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An object-oriented design that provides flexibility in simulation codes is presented. This flexibility allows programmers freedom to easily change solution algorithms and discretization schemes as well as add new solver packages as they become available. Careful attention is paid to separating algorithm, data, and specific problem classes to provide for ease in changing any of these components. Furthermore, data structures are chosen so that each component works with data in a form best suited to its needs. Lastly, we present some experiences and comments on the tradeoffs involved with this design.

The effects of heavy steel confinement on the shock sensitivity of pressed solid high explosives heated to temperatures close to thermal explosion conditions were quantitatively measured. Cylindrical flyer plates accelerated by a 101 mm diameter gas gun impacted preheated explosive charges containing multiple embedded manganin pressure gauges. The high explosive compositions tested were LX-04-01 (85 wt.% HMX and 15 wt.% Viton A) heated to 170 ° C and LX-17 (92.5 wt.% TATB and 7.5 wt.% Kel-F) heated to 250 ° C. Ignition and Growth reactive flow models for heated, heavily confined LX-04-01 and LX-17 were formulated based on the measured pressure histories. LX-17 at 250 ° C is considerably less shock sensitive when confined by steel than when confined by aluminum or unconfined. LX-04-01 at 170 ° C is only slightly less shock sensitive when confined by steel than when it is unconfined. The confinement effect is smaller in LX-04-01, because HMX particle growth i s much less than that of TATB.

It has recently been proposed that certain nonsupersymmetric type II orbifolds have vanishing perturbative contributions to the cosmological constant. We show that techniques of Sen and Vafa allow one to construct dual type II descriptions of these models (some of which have no weakly coupled heterotic dual). The dual type II models are given by the same orbifolds with the string coupling S and a T{sup 2} volume T exchanged. This allows us to argue that in various strongly coupled limits of the original type II models, there are weakly coupled duals which exhibit the same perturbative cancellations as the original models.

The critical impact velocities of 60.1 mm diameter blunt steel projectiles required for ignition of exothermic chemical reaction were determined for heavily confined charges of new and aged (15-30 years) solid HMX-based high explosives. The explosives in order of decreasing impact sensitivity were: PBX 9404; LX-lo; LX-14; PBX 9501; and LX-04. Embedded pressure gauges measured the interior pressure histories. Stockpile aged LX-04 and PBX 9501 from dismantled units were tested and compared to freshly pressed charges. The understanding of explosive aging on impact ignition and other hazards must improve as systems are being deployed longer than their initial estimated lifetimes. The charges that did not react on the first impact were subjected to multiple impacts. While the violence of reaction increased with impact velocity, it remained much lower than that produced by an intentional detonation. Ignition and Growth reactive flow models were developed to predict HMX-based explosive impact sensitivity in other geometries and scenarios.

The technology of room-temperature-setting phosphate ceramics or Ceramicrete{trademark} technology, developed at Argonne National Laboratory (ANL)-East is being used to treat and dispose of low-level mixed wastes through the Department of Energy complex. During the past year, Ceramicrete{trademark} technology was implemented for field application at ANL-West. Debris wastes were treated and stabilized: (a) Hg-contaminated low-level radioactive crushed light bulbs and (b) low-level radioactive Pb-lined gloves (part of the MWIR {number_sign} AW-W002 waste stream). In addition to hazardous metals, these wastes are contaminated with low-level fission products. Initially, bench-scale waste forms with simulated and actual waste streams were fabricated by acid-base reactions between mixtures of magnesium oxide powders and an acid phosphate solution, and the wastes. Size reduction of Pb-lined plastic glove waste was accomplished by cryofractionation. The Ceramicrete{trademark} process produces dense, hard ceramic waste forms. Toxicity Characteristic Leaching Procedure (TCLP) results showed excellent stabilization of both Hg and Pb in the waste forms. The principal advantage of this technology is that immobilization of contaminants is the result of both chemical stabilization and subsequent microencapsulation of the reaction products. Based on bench-scale studies, Ceramicrete{trademark} technology has been implemented in the fabrication of 5-gal waste forms at ANL-West. Approximately 35 kg of real …

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Development of high-temperature superconductor technology will make possible the design and fabrication of smaller, lighter, and more efficient power devices such as motors, generators, transformers, transmission cables, and fault-current limiters. A prototype fault-current limiter, a 200-hp motor, and a 50-m-long transmission cable have already been demonstrated using Ag-clad Bi-2223 superconductor tapes. We have recently enhanced the transport current properties of long lengths of multifilament Ag-clad Bi-2223 tapes through increased packing density of precursor powder, improved mechanical deformation, optimization of conductor design, and adjusted cooling rate. These improved processing parameters had a pronounced effect on the transport critical current of the super-conducting tapes. Our improvements are briefly discussed and their implications are assessed in this paper.

The electronic transference numbers of BCY were relatively low when compared with the protonic numbers. At 800 C, a hydrogen flux of only 0.02 cm{sup 3}/min/cm{sup 2} was obtained in an {approx} 2-rnm-thick BCY sample by short-circuiting the two Pt electrodes. We have developed a novel composite system with improved electronic transport, and preliminary measurements indicate that the new membrane materials can be used in a nongalvanic mode to separate hydrogen from gas mixtures. A maximum flux of 0.12 cm{sup 3}/min/cm{sup 2} has been measured at 800 C in the composite material operated in the nongalvanic mode. Currently, work is underway to further enhance the hydrogen flux in the composite membrane materials.

Vibrational spectra of high-density amorphous ice (hda-ice) for H{sub 2}O and D{sub 2}O samples were measured by inelastic neutron scattering. The measured spectra of hda-ice are closer to those for high-pressure phase ice-VI, but not for low-density ice-Ih. This result suggests that similar to ice-VI the structure of hda-ice should consist of two interpenetrating hydrogen-bonded networks having no hydrogen bonds between themselves.

We have examined the weathered surfaces of 720 year old Hawaiian basalt glasses that were recovered from a subaerial environment with high-resolution transmission electron microscopy (TEM) and energy filtered imaging and electron energy loss spectroscopy (EELS) techniques. Whereas the alteration products (palagonite) were physically detached from the underlying glass in most samples, a gel-like amorphous layer was observed adjacent to the glass in a few samples. To our knowledge, this is the first time a gel layer has been observed on weathered basalt. This is significant because analogous gel layers have been observed on nuclear waste glasses reacted in laboratory tests, and this demonstrates an important similarity in the mechanisms of the weathering of basalt and the corrosion of waste glasses.

The time-of-flight small-angle diffractometer SAND has been serving the scientific user community since 1996. One notable feature of SAND is its capability to measure the scattered intensity in a wide Q (4{pi}sin{theta}/{lambda}, where 2{theta} is the scattering angle and {lambda} is the wavelength of the neutrons) range of 0.0035 to 0.5 {angstrom}{sup {minus}1} in a single measurement. The optical alignment system makes it easy to set up the instrument and the sample. The cryogenically cooled MgO filter reduces the fast neutrons over two orders of magnitude, while still transmitting over 70% of the cold neutrons. A drum chopper running at 15 Hz suppresses the delayed neutron background. SAND has a variety of ancillary equipment to control the sample environment. In this paper we describe the features of the SAND instrument, compare its data on a few standard samples with those measured at well established centers in the world, and display two scientific examples which take advantage of measuring data in a wide Q-range in a single measurement. With a new set of tight collimators the Q{sub min} can be lowered to 0.002 {angstrom}{sup {minus}1} and the presently installed high-angle bank of detectors will extend the Q{sub max} to 2 {angstrom}{sup …

We have investigated the stability and microstructural transformability of the Bi-2223 phase in a silver-sheathed monofilament composite tape fabricated using fine-grained Bi{sub 1.7}Pb{sub 0.3}Sr{sub 1.9}Ca{sub 2.0}-Cu{sub 3.0}O{sub y} (Bi-2223) as the precursor powder. The fully formed Bi-2223 precursor was prepared using established procedures. The purpose of this study was to explore the prospects for growing textured, large-grain-size Bi-2223 from the fine-grained precursor by process parameter perturbations. These perturbations included thermal ramp up variations, programmed heat treatment temperature and oxygen pressure fluctuations, and parameter manipulations during cool-down. Our results show that the types of heat treatments used in conventional oxide-powder-in-tube (OPIT) processing do not facilitate Bi-2223 grain growth when the precursor powder is preconcerted Bi-2223. We also observed that the Bi-2223 partially. decomposed during conventional thermal ramp-up in 0.075 atm O{sub 2}, but that this decomposition can be inhibited by ramping up in a reduced oxygen pressure. A pathway was found for back-reacting the fine-grained Bi-2223 (to Bi-2212, Bi-2201 and nonsuperconducting secondary phases), then reforming large-grained Bi-2223 in a colony microstructure having some distinct differences from that produced during conventional OPIT processing.

Flywheels are being developed for use in an Advanced Locomotive Propulsion System (ALPS) targeted for use in high speed passenger rail service. The ALPS combines high performance, high speed gas turbines, motor/generators and flywheels to provide a light-weight, fuel-efficient power system. Such a system is necessary to avoid the high cost of railway electrification, as is currently done for high speed rail service (>100mph) since diesels are too heavy. The light-weight flywheel rotors are made from multilayered composite materials, and are operated at extremely high energy levels. Metal containment structures have been designed to enclose the rotors and provide encapsulation of the rotor during postulated failure events. One such event is a burst mode failure of the rotor in which the composite rim is assumed to burst into debris that impacts against the containment. This paper presents a finite element simulation of the transient structural response of a subscale metal flywheel containment structure to a rotor burst event.

The ground-state band of the Z=102 isotope {sup 254}No has been identified up to spin 14, indicating that the nucleus is deformed. The deduced quadruple deformation, {beta} = 0.27, is in agreement with theoretical predictions. These observations confirm that the shell-correction energy responsible for the stability of transfermium nuclei is partly derived from deformation. The survival of {sup 254}No up to spin 14 means that its fission barrier persists at least up to that spin.

The use of a digital infrared as a non-destructive evaluation thermography camera (NDE) tool was ex- plored in two separate wind turbine blade fatigue tests. The fwst test was a fatigue test of part of a 13.1 meter wood-epoxy-composite blade. The second test was on a 4.25 meter pultruded fiber glass blade section driven at several mechanical resonant frequencies. The digital infrared camera can produce images of either the static temperature distribution on the surface of the specimen, or the dynamic temperature distribution that is in phase with a specific frequency on a vibrating specimen. The dynamic temperature distribution (due to thermoplastic effects) gives a measure of the sum of the principal stresses at each point on the surface. In the wood- epoxy-composite blade fatigue test, the point of ultimate failure was detected long before failure occurred. The mode shapes obtained with the digital infrared camera, from the resonant blade tests, were in very good agree- ment with the finite-element calculations. In addition, the static temperature images of the resonating blade showed two areas that contained cracks. Close-up dy- namic inf%red images of these areas showed the crack structure that agreed with subsequent dye-penetrant analysis.

In this paper, we characterize surface and sub-surface defects in fused silica and optical coatings using the surface evanescent wave measured by NSOM implemented on a large-stage AFM. A laser irradiates the sample surface in a total internal reflection configuration. The evanescent wave from the surface is collected by an apertured fiber probe of the NSOM. The amplitude of the surface evanescent wave is proportional to the laser intensity at the surface and therefore sensitive to surface as well as sub-surface defects located in the near-field range (~ 100nm). This subsurface region is thought to contain the great majority of polishing-induced defects. The apertured near field fiber probe provides a spatial resolution of ~100nm and the large stage AFM makes it possible to locate defects in samples with diameters up to 6". We are thus able to map out surface- as well as near-surface optical defects in a large optic as a first step in understanding laser damage mechanisms. These observed defects will be exposed in situ to high fluence laser light to correlate with the initiation of laser damage. We have also used NSOM to measure in situ the effect of chemical etching on optical properties of defects. Post-processing …

This talk considers the problem of defining success criteria for petaflop computers. Current expectations for teraflop systems show an alarming acceleration of a trend we have seen for many years in high performance computers. Namely, it is becoming increasingly difficult to effectively use the computational capability of these machines. If this situation is not reversed quickly, the term "petaflop computer" may simply mean the next fastest computer that we cannot use. In many cases, we have some understanding of why we cannot achieve anywhere near the peak performance of these machines on real applications. Effective use of these resources is a highly complex optimization problem that must be solved over all of the different components of each application program. Given this complexity, it is the responsibility of our community to better quantify our progress in developing high perforrnance systems with more meaningful metrics than simply "peak floating point operations per second." We need to develop metrics and tools that help us to enhance the end-to-end performance of solving large scientific applications on these advanced machines.

The research that is described in this paper is part of a program to study strong interaction mechanisms in proton proton collisions. The program consists of two experiments: Brookhaven E766 in which we studied the reactions pp {yields} p+ all charged particles with 27.5 GeV/c incident protons and Fermilab E690 in which we studied the reactions pp {yields} p+ all charged particles with 800 GeV/c incident protons. In these experiments, we employed state-of-the-art data acquisition sys- tems and acquired large samples of data: at Brookhaven we amassed 300 million high multiplicity events and at Fermilab, 5.5 billion events. Our uncertainty in the {Sigma}{sup 0} mass is more than 7 times smaller than the best previous result and was based on 16 times the statistics. Likewise, the {Sigma}{sup 0} - {Lambda}{sup 0} mass difference is more than 14 times more accurate than the previous best result. Finally, we note that this measurement is the first direct measurement of the {Sigma}{sup 0} mass.

We present results of recent kinetic Monte Carlo simulations of the effect of annealing time and ramp rate on boron transient enhanced diffusion (BTED) in low energy ion implanted silicon. The simulations use a database of defect and dopant energetics derived from first principle calculations. We discuss the complete atomistic details of defect and dopant clustering during the anneals, and the dependence of boron TED on ramp rate. The simulations provide a complete time history of the evolution of the active boron fraction during the anneal for a wide variety of conditions. We also studied the lateral spreading of the boron during the annealing for two different conditions, furnace anneal and ramp anneal.

The subject of this paper is the hydrodynamics of pouring molten glass. This involves a class of free surface flows that changes shape from flat film flow on a wall to a round cylindrical jet in the free fall region, which as not previously received much attention.

Localized wave (LW) pulses were produced using a standard Navy array in the anechoic tank at Navy Underwater Weapons Center (NUWC) Keyport. The LW pulses used were the MPS pulse first derived by Ziolkowski, and a new type of pulse based on a superposition of Gaussian beam modes. This new type is motivated by a desire to make a comparison of the MPS pulse with another broad band pulse built from solutions to the wave equation. The superposed Gaussian pulse can be described by parameters which are analogous to those describing the MPS pulse. We compare the directivity patternsand the axial energy decay between the pulses. We find the behavior of the pulses to be similar so that the superposed Gaussian could be another candidate in the class of low diffractive pulses known as localized waves.

We presents results from a predictive atomic level simulation of Boron diffusion in Silicon under a wide variety of implant and annealing conditions. The parameters for this simulation have been extracted from first principle approximation models and molecular dynamics simulations. The results are compared with experiments showing good agreement in all cases. The parameters and reactions used have been implemented into a continuum-level model simulator.

The search for a photonic crystal to confine optical waves in all three dimensions (3D) has proven to be a formidable task. It evolves from an early theoretical suggestion [1,2], a brief skepticism [3-5] and triumph in developing the mm-wave [6-8] and infrared 3D photonic crystals [9]. Yet, the challenge remains, as the ultimate goal for optoelectronic applications is to realize a 3D crystal at X=1.5 pm communication wavelengths. Operating at visible and near infrared wavelengths, X=1-2 pm, a photonic crystal may enhance the spontaneous emission rate [1, 10] and give rise to a semiconductor lasers with a zero lasing threshold[11, 12]. Another important application is optically switching, routing and interconnecting light [13,14] with an ultrafast transmission speed of terabits per second. A photonic crystal may also serve as a platform for integrating an all-optical circuitry with multiple photonic components, such as waveguides and switches, built on one chip [15]. In this Letter, we report on the successful fabrication of a working 3D crystal operating at optical L The minimum feature size of the 3D structure is 180 nanometers. The 3D crystal is free from defects over the entire 6-inch silicon wafer and has an absolute photonic band gap centered …