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Synthesis of anticorrosion and antifouling nanoparticles for marine hydrokinetic technology

ACS National Meeting Book of Abstracts

Montoya, Laura; Hernandez-Sanchez, Bernadette A.; Zarick, Cory; Altman, Susan J.; Enos, David E.

Marine Hydrokinetic energy is the production of renewable electricity converted from the kinetic energy of ocean waves, current, tides, or by thermal gradients. Currently an emerging global industry is focused on developing novel technology to harness this sustainable power. These alternative energy devices require advances in anticorrosion and antibiofouling coatings to enhance lifetime and performance. In order to understand the microbial-nanomaterial interaction as well as nanomaterial corrosion process, we have elected to examine a variety of metallic, oxide and phosphate based nanomaterials. The synthesis of these materials using solution precipitation and solovothermal routes along with their full characterization will be presented.

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Ion beam characterization of advanced luminescent materials for application in radiation effects microscopy

Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms

Branson, J.V.; Hattar, K.; Rossi, P.; Vizkelethy, G.; Powell, Cody J.; Hernandez-Sanchez, Bernadette A.; Doyle, Barney L.

The ion photon emission microscope (IPEM) is a technique developed at Sandia National Laboratories (SNL) to study radiation effects in integrated circuits with high energy, heavy ions, such as those produced by the 88" cyclotron at Lawrence Berkeley National Laboratory (LBNL). In this method, an ion-luminescent film is used to produce photons from the point of ion impact. The photons emitted due to an ion impact are imaged on a position-sensitive detector to determine the location of a single event effect (SEE). Due to stringent resolution, intensity, wavelength, decay time, and radiation tolerance demands, an engineered material with very specific properties is required to act as the luminescent film. The requirements for this material are extensive. It must produce a high enough induced luminescent intensity so at least one photon is detected per ion hit. The emission wavelength must match the sensitivity of the detector used, and the luminescent decay time must be short enough to limit accidental coincidences. In addition, the material must be easy to handle and its luminescent properties must be tolerant to radiation damage. Materials studied for this application include plastic scintillators, GaN and GaN/InGaN quantum well structures, and lanthanide-activated ceramic phosphors. Results from characterization studies on these materials will be presented; including photoluminescence, cathodoluminescence, ion beam induced luminescence, luminescent decay times, and radiation damage. Results indicate that the ceramic phosphors are currently proving to be the ideal material for IPEM investigations.

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Direct-write, chemically-prepared temperature insensitive dielectrics

Hernandez-Sanchez, Bernadette A.; Lu, Ping L.; Garino, Terry J.; Sipola, Diana L.; Bell, Nelson S.; Wheeler, Jill S.

Development of high energy density dielectrics with low temperature coefficients of capacitance that are systems integrable are needed for extreme environment, defense and automotive applications. The synthesis of high purity chemically prepared Ca(Zr,Ti)O3 powders is described and has resulted in the lowering of conventional firing temperatures by over 100 C. Direct write aerosol spray deposition techniques have been used to fabricate high quality single layer and multilayer capacitors from these powders. The dielectric constants of the direct write capacitors are equivalent to those of fired bulk ceramics. Our presentation emphasizes the synthesis, phase evolution and microstructure development that has resulted in dielectrics with energy densities in excess of 3 J/cm3 with less than 1% change in dielectric constant over a 200 C temperature range.

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CSI: Dognapping workshop : an outreach experiment designed to produce students that are hooked on science

Hernandez-Sanchez, Bernadette A.; Boyle, Timothy J.; Steele, Leigh A.; Lambert, Timothy N.; Pratt III, Harry D.

The CSI: Dognapping Workshop is a culmination of the more than 65 Sandian staff and intern volunteers dedication to exciting and encouraging the next generation of scientific leaders. This 2 hour workshop used a 'theatrical play' and 'hands on' activities that was fun, exciting and challenging for 3rd-5th graders while meeting science curriculum standards. In addition, new pedagogical methods were developed in order to introduce nanotechnology to the public. Survey analysis indicated that the workshop had an overall improvement and positive impact on helping the students to understand concepts from materials science and chemistry as well as increased our interaction with the K-5 community. Anecdotal analyses showed that this simple exercise will have far reaching impact with the results necessary to maintain the United States as the scientific leader in the world. This experience led to the initiation of over 100 Official Junior Scientists.

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Synthesizing biofunctionalized nanoparticles to image cell signaling pathways

IEEE Transactions on Nanobioscience

Hernandez-Sanchez, Bernadette A.; Boyle, Timothy J.; Lambert, Timothy N.; Daniel-Taylor, Sherrika D.; Oliver, Janet M.; Wilson, Bridget S.; Lidke, Diane S.; Andrews, Nicholas L.

This minireview outlines the synthetic efforts, from our research group, to produce nanomaterials for use as imaging agents to study cell signaling pathways. An overview of our approach to the synthesis and biofunctionalization of metal, semiconductor, and ceramic nanomaterials is presented. The probes investigated include coinage metals, Cd-based, Geo, naturally occurring fluorescent (NOF) minerals, and Ln-based nanoparticles which were synthesized from novel metal alkoxide, amide, and alkyl precursors. We illustrate the applications of some of these materials as imaging probes to detect signaling pathway components and cellular responses to signals (apoptosis and degranulation) in inflammatory and cancer cells. © 2006 IEEE.

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Results 101–125 of 125
Results 101–125 of 125