Plasma cleaning of ITER first mirrors in magnetic field

To avoid reflectivity losses in ITER optical diagnostic systems, plasma sputtering of metallic First Mirrors is foreseen in order to remove deposits coming from the main wall (mainly beryllium and tungsten). Therefore plasma cleaning has to work on large mirrors (up to a size of 200*300 mm) and under the influence of strong magnetic fields (several Tesla). This work presents the results of plasma cleaning of aluminium and aluminium oxide (used as beryllium proxy) deposited on molybdenum mirrors. Using radio frequency (13.56 MHz) argon plasma, the removal of a 260 nm mixed aluminium/aluminium oxide film deposited by magnetron sputtering on a mirror (98 mm diameter) was demonstrated. 50 nm of pure aluminium oxide were removed from test mirrors (25 mm diameter) in a magnetic field of 0.35 T for various angles between the field lines and the mirrors surfaces. The cleaning efficiency was evaluated by performing reflectivity measurements, Scanning Electron Microscopy and X-ray Photoelectron Spectroscopy.Comment: 5 pages, 6 figures and 1 table. Results presented on the 21st Plasma Surface Interaction conference held in Kanazawa Japan, May 201

Les étiquettes anciennes du vin d’Alsace

Aujourd’hui les mentions portées sur l’étiquette de vin sont définies par des décrets et contrôlées par les services de la répression des fraudes, même en l’absence du millésime, on peut les situer dans le temps. Les anciennes étiquettes de vin d’Alsace millésimées sont rares. Pour identifier et dater les étiquettes non millésimées, il y a d’abord l’imagerie et le style graphique, puis l’histoire qui en change les marchés, l’Alsace est française et allemande à tour de rôle, vignoble en survie pendant la crise phylloxérique, la crise des vins artificiels et celles des surproductions du XXe siècle, l’ambition et l’assurance retrouvée après l’obtention de l’AOC et, après la deuxième guerre, la volonté d’exister à l’échelon international à l’égal d’autres régions comme la Champagne, le Bordelais et la Bourgogne. S’y ajoutent progressivement à partir de la fin du XIXe siècle les lois régissant le vin et son commerce, l’évolution des techniques d’impression et récemment la hiérarchisation du produit, Grand Cru, Crémant, Vendange Tardive, Sélection de Grain Noble, Appellation Intermédiaire.Nowadays the mentions printed on a wine bottle are clearly regulated by law and monitored by fraud prevention services, so that, without any vintage indicated, it is possible to date it. Old labels with Alsace wine vintage are rarely to be found. To identify and date such bottles, you first have the pictorial and graphic style, or history which are decisive: Alsace was alternately French and German, vineyards survived the phylloxera ailment with difficulty, the crisis caused by artificial wines and overproduction in the 20th century, a new sense of ambition and self-confidence after being awarded the AOC appellation, and (after World War II) the determination to be on an equal footing with other wine regions like Champagne, Bordelais or Bourgogne. Gradually, from the late 19th century onward, new laws ruled the wine trade, the evolution of the printing techniques and, more recently, the hierarchisation of wines: Grand Cru, Crémant, Vendanges Tardives, Sélection de Grain Noble, Appellation Intermédiaire.Was heute auf den Weinetiketten steht, wird von Dekreten bestimmt und von einer staatlichen Behörde kontrolliert. Auch wenn der Jahrgang nicht ausdrücklich vermerkt ist, kann man ihn in eine Zeitspanne einordnen. Elsässische Weinetiketten aus früheren Zeiten, auf denen der Jahrgang verzeichnet ist, sind selten. Um festzulegen, aus welchem Jahr das Etikett stammt, gibt es viele Wege und Hinweise. Da ist zunächst das, was darauf abgebildet ist sowie der graphische Stil, dann die Geschichte, die die Märkte verändert hat, das Elsaß ist abwechselnd französisch und deutsch, der Weinberg in der Zeit, in der er unter der Reblaus leidet, die Krise, die die künstlich hergestellten Weine und die Überproduktion des 20. Jh. verursacht haben, der wiedererlangte Glaube an den Wein und die Sicherheit nach der Erteilung der Klassifikation AOC (Appellation d’Origine Contrôlée = amtliche Herkunftsangabe) und – nach dem zweiten Weltkrieg – das Bestreben, auf internationaler Ebene anderen Regionen, wie der Champagne, dem Bordeaux, dem Burgund ebenbürtig zu sein. Dazu kommen nach und nach seit Beginn des XIX. Jh. die Gesetze, die den Wein und den Weinhandel regeln, der Fortschritt in der Drucktechnik und neuerdings die hierarchische Einordnung der Produkte: die Bezeichnungen Grand Cru (Großes Gewächs), Crémant, Vendange Tardive (Spätlese), Sélection de Grain Noble (Trockenbeerenauslese), Übergangsbezeichnungen

Neue empirische Befunde zur Preissetzung und zum Verbraucherverhalten im Lebensmitteleinzelhandel

There are two objectives of this article: (i) It is discussed theoretically how the dynamics of pricing decisions of multiproduct retailers can be explained. (ii) It is analyzed empirically by use of scanner data how prices are actually set and how consumers react at the point of sale to price changes and promotional activities by retailers. The empirical evidence focuses on breakfast products in general and jam and breakfast cereals in particular. Main results are the following: 1. Theory of optimal pricing by multiproduct firms suggests that direct and cross price elasticities of demand and marginal costs determine the profit-maximizing price at one point of time. Good reasons do exist additionally for multiproduct retailers to vary prices intertemporally. Sales, e.g., can be consistent with optimal intertemporal pricing. 2. Scanner data for German food retailers in the period September 1996 – June 1999 are utilized in the empirical analysis. The law of one price does not hold for individual branded foods across store types. Price dispersion varies by product. The impact of sales is high in grocery retailing; on average for 20 food categories, one product of a category was on sale every other week. 3. Promotional activities affect demand for branded products strongly, but impacts on quantities varied widely. They were above average for coffee, a storeable product, below average for fresh milk, a less storeable good. In some cases, these effects are so strong that consumers seem to buy the brand only when it is on sale. 4. In the special case of jam, prices are lowest in discounters and highest in supermarkets. The spread of prices is also lowest in discounters and highest in supermarkets. Price-elastic reactions at the point of sale was, however, a uniform pattern across all store types of grocery retailing. The strongest reaction was found in supermarkets with a price elasticity of demand of –5.09. 5. For breakfast cereals, strong reactions by consumers occur to various promotional activities. Impacts on demand were, e.g., as high as 175 % when the instruments sales, display and leaflet were combined. Sales were an important feature of promotional activities with a strong demand-increasing effect. Summing up, it can be concluded that an active price policy of grocery retailers is a crucial component of their marketing mix. This is compatible with the finding of a strong price responsiveness of consumers. The stylized fact that the price elasticity of food demand is absolutely low, may be correct for aggregate demand but is not confirmed at the store level. On the contrary: High absolute levels of the store-level price elasticity of demand are typical for branded foods.food retailing, scanner data, price policy, food demand, store-level, price elasticity, multiproduct firms, jam, breakfast cereals, Agribusiness, Demand and Price Analysis,

Precise positioning using the electrostatic glass motor

Precise positioning over a long stroke is required in various fields. Important advances in the field of electromagnetic motors, piezoelectric actuators and bearing technology allow nanometric and sub-arc-second resolution for linear or rotary actuators, respectively. Alas, these devices are rather complex, therefore expensive, and require sophisticated assembly techniques for the delicate components. Furthermore, their operation range is often limited to some fractions of a millimeter or a couple of degrees. For some applications the stiffness of the positioning stage is of minor importance. Compactness, cost-effectiveness (simple structure), ripple-free displacements and rotations and the absence of magnetic fields are the design objectives. Potential applications requiring such specifications are typically the positioning of optical elements such as mirrors and lenses and the handling of wafers during electron-beam operations. This thesis presents a novel approach to precise positioning, by exploiting the electrical properties of glasses. Charges are arranged via application of an electrostatic field. This polarization has an extraordinary long rise and decay time constant in the order or several tens of seconds and can be used to drive the glass. It was verified experimentally that what we call the "electrostatic glass motor" is operating at the speed of the applied field, although being a kind of induction motor. It features a perfect ripple-free movement over a very broad speed range. The precision of the movement depends on the resolution of the motor field generator and is entirely decoupled form mechanical precision aspects. In the present report, the principle of the electrostatic glass motor is presented. An analytical model, describing the forces and torques of such motors is proposed and verified experimentally. A rotary positioning device, allowing sub-arc second open loop resolution has been designed, realized and characterized. An open-loop resolution of 0.3 arc-seconds and a speed range ranging from 40 rpm down to 0.3 arc-sec/sec, and this over an unlimited displacement range, indicate the promising potential of the presented concept. Models and design rules for electrostatic glass positioning devices have been established and allow, within the scope of future works, the definitions of linear and multi-axis devices

An Assessment of a Model for Error Processing in the CMS Data Acquisition System

The CMS Data Acquisition System consists of O(20000) interdependent services. A system providing exception and application-specific monitoring data is essential for the operation of such a cluster. Due to the number of involved services the amount of monitoring data is higher than a human operator can handle efficiently. Thus moving the expert-knowledge for error analysis from the operator to a dedicated system is a natural choice. This reduces the number of notifications to the operator for simpler visualization and provides meaningful error cause descriptions and suggestions for possible countermeasures. This paper discusses an architecture of a workflow-based hierarchical error analysis system based on Guardians for the CMS Data Acquisition System. Guardians provide a common interface for error analysis of a specific service or subsystem. To provide effective and complete error analysis, the requirements regarding information sources, monitoring and configuration, are analyzed. Formats for common notification types are defined and a generic Guardian based on Event-Condition-Action rules is presented as a proof-of-concept

Optical beam guidance in monolithic polymer chips for miniaturized colorimetric assays

For the first time, we present a simple and robust optical concept to enable precise and sensitive read-out of colorimetric assays in flat lab-on-a-chip devices. The optical guidance of the probe beam through an incorporated measurement chamber to the detector is based on the total internal reflection at V-grooves in the polymer chip. This way, the optical path length through the flat measurement chamber and thus the performance of the measurements are massively enhanced compared to direct (perpendicular) beam incidence. This is demonstrated by a chip-based, colorimetric glucose-assay on serum. Outstanding features are an excellent reproducibility (CV= 1.91 %), a competitive lower limit of detection (cmin = 124 μM), and a high degree of linearity (R2 = 0.998) within a working range extending over nearly three orders of magnitude

The Process Matters: Fairness in Repository Siting For Nuclear Waste

Siting contested infrastructure such as repositories for nuclear waste very often faces strong local resistance. One major reason for this opposition may arise because siting processes do not appropriately consider fairness issues such as transparency, the availability of options, or the sufficient involvement of concerned and affected people. The aim of this study was to analyze people's concerns related to justice in siting nuclear waste. Besides procedural aspects, both distributive justice and outcome valence are considered important and therefore the "total fairness model” by Törnblom and Vermunt (Soc Justice Res 12:39-64, 1999) was used as a framework. In three quasi-experimental studies (N 1=53; N 2=56; N 3=83) applying conjoint analysis, respondents ranked 11 vignettes with the three attributes procedural justice, distributional justice, and outcome valence. Each vignette represents a realistic scenario of a site selection process for the disposal of nuclear waste in Switzerland. All the three studies yield a consistent result: vignettes representing a situation with a fair process are top-ranked by respondents; situations with negative outcome valence are ranked lowest; distributive issues turned out to be of minor importance. We conclude that procedural fairness should be given more attention in any kind of contested infrastructure siting and that real-world examples like the one discussed here can inform justice researc

TRIPILLAR: a miniature magnetic caterpillar climbing robot with plane transition ability

We present a miniature magnetic climbing robot with dimensions 96 × 46 × 64 mm3. With two degrees of freedom it is able to climb ferromagnetic surfaces and to make inner plane to plane transitions whatever their inclination is. This robot, named TRIPILLAR, combines triangular-shaped magnetic caterpillars and frame magnets. This particular configuration allows, for example, to move from ground to wall and ceiling and back. This achievement opens new avenues to use mobile robotics for industrial inspection with stringent size restrictions, such as the ones encountered in power plant

Ion flux-energy distributions across grounded grids in an RF plasma source with DC-grounded electrodes

We present an experimental investigation of the ion flux–energy distribution functions (IFEDFs) obtained across grounded grids in an asymmetric capacitively coupled RF source using a helium discharge. The powered electrode in the RF source is DC-grounded via a λ/4 filter, which lifts its DC potential to zero. Grids of different dimensions (hole width, thickness, and geometric transparency) were used to confine the plasma, while the IFEDF of the ion beam departing the grid and reaching the reactor walls was studied using a retarding field energy analyser. The IFEDF obtained was double-peaked, indicating the presence of fast ions arriving from the plasma source, and cold ions generated upon charge exchange collisions between the fast ions and neutrals. The flux, as well as the peak energies of the two ion groups, depended significantly on the process parameters: RF power, He pressure, the distance between grids and walls, and the dimensions of the grids. The results indicate that confining plasma with grids can reduce the ion flux at the walls by over 60%, significantly lowering the wall sputtering rate. This was confirmed with a dedicated long-exposure plasma discharge with a gridded plasma reactor, wherein less than 1 nm of Cu deposition was found on the DC-grounded powered electrode, and the surface reflectivity was preserved to pristine values. In contrast, a similar experiment in a gridless reactor resulted in Cu deposition of 35 nm with a drastic drop in surface reflectivity. These studies are of great importance for the application of similar RF plasma sources with in-situ cleaning of diagnostic mirrors in fusion devices, as well as in a variety of plasma processing applications