumes infinitely fast internal transport, can well estimate the maximum particle temperature and the time to reach this maximum temperature, but it does not capture the particle size effect on the maximum temperature. Even though the particle temperature stays below its boiling temperature, a small but non-negligible amount of mass is lost due to evaporation of the particle. Evaporation of the particle and oxidization of the gaseous Fe-containing species in the boundary layer limit the maximum temperature of the particle when increasing the oxygen concentration. By means of a sectional model, the formation and growth of the iron oxide nano-particles is numerically investigated. It is shown that somewhat further downstream of the particle, the volume fraction of nano-particles attains a maximum. An average nano-particle diameter of 40 nm is found at t/tmax=1 in the wake of a 50 µm iron particle burning at 21% oxygen concentration.

Advanced quantitative analysis of colloidal solution of metal nanoparticles produced by laser ablation in liquids

The diameter of laser synthesized colloidal nanoparticles can be derived from a volume of ablated material and absorbance at surface plasmon resonance wavelength. The origin of such nanoparticles’ diameter is studied in this work. The study is based on Beer-Lambert law where nanoparticle size-distribution and UV-Vis photoabsorbance data are used. Theoretically modeled diameter is verified by independent integral approach proving that simple model derived in our previous work is by most means usable for determination of diameter of laser synthesized nanoparticles in colloidal solution with sizes less than SPR wavelength. Here is also presented the mathematical proof which indicates that in monodisperse limit, under assumption that size-distribution of synthesized nanoparticles can be described by log-normal function, diameter obtained by simple analytical model is in fact mode diameter (most frequent diameter) of size-distribution. Furthermore, it is shown that mode diameter of size-distributions can be obtained from volume average diameter of nanoparticles over experimentally determined diameter distribution as well as from number average diameter of nanoparticles over the same diameter distribution by multiplication of those diameters with shift factors depended only on standard deviation of log-normal distribution. This is verified for size-distributions obtained independently by AFM, TEM and DLS techniques and is proposed to be universal property of log-normal distribution function.

The impact of laser energy on the photoresponsive characteristics of CdO/Si visible light photodetector

In this article, cadmium oxide (CdO) was deposited using pulsed laser deposition approach on porous silicon (Si) wafer for visible light photodetector application, through which a series of devices were proposed as a function of the deposition energy. The microstructural as well as optical characteristics of the prepared film/s were demonstrated, respectively, using x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and ultraviolet visible light spectroscopy (UV–Vis) analysis. In details, the UV–Vis analysis revealed the occurrence of optical band gaps within the range of 2.38–2.42 , while an average nanoparticle diameter was found to be 45 using FE-SEM technique. This in turn demonstrated a sound relation with the photoresponsive behavior of the attained photodetectors. A photoresponsivity and specific detectivity of 1.9 and Jones were attained using 700 laser energy. In the meanwhile, the estimated response/recover time of the addressed laser energy was found to be 300 and 340 , respectively. The photo-responsive characteristics of the fabricated devices were found to be in positive linear correlation with the applied laser energy.

Fe0.5Co0.5-Co1.15Fe1.15O4/carbon composite nanofibers prepared by solution blow spinning: Structure, morphology, Mössbauer spectroscopy, and application as catalysts for electrochemical water oxidation

In this work, we report the synthesis of Fe0.5Co0.5-Co1.15Fe1.15O4/carbon composite nanofibers by solution blow spinning (SBS) and study their structure, morphology, and catalytic activity toward the oxygen evolution reaction (OER, electrochemical water oxidation) in an alkaline medium. The solution blow spun fibers, prepared using nitrate precursors (Fe and Co) and poly(vinyl pyrrolidone, PVP), were calcined at 620 °C for 1 h in argon atmosphere. The thermogravimetric test shows that the stabilization of mass loss and the formation of the compound occur at ∼600 °C. X-ray diffraction revealed the presence of two crystalline phases, Fe0.5Co0.5 and Co1.15Fe1.15O4, with crystallite sizes of 16.5 nm and 18.1 nm, respectively. Scanning and transmission electron microscopies show that the average fiber and nanoparticle diameters are 362 nm and 28.41 nm, respectively. The quantification of Fe0.5Co0.5 and Co1.15Fe1.15O4 phases determined by the Rietveld refinement agrees well with the relative absorption area (RAA) values obtained by Mössbauer spectroscopy. Electrochemical analyses of Fe0.5Co0.5-Co1.15Fe1.15O4/carbon composite nanofibers supported by commercial Ni foam reveal a low overpotential value of η = 308 mV at 10 mA cm−2 and only 400 mV to generate 450 mA cm−2. The chronopotentiometry test over 15 h indicates that Fe0.5Co0.5-Co1.15Fe1.15O4/carbon nanofibers have excellent chemical and mechanical stability for their use as electrodes for water oxidation.

Investigating the Molecular Mechanism of Optimized Bio Denitrification by Thiobacillus denitrificans in the Presence of Metal Nanostructures in Bioreactor

Nitrate contamination of groundwater and surface water has become a serious problem. Zero-capacity iron (Fe0) nanoparticles are of great interest for the purification of toxic compounds from water. The aim of this study was to synthesis and optimize starch-coated “St” and carbon quantum dot-coated “CQD” Fe0 nanoparticles (St-Fe0 and CQD-Fe0) and investigate their role in bio denitrification and expression of nirS, narH and recA genes using the q-PCR technique. This study has a non-treatment control. The structural and morphological characteristics of nanoparticles were determined by XRD, TEM, FE-SEM and FTIR. Two important operating parameters including temperature (̊C) and nanoparticles concentration (g l−1) influencing the bio denitrification process of Thiobacillus denitrificans in the presence of nanoparticles were optimized by the response surface method (RSM). The FTIR spectrum confirmed the formation of CQD-Fe0 bonds. The average diameter of CQD-Fe0 nanoparticles was in the range of 29.31 to 38.32 nm. Denitrification in the presence of St-Fe0 and CQD-Fe0, with increasing temperature (35 C°) and nanoparticle concentration (1 g l−1), was 71.42% and 73.43%, respectively. After determining the optimal conditions, bio denitrification in the presence of nanoparticles at different concentrations of nitrate was investigated in a moving bed bioreactor. According to the results, in the discontinuous conditions, bio denitrification efficacy of Thiobacillus denitrificans in the presence of St-Fe0 and CQD-Fe0 nanoparticles was 80.10% and 79.83%, respectively. While in the bioreactor, denitrification efficacy in the presence of St-Fe0 and CQD-Fe0 was increased to 94.07% and 95%, respectively. In other words, bio denitrification of microorganisms in the moving bed bioreactor in the presence of CQD-Fe0 was higher compared to St-Fe0. The results of this study showed that the expression of all three genes nirS, narH and recA in cells treated with St-Fe0 and CQD-Fe0 significantly increased compared to the control group, which indicates the high impact of these nanoparticles, especially CQD-Fe0 on bio denitrification of this microorganism.

Study of Phase Transformation, Structures, Morphology, and Vibration of Ni-Zn-Co Ferrites Nanoparticles due to Annealing Temperature

The good physical and chemical properties of metal ferrite nanoparticles can be used as potential materials when applied. This study aims to explore the physical and chemical properties, such as phase, structure, morphology, and vibration of Ni-Zn-Co ferrites nanoparticles annealed at different temperatures. Ni0.4Zn0.5Co0.1Fe2O4 nanoparticles were synthesized by coprecipitation method and characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared (FTIR) Spectroscopy to determine their structure, morphology, and vibration. Overall, all samples showed spinel cubic structures. In addition, XRD analysis showed the phase transformation from magnetite to hematite by increasing the temperature. The increase of annealing temperature leads to the larger average size of nanoparticles which were estimated by analyzing TEM images. The average diameter of nanoparticles with annealing temperature of 600°C was (10.9 + 0.5) nm and the average diameter of nanoparticles with annealing temperature of 1000°C was (18.6 + 4) nm. FTIR measurements between (4000 – 400) cm-1 confirmed the absorption band in the spectrum. The FTIR spectra of the nanoparticles confirmed the presence of metal ion vibrational bands located at octahedral and tetrahedral sites in 418 cm-1 to 696 cm-1. This implies that Ni-Zn-Co ferrites has truly the spinel cubic structures considering their absorption characteristics at about (500 – 600) cm-1.

Synthesis, characterization and application of calcium peroxide nanoparticles as a novel adsorbent for removal of malic acid from aqueous solutions

This study aims to propose a novel adsorbent for removal of malic acid from aqueous solutions. In this context, calcium peroxide (CaO2) nanoparticles as novel adsorbent were synthesized, characterized, and assessed the efficiency of in malic acid removal. Followed this, kinetic, thermodynamic, and equilibrium studies were conducted. The average particle diameter and surface area of CaO2 nanoparticles have been found to be 34.77 nm and 13.58 m2.g−1, respectively. The maximum adsorption capacity of CaO2 nanoparticles for malic acid has been determined as 596.86 mg.g−1. The results showed that CaO2 nanoparticles are effective adsorbent in removing malic acid from aqueous solutions.

In vitro cytotoxicity, macromolecular interaction and antioxidant potential of dual coated selenium nanoparticles.

The present research focuses on synthesizing selenium nanoparticles (Se NPs) coated with Methionine and Folic acid. selenium-methionine-folate nanoparticles (Se-Met-Fa NPs) were prepared by the chemical precipitation method. These were characterized by UV-Vis spectroscopy, FTIR, X-ray diffraction, Zeta potential, ICP-AES, TEM, and Raman spectroscopy. The average diameter of nanoparticles was determined by TEM was 50 nm. In Vitro viability of cells exposed to Se-Met-Fa NPs were studied using MTT and AO/EB assay. Approximately 80% of cells were viable at 100 μg/ml concentration after 24 h of incubation, suggestive of the safety of nanoparticles. Macromolecular interaction studies were carried out with plasmid DNA and Bovine serum albumin (BSA) protein. UV-Vis Spectroscopy showed ground state complex formation of Se-Met-Fa NPs with BSA. Intrinsic fluorescence of BSA was quenched by Se-met-Fa NPs via Static quenching and was observed under Spectro-fluorimetry. Conformational structural change in α-Helices of BSA was observed to be 4.4% after the interaction with Se-Met-Fa NPs, and it was studied using CD spectroscopy. At 250 μg/ml Se-Met-Fa NPs prevented oxidative damage of Plasmid DNA. The total antioxidant property of Se-Met-Fa NPs expressed in terms of scavenging of free DPPH radicals. Ten micrograms per milliliter could inhibit 41% of DPPH, proving its scavenger role at the lowest concentration. Nanoparticles comprising antioxidant semi-conducting cores and encapsulated by biomaterials that are highly bioavailable can be promising therapeutic agents for inflammation and oxidative stress disorders studies.

The investigation of the average diameter of the SiO2 nanoparticles effect on the oil displacing efficiency from the pore in the rock formation using nanosuspension as a displacing agent

The numerical investigation of the nanofluid flow, which displaced the oil, in a microchannel was carried out. The effect of the average diameter of the SiO2 nanoparticles on the oil displacing efficiency by nanofluids for different sizes of microchannel at various Reynolds numbers was studied. A T-shaped microchannel with a vertical channel, called a pore channel, which imitated the pore in the rock formation was considered as a computational domain. The main flow channel width and height were 200 µm. The width and height of the pore channel were varied in the range from 100 µm to 800 µm. The Reynolds number varied from 0.1 to 100. The oil recovery coefficient, which is defined as the ratio of the displacing volume of oil from the pore to the volume of the pore was considered as the main studied characteristic. The nanofluid is considered a single-phase fluid with experimentally obtained properties. The mass concentration of SiO2 nanoparticles was 0.5%. The average diameters of nanoparticles were 5 nm, 18 nm, and 50 nm. It was found, that the oil recovery coefficient increased with a decrease in the average diameter of nanoparticles. It was obtained that the nanofluid can enhance the oil recovery several times compared to pure water.