On‐line Quality Control of Coated Glass. On‐line Qualitätskontrolle von beschichtetem Glas

Properties of optical coatings (e.g. low‐e or solar control) can be described and controlled using transmittance, reflectance and sheet resistance measurements. Multiple in situ transmittance measurement points allow a quick response to adjust different coating processes (layer thickness and homogeneity). For the final characterization of the coated substrate ex situ transmittance, reflectance and sheet resistance measurements are used. Accurate and reproducible measurements in a combination with Reverse Engineering methods admit monitoring all layers and in this way detecting slight drifts.     

Hochproduktive PVD-Großflächenbeschichtung von Aluminiumbändern zum Zwecke der Reflexionserhöhung

Highly productive large area coating of aluminium strips for enhancing their reflectivity Energy economizing is a more and more essential demand of industries. Thus the illumination industries are looking for possibilities of enhancing the lighting efficiency especially by increasing the reflectance of the basic reflection materials. The ecologically beneficial PVD-techniques are the preferential means for depositing reflection increasing layerstacks in large area mass production. In this way finished strips obtain more than 15 % higher illumination efficiency. von Ardenne Anlagentechnik developed a highly productive large area PVD-coating technology and built up a continuous production plant for Alanod Aluminiumveredlung GmbH in Germany. Metal strips of up to 1250 millimeters width passing the line attain a reflectance of 96 %. The layer parameters are measured by in situ ellipsometry at the surface of the moved strip. The highly productive solution of the task as well as the market presence of reflection enhancing large area products with economized costs open up new possibilities for solving similar multilayer deposition tasks as well.     

Nanoporous organosilicas as preconcentration materials for the electrochemical detection of trinitrotoluene

We describe the use of nanoporous organosilicas for rapid preconcentration and extraction of trinitrotoluene (TNT) for electrochemical analysis and demonstrate the effect of template-directed molecular imprinting on TNT adsorption. The relative effects of the benzene (BENZ)- and diethylbenzene (DEB)-bridged organic-inorganic polymers, having narrow or broad pore size distributions, respectively, on electrochemical response and desorption behavior were examined. Sample volumes of 0.5-10 mL containing 5-1000 ppb TNT in a phosphate-buffered saline buffer were preconcentrated in-line before the detector using a microcolumn containing 10 mg of imprinted BENZ or DEB. Square-wave voltammetry was used to detect the first reduction peak of TNT in an electrochemical flow cell using a carbon working electrode and a Ag/AgCl reference electrode. Imprinted BENZ released TNT faster than imprinted DEB with considerably less peak tailing and displayed enhanced sensitivity and an improvement in the limit of detection (LOD) owing to more rapid elution of TNT from that material with increasing signal amplitude. For imprinted BENZ, the slope of signal versus concentration scaled linearly with increasing preconcentration volume, and for preconcentrating 10 mL of sample, the LOD for TNT was estimated to be 5 ppb. Template-directed molecularly imprinted DEB (TDMI-DEB) was 7-fold more efficient in adsorption of TNT from aqueous contaminated soil extract than nonimprinted DEB.     

An Elastomeric Poly(Thiophene‐EDOT) Composite with a Dynamically Variable Permeability Towards Organic and Water Vapors

An interpenetrating polymer network (IPN) material with controllable nanoporosity is developed for applications such as chemical protection. The IPN material is based on a conducting polymer backbone consisting of thiophene and 3,4 ethylenedioxythiophene (EDOT) repeat units–poly(thiophene‐EDOT)–formed within a soft polyurethane support. The IPN demonstrates reversible, electrochemically switchable nanoporosity in the absence of standard liquid electrolyte, with the oxidized state being the open (high porosity) state and the reduced state being the closed (low porosity) state. The switching of the IPN between its oxidized (open) and reduced (closed) states is actuated using application of ±1.0 V. The variability in the IPN porosity, induced by the electrochemical switching, is revealed by large changes in water vapor diffusivity, as well as changes in the diffusivities of the chemical agent simulants chloroethyl ethyl sulfide (CEES) and methyl salicylate (MeS). The closed state of the IPN is able to decrease CEES diffusivity by ≈99% compared to expanded Teflon (ePTFE), while the open state allows high MVT rates comparable to ePTFE. The IPN's ability to allow high MVT under non‐threat conditions (open state) and high protection from agents under threat conditions (closed state) is a unique and desirable characteristic of this novel IPN material.     

Cavity resonance suppression in power delivery systems using electromagnetic band gap structures

The utilization of electromagnetic band gap (EBG) structures is a new and promising approach in plane pair noise cavity resonance suppression. In this paper, EBG/plane pair structures are studied with full-wave methods and results are experimentally verified. A new equivalent circuit modeling approach of characterizing the frequency behavior of the entire EBG/plane pair structure is presented. The equivalent circuit of the unit cell is proposed and the procedure to extract circuit parameters is described. The influence of EBG patch parameters on the band gap characteristics is quantified and the results provide some design rules to circuit designers. Examples of applications of EBG structures to power/ground plane noise suppression are given.     

Pattern characteristics of linear arrays using the constrained least squares distribution

The constrained least squares (CLS) distribution is a method for obtaining distribution functions that yield low sidelobe patterns with specified constraints on the aperture efficiency, and are especially useful for the transmit patterns of active array antennas. The widely used Taylor distribution optimizes only pattern performance while the CLS distribution optimizes pattern performance while taking into account the constraints on both the peak element amplitude and the total effective radiated voltage (ERV) of the aperture distribution. The paper compares the pattern characteristics of linear arrays with CLS and Taylor distributions. The results help to establish guidelines on when a CLS distribution would be preferable over a Taylor distribution when a specified aperture efficiency is important.     

Acoustic Fabrication via the Assembly and Fusion of Particles

Acoustic assembly promises a route toward rapid parallel fabrication of whole objects directly from solution. This study reports the contact‐free and maskless assembly, and fixing of silicone particles into arbitrary 2D shapes using ultrasound fields. Ultrasound passes through an acoustic hologram to form a target image. The particles assemble from a suspension along lines of high pressure in the image due to acoustic radiation forces and are then fixed (crosslinked) in a UV‐triggered reaction. For this, the particles are loaded with a photoinitiator by solvent‐induced swelling. This localizes the reaction and allows the bulk suspension to be reused. The final fabricated parts are mechanically stable and self‐supporting.     

Functionalized organosilicate materials for irritant gas removal

Organosilicate materials functionalized through post-synthesis grafting have been evaluated for their potential to remove irritant gases. Organosilicate scaffolds were synthesized through a technique combining surfactant-templating and phase separation to produce a macro-textured scaffold with a combination of micro- and mesopores. This structure facilitates diffusion through the sorbent material providing enhanced access to the available surface area. Post-synthesis grafting was used to incorporate amine and isocyanate groups on the surfaces of the pore walls in an attempt to modify the binding and reactive character of the materials. These modified materials were compared to the unmodified organosilicate scaffold. The removal of irritant gases including ammonia, sulfur dioxide, cyanogen chloride, and octane was evaluated for the materials variants. Results have been compared to the removal of the gases by carbons as well as other materials reported in recent literature.