Search results for "QUARTZ"

Biochemical Applications of Solid Supported Membranes on Gold Surfaces: Quartz Crystal Microbalance and Impedance Analysis

2003

Since their inception in 1985 by Tamm and McConnell [1], solid supported lipid bilayers have been widely used as model systems for cellular membranes [2]. They have been applied in fundamental and applied studies of lipid assemblies on surfaces, to study the structure of membranes and membrane dynamics, lipidreceptor-interactions and electrochemical properties of membranes [3-5]. Several attempts have been made to apply solid supported membranes (SSM) in biosensor devices [6]. Planar lipid membranes can be formed on various surfaces, i.e. glass, silicon, mica or metal surfaces such as platinum or gold. Surface attachment of the lipids is typically achieved following two different strategies…

Mass/charge balance as a tool to estimate dimensional change in polypyrrole-based actuators

2006

The deconvolution of the voltammograms of polypyrrole electrochemistry has proved to be possible through the electrochemical quartz crystal microbalance data using the F(dm/dQ) function. This deconvolution allows the evolution of the thickness of the polypyrrole films during their redox processes to be estimated and therefore, the mechanical contraction/decontraction of this polymer as a function of the ionic exchange processes can be evaluated. Keywords: Polypyrrole, EQCM, Thickness change

Evidence for Conformational Mechanism on the Binding of TgMIC4 with β-Galactose-Containing Carbohydrate Ligand

2015

A deeper understanding of the role of sialic/desialylated groups during TgMIC4-glycoproteins interactions has importance to better clarify the odd process of host cell invasion by members of the apicomplexan phylum. Within this context, we evaluated the interaction established by recombinant TgMIC4 (the whole molecule) with sialylated (bovine fetuin) and desialylated (asialofetuin) glycoproteins by using functionalized quartz crystal microbalance with dissipation monitoring (QCM-D). A suitable receptive surface containing recombinant TgMIC4 for monitoring β-galactose-containing carbohydrate ligand (limit of quantification ∼ 40 μM) was designed and used as biomolecular recognition platform t…

Characterization of an early metamorphic stage through inclusions in zircon of a diamondiferous quartzofeldspathic rock from the Erzgebirge, Germany

2003

About 1000 zircon grains from a diamondiferous quartzofeldspathic rock of the Saxonian Erzgebirge were investigated for inclusions using optical microscopy and confocal laser-Raman spectroscopy. Cathodoluminescence imagery was applied to characterize the growth zone of zircon where the inclusions occurred. The most abundant inclusion minerals are microdiamonds. Coesite was not detected. However, garnet and jadeite occur as rare inclusions in zircon cores where diamonds are lacking. Jadeite was detected for the first time in quartzofeldspathic rocks from the crystalline complex of the Erzgebirge. The compositions of the pristine garnets in the zircons are similar to those of core areas of mi…

Synthesis of 9,9′-Spirobifluorenes and 4,5-Diaza-9,9′-spirobifluorenes and Their Application as Affinity Materials for Quartz Crystal Microbalances

2017

Two different classes of aza analogues of 9,9'-spirobifluorenes have been synthesized. These were obtained by either furnishing the spirobifluorene with additional pyridyl moieties or by installing the aza function directly into the spirobifluorene core. These structurally rigid compounds were then evaluated as affinity materials for quartz crystal microbalances and proved to be highly potent for the detection of volatile organic compounds.

Tracks induced in TeO2 by heavy ions at low velocities

2000

On the basis of its thermal properties, TeO2 crystal was selected as an insulator with low threshold electronic stopping power for track formation Set. The crystals were irradiated by S, Zn, Mo, Kr, Te and Pb ions and the optical absorption and track formation were studied. Comparison is made with the published results on LiNbO3 ,Y 3Fe5O12 and SiO2 quartz. Good quantitative agreement is found with the predictions of the thermal spike model of Szenes with respect to Set and the variation of the track size with the electronic stopping power Se. It is shown that TeO2 has a high eAciency g at low ion velocities, which is a characteristic feature of the damage cross-section velocity eAect. ” 200…

Cover Picture: Scaffold-Optimized Dendrimers for the Detection of the Triacetone Triperoxide Explosive Using Quartz Crystal Microbalances (ChemPlusCh…

2012

Scaffold-Optimized Dendrimers for the Detection of the Triacetone Triperoxide Explosive Using Quartz Crystal Microbalances

2012

Effect of cyclic loading on fracture strength and microleakage of a quartz fiber dowel with different adhesive, cement and resin core material combin…

2010

Background: This study evaluated the performance of different adhesive-cement-core combinations coupled with quartz fiber dowels after cyclic loading and fracture strength tests and assessed the microleakage using dye penetration method. Methods: Forty maxillary canines (n=10 per group) were restored with fiber dowels (Quartz fiber DT Light Post) and four adhesive-cement-core material combinations [(Group 1: All-Bond 2+C&B (root) / All-Bond 2+Biscore (core); Group 2: All-Bond 2+Bisfil 2B (root) / All-Bond 2+Bisfil 2B (core); Group 3: Scotchbond 1+RelyX ARC (root) / Scotchbond 1+Supreme (core); Group 4: RelyX Unicem (root) / Scotchbond 1+Filtek Supreme (core)]. The specimens were initially c…

δ30Si and δ29Si Determinations on USGS BHVO-1 and BHVO-2 Reference Materials with a New Configuration on a Nu Plasma Multi-Collector ICP-MS

2008

We report silicon isotopic determinations for USGS rock reference materials BHVO-1 and BHVO-2 using a Nu Plasma multi-collector (MC)-ICP-MS, upgraded with a new adjustable entrance slit, to obtain medium resolution, as well as a stronger primary pump and newly designed sampler and skimmer cones ("B" cones). These settings, combined with the use of collector slits, allowed a resolution to be reached that was sufficient to overcome the (NO)-N-14-O-16 and N-14(2) interferences overlying the Si-30 and the Si-28 peaks, respectively, in an earlier set-up. This enabled accurate measurement of both delta Si-30 and delta Si-29. The delta value is expressed in per mil variation relative to the NBS 28…