23 research outputs found
An Oil-Based Lubrication System Based on Nanoparticular TiO2 with Superior Friction and Wear Properties
Bogunovic L, Zünkeler S, Tönsing K, Anselmetti D. An Oil-Based Lubrication System Based on Nanoparticular TiO2 with Superior Friction and Wear Properties. Tribology Letters. 2015;29(2): 59.We evaluated the performance of five different commercially available nanoparticle classes as additives for an oil-based lubrication system. While the silicon dioxide particles Aerosil® 300, RY300, and R972V tended to increase wear and friction in our 100Cr6 versus cast iron disc–disc contact, Aeroxide® P 25 and especially T 805 TiO2 nanoparticles showed superior anti-wear and anti-friction properties. The underlying tribological mechanism was investigated with optical microscopy, helium ion microscopy, and X-ray photoelectron spectroscopy. Subsequently, we formulated a stable lubrication system based on the best performing T 805 particles. Here, the base oil is a highly purified paraffin oil which was supplemented with 1 wt% T 805 TiO2 particles, 1 wt% Estisol® 242 or 1 wt% oleic acid, 0.15 wt% oleylamine, and 0.15 wt% Pluronic® RPE 2520. Superior lubrication and anti-wear properties of this formulation were demonstrated in 4-h test runs with a normal force of F N = 2.5 kN and a sliding velocity of 0.15 m/s in our disc–disc contact. Wear was significantly reduced along with a nearly 12-fold reduction in the friction coefficient, compared to the base oil (μftobase=0.155vs.μftoT805≈0.01). Using 100Cr6 disc–ball contacts, we additionally analyzed the properties of our lubrication system in the border friction regime under higher loads (F N = 0.5 kN) in 2-h runs. In particular, on the discs with lower engagement ratio, chemo-tribological protective layers were built, which protected the parts very well against wear
Rubidium and potassium levels are altered in Alzheimer’s disease brain and blood but not in cerebrospinal fluid
Tribologische Untersuchungen an Nanopartikel-additivierten Schmierstoffen
Zünkeler S. Tribologische Untersuchungen an Nanopartikel-additivierten Schmierstoffen. Bielefeld: Universität Bielefeld; 2013.Durch die wissenschaftlichen Erfolge der Nanotechnologie werden heute zahlreiche Nanopartikel
großindustriell hergestellt und somit für viele Anwendungen in der Industrie
interessant. Einsatzgebiete ergeben sich in den Bereichen: Pharmazie, Elektronik,
neue Materialien, Biotechnologie, Maschinenbau, Umwelttechnik und der Lebensmitteltechnologie
[11, 55]. Neue Möglichkeiten bieten Nanopartikel jedoch auch in der
Schmierungstechnik. In dieser Arbeit wurde ein Grundöl mit verschiedenen Nanopartikeln
additiviert und der Einfluss auf das Reibungs- und Verschleißverhalten untersucht.
Dabei hat sich gezeigt, dass insbesondere Titandioxid-Nanopartikel exzellente,
tribologische Eigenschaften aufweisen.
Zur Untersuchung der Schmierstoffe wurde ein Rotationstribometer durch die Konstruktion
eines Scheibe-Scheibe-Halters an die gestellten Anforderungen angepasst.
So konnten neben Tests unter extremen Lastbedingungen (Punktkontakt) auch die
Gleitreibungseigenschaften eines flächigen Kontakts im Gebiet der Mischreibung untersucht
werden
Next Generation Biobanking - From Biorepository To Data Integration Center
Introduction/ Background
Biobanks and their operators are gaining popularity. However, they face a range of growing challenges. Many of these biobanks used to be smaller and midsized collections of data and samples, but are now being developed into centralized networks within clinics and consortia. These large biobanks require the integration of as many sources of information as possible, including imaging data in addition to any relevant structured data. This is especially the case in the field of virtual microscopy. Data collection is increasingly being orchestrated by workflow based systems and must eventually be incorporated entirely into rule based IT-processes.
Aims
In order to achieve this goal, the Charité University Medicine Berlin, VMscope GmbH, and Kairos GmbH formed a consortium in the framework of the joint project, “Biobanking 3.0”, which is funded by the German Federal Ministry for Education and Research (BMBF). Furthermore, after this successful project, a second KMU funded project called POST (Patient-centric Open Multi Center Study Tool) will begin in the autumn of 2015 to expand the data integration to pathology information systems in a standardized manner.
Methods
One of the project goals is to use an IT-platform with an integrated workflow-engine to orchestrate all necessary processes and document all findings. Defined SOPs during sample extraction and information acquisition can be executed, and all result data can be made available to local research groups as well as project partners.
Results
Thus, the platform pursues the research approach of personalized medicine, which requires exact controlling of therapy cycles in a logical and chronological order