surface-enhanced raman spectroscopy (sers) is a promising tool in the analytical science because it provides good selectivity and sensitivity without the labeling process required by fluorescence detection. this technique consists of locating the target analyte on nanometer range of roughed au-nanoparticles. the presence of the metal nanoparticles provides a tremendous enhancement to the result...

in this report, magnetic iron oxide nanoparticles were synthesized via coprecipitation of fe2+ and fe3+ with ammonium hydroxide, and the surface of synthesized nanoparticles was organically functionalized by commercially available amine coupling agent namely, 3-aminopropyl trimethoxysilane (apts) by using well-known sol–gel method. further reaction of the synthesized fe3o4@apts core-shell magne...

We synthesized Bi/Bi2O3 heterojunction nanoparticles at various substrate temperatures using the pulsed laser deposition (PLD) technique with a pulsed Nd:YAG laser. The Bi/Bi2O3 heterojunction nanoparticles consisted of Bi nanoparticles and Bi2O3 surface layers. The average diameter of the Bi nanoparticles and the thickness of the Bi2O3 surface layer are linearly proportional to the substrate t...

In this study adsorption of Cr(VI) from aqueous solution by Fe3O4 nanoparticles was investigated. Desorption process and recovery of nanoparticles using different solutions were then carried out, and it was observed that NaOH (0.5M) can remove 90% of adsorbed chromium ions. Following the completion of adsorption/ desorption cycles, it was determined that nanoparticles have still had a high abil...

The objective of this study is to evaluate the effect of hydroxyapatite (HAP) nanoparticles with different surface charges on the cellular uptake behavior and in vitro cell viability and proliferation of MC3T3-E1 cell lines (osteoblast). The nanoparticles' surface charge was varied by surface modification with two carboxylic acids: 12-aminododecanoic acid (positive) and dodecanedioic acid (nega...

this paper provides an overview of how the surface properties of ferromagnetic nanoparticles dispersed in fluids is modified by natural and biocompatible polymers. among common magnetic nanoparticles, magnetite (fe3o4) and maghemite (g-fe203) are popular candidates because of their biocompatibility. natural polymeric coating materials are the most commonly used biocompatible magnetic nanopartic...

Due to the importance of nanoparticles stability in industrial applications, in this research, stability of laponite nanoparticles dispersions containing different concentrations of sodium sulfonated polyacrylamide (SPA) was investigated in electrolyte media for oil reservoirs applications. In this regard, effect of parameters such as polymer concentration, temperature, and ionic strength were ...

Metallic nanoparticles can exhibit very large optical extinction in the visible spectrum due to localized surface plasmon resonance. Spherical plasmonic nanoparticles have been the subject of numerous studies in recent years due to the fact that the scattering response of spheres can be analytically evaluated using Mie theory. However a major disadvantage of metallic spherical nanoparticles is ...

The adsorption of silica nanoparticles onto representative mineral surfaces and at the decane/water interface was studied. The effects of particle size (the mean diameters from 5 to 75 nm), concentration and surface type on the adsorption were studied in detail. Silica nanoparticles with four different surfaces [unmodified, surface modified with anionic (sulfonate), cationic (quaternary ammoniu...

Plasmonic nanoparticles located on the illuminated surface of a solar cell can perform the function of an antireflection layer, as well as a scattering layer, facilitating light-trapping. Al nanoparticles have recently been proposed to aid photocurrent enhancements in GaAs photodiodes in the wavelength region of 400-900 nm by mitigating any parasitic absorption losses. Because this spectral reg...