Industrial experiences of electric filtration in vegetable oil technology

Electric filtration is used to remove bleaching earth and other electrically charged particles from vegetable oils and fats. The grain size of bleaching earth does not significantly influence its separation during application of electric filtration. Therefore, it will be possible to separate bleaching earth with very small grains and increased capability for adsorption. The generation of an electrical field in an insulating fluid is the physical basis of the electric filtration, and under these conditions the generated Coulomb-power moves the bleaching earth grains to one of the electrodes where they will be separated. Electric filtration is available for industrial use. A modular unit enables the testing of all industrial applications directly in the refinery, and it permits the fulfilment of the requirements for the integration of an ÖHMI filtration^® unit in the whole process. Tests on a laboratory and a pilot plant scale have supplied the basis for smooth running of the first industrial plant installed in a large German edible oil refinery. Compact electric filtration plants enable a bleaching earth filtration largely independent of the grain size of the bleaching earth; they reduce the consumption of electric power, they can be adapted to each capacity due to the construction principal of the filter cell moduls, they decrease all expenditure of cleaning and the wear of the filter elements and clothes compared to the conventional cake filtration.     

Evaluierung und Optimierung einer doppelschaligen Fassade mit Hilfe von Simulationen

Bei großflächig verglasten, mehrgeschossigen Bürogebäuden liegen doppelschalige, hinterlüftete Glasfassaden nach wie vor im gestalterischen Trend. Die Konstruktionsdetails der Fassade haben einen erheblichen Einfluss auf die sommerliche Überhitzung der Luft im Fassadenzwischenraum (FZR), in dem auch der Sonnenschutz platziert ist. Es empfiehlt sich daher, die Details einer doppelschaligen Fassade im Hinblick auf die sommerlichen Temperaturverhältnisse zu optimieren. Die üblichen Methoden einer standardmäßigen bauphysikalischen Planung sind für eine derartige Optimierung nur sehr bedingt verwendbar. Im vorliegenden Beitrag wird anhand des Projektes Neues K & H Bank‐Gebäude in Budapest exemplarisch aufgezeigt, wie mit Hilfe von moderner Simulationstechnik die Ausbildung einer doppelschaligen Fassade evaluiert und anschließend optimiert werden kann. Evaluation and optimization of a double skin façade with the help of computational simulations. Natural ventilated double skin façades still prove to be trendy design choices for multi‐story office buildings with large glazed surfaces. The construction design details of these façades have a significant impact on the summer overheating of the air in the façade cavity, in which the shading is positioned also. Therefore it is recommended to investigate and optimize the parameters of the double skin façade concerning the summer temperature conditions. The usual methods of standard building physical planning have limited application possibilities for optimizing these kinds of systems. Therefore in the following article through the example of the K°&°H Bank, Budapest, we are going to explain how the modern simulation techniques can support the constructional design of double skin façades first by evaluation, then subsequently, by optimization.     

Kinetics and Mechanistic Investigation of Hydrotalcite‐Catalyzed Melt Synthesis of Poly(ethylene terephthalate)

Summary: Hydrotalcite‐catalyzed polycondensation of BHET was studied by thermogravimetry to elucidate the kinetics. The reaction was found to follow second‐order kinetics with respect to hydroxyl end groups. The overall activation energy of the polycondensation was found to decrease with increasing catalyst concentration before it leveled out to the value of 93 kJ · mol⁻¹ at high catalyst concentration. This is a result of the uncatalyzed reaction that takes place parallel to the catalyzed one. The activation energy of the uncatalyzed path was found to be 156 kJ · mol⁻¹. IR spectroscopy and XRD showed that the monomer intercalates between the layers of hydrotalcite at the beginning of the reaction enabling the complexation of oxygen‐containing functional groups with the hydroxide groups of the catalyst. Based on these findings a polycondensation mechanism is proposed. One end group of the monomer is activated in the form of alkoxide that counterbalances the positive charge of the hydrotalcite layer. This alkoxide group attacks an ester carbonyl group fixed close to it, generating a new ester bond and a glycoxide species. The role of hydrotalcite is to activate the reactants, rendering the attacking hydroxyl group more nucleophilic and the ester carbonyl group more electrophilic, and at the same time fixing the reactant together in a favorable geometry.

Intercalation of BHET in the gallery of HT layers in a twisted alkoxide form.     

The impact response of motorcycle helmets at different impact severities

Helmets reduce the frequency and severity of head and brain injuries over a range of impact severities broader than those covered by the impact attenuation standards. Our goal was to document the impact attenuation performance of common helmet types over a wide range of impact speeds. Sixty-five drop tests were performed against the side of 10 different helmets onto a flat anvil at impact speeds of 0.9–10.1 m/s (energy = 2–260 J; equivalent drop heights of 0.04–5.2 m). Three non-approved beanie helmets performed poorly, with the worst helmet reaching a peak headform acceleration of 852g at 29 J. Three full-face and one open-face helmet responded similarly from about 100g at 30 J to between 292g and 344g at 256–260 J. Three shorty style helmets responded like the full-face helmets up to 150 J, above which varying degrees of foam densification appeared to occur. Impact restitution values varied from 0.19 to 0.46. A three-parameter model successfully captured the plateau and densification responses exhibited by the various helmets (R² = 0.95–0.99). Helmet responses varied with foam thickness, foam material and possibly shell material, with the largest response differences consistent with either the presence/absence of a foam liner or the densification of the foam liner.     

Feasibility of monitoring large wind turbines using photogrammetry

Photogrammetry, which is a proven measurement technique based on determination of the 3D coordinates of the points on an object by using two or more images taken from different positions, is proposed to be a promising and cost efficient alternative for monitoring the dynamic behavior of wind turbines. The pros and cons of utilizing this measurement technique for several applications such as dynamic testing or health monitoring of large wind turbines are discussed by presenting the results of the infield tests performed on a 2.5 MW - 80 m diameter - wind turbine.     

Child maltreatment moderates the association of MAOA with symptoms of depression and antisocial personality disorder.

There is a growing body of data indicating that Gene × Child Maltreatment interactions at monoamine oxidase A (MAOA) play a role in vulnerability to symptoms of antisocial personality disorder (ASPD) but not major depression (MD). Using a sample of 538 participants from the Iowa Adoption Studies, we introduce a conceptual model that highlights two distinct pathways from child maltreatment to symptoms of MD, suggesting that maltreatment has different effects depending on genotype and highlighting the importance of including the indirect pathway through ASPD. As predicted by the model, high activity alleles predispose to symptoms of MD in the context of child maltreatment whereas low activity alleles predispose to symptoms of ASPD. We conclude that the Gene × Environment interplay at this locus (MAOA) contributes to both symptoms of ASPD and MD and that careful specification of child maltreatment may be essential if genetic association research is to produce replicable results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Numerical Modeling of Turbulent Melt Flow in a Continuous Casting Mold Affected by an Electromagnetic Brake

The current work combines numerical and experimental investigations based on a small-scale mockup using the eutectic alloy GaInSn.The jet flow discharging from the submerged entry nozzle was exposed perpendicularly to a DC magnetic field across the entire wide face of the mold.Numerical calculations were performed by using the commercial package CFX with an implemented RANS-SST turbulence model.The anisotropic properties of the MHD turbulence were taken into account by specific modifications of the turbulence model.The comparison between our numerical calculations and the experimental results shows a very well agreement.In particular,the modified RANS-SST turbulence model is capable to reconstruct the peculiar phenomenon of the excitation of non-steady,non-isotropic large-scale flow perturbations caused by the application of the DC magnetic field.Another important finding of our study is the feature that the electrical boundary conditions,namely the wall conductivity ratio,have a great impact on the mold flow subjected to an external magnetic field.     

Japanese Manufacturing Techniques: Nine Hidden Lessons in Simplicity

Compound orthogonal arrays (COAs) and single arrays are alternatives to the inner–outer arrays advocated by Taguchi for robust parameter design experiments. A criterion based on the word type pattern and strength of COAs is proposed to select optimal COAs. Single arrays are classified into prodigal single arrays (PSAs) and economical single arrays (ESAs) according to their relative estimation capacities, and various optimality criteria, again based on the word type pattern, are proposed for selecting optimal single arrays. Useful optimal COAs, PSAs, and ESAs are constructed and tabulated as convenient references for experimenters in practice.