Current Nanoscience - Volume 4, Issue 2, 2008

Nanomaterials are typically considered as solid physical structures that comprise grain boundaries at the resolution of less than 100 nanometers, whereby nanotechnologies are depicted as dealing with the design of various applications based on employing the former. Some of the essential features of nanomaterials and the scientific approaches to their investigation are discussed in the course of this work. The real reason f Read More

Polyacrylonitrile (PAN)-based carbon nanofibers (CNFs) were prepared via the electrospinning process. Silver (Ag) modifications of these CNFs were carried out using in-situ Ag reaction as well as Ag coating methods. Ag modified CNFs from both methods yielded higher electrical conductivity than the neat CNFs due to the synergetic effect from the Ag nanoparticles. The effects of fiber diameter, fiber aspect ratio and the interconn Read More

Silver nanoparticles have been prepared under microwave irradiation from a solution of silver nitrate. Different morphologies of silver colloids with charming colors could be obtained using two different reducing agents namely sodium citrate (SC) and N1, N2- diphenylbenzamidine (DPBA) or simply amidine. The structures of silver colloids were determined by TEM. UV-Vis spectroscopy was used to follow the reaction process a Read More

We report extracellular mycosynthesis of silver nanoparticles by Fusarium acuminatum Ell. and Ev. (USM-3793) isolated from infected ginger (Zingiber officinale). An aqueous silver nitrate solution was reduced to metallic silver when exposed to F. acuminatum cell extract leading to the appearance of a brown color within 15-20 minutes. The color is due to the formation of silver nanoparticles and the excitation of surface Read More

This paper presents a hydrothermal method for the synthesis and stabilization of gold nanodisks with a preferential growth direction along the (111) plane inside environmentally-besign sodium alginate sol by a one-step strategy without additional reducing agent. This is carried out by transferring a sodium alginate/HAuCl4 aqueous solution into a stainless steel autoclave with a Teflon liner and heating in an oven at 100°C for 30 h. Fi Read More

TiO2 nanocrystalline powders were synthesized in the anatase phase by a modified sol-gel method. The effect of calcination temperature was also studied; XRD pattern of the sample dried at 100°C showed a significant amount of amorphous content, and crystallinity enhanced by increasing the calcination temperature. AFM images demonstrate submicron agglomerate particles. FT-IR spectra represent the formation of Ti-O-Ti b Read More

In order to obtain oriented nanostructured materials for nanoelectronic/microelectronic applications, a simple sol-gel method to form ZnO nano-structures under different heat treatment conditions was investigated. The results indicated that ZnO nanobelts could be obtained by the presence of small amount of triethanolamine, which acted as soft template. The orientation degree of the ZnO nanobelts was improved significan Read More

The Wiener index of a graph G is defined as W(G) =1/2&b.Sigma;{x,y}⊆V(G)d(x,y), where V(G) is the set of all vertices of G and for x,y &b.epsis; V(G), d(x,y) denotes the length of a minimal path between x and y. In this paper an algorithm for computing the Wiener matrix of a TUC4C8(R) nanotube T = T[p,q] is given. Using this matrix, an exact expression is given, for the Wiener index of T.

Water condensation is shown to have a major influence on electric charge transport and nanostructure formation in polymer-, and semiconductor-thin-film surfaces in the proximity of a biased Atomic Force Microscope (AFM) tip. The water forms a meniscus bridge between the AFM tip and the surface to form a three-component system comprised of the AFM tip, water meniscus, and the surface. The associated electric field in t Read More

A central composite experimental design was applied to investigate the effect of five preparative variables on the size and cisplatin encapsulation efficiency of poly(lactide-co-glycolide)-methoxy poly(ethylene glycol) (PLGA-mPEG) nanoparticles. The nanoparticles were prepared by a nano-precipitation process and were characterized with regard to their morphology by scanning electron microscopy, their size by photon cor Read More

An extension of the classical thermodynamics to nanometer scale has been conducted to elucidate information regarding size dependence of phase transition functions and binary phase diagrams. The theoretical basis of the extension is Lindemann's criterion for solid melting, Mott's expression for vibrational melting entropy, and Shi's model for size dependent melting temperature. These models are combined into a Read More

Self- assembly of biological molecules forms the basic principle in the formation of complex biological structures. Numerous proteins and peptides have been emerging as nanobiomaterials due to their ability to self-assemble into nanoscale structures like nanotubes, nanovesicles, helical ribbons and three dimensional fibrous scaffolds. This mini review discusses the basic principle underlying molecular self-assembly of proteins an Read More

Molecular organization has an important influence on the performance of organic materials, i.e. solar cells, light emitting diodes or sensors. 4,4'-Dimethyl-2,2'-bipyridines have been identified as a promising candidate for such applications. Therefore, high resolution STM investigations at the solid-liquid interface have been conducted, to study the intermolecular interaction of the bipyridine moieties. The results provide inside i Read More

The aim of this paper is to develop highly magnetized, biodegradable and biocompatible, polymeric nanoparticles for drug delivery in cell therapy. Alginate magnetic nanoparticles are realized by an emulsion/reticulation technique, after the dispersion of magnetite in an alginate solution. Such nanoparticles are characterized in terms of external morphology (FIB imaging), microstructure (TEM imaging), size distribution, zeta pot Read More

The use of three dimensional scaffolds in tissue engineering is well reported, as is the exploitation of nanotopography to influence cell response. To date, due to fabrication limitations, the combination of these two has experienced limited research. This paper reports on the use of polymer demixing, a rapid and cheap nanofabrication method, to create a defined nanotopography in 0.5mm diameter nylon tubes. Results indic Read More