This is a collection of papers including abstracts about the celebration of 50 years of excellence in science and engineering at the Savannah River Site. The Symposium Committee invited current and former employees to nominate the innovations to be recognized. Several selection panels of experts in various technical fields reviewed 190 nominations and selected the achievements included in this proceedings. Neither the Symposium Committee nor the selection panels claim that these accomplishments are the best of the best. Instead, they believe that they typify the outstanding quality of science and engineering at the Site during its first half-century.

The National Ignition Facility (NIF) will consist of 192 laser beams that have a total energy of up to 1.8 MJ in the 3rd harmonic ({lambda} = 0.35 {micro}m) with the amount of 2nd harmonic and fundamental light depending on the pulse shape. Material near best focus of the 3rd harmonic light will be vaporized/ablated very rapidly, with a significant fraction of the laser energy converted into plasma x rays. Additional plasma x rays can come from imploding/igniting capsule inside Inertial Confinement Fusion (ICF) hohlraums. Material from outer portions of the target, diagnostic components, first-wall material, and optical components, are ablated by the plasma x rays. Material out to a radius of order 3 cm from target center is also exposed to a significant flux of 2nd harmonic and fundamental laser light. Ablation can accelerate the remaining material to high velocities if it has been fragmented or melted. In addition, the high velocity debris wind of the initially vaporized material pushes on the fragments/droplets and increases their velocity. The high velocity shrapnel fragments/droplets can damage the fused silica shields protecting the final optics in NIF. We discuss modeling efforts to calculate vaporization/ablation, x-ray generation, shrapnel production, and ways to mitigate …

Intelligent, integrated microsystems combine some or all of the functions of sensing, processing information, actuation, and communication within a single integrated package, and preferably upon a single silicon chip. As the elements of these highly integrated solutions interact strongly with each other, the microsystem can be neither designed nor fabricated piecemeal, in contrast to the more familiar assembled products. Driven by technological imperatives, microsystems will best be developed by multi-disciplinary teams, most likely within the flatter, less hierarchical organizations. Standardization of design and process tools around a single, dominant technology will expedite economically viable operation under a common production infrastructure. The production base for intelligent, integrated microsystems has elements in common with the mathematical theory of chaos. Similar to chaos theory, the development of microsystems technology will be strongly dependent on, and optimized to, the initial product requirements that will drive standardization--thereby further rewarding early entrants to integrated microsystem technology.

Concepts developed during research on passive magnetic bearing systems at the Lawrence Livermore National Laboratory gave rise to a new approach to magnetic levitation, the Inductrack. A passive induced-current system employing permanent magnets on the moving vehicle, the Inductrack maximizes levitation forces by a combination of two elements. First, the permanent magnets on the vehicle are arranged in a ''Halbach array,'' a magnet configuration that optimally produces a periodic magnetic field below the array, while canceling the field above the array. Second, the track is made up of close-packed shorted electrical circuits. These circuits couple optimally to the magnetic field of the Halbach array. As a result, levitating forces of order 40 metric tonnes per square meter of Halbach array can be generated, using NdFeB magnets whose weight is a few percent of the levitated weight. Being an induced-current system, the levitation requires motion of the vehicle above a low transition speed. For maglev applications this speed is a few kilometers per hour, walking speed. At rest or in the station auxiliary wheels are needed. The Inductrack is thus fail-safe, that is, drive system failure would only result in the vehicle slowing down and finally settling on its auxiliary wheels. …

Pu300 has particular application in the Arms Control Transparency arena, where very sensitive material is often the subject of tests and measurements. In Arms Control Transparency projects, we attempt to measure attributes of material removed from a nuclear weapon without revealing sensitive information about the material. The measured attribute can either be reported directly or compared against a threshold value. The set of attributes that are measured can be used as a fingerprint for the material. One such attribute for plutonium is material age. Age, in this sense, is defined as the amount of time that has passed since americium separation. The Pu300 system consists of a coaxial HPGe detector and a Canberra Inspector multichannel analyzer. The Inspector allows the high resolution spectral information to be limited by adjusting upper and lower level discriminators so only the information between 330keV and 350keV is collected. The fits of the peaks in the gamma-ray spectrum are fed into a physics code to give an age of the material measured. The physics code is based on the buildup of {sup 241}Am from the decay of {sup 241}Pu.

Measurements have been made to determine safe levels of laser exposure on common metals used in contact with high explosive (HE) samples. Laser light is often used on metals in contact with HE during alignment procedures and experimental data collection. The measurements look at temperature rise of the surface of the metal in contact with HE when laser energy is incident on the opposite side of the metal. The temperature rise was measured as a function of incident laser power, spot size, metal composition and metal thickness. Numerical simulations were also performed to solve the two-dimensional heat flow problem for the experimental geometry. In order to allow a single numerical simulation to represent a large number of physical cases, the equations used in the simulation were expressed in terms of dimensionless variables. The normalized numerical solutions can then be compared with the various experimental configurations used. Calculations and experiment agree well over the range measured.

Sandia National Laboratories has learned through their process of technology transfer that not all high tech transfers are alike. They are not alike by the nature of the customers involved, the process of becoming involved with these customers and finally and most importantly the very nature of the technology itself. Here they focus on technology transfer in the microsystems arena and specifically the sacrificial surface version of microsystems. They have learned and helped others learn that many MEMS applications are best realized through the use of surface micromachining (SMM). This is because SMM builds on the substantial integrated circuit industry. In this paper they review Sandia's process for transferring a disruptive MEMS technology in numerous cases.

This paper will present a survey of the current published work and products available to do off-line data mining for computer network security information. Hundreds of megabytes of data are collected every second that are of interest to computer security professionals. This data can answer questions ranging from the proactive, ''Which machines are the attackers going to try to compromise?'' to the reactive, ''When did the intruder break into my system and how?'' Unfortunately, there's so much data that computer security professionals don't have time to sort through it all. What we need are systems that perform data mining at various levels on this corpus of data in order to ease the burden of the human analyst. Such systems typically operate on log data produced by hosts, firewalls and intrusion detection systems as such data is typically in a standard, machine readable format and usually provides information that is most relevant to the security of the system. Systems that do this type of data mining for security information fall under the classification of intrusion detection systems. It is important to point out that we are not surveying real-time intrusion detection systems. Instead, we examined what is possible when the analysis …

Accelerator mass spectrometry (AMS) measured the relative contribution of ethanol to engine particulate matter (PM) from four ethanol-diesel blended fuels using contemporary grain alcohol as a tracer in low {sup 14}C diesel fuel. An emulsifier (Span 85) or cosolvent (butyl alcohol) facilitated mixing of the 12-25% ethanol blends. We operated the laboratory test engine, a 1993 Cummins B5.9 diesel, at a steady-state medium load and collected PM samples on pre-combusted quartz filters following dilution of engine exhaust in a mini-dilution tunnel. The ethanol blends emitted less PM and NOX than the control. The cosolvent blends reduced PM more effectively than the emulsified blends with similar oxygen content. The distribution of the oxygen, not just the quantity, was an important factor in reducing PM emissions. Any bio-derived fuel component is easily traced on the fossil background. Schemes for measuring volatile fractions of soot and gaseous emissions can be implemented.

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The fundamental atomic-level properties of point and line defects in bcc Ta have been simulated by means of quantum-based multi-ion interatomic potentials derived from the model generalized pseudopotential theory (MGPT). The potentials have been applied to the calculations of point defect formation and migration energies. The results are then compared with the ab-initio electronic-structure results and experimental data, which in turn provide rigorous validation tests of the MGPT potentials. Robust and accurate two- and three-dimensional Green's function (GF) techniques have been developed for static and dynamic simulations of single a/2<111> screw dislocation properties in bcc Ta. The transformation of the dislocation core under the influence of external stress was studied in detail using static GF method. Finite-temperature GF simulation reveals multiple-kink (thermal-kink) formation under an applied stress and the corresponding thermal-kink configuration entropy is estimated to be around 5.23k{sub B}.

We are currently investigating the long term aging of weapon organics in an effort to develop predictive capabilities for functional service life. As part of this effort, we have been studying multimechanism aging of M97 and 53370 stress cushions. Ionizing radiation, thermal degradation, and desiccation all affect the crosslink density and motional dynamics and thus the engineering performance of these materials. Our approach has been to develop molecular level understanding of the effects of such aging mechanisms on polymer properties by a combined approach utilizing solvent swelling, thermal, DMA, molecular modeling, and solid state NMR. This presentation will offer a survey of our current work, concentrating on the application of solid state NMR for correlating structure and polymer dynamics. An overview of the relationships between crosslink density, NMR relaxation times, polymer chain dynamics, and storage modulus measurements will be presented and the advantages of NMR will be discussed. It will be shown that silicone based polymers tend to crosslink upon exposure to {gamma}-radiation, undergo chain scission upon thermal degradation, and stiffen upon desiccation.

Two software packages, VSP 2.1 and FIELDS 3.5, are being used by environmental scientists to plan the number and type of samples required to meet project objectives, display those samples on maps, query a database of past sample results, produce spatial models of the data, and analyze the data in order to arrive at defensible decisions. VSP 2.0 is an interactive tool to calculate optimal sample size and optimal sample location based on user goals, risk tolerance, and variability in the environment and in lab methods. FIELDS 3.0 is a set of tools to explore the sample results in a variety of ways to make defensible decisions with quantified levels of risk and uncertainty. However, FIELDS 3.0 has a small sample design module. VSP 2.0, on the other hand, has over 20 sampling goals, allowing the user to input site-specific assumptions such as non-normality of sample results, separate variability between field and laboratory measurements, make two-sample comparisons, perform confidence interval estimation, use sequential search sampling methods, and much more. Over 1,000 copies of VSP are in use today. FIELDS is used in nine of the ten U.S. EPA regions, by state regulatory agencies, and most recently by several international countries. …

Aircraft crashes are an element of external events required to be analyzed and documented in facility Safety Analysis Reports (SARs) and Nuclear Explosive Safety Studies (NESSs). This paper discusses the localized effects of an aircraft crash impact into the Device Assembly Facility (DAF) located at the Nevada Test Site (NTS), given that the aircraft hits the facility. This was done to gain insight into the robustness of the DAF and to account for the special features of the DAF that enhance its ability to absorb the effects of an aircraft crash. For the purpose of this paper, localized effects are considered to be only perforation or scabbing of the facility. This paper presents an extension to the aircraft crash risk methodology of Department of Energy (DOE) Standard 3014. This extension applies to facilities that may find it necessary or desirable to estimate the localized effects of an aircraft crash hit on a facility of nonuniform construction or one that is shielded in certain directions by surrounding terrain or buildings. This extension is not proposed as a replacement to the aircraft crash risk methodology of DOE Standard 3014 but rather as an alternate method to cover situations that were not considered.

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The Motional Stark Effect (MSE) diagnostic is unique in its ability to measure the current profile and will be essential in ITER for detailed analysis of Advanced Tokamak (AT) and other types of discharges. However, design of a MSE diagnostic for ITER presents many unique challenges. Among these is optical analysis for the convoluted optical path, required for effective neutron shielding, that employs several reflective optics arranged to form a labyrinth. The geometry of the diagnostic has been laid out and the expected Doppler shifts and channel resolution calculated. A model of the optical train has also been developed based on the Mueller matrix formalism. Unfolding the pitch angle for this complicated geometry is not straightforward and possible methods are evaluated. The CORSICA code is used to model a variety of ITER discharges including start-up, Ipramp and reverse shear. The code also incorporates a synthetic MSE diagnostic that can be used to evaluate different viewing locations and optimize channel locations for the above discharges. Simulation of the optical emission spectrum is also underway.

The luminosity in RHIC is limited by vacuum pressure rises, observed with high intensity beams of all species (Au{sup 79+}, d{sup +}, p{sup +}). At injection, the pressure rise could be linked to the existence of electron clouds. In addition, pressure rises in the experimental regions may be caused by electron clouds. They review the existing observations, comparisons with simulations, as well as corrective measures taken and planned.

The Savannah River Technology Center (SRTC) conducted ultrafiltration tests with samples from the Hanford Site's 241-AN-104 tank. The test objectives were to measure filter flux during dewatering and the removal of soluble species during washing. The filtration tests were conducted with the Cells Unit Filter (CUF) currently installed in Cell 16 of the SRTC High Activity Caves. Following filtration, personnel performed inhibited water washing to remove soluble species. Because of the limited volume of concentrated slurry, the washing was performed with a volumetric flask rather than a crossflow filter. Following the washing, personnel chemically cleaned the filter with 1 M nitric acid and periodically measured the clean water flux.

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Detonating solid plastic bonded explosives (PBX) formulated with the insensitive molecule triaminotrinitrobenzene (TATB) exhibit measurable reaction zone lengths, curved shock fronts, and regions of failing chemical reaction at abrupt changes in the charge geometry. A recent set of ''hockey puck'' experiments measured the breakout times of diverging detonation waves in ambient temperature LX-17 (92.5 % TATB plus 7.5% Kel-F binder) and the breakout times at the lower surfaces of 15 mm thick LX-17 discs placed below the detonator-booster plane. The LX-17 detonation waves in these discs grow outward from the initial wave leaving regions of unreacted or partially reacted TATB in the corners of these charges. This new experimental data is accurately simulated for the first time using the Ignition and Growth reactive flow model for LX-17, which is normalized to a great deal of detonation reaction zone, failure diameter and diverging detonation data. A pressure cubed dependence for the main growth of reaction rate yields excellent agreement with experiment, while a pressure squared rate diverges too quickly and a pressure quadrupled rate diverges too slowly in the LX-17 below the booster equatorial plane.

Nickel (Ni) can dissolve a large amount of alloying elements while still maintaining its desirable austenitic microstructure. The resulting alloys are generally divided in families depending on the type of alloying elements they contain. Each one of these families is aimed to specific applications. Corrosive environments in industrial applications are generally divided for example in reducing acids, oxidizing acids, contaminated acids, caustic environments, oxidizing salts, etc. Depending on the application and the environment (electrolyte composition and temperature) several or single alloys may be recommended to fabricate components. The Nichromium-molybdenum (Ni-Cr-Mo) series contains a balanced selection of beneficial alloying elements so it can handle a variety of aggressive environments. By design, Alloy 22 or N06022 is one of the most versatile corrosion resistant nickel alloys since it has an outstanding corrosion resistance both in reducing and oxidizing conditions.

High current discharge channels can neutralize both current and space charge of very intense ion beams. Therefore they are considered as an interesting alternative for the final focus and beam transport in a heavy ion beam fusion reactor. At the GSI accelerator facility, 50 cm long, stable, free-standing discharge channels with currents in excess of 40 kA in 2 to 25 mbar ammonia (NH{sub 3}) gas are investigated for heavy ion beam transport studies. The discharges are initiated by a CO{sub 2} laser pulse along the channel axis before the discharge is triggered. Resonant absorption of the laser, tuned to the {nu}{sub 2} vibration of the ammonia molecule, causes strong gas heating. Subsequent expansion and rarefaction of the gas prepare the conditions for a stable discharge to fulfill the requirements for ion beam transport. This paper describes the laser-gas interaction and the discharge initiation mechanism. We report on the channel stability and evolution, measured by fast shutter and streak imaging techniques. The rarefaction of the laser heated gas is studied by means of a hydrocode simulation.

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The processing rate of high level radioactive waste treatment processes at the Savannah River Site (SRS) is limited by the flow rate of the solid-liquid separation process (crossflow filtration). If SRS could identify and develop a solid-liquid separation technology with a higher processing rate, they could increase the throughput of these processes and complete treating those waste streams in a shorter time, with a significant reduction in life-cycle cost. Savannah River Technology Center (SRTC) personnel identified the rotary microfilter as a technology that could significantly increase filter flux, with improvements of as much as 10X. SRTC is evaluating and developing the rotary microfilter for radioactive service at the SRS. One aspect of this work is evaluating the impact of radiation on the filter unit and filter disks.