Diameter Of Nanoparticles Research Articles

Numerical investigation and artificial brain structure-based modeling to predict the heat transfer of hybrid Ag/Au nanofluid in a helical tube heat exchanger

In recent years, due to the low thermal coefficients of common fluids and the increase in size and cost of heat exchangers, technologies for improving heat transfer and reducing dimensions have been developed and widely used in industries such as refrigeration, cooling of processing cells, chemical industries, and more. Previously, increasing heat exchange capacity in heat exchangers was achieved by altering parameters such as boundary conditions, flow geometry, heat exchanger geometry, or changing the type of fluid. Additionally, apart from the use of nanofluids, various other operational methods can be employed to improve the thermal performance of heat exchangers. Accordingly, considering the combination of the aforementioned innovative techniques, this study presents the modeling of flow and heat transfer inside helically coiled tube heat exchangers under the flow of nanofluids containing nickel, gold, silver, and gold/silver hybrid nanoparticles using numerical and artificial intelligence methods. In this study, the effect of variations in the inner diameter of the coiled tube and the volume fraction of nanoparticles was examined. The results showed that increasing the inner diameter and volume fraction of nanoparticles leads to an increase in heat transfer coefficient and Nusselt number, while the friction factor decreases with an increase in Reynolds number and increases with an increase in diameter and volume fraction. Finally, the accuracy and validity of the model were evaluated using statistical parameters and experimental results, which showed a 99.9% level of agreement between the predicted and experimental outcomes.

Exploring the Potential of Lapatinib, Fulvestrant, and Paclitaxel Conjugated with Glycidylated PAMAM G4 Dendrimers for Cancer and Parasite Treatment.

Fulvestrant (F), lapatinib (L), and paclitaxel (P) are hydrophobic, anticancer drugs used in the treatment of estrogen receptor (ER) and epidermal growth factor receptor (EGFR)-positive breast cancer. In this study, glycidylated PAMAM G4 dendrimers, substituted with F, L, and/or P and targeting tumor cells, were synthesized and characterized, and their antitumor activity against glioma U-118 MG and non-small cell lung cancer A549 cells was tested comparatively with human non-tumorogenic keratinocytes (HaCaT). All cell lines were ER+ and EGFR+. In addition, the described drugs were tested in the context of antinematode therapy on C. elegans. The results show that the water-soluble conjugates of G4P, G4F, G4L, and G4PFL actively entered the tested cells via endocytosis due to the positive zeta potential (between 13.57-40.29 mV) and the nanoparticle diameter of 99-138 nm. The conjugates of G4P and G4PFL at nanomolar concentrations were the most active, and the least active conjugate was G4F. The tested conjugates inhibited the proliferation of HaCaT and A549 cells; in glioma cells, cytotoxicity was associated mainly with cell damage (mitochondria and membrane transport). The toxicity of the conjugates was proportional to the number of drug residues attached, with the exception of G4L; its action was two- and eight-fold stronger against glioma and keratinocytes, respectively, than the equivalent of lapatinib alone. Unfortunately, non-cancer HaCaT cells were the most sensitive to the tested constructs, which forced a change in the approach to the use of ER and EGFR receptors as a goal in cancer therapy. In vivo studies on C. elegans have shown that all compounds, most notably G4PFL, may be potentially useful in anthelmintic therapy.

(Invited) Catalytic Growth of Width-Controlled Single Atomic Layer MoS2 Sub-10nm Nanoribbons

For the next generation materials for optoelectronics, quantum computing, communication and sensing, single atomic layer semiconducting nanoribbons offer additional degree of freedoms for engineering their properties. However, direct width-controlling synthesis of TMD nanoribbons, especially for the appealing width range below 30 nm, remains challenge. Therefore, developing facile methods for their direct and controllable synthesis is of central importance. We present a new growth method for single and double atomic layer of MoS2 nanoribbons with width down to sub-10 nm. Nanoribbons are grown via precipitation from the Ni-contained composite nanoparticles via vapor-liquid-solid mechanism in which the nanoparticle diameter also controls the width of nanoribbon. We also present preliminarily studies on width-dependent properties of the nanoribbons, which evidence their potential application in the quantum electronics, particularly as a single electron transistor and single photon emitter.

Spectrally selective nanoparticle-enhanced phase change materials: A study on data-driven optical/thermal properties and application of energy-saving glazing under different climatic conditions

The optical and thermal performances of energy-saving glazing require improvement to reduce peak thermal load and increase solar energy conversion and management efficiency. Herein, it is indispensable to develop novel composite materials that designate the ability to achieve multifunction by thermal load migration as well as radiation transmittance modulation. This study developed a nanoparticle-enhanced phase change material (NEPCM) with spectrally selective and phase change functions. A data-driven algorithm is first developed to evaluate the solar-weighted absorption fraction, integrated irradiance, and spectral irradiance for the considered nanoparticles. The base fluids, nanoparticle diameter, concentrations, and proportions are taken into account in the program, and adjustments to the properties of NEPCM can be easily made. The NEPCM properties exhibit a high blocking performance of near-infrared solar radiation by 30.9%, while keeping visible transmittance at 51.8% using ATO-Al2O3 NEPCM. Furthermore, the photothermal conversion performance of a NEPCM-filled energy-saving prototype window is explored, which yields a heat absorption rate of up to 0.27 °C/min when the solar irradiance is 800 W/m2. In addition, the energy consumption of transparent envelopes with NEPCM filler in a full-scale building is investigated. The results show that NEPCM regulated glazing potentially provides annual heating energy-saving from 5.1 to 41.7 kWh·m−2·year−1 in three representative climatic conditions in different global locations. Outcomes on the spectrally selective capabilities of the energy-saving window provide ideas for advancing the development of low-carbon transparent building envelopes.

Influence of different nanoparticles on the gas injection performance in EOR operation: Parametric and CFD simulation study

AbstractThis study aims to simulate the process of enhanced oil recovery (EOR) during gas injection along with nanoparticles and investigate the affecting parameters in a conventional carbonate oil reservoir. Ansys Fluent software with a suitable multiphase model was used to simulate natural gas injection with a nanoparticle into a core sample. The simulation model was validated with a laboratory test of natural gas injection. Then, to obtain the optimal values of each of the parameters affecting the process of EOR during the natural gas injection along with nanoparticles, the design of the experiment was carried out with the help of Qualitek‐4 software and the Taguchi method. Therefore, three factors, including nanoparticle type (clay, titanium oxide, and silica nanoparticles), nanoparticle diameter (2–50 nm), and the volume fraction of nanoparticles in the base fluid (0.5–5 vol.%), as influential factors on the EOR during natural gas injection along with nanoparticles were chosen. The results of the numerical study indicated that silica nanoparticles significantly affect EOR more than clay and titanium oxide nanoparticles. Moreover, the smaller the diameter of nanoparticles (close to 2 nm) and the more significant the volume fraction of nanoparticles in the base fluid (close to 5 vol.%), the higher the oil recovery factor will be. This phenomenon occurs due to changes in the density and viscosity of the base fluid and, consequently, improves the mobility ratio of the injected fluid. On the other hand, the tiny size of nanoparticles allows them to easily enter the pores of the reservoir rock without entrapping and producing oil from them. Eventually, the highest oil recovery factor (59%) was obtained using silica nanoparticles with a diameter of 2 nm and a volume fraction of 5 vol.% in natural gas injection.

Ultrasound-assisted synthesis of PDA nanoparticles with controllable size regulation

The particle size is of importance for polydopamine (PDA) nanoparticles in different applications. Therefore, the synthesis approaches of PDA nanoparticles with fine-controlled size are highly desirable. Here, a novel ultrasound-assisted strategy for size control preparation of PDA nanoparticles was reported. The incorporation of ultrasound facilitated the reaction kinetics of DA, which increased the nucleation rate of PDA nanoparticles, therefore yielding smaller PDA nanoparticles. The diameter of PDA nanoparticles can be regulated effectively from 162.8 to 666.7 nm through adjusting dopamine (DA) concentration from 1 to 4 mg/mL in ultrasound-assisted route. This work has enriched the controllable synthesis methods of PDA nanoparticles, which opens more room for size dependent applications of PDA nanoparticles.

Ac-Susceptibility Studies of the Energy Barrier to Magnetization Reversal in Frozen Magnetic Nanofluids of Different Concentrations

We used ac-susceptibility to measure the blocking temperature, TB, and energy barrier to the magnetization reversal, EB, of nanomagnetic fluids of different concentrations, c. We collected data on five samples synthesized by dispersing Fe3O4 nanoparticles of average diameter ⟨D⟩ = 8 nm in different volumes of carrier fluid (hexane). We found that TB increases with the increase in c, a behavior predicted by the Dormann–Bessais–Fiorani (DBF) theory. In addition, our observed TB vs. c dependence is excellently described by a power law TB = A∙cγ, with A = 64 K and γ = 0.056. Our data also show that a Néel–Brown activation law τT=τ0exp⁡EBkBT describes the superspin dynamics in the most diluted sample, whereas an additional energy barrier term, Ead, is needed at higher concentrations, according to the DBF model: τT=τrexp⁡EB+EadkBT. We found EB/kB = 366 K and additional energy barriers Ead/kB that increase linearly with the common logarithm of the volume concentration, from 138 K at c = 8.3 × 10−4% to 745 K at c = 4 × 10−2%. These results add to our understanding of the contributions by different factors to the superspin dynamics. In addition, the quantitative relations that we established between the TB, Ead, and c support the current efforts towards the rational design of functional nanomaterials.

Transcriptome analysis of some genes of Staphylococcus aureus exposed to alkylated, nano- and native chitosans

Chitosan, including native, N- alkyl (AlkCs), and nanoparticles chitosan (CsNPs), were prepared and characterized. Average size and hydrodynamic diameter of nanoparticles were determined at 126 nm and 240 nm with a polydispersity index (PDI) of 0.154 and zeta potential of 30 mV, respectively. Crystallinity index for Cs, AlkCs, and CsNPs was calculated as 57.85, 30.24, and 24.85, respectively. Minimum concentration of growth inhibition (125.78 µg/ml) and lethality (100 µg/ml) was observed for CsNPs (P < 0.05). CsNPs and AlkCs showed the highest diameter of the growth inhibition zone at 1250 μg/mL concentration, respectively (P < 0.05). Membrane permeability test, the highest absorption of ortho-nitrophenol was observed after 90 min with 0.11 nm. The most significant decrease in absorption in chitosan was observed at the end of 120 min. DAPI (4′,6-Diamidino-2-Phenylindole) staining test showed higher cell death of bacteria treated with AlkCs and CsNPs. Images obtained from atomic force microscopy (AFM) showed a change in the morphology of the treated cells compared to the spherical and clustered control cells. A significant increase in the expression of vraS, vraR, lytM, lrgA and lrgB genes was observed as a result of induction of S. aureus cell wall by Cs, AlkCs and CsNPs, d.

Averaging Strategy for Interpretable Machine Learning on Small Datasets to Understand Element Uptake after Seed Nanotreatment.

Understanding plant uptake and translocation of nanomaterials is crucial for ensuring the successful and sustainable applications of seed nanotreatment. Here, we collect a dataset with 280 instances from experiments for predicting the relative metal/metalloid concentration (RMC) in maize seedlings after seed priming by various metal and metalloid oxide nanoparticles. To obtain unbiased predictions and explanations on small datasets, we present an averaging strategy and add a dimension for interpretable machine learning. The findings in post-hoc interpretations of sophisticated LightGBM models demonstrate that solubility is highly correlated with model performance. Surface area, concentration, zeta potential, and hydrodynamic diameter of nanoparticles and seedling part and relative weight of plants are dominant factors affecting RMC, and their effects and interactions are explained. Furthermore, self-interpretable models using the RuleFit algorithm are established to successfully predict RMC only based on six important features identified by post-hoc explanations. We then develop a visualization tool called RuleGrid to depict feature effects and interactions in numerous generated rules. Consistent parameter-RMC relationships are obtained by different methods. This study offers a promising interpretable data-driven approach to expand the knowledge of nanoparticle fate in plants and may profoundly contribute to the safety-by-design of nanomaterials in agricultural and environmental applications.

Synthesis of carbon-encapsulated copper nanoparticles by the electrical explosion of wire method

The synthesis of carbon-encapsulated copper nanoparticles (Cu&C NPs) by the high-productive method of the electrical explosion of wire (EEW) is presented. Copper wire was evaporated by high-energy electrical current pulses. Evaporation of Cu and the consequent condensation of spherical nanoparticles took place in argon with the controlled addition of butane, which provided encapsulation of copper nanoparticles in carbon shells. Carbon was deposited in the form of several graphite layers, which completely covered the surface. The encapsulation diminished the agglomeration of carbon-encapsulated copper nanoparticles (Cu@C NPs) during their condensation and substantially diminished their average diameter. Upon the deposition of about 4 % of carbon, the average diameter of nanoparticles decreased more than three-fold – from 130 to about 40 nm. Simultaneously, the specific surface area of Cu@C NPs increased from 7 to 35 m2/g. The deposited dense and gas tight carbon shells protected the surface of particles from oxidation. It prevented the self-ignition of as-synthesized nanoparticles at the exposure to ambient air and provided stability to oxidation during long-term storage as well.

Effect of Nanoparticle Diameter in Maxwell Nanofluid Flow with Thermophoretic Particle Deposition

The time-dependent Maxwell nanofluid flow with thermophoretic particle deposition is examined in this study by considering the solid–liquid interfacial layer and nanoparticle diameter. The governing partial differential equations are reduced to ordinary differential equations using suitable similarity transformations. Later, these reduced equations are solved using Runge–Kutta–Fehlberg’s fourth and fifth-order method via a shooting approach. An artificial neural network serves as a surrogate model, making quick and precise predictions about the behaviour of nanofluid flow for various input parameters. The impact of dimensionless parameters on flow, heat, and mass transport is determined via graphs. The results reveal that the velocity profile drops with an upsurge in unsteadiness parameter values and Deborah number values. The rise in space and temperature-dependent heat source/sink parameters value increases the temperature. The concentration profile decreases as the thermophoretic parameter upsurges. Finally, the method’s correctness and stability are confirmed by the fact that the maximum number of values is near the zero-line error. The zero error is attained near the values 2.68×10−6, 2.14×10−9, and 8.5×10−7 for the velocity, thermal, and concentration profiles, respectively.

Nanofluid turbulent flow in parabolic trough collector: Insulator roof, acentric absorber tube and SiC nanoparticles effects

The key purpose of the current study is to design a parabolic trough collector (PTC) having insulator roof and an acentric absorber tube, with nanofluid using single-phase and two-phase mixture models (TPM and SPM). The effects of employing the SPM and TPM on the fluid field and heat transfer of nanofluid (SiC nanoparticles (16–90 nm) and volume fraction (0–4%) to the water and EG-water) in the absorber tube is studied. Results of present investigation shown that for both proposed (novel) and conventional PTC arrangements, the pressure drop (3%), Nusselt number (5%), friction factor (3%), energy efficiency (3%), and performance evaluation criteria (PEC) (3%) employing the TPM are greater than that of SPM. In addition, it is shown that employing the novel PTC presents greater Nusselt number (25%), energy efficiency (30%), and PEC (50%). Temperature field inside the absorber tube and heat transfer fluid zone employing the TPM are greater than that of SPM. Maximum PEC for SiC/EG-water and EG-water nanofluid are 1.67 and 1.70, respectively, for sinusoidal-wavy minichannel having a nanoparticle volume fraction of 4%, nanoparticles diameter of 90 nm, and Reynolds number of 15,001.3. Furthermore, EG-water as base fluid with a nanoparticle diameter of 90 nm presents greater energy efficiency than water.

Synthesis of silicate clay minerals-based novel Mt/YF3:Eu3+ nanocomposites for regulated luminescent intensity-quantum yield-fluorescence lifetime

Rare earth luminescent materials have broad application prospects in the fields of white light LED lighting, flat panel display, biological imaging and so on. Here, we developed a novel silicate clay minerals-based montmorillonite nanosheet(Mt)/YF3:Eu3+ nanocomposites with strong luminescence performance. Mt carrier plays a three role: (1) reducing the size and improving dispersion of YF3: Eu3+ nanoparticles by surface effect; (2) narrowing down the band gap and increasing Urbach tail energy by interface effect; (3) reducing the shielding of the hole-electron Coulomb interactions while improving the exciton binding energy of YF3:Eu3+, thus improving the radiative recombination by dielectric effect. Therefore, orthogonal phase YF3: Eu3+ nanoparticles (diameter 20∼140 nm) binding to the surface of Mt via chemical bond interactions. The combination of Mt and YF3:Eu3+ not only enhanced luminescent intensity (about 2 times) but also improved the quantum yield (0.14% to 0.4%) and fluorescence lifetime (0.338 ns to 0.405 ns) of YF3:Eu3+ nanoparticles at 595 nm. In addition, the combination of Mt and YF3:Eu3+ give luminescent properties to Mt thereby improving the utilization rate of Mt and YF3: Eu3+ nanoparticles. It was found that the research supplies an insight on the development of new type luminescent materials, and hopefully it could promote them application in many fields.

Development of lipid nanoparticles with nystatin for an antifungal action

Fungal diseases currently affect about a quarter of the population worldwide. Fungi infections caused by Candida albicans have been described as a significant concern to public health. The spectrum of clinical diseases caused by this fungi species range between vulvovaginal candidiasis, oral candidiasis, candidemia and mucositis. The emergence of resistance mechanisms towards antifungal therapy greatly hampers successful management of illness and patient outcome. Nystatin, an antifungal drug, is categorized as a class IV of Biopharmaceutical Classification System, presenting low aqueous solubility and low intestinal permeability. Nowadays, the emerging platform of nanotechnology and lipid nanoparticles, notably solid lipid nanoparticles (SLN), has been subject to growing attention over recent past, owing to the promising properties of vectorization among a substantial variety of pharmaceutical drugs. Due to its hydrophobic proprieties, nystatin was encapsulated in SLN. Thus aiming to understand the relationship between the use of nanosystems and the improvement of the therapeutic effect. The aim of this work was to formulate SLN with nystatin by different methods (high speed homogenization and ultrasonication) with optimization of several parameters and formulation of 2 gels (one of them containing nanoparticles).&#x0D; Initially, 3 lipids were used: Compritol® 888 ATO, cetyl palmitate and Precirol® ATO 5 and, after the study of several parameters (size, encapsulation efficiency (EE) and polymorphic behaviour of the lipids), Precirol® ATO 5 was chosen as the lipid with the most satisfactory results. The results of the present work showed that the assay method of nystatin was linear, specific and presented repeatability. The average diameter of empty nanoparticles (NPs) and with drug (Precirol-NYS NPs) was, respectively, 306 nm and 260 nm and an EE of 67.8%. Regarding stability, SLN with drug proved to be more stable than SLN without drug. The polymer used for formulation of gels was the polymer commonly known by the trade name Carbopol® 940. The yield of 0.5% Carbopol® gel preparations and 0.5% Carbopol® gel + 10% Precirol-NYS NPs were 87.2% and 91.39%, respectively.

Entropy generation of Al2O3/water nanofluid in corrugated channels

The flow of nanofluids in a corrugated channel has been shown to have a significant impact on heat transfer performance, and has therefore become an important area of research. The ob- jective of this paper is to understand the thermal behavior of Al2O3/water nanofluid in a sinu-soidal and square channel and to identify ways to optimize heat transfer performance in such configurations. For this purpose, a numerical simulation was conducted using ANSYS-Fluent software 16.0 on entropy generation and thermo-hydraulic performance of a wavy channel with the two corrugation profiles (sinusoidal and square). The analyses were carried out under laminar forced convection flow conditions with constant heat flux boundary conditions on the walls. The influence of various parameters, such as particle concentration (0–5%), particle di-ameter (10nm , 40nm and 60nm), and Reynolds number (200 &lt; Re &lt; 800) on the heat transfer, thermal, and frictional entropy generation, and Bejan number was analyzed. Moreover, the distribution of streamlines and static temperature contours has been presented and discussed, and a correlation equation for the average Nusselt number based on the numerical results is presented. One of the most significant results obtained is that the inclusion of nanoparticles (5% volume fraction) in the base fluid yielded remarkable results, including up to 41.92% and 7.03% increase in average Nusselt number for sinusoidal and square channels, respectively. The sinusoidal channel exhibited the highest thermo-hydraulic performance at Re= 800 and φ= 5%, approximately THP= 1.6. In addition, the increase of nanoparticle concentration from 0% to 5% at Re= 800 and dnp= 10nm, diminishes the total entropy generation by 28.39 % and 22.12 % for sinusoidal and square channels, respectively, but when the nanoparticle diameter decreases from 60nm to 10nm at ϕ= 5% and Re= 800, the total entropy generation in the sinusoidal channel decreases by 34.85%, whereas in the square channel, it decreases by 20.05%. Therefore, rather than using a square channel, it is preferable and beneficial to use small values of nanoparticle diameter and large values for each of ϕ and Re in the sinusoidal wavy channel. Overall, the study of nanofluid flow in a wavy channel can provide valuable insights into the behavior of nanofluids and their potential applications in a variety of fields, including manufacturing, energy produc-tion, mining, agriculture, and environmental engineering.

Optimization of Hydrothermal Synthesis of Dysprosium Oxide Nanoparticles- Attached-Polyethyleneglycol Template Using Response Surface Methodology- Box-Behnken

Dysprosium oxide nanoparticles (Dy2O3-nanoparticles) have been extensively used in many different fields of technologies. In addition, with a proper synthesis modification, Dy2O3-nanoparticles are promising materials not only for industry purposes, but also for biomedical applications, for instance, through polyethyleneglycol (PEG) attachment as a template on nanoparticles. This study focuses on the optimization of hydrothermal synthesis of Dy2O3-nanoparticles using Response Surface Methodology – Box-Behnken experimental design (RSM-BBD). The influences of the volume and concentration of PEG-template to the size diameter of nanoparticles were also studied. The crystal structure and surface morphology Dy2O3-nanoparticles with PEG-template modification were characterized using Tabletop Scanning Electron Microscopy (TSEM) coupled with Energy Dispersive X-Rays (SEM-EDX) and X-Rays Diffraction (XRD). Dy2O3-nanoparticles were prepared by using hydrothermal synthesis method with PEG-template attachment on the nanoparticles. PEG as a template will create the uniform shapes and prevent the agglomeration of the nanoparticles. For further biomedical applications, it also helps to enhance the biocompatibility of nanoparticles. The optimization of influence parameters on the hydrothermal synthesis of Dy2O3-nanoparticles, (e.g. mass ratio precursor (PEG and Dy2O3), temperature, and time) were investigated using RSM-BBD. The optimum conditions were 15 g PEG and 0.45 g Dy2O3 at 200°C for 7 h resulting in the highest amount of Dy2O3-nanoparticles products. SEM image results show spherical and nanowires shapes of Dy2O3-nanoparticles produced with the average size diameter of 10.1 nm as the smallest size of nanoparticles. In addition, XRD-patterns indicates the typical cubic structure of Dy2O3-nanoparticles with the estimation crystal size of 45.47 nm.

Using pomegranate peel extract green synthesize of AG nanoparticles: characterization and antibacterial activity

In this research, the eco-friendly biogenesis of silver nanoparticles from 2 mM AgNO3 using the extraction of pomegranate peel (EPP) as the agent of reduction was explored. Analysis of the Fourier transform infrared spectrum (FT-IR), UV-visible spectrum, and scanning electron microscopy (SEM) were used to characterize Ag nanoparticles. At 425 nm, UV-visible spectra show a significant resonance on the surface of silver nanoparticles (AgNPs). A spectrum investigation using FTIR spectroscopy revealed that EPP operated as a reduction agent. SEM analysis reveals nanoparticles with average particle sizes ranging between 30 and 50 nm. AgNPs' antibacterial activity was also tested against Staphylococcus aureus. X-ray diffractometer (XRD), using Scherrer's equation and the refraction peak in the XRD pattern, the average particle diameter of the silver nanoparticles was determined to be 80. The silver nanoparticles formed in the brown-colored stable samples according to SEM analysis, and well-dispersed nanoparticles could be seen in the silver nitrate-treated samples. Ag nanoparticles produced by pomegranate peel extract show the maximum antibacterial activity against S. aureus (0.1, 0.2, 0.3 and 0.4 mol). This technique produces Ag NPs with effective antibacterial action against harmful microorganisms. One of these is silver nanoparticles, which have a substantial influence on nanotechnology and the field of nanomedicine.

Control of Intermolecular Interactions toward the Production of Free-Standing Interfacial Polydopamine Films.

Aggregation of the polydopamine (PDA) molecular building blocks at the air/water interface leads to obtaining large surface nanometric-thin films. This mechanism follows two possible pathways, namely, covalent or non-covalent self-assembly, which result in a different degree of structure order and, consequently, different structural properties. Control of this mechanism could be vital for applications that require true self-support PDA free-standing films, for example, electrochemical sensing or membrane technology. Here, we are considering the impact of boric acid (BA) and Cu2+ ions on the mentioned mechanism exclusively for the free-standing films from the air/water interface. We have employed and refined our own spectroscopic reflectometry method to achieve an exceptionally high real-time control over the thickness growth. It turned out that BA and Cu2+ ions significantly impact the film growth process. Reduction of the nanoparticles size and their number was examined via UV-vis spectroscopy and transmission electron microscopy, showing a colossal reduction in the mean diameter of nanoparticles in the case of BA and a moderate reduction in the case of Cu2+. This modification is leading to significant enhancement of the process efficiency through moderation of the topological properties of the films, as revealed by atomic force microscopy. Next, applying infrared, Raman, and X-ray photoelectron spectroscopy, we presented small amounts of metal (B or Cu) in the final structure of PDA and simultaneously their vital role in the oxidation mechanism and cross-linking through covalent or non-covalent bonds. Therefore, we revealed the possibility of synthesizing films via the expected self-assembly mechanism which has hitherto been out of control. Moreover, modification of mechanical properties toward exceptionally elastic films through the BA-assisted synthesis pathway was shown by achieving Young's modulus value up to 24.1 ± 5.6 and 18.3 ± 6.4 GPa, using nanoindentation and Brillouin light scattering, respectively.

Green Synthesis of ZNO Nanoparticles using Aloe Vera Leaves Extract

Characterization of the created ZnO nanoparticles using the following techniques: Fouriesr Transform Infra RedSpectrum (FTIR), Scanning Electron Microscopic (SEM), Atomic Force Microscope (AFM). Atomic Force Microscopy (AFM) was employed to describe the surface morphology, particle size in nanoscale, dimeter and roughness of the surface for zinc nanoparticles prepared from plant extraction. The morphology images of pure plant extract and biosynthesised zinc nanoparticles that explains the 3D image of the surface morphology.The particle size in nanoscale of pure plant extraction was 87.22nm and zinc nanoparticles were found to have a particle size of 36.42nm. height cumulation distributions that determine the volume percentage of plant extract's grain size particles and biosynthesised zinc nanoparticles, recording 50.269 nm average hight of plant extraction and 21.515 nm average height of synthesized zinc nanoparticles, displays the Granularity Cumulation Distribution, which calculates the volume percentage of the diameter of plant extract and synthetic zinc nanoparticles. The average diameter of plant extract was 133.77 nm, whereas the average diameter of synthetic zinc nanoparticles made by plants extract was 52.84 nm. The roughness of the surface RMS (Root mean square) of pure plant extraction and the synthesized zinc nanoparticles that that RMS of plant extract was 13.2nm, while the RMS of synthesized zinc nanoparticles was 5.21nm. Scanning electron microscope (SEM) analysis explained the morphology of the surface and shape formation of plant extract and synthesized zinc nanoparticles , that exhibits the micrograph of plant extraction and synthesized zinc nanoparticles and shows that the zinc nanoparticles were formed as nanosheets and hierarchical shape in huge quantities and different lengths nanosheets. Scanning electron microscopy (SEM) element mapping at the microstructural level shows the distribution and quantities of zinc nanoparticles elements prepared from the plant extract and oxygen.It is noticed that the high amount of zinc prepared. FTIR findings for the crude The appearance of a broad peak at (2320.47 cm-1) in an Aleo vera extract is due to the stretching O-H groups of phenolic groups and carbohydrate monomers.

Optical gratings fabricated using the capillary-assisted self-assembly of nanoparticles on a flexible substrate.

We demonstrate a cost-effective and high-throughput fabrication technique to deposit colloidal nanoparticles on a patterned polymer substrate using a capillary-assisted self-assembly method over a large area. In particular, we fabricate optical gratings using gold nanoparticles and a polymer substrate. We show the versatility of the technique over different nanoparticle diameters and grating periodicities. Through both experiments and simulations, we show enhanced transmission in the first-order diffraction of the gold-polymer grating as compared to the air-polymer grating. Our fabrication technique also enables the transfer of the nanoparticle pattern from the polymer substrate to any desired surface. Here we demonstrate the transfer of the nanoparticle grating structure to the tip of optical fibers.