Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Materials Chemistry

Selected Works

2012

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Aging Of A Thermoelectric Module: Visualization Of Elemental Analysis, Stacie M. Dahl, Bernice E. Mills Aug 2012

Aging Of A Thermoelectric Module: Visualization Of Elemental Analysis, Stacie M. Dahl, Bernice E. Mills

Stacie M Dahl

Visualization of elemental composition is done to compare the surfaces of an aged thermoelectric module (TM) to an unaged one. The two modules’ exteriors are also compared to their interiors. Highlights of the analysis are presented here.

Go to article

A Simple Biogenic Route To Rapid Synthesis Of Au@Tio2 Nanocomposites By Electrochemically Active Biofilms, Mohammad Mansoob Khan Dr, M. H. Cho Jul 2012

A Simple Biogenic Route To Rapid Synthesis Of Au@Tio2 Nanocomposites By Electrochemically Active Biofilms, Mohammad Mansoob Khan Dr, M. H. Cho

Dr. Mohammad Mansoob Khan

Deposition of gold on titanium dioxide (TiO2) nanoparticles is highly beneficial for maximizing the efficiency of many photocatalytic reactions. In this study, we have reported for the first time the use of an electrochemically active biofilm (EAB) for the synthesis of Au@TiO2 nanocomposite with sodium acetate as the electron donor. The EAB acts as an electron generator for the reduction of gold ions on the surface of TiO2 nanoparticles. It was observed that the TiO2 plays not only as a support for the gold nanoparticles but also as a storage of electrons produced by the EAB within the particles. These …

Go to article

The Effect Of Frictional And Adhesion Forces Attributed To Slurry Particles On The Surface Quality Of Polished Copper, Yi-Koan Hong, Ja-Hyung Han, Tae-Gon Kim, Jin-Goo Park, Ahmed Busnaina Apr 2012

The Effect Of Frictional And Adhesion Forces Attributed To Slurry Particles On The Surface Quality Of Polished Copper, Yi-Koan Hong, Ja-Hyung Han, Tae-Gon Kim, Jin-Goo Park, Ahmed Busnaina

Jin-Goo Park

The effect of frictional and adhesion forces attributed to slurry particles on the quality of copper surfaces was experimentally investigated during copper chemical mechanical planarization process. The highest frictional force of 9 Kgf and adhesion force of 5.83 nN were observed in a deionized water-based alumina slurry. On the other hand, the smallest frictional force of 4 Kgf and adhesion force of 0.38 nN were measured in an alumina slurry containing citric acid. However, frictional (6 Kgf) and adhesion (1 nN) forces of silica particles in the slurry were not significantly changed regardless of the addition of citric acid. These …

Go to article

Synthesis, Characterization And Nonlinear Optical Properties Of Silver/Pva Nanocomposites, Mahdi Shahmiri Jan 2012

Synthesis, Characterization And Nonlinear Optical Properties Of Silver/Pva Nanocomposites, Mahdi Shahmiri

mahdi shahmiri

Silver/polyvinyl alcohol (PVA) nanocomposites are prepared via quick precipitation method, using hydrazine as a reducing agent. Preparing of silver/PVA nanocomposites by this method is done for the first time. The samples are characterized by Uv-Visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM). Nonlinear optical properties are carried out by Z-scan technique using a blue CW laser beam operated at wavelength 405 nm. It is shown that the synthesized samples have negative nonlinear refractive index and the magnitude is in the order of 10􀀀8. The nonlinear refractive index increases as amount of reducing agent increases.

Go to article

C60 Oxide As A Key Component Of Aqueous C60 Colloidal Suspensions, Befrika Murdianti, Joshua Damron, Martha Hilburn, Randall Maples, Rangika Hikkaduwa Koralege, Sathish Kuriyavar, Kevin Ausman Dec 2011

C60 Oxide As A Key Component Of Aqueous C60 Colloidal Suspensions, Befrika Murdianti, Joshua Damron, Martha Hilburn, Randall Maples, Rangika Hikkaduwa Koralege, Sathish Kuriyavar, Kevin Ausman

Kevin D. Ausman

Stable aqueous fullerene colloidal suspensions (nC60) are demonstrated to rely on the [6,6]-closed epoxide derivative of the fullerene (C60O) for stability. This derivative is present, though often unrecognized, in small quantities in nearly all C60 starting materials due to a reaction with air. The low-yield formation of nC60 from organic solvent solutions results from a preferential partitioning and thus enrichment of C60O in the colloidal particles. This partitioning is significantly retarded in the nC60 synthesis method that does not involve organic solvent solutions: long-term stirring in water. Instead, this method relies on trace levels of ozone in the ambient atmosphere …

Go to article

Fluorescein-Polyethyleneimine Coated Gadolinium Oxide Nanoparticles As T1 Magnetic Resonance Imaging (Mri)–Cell Labeling (Cl) Dual Agents, Wenlong Xu, Ja Young Park, Krishna Kattel, Md Wasi Ahmad, Badrul Alam Bony, Woo Choul Heo, Seonguk Jin, Jang Woo Park, Yongmin Chang, Tae Jeong Kim, Ji Ae Park, Ji Yeon Do, Kwon Seok Chae, Gang Ho Lee Dec 2011

Fluorescein-Polyethyleneimine Coated Gadolinium Oxide Nanoparticles As T1 Magnetic Resonance Imaging (Mri)–Cell Labeling (Cl) Dual Agents, Wenlong Xu, Ja Young Park, Krishna Kattel, Md Wasi Ahmad, Badrul Alam Bony, Woo Choul Heo, Seonguk Jin, Jang Woo Park, Yongmin Chang, Tae Jeong Kim, Ji Ae Park, Ji Yeon Do, Kwon Seok Chae, Gang Ho Lee

Dr. Mohammad Wasi Ahmad (Md Wasi Ahmad)

We report the synthesis, characterization and application of highly water-soluble fluoresceinpolyethyleneimine (PEI) coated gadolinium oxide (Gd2O3) nanoparticles to magnetic resonance imaging (MRI) and cell labeling (CL). The average particle diameter and average hydrodynamic diameter were estimated to be 3.92 and 7.5 nm, respectively. Fluorescein-PEI was prepared from EDC/NHS coupling method. The surface coating was characterized by the FT-IR absorption spectrum and the surface coating amount was estimated to be 22.42 wt% from a TGA analysis, corresponding to 0.65 nm22 grafting density. The fluorescein-PEI coated gadolinium oxide nanoparticles showed r1 and r2 of 6.76 and 20.27 s21mM21, respectively, and a strong …

Go to article