Student Abstracts: Engineering at PNNL

Microsorption Systems for CO2 Capture and Compression.. DUSTIN CALDWELL (Washington State University, Pullman, WA 99163) SCOT RASSAT (Pacific Northwest National Laboratory, Richland, WA 99352) .
CO2 adsorption (a solid sorbent media) and absorption (a liquid sorbent media) are both standard gas purification methods used today in industry. By utilizing microtechnology to improve mass transport and thermal transfer these system have increased efficiency. These systems have potential uses for DOE, DOD, NASA and industry. NASA applications include CO2 collection and compression for fuel processing during a Mars robotic sample return mission. Carbon management of exhaust gases from automobiles, factories, and electrical power plants are all possible applications for microsorption systems. Currently we are designing a one-eighth scale adsorption system for the NASA Micro-ISPP project and testing a microscale absorption apparatus.

Development of an Automated Microfluidic System for DNA Collection, Amplification, and Detection of Pathogens. BETHANY HAGAN (Washington State University, Pullman, WA 99163) CYNTHIA BRUCKNER-LEA (Pacific Northwest National Laboratory, Richland, WA 99352) .
This project was focused on developing and testing automated routines for a microfluidic Pathogen Detection System. The basic pathogen detection routine has three primary components; cell concentration, DNA amplification, and detection. In cell concentration, magnetic beads are held in a flow cell by an electromagnet. Sample liquid is passed through the flow cell and bacterial cells attach to the beads. These beads are then released into a small volume of fluid and delivered to the peltier device for cell lysis and DNA amplification. The cells are lysed during initial heating in the peltier device, and the released DNA is amplified using polymerase chain reaction (PCR) or strand displacement amplification (SDA). Once amplified, the DNA is then delivered to a laser induced fluorescence detection unit in which the sample is detected. These three components create a flexible platform that can be used for pathogen detection in liquid and sediment samples. Future developments of the system will include on-line DNA detection during DNA amplification and improved capture and release methods for the magnetic beads during cell concentration.

Remotely Operated Nondestructive Examination System for Double Shell Tank Inspection. LINDSEY JOHNSON (Stanford University, Palo Alto, CA 94309) TODD SAMUEL (Pacific Northwest National Laboratory, Richland, WA 99352) .
It is required by the WA State Dept. of Ecology that all 28 double shell tanks built at the Hanford Site between 1968 and 1986 be inspected for any pitting or cracking of the walls that would threaten their integrity. To achieve this, a project was begun in FY-1999 whose purpose was to develop and construct a system that will allow detection, localization, and sizing of flaws and cracks in Hanford's Double Shell Waste Tanks (DST's). Prefabricated systems are not available for this type of examination because they cannot reach the highest stress region of the tank, the lower corner, or knuckle region. The system built utilizes a two-step method in which the operator will use Pulse Echo imaging with ultrasonic waves to detect and localize flaws in the knuckle region. The data acquired is sent through the SAFT, or Synthetic Aperture Focusing Technique, which focuses it and enables the operator to find the appropriate area to scan for additional information about the flaw. Next, Tandem scanning, which involves two transducers moving simultaneously, is used to size the flaw. The testing done so far has proven the concept to be a valid one and the project is in the prototype stage but future testing is still necessary to perfect the process and to troubleshoot the system until it is ready for use in the field.

Analysis of Vadose Zone Contaminant Releases at Hanford Site Using VZGRAB Data Extractor. SHARON KARLESKY (Oregon State University, Corvallis, OR 97330) WILLIAM NICHOLS (Pacific Northwest National Laboratory, Richland, WA 99352) .
The Hanford Site was established in 1944 to produce plutonium for use in nuclear weapons. A byproduct of the production process was the release of radioactive and chemically toxic waste to the environment. Since plutonium production ceased in 1988, the Department of Energy (DOE) has pursued a waste management and cleanup mission at the Hanford Site. In 1997, DOE established the Groundwater/Vadose Zone Integration Project, a project that includes development of the System Assessment Capability (SAC) software. This software represents a first-ever attempt to model environmental migration and subsequent impacts for all waste inventories at the Hanford Site. The SAC simulates the transport of contaminants from release at hundreds of locations, through environmental pathways in the vadose zone, the groundwater aquifer, and the Columbia River for the years 1944 to 3050. Moreover, this is done in a stochastic framework, representing uncertainty in results due to uncertainty in input parameters. A data extraction tool, VZGRAB, was developed to efficiently examine the overwhelming quantity of data produced in the vadose zone portion of the SAC. VZGRAB provides the analyst the means to efficiently analyze the vadose zone results with respect to specific site(s), contaminant(s), realization(s), or any combinations thereof. By correlating the results with similar SAC data extractors for other components, the impacts of residual waste can be assessed. This information may be used to guide future waste management and cleanup decisions.

Savannah River Site Mixer Pump Operational Improvement. JAMES KARNESKY (RPI, Troy, NY 12180) FADEL F. ERIAN (Pacific Northwest National Laboratory, Richland, WA 99352) .
Waste mobilization through the use of mixer pumps faces severe challenges to operational efficiency in the storage tanks used on the Savannah River Site. Among these is the possibility that the bottom wall of the tank interferes with the mixing jets, which contributes to the degradation of these jets, and thus the inability of the mixing jets to mobilize waste at outer portions of the tank nearest the floor. This effect, however, is not well understood, and it was the goal of the project enumerated herein to investigate this phenomenon and determine the maximum depths to which the jets are still effective. Both an experimental setup and CFD analysis were applied, and the results obtained were analyzed with the intent of applying them to the mobilization problems of the Savannah River Site.

Memory Device Program Authetication. SAMUEL KORSLUND (Blue Mountain CC, Pendleton, OR 98632) JIM SKORPIK (Pacific Northwest National Laboratory, Richland, WA 99352) .
There are several different types of electronic memory devices, each having their own unique characteristics. Some are one-time-programmable while others can be erased and re-programmed a number of times. Combinations of these different memory devices can be found inside of other electronic components such as microcontrollers, which can also save a program and have that program erased and re-written. These devices are very important in the operation of the circuit in which they are installed, making any error or alteration to the original program greatly effect the resulting operation of the circuit. Therefore, a method of authenticating a microcontroller program is very necessary. One method of performing an authentication is to remove the device from the circuit and place it into a device programmer. The programmer is then interfaced with a computer, and the program is read and displayed on the monitor. From there it can be saved to a file or printed out and compared to an original copy of the program. Any errors or alterations can then be detected and repaired. This method is fairly simple in its procedures, but does require certain pieces of hardware. Most importantly, the programmer and computer, but also equipment is needed to remove the component without doing any damage to it.

Surface Enhanced Raman Scattering of Ag NanoParticles. BRIAN LAMARCHE (Washingtion State University, Pullman, WA 99164) GREG SCHENTER (Pacific Northwest National Laboratory, Richland, WA 99352) .
This research simulates optical scattering observed in the experimental work of Peter Lu and Leyun Zhu. This research is in the initial stages of collaboration between LaMarche, Schenter, Lu, and Zhu. Moreover, this paper describes our simulations of surface enhanced Raman spectroscopy.

Evaluation of Variable Speed Drive Technologies. MICHAEL MULKERIN (American River College, Sacramento, CA 95841) STEVEN A. PARKER (Pacific Northwest National Laboratory, Richland, WA 99352) .
Variable speed drives are more efficient than dampers and bypass loops. Rather than restricting flow or bypassing a heat exchanger, variable speed drives vary the speed of the output fan shaft in order to reach a desired flow. Some of the more popular variable speed drives include, two types of magnetically-coupled variable speed drives and the variable frequency drive. The efficiencies of these drive systems were measured using a dynamometer at the Oregon State University Motor Testing Laboratory. Motors were run according to a theoretical pump and fan curve in order to quantify the efficiency of each drive. The data show that the variable frequency drive is up to eight times more efficient than the magnetically-coupled variable speed drives at the extreme low end of the pump and fan curve and overall more efficient over a wide array of data.

Chemical ionization in ion traps. MATTHEW NEWBURN (WWCC, Walla Walla, WA 99362) ALEXANDER, MICHAEL L (Pacific Northwest National Laboratory, Richland, WA 99352) .
There are inherent amounts of hydrogen peroxide, water vapor, nitrogen, dioxide, and other low mass gases in an ion trap. These chemical species often react with other molecules in ion traps before the mass spectrum can be taken. These reactions can reduce the number of critical ions in the spectrum or they can be used to boost ion concentrations of certain molecules. To be able to optimize the RF voltage in the ring electrode, to allow time for these reactions to occur, one would need to know the reaction constants of these reactions. The production or reduction of three of the most common ambient ions were chosen for this experiment. In particular, O2 + and H3O+ ions will ionize many other neutral molecules. H3O+ was used as a chemical ionization (CI) agent and the reaction constant measured.

The use of Waterjets for Coating Removal. Trent Roth (Bismarck State University, Bismarck, North Dakota 58501) Michael Rinker (Pacific Northwest National Laboratory, Richland, Washington 99352).. TRENT ROTH (Bismarck State College, Bismarck, ND 58501) MICHAEL RINKER (Pacific Northwest National Laboratory, Richland, WA 99352) .
This abstract lacks detail due to business sensitive technologies. High-pressure waterjets are used to clean surfaces in industry. However, surfaces with protective coatings must be cleaned without removing the coatings. High-pressure waterjets were used to find the threshold of steel carbon plates coated with paint. Tests were conducted at various pressures, standoff distances, and traverse rates to determine the proper setting to remove debris while keeping the coatings intact. Results showed that as long as the pressures stayed below 4000 pounds per square inch, the standoff distances and traverse rates did not adversely affect the coatings.

Prototype Performance Evaluation for the Federal Bureau of Investigation Portable Supercritical Fluid Extractor. ANTHONY SCOTT (Eastern Oregon University, La Grande, OR 97850) THOMAS S. ZEMANIAN (Pacific Northwest National Laboratory, Richland, WA 99352) .
The substitution of traditional solvents with supercritical fluids for extraction is an area of many possibilities. While some research has been performed, more is needed to fully investigate the utility of supercritical fluids. The need was expressed for a functional, durable, and smaller portable unit to perform supercritical fluid extraction (SFE) in the field utilizing CO2 as the solvent. Previous generations of portable SFE's have achieved manageable portability, but a smaller unit was requested. The unit was designed and manufactured. The tasks for this project were to run the machine through its paces and test its systems to assure that they operated as designed. From initial testing, it was seen that target pressures were reached in approximately 25-40 minutes, depending on the fill achieved and target pressure. The extractor systems (electronic, Booster/ Generator, and restrictor/recovery) were tested (by stopwatch, thermocouple, observation, and instrument readout) and were functioning as designed. System cool down took between 1½ -2 hrs. Multiple runs through with the extractor showed that it was functioning as designed. The main problem that occurred was electrical and was minor in scope. Improvements such as a Generator dump valve would be useful, in bleeding the gas off for a better liquid fill and for dumping the CO2 after use. This work contributed to the design process of the extractor. Implications of this work include further study of system performances, simple design modifications, and an overall operation view for the end user, The FBI.