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environment
Tool for Rapid Identification of TCE in Plants
Plant uptake of TCE from contaminated groundwater is a well-known phenomenon. During the photosynthesis process, plants metabolize the TCE into a byproduct called trichloroacetic acid (TCAA). TCAA has been found to be a good indicator (or surrogate) molecule for the presence of TCE because it is more stable than TCE in plants. The hyperspectral estimator is being designed to detect TCAA. The method uses a white light that is directed at the surface of a plant's leaf. The interaction between the light and the leaf produces spectral signatures that are captured using a detector. A processor that will be coupled to the detector will compare these signatures to a library/database of signatures known to be indicators of the presence of TCAA (and thus TCE). The figure below on the left shows hyperspectral images captured using the method for leaves dosed with TCE over various time periods. These images are examples of response signatures that will eventually be built into the device's reference library/database. Proof-of-concept testing has shown that the hyperspectral estimator is capable of estimating the presence/absence of TCE in plant leaves with an accuracy of 80%. Efforts are now underway to further improve the accuracy of this method and to prototype the technology. The figure below on the right shows a diagram of the planned device.
Instrumentation
Robotic Inspection System for Fluid Infrastructures
The Robotic Inspection System improves the inspection of deep sea structures such as offshore storage cells/tanks, pipelines, and other subsea exploration applications. Generally, oil platforms are comprised of pipelines and/or subsea storage cells. These storage cells not only provide a stable base for the platform, they provide intermediate storage and separation capability for oil. Surveying these structures to examine the contents is often required when the platforms are being decommissioned. The Robotic Inspection System provides a device and method for imaging the inside of the cells, which includes hardware and software components. The device is able to move through interconnected pipes, even making 90 degree turns with minimal power. The Robotic Inspection System is able to display 3-dimentional range data from 2-dimensional information. This inspection method and device could significantly reduce the cost of decommissioning cells. The device has the capability to map interior volume, interrogate integrity of cell fill lines, display real-time video and sonar, and with future development possibly sample sediment or oil.
information technology and software
Interactive Diagnostic Modeling Evaluator
The i-DME is a computer-user interactive procedure for repairing the system model through its abstract representation, diagnostic matrix (D-matrix) and then translating the changes back to the system model. The system model is a schematic representation of faults, tests, and their relationship in terms of nodes and arcs. D-matrix is derived from the system models propagation paths as the relationships between faults and tests. When the relation exists between fault and test, it is represented as 1 in the D-matrix. To repair the D-matrix and wrapper/test logic by playing back a sequence of nominal and failure scenarios (given), the user sets the performance criteria and accepts/declines the proposed repairs. During D-matrix repair, the interactive procedure includes conditions ranging from modifying 0s and 1s in the matrix, adding/removing the rows (failure sources) columns (tests), or modifying test/wrapper logic used to determine test results. The translation of changes to the system model is done via a process which maps each portion of the D-matrix model to the corresponding locations in the system model. Since the mapping back to the system model is non-unique, more than one candidate system model repair can be suggested. In addition to supporting the modification, it provides a trace for each modification such that a rational basis for each decision can be verified.
instrumentation
Data Transfer for Multiple Sensor Networks
High-temperature sensors have been used in silicon carbide electronic oscillator circuits. The frequency of the oscillator changes as a function of changes in the sensor's parameters, such as pressure. This change is analogous to changes in the pitch of a person's voice. The output of this oscillator, and many others may be superimposed onto a single medium. This medium may be the power lines supplying current to the sensors, a third wire dedicated to data transmission, the airwaves through radio transmission, or an optical or other medium. However, with nothing to distinguish the identities of each source, this system is useless. Using frequency dividers and linear feedback shift registers, comprised of flip flops and combinatorial logic gates connected to each oscillator, unique bit stream codes may be generated. These unique codes are used to amplitude modulate the output of the sensor (both amplitude shift keying and on-off keying are applicable). By using a dividend of the oscillator frequency to generate the code, a constant a priori number of oscillator cycles will define each bit. At the receiver, a detected frequency will have associated with it a stored code pattern. Thus, a detected frequency will have a unique modulation pattern or "voice," disassociating it from noise and from other transmitting sensors. These codes may be pseudorandom binary sequences (PRBS), ASCII characters, gold codes, etc. The detected code length and frequency are measured, offering intelligent data transfer.
This is an early-stage technology requiring additional development. Glenn welcomes co-development opportunities.
materials and coatings
Molecular Adsorber Coating (MAC)
MAC is a zeolite based coating that captures and traps molecules in its microscopically porous structure. This microscopic nano-textured structure, consisting of large open pores or cavities, within a crystal- like structure, provides a large surface area to mass ratio that maximizes available trapping efficiency. MAC is a durable coating that is applied through spray application.
These sprayable coatings eliminate the major drawbacks of puck type adsorbers (weight, size, and mounting hardware requirements), resulting in cost savings, mass savings, easier utilization, greater adsorber surface area, more flexibility, and higher efficiency.
This coating works in air, as well as vacuum systems, depending on the application. There is potential for ground based spin-off applications of this coating, particularly in areas where contaminants and volatile compounds need to be collected and contained. Example industries include: pharmaceutical production, the food industry, electronics manufacturing (circuit boards and wafers), laser manufacturing, vacuum systems, chemical processing, paint booths, and general gas and water adsorption.
environment
Soil Remediation With Plant-Fungal Combinations
The technology builds on the existing notion that establishment of trees in contaminated soils can be enhanced through the use of ectomycorrhizal (EM) fungi. EM fungi impart resistance to soil extremes such as high temperature, high acidity and heavy metal contamination. This process for soil remediation utilizes specific plant/fungal combinations that are specifically adapted to conditions created by phenolic application to soils, and abilities of ectomycorrhizal fungi to oxidize these compounds. This is done by taking advantage of the ability of native fungi to upregulate enzyme genes in response to changes in host physiological condition and hence enhance natural phenolic oxidation in soils by up to 5-fold. Ectomycorrhizal mediated remediation of phenolic- based contamination through use of specifically adapted ectomycorrhizal fungi and enzymes utilizes the findings that EM fungi in the genera Russula and Piloderma react with positive growth responses to phenolic-based soil contamination. The activities of enzymes that oxidize these compounds increase in activity by 5 fold when the host tree is partially defoliated, which in turn imparts an increase in phenolic oxidation in soils by a similar amount. Defoliation is done by pine needle removal, where 50% of the needles are removed. This process is performed each year on new growth to maintain defoliation.
mechanical and fluid systems
Variable-Aperture Reciprocating Reed (VARR) Valve
The VARR valve has been designed to provide a variable-size aperture that proportionately changes in relation to gas flow demand. When the pressure delta between two chambers is low, the effective aperture cross-sectional area is small, while at high delta pressure the effective aperture cross-sectional area is large. This variable aperture prevents overly restricted gas flow. As shown in the drawing below, gas flow through the VARR valve is not one way. Gas flow can traverse through the device in a back-and-forth reversing flow manner or be used in a single flow direction manner. The contour shapes and spacing can be set to create a linear delta pressure vs. flow rate or other pressure functions not enabled by current standard orifices. Also, the device can be tuned to operate as a flow meter over an extremely large flow range as compared to fixed-orifice meters. As a meter, the device is capable of matching or exceeding the turbine meter ratio of 150:1 without possessing the many mechanical failure modes associated with turbine bearings, blades, and friction, etc.
mechanical and fluid systems
Fluid Structure Coupling Technology
FSC is a passive technology that can operate in different modes to control vibration:
Harmonic absorber mode: The fluid can be leveraged to act like a classic harmonic absorber to control low-frequency vibrations. This mode leverages already existing system mass to decouple a structural resonance from a discrete frequency forcing function or to provide a highly damped dead zone for responses across a frequency range.
Shell mode: The FSC device can couple itself into the shell mode and act as an additional spring in a series, making the entire system appear dynamically softer and reducing the frequency of the shell mode. This ability to control the mode without having to make changes to the primary structure enables the primary structure to retain its load-carrying capability.
Tuned mass damper mode: A small modification to a geometric feature allows the device to act like an optimized, classic tuned mass damper.
materials and coatings
Holey Carbon Allotropes
This invention is for scalable methods that allows preparation of bulk quantities of holey nanocarbons with holes ranging from a few to over 100 nm in diameter. The first method uses metal particles as a catalyst (silver, copper, e.g.) and offers a wider range of hole diameter. The second method is free of catalysts altogether and offers more rapid processing in a single step with minimal product work-up requirements and does not require solvents, catalysts, flammable gases, additional chemical agents, or electrolysis. The process requires only commercially available materials and standard laboratory equipment; and, it is scalable. Properties that can be controlled include: surface area, pore volume, mechanical properties, electrical conductivity, and thermal conductivity.
mechanical and fluid systems
High-Temperature Single Crystal Preloader
For extremely high-temperature sealing applications, Glenn researchers have devised novel methods for fabricating single-crystal preloaders. NASA's high-temperature preloaders consist of investment cast or machined parts that are fabricated in various configurations from single crystal superalloys. Machined preloaders include a variety of spring configurations, compressed axially or radially, fabricated from single crystal slabs. Before machining, the slabs are carefully oriented in a special goniometer using x-diffraction techniques. This helps to maintain proper crystal orientation relative to the machined part and the applied loads. For more complex geometry components which cannot be easily and economically machined, an investment casting approach would be used. Complex preloader geometries include wire coil springs of various configurations. These single crystal preloaders would be designed with the appropriate stiffness for the intended thermal barrier/seal application and placed underneath, or integrated within, the seal/barrier. At extrememly high temperature, the preload device keeps the seal/barrier mated against the opposing surface as the gap between the two surfaces changes, maintaining contact between surfaces and preventing convective heat transfer.