Average Size Of Nanoparticles Research Articles

Phytomediated zinc oxide and sulfur nanoparticles for management of soft-rot causing pathogenic fungi in ginger

Diseases management has been the greatest challenge to agriculture leading to huge crop failure, represented in low-profit production. Phytopathogenic fungi are among pathogens causing a variety of agricultural diseases. Various nanoparticles (NPs) have previously been employed to combat phytopathogenic fungi. Post-harvest deterioration due to fungal invasion is the most imperative cause of loss of ginger (Zingiber officinale) production. In the present study, four fungal pathogens isolated from soft-rot infected ginger were identified as Pythium spp. (isolate I and II), one Fusarium sp. (isolate III) and one Aspergillus sp. (isolate IV). Moringa oleifera mediated zinc oxide (ZnONPs) and sulfur nanoparticles (SNPs) were characterized by UV–Visible spectrophotometry and showed absorption maxima at 356 nm and 295 nm. Average size of NPs under Nanoparticle Tracking Analyzer was 78 nm and 26 nm respectively, confirmed by FESEM. Stable NPs with zeta potential of −14.1 mV (Standard deviation = 4.51 mV) and −21.1 mV (Standard deviation = 9.56 mV) were synthesized. FTIR detected the presence of various functional groups in NPs. In vitro antifungal activity was assessed by Kirby-Bauer disc diffusion assay and MIC values compared to antibiotic ketoconazole and fungicide mancozeb. Time kill assay represented the minimum time required by selected NPs to inhibit the growth of test pathogenic fungi. ZnONPs and SNPs can be used for further antifungal studies in the field as novel nanofungicides. Extrapolated and uncontrolled use can lead to the inhibition of germination, reduction in photosynthesis rate, and disruption of the plant roots. Thorough small-scale experimentation is necessary before commercialization.

Insights on the effect of process conditions on the optical properties of silver ion exchanged soda-lime silicate glass

The effects of ion exchange time and temperature on the optical properties and plasmonic response of silver ion exchanged soda-lime silicate glass were investigated using scanning electron microscopy (SEM) in energy dispersive spectrometry (EDS) configuration, m-lines spectroscopy, photoluminescence (PL) spectroscopy, and UV–visible absorption spectroscopy. SEM analyses in EDS mode provided profiles of silver oxide molar concentration. These profiles were directly correlated to the silver diffusion coefficient using an adjustment procedure. The effective indices of ion exchanged glasses measured by the standard prism coupling technique (m-lines) allowed access to refractive index distributions in ion exchange regions. These ion-exchanged glasses underwent evaluation to determine their potential suitability for use in multimode planar systems. The PL results acquired after ion exchange demonstrated that the creation of Ag0 atoms from Ag+ ions was responsible for the decline and quenching of PL intensity at ion exchange times and temperatures increase. Silver nanoparticles were generated in the samples subjected to ion exchange at 480 °C without the need for post-exchange treatments. The emergence of the surface plasmon resonance band around 427 nm in the optical absorption spectra confirmed the formation of Ag nanoparticles in annealed glasses. Estimates of the UV–visible absorption spectra indicated an average size of silver nanoparticles ranging from 1.8 to 2.4 nm.

Gamma-ray-elicited alterations in the structural, optical, and morphological attributes of spinel nickel cobaltite NiCo2O4

BackgroundIrradiation is thought to be the most effective approach to change the crystal structure and properties of solid materials. Higher energy gamma-irradiation may change the physical properties of semiconductor materials. Gamma irradiation is recognized as an effective method for altering the crystal structure and properties of solid materials. ObjectiveThe primary goal of this study was to assess how gamma irradiation affects different properties of spinel nickel cobaltite. Materials and methodsThe co-precipitation technique was operated to synthesize spinel nickel cobaltite. The synthesized spinel nickel cobaltite nanoparticles were subjected to gamma irradiation. The study employed gamma doses ranging from 40 KGy to 60 KGy. A gamma irradiator was used for this purpose. Changes induced in the structural, optical, and morphological properties of spinel nickel cobaltite had been investigated by XRD, UV–Vis spectroscopy, SEM, and FTIR. ResultsXRD revealed that the average crystalline size of nanoparticles was decreased with gamma irradiation. The band gap, Urbach energy, and extinction coefficient, real and imaginary components of dielectric constant using absorbance and transmittance spectra. The refractive index evaluated from the Moss relation increased from 2.31 to 2.46. The refractive index calculated from Van Vechan's relation increased from 2.60 to 2.78. Urbach energy values increased from 2.14 eV to 2.89 eV with an increased dosage of gamma. It was observed that all parameters were changed by gamma irradiation. SEM study showed that the grain size of particles was decreased with gamma doses. FTIR study verified the spinel-type structure of nickel cobaltite. ConclusionThe study aimed to shed light on the effects of gamma irradiation on spinel nickel cobaltite, with a focus on its structural, optical, and morphological properties. By using a combination of characterization techniques, the researchers can assess how gamma irradiation alters the material's properties and potentially tailor it for specific applications.

Synthesis of Silver Nanoparticles, Study of Structure, Properties and Applications in the Treatment of Wounds

Silver nanoparticles are used in many areas of medicine as part of antibacterial and wound-healing ointments and preparations. Research objectives: study the synthesis of silver nanoparticles, structure, properties and applications in the treatment of burn wounds. The synthesis of silver nanoparticles was performed by chemical precipitation. As synthesized silver nanoparticles have a cubic crystalline shape; the average size of nanoparticles is 18 nm. No skin-irritating effect of medicinal cosmetic gel containing silver nanoparticles was detected.

Environmental-related applications of ZnO nanopowders: Photocatalytic activity and photoluminescence response to ethanol

Zinc oxide (ZnO) and copper-doped zinc oxide (ZnO:Cu) nanopowders were synthesized via solvothermal methods using methanol and hexamethylenetetramine (HMTA). Undoped ZnO nanopowders underwent calcination in O2-rich and H2-rich atmospheres at 600 °C. Samples were studied by scanning electron microscopy, Brunauer–Emmett–Teller (BET) surface area analysis, X-ray diffraction (XRD), and Raman, photoluminescence (PL) and UV–vis absorbance spectroscopies. The doping and calcinations led to a reduction of the optical bandgap of the nanopowders, while their structure remained hexagonal wurtzite with some changes in lattice parameters and average nanoparticle sizes. The Cu2+ doping led to a BET surface area and violet PL component increase. Samples were also examined for environmental related applications, namely as photocatalyzers for dye degradation and as ethanol optical sensors. For photocatalytic activity in methylene blue degradation under UV, H2-rich calcined powders excelled, with a rate constant of −0.076 min−1, surpassing −0.057 min−1 (ZnO:Cu), −0.056 min−1 (O2-rich calcination), and −0.041 min−1 (as-grown ZnO). We propose that this improvement can be attributed to the formation of ZnO/Zn interfaces stemming from the reduction of surface interstitial zinc by H2 during calcination, in addition to the observed reduction of the ZnO bandgap. The doped nanopowders PL also showed excellent response when exposed to ethanol vapor.

Exploring Enhanced Hydrolytic Dehydrogenation of Ammonia Borane with Porous Graphene-Supported Platinum Catalysts.

Graphene is a good support for immobilizing catalysts, due to its large theoretical specific surface area and high electric conductivity. Solid chemical converted graphene, in a form with multiple layers, decreases the practical specific surface area. Building pores in graphene can increase specific surface area and provide anchor sites for catalysts. In this study, we have prepared porous graphene (PG) via the process of equilibrium precipitation followed by carbothermal reduction of ZnO. During the equilibrium precipitation process, hydrolyzed N,N-dimethylformamide sluggishly generates hydroxyl groups which transform Zn2+ into amorphous ZnO nanodots anchored on reduced graphene oxide. After carbothermal reduction of zinc oxide, micropores are formed in PG. When the Zn2+ feeding amount is 0.12 mmol, the average size of the Pt nanoparticles on PG in the catalyst is 7.25 nm. The resulting Pt/PG exhibited the highest turnover frequency of 511.6 min-1 for ammonia borane hydrolysis, which is 2.43 times that for Pt on graphene without the addition of Zn2+. Therefore, PG treated via equilibrium precipitation and subsequent carbothermal reduction can serve as an effective support for the catalytic hydrolysis of ammonia borane.

On the Structural and Molecular Properties of PEO and PEO-PPG Functionalized Chitosan Nanoparticles for Drug Delivery.

Chitosan nanoparticles (CS-NPs) are currently under investigation for a wide range of applications in nanomedicine. We investigated the structural, morphological, and molecular properties of CS-NPs synthesized via ionic gelation and designed specifically for drug delivery. The CS-NPs were prepared at concentrations ranging from 0.25 to 1.0% w/v. The 1.0% w/v CS-NPs were also functionalized with polyethylene oxide (PEO) alone and with a diblock copolymer of PEO and polypropylene glycol (PPG). The average nanoparticle size determined from TEM imaging is in the 11.3 to 14.8 nm range. The XRD and TEM analyses reveal a semi-crystalline structure with a degree of crystallinity dependent upon the nature of CS-NP functionalization. Functionalizing with PEO had no effect, whereas functionalizing with PEO-PPG resulted in a significant increase in the crystallinity of the 1.0% w/v CS-NPs. Additionally, the CS/TPP concentration (CS:TPP fixed at a 1:1 ratio) did not impact the degree of crystallinity of the CS-NPs. FTIR analysis confirmed the incorporation of TPP with CS and an increase in hydrogen bonding in more crystalline CS-NPs.

Selectivity control between reverse water-gas shift and fischer-tropsch synthesis in carbon-supported iron-based catalysts for CO2 hydrogenation

CO2 hydrogenation to chemicals and fuels has the potential to alleviate CO2 emissions and displace fossil resources simultaneously via consecutive RWGS and FTS reactions, also known as CO2-FTS. As Fe-based catalysts are active and selective for both reactions, their bifunctionality requires a delicate balance between the RWGS and FTS. In this work, we investigated the thermodynamic constraints of RWGS and CO2-FTS, the influence of CO2 conversion on selectivity and the influence of Fe nanoparticle size within the range of 4.7 to 10.3 nm. An inert carbon support was selected to rule out metal-support interaction and promoting effects of the support. Catalytic performance was evaluated at 300 °C, 11 bar, H2/CO2/Ar = 3/1/1, 600 to 72000 mL·gcat-1·h-1. At a CO2 conversion level below RWGS equilibrium conversion of 23 %, RWGS was found to be the primary and dominant reaction. No primary Sabatier reaction was observed. At higher CO2 conversion till the CO2-FTS threshold of 42 %, the secondary FTS reaction became dominant. Notably, a non-linear relation between CO2 conversion and CO selectivity was discovered. Comparing two catalysts with identical 5 wt% Fe loading but different average Fe nanoparticle size (6.6 and 8.4 nm), the 8.4 nm Fe catalyst was at least two times more active than the 6.6 nm Fe catalyst. In situ Mössbauer spectroscopy suggested a positive correlation between particle size, carburization and selectivity towards long-chain hydrocarbons. For these potassium-promoted carbon-supported Fe-based catalysts, nanoparticles of at least 8 nm are required for the formation of Fe carbides and improved reactivity.

Cu-doped LaFe1-xCuxO3 perovskites nano-crystallites for enhanced VOCs detection

Highly sensitive, and versatile metal oxide semiconductors, including perovskites, are used in gas sensors for environmental, and safety applications. This study described the substitution of Cu for Fe in LaFe1-xCuxO3 nanostructured perovskites, denoted as Cx’s, using Pechini sol-gel method at 600 °C, to detect the volatile organic compounds (VOCs). Characterization techniques, including TGA/DTA, XRD, BET, FE-SEM/EDS, Raman, PL, XPS, UV-DRS, FTIR, TPD-O2 and ethanol chemisorption showed significant enhancements in physicochemical, and gas sensing properties of LaFeO3 perovskites, upon copper doping in its structure. The responses to ethanol improved, the average crystallite and nanoparticle sizes decreased, and the electrical conductivity increased as the perovskite copper content increased to x = 0.6. The crystallite size of 20.5 nm for LaFeO3 decreased to 12.7 nm for LaFe0.4Cu0.6O3. The SC0.6 thick film gas sensor showed high potential in the VOCs detection, with best responses of 17 for ethanol, 18 for acetone, and 16 for acetaldehyde when exposed to each of 300 ppm at 300 °C. At these conditions, the response and recovery times of highly stable SC0.6 sensor for ethanol gas were 4 and 11 min, respectively.

Comparing silver and gold nanoislands’ surface plasmon resonance for bisacodyl and its metabolite quantification in human plasma

Gold and silver nanoparticles have witnessed increased scientific interest due to their colourful colloidal solutions and exceptional applications. Comparing the localized surface plasmon resonance (LSPR) of gold and silver nanoparticles is crucial for understanding and optimizing their optical properties. This comparison informs the design of highly sensitive plasmonic sensors, aids in selecting the most suitable nanoparticles for applications like surface-enhanced infrared spectroscopy (SEIRA) and biomedical imaging, and guides the choice between gold and silver nanoparticles based on their catalytic and photothermal properties. Ultimately, the study of LSPR facilitates the tailored use of these nanoparticles in diverse scientific and technological applications. Two SEIRA methods combined with partial least squares regression (PLSR) chemometric tools were developed. This development is based on the synthesis of homogeneous, high-dense deposited metal nanoparticle islands over the surface of glass substrates to be used as lab-on-chip SEIRA sensors for the determination of bisacodyl (BIS) and its active metabolite in plasma. SEM micrographs revealed the formation of metallic islands of colloidal citrate-capped gold and silver nanoparticles of average sizes of 29.7 and 15 nm, respectively. BIS and its active metabolite were placed on the nanoparticles’ coated substrates to be directly measured, then PLSR chemometric modelling was used for the quantitative determinations. Plasmonic citrate-capped gold nanoparticle substrates showed better performance than those prepared using citrate-capped silver nanoparticles in terms of preparation time, enhancement factor, PLSR model prediction, and quantitative results. This study offers a way to determine BIS and its active metabolite in the concentration range 15–240 ng/mL in human plasma using inexpensive disposable glass-coated substrates that can be prepared in 1 h to get results in seconds with good recovery between 98.77 and 100.64%. The sensors provided fast, simple, selective, molecular-specific and inexpensive procedures to determine molecules in their pure form and biological fluid.

Iron oxide immobilized lipase bioconjugate platform for sensing of triglycerides in biological samples

As a major biomarker in several health conditions, an efficient detection strategy to monitor triglyceride (TGs) level is imperative. In this study, enzyme-based triglyceride detection platform is reported by employing surface functionalized iron oxide nanoparticles (IONPs). The green synthesis method (using green tea extract) was adopted for the synthesis of IONPs exhibiting magnetic properties. The synthesized nanoparticle was characterized using SEM, FT-IR and UV–Vis spectroscopy. The SEM data confirmed the synthesis of spherical nanoparticles with an average size of 200 nm. Moreover, the additional coating of aspartate made the immobilization of biomolecule lipase on the IONPs more stable and was confirmed via the acquired data from SEM. The surface functionalization of IONPs using aspartic acid was confirmed by FT-IR spectra. Enzyme immobilization was performed by adding glutaraldehyde as the crosslinker, leading to formation of a nanoparticle-enzyme bioconjugate. The resultant bioconjugate was used for colorimetric estimation of triglyceride in biological samples using palmitic acid as the standard and methyl red as the indicator. The designed bioconjugate exhibited accuracy of 7.5 folds. The nanoparticle-enzyme bioconjugate platform renders a simple, economical, and easy-to-use biosensing approach with higher stability and activity when compared to its soluble counterpart.

Structure and optical characterization of chitosan-chitin/Ag nanocomposite thin films

Chitin and its derivatives are common natural polymers that are widely used in various technological fields. In recent years, considerable attention has been paid to the preparation of polymer nanocomposites based on metal nanoparticles (NPs). Chitin/chitosan-based composites due to high antibacterial activity are suitable for application in related food storage, textile industries. This paper presents an effective and simple method of obtaining chitosan-chitin copolymer/Ag nanocomposites with an extremely high content of metal nanoparticles. The structure and morphology of the synthesized nanocomposites were investigated using X-ray diffractometry, Fourier-transform infrared spectroscopy, electron microscopy, and their optical properties were studied using UV-VIS spectroscopy as well as spectral ellipsometry. It was ascertained that the resulting nanocomposite films are characterized by a uniform distribution of spherical silver nanoparticles, the sizes of which increase (from 55 up to 143 nm) with increasing the Ag+-ions concentration in the reaction mixtures. The optical absorption spectra of nanocomposites are characterized by the presence of an absorption maximum within the range 458…525 nm, which confirms the formation of Ag NPs. A monotonous increase in the values of the energies of optical transitions was observed in the process of increasing the average size of NPs

Effect of Ag-doping on morphology, structure, band gap and photocatalytic activity of bio-mediated TiO2 nanoparticles

The production of nanoparticles using biogenic synthesis techniques is becoming more prominent due to its diverse applications. In this research, the extract from mango leaf was utilized to fabricate a green method for producing Ag-doped and undoped TiO2 nanoparticles that is non-toxic, economical, and environmentally favorable. Titanium isopropoxide (TTIP) was used as a precursor for Ag-doped and undoped TiO2 nanoparticle production, where the concentrations of the dopant material silver were 2.5 and 3%. Acquired undoped and Ag-doped TiO2 nanoparticles were characterized using several analytical techniques. The morphological, structural, and photocatalytic activity were evaluated using XRD, SEM, EDX, and UV–Vis spectroscopy. In the XRD analysis, undoped and Ag-doped TiO2 nanoparticles indicated the formation of an anatase phase, but there was no rutile phase. The photocatalytic activity and nanoparticles’ band gap were assessed using UV–Vis spectroscopy. The UV–Vis Spectroscopy also revealed a reduced band gap energy (Eg) of Ag-doped TiO2 nanoparticles than the undoped TiO2 Nanoparticles (NPs). The development of photocatalytic activity and features of the “Red-shift” characteristic was established by the progressive photo-degradation of Methylene Blue (MB). The SEM analysis revealed that Ag-doped TiO2 nanoparticles showed more agglomeration than the undoped sample. The average particle size of undoped TiO2 nanoparticles was 38.33 nm, and the size gradually increased for 2.5% and 3% Ag-doping. Utilizing EDX analysis, the doping of Ag+ in the TiO2 lattice structure was confirmed. We can predict from the findings that utilizing biosynthesized TiO2 nanoparticles can be an excellent option for water purification, dye-sensitized solar cells, photo-degradation process, etc., in the long run.

Synthesis and Characterization of Aluminum Oxide Nanoparticles Prepared by Two Different Cold Plasma Jet Methods

In this paper, a cold plasma system utilizing a high voltage of 13.5 kV of alternative (AC) and direct current (DC) was used under atmospheric pressure with argon (Ar)-gas at a flow rate of 2.5 l/min and a flowing time of 4 min to synthesize aluminum oxide (AlO) nanoparticles (NP). From the results, when DC was used, it was found that the absorption spectrum starts at 303 nm and gradually falls to 870 nm. With AC, the absorption spectrum was at 330 nm and then began to fall to 902 nm. The energy gap when utilizing DC and AC was 3.49 and 3.44 eV respectively. The analysis of the X-ray diffraction (XRD) patterns showed the structure of the NPs was amorphous, matching the pattern 42-1746. At DC, the average size of NPs formed, as deduced from the XRD pattern, was 29.56 nm, and it was very close to what appeared in the field emission scanning electron microscopy (FESEM) images, in which the apparent NP size ranged between 20 and 50 nm. The XRD test gave an average NP size of 38.21 nm in AC, while the FESEM images showed a size range of 20 - 60 nm. At dc, the AlO NPs were aggregated and interconnected, and each set was connected to another set, as shown in the FESEM images. At AC, the shape of the synthesized AlO NPs was quasi-spherical, with slightly elongated particles connected.

Biogenic ZnO Nanoparticles Derived from Garcinia gummi-gutta Leaves: Synthesis, Characterization and its Multifaceted Applications

The current study focused on the bioreduction synthesis of ZnO nanoparticles using Garcinia gummi-gutta leaf extracts. The UV-vis analysis of the nanoparticles has reported the formation of an SPR peak at 379 nm. The functional groups taking part in the reduction reaction were analyzed using the FTIR technique and the average crystalline size of ZnO nanoparticles were found to be 22.27 nm from XRD measurements. The SEM and TEM images revealed the hexagonal shape of the nanoparticles with an average size 72.78 nm and 71.91 nm, respectively. Further, the synthesized nanoparticles were reported to be efficient degradation reactive textile dyes. The photodegradation results reported 92-100% degradation of the reactive dyes within 80-320 min. The antibacterial efficacy of the nanoparticles was investigated and the MIC of the nanoparticles was found to be 100 µg/mL. The synthesized ZnO nanoparticles have exhibited significant cytotoxic effects on the MCF and HEP-G2 cell lines.

Irradiation Time Optimization on Photocatalytic Activity of Nanoparticles MgO from Dolomite Bangkalan

Dolomite is a type of sedimentary rock material that is often found in the Bangkalan Madura area. This dolomite has a higher MgO compound content than in the other areas, namely 40 %, but its utilization has only been as fertilizer and building materials. For this reason, this research aims to determine the characteristics of MgO nanoparticles and their application in photocatalytic with visible light irradiation. The synthesis of MgO nanoparticles used the hydrochloric acid leaching method, and the results were characterized by X-ray diffraction, Fourier transform infrared, Scanning electron microscopy, Transmission electron microscopy, Raman spectroscopy, Photoluminescence, and Ultraviolet-visible spectroscopy. The results showed that the synthesized MgO nanoparticles had a periclase phase and were shaped like a spherical cube with an average nanoparticle size of 27 nm and an energy gap of 3.9 eV. The optical properties of the MgO nanoparticles showed quite strong luminescence at a Raman shift of 1,087.36 cm−1, which was associated with the type of vibrational waves in the atomic lattice, and there were surface defects on the surface of the MgO nanoparticles, namely in the emission spectra of 720.06 and 740.39 nm originating from oxygen vacancies (F-center) and Mg vacancies (V-center). The photocatalytic activity of MgO nanoparticles in visible light showed the optimum time to degrade 30 ppm methylene blue dye in 360 min and yielded a degradation percentage of 99 %. Therefore, MgO nanoparticles could be used for processing industrial dye waste using visible light. HIGHLIGHTS The synthesis of MgO Nanoparticles from Bangkalan dolomite used the hydrochloric acid leaching method The presence of nanocrystallite size, crystal defects, and oxygen vacancies in MgO nanoparticles can increase photocatalytic activity MgO nanoparticles can degrade methylene blue dye with an optimum time of 360 minutes under visible light irradiation GRAPHICAL ABSTRACT

Synthesis and Optimization of Bovine Serum Albumin Nanoparticles Immobilized with Antituberculosis Drugs

This study involved the synthesis of bovine serum albumin (BSA) nanoparticles immobilized with the antituberculosis drugs isoniazid (INH) and rifampicin (RIF) by the desolvation method. The primary objective was to explore the impact of varying concentrations of albumin, urea, cysteine, rifampicin, and isoniazid on the average size of nanoparticles, polydispersity, and the encapsulation efficiency of drugs. The study's outcomes affirm that alterations in the concentrations of these components influence nanoparticles’ parameters, highlighting their key role in optimizing the encapsulation process and enhancing the efficacy of tuberculosis drug delivery. The nanoparticles obtaned as a result of optimization demonstrated an optimal size of 231.2±1.2 nm with a polydispersity of 0.061±0.08. Encapsulation efficiency was 89% for rifampicin and 38.5% for isoniazid. The investigation of drug release kinetics from the polymer matrix revealed a gradual release pattern. Evaluation of the obtained nanoparticles by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) confirmed the successful incorporation of drugs into the polymer matrix. These findings highlight the potential of BSA nanoparticles as effective carriers for tuberculosis treatment, with implications for refining drug delivery strategies.

Effect of pH, Amount of Metal Precursor, and Reduction Time on The Optical Properties and Size of Zinc Oxide Nanoparticles Synthesized Using Aqueous Extract of Rhizomes of Acorus calamus

Nanoparticles possess various unique characteristics compared to the corresponding bulk materials. Large band gap, non-toxic nature, and multi-applicability are the worthwhile characteristics of zinc oxide to be synthesized and studied. The size of nanoparticles can be controlled by varying the different experimental conditions. This paper reports the synthesis of zinc oxide nanoparticles by using an aqueous extract of rhizomes of Acorus calamus, where the bio-components present in aqueous extract acted as reducing agents. The size and band gap energy of zinc oxide nanoparticles were studied by varying different parameters such as pH, concentration of the metal precursor, and reduction time. The variations in the size of nanoparticles were studied by UV-visible spectroscopy. FTIR showed phenolic compounds, primary amines, and amides (proteins/enzymes) as the functional groups responsible for the reduction of metal precursors to form nanoparticles. The surface morphology of nanoparticles was studied by FE-SEM image. The FE-SEM image displayed the formation of various shapes and agglomeration of the nanoparticles. XRD pattern revealed that the average size of zinc nanoparticles is 10 nm. In vitro antibacterial activity of ZnO nanoparticles has been assayed against gram-positive and gram-negative bacteria. The growth inhibitory activity of nanoparticles against different bacterial pathogens has also been determined

Influence of Dilution Upon the Ultraviolet-Visible Peak Absorbance and Optical Bandgap Estimation of Tin (IV) Oxide and Tin(IV) Oxde-Molybdenum(IV) Sulfide Solutions

The study investigated the constraints associated with the dilution technique in determining the optical bandgap of nanoparticle dispersion and modified nanocomposites, utilizing ultraviolet-visible absorbance spectra and Tauc plot analysis. A case study involving SnO2 dispersion and SnO2-MoS2 nanocomposite solutions, prepared through the direct solution mixing method, was conducted to assess the implications of dilution upon the absorbance spectra and bandgap estimation. The results emphasize the considerable impact of the dilution technique on the measured optical bandgap, demonstrating that higher dilution factors lead to shift in bandgap values. Furthermore, the study highlights that dilution can induce variations in the average nanoparticle sizes due to agglomeration, thereby influencing bandgap estimation. In the context of nanocomposites, the interaction between SnO2 nanoparticles and exfoliated MoS2 nanosheets diminishes with increasing dilution, leading to the estimated optical bandgap being primarily attributable to SnO2 nanoparticles alone. These observations underscore the necessity for caution when employing the dilution technique for bandgap estimation in nanoparticles dispersion and nanocomposites, offering valuable insights for researchers and practitioners in the field.

Enhancing Radiator Cooling with CuO Nanofluid Microchannels

The study explores in employing copper oxide (CuO) nanofluid as a cooling medium in the vehicle radiators. To simulate the heat transfer process, the microchannel is construct-ed using electron discharge machining (EDM) and a computational fluid dynamics (CFD) modeling is employed. UV-visible spectroscopy, scanning electron microscopy (SEM), and dynamic light scattering (DLS) are used to characterize the CuO nanofluid. CuO nanofluid surpasses water in the heat transfer capabilities, with a 40% improvement in thermal conductivity. The average size of CuO nanoparticles was determined via DLS to be 485.1 nm. The heat transfer coefficient of CuO nanofluid is 5366 W/m2K, which is 116% larger than that of water. The increased heat transfer capabilities of CuO nanofluid microchannel flow indicate to its potential as a viable replacement for conventional radiators in the automotive applications. Lower engine temperatures, increased fuel efficiency, and longer engine lifespan may result from improved cooling performance. Due of the small size of microchannels, more efficient and space-saving radiators for automobiles are conceivable. More research is needed to improve the microchannel design as well as to realize the practical benefits of CuO nanofluids in car cooling systems