Sandia LabNews

Symposium focuses on hydrogen storage, radiation monitors, other research areas

Site hears latest news on four key R&D projects, including hydrogen storage

Some late-breaking news came during the latest R&D Focus Symposium showcasing work by researchers at the California site. A nuclear reactor where Sandia is testing a radiation monitor just entered a maintenance shutdown, and Jim Lund (8232) learned during his talk from a team member in the back of the audience that the change was picked up, confirming the monitor works as planned.

Jim described the ongoing work on this antineutrino detector at the San Onofre Nuclear Reactor and also the development of a small neutron generator for use in probing the presence of nearby nuclear materials. He was among four researchers who described their projects during the symposium, the third since the series began about two years ago. Organized by a committee of Distinguished Members of Technical Staff, the series is open to the site as a whole.

Calling the collection of talks "very, very interesting and very exciting," California Laboratory VP Mim John thanked the entire committee for bringing the series to the site.

First up were Jay Keller (8367) and Weifang Luo (8773), describing hydrogen energy research, particularly work at the California site to investigate storage of the volatile gas in powdered metal hydrides, where it is absorbed like water in a sponge. The hydrogen is nonflammable on the hydride bed, and can be drawn off as needed to power a fuel cell to operate a vehicle without creating greenhouse-gas-generating tailpipe emissions.

DOE would like to find a way to store at least 6 weight-percent of hydrogen onboard a vehicle where weight and volume constraints are important. Weifang described a promising compound hydride that may achieve that goal, which is being studied to optimize its operating temperature and pressure.

Jay and Jim Wang (8773) have proposed for Sandia to be a DOE "Center of Excellence" in hydrogen storage, and is also working with Chris Moen (8752) on safety codes and standards, carrying out hydrogen-release studies with SRI.

Next Jim described how a detector the size of a small room installed near the core of the Southern California nuclear reactor is being investigated for its utility in determining whether any fissionable material is being diverted. The monitor detects about one-fourth of the antineutrino flux predicted from the radioactive material that powers the reactor.

Sandia has also developed a meter-tall neutron generator that could interrogate nuclear material by "pinging" it with neutrons that would incite the release of secondary particles that can be detected. The next iteration should be smaller, he says, and a prototype will be tested soon.

Another talk described a new foray for Sandia into a collaboration with the University of Michigan School of Dentistry and Cornell University on engineering the MicroChemLab to detect markers of periodontal disease in saliva. The hand-held device potentially allows better, faster, potentially cheaper analysis of components in liquid samples, and has demonstrated separation of six proteins in less than 30 seconds in a microchannel measuring just 1 millimeter.

Periodontal disease affects more than half of US adults, 20 million to 45 million of them severely, and may be an initiating cofactor in serious systemic illness that costs $5-6 billion annually. The goal is to be able to screen for a bacterial infection, gingivitis, which causes inflammation of the gum that leads to bone loss if unchecked.

Anup Singh (8130), who is leading the project with Victoria VanderNoot (8130), said patients conceivably will be screened during routine appointments by collecting saliva on a strip of paper inserted between the tooth and gum. The saliva would be subjected to an immunoassay on the microchip while the patient waits. Future improvements to the hand-held chemical analysis device might include changing the detection system (which currently employs a light source) to rely on chemiluminescence.

Wrapping up the symposium, Dahv Kliner (8356) talked about his breakthrough in a collaboration with the Naval Research Laboratory to amplify the power in fiber-optic lasers and change the wavelength to usable visible or ultraviolet light.

Dahv said their year-old record still stands of showing the highest levels ever extracted from a fiber light source of peak power, pulse power, and average power.

By selectively bending the fiber, they were able to direct the energy toward a stable beam that has 20 to 30 times the power of a typical fiber laser. The fiber is doped for optical gain, and the strategic coiling selectively eliminates unwanted modes without any loss of efficiency.

A series of three crystals converts the infrared light to visible or ultraviolet, which is particularly useful in the $500 million annual materials-processing market, among other applications. The invention fits in a box measuring 4.5 by 3.5 inches, which is two orders of magnitude less than the competing technology, and can deliver watts or tens of watts of power with no substantial additional breakthrough, Dahv said, commenting, "we’ve really just scraped the surface."