Arrays of planar symmetric gold quadrumers consisting of a central nano-disc surrounded by three similar nano-discs belonging to the D(3h) point group were designed and fabricated. Since the geometrical configuration of quadrumers is the same as planar trigonal molecules, nano-discs can play the roles of artificial atoms to study the coupling trends among them. The plasmonic properties of the n...

paper chromatography is an analytical technique for separating and identifying mixtures of materials. it is a useful technique since it is relatively quick, and requires small quantities of the material. by emergence of nanotechnology, paper chromatography has found many applications in biology and biotechnology. in this study, we employed gold and silver nanoparticles to detect protein bands a...

Gold exhibits catalytic activity when it is in the form of fine particles having a size of less than 10 nm and is tightly supported on specific metal oxides such as TiO2, etc [1]. To reveal its mechanism, dynamic observation of the sample structures during the reaction by the transmission electron microscope (TEM) is quite essential. “Environmental-cell (E-cell) TEM” technique [2], which enable...

Density functional theory is used to find incremental fragmentation energy, overall dissociation energy, and average monomer fragmentation energy of cyclic gold(I) thiolate clusters and anionic chain structures of gold(I) and silver(I) thiolate clusters as a measure of the relative stability of these systems. Two different functionals, BP86 and PBE, and two different basis sets, TZP and QZ4P, a...

Disturbance in water relations is the major causes of vase life reduction and senescence in cut flowers This problem is mainly due to microorganism proliferation in the vase solution which leads to vascular occlusion and reduction in solution uptake by cut flowers. Therefore a comprehensive study was conducted to evaluate the biocidal effect of nano silver particles (NSP) and compare it with so...

Gold-silver alloy nanoparticles with varying mole fractions are prepared in aqueous solution by the coreduction of chlorauric acid HAuCl4 and silver nitrate AgNO3 with sodium citrate. As the optical absorption spectra of their solutions show only one plasmon absorption it is concluded that mixing of gold and silver leads to a homogeneous formation of alloy nanoparticles. The maximum of the plas...

Excitation of localized and delocalized surface plasmon resonances can be used for turning excellent reflectors of visible light, such as gold and silver, into efficient absorbers, whose wavelength, polarization or angular bandwidths are however necessarily limited owing to the resonant nature of surface plasmon excitations involved. Nonresonant absorption has so far been achieved by using comb...

Nanotechnology is new form of technology which has produced a great development in variousfields. Nanoparticles are of the great scientific interest as they are effectively a bridge between bulk material and atomic & molecular structures. Nanoparticles are the particle that have size 1 to 100 nm and possess due to large surface area to volume ratio & smaller size. Different types of nanom...