Currently there are three platforms that offer quasi-isentropic compression or ramp-wave compression (RWC): light-gas gun, magnetic flux (Z-pinch), and laser. We focus here on the light-gas gun technique and on some current theoretical insights from experimental data. A gradient impedance through the length of the impactor provides the pressure pulse upon impactor to the subject material. Applications and results are given concerning high-pressure strength and liquid to solid, phase transition of water plus its associated phase fraction history. We also introduce the Korteweg-deVries-Burgers equation as a means to understand the evolution these RWC waves that propagate through the thickness of the subject material. This equation has the necessary competition between non-linear, dispersion, and dissipation processes, which is shown through observed structures that are manifested in the experimental particle velocity histories. Such methodology points towards a possible quantifiable dissipation, through which RWC experiments may be analyzed.

We used the Near Infrared Camera (NIRC) on Keck I to obtain K{sub s}-band images of four candidate high-redshift radio galaxies selected using optical and radio data in the NOAO Deep Wide-Field Survey in Bootes. Our targets have 1.4 GHz radio flux densities greater than 1 mJy, but are undetected in the optical. Spectral energy distribution fitting suggests that three of these objects are at z > 3, with radio luminosities near the FR-I/FR-II break. The other has photometric redshift z{sub phot} = 1.2, but may in fact be at higher redshift. Two of the four objects exhibit diffuse morphologies in K{sub s}-band, suggesting that they are still in the process of forming.

Transmission Electron Microscopy (TEM) and opticalmeasurements obtained from InN and In1-xGaxNfilms (0<x<0.54)grown by Molecular Beam Epitaxy are presented. Energy gaps measuredbyabsorption, PR, and PL for InN films grown on c-plane Al2O3 were in therange of 0.7 eV. No In or otherinclusions were observed in these films,ruling out the possibility of a strong Mie scattering mechanism. IntheIn1-xGaxN films the relationship between the structural properties andthe optical properties, inparticular the presence or absence of a Stokesshift between absorption and PL, is discussed. TEM studiesshow that highquality layers do not have a Stokes shift. Some films had compositionalordering; thesefilms also showed a shift between absorption edge andluminescence peak.

The proliferation of nuclear, chemical, and biological weapons (collectively known as weapons of mass destruction, or WMD) and the potential acquisition and use of WMD against the world by terrorists are extremely serious threats to international security. These threats are complex and interrelated. There are myriad routes to weapons of mass destruction--many different starting materials, material sources, and production processes. There are many possible proliferators--threshold countries, rogue states, state-sponsored or transnational terrorists groups, domestic terrorists, and even international crime organizations. Motives for acquiring and using WMD are similarly wide ranging--from a desire to change the regional power balance, deny access to a strategic area, or alter international policy to extortion, revenge, or hate. Because of the complexity of this threat landscape, no single program, technology, or capability--no silver bullet--can solve the WMD proliferation and terrorism problem. An integrated program is needed that addresses the WMD proliferation and terrorism problem from end to end, from prevention to detection, reversal, and response, while avoiding surprise at all stages, with different activities directed specifically at different types of WMD and proliferators. Radiation detection technologies are an important tool in the prevention of proliferation. A variety of new developments have enabled enhanced performance in …

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Typical manufacturing methods produce solar cells with an efficiency of 12-15%; and 14% efficiency is the bare minimum for achieving a profit. In work performed at the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley, CA, 5 10-486-577 1)--a US Department of Energy national laboratory that conducts unclassified scientific research and is managed by the University of California--scientist Scott McHugo has obtained keen insights into the impaired performance of solar cells manufactured from polycrystalline silicon. The solar cell market is potentially vast, according to Berkeley Lab. Lightweight solar panels are highly beneficial for providing electrical power to remote locations in developing nations, since there is no need to build transmission lines or truck-in generator fuel. Moreover, industrial nations confronted with diminishing resources have active programs aimed at producing improved, less expensive solar cells. 'In a solar cell, there is a junction between p-type silicon and an n-type layer, such as diffused-in phosphorous', explained McHugo, who is now with Berkeley Lab's Accelerator and Fusion Research Division. 'When sunlight is absorbed, it frees electrons, which start migrating in a random-walk fashion toward that junction. If the electrons make it to the junction; they contribute to the cell's output of electric current. Often, however, …

The use of isoconversional, sometimes called model-free, kinetic analysis methods have recently gained favor in the thermal analysis community. Although these methods are very useful and instructive, the conclusion that model fitting is a poor approach is largely due to improper use of the model fitting approach, such as fitting each heating rate separately. The current paper shows the ability of model fitting to correlate reaction data over very wide time-temperature regimes, including simultaneous fitting of isothermal and constant heating rate data. Recently published data on cellulose pyrolysis by Capart et al. (TCA, 2004) with a combination of an autocatalytic primary reaction and an nth-order char pyrolysis reaction is given as one example. Fits for thermal decomposition of Estane, Viton-A, and Kel-F over very wide ranges of heating rates is also presented. The Kel-F required two parallel reactions--one describing a small, early decomposition process, and a second autocatalytic reaction describing the bulk of pyrolysis. Viton-A and Estane also required two parallel reactions for primary pyrolysis, with the first Viton-A reaction also being a minor, early process. In addition, the yield of residue from these two polymers depends on the heating rate. This is an example of a competitive reaction between …

The large strain deformation response of 6061-T6 and Ti-6Al-4V has been evaluated over a range in strain rates from 10{sup -4} s{sup -1} to over 10{sup 4} s{sup -1}. The results have been used to critically evaluate the strength and damage components of the Johnson-Cook (JC) material model. A new model that addresses the shortcomings of the JC model was then developed and evaluated. The model is derived from the rate equations that represent deformation mechanisms active during moderate and high rate loading. Another model that accounts for the influence of void formation on yield and flow behavior of a ductile metal (the Gurson model) was also evaluated. The characteristics and predictive capabilities of these models are reviewed.

Hydrogen oxidation on platinum is shown to be a surface catalytic chemical reaction that generates a steady state flux of hot (&gt;1 eV) conduction electrons. These hot electrons are detected as a steady-state chemicurrent across Pt/TiO{sub 2} Schottky diodes whose Pt surface is exposed to hydrogen and oxygen. Kinetic studies establish that the chemicurrent is proportional to turnover frequency for temperatures ranging from 298 to 373 K for P{sub H2} between 1 and 8 Torr and P{sub O2} at 760 Torr. Both chemicurrent and turnover frequency exhibit a first order dependence on P{sub H2}.

The free standing nanorodes of aluminum and cobalt oxides were grown on electrode and tested as the anodes directly in the half-cell. The average diameter and length of the nanorods are 80 nm and 200 nm respectively. The aligned nanorods demonstrated high initial capacity from 1200-1400 mAh/g at rate of 0.5C. The gradually decrease of initial capacity was observed. The preliminary characterization shows that the changes of the crystalline structure and morphology during cycling may be responsible for the capacity decay.

Peat cores were collected in 4 remnant marsh islands and 4 drained, farmed islands throughout the Sacramento - San Joaquin Delta of California in order to characterize the peat accretion history of this region. Radiocarbon age determination of marsh macrofossils at both marsh and farmed islands showed that marshes in the central and western Delta started forming between 6030 and 6790 cal yr BP. Age-depth models for three marshes were constructed using cubic smooth spline regression models. The resulting spline fit models were used to estimate peat accretion histories for the marshes. Estimated accretion rates range from 0.03 to 0.49 cm yr{sup -1} for the marsh sites. The highest accretion rates are at Browns Island, a marsh at the confluence of the Sacramento and San Joaquin rivers. Porosity was examined in the peat core from Franks Wetland, one of the remnant marsh sites. Porosity was greater than 90% and changed little with depth indicating that autocompaction was not an important process in the peat column. The mean contribution of organic matter to soil volume at the marsh sites ranges from 6.15 to 9.25% with little variability. In contrast, the mean contribution of inorganic matter to soil volume ranges from 1.40 …

The subject of ''Matter at Extreme Conditions'' encompasses a wide range of phenomena the thrust of which is to address the physical and chemical behaviors of materials exposed to ''abnormal'' conditions of high pressures, temperature extremes, or external fields. Recent advances in theoretical methodologies and first principle computational studies have predicted unusual properties and unraveled a few surprises when matter is subjected to such strains: a reversed and anomalous Doppler effects in shocked periodic media, the possible existence of low temperature liquid metallic state of hydrogen, and a superionic phase of water at high temperature and pressure. A unified approach from quantum mechanical principles allows for exploring such diverse and disparate subjects as ultracold plasmas in a strong magnetic field, and the dynamic aspects of Bose-Einstein condensates. These topics, which are aptly presented in this symposium, are but a few examples of interesting discoveries and methodologies in this active and exciting area of research. The development of reactive force fields from quantum mechanical principles for use in conjunction with molecular dynamics provide us with an invaluable tool for large-scale simulations to study the chemical transformations and decomposition products of complex organic systems at extreme conditions. Simulations implementing classical fields can …

A generalization of Richardson-Gaudin models to the rank-2 SO(5) and SO(3,2) algebras is used to describe systems of two kinds of fermions or bosons interacting through a pairing force. They are applied to the proton-neutron neutron isovector pairing model and to the Interacting Boson Model 2, in the transition from vibration to gamma-soft nuclei, respectively. In both cases, the integrals of motion and their eigenvalues are obtained.

The observed reduction in land surface radiation over the last several decades (1960-1990)---the so-called ''dimming effect''--- and the more recent evidence of a reversal in ''dimming'' over some locations beyond 1990 suggest several consequences on climate, notably on the hydrological cycle. Such a reduction in radiation should imply reduced surface temperature (Ts) and precipitation, which have not occurred. We have investigated the possible causes for the above climate features using a climate model coupled to a dynamic ocean model under natural and anthropogenic conditions. To isolate the aerosol influence on surface radiation trends, we have analyzed transient climate simulations from1960 to 2002 with and without anthropogenic aerosols. Based on a linear trend with aerosol effects included, the global mean change in the surface solar radiation absorbed over land is -0.021+-0.0033 Wm-2yr-1. Although the overall trend is negative, we do note a reversal in dimming after 1990, consistent with observations. Without aerosol effects, the surface solar radiation absorbed over land increases throughout 1960 to 2002, mainly due to the decrease in cloud cover associated with increased greenhouse warming. In spite of a simulated increase in Ts of 0.012 Kyr-1 for 1960 to 2002, the global mean latent heat flux and associated …

The Heavy Ion Fusion Science Virtual National Laboratory(a collaboration of LBNL, LLNL, and PPPL) is using intense ion beams to heat thin foils to the&quot;warm dense matter&quot; regime at&lt;~;; 1 eV, and is developing capabilities for studying target physics relevant to ion-driven inertial fusion energy. The need for rapid target heating led to the development of plasma-neutralized pulse compression, with current amplification factors exceeding 50 now routine on the Neutralized Drift Compression Experiment (NDCX). Construction of an improved platform, NDCX-II, has begun at LBNL with planned completion in 2012. Using refurbished induction cells from the Advanced Test Accelerator at LLNL, NDCX-II will compress a ~;;500 ns pulse of Li+ ions to ~;;1 ns while accelerating it to 3-4 MeV over ~;;15 m. Strong space charge forces are incorporated into the machine design at a fundamental level. We are using analysis, an interactive 1D PIC code (ASP) with optimizing capabilities and centroid tracking, and multi-dimensional Warpcode PIC simulations, to develop the NDCX-II accelerator. This paper describes the computational models employed, and the resulting physics design for the accelerator.

Real prices of major appliances (refrigerators, dishwashers, heating and cooling equipment) have been falling since the late 1970s despite increases in appliance efficiency and other quality variables. This paper demonstrates that historic increases in efficiency over time, including those resulting from minimum efficiency standards, incur smaller price increases than were expected by Department of Energy (DOE) forecasts made in conjunction with standards. This effect can be explained by technological innovation, which lowers the cost of efficiency, and by market changes contributing to lower markups and economies of scale in production of higher efficiency units. We reach four principal conclusions about appliance trends and retail price setting: 1. For the past several decades, the retail price of appliances has been steadily falling while efficiency has been increasing. 2. Past retail price predictions made by DOE analyses of efficiency standards, assuming constant prices over time, have tended to overestimate retail prices. 3. The average incremental price to increase appliance efficiency has declined over time. DOE technical support documents have typically overestimated this incremental price and retail prices. 4. Changes in retail markups and economies of scale in production of more efficient appliances may have contributed to declines in prices of efficient appliances.

We present an efficient pipeline enabling high-throughput analysis of protein structure in solution with small angle X-ray scattering (SAXS). Our SAXS pipeline combines automated sample handling of microliter volumes, temperature and anaerobic control, rapid data collection and data analysis, and couples structural analysis with automated archiving. We subjected 50 representative proteins, mostly from Pyrococcus furiosus, to this pipeline and found that 30 were multimeric structures in solution. SAXS analysis allowed us to distinguish aggregated and unfolded proteins, define global structural parameters and oligomeric states for most samples, identify shapes and similar structures for 25 unknown structures, and determine envelopes for 41 proteins. We believe that high-throughput SAXS is an enabling technology that may change the way that structural genomics research is done.

Over the past 2 years the Tevatron peak luminosity steadily progressed and reached the level of 92e30 cm-2s-1 which exceeds the original Run IIa goal. Over 0.57fb-1 have being delivered to each CDF and D0 experiments since the beginning of the Run II. In parallel to the Collider operation, we have started a project of the luminosity upgrade which should lead to peak luminosities of about 270e30 and total integrated luminosity of 4.4-8.5 fb-1 through FY2009. In this paper we describe the status of the Tevatron Collider complex, essence of the upgrades and novel accelerator technologies to be employed.

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Operation of the Tevatron at lower temperatures, for the purpose of allowing higher energies, has resulted in a renewed interest in thermal modeling of the magnet strings. Static heat load and AC loses in the superconducting coils are initially transported through subcooled liquid helium. Heat exchange between the subcooled liquid and a counter flowing two-phase stream transfers the load to the latent heat. Stratification of the two-phase helium stream has resulted in considerably less heat exchange compared to the original design. Spool pieces have virtually no heat transfer to the two-phase resulting in a ''warm'' dipole just downstream. A model of the magnet string thermal behavior has been developed. The model has been used to identify temperature profiles within magnet strings. The temperature profiles are being used in conjunction with initial magnet quench performance data to predict the location of quench limiting magnets within the Tevatron. During thermal cycles of magnet strings, the model is being used to ''shuffle'' magnets within the magnet string in order to better match the magnets quench performance with its actual predicted temperature. The motivation for this analysis is to raise the operating energy of the Tevatron using a minimal number of magnets from the …

The 4th International Plant Biomechanics Conference facilitated an interdisciplinary exchange between scientists, engineers, and educators addressing the major questions encountered in the field of Plant Biomechanics. Subjects covered by the conference include: Evolution; Ecology; Mechanoreception; Cell Walls; Genetic Modification; Applied Biomechanics of Whole Plants, Plant Products, Fibers & Composites; Fluid Dynamics; Wood & Trees; Fracture Mechanics; Xylem Pressure & Water Transport; Modeling; and Introducing Plant Biomechanics in Secondary School Education.

In this paper they study generalizations of the Diffie-Hellman problems recently used to construct cryptographic schemes for practical purposes. The Group Computational and the Group Decisional Diffie-Hellman assumptions not only enable one to construct efficient pseudo-random functions but also to naturally extend the Diffie-Hellman protocol to allow more than two parties to agree on a secret key. In this paper they provide results that add to their confidence in the GCDH problem. They reach this aim by showing exact relations among the GCDH, GDDH, CDH and DDH problems.

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Recent attention has been given to the proper treatment of the planar traction-free surfaces which typically bound a computational box in three-dimensional dislocation dynamics. This paper presents an alternative to the use of the finite-element method for this purpose. Here, to annul the tractions produced by a sub-surface dislocation segment on a finite-area free surface S, a combination of an image dislocation segment, and a distribution of N prismatic rectangular Volterra dislocation loops meshing S is utilized. The image dislocation segment, with the proper sign selection of the Burgers vector components, annuls the shear stresses, and the normal stress component is annulled discretely at N collocation points representing the centers of the loops. The unknowns in this problem are the magnitudes of the N Burgers vectors for the loops. Once these are determined, one can back calculate the Peach-Koehler force acting on the sub-surface segment and representing the effect of the free surface. As expected, the accuracy of the method improves as the loops continuously decrease in size.