This paper is aimed at selectivity investigation of gas sensors, based on chemically modified nanocrystalline tin dioxide in the detection of CO and ammonia mixtures in air. Sol-gel prepared tin dioxide was modified by palladium and ruthenium oxides clusters via an impregnation technique. Sensing behavior to CO, NH3 and their mixtures in air was studied by in situ resistance measurements. Using...

A~ exact sol~tion in the Faxen approximation is given for the Lamm eq uation in which the sedi. mentatIOn coefficient IS related to concentration as s = ~(l kc). It is s hown that the solution in this case can be expressed in terms of the so lution to the linear case (k =O) with a modified argument. The boundary sharpenI ng phenomenon expresses itself very clearly in the solution presented he re.

It is of great significance for dynamic monitoring of foods in storage or during the transportation process through on-line detecting trimethylamine (TMA). Here, TMA were sensitively detected by Au-modified hierarchical porous single-crystalline ZnO nanosheets (HPSCZNs)-based sensors. The HPSCZNs were synthesized through a one-pot wet-chemical method followed by an annealing treatment. Polyethy...

The pyrolysis of transition metal carboxylates into organically modified silica glass-ZrO2 hybrid sol-gel films yields composite materials containing cobalt oxide nanoparticles in various proportions. The particles have sizes ranging from 5 to 10 nm, and they are homogeneously dispersed in the final materials. A reaction temperature near 250°C results in translucent films that have good mechani...

In this article we introduce and compare three techniques for low-cost and rapid bonding of stereolithographically structured epoxy components to polydimethylsiloxane (PDMS). In short, we first create a polysiloxane layer on the epoxy surface via silane surface coupling and polymerization. Afterwards, the modified epoxy surface can be bonded to a PDMS component at room temperature using a handh...

Wetting front instability (fingered flow) accelerates solute transport through the unsaturated zone to the groundwater table. Whether fingers widen or dissipate close to the groundwater is unclear. Water flow in a two-dimensional artificial capillary fringe below a dry layer exhibiting fingered flow was investigated. The flow diverged strongly in the wet soil, suggesting that fingers dissipate....

the austenitic stainless steel (ss) has been used as a material for  building  ultra  high  vacuum  (uhv)  chamber.  recently significant  efforts  have  been  concerned  a  comparing  the standard  cleaned  for  ultra  high  vacuum,  passivity  stainless. in  this work austenitic  nanocomposites were  synthesize by sol-  gel method. the morphologies  and  topographies  of  the samples  have  b...

A modified sol-gel process has been found to significantly improve the photocatalytic activity of TiO2 nanoparticle in the process of solar hydrogen production. The surface of TiO2 nanoparticles were modified by the optimization of solvent of titanium precursor (acetic acid and/or ethanol) in the sol-gel method. A multi technique approach (SEM, XRD, FTIR, UV-DRS and TGA) was used to characteriz...

In this study, Ti/SnO2-Sb2Ox-TiO2 electrodes were produced using a sol-enhanced electrodeposition technique from methanesulfonate electrolytes. The surface microstructures of observed, and their phase constituents determined. features analyzed by X-ray photoelectron spectroscopy. Linear sweep voltammetry degradation tests also conducted to determine the performance. results show that addition T...