Credit: DTRA.
We received the following from the DOD Basic and Applied Sciences Directorate, Defense Threat Reduction Agency:
DTRA’s mission is to safeguard America and its allies from Weapons of Mass Destruction. The university-centric DTRA Basic Research Program supports basic science research within five Thrust Areas of relevance to DTRA, an essential ingredient of which is materials science:
1. Science of WMD Sensing and Recognition.
2. Cognitive and Information Science.
3. Science for Protection from WMD.
4. Science to Defeat WMD.
5. Science to Secure WMD.
Science of WMD Sensing seeks materials for use in the detection and identification of nuclear and radiological material and forensics. Radiation detection materials impact the performance of all known radiation sensors, whether they are networked, stand-alone, stationary, or mobile. Advances in radiological detection materials could improve the abilities of detectors to detect, classify, and identify nuclear and radiological materials of concern. Problems in crystal growth, candidate material identification, and performance prediction recur for all classification of detector materials such as scintillation and semiconductor materials, to include plastic, organic, glass, and nanocrystal materials, as well as the more traditional crystalline materials. Further, nano-sized particles that emit spectral signatures in the presence of ionizing radiation when incorporated in other widely used materials or widely used objects, would assist in locating and securing such materials. Nano-indicators could be utilized to find or tag and track special nuclear materials, and other radioactive materials that could be used in a radiological dispersal device.
In addition, WMD Sensing Sciences seek novel sensing methods by using or creating secondary effects caused by radiological materials interacting with the surrounding environment and shielding materials. To this end, knowledge of physical or chemical interactions of radiological materials with explosives, high-Z metals, and other materials that may result in novel signatures for sensing fissile materials, is desired.
Science for WMD Protection includes seeking to protect new materials that could be used in future counter-WMD systems, particularly radiation hardening of systems. “Moore’s Law” has observed that the number of transistors that can be reasonably placed on a single integrated circuit has doubled approximately every two years. This trend has continued for more than half a century, but there has been concern that this trend will run out of steam with current complementary metal-oxide-semiconductor technology within a few years.
One approach to dealing with the need to develop new technology for increasing electronic IC device capability and performance has been to investigate completely new systems, such as compound semiconductors, hetero-structure field effect concepts, and non-silicon high mobility transistor circuits. DTRA is interested in the radiation and electro-magnetic pulse effects related to these new prospective technologies with a view of drastically reducing shielding requirements, enhancing robustness and recovery, and mitigating and compensating for short- and long-term radiation effects.
Science to Defeat WMD seeks materials research for, and material modeling of, counter-WMD weapons. Energetic materials with fast energy release have long been utilized in rockets and weapons. Energetic materials react to yield heat and gaseous reaction products, resulting in high temperatures and high pressures. Inherently, materials with fast energy release are metastable, often with positive heats of formation, making them extremely sensitive to friction, heat, etc. Therefore, future energetic materials must not only have higher energy density with high release rates, but also controllable energy release or insensitivity to external stimuli.
As seen by efforts over the past 50+ years, synthesis approaches within traditional C, H, O, N chemistry will likely yield only modest increases in energy density. In additional, traditional synthesis approaches can be cost-prohibitive and labor intensive, as certain intermediate compounds are notoriously difficult to produce. Nontraditional approaches using novel types of materials and process hold more promise to achieve much higher energy densities. Examples include metal and/or organic ingredients that are polymerized in block copolymer-like configurations, or prepared in composites of stacked ultrathin single-crystal sheets, or self-assembled into larger three-dimensional fully dense crystalline composites, etc. Novel processes may include the use of cellular “nanofactories” to provide for selective placement of functional groups, streamlining the production of traditional and designer energetic materials. Future energetics may also be designed and built similar to metamaterials, with various fuel-oxidizer composite components that have the necessary shock-wave refracting indices to produce and focus energy.
Further, because of the fast kinetics of energetic material reactions, the initiation, reaction to detonation or combustion, gas production and associated turbulence, etc. are still not well characterized with the necessary time resolution, at the appropriate and high-pressure high-temperature conditions. Future energetic materials need experimental and numerical investigation so that we can model and simulate their performance with purely science-based models, and thereby design materials with reproducible high energy density and controllable fast energy release.
Science to Secure WMD seeks materials solutions to securing WMD and verifying WMD treaties (including potential future agreements and treaties). For example, the treaty language within the Comprehensive Nuclear-Test-Ban Treaty includes the right to request an on-site inspection of an event that indicates a nuclear explosion in violation of the treaty. A significant challenge to conducting a successful on-site inspection of a suspected underground event is to understand the source activation products likely to be encountered by an inspection team. Rapid and efficient chemical fractionation of ground samples collected during an on-site inspection represents a significant challenge in the post-detonation environment (e.g., composition is variable and may include sand, hard rock, gravel, etc.).
Well contained underground explosions have released radioxenon isotopes, but few, if any, of the other unique signatures or activation products that may be expected. The development of robust chemical fractionation models along with transport in the underground environment will advance the knowledge base that is currently not well defined and poorly understood for on-site inspections to detect clandestine underground nuclear explosions.
In addition to supporting traditional materials synthesis methods, DTRA encourages innovative approaches to developing both conventional and designer materials using cost-effective and environmentally-friendly methodologies. Current DTRA materials research interests for countering weapons of mass destruction are specified in topics listed in the “Basic Research for Combating Weapons of Mass Destruction” Broad Agency Announcement published in www.grants.gov. More information about the program including open solicitations and thrust areas can be found at www.dtrasubmission.net/portal.