Carsten Schroer

Quantification of the Long-Term Performance of Steels T91 and 316L in Oxygen-Containing Flowing Lead-Bismuth Eutectic at 550°C

The long-term performance of ferritic/martensitic steel T91 and austenitic 316L in oxygen-containing flowing lead-bismuth eutectic at 550°C was investigated by exposing the materials for up to 15,000 h in the CORRIDA loop. The velocity of the liquid-metal flow was 2 m/s and the concentration of dissolved oxygen averaged 1.6 × 10 -6 mass %. The resulting corrosion processes and products were analyzed and quantified using metallographic methods.

Evaluation of liquid tin corrosion on austenitic steels as well as nickel-based alloys and first tests on possible protective surface layers at high temperature

F imaging using doxorubicin (DOX) has been used to image free and encapsulated drug uptake into cells, since intercalation of Dox with DNA leads to a characteristic change. However, suitable nano-conjugates which can able to deliver Dox in a much targeted manner with high specificity in cancer cell are still in extensive search. In this study, we report an anticancer drug delivery system based on doxorubicin-conjugated Fe3O4-GQD based nanoparticles which can act as pH mediated as well as magnetic targeted drug delivery nanocarrier. The as-synthesized nanoparticles consist of uniform spherical size with an average diameter of 35 nm. The drug delivery system demonstrates the ability to release DOX by desorption of drug molecule from GQD surface in mildly acidic environments, mimicking the cancerous cell environment. By functionalizing the surface of the GQD with the iron oxide nanoparticle, the drug releasing phenomenon can be controlled and targeted by the external magnetic effect. The quenching of GQD by DOX due to resonance energy transfer mechanism is applied as optical probe to confirm the DOX conjunction and monitor the release of DOX. The DOX-conjugated nanocarrier exhibits an obvious cytotoxic effect on HELA cancer cells via MTT assay. In addition, the less cytotoxicity of the drug nanocarrier in normal endothelium cell also strongly support the specificity towards the cancer cell which is the most successful aspect of this delivery system. Meanwhile, the successful delivery on magnetic environment of DOX-conjugated nanoparticles was demonstrated through in house made dialysis bag chamber and fluorescence microscopy. Such drug delivery system, which combines pH-triggered and external magnet controlled drug release, has excellent potential applications in cancer therapy and smart imaging. We demonstrate here that, this new class of nanocarrier can fulfill the required specificity and sensitivity as next generation cancer imaging, therapy and sensing system in vitro.Researches on battery materials has considerably increased during the last 30 years due to the huge development of lithium-ion batteries for portable devices (laptops, cellular phones, ...) and more recently with the need to store energy in order optimize its consumption. The next goal is the development of batteries for electric vehicles and their use into the grid. In most of the batteries, the intercalation (deintercalation) of monovalent cations (H, Li, Na) and electrons is the basic electrochemical reaction. The cell voltage is equal to the difference in Fermi level between the two electrodes. If one electrode exhibits a constant voltage it can acts as reference and therefore, the cell voltage reflects all structure modifications which occurs on the material upon intercalation. The change is cell voltage depends on: (i) the electronic band filling, (ii) the change in the band structure due to change in composition, (iii) the modification of the Magdelung energy. For the solid state chemist the studies of the electrochemical reaction using a battery open new possibility to determine phase diagram at RT, but also to synthesize new metastable phases from a precursor made by classical solid state chemistry.

Aspects of Minimizing Steel Corrosion in Liquid Lead-Alloys by Addition of Oxygen

The concept of minimizing steel corrosion in liquid lead-alloys by addition of oxygen strongly depends on the availability of efficient devices for oxygen transfer and reliable oxygen sensors. The accuracy of electrochemical oxygen sensors is analyzed on the basis of theoretical considerations and results from experiments in stagnant lead-bismuth eutectic (LBE). Additionally, the feasibility of gas/liquid oxygen-transfer and the long-term performance of electrochemical sensors in flowing liquid metal are addressed based on operation of the CORRIDA loop, a facility for testing steels in flowing LBE.Copyright