Vergleich der umweltrelevanten Faktoren von Holzfurnierlagenverbundwerkstoffen (WVC – Wood Veneer Composite) und metallischen Werkstoffen am Praxisbeispiel eines Skidfördersystems

Für eine Beurteilung von Produkten bzw. Produktsystemen im Maschinenbau spielen neben technischen Kennwerten immer mehr die Umweltauswirkungen der Systeme eine wichtige Rolle. Diese Anforderungen haben die Nachfrage für nachhaltige und umweltfreundliche Konstruktionswerkstoffe im Maschinenbau erhöht. Eine Möglichkeit für solche ökologisch vorteilhaften Werkstoffe stellen ausgewählte Holzwerkstoffe dar. Mit diesen Holzwerkstoffen sollen technische Produkte entwickelt werden, welche den Unternehmen die Möglichkeit eröffnet, ihren unternehmerischen Beitrag zur Nachhaltigkeit zu steigern und wirtschaftliche Vorteile zu erzielen. Durch diesen Ansatz ist ein gewisses Maß an Ressourcen- und Energieeffizienz verbunden, dass sich kurzfristig und / oder langfristig wirtschaftlich lohnt. Ein damit verbundener gesellschaftlicher Imagegewinn erzeugt einen zusätzlichen Nutzen. Als sogenannte GLP (Green Logistics Plant) wird diese Art der Holzkonstruktion gegenwärtig im Bereich der Fördertechnik entwickelt und angewendet. Ein Anwendungsbeispiel innerhalb der GLP stellt das Gestellsystem für einen Skidförderer dar. Um die ökologische Wirkung der Konstruktionswerkstoffe transparent und nachvollziehbar zu untersuchen, werden vordergründig die Kategorien des Treibhauspotenzials und des (Primär-) Energieaufwandes genutzt. Weiterhin werden die Wirkungskategorien Versauerung, Eutrophierung, Sommersmog und Ozonabbau analysiert. Ergänzend zu bestehenden Untersuchungen soll die ökologische Vorteilhaftigkeit von Holzfurnierlagenverbundwerkstoffe (Wood Veneer Composite – WVC), Baustahl, verzinktem Stahl und Aluminiumlegierungen in der Lebensphase Produktion untersucht werden. Anschließend werden die Ergebnisse auf das Gestell eines Skid-Fördersystems aus WVC und Baustahl übertragen.

Clinical outcome of single porcelain-fused-to-zirconium dioxide crowns: a systematic review

STATEMENT OF PROBLEM The increasing demand by patients for esthetic and metal-free restorations has driven the development of ceramic restorations with good esthetic and mechanical stability. Recent clinical studies have investigated the use of zirconium dioxide as a core material for complete crowns and computer-aided-design/computer-aided-manufacturing fabricated restorations. PURPOSE The aim of this systematic review was to evaluate the clinical survival rates of porcelain-fused-to-zirconia (PFZ) single crowns on anterior and posterior teeth and to compare them with metal ceramic (MC) crowns. MATERIAL AND METHODS A systematic search was conducted with PubMed and manual research to identify literature written in English that refers to in vivo studies published from January 1, 1950 through July 1, 2011. Clinical trials that evaluated PFZ and MC single crowns on natural teeth were selected for further analysis. Titles and/or abstracts of articles identified through the electronic searches were reviewed and evaluated for appropriateness. In addition, a hand search of relevant dental journals was peformed, and reference lists of culled articles were screened to identify publications. RESULTS The search resulted in a total of 488 initial matches. Nineteen studies with a total of 3621 crowns met the inclusion criteria. The survival rates of PFZ crowns (total 300) ranged from 92.7% to 100% for a follow-up time of 24 to 39 months, whereas those of MC crowns (total 3321) ranged from 70% to 100% for a follow-up time of 12 to 298 months. Studies that reported long-term results were found only for the MC crown group. CONCLUSIONS The scientific clinical data available to compare PFZ and MC crowns are limited. The survival rates may well be influenced by the selection and appropriate use of the veneering ceramic, and, therefore, additional prospective long-term clinical trials are necessary to draw reliable conclusions.

Temperature and acidification variability reduce physiological performance in the intertidal zone porcelain crab Petrolisthes//cinctipes

We show here that increased variability of temperature and pH synergistically negatively affects the energetics of intertidal zone crabs. Under future climate scenarios, coastal ecosystems are projected to have increased extremes of low tide-associated thermal stress and ocean acidification-associated low pH, the individual or interactive effects of which have yet to be determined. To characterize energetic consequences of exposure to increased variability of pH and temperature, we exposed porcelain crabs, Petrolisthes cinctipes, to conditions that simulated current and future intertidal zone thermal and pH environments. During the daily low tide, specimens were exposed to no, moderate or extreme heating, and during the daily high tide experienced no, moderate or extreme acidification. Respiration rate and cardiac thermal limits were assessed following 2.5 weeks of acclimation. Thermal variation had a larger overall effect than pH variation, though there was an interactive effect between the two environmental drivers. Under the most extreme temperature and pH combination, respiration rate decreased while heat tolerance increased, indicating a smaller overall aerobic energy budget (i.e. a reduced O2 consumption rate) of which a larger portion is devoted to basal maintenance (i.e. greater thermal tolerance indicating induction of the cellular stress response). These results suggest the potential for negative long-term ecological consequences for intertidal ectotherms exposed to increased extremes in pH and temperature due to reduced energy for behavior and reproduction.

Ventilated Stone Veneer: Mechanical Behaviour, Calculation Methodologies, Major Pathologies and Existing Tests

The increase of building pathologies related to the use of stone materials and the use of ventilated stone veneers, requires the reformulation of design concepts in building façades and also the reformulation of the architectural project. The aim of this paper is to identify, analyze and evaluate synthetically building pathologies in stone ventilated façades in order to obtain the main technical conditions to be considered in the architectural design, by interpreting its mechanical behavior and capabilities to prevent such pathologies and to ensure the proper features during the building lifetime. The methodology is based on both laboratory stone tests and in situ tests about construction systems, by analyzing physical and mechanical behavior of the outer layer in relation to other building requirements. The results imply the need of proper sizing, specific quality control and practical application of calculation methods, to control high concentration pressures in ventilated façades by reaching appropriate project solutions. In conclusion, the research about different pathologies of stone ventilated façades, the study of their mechanical behavior, their anchorage and their connection with their constructive aspects, will help to improve the construction quality of the stone ventilated façade in buildings and to enhance the use of natural stone in modern architecture.

Under the veneer of decentralisation. Ukraine's modernisation efforts stall due to lack of local government reform. OSW Commentary No. 102, 2013-02-12

President Viktor Yanukovych and his Party of Regions have been repeating the pledge to decentralise power in Ukraine and to give local government a greater decision-making role ever since the party appeared on the Ukrainian political scene. The implementation of this reform is crucial both for the economic recovery of Ukraine’s regions and the overall modernisation efforts of the Ukrainian state. At present relations between central government and the regions are regulated by Soviet-era legislation that fails to address the modern-day challenges facing Ukraine. The political elite in the country, including the opposition, appear to have reached consensus on the importance of the decentralisation reform. The first attempts to implement changes in this area were made in the late 1990s, followed by a comprehensive reform programme developed between 2007 and 2009 by Yulia Tymoshenko’s government. In 2012, the Constitutional Assembly under the President of Ukraine appointed a team of experts who drafted a document detailing the reform of local government and the territorial organisation of power1. The document envisages the implementation of what effectively are two major reforms: (1) an administrative-territorial reform, which would help consolidate the fragmented administrative structure, creating larger and more economically self-sufficient administrative units, and (2) local government reform, focusing on creating clearly defined powers for local authorities with a view to securing government funding for specific tasks delegated from central government. Nonetheless, despite these measures, and in spite of the rhetoric coming from President Yanukovych and other members of the Party of Regions, it seems unlikely that the reform will be implemented in the foreseeable future. A series of concrete political decisions taken by the president over the past three years indicate that Yanukovych has not abandoned his plan to build a highly centralised political system. This in turn limits the capacity to govern of local authorities and further restricts the sources of funding for Ukraine’s regions. This apparent resistance to change stems from the fact that by implementing the proposed reforms, the president and his political allies would be forced to relinquish much of their control over the political processes taking place in the country and would have to free up the distribution of budgetary resources between Kyiv and the regions. The implementation of the reform within the specified timeframe (i.e. by 2015) is also unlikely due to the upcoming presidential election and the deteriorating economic situation in Ukraine. Without a comprehensive reform of local government, however, Ukraine will be unable to undertake effective modernisation measures, which are key for the socio-economic development of the country’s regions.

Handbook to the collection of British pottery and porcelain, in the Museum of Practical Geology.

Mode of access: Internet.

Important XVIII century American furniture, rare tall-case banjo & shelf clocks, early American silver and glass, old English porcelain, glass paperweights, primitive & other American paintings, from the collection of Maurice Rubin, sold by his order, public auction sale, Saturday, Oct. 9 [1954]

Mode of access: Internet.

Chinese porcelain and hard stones,

"This edition is limited to one thousand copies, of which this is ... no. three hundred and twenty-five."

The old china book, including Staffordshire, Wedgwood, lustre, and other English pottery and porcelain,

"List of views, American, English & miscellaneous. By English potters": p. [254]-283.

Uranium in dental porcelain /

Item 498-B-4

A picture book of German porcelain figures.

Mode of access: Internet.

The ceramic art of Great Britain from pre-historic times down to the present day : being a history of the ancient and modern pottery and porcelain works of the kingdom and of their productions of every class /

Mode of access: Internet.

Inventory of the collection of pictures, miniatures, decorative furniture, porcelain, objects of art, books, &c. /

Cover title: The Jones collection.