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250438

Research outputs

As an application-oriented research organisation, Fraunhofer aims to conduct highly innovative and solution-oriented research - for the benefit of society and to strengthen the German and European economy.

13130

Projects

Fraunhofer is tackling the current challenges facing industry head on. By pooling their expertise and involving industrial partners at an early stage, the Fraunhofer Institutes involved in the projects aim to turn original scientific ideas into marketable products as quickly as possible.

9114

Researchers

Scientific achievement and practical relevance are not opposites - at Fraunhofer they are mutually dependent. Thanks to the close organisational links between Fraunhofer Institutes and universities, science at Fraunhofer is conducted at an internationally first-class level.

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Institutes

The Fraunhofer-Gesellschaft is the leading organisation for applied research in Europe. Institutes and research facilities work under its umbrella at various locations throughout Germany.

Recent Additions

  • Publication
    Formation of bromoform in irradiated titanium dioxide suspensions with varying photocatalyst, dissolved organic carbon and bromide concentrations
    ( 2009)
    Tercero Espinoza, Luis Alberto
    ;
    Rembor, Maximilian
    ;
    Matesanz, Clara A.
    ;
    Heidt, Axel
    ;
    Frimmel, Fritz H.
    We report the formation of bromoform in TiO(2) suspensions (P25) under simulated solar UV irradiation at different concentrations of photocatalyst (0.5-1.5 g L(-1)) as well as initial concentrations of bromide ions (1-3 mg L(-1)) and 2,4-dihydroxybenzoic acid (2-10 mg L(-1)). The extent of bromoform formation (3-17 mu g L(-1)) was most strongly affected by the amount of photocatalyst present and by the initial bromide concentration, increasing either of which leads to increased bromoform formation. Important interaction effects were observed when simultaneously increasing the concentrations of TiO(2) and bromide as well as of bromide and DHBA. The time it takes for bromoform. to appear in measurable concentrations in the irradiated TiO(2) suspensions was between 10 and 90 min and most strongly depended on the initial concentration of dissolved organic carbon present in the suspensions, along with the amount of photocatalyst, also in interaction with the initial bromide concentration.
  • Publication
    Influence of dissolved organic carbon source, photocatalyst identity and copper(II) ions on the formation of bromoform in irradiated titanium dioxide suspensions
    ( 2010)
    Tercero Espinoza, Luis Alberto
    ;
    Malerba, Raquel R.
    ;
    Frimmel, Fritz H.
    We report the irradiation of titanium dioxide suspensions (Hombikat UV100 and P25) under different conditions regarding the source of dissolved organic carbon (2,4-dihydroxybenzoic acid and brown water from a bog lake), and with and without added copper(II) ions. In contrast to P25 suspensions, we found no significant bromoform formation in Hombikat UV100 suspensions, likely because bromoform is degraded faster with Hombikat UV100 than with P25, preventing accumulation. In the case of P25 suspensions, the presence of 10 mu M of added Cu2+ significantly inhibited bromoform formation. Bromoform was the only measurable trihalomethane (THM), even in the presence of 250 mg L-1 chloride ions. The concentrations of formed THM were below the limits for drinking water under all investigated experimental conditions.
  • Publication
    Economic impact of the introduction of the German HGV toll system
    ( 2007) ;
    Schaffer, Axel
    After a long period of political debate and technological difficulties, the German heavy goods vehicle ( HGV) toll system was finally put into operation in January 2005. This paper is divided into two main parts. The first section discusses the German HGV toll in detail, with a focus on fee calculation. This is followed by an analysis of the macro-economic impact of the toll. Based on an input-output model for the German economy involving 70 distinct industries, undesirable potential price increases are considered along with potential positive employment effects which can be expected if the toll revenue re-enters the economy.

Most viewed

  • Publication
    Electronic Fuse
    ( 2002)
    Licht, U.
  • Publication
    Prozeßketten: ein Modell für die Logistik
    ( 1996)
    Kuhn, A.
    Die Logistik muß Material- und Informationsflüsse beherrschen. Dazu steuert sie den Fluß von Objekten (z.B. Produkte, Paletten oder Aufträge) durch die Einzelprozesse der Prozeßketten. Alle diese Prozesse nehmen spezifische Veränderungen an den Objekten vor: bearbeiten, transportieren, puffern, prüfen. Zwischen diesen Prozessen werden Informationen (Daten) und Material ausgetauscht. Die Funktionalität dieser Austauschprozesse in der Prozeßkette bestimmt die Qualität der Logistik nachhaltig. Jeder Prozeß hat also sowohl als Kunde als auch als Lieferant eine Fülle von Austauschprozessen zu beherrschen, die man als Geschäftsprozeß bezeichnet. Ein Logistik-Modell, welches die Qualität von Prozeßketten bewertet und Verbesserungspotentiale aufdecken will, muß diese Kunden-Lieferanten-Beziehungen beschreiben. Ein Modell, dessen Strukturen sich in immer feineren Ausprägungen wiederholen, nennt man selbstähnlich. Die Strukturelemente der Prozesse, die sich auf immer kleineren Skalen wiederholen , sind: - Quellen, - Senken, - "interne" Prozeßketten (Prozesse), - Lenkungshierchie, - Ressourcen. Diese Strukturelemente kann man verändern, wenn es darum geht, die Logistikqualität eines Prozesses anzupassen.
  • Publication
    Konzeption eines System Dynamics Modells zur strategischen Planung von Closed-Loop Supply Chains - dargestellt am Beispiel der Ersatzteilversorgung
    ( 2005)
    Spengler, T.
    ;
    Schröter, M.
    Aufgrund neuer rechtlicher Regelungen zur Produktverantwortung kommt der frühzeitigen Entwicklung produktspezifischer Rücknahme- und Recyclingstrategien für betroffene Unternehmen zunehmend eine große Bedeutung zu. Zur Umsetzung hochwertiger Recyclingkreisläufe auf Produkt- und Komponentenebene sind vermehrt Closed-Loop Supply Chains, welche um Demontage- und Recyclingunternehmen erweiterte Supply Chains darstellen, zu gestalten. Im Mittelpunkt des vorliegenden Beitrags steht die strategische Closed-Loop Supply Chains zur Wiederverwertung von Produktkomponenten zur Sicherstellung der Ersatzteilversorgung in der Nachserie. Zur Entscheidungsunterstützung wird ein generisches System Dynamics Modell entwickelt und im Rahmen einer Fallstudie angewendet, mit dem es möglich ist, alternative Strategien und mögliche Szenarien zur Gestaltung einer entsprechenden Closed-Loop Supply Chain zu simulieren und betriebswirtschaftlich zu nutzen.
  • Publication
    Approximations made evaluating the residual electrical dc resistivity of disordered alloys
    ( 1994)
    Banhart, J.
    ;
    Ebert, H.
    ;
    Voitländer, J.
    ;
    Weinberger, P.
    The residual electrical dc resistivity of the transition-metal-alloy system Cu-Pt is evaluated by making use of the relativistic version of the Korringa-Kohn-Rostoker-coherent potential approximation and the one-electron Kubo-Greenwood formula for disordered systems. Starting from the results of a previous calculation the influence of truncation of the angular momentum expansion, the effects of self-consistency of the alloy potential, the importance of vertex corrections, and the difference between the nonrelativistic and the relativistic current operator are examined.