The objective of this short-term LDRD project was to acquire the tools needed to use our chemical imaging precision mass analyzer (ChIPMA) instrument to analyze tissue samples. This effort was an outgrowth of discussions with oncologists on the need to find the cellular origin of signals in mass spectra of serum samples, which provide biomarkers for ovarian cancer. The ultimate goal would be to collect chemical images of biopsy samples allowing the chemical images of diseased and nondiseased sections of a sample to be compared. The equipment needed to prepare tissue samples have been acquired and built. This equipment includes an cyro-ultramicrotome for preparing thin sections of samples and a coating unit. The coating unit uses an electrospray system to deposit small droplets of a UV-photo absorbing compound on the surface of the tissue samples. Both units are operational. The tissue sample must be coated with the organic compound to enable matrix assisted laser desorption/ionization (MALDI) and matrix enhanced secondary ion mass spectrometry (ME-SIMS) measurements with the ChIPMA instrument Initial plans to test the sample preparation using human tissue samples required development of administrative procedures beyond the scope of this LDRD. Hence, it was decided to make two types of measurements: (1) Testing the spatial resolution of ME-SIMS by preparing a substrate coated with a mixture of an organic matrix and a bio standard and etching a defined pattern in the coating using a liquid metal ion beam, and (2) preparing and imaging C. elegans worms. Difficulties arose in sectioning the C. elegans for analysis and funds and time to overcome these difficulties were not available in this project. The facilities are now available for preparing biological samples for analysis with the ChIPMA instrument. Some further investment of time and resources in sample preparation should make this a useful tool for chemical imaging applications.
This production process was generated for the satellite system program cables/interconnects group, which in essences had no well defined production process. The driver for the development of a formalized process was based on the set backs, problem areas, challenges, and need improvements faced from within the program at Sandia National Laboratories. In addition, the formal production process was developed from the Master's program of Engineering Management for New Mexico Institute of Mining and Technology in Socorro New Mexico and submitted as a thesis to meet the institute's graduating requirements.
By far the most widely used tool in shock data analysis is the shock response spectrum (SRS). The SRS has gained popularity because of several primary considerations. It has physical significance, it is simple to understand and it is believed to indicate shock severity. Despite its popularity, the SRS has limitations. Foremost among them is the underlying assumption that shock severity is proportional to a time derivative of position, which does not agree with accepted material failure models. Also, the SRS cannot distinguish between naturally occurring, complex shocks and the chirps sometimes used to achieve a desired SRS using electrodynamic shakers with inadequate force capabilities. Thirdly, SODF models used in the computation of the SRS do not accurately predict accelerations in MDOF structures. A relatively new concept has been introduced whereby an analysis is made on the work done on structures by the excitation force. Since work is equal to the change in the energy of a system, this quantity is closely related to failure models based on strain energy such as the Von Mesis criterion. This paper is the first in a series exploring the use of energy-based description of shock motion and structural response. The input energy spectrum has attractive properties which include intuitive physical significance, insensitivity to system parameters such as viscous damping or hysteretic loss, the ability to distinguish between realistic shocks and chirps, and a close relation to accepted material failure models. Input energy spectra can be calculated using SDOF models and, in many cases, accurately predict the energy input to MDOF structures. Finally, this paper gives an introduction to these methods, derives the equations for relevant energy measures and presents relationships to several other shock analysis tools.
Contrary to popular opinion, fully resolved speckles may not be the best option for interferometric applications where it is often advantageous to have unresolved speckles with up to hundreds of speckles in a single camera pixel. This paper seeks to elucidate the effect of unresolved speckles on electronic speckle pattern interferometry (ESPI) and laser Doppler velocimetry (LDV). Related techniques such as temporal speckle pattern interferometry (TSPI) and ultrasonic imaging can also benefit from the ideas presented in this paper. Speckle statistics will be briefly outlined as background to the main topic of optimizing speckle fields for use in interferometry. The complementary speckle-size analysis for LDV is compared to previous published results on ESPI.
As engineering challenges grow in the ever shrinking world of nano-design, methods of making dynamic measurements of these materials and systems will become important. Electron microscopes have imaged these extremely small samples for years, but are incapable of measuring dynamic events. A means of measuring these nano-scale dynamic events is envisioned by converting an electron microscope into a Doppler velocimeter. This idea proceeds from the analogous concept of laser Doppler velocimetry. However, the obvious solution of using a laser to probe at the nano-scale is not feasible because the diffraction limit of light is orders of magnitude larger than the samples of interest. This paper investigates the theoretical underpinnings of using electron beams for Doppler measurements. Potential issues and their solutions, including electron beam coherence and interference will be presented. If answers to these problems can be found, the invention of the Doppler electron velocimeter could yield a completely new measurement concept at atomistic scales.
Proceedings of the SEM Annual Conference and Exposition on Experimental and Applied Mechanics 2007
Raghavendra, Prasad; Paez, Thomas L.
Real mechanical shocks are nonstationary random processes, and it is becoming feasible to model these sources based on practical amounts of measured data. An efficient framework for modeling nonstationary random processes is the Karhunen-Loeve (KL) expansion. It simulates a random source as a mean function plus random deviation from the mean. We have developed an efficient technique for modeling non-Gaussian random processes in the KL framework, and we use it to characterize an electronic component's shock response to the random process. The random process is, in turn, used to create a shock test specification for this electronic component. Numerical results are presented in connection with the random process and test specifications. The electronic component is a speaker and is assembled inside a mobile phone. The test specification will be used in qualifying and selecting a robust component design (or manufacturer) for use inside a mobile phone.
Various techniques and heating methods have been employed to characterize the compressive and tensile behavior of 304L stainless steel over a wide range of test temperatures. Depending on the test temperature, the experimental apparatus required to produce uniform temperatures in the specimens varied significantly. Compression experiments imposed additional difficulty in achieving a uniform temperature throughout the specimen, but were attainable using secondary heating of the test platens. The 304L material was characterized in tension at quasi-static rates and in compression over an extensive range of strain rates to the very high strain rate regime. Strain rate effects were experimentally determined and a reversal in the strain rate effect was discovered at some temperature and strain rate combinations. Dynamic recrystallization was observed at some temperature and strain rate regimes.
Proceedings of the SEM Annual Conference and Exposition on Experimental and Applied Mechanics 2007
Song, Bo; Antoun, Bonnie R.; Chen, Weinong
A split Hopkinson pressure bar (SHPB) was modified to characterize the dynamic compressive behavior of a 304L stainless steel at high temperatures. The shapes of the loading pulses were controlled such that the specimen deformed under dynamic equilibrium at constant strain rates. A heating chamber was used to heat specimen to 815 C and 927 C during dynamic experiments. In order to investigate the recrystallization and other microstructural changes, the SHPB was also modified to load the specimen only once during a test. Moreover, the specimens were quenched 6 and 30 seconds after the dynamic loading was applied to the specimen. Dynamic compressive stress-strain data at high temperatures for the 304L alloy were experimentally obtained.
Proceedings of SPIE - The International Society for Optical Engineering
Koudelka, Melissa L.; Richards, John A.; Koch, Mark W.
Airborne ground moving-target indication (GMTI) radar can track moving vehicles at large standoff distances. Unfortunately, trajectories from multiple vehicles can become kinematically ambiguous, resulting in confusion between a target vehicle of interest and other vehicles. We propose the use of high range resolution (HRR) radar profiles and multinomial pattern matching (MPM) for target fingerprinting and track stitching to overcome kinematic ambiguities. Sandia's MPM algorithm is a robust template-based identification algorithm that has been applied successfully to various target recognition problems. MPM utilizes a quantile transformation to map target intensity samples to a small number of grayscale values, or quantiles. The algorithm relies on a statistical characterization of the multinomial distribution of the sample-by-sample intensity values for target profiles. The quantile transformation and statistical characterization procedures are extremely well suited to a robust representation of targets for HRR profiles: they are invariant to sensor calibration, robust to target signature variations, and lend themselves to efficient matching algorithms. In typical HRR tracking applications, target fingerprints must be initiated on the fly from a limited number of HRR profiles. Data may accumulate indefinitely as vehicles are tracked, and their templates must be continually updated without becoming unbounded in size or complexity. To address this need, an incrementally updated version of MPM has been developed. This implementation of MPM incorporates individual HRR profiles as they become available, and fuses data from multiple aspect angles for a given target to aid in track stitching. This paper provides a description of the incrementally updated version of MPM.
Micro Nano Technology-Based Systems (MNT-Based Systems) are expected to provide unprecedented capabilities for aerospace applications. However we have not sufficiently addressed the reliability of such systems for a number of reasons. For example, our foundational understanding of such systems is incomplete at the basic physics level and our understanding of how individual subsystems interact is much less than we originally assumed. In addition the manner in which we operate during the product realization cycle has large implications for the ultimate reliability we can expect to achieve. Currently it is quite difficult to determine the reliability of MNT-Based Systems and is in fact borne out by a number of estimates we have seen that are unsatisfactory. We shall discuss a number of issues that at present have slowed our progress in developing NMT-Based Systems and have detened us from effectively ascertaining the true "reliability" of such systems.
We present on the first inertial-confinement-fusion ignition facility, the target capsule will be DT filled through a long, narrow tube inserted into the shell. μg-scale shell perturbations Δm' arising from multiple, 10–50 μm-diameter, hollow SiO2 tubes on x-ray-driven, ignition-scale, 1-mg capsules have been measured on a subignition device. Finally, simulations compare well with observation, whence it is corroborated that Δm' arises from early x-ray shadowing by the tube rather than tube mass coupling to the shell, and inferred that 10–20 μm tubes will negligibly affect fusion yield on a full-ignition facility.
In this study, (CFx)n cathode reaction during discharge has been investigated using in situ X-ray diffraction (XRD). Mathematical treatment of the in situ XRD data set was performed using multivariate curve resolution with alternating least squares (MCR–ALS), a technique of multivariate analysis. MCR–ALS analysis successfully separated the relatively weak XRD signal intensity due to the chemical reaction from the other inert cell component signals. The resulting dynamic reaction component revealed the loss of (CFx)n cathode signal together with the simultaneous appearance of LiF by-product intensity. Careful examination of the XRD data set revealed an additional dynamic component which may be associated with the formation of an intermediate compound during the discharge process.
Remote detection of radiation is a difficult problem due to the 1/r 2 fall-off Recent advances in polymer research and nanoscale fabrication methods along with advances in optical Polarimetrie remote sensing systems suggest a solution. The basic device uses a micro-wiregrid infrared polarizer fabricated in conductive polymer. When the polymer is exposed to hard radiation, its conductivity will be affected and the polarization properties of the device will change in a corresponding manner. This change in polarization properties can be determined by optically interrogating the device, possibly from a remote location. We will report on the development of a radiation-sensitive passive dosimeter polymer with very low optical visibility. Progress on material development, lithographic fabrication and optical characterization will be presented.
Niobium doped Lead Zirconate Titanate (PZT) with a Zr/Ti ratio of 95/5 (i.e., PZT 95/5-2Nb) is a ferroelectric with a rhombohedral structure at room temperature. A crystal (or a subdomain within a crystal) exhibits a spontaneous polarization in any one of eight crystallographically equivalent directions. Such a material becomes polarized when subjected to a large electric field. When the electric field is removed, a remanent polarization remains and a bound charge is stored. A displacive phase transition from a rhombohedral ferroelectric phase to an orthorhombic anti-ferroelectric phase can be induced with the application of a mechanical load. When this occurs, the material becomes depoled and the bound charge is released. The polycrystalline character of PZT 95/5-2Nb leads to highly non-uniform fields at the grain scale. These local fields lead to very complex material behavior during mechanical depoling that has important implications to device design and performance. This paper presents a microstructurally based numerical model that describes the 3D non-linear behavior of ferroelectric ceramics. The model resolves the structure of polycrystals directly in the topology of the problem domain and uses the extended finite element method (X-FEM) to solve the governing equations of electromechanics. The material response is computed from anisotropic single crystal constants and the volume fractions of the various polarization variants (i.e., three variants for rhombohedral anti-ferroelectric and eight for rhomobohedral ferroelectric ceramic). Evolution of the variant volume fractions is governed by the minimization of internally stored energy and accounts for ferroelectric and ferroelastic domain switching and phase transitions in response to the applied loads. The developed model is used to examine hydrostatic depoling in PZT 95/5-2Nb.
Making use of polypropylene samples that are selectively labeled with carbon-13 at each of the three unique positions within the repeating unit, we are conducting mass spectral analyses of the volatile organic oxidation products that are produced when the polymer is subjected to elevated temperature in the presence of air. By examination of both the parent and fragmentation ion peaks in the mass spectrum, we are able to identify the positioning of the C-13 labels within the volatile compounds, and thereby map each compound onto its site of origin from within the macromolecular structure of polypropylene. Most of the organic oxidation products are remarkably specific in terms of their genesis from the polymer. The structural results are discussed in terms of the oxidation chemistry of the macromolecule.
This report details the work completed under the TX-100 blade manufacturing portion of the Carbon-Hybrid Blade Developments: Standard and Twist-Coupled Prototype project. The TX-100 blade is a 9 meter prototype blade designed with bend-twist coupling to augment the mitigation of peak loads during normal turbine operation. This structural coupling was achieved by locating off axis carbon fiber in the outboard portion of the blade skins. The report will present the tooling selection, blade production, blade instrumentation, blade shipping and adapter plate design and fabrication. The baseline blade used for this project was the ERS-100 (Revision D) wind turbine blade. The molds used for the production of the TX-100 were originally built for the production of the CX-100 blade. The same high pressure and low pressure skin molds were used to manufacture the TX-100 skins. In order to compensate for the difference in skin thickness between the CX-100 and the TX-100, however, a new TX-100 shear web plug and mold were required. Both the blade assembly fixture and the root stud insertion fixture used for the CX-100 blades could be utilized for the TX-100 blades. A production run of seven TX-100 prototype blades was undertaken at TPI Composites during the month of October, 2004. Of those seven blades, four were instrumented with strain gauges before final assembly. After production at the TPI Composites facility in Rhode Island, the blades were shipped to various test sites: two blades to the National Wind Technology Center at the National Renewable Energy Laboratory in Boulder, Colorado, two blades to Sandia National Laboratory in Albuquerque, New Mexico and three blades to the United States Department of Agriculture turbine field test facility in Bushland, Texas. An adapter plate was designed to allow the TX-100 blades to be installed on existing Micon 65/13M turbines at the USDA site. The conclusion of this program is the kick-off of the TX-100 blade testing at the three testing facilities.
This new program at Sandia is focused on Iodine waste form development for GNEP cycle needs. Our research has a general theme of 'Waste Forms by Design' in which we are focused on silver loaded zeolite waste forms and related metal loaded zeolites that can be validated for chosen GNEP cycle designs. With that theme, we are interested in materials flexibility for iodine feed stream and sequestration material (in a sense, the ability to develop a universal material independent on the waste stream composition). We also are designing the flexibility to work in a variety of repository or storage scenarios. This is possible by studying the structure/property relationship of existing waste forms and optimizing them to our current needs. Furthermore, by understanding the properties of the waste and the storage forms we may be able to predict their long-term behavior and stability. Finally, we are working collaboratively with the Waste Form Development Campaign to ensure materials durability and stability testing.
The vapor-liquid-solid growth process for synthesis of group-IV semiconducting nanowires using silane, germane, disilane and digermane precursor gases has been investigated. The nanowire growth process combines in situ gold seed formation by vapor deposition on atomically clean silicon (111) surfaces, in situ growth from the gaseous precursor(s), and real-time monitoring of nanowire growth as a function of temperature and pressure by a novel optical reflectometry technique. A significant dependence on precursor pressure and growth temperature for the synthesis of silicon and germanium nanowires is observed, depending on the stability of the specific precursor used. Also, the presence of a nucleation time for the onset of nanowire growth has been found using our new in situ optical reflectometry technique.
This report provides strategies for minimizing machining distortion in future designs of aluminum alloy satellite boxes, based in part on key findings from this investigation. The report outlines types of aluminum alloys and how they are heat treated, how residual stresses develop during heat treatment of age hardening alloys, ways residual stresses can be minimized, and the design of machining approaches to minimize distortion in parts that contain residual stresses. Specific recommendations are made regarding alloy selection, heat treatment, stress relieving, and machining procedures for boxes requiring various strength levels with emphasis on 6061 and 7075 aluminum alloys.
Distortion frequently occurs during machining of age hardening aluminum alloys due to residual stresses introduced during the quenching step in the heat treatment process. This report quantifies, compares, and discusses the effectiveness of several methods for minimizing residual stresses and machining distortion in aluminum alloys 7075 and 6061.
This report gives a description of the development of a Stable Local Oscillator (StaLO) multi-chip module (MCM). It is a follow-on report to SAND2006-6414, Stable Local Oscillator Microcircuit. The StaLO accepts a 100MHz input signal and produces output signals at 1.2, 3.3, and 3.6 GHz. The circuit is built as a multi-chip module (MCM), since it makes use of integrated circuit technologies in silicon and lithium niobate as well as discrete passive components. This report describes the development of an MCM-based version of the complete StaLO, fabricated on an alumina thick film hybrid substrate.
The purpose of this LDRD was to study the effect of steady-state neutron and gamma irradiation on the transmission of waveguides designed to operate well in the near- or mid-IR region of the electromagnetic spectrum. In this context, near-IR refers to the region between 1.3 {mu}m and about 2.4 {mu}m, and mid-IR between 3.0 {mu}m and 4.5 {mu}m. Such radiation environments could exist in nuclear power plants or nuclear weapons. Pulsed and steady-state radiation effects had been extensively studied on silica-based optical fibers because they have been the most readily available, most widely used in communications and sensing, and the least expensive. However, silica-based fibers do not transmit well beyond about 1.8 {mu}m and they are virtually opaque in the mid-IR. The mid-IR, as defined above, and beyond, is where vibrational spectroscopy is carried out. This type of sensing is one important application of infrared optical fibers.
Within reactive geochemical transport, several conceptual models exist for simulating sorption processes in the subsurface. Historically, the K{sub D} approach has been the method of choice due to ease of implementation within a reactive transport model and straightforward comparison with experimental data. However, for modeling complex sorption phenomenon (e.g. sorption of radionuclides onto mineral surfaces), this approach does not systematically account for variations in location, time, or chemical conditions, and more sophisticated methods such as a surface complexation model (SCM) must be utilized. It is critical to determine which conceptual model to use; that is, when the material variation becomes important to regulatory decisions. The geochemical transport tool GEOQUIMICO has been developed to assist in this decision-making process. GEOQUIMICO provides a user-friendly framework for comparing the accuracy and performance of sorption conceptual models. The model currently supports the K{sub D} and SCM conceptual models. The code is written in the object-oriented Java programming language to facilitate model development and improve code portability. The basic theory underlying geochemical transport and the sorption conceptual models noted above is presented in this report. Explanations are provided of how these physicochemical processes are instrumented in GEOQUIMICO and a brief verification study comparing GEOQUIMICO results to data found in the literature is given.
Many current and future modeling applications at Sandia including ASC milestones will critically depend on the simultaneous solution of vastly different physical phenomena. Issues due to code coupling are often not addressed, understood, or even recognized. The objectives of the LDRD has been both in theory and in code development. We will show that we have provided a fundamental analysis of coupling, i.e., when strong coupling vs. a successive substitution strategy is needed. We have enabled the implementation of tighter coupling strategies through additions to the NOX and Sierra code suites to make coupling strategies available now. We have leveraged existing functionality to do this. Specifically, we have built into NOX the capability to handle fully coupled simulations from multiple codes, and we have also built into NOX the capability to handle Jacobi Free Newton Krylov simulations that link multiple applications. We show how this capability may be accessed from within the Sierra Framework as well as from outside of Sierra. The critical impact from this LDRD is that we have shown how and have delivered strategies for enabling strong Newton-based coupling while respecting the modularity of existing codes. This will facilitate the use of these codes in a coupled manner to solve multi-physic applications.
This report specifies the way in which Gauss points shall be named and ordered when storing them in an EXODUS II file so that they may be properly interpreted by visualization tools. This naming convention covers hexahedra and tetrahedra. Future revisions of this document will cover quadrilaterals, triangles, and shell elements.
We explored the potential of Quasi-Spherical Direct Drive (QSDD) to reduce the cost and risk of a future fusion driver for Inertial Confinement Fusion (ICF) and to produce megajoule thermonuclear yield on the renovated Z Machine with a pulse shortening Magnetically Insulated Current Amplifier (MICA). Analytic relationships for constant implosion velocity and constant pusher stability have been derived and show that the required current scales as the implosion time. Therefore, a MICA is necessary to drive QSDD capsules with hot-spot ignition on Z. We have optimized the LASNEX parameters for QSDD with realistic walls and mitigated many of the risks. Although the mix-degraded 1D yield is computed to be {approx}30 MJ on Z, unmitigated wall expansion under the > 100 gigabar pressure just before burn prevents ignition in the 2D simulations. A squeezer system of adjacent implosions may mitigate the wall expansion and permit the plasma to burn.
Sandia National Laboratories currently lacks a systematic approach to creating and managing its corporate information; e.g., content management to include metadata standards, taxonomy best practices and style guides. Within this environment, Sandia’s knowledge workers often create and recreate information structures without coordination or collaboration. This document puts forth best practices and standards for taxonomy development at Sandia National Laboratories. It is based on best practices gathered from industry, published industry standards, and the lessons learned from taxonomy projects at Sandia. The document is a direct response to a recommendation made in an FY07 milestone Evaluating the Value of Enterprise Taxonomy at Sandia National Laboratories that “…best practices and standards be developed by the Technical Library staff” (Miller, et. al. 2006).
Acoustic sensing systems are critical elements in detection of sniper events. The microphones developed in this project enable unique sensing systems that benefit significantly from the enhanced sensitivity and extremely compact foot-print. Surface and bulk micromachining technologies developed at Sandia have allowed the design, fabrication and characterization of these unique sensors. We have demonstrated sensitivity that is only available in 1/2 inch to 1 inch studio reference microphones--with our devices that have only 1 to 2mm diameter membranes in a volume less than 1cm{sup 3}.
Emerging BioMicroNanotechnologies have the potential to provide accurate, realtime, high throughput screening of live tumor cells without invasive chemical reagents when coupled with ultrafast laser methods. These optically based methods are critical to advancing early detection, diagnosis, and treatment of disease. The first year goals of this project are to develop a laser-based imaging system integrated with an in- vitro, live-cell, micro-culture to study mammalian cells under controlled conditions. In the second year, the system will be used to elucidate the morphology and distribution of mitochondria in the normal cell respiration state and in the disease state for normal and disease states of the cell. In this work we designed and built an in-vitro, live-cell culture microsystem to study mammalian cells under controlled conditions of pH, temp, CO2, Ox, humidity, on engineered material surfaces. We demonstrated viability of cell culture in the microsystem by showing that cells retain healthy growth rates, exhibit normal morphology, and grow to confluence without blebbing or other adverse influences of the material surfaces. We also demonstrated the feasibility of integrating the culture microsystem with laser-imaging and performed nanolaser flow spectrocytometry to carry out analysis of the cells isolated mitochondria.