Composite Applications: Neue Verfahren für flexible Geschäftsprozesse

Zusammenfassung Es ist l?ngst eine Selbstverst?ndlichkeit: Durch die Globalisierung und dynamische M?rkte stehen Unternehmen st?ndig vor der Herausforderung, zentrale Gesch?ftsabl?ufe den Marktver?nderungen anzupassen und sich darüber hinaus durch Innovationen Wettbewerbsvorteile zu schaffen. Kosten und Nutzen müssen dabei in einem sinnvollen Verh?ltnis stehen.     

An integrated approach to design and engineering of intelligent buildings—The Intelligent Workplace at Carnegie Mellon University

In the past few years, there have been significant advances made in the design and engineering of “intelligent” workplaces, buildings that not only accommodate major advances in office technology but provide better physical and environmental settings for the occupants. This paper will briefly present recent approaches to the creation of innovative environments for the advanced workplace. The architectural and engineering advances demonstrated in Japan, Germany, North America, the United Kingdom, and France can be summarized in four major system categories: (1) enclosure innovations including approaches to load balancing, natural ventilation and daylighting; (2) heating, ventilation and air-conditioning (HVAC) system innovations including approaches to local control and improved environmental contact; (3) data/voice/power “connectivity” innovations; and (4) interior system innovations, including approaches to workstation and workgroup design for improved spatial, thermal, acoustic, visual and air quality.

In-depth international field studies of over 20 intelligent office buildings have been carried out by a multidisciplinary expert team of the Advanced Building Systems Integration Consortium (ABSIC) based at Carnegie Mellon University. ABSIC is a university-industry-government partnership focused on the definition and development of the advanced workplace. The ABSIC field team evaluated the component and integrated system innovations for their multidimensional performance qualities, through expert analysis, occupancy assessments and field diagnostics.

Based on the results of the case studies and building on the most recent technological advances, the ABSIC team developed the concepts for the Intelligent Workplace, a 7000 square foot living laboratory of office environments and innovations. This project is now under construction at Carnegie Mellon University and its features are discussed in the second section of this paper.     

Applications of LIGA technology to precision manufacturing of high-aspect-ratio micro-components and -systems: a review

The by far leading technology for manufacturing MEMS devices is Si-micromachining with its various derivatives. However, many applications of microsystems have requirements on materials basis, geometry, aspect ratio, dimensions, shape, accuracy of microstructures, and number of parts that cannot be fulfilled easily by mainstream silicon-based micromachining technologies. LIGA, an alternative microfabrication process combining deep X-ray lithography, plating-through-mask and molding, enables the highly precise manufacture of high-aspect-ratio microstructures with large structural height ranging from hundreds to thousands of micrometers thick. These tall microstructures can be produced in a variety of materials with well-defined geometry and dimensions, very straight and smooth sidewalls, and tight tolerances. LIGA technology is also well suited for mass fabrication of parts, particularly in polymer.Many microsystems benefit from unique characteristics and advantages of the LIGA process in terms of product performance. The LIGA technology is briefly reviewed. The strengths of the manufacturing method and its main fields of application are emphasized with examples taken from various groups worldwide, especially in micromechanics and microoptics.     

Synthesis and polymerization of hydrophobic iodine-containing methacrylates

Starting from 2,4,6-triiodophenol, 2,3,5-triiodobenzoic acid and 3,5-bis(acetylamino)-2,4,6-triiodobenzoic acid, polymerizable methacrylates were synthesized and characterized by elemental analyses, IR, ¹H-NMR and ¹³C-NMR spectroscopy. The iodine-containing methacrylates show a different radical polymerization behaviour. 2,4,6-Triiodophenyl methacrylate gives only oligomeric products in the presence of azoisobutyronitrile (AIBN), whereas 2-methacryloyloxyethyl 2,3,5-triiodobenzoate yields polymers. On the basis of mixtures of isomeric 1,3-dimethacryloyloxy-2- and 1,2-dimethacryloyloxy-3-(2,3,5-triiodobenzoyloxy)propane with usual crosslinking monomers, radiopaque materials were prepared.     

Determination of the adsorption character of cellulose fibres using surface tension and surface charge

The reactivity and adsorption properties of cellulose fibres are critical for successful treatment because behavior during the finishing process is determined by both structure and surface properties. The fine structure of natural cellulose fibres i.e. cotton, is different from the regular viscose, modal and new types of regenerated cellulose fibres i.e. lyocell, which are clarified by different hydrophilic/hydrophobic character of fibres and different adsorption properties. Tensiometry, seldom used in fibre characterization was used to obtain the differences in the adsorption properties of different cellulose fibres. The surface tension, contact angle and adsorption were measured, and then compared with various methods for determining water adsorption. Currently some additional methods especially sensitive to surface properties (electrokinetic properties of fibres) are being applied in order to characterize the adsorption character and reactivity of the fibre surfaces. The streaming potential was measured due to the fact that the interaction properties are strongly influenced by electric charges on the surface, and from these values the zeta potential (ζ) was calculated as a function of the pH and the surfactant concentration in the liquid phase. As with the results of fibre reactivity and adsorption properties obtained by conventional methods, the electrokinetic character of the materials and their adsorption ability determined using the tensiometry also show the same phenomena. The natural fibres have the smaller hydrophilic character and they are less reactive than the regenerated ones, so the ζ_max of cotton is the highest and the contact angle ϕ the greatest [1, 2, 3] Electronic Publication     

Composition of the beef wholesale rib

Wholesale ribs (n = 40) were dissected to determine composition from anterior to posterior end. There were much greater differences in tissue amounts from different anatomical locations within the wholesale rib than between wholesale ribs from carcasses of different USDA yield grades. Kernel fat (seam fat between the longissimus and spinalis dorsi muscles) was found in considerably higher amounts in the 7th, 8th, and 9th rib bone sections. Removal of the lip from IMPS 112A decreased the separable fat content of ribeyes by approximately 46%. This large decrease in fat could make the ribeye more appealing to today's consumer.     

Satellite-to-satellite tracking and satellite gravity gradiometry (Advanced techniques for high-resolution geopotential field determination)

The purpose of satellite-to-satellite tracking (SST) and/or satellite gravity gradiometry (SGG) is to determine the gravitational field on and outside the Earth's surface from given gradients of the gravitational potential and/or the gravitational field at satellite altitude. In this paper both satellite techniques are analysed and characterized from a mathematical point of view. Uniqueness results are formulated. The justification is given for approximating the external gravitational field by finite linear combination of certain gradient fields (for example, gradient fields of single-poles or multi-poles) consistent to a given set of SGG and/or SST data. A strategy of modelling the gravitational field from satellite data within a multiscale concept is described; illustrations based on the EGM96 model are given.     

Filtrationsmembranen und spezifische Adsorber auf der Basis von maßgeschneiderten selbst-organiserenden Blockcopolymeren

Due to their ability to form self-assembled structures, block copolymers offer various possibilities for material separation. Flat and hollow filament membranes with regularly arranged pores of the same diameter and high pore number density can be produced from self-assembling block copolymers. The pore sizes and functionalities of these membranes and thus their application possibilities in the material separation can be adjusted in different ways, whereby the setting of these parameters on finished membrane structures is particularly interesting. Furthermore, tailor-made amphiphilic block copolymers can be used for the specific extraction of substances from aqueous (hydrophilic) solutions to organic (hydrophobic) solutions.     

Influence of Skydrol immersion at elevated temperatures on the thermo-mechanical properties of a high-Tg anhydride epoxy resin toughened with a hydroxy-terminated polyester

Currently, the application of composites in aerospace parts exposed to higher temperatures and in aggressive media is still severely limited. To replace metal alloys, alternative resins systems with suitable long-term heat resistance are needed. In this study, the effect of the aviation hydraulic fluid Skydrol on the thermal and mechanical properties of a high-T_g, anhydride-cured epoxy resin in the unmodified and toughened state at elevated temperature is investigated. An aliphatic polyester diol was selected as an intrinsic toughener and its impact on the thermal, mechanical, and aging properties was determined. Experimental characterization of the aging effects is carried out with dynamic-mechanical characterization, infrared spectroscopy, and electron dispersion x-ray spectroscopy. In addition, the fracture toughness and the fatigue crack propagation behavior are determined. Initially, the toughened system shows an improved fracture toughness. Since oxidation is blocked by the Skydrol fluid only thermal degradation takes place as determined by the decrease in glass transition temperature T_g and network density. The thermal degradation leads to a tougher behavior, which is observed in both systems in static and dynamic mode with toughness decreasing with aging time again.     

Micropatterning of Ag and Au nanoparticles by microcontact printing and block copolymer micelles

Micropatterns of gold and silver nanoparticles were successfully obtained by combining microcontact printing and poly(2-vinylpyridine)-block-poly(cyclohexyl metharylate) (P2VP-b-PCHMA) diblock copolymer micelles with metal precursors. The metal ions were incorporated into poly(2-vinylpyridine) blocks and located into the core area of micelles. Then the metal-loaded micellar solutions were used as inks which were spin coated as thin layers onto polydimethylsiloxane stamps and transferred onto the substrates by stamping. Different morphologies of micellar aggregates were formed on the substrates depending on the stamp morphologies, and single layers of nanoparticles in the micropattern were obtained by the reducing process.