18 Matching Results

Search Results

Advanced search parameters have been applied.

Novel Separation of Actinides

Description: The separation of actinides and other elements of interest for nuclear forensics and threat reduction is currently performed using decades-old chemistries and ion-exchange columns. We propose to determine the technical feasibility of a novel method for separating actinide ions in solution. This method is based upon isotachophoresis (ITP), which has been applied in the purification of pharmaceuticals and other biochemical applications. This technique has the potential to separate inorganic ions more effectively than existing methods, which is key to analyzing very small samples. We will perform a quantitative assessment of the effectiveness of specific isotachophoretic approaches including predicting the physical and chemical properties, such as ion mobility, of inorganic ions under specific solvent conditions using a combination of ab initio calculations and semi-empirical methods. We expect to obtain a thorough understanding of the analytical systems parameters under which ITP is most effective for the separation of inorganic samples, including the influence of the double layer surrounding actinide ions, the Debye length for different ions and ion complexes, and Debye-Hueckel limits. Inorganic separations are key to nuclear forensics for countering terrorism and nuclear proliferation. If found to be feasible and potentially superior to currently used separation approaches, ITP could provide the conceptual basis for an improved means to separate samples of nuclear explosion debris for nuclear forensic analysis, in support of the Laboratory's missions in homeland and national security.
Date: February 17, 2011
Creator: Mariella, R
Partner: UNT Libraries Government Documents Department

Sensor systems for the Altair Lunar Lander:

Description: The Altair Lunar Lander will enable astronauts to learn to live and work on the moon for extended periods of time, providing the experience needed to expand human exploration farther into the solar system. My overriding recommendation: Use independent and complementary [sometimes referred to as 'orthogonal'] techniques to disambiguate confounding/interfering signals. E.g.: a mass spectrometer ['MS'], which currently serves as a Majority Constituent Analyzer ['MCA'] can be very valuable in detecting the presence of a gaseous specie, so long as it falls on a mass-to-charge ratio ['m/z'] that is not already occupied by a majority constituent of cabin air. Consider the toxic gas, CO. Both N{sub 2} and CO have parent peaks of m/z = 28, and CO{sub 2} has a fragment peak at m/z = 28 [and at 16 and 12], so the N{sub 2} and CO{sub 2} m/z=28 signals could mask low, but potentially-dangerous levels of CO. However there are numerous surface-sensitive CO detectors, as well as tunable-diode-laser-based CO sensors that could provide independent monitoring of CO. Also, by appending a gas chromatograph ['GC'] as the front-end sample processer, prior to the inlet of the MS, one can rely upon the GC to separate CO from N{sub 2} and CO{sub 2}, providing the crew with another CO monitor. If the Altair Lunar Lander is able to include a Raman-based MCA for N{sub 2}, O{sub 2}, H{sub 2}O, and CO{sub 2}, then each type of MCA would have cross-references, providing more confidence in the ongoing performance of each technique, and decreasing the risk that one instrument might fail to perform properly, without being noticed. See, also Dr. Pete Snyder's work, which states 'An orthogonal technologies sensor system appears to be attractive for a high confidence detection of presence and temporal characterization of bioaerosols.' Another recommendation: Use data fusion for ...
Date: December 22, 2009
Creator: Mariella, R
Partner: UNT Libraries Government Documents Department


Description: Research reported in the thrust area of microtechnology includes: advanced plasma etch processes for high-aspect-ratio, submicron-feature-size applications; integration of PCR amplification and capillary electrophoresis in a DNA analysis device; microactuators for optical interferometry; thin silicon windows; eutectic bonding and fusion bonding; solid-source MBE-grown GaAs/AlGaAs ridge-waveguide semiconductor optical amplifiers; large area lithography; phase-shift lithography; thermally robust optical semiconductor devices using AlGaInAs grown by molecular beam epitaxy; and porous silicon formation and characterization.
Date: February 1, 1997
Creator: Mariella, R.P.
Partner: UNT Libraries Government Documents Department

Microtechnology for instrumentation

Description: For the last two decades, the majority of research and development at LLNL in microtechnology has focused on photonics devices and bulk micromachining, including miccroelectro-mechanical systems and associated areas. For the last ten years, we have used these capabilities to address our analytical instrumentation needs. Just as the miniature photonics have enable the fabrication of analytical instruments that are either higher performance, smaller, more portable, or are combinations of these. Examples of these are our portable thermal cyclers for DNA analysis, our hand-held gas chromatograph, our flow-stream-waveguide-based flow cytometer, and our etched-microchannel electrophoresis systems. This presentation will describe these and related developments.
Date: January 1, 1998
Creator: Mariella, R.
Partner: UNT Libraries Government Documents Department

adendum for )6 report

Description: Prior to using human nasopharyngeal samples, we will use prepared mixtures of viruses with bacteria and eukaryotic cells in our research on microfluidic separation techniques. Some examples of these mixtures are the bacteriophage MS2 with its host bacteria, E. coli, and BSL-1, Risk-Group-1 virus such as fowlpox virus vaccine with its host cell, DF-1, derived from chickens.
Date: February 2, 2007
Creator: Mariella, R; Borucki, M; Miles, R; Claugue, D; Dougherty, G & Fisher, K
Partner: UNT Libraries Government Documents Department

Laser-matter Interaction with Submerged Samples

Description: With the long-term goal in mind of investigating if one could possibly design a 'universal solid-sample comminution technique' for debris and rubble, we have studied pulsed-laser ablation of solid samples that were contained within a surrounding fluid. Using pulses with fluences between 2 J and 0.3 J, wavelengths of 351 and 527 nm, and samples of rock, concrete, and red brick, each submerged in water, we have observed conditions in which {micro}m-scale particles can be preferentially generated in a controlled manner, during the laser ablation process. Others have studied laser peening of metals, where their attention has been to the substrate. Our study uses non-metallic substrates and analyzes the particles that are ablated from the process. The immediate impact of our investigation is that laser-comminution portion of a new systems concept for chemical analysis has been verified as feasible.
Date: March 25, 2010
Creator: Mariella, R; Rubenchik, A; Norton, M; Donohue, G & Roberts, K
Partner: UNT Libraries Government Documents Department

Individualized Medicine

Description: The recent focus of microelectromechanical-systems (MEMS) based instrumentation has largely dealt with increasing the throughput of established processes, including drug screening/drug discovery/combinatorial chemistry, or the miniaturization of accepted bench-top instruments. The miniaturization and automation of procedures that were previously performed manually are included in these activities. We suggest that BioMEMS instrumentation will adopt an additional direction, that of providing information and capabilities to the physician that are not available, today.
Date: August 29, 2000
Creator: Mariella, R.
Partner: UNT Libraries Government Documents Department

Advanced microinstrumentation for rapid DNA sequencing and large DNA fragment separation

Description: Our efforts to develop novel technology for a rapid DNA sequencer and large fragment analysis system based upon gel electrophoresis are described. We are using microfabrication technology to build dense arrays of high speed micro electrophoresis lanes that will ultimately increase the sequencing rate of DNA by at least 100 times the rate of current sequencers. We have demonstrated high resolution DNA fragment separation needed for sequencing in polyacrylamide microgels formed in glass microchannels. We have built prototype arrays of microchannels having up to 48 channels. Significant progress has also been made in developing a sensitive fluorescence detection system based upon a confocal microscope design that will enable the diagnostics and detection of DNA fragments in ultrathin microchannel gels. Development of a rapid DNA sequencer and fragment analysis system will have a major impact on future DNA instrumentation used in clinical, molecular and forensic analysis of DNA fragments.
Date: January 25, 1995
Creator: Balch, J.; Davidson, J.; Brewer, L.; Gingrich, J.; Koo, J.; Mariella, R. et al.
Partner: UNT Libraries Government Documents Department

FY05 LDRD Final Report Molecular Radiation Biodosimetry LDRD Project Tracking Code: 04-ERD-076

Description: In the event of a nuclear or radiological accident or terrorist event, it is important to identify individuals that can benefit from prompt medical care and to reassure those that do not need it. Achieving these goals will maximize the ability to manage the medical consequences of radiation exposure that unfold over a period of hours, days, weeks, years, depending on dose. Medical interventions that reduce near term morbidity and mortality from high but non-lethal exposures require advanced medical support and must be focused on those in need as soon as possible. There are two traditional approaches to radiation dosimetry, physical and biological. Each as currently practiced has strengths and limitations. Physical dosimetry for radiation exposure is routine for selected sites and for individual nuclear workers in certain industries, medical centers and research institutions. No monitoring of individuals in the general population is currently performed. When physical dosimetry is available at the time of an accident/event or soon thereafter, it can provide valuable information in support of accident/event triage. Lack of data for most individuals is a major limitation, as differences in exposure can be significant due to shielding, atmospherics, etc. A smaller issue in terms of number of people affected is that the same dose may have more or less biological effect on subsets of the population. Biological dosimetry is the estimation of exposure based on physiological or cellular alterations induced in an individual by radiation. The best established and precise biodosimetric methods are measurement of the decline of blood cells over time and measurement of the frequency of chromosome aberrations. In accidents or events affecting small numbers of people, it is practical to allocate the resources and time (days of clinical follow-up or specialists laboratory time) to conduct these studies. However, if large numbers of people have been ...
Date: February 3, 2006
Creator: Jones, I M; A.Coleman, M; Lehmann, J; Manohar, C F; Marchetti, F; Mariella, R et al.
Partner: UNT Libraries Government Documents Department

Autonomous system for pathogen detection and identification

Description: This purpose of this project is to build a prototype instrument that will, running unattended, detect, identify, and quantify BW agents. In order to accomplish this, we have chosen to start with the world´┐Ż s leading, proven, assays for pathogens: surface-molecular recognition assays, such as antibody-based assays, implemented on a high-performance, identification (ID)-capable flow cytometer, and the polymerase chain reaction (PCR) for nucleic-acid based assays. With these assays, we must integrate the capability to: l collect samples from aerosols, water, or surfaces; l perform sample preparation prior to the assays; l incubate the prepared samples, if necessary, for a period of time; l transport the prepared, incubated samples to the assays; l perform the assays; l interpret and report the results of the assays. Issues such as reliability, sensitivity and accuracy, quantity of consumables, maintenance schedule, etc. must be addressed satisfactorily to the end user. The highest possible sensitivity and specificity of the assay must be combined with no false alarms. Today, we have assays that can, in under 30 minutes, detect and identify simulants for BW agents at concentrations of a few hundred colony-forming units per ml of solution. If the bio-aerosol sampler of this system collects 1000 Ymin and concentrates the respirable particles into 1 ml of solution with 70% processing efficiency over a period of 5 minutes, then this translates to a detection/ID capability of under 0.1 agent-containing particle/liter of air.
Date: September 24, 1998
Creator: Belgrader, P; Benett, W; Langlois, R; Long, G; Mariella, R; Milanovich, F et al.
Partner: UNT Libraries Government Documents Department

Manipulation of DNA for use in microfluidic devices

Description: MEMS microfluidic systems are becoming increasingly popular as a way to integrate sample preparation and biological assays on a single substrate. The resulting reduction in manual operations and reduced reagent use can lead to significant cost savings in performing biological tests. The authors have explored the use of small scale dielectrophoresis and electrophoresis as a way to manipulate DNA for sample preparation in DNA-based assays. The use of electric fields to manipulate DNA is readily achieved in MEMS devices using standard photolithography techniques to add electrodes to etched flow channels. Dielectrophoresis allows for manipulation of cells and DNA independently of the liquid. This ability is useful in small, valveless fluidic microchips. An advantage of the use of the dielectrophoretic force over an electrophoretic force is that dielectrophoresis works equally well using an AC field, thus reducing trapping of small ions and mitigating electrochemical effects at the electrodes. However, the dielectrophoretic force on the DNA is a function of the volume of the particle; thus, there is a lower practical limit to use of the dielectrophoretic force. Consequently they have also explored methods of manipulating smaller DNA fragments using what they refer to as a stepped electrophoresis method.
Date: November 18, 1998
Creator: Belgrader, P; Bettencourt, K; Davidson, J C; Mariella, R P; Miles, R; Nasarabadi, NS et al.
Partner: UNT Libraries Government Documents Department

Graded Al sub x Ga sub 1-x as photoconductive devices for high efficiency picosecond optoelectronic switching

Description: Picosecond photoconductivity has been achieved for a variety of semiconductor materials by techniques which have now become almost standard. Enhanced scattering by the excessive amount of deep level defects which provide for picosecond recombination lifetimes significantly reduce the mobility, degrading the responsivity of the photoconductor. This paper will present a concept where improved responsivity is achievable by utilizing a graded bandgap Al{sub x}Ga{sub 1-x}As active detecting layer grown on a high defect density GaAs layer by molecular beam epitaxy (MBE). 7 refs., 6 figs.
Date: October 1, 1990
Creator: Morse, J.D.; Mariella, R.P. (Lawrence Livermore National Lab., CA (USA)) & Dutton, R.W. (Stanford Univ., CA (USA). Center for Integrated Systems)
Partner: UNT Libraries Government Documents Department

Femtosecond probe-probe transmission studies of LT-grown GaAs near the band edge

Description: We have studied the near-edge optical response of a LT-grown GaAs sample which was deposited at 300{degrees}C on a Si substrate, and then annealed at 600{degrees}C. The Si was etched away to leave a 1 micron free standing GaAs film. Femtosecond transmission measurements were made using an equal pulse technique at four wavelengths between 825 and 870 nm. For each wavelength we observe both a multipicosecond relaxation time, as well as a shorter relaxation time which is less than 100 femtoseconds.
Date: December 1, 1993
Creator: Radousky, H. B.; Bello, A. F.; Erskine, D. J.; Dinh, L. N.; Bennahmias, M. J.; Perry, M. D. et al.
Partner: UNT Libraries Government Documents Department

FY10 Engineering Innovations, Research and Technology Report

Description: This report summarizes key research, development, and technology advancements in Lawrence Livermore National Laboratory's Engineering Directorate for FY2010. These efforts exemplify Engineering's nearly 60-year history of developing and applying the technology innovations needed for the Laboratory's national security missions, and embody Engineering's mission to ''Enable program success today and ensure the Laboratory's vitality tomorrow.'' Leading off the report is a section featuring compelling engineering innovations. These innovations range from advanced hydrogen storage that enables clean vehicles, to new nuclear material detection technologies, to a landmine detection system using ultra-wideband ground-penetrating radar. Many have been recognized with R&D Magazine's prestigious R&D 100 Award; all are examples of the forward-looking application of innovative engineering to pressing national problems and challenging customer requirements. Engineering's capability development strategy includes both fundamental research and technology development. Engineering research creates the competencies of the future where discovery-class groundwork is required. Our technology development (or reduction to practice) efforts enable many of the research breakthroughs across the Laboratory to translate from the world of basic research to the national security missions of the Laboratory. This portfolio approach produces new and advanced technological capabilities, and is a unique component of the value proposition of the Lawrence Livermore Laboratory. The balance of the report highlights this work in research and technology, organized into thematic technical areas: Computational Engineering; Micro/Nano-Devices and Structures; Measurement Technologies; Engineering Systems for Knowledge Discovery; and Energy Manipulation. Our investments in these areas serve not only known programmatic requirements of today and tomorrow, but also anticipate the breakthrough engineering innovations that will be needed in the future.
Date: January 11, 2011
Creator: Lane, M A; Aceves, S M; Paulson, C N; Candy, J V; Bennett, C V; Carlisle, K et al.
Partner: UNT Libraries Government Documents Department

FY06 Engineering Research and Technology Report

Description: This report summarizes the core research, development, and technology accomplishments in Lawrence Livermore National Laboratory's Engineering Directorate for FY2006. These efforts exemplify Engineering's more than 50-year history of developing and applying the technologies needed to support the Laboratory's national security missions. A partner in every major program and project at the Laboratory throughout its existence, Engineering has prepared for this role with a skilled workforce and technical resources developed through both internal and external venues. These accomplishments embody Engineering's mission: ''Enable program success today and ensure the Laboratory's vitality tomorrow''. Engineering's investment in technologies is carried out primarily through two internal programs: the Laboratory Directed Research and Development (LDRD) program and the technology base, or ''Tech Base'', program. LDRD is the vehicle for creating technologies and competencies that are cutting-edge, or require discovery-class research to be fully understood. Tech Base is used to prepare those technologies to be more broadly applicable to a variety of Laboratory needs. The term commonly used for Tech Base projects is ''reduction to practice''. Thus, LDRD reports have a strong research emphasis, while Tech Base reports document discipline-oriented, core competency activities. This report combines the LDRD and Tech Base summaries into one volume, organized into six thematic technical areas: Engineering Modeling and Simulation; Measurement Technologies; Micro/Nano-Devices and Structures; Precision Engineering; Engineering Systems for Knowledge and Inference; and Energy Manipulation.
Date: January 22, 2007
Creator: Minichino, C; Alves, S W; Anderson, A T; Bennett, C V; Brown, C G; Brown, W D et al.
Partner: UNT Libraries Government Documents Department