Outreach Programs

Education Programs Technology Outreach Program International Programs Distinguished Lecturer Series International Center for Materials Research MRL Diversity Fellowship MRL Travel Fellowship

Intern: Will Gans, Mechanical Engineering, UC Berkley Mentor: Vladimir Tolpygo Faculty Supervisor: David Clarke Department: Materials

Development of a Method for Producing Defined Surface Roughness of an Fe-Cr-Al-Y Substrate.

Different methods for introducing a controlled surface roughness onto a Fe-Cr-Al-Y sample surface were explored. Roughness with a wavelength of l = 20-100 mm and up to 10 mm amplitude were sought. Ion milling and chemical etching were both used as means of material removal. Physically attached grids of different size and holographically-etched photoresist were used to selectively cover portions of the substrate surface during ion milling. Alternatively, niobium and silicon dioxide, deposited onto the substrate through a grid mask were used to protect the substrate during chemical etching. A maximum of 2-micron roughness was achieved using ion milling, while 4-micron roughness was achieved using chemical etching.
Turbine Engines are an essential component of aircraft and power generation industries. The efficiency of the gas turbine is directly related to the temperature in the combustion chamber. Service temperatures for aircraft or power-generation turbine combustion chambers can reach up to 1500C. However, an increase in temperature of the metal components (in particular, the turbine blades) results in a degradation of their mechanical properties. In order to prolong the life and preserve the desired mechanical performance of the Ni-based superalloys, which comprise the functional part of the chamber, a Thermal Barrier Coating (TBC) is applied. Prior to TBC deposition, the superalloy surface is coated with aluminum-containing alloy, called a bond coat (BC) [1]. The bond coat increases adhesion of the TBC and corrosion (oxidation) resistance of the superalloy. During service, a thermally grown aluminum oxide (TGO) forms between the bond coat and the TBC. The properties and performance of this oxide layer largely determine the life of the whole component.

Figure 1 shows a simple schematic of gene therapy, where we take cationic lipids, used as the nonviral vector, to introduce the foreign DNA into a cell. Once the CL/DNA complex has passed through the cellular membrane, we hope that the DNA is broken free from the complex and released in the cell. The DNA will then pass through the nuclear membrane into the nucleus, which will eventually be transcribed into RNA and then expressed into protein. My part of the project was primarily focused on the process of transfection alone (points 1-2). Although I briefly learned the techniques to study the expression of DNA during the summer, I focused on studying the images taken from transfection. Another intern in the research group focused on how much protein was expressed from foreign DNA (points 3-4).

Return to the RISE 2000 project list