Localization of formaldehyde production during frozen storage of European hake (Merluccius merluccius)

The formation of dimethylamine and formaldehyde from trimethylamine N-oxide by the enzyme trimethylamine N-oxide demethylase in whole hake during frozen storage was studied. The objective was to check if there were parts of the muscle with a higher production of dimethylamine and formaldehyde, and if the presence of kidney during frozen storage had any significant influence on the production. Three variables were examined through one year storage. The first was anatomical location, considering the red muscle and three zones of white muscle, one located right over the kidneys, the dorsal part over the viscera, and the tail. The second variable was the temperature of storage, -11 °C or -18 °C. Finally, the influence of kidneys during storage, comparing fish with and without kidneys, was also evaluated. No differences were found in dimethylamine and formaldehyde production between fish with and without kidneys stored at -18 °C. However at -11 °C the amounts of dimethylamine and formaldehyde detected in fish without kidneys were, in some cases, higher than in those with kidneys. Kidney removal does not have a statistically significant influence on DMA and FA production in frozen storage hake. Differences in dimethylamine and formaldehyde values among different anatomical locations were found, especially in those stored over one year. It was found that, in general, the white muscle located right over the kidneys produced more dimethylamine than other parts of the fish.     

Elektrochrome Beschichtungen

Electrochromic Coatings – Solar Control Glazing of a New Generation Since the early sixties of the 20th century the permanent expanded quantities and qualitative requirements for coatings on architectural glass have pushed the development of the processing technology. Today the magnetron‐sputter technology is the standard for coating of broadsheet architectural‐ and car glass. It provides a huge range of variation in case of processing parameters and it is therefore best suited to realize the next generation of architectural glazing based on electrochromic coatings. The history and background information's to the requirements of coating technology will be discussed. Finally there are two examples for switchable solar control glazing in a building.     

Alaskan flatfishes on the German market: part 1: identification by DNA and protein analytical methods

North Pacific flatfishes are gaining increased popularity on the German market. Isoelectric focusing of sarcoplasmic proteins and PCR-based DNA analysis were applied to identify fillets of nine Alaskan Flatfish species: Artheresthes stomias (Arrow-tooth flounder), Limanda aspera (Yellowfin sole), Isopsetta isolepis (Butter sole), Lepidopsetta bilineata (Southern rock sole), Lepidopsetta polyxystra (Northern rock sole), Hippoglossus stenolepis (Pacific halibut), Hippoglossoides elassodon (Flathead sole), Platichthys stellatus (Starry flounder), and Glyptocephalus zachirus (Rex sole). Characteristic protein patterns were obtained for raw fillets of several species. Reactivity of flatfish DNA against five pairs of primers was tested, amplifying segments of the mitochondrial cytochrome b, cytochrome oxidase subunit I, 16S rRNA gene, as well as the nuclear parvalbumin gene. Amplicons of the cytochrome b gene were sequenced and used for single-strand conformation polymorphism analysis. The survey of deep-frozen commercial yellowfin sole fillets resulted in the detection of 17% of the fillets being mislabelled; Northern rock sole, butter sole and flathead sole had been used as substitutes.     

Imaging and Spectroscopic Sensing with Low-Repetition-Rate Terahertz Pulses and GaN TeraFET Detectors

Aiming for non-destructive testing and security applications, we investigate transmission-mode imaging and spectroscopic sensing using terahertz (THz) pulses from a commercial optical parametric oscillator (OPO) in combination with THz detectors based on antenna-coupled field-effect transistors (TeraFETs). The Q-switched OPO generates quasi-continuous-wave THz pulses with a peak power of up to 1 W at a repetition rate between 12 and 90 Hz. The pulses are frequency-tunable between 0.7 and 2.6 THz with a typical linewidth of 50 GHz. We explore detection with fast GaN/AlGaN TeraFETs which hold the potential for multi-pixel and homodyne detection.     

Local Structure Fixation in the Composite Manufacturing Chain

Compared to metal materials, textile reinforced composites show interesting features, but also higher production costs because of low automation rate in the manufacturing chain at this time. Their applicability is also limited due to quality problems, which restrict the production of complex shaped dry textile preforms. New technologies, design concepts, and cost-effective manufacturing methods are needed in order to establish further fields of application. This paper deals with possible ways to improve the textile deformation process by locally applying a fixative to the structure parallel to the cut. This hinders unwanted deformation in the textile stock during the subsequent stacking and formation steps. It is found that suitable thermoplastic binders, applied in the appropriate manner do not restrict formation of the textile and have no negative influence on the mechanical properties of the composite.     

Comparison of methods for calculating the influence of asymmetry in strip and plate rolling

The effect of different work roll diameters, different circumferential speeds of work rolls, and different friction for top and bottom side on roll parameters, especially on curvature of outgoing material, is investigated. Three methods, which are all based on the theorem of the upper bound of total power, are discussed. Their results are compared with experimental data of Juretzek. They differ in the kind of velocity field for the material flow in the roll gap. The first makes use of a polynomial global velocity field. The second employs bilinear quadrilateral finite elements, which are fixed to space, while the stationary rigid plastic material flow goes through (stationary FEM). The third field consists of rigid triangles which can slide along their contact lines. The last method produces a formation of shear lines, which is in good coincidence with that of the zones of high strain rate, given by stationary FEM. Results of parameter studies using stationary FEM are shown as relationship between dimensionless characteristic numbers. At last a comparative analysis of the effectiveness of the different methods is given.     

MSM Actuators: Design Rules and Control Strategies

Magnetic shape memory (MSM) alloys are comparatively new active materials which can be used for several industrial applications, ranging from precise positioning systems to advanced robotics. Beyond the material research, which deals with the basic thermo‐magneto‐mechanical properties of the crystals, the design as well as the control of the actuators displacement is an essential challenge. This paper addresses those two topics, trying to give to the reader a useful overview of existing results, but also presents new ideas. First, it introduces and discusses in details some possible designs, with a special emphasis on innovative actuator design concepts which are able to exploit the particular potentialities of MSM elements. The second focus of the paper is on the problem of designing a controller, i.e., an algorithm that allows to obtain a required performance from the actuator. The proposed control strategies try to take into account two main characteristics of MSM elements: the hysteresis and the temperature dependence. The effectiveness of the strategies is emphasized by experimental results performed on a commercially available MSM actuator demonstrator.     

A precise positioning actuator based on feedback-controlled magnetic shape memory alloys

This paper describes a precise positioning system based on magnetic shape memory alloys (MSMAs). This new type of material shows an interesting potential in the area of mechatronics due to its outstanding magnetically-induced strain, which is significantly larger than the one exhibited by other common active materials such as piezoelectric ceramics. However, MSMAs still have not found their way into industrial applications mainly due to their high hysteretic behavior and the strong sensitivity to temperature changes. The aim of this paper is to present the main challenges of using MSMAs for precise positioning systems by means of a simple yet effective experimental prototype. In particular, this paper examines the problem of effectively controlling the device in closed-loop. The performance of an adaptive hysteresis compensator based on the Preisach-like Krasnosel’skii–Pokrovskii model is analyzed and evaluated in the presence of temperature changes. Experiments confirm that the undesirable effects of temperature on the precision of the device can be partially addressed with an adaptive model-based algorithm devised to cope with time-varying nonlinearities.     

Assessment of DEMO challenges in technology and physics

The challenges that DEMO designs encounter in both technology and physics are reviewed. It is shown that it is very important to respect the interlinks between these fields when developing designs for DEMO. Examples for areas where such interlinks put very strict requirements are the development of a steady state tokamak operation scenario and the question of power exhaust taking into account the boundary conditions set by materials questions. Concerning steady state operation, we find that demands on the physics scenario are so high that pulsed operation of a tokamak DEMO should seriously be considered in conservative DEMO designs. Alternatively, the device could foresee a large fraction of externally driven current which calls for optimization of both plasma CD efficiency as well as wall plug efficiency of the CD system. In the exhaust area, a realistic estimate of the admissable time averaged peak heat flux at the target is of the order of 5 MW/m², leading to strict requirements for the operational scenario, which has to rely on an unprecedented high level of radiation loss by impurity seeding and the facilitation of partial detachment. Thus, exhaust scenarios along these lines have to be developed which are compatible with the confinement needs and the H-L back transition power for DEMO. In both areas, we discuss possible risk mitigation strategies based on conceptually different approaches.