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IBS for RHIC operation below transition energy and various RF systems
N/A
Direct Digital Phase Shift by DDS rf Source
No Description Available.
Numerically Controlled Phase Locked Loop Using Direct Digital Synthesizer
No Description Available.
Impact of the LHC beam abort kicker prefire on high luminosity insertion and CMS detector performance
The effect of possible accidental beam loss in LHC on the IP5 insertion elements and CMS detector is studied via realistic Monte Carlo simulations. Such beam loss could be the consequence of an unsynchronized abort or � in worst case � an accidental prefire of one of the abort kicker modules. Simulations with the STRUCT code show that this beam losses would take place in the IP5 inner and outer triplets. MARS simulations of the hadronic and electro-magnetic cascades induced in such an event indicate severe heating of the inner triplet quadrupoles. In order to protect the IP5 elements, two methods are proposed: a set of shadow collimators in the outer triplet and a prefired module compensation using a special module charged with an opposite voltage (antikicker). The remnants of the accidental beam loss entering the experimental hall have been used as input for FLUKA simulations in the CMS detector. It is shown that it is vital to take measures to reliably protect the expensive CMS tracker components.
Test Plan for New SY Farm Annulus Leak Detectors
This document provides a plan for testing a new annulus leak detection device in the annulus of the waste storage tank 241 SY-102.
Search for neutral Higgs bosons in the multi-b-jet topology in 5.2fb-1 of ppbar collisions at sqrt(s)=1.96 TeV
No Description Available.
Detection of the Energetic Pulsar PSR B1509-58 And Its Pulsar Wind Nebula in MSH 15-52 Using the Fermi-Large Area Telescope
No Description Available.
Fermi Large Area Telescope Observation of a Gamma-Ray Source at the Position of Eta Carinae
No Description Available.
Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni
No Description Available.
FY06 LDRD Final Report Data Intensive Computing
The goal of the data intensive LDRD was to investigate the fundamental research issues underlying the application of High Performance Computing (HPC) resources to the challenges of data intensive computing. We explored these issues through four targeted case studies derived from growing LLNL programs: high speed text processing, massive semantic graph analysis, streaming image feature extraction, and processing of streaming sensor data. The ultimate goal of this analysis was to provide scalable data management algorithms to support the development of a predictive knowledge capability consistent with the direction of Aurora.
Smart Grid Provisions in H.R. 6, 110th Congress
This report provides an overview of Smart Grid, a distribution system that allows for flow of information from a customer's meter in two directions. It discusses both regulatory and technological barriers that have limited the implementation of Smart Grid technology.
Electricity: The Road Toward Restructuring
The Public Utility Holding Company Act of 1935 (PUHCA) and the Federal Power Act (FPA) were enacted to eliminate unfair practices and other abuses by electricity and gas holding companies by requiring federal control and regulation of interstate public utility holding companies. Comprehensive energy legislation has passed the House and Senate. The House passed H.R. 6 on April 11, 2003. On July 31, 2003, the Senate suspended debate on S. 14, inserted the text of H.R. 4 (107th Congress) as a substitute, and passed H.R. 6. A conference agreement was reached November 17, 2003, and passed by the House the next day. H.R. 6 includes an electricity title that would, in part, repeal PUHCA, would prospectively repeal the mandatory purchase requirement under PURPA, and would create an electric reliability organization. On June 15, 2004, H.R. 4503, a comprehensive energy policy bill, passed the House.
State-by-State Comparison of Selected Electricity Restructuring Provisions
Since 1996, twenty-one states have restructured their electricity markets. While the extent of this restructuring varies by state, four issues have generally been considered by all state legislatures: stranded costs, aggregation, universal service, and public benefits. This report compares the treatment of these issues in the restructuring legislation of the twenty-one states. Using information collected directly from the relevant state laws and the rules promulgated by state public utility commissions, this report provides a state-by-state comparison of the restructuring provisions relating to the four issues.
MULTIDENTATE TEREPHTHALAMIDATE AND HYDROXYPYRIDONATE LIGANDS: TOWARDS NEW ORALLY ACTIVE CHELATORS
The limitations of current therapies for the treatment of iron overload or radioisotope contamination have stimulated efforts to develop new orally bioavailable iron and actinide chelators. Siderophore-inspired tetradentate, hexadentate and octadentate terephthalamidate and hydroxypyridonate ligands were evaluated in vivo as selective and efficacious iron or actinide chelating agents, with several metal loading and ligand assessment procedures, using {sup 59}Fe, {sup 238}Pu, and {sup 241}Am as radioactive tracers. The compounds presented in this study were compared to commercially available therapeutic sequestering agents [deferoxamine (DFO) for iron and diethylenetriaminepentaacetic acid (DPTA) for actinides] and are unrivaled in terms of affinity, selectivity and decorporation efficacy, which attests to the fact that high metal affinity may overcome the low bioavailability properties commonly associated to multidenticity.
W and WSi(x) Ohmic Contacts on p- And n-Type GaN
W and WSi ohmic contacts on both p- and n-type GaN have been annealed at temperatures from 300-1000 *C. There is minimal reaction (< 100 ~ broadening of the metal/GaN interface) even at 1000 *C. Specific contact resistances in the 10-5 f2-cm2 range are obtained for WSiX on Si-implanted GaN with a peak doping concentration of- 5 x 1020 cm-3, after annealing at 950 `C. On p-GaN, leaky Schottky diode behavior is observed for W, WSiX and Ni/Au contacts at room temperature, but true ohmic characteristics are obtained at 250 - 300 *C, where the specific contact resistances are typically in the 10-2 K2-cm2 range. The best contacts for W and WSiX are obtained after 700 *C annealing for periods of 30- 120 sees. The formation of &WzN interracial phases appear to be important in determining the contact quality.
Facet Model and Mathematical Morphology for Surface Characterization
This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be successful in detecting the various topographic characteristics of the surface of the slurry. Pertinent topographic elements are retained and a filtered image computed. Carefully tailored morphological operators are then applied to detect and segment regions of interest. Those regions are then selected according to their size, elongation, and orientation. Their bounding rectangles are computed and represented. Also addressed in this paper are aspects of the real time implementation of this algorithm for on-line use. The algorithm is tested on over 500 images of slurry and is found to segment and characterize nonuniformities on all 500 images.
Corrosion behavior of stainless steel-zirconium alloy waste forms.
Stainless steel-zirconium (SS-Zr) alloys are being considered as waste forms for the disposal of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The baseline waste form for spent fuels from the EBR-II reactor is a stainless steel-15 wt.% zirconium (SS-15Zr) alloy. This article briefly reviews the microstructure of various SS-Zr waste form alloys and presents results of immersion corrosion and electrochemical corrosion tests performed on these alloys. The electrochemical tests show that the corrosion behavior of SS-Zr alloys is comparable to those of other alloys being considered for the Yucca Mountain geologic repository. The immersion tests demonstrate that the SS-Zr alloys are resistant to selective leaching of fission product elements and, hence, suitable as candidates for high-level nuclear waste forms.
Theoretical Investigation of the Performance of Proportional Navigation Guidance Systems-Effect of Method of Positioning the Radar Antenna on the Speed of Response
Memorandum presenting a linear theoretical analysis of the performance of three proportional navigation guidance systems installed in a given supersonic, variable-incidence, boost-glide, antiaircraft missile at Mach numbers of 2.7 and 1.3. It is shown that, with the antenna stabilized in space, the effect of component lags on the response is small, so that the speed of response is small, so that the speed of response can be made to approach closely that of the airframe alone.
Theoretical Investigation of the Performance of Proportional Navigation Guidance Systems: Effect of Method of Positioning the Radar Antenna on the Speed of Response
Memorandum presenting a linear theoretical analysis made of the performance of three proportional navigation guidance systems installed in a given supersonic, variable-incidence, boost-glide, antiaircraft missile at Mach numbers of 2.7 and 1.3. Three guidance systems are compared on the basis of the maximum obtainable speed of response of the missile and guidance-system combination consistent with adequate stability. Results regarding the effect of method of positioning the radar antenna on the speed of response, effect of Mach number on response, and effect of networks are provided.
Development of residential-conservation-survey methodology for the US Air Force. Interim report. Task two
A US Air Force (USAF) Residential Energy Conservation Methodology was developed to compare USAF needs and available data to the procedures of the Residential Conservation Service (RCS) program as developed for general use by utility companies serving civilian customers. Attention was given to the data implications related to group housing, climatic data requirements, life-cycle cost analysis, energy saving modifications beyond those covered by RCS, and methods for utilizing existing energy consumption data in approaching the USAF survey program. Detailed information and summaries are given on the five subtasks of the program. Energy conservation alternatives are listed and the basic analysis techniques to be used in evaluating their thermal performane are described. (MCW)
A hybrid vehicle evaluation code and its application to vehicle design. Revision 2
This paper describes a hybrid vehicle simulation model which can be applied to many of the vehicles currently being considered for low pollution and high fuel economy. The code operates in batch mode with all the vehicle information stored in data files. The code calculates power train dimensions, fuel economy for three driving schedules, time for 0-96 km/h at maximum acceleration, hill climbing performance, and pollution generation rates. This paper also documents the application of the code to a hybrid vehicle that utilizes a hydrogen internal combustion engine. The simulation model is used for parametric studies of the vehicle. The results show the fuel economy of the vehicle as a function of vehicle mass, aerodynamic drag, engine efficiency, accessory load, and flywheel efficiency. The code also calculates the minimum flywheel energy and power to obtain a desired performance. The hydrogen hybrid vehicle analyzed in the paper has a range of 480 km (300 miles), with a predicted gasoline equivalent fuel efficiency of 33.7 km/liter (79.3 mpg).
Analysis of the Effect of Geometry Generated Turbulence on HCCI Combustion by Multi-Zone Modeling
This paper illustrates the applicability of a sequential fluid mechanics, multi-zone chemical kinetics model to analyze HCCI experimental data for two combustion chamber geometries with different levels of turbulence: a low turbulence disc geometry (flat top piston), and a high turbulence square geometry (piston with a square bowl). The model uses a fluid mechanics code to determine temperature histories in the engine as a function of crank angle. These temperature histories are then fed into a chemical kinetic solver, which determines combustion characteristics for a relatively small number of zones (40). The model makes the assumption that there is no direct linking between turbulence and combustion. The results show that the multi-zone model yields good results for both the disc and the square geometries. The model makes good predictions of pressure traces and heat release rates. The experimental results indicate that the high turbulence square geometry has longer burn duration than the low turbulence disc geometry. This difference can be explained by the sequential multi-zone model, which indicates that the cylinder with the square bowl has a thicker boundary layer that results in a broader temperature distribution. This broader temperature distribution tends to lengthen the combustion, as cold mass within the cylinder takes longer to reach ignition temperature when compressed by the expansion of the first burned gases. The multi-zone model, which makes the basic assumption that HCCI combustion is controlled by chemical kinetics, is therefore capable of explaining the experimental results obtained for different levels of turbulence, without considering a direct interaction between turbulence and combustion. A direct connection between turbulence and HCCI combustion may still exists, but it seems to play a relatively minor role in determining burn duration at the conditions analyzed in this paper.
Analysis of Electric Energy Usage in Air Force Houses Equipped with Air-to-Air Heat Pumps
From Introduction: "One part of this study, which is presented in this Monograph, consists of an analysis of electric energy usage and electric power demand data obtained from a sample group of occupied houses at Little Rock Air Force Base in Arkansas, equipped with heat pumps, water heaters, cooking ranges, clothes dryers, and miscellaneous appliances all operated by electricity."
Spectroscopic Analyses of the Biofuels-Critical Phytochemical Coniferyl Alcohol and Its Enzyme-Catalyzed Oxidation Products
Lignin composition (monolignol types of coniferyl, sinapyl or p-coumaryl alcohol) is causally related to biomass recalcitrance. We describe multiwavelength (220, 228, 240, 250, 260, 290, 295, 300, 310 or 320 nm) absorption spectroscopy of coniferyl alcohol and its laccase- or peroxidase-catalyzed products during real time kinetic, pseudo-kinetic and endpoint analyses, in optical turn on or turn off modes, under acidic or basic conditions. Reactions in microwell plates and 100 mu L volumes demonstrated assay miniaturization and high throughput screening capabilities. Bathochromic and hypsochromic shifts along with hyperchromicity or hypochromicity accompanied enzymatic oxidations by laccase or peroxidase. The limits of detection and quantitation of coniferyl alcohol averaged 2.4 and 7.1 mu M respectively, with linear trend lines over 3 to 4 orders of magnitude. Coniferyl alcohol oxidation was evident within 10 minutes or with 0.01 mu g/mL laccase and 2 minutes or 0.001 mu g/mL peroxidase. Detection limit improved to 1.0 mu M coniferyl alcohol with Km of 978.7 +/- 150.7 mu M when examined at 260 nm following 30 minutes oxidation with 1.0 mu g/mL laccase. Our assays utilized the intrinsic spectroscopic properties of coniferyl alcohol or its oxidation products for enabling detection, without requiring chemical synthesis or modification of the substrate or product(s). These studies facilitate lignin compositional analyses and augment pretreatment strategies for reducing biomass recalcitrance.
Response to Terrorism: Legal Aspects of the Use of Military Force
No Description Available.
Measurement of Separate Cosmic-Ray Electron And Positron Spectra with the Fermi Large Area Telescope
No Description Available.
Constraints on the Cosmic-Ray Density Gradient Beyond the Solar Circle From Fermi Gamma-Ray Observations of the Third Galactic Quadrant
We repot an analysis of the interstellar ϒ-ray emission in the third Galactic quadrant measured by he Fermi Large Area Telescope. The window encompassing the Galactic plane from longitude 210° to 250° has kinematically well-defined segments of the Local and the Perseus arms, suitable to study the cosmic-ray densities across the outer Galaxy. We measure no large gradient with Galactocentric distance of the ϒ-ray eissivitties per interstellar H atom over the regions sampled in this study. The gradient depends, however, on the optical depth correction applied to derive the H1 column densities. No significant variations are found in the interstellar spectra in the outer Galaxy, indicating similar shapes of the cosmic-ray spectrum up to the Perseus arm for particles with GeV to tens of GeV energies. The emissivity as a function of Galactocentric radius does not show a large enhancement in the spiral arms with respect to the interarm region. The measured emissivity gradient is flatter that expectations based on a cosmic-ray propagation model using the radial distribution of supernova remnants and uniform diffusion properties. In this context, observations require a larger halo size and/or a flatter CR source distribution than usually assumed. The molecular mass calibrating ratio, X$sub CO$ = N(H$sub 2$)/W$sub CO$, is found to be (2.08±0.11) x 10$sup 20$ cm$sup -2$ (K km s$sup -1$)$sup -1$ in the Local-arm clouds and is not significantly sensitive to the choice of H1 spin temperature. No significant variations are found for clouds in the interarm region.
Qcd physics: measurement of the cross section for prompt diphoton production in p anti-p collisions at s**(1/2) = 1.96 tev
We report a measurement of the rate of prompt diphoton production in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample of 207 pb{sup -1} collected with the upgraded Collider Detector at Fermilab (CDF II). The background from non-prompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.
Measurement of the Moments of the Hadronic Invariant Mass Distribution in Semileptonic Beta Decays
Using 180 pb{sup -1} of data collected with the CDF II detector at the Tevatron, we measure the first two moments of the hadronic invariant mass-squared distribution in charmed semileptonic B decays. From these we determine the non-perturbative Heavy Quark Effective Theory parameters {Lambda} and {lambda}{sub 1} used to relate the B meson semileptonic branching ratio to the CKM matrix element |V{sub cb}|.
TWRS technical baseline database manager definition document
This document serves as a guide for using the TWRS Technical Baseline Database Management Systems Engineering (SE) support tool in performing SE activities for the Tank Waste Remediation System (TWRS). This document will provide a consistent interpretation of the relationships between the TWRS Technical Baseline Database Management software and the present TWRS SE practices. The Database Manager currently utilized is the RDD-1000 System manufactured by the Ascent Logic Corporation. In other documents, the term RDD-1000 may be used interchangeably with TWRS Technical Baseline Database Manager.
Design Concepts for the Cherenkov Telescope Array
No Description Available.
Industrial alliances
The United States is emerging from the Cold War era into an exciting, but challenging future. Improving the economic competitiveness of our Nation is essential both for improving the quality of life in the United States and maintaining a strong national security. The research and technical skills used to maintain a leading edge in defense and energy now should be used to help meet the challenge of maintaining, regaining, and establishing US leadership in industrial technologies. Companies recognize that success in the world marketplace depends on products that are at the leading edge of technology, with competitive cost, quality, and performance. Los Alamos National Laboratory and its Industrial Partnership Center (IPC) has the strategic goal to make a strong contribution to the nation`s economic competitiveness by leveraging the government`s investment at the Laboratory: personnel, infrastructure, and technological expertise.
Energy calibration scheme for acoustic emission
The calibration technique described is an attempt to determine the actual energy release from the events causing emission bursts in beryllium and to quantitatively evaluate the effects of specimen geometry on the apparent energy per burst. (GHT)
ALTERNATIVE MATERIALS TO PD MEMBRANES FOR HYDROGEN PURIFICATION
Development of advanced hydrogen separation membranes in support of hydrogen production processes such as coal gasification and as front end gas purifiers for fuel cell based system is paramount to the successful implementation of a national hydrogen economy. Current generation metallic hydrogen separation membranes are based on Pd-alloys. Although the technology has proven successful, at issue is the high cost of palladium. Evaluation of non-noble metal based dense metallic separation membranes is currently receiving national and international attention. The focal point of the reported work was to evaluate two different classes of materials for potential replacement of conventional Pd-alloy purification/diffuser membranes. Crystalline V-Ni-Ti and Amorphous Fe- and Co-based metallic glass alloys have been evaluated using both electrochemical and gaseous hydrogen permeation testing techniques..
Radiological Survey Results for Areas A1 North, A5A, A6, and B2 at the Molycorp Washington Remediation Project, Washington, Pennsylvania
Perform radiological surveys of the Molycorp Washington Remediation Project (MWRP) facility in Washington, Pennsylvania
EXAMINATION OF SODIUM, BERYLLIUM, INCONEL PUMP LOOPS, NUMBERS 1 AND 2
From data obtained from two loops, the use of beryllium in Inconel systems containing molten sodium appears feasible if the temperature is held below 1200 deg F. (J.E.D.)
Iran: Regional Perspectives and U.S. Policy
This report provides a description of Iran's neighbors' policies and interests, options for Congressional consideration, and an analysis of potential regional implications.
Nucleation of GaN/AlN quantum dots
We study the nucleation of GaN islands grown by plasma-assisted molecular-beam epitaxy on AlN in a Stranski-Krastanov mode. In particular, we assess the variation of their height and density as a function of GaN coverage. We show that the GaN growth passes four stages: initially, the growth is layer-by-layer; subsequently, bidimensional precursor islands form, which transform into genuine three-dimensional islands. During the latter stage, the height and the density of the islands increase with GaN coverage until the density saturates. During further GaN growth, the density remains constant and a bimodal height distribution appears. The variation of island height and density as a function of substrate temperature is discussed in the framework of an equilibrium model for Stranski-Krastanov growth [R. E. Rudd et al., Phys. Rev. Lett. 90, 146101 (2003)].
Surface Passivation of Germanium Nanowires
The surface of single crystal, cold-wall CVD-grown germanium nanowires was studied by synchrotron radiation photoemission spectroscopy (SR-PES) and also by conventional XPS. The as-grown germanium nanowires seem to be hydrogen terminated. Exposure to laboratory atmosphere leads to germanium oxide growth with oxidation states of Ge{sup 1+}, Ge{sup 2+}, Ge{sup 3+}, while exposure to UV light leads to a predominance of the Ge{sup 4+} oxidation state. Most of the surface oxide could be removed readily by aqueous HF treatment which putatively leaves the nanowire surface hydrogen terminated with limited stability in air. Alternatively, chlorine termination could be achieved by aq. HCl treatment of the native oxide-coated nanowires. Chlorine termination was found to be relatively more stable than the HF-last hydrogen termination.
Pig shipping container test sequence
This test plan outlines testing of the integrity of the pig shipping container. It is divided into four sections: (1) drop test requirements; (2) test preparations; (3) perform drop test; and (4) post-test examination.
Kaon Production and Kaon to Pion Ratio in Au+Au Collisions at {radical}(s{sub NN})=130 GeV
Mid-rapidity transverse mass spectra and multiplicity densities of charged and neutral kaons are reported for Au+Au collisions at {radical}s{sub NN}=130 GeV at RHIC. The spectra are exponential in transverse mass, with an inverse slope of about 280 MeV in central collisions. The multiplicity densities for these particles scale with the negative hadron pseudo-rapidity density. The charged kaon to pion ratios are K{sup +}/{pi}{sup -} = 0.161 {+-} 0.002(stat) {+-} 0.024(syst) and K{sup -}/{pi}{sup -} = 0.146 {+-} 0.002(stat) {+-} 0.022(syst) for the most central collisions. The K{sup +}/{pi}{sup -} ratio is lower than the same ratio observed at the SPS while the K{sup -}/{pi}{sup -} is higher than the SPS result. Both ratios are enhanced by about 50% relative to p+p and {bar p}+p collision data at similar energies.
Health problems associated with investigation of off-plant uranium rolling. Rough draft
The following is a report of a trip to the Simonds Saw & Steel Company, Lockport, New York, on May 3, 1949. The purpose of the visit was to observe the various operations involved in the rolling of uranium rods at this plant and health problems associated with the rolling operations.
Status of Plasma Electron Hose Instability Studies in FACET
In the FACET plasma-wakefield acceleration experiment a dense 23 GeV electron beam will interact with lithium and cesium plasmas, leading to plasma ion-channel formation. The interaction between the electron beam and the plasma sheath-electrons may lead to a fast growing electron hose instability. By using optics dispersion knobs to induce a controlled z-x tilt along the beam entering the plasma, we investigate the transverse behavior of the beam in the plasma as function of the tilt. We seek to quantify limits on the instability in order to further explore potential limitations on future plasma wakefield accelerators due to the electron hose instability. The FACET plasma-wakefield experiment at SLAC will study beam driven plasma wakefield acceleration. A dense 23 GeV electron beam will interact with lithium or cesium plasma, leading to plasma ion-channel formation. The interaction between the electron beam and the plasma sheath-electrons drives the electron hose instability, as first studied by Whittum. While Ref. [2] indicates the possibility of a large instability growth rate for typical beam and plasma parameters, other studies including have shown that several physical effects may mitigate the hosing growth rate substantially. So far there has been no quantitative benchmarking of experimentally observed hosing in previous experiments. At FACET we aim to perform such benchmarking by for example inducing a controlled z-x tilt along the beamentering the plasma, and observing the transverse behavior of the beam in the plasma as function. The long-term objective of these studies is to quantify potential limitations on future plasma wakefield accelerators due to the electron hose instability.
Beam Dynamics Study of X-Band Linac Driven X-Ray FELS
Several linac driven X-ray Free Electron Lasers (XFELs) are being developed to provide high brightness photon beams with very short, tunable wavelengths. In this paper, three XFEL configurations are proposed that achieve LCLS-like performance using X-band linac drivers. These linacs are more versatile, efficient and compact than ones using S-band or C-band rf technology. For each of the designs, the overall accelerator layout and the shaping of the bunch longitudinal phase space are described briefly. During the last 40 years, the photon wavelengths from linac driven FELs have been pushed shorter by increasing the electron beam energy and adopting shorter period undulators. Recently, the wavelengths have reached the X-ray range, with FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source) successfully providing users with soft and hard X-rays, respectively. FLASH uses a 1.2 GeV L-band (1.3 GHz) superconducting linac driver and can deliver 10-70 fs FWHM long photon pulses in a wavelength range of 44 nm to 4.1 nm. LCLS uses the last third of the SLAC 3 km S-band (2.856 GHz) normal-conducting linac to produce 3.5 GeV to 15 GeV bunches to generate soft and hard X-rays with good spatial coherence at wavelengths from 2.2 nm to 0.12 nm. Newer XFELs (at Spring8 and PSI) use C-band (5.7 GHz) normal-conducting linac drivers, which can sustain higher acceleration gradients, and hence shorten the linac length, and are more efficient at converting rf energy to bunch energy. The X-band (11.4 GHz) rf technology developed for NLC/GLC offers even higher gradients and efficiencies, and the shorter rf wavelength allows more versatility in longitudinal bunch phase space compression and manipulation. In the following sections, three different configurations of X-band linac driven XFELs are described that operate from 6 to 14 GeV. The first (LOW CHARGE DESIGN) has an electron bunch charge …
Evaluating the Effects of Tri-Butyl Phosphate and Normal Paraffin Hydrocarbon in Simulated Low-Activity Waste Solution on Ion Exchange
Ultrafiltration and ion exchange are among the pretreatment processes selected for the WTP at the Hanford Site. This study is the second part of a two-part study on Evaluating the Effects of Tri-Butyl Phosphate and Normal Paraffin Hydrocarbon in Simulated Low-Activity Waste Solution on Ultrafiltration and Ion Exchange.
LITERATURE REVIEW ON MAXIMUM LOADING OF RADIONUCLIDES ON CRYSTALLINE SILICOTITANATE
Plans are underway to use small column ion exchange (SCIX) units installed in high-level waste tanks to remove Cs-137 from highly alkaline salt solutions at Savannah River Site. The ion exchange material slated for the SCIX project is engineered or granular crystalline silicotitanate (CST). Information on the maximum loading of radionuclides on CST is needed by Savannah River Remediation for safety evaluations. A literature review has been conducted that culminated in the estimation of the maximum loading of all but one of the radionuclides of interest (Cs-137, Sr-90, Ba-137m, Pu-238, Pu-239, Pu-240, Pu-241, Am-241, and Cm-244). No data was found for Cm-244.
An Evaluation of Mercury Cooled Breeder Reactors
Abstract: The technical feasibility and economic potential of fast breeder power reactor systems cooled with boiling mercury have been investigated by American-Standard under the United States Atomic Energy Commission's New Reactor Concepts Evaluation Program.
Army Gas-Cooled Reactor Systems Program Quarterly Progress Report: July 1 - September 30, 1964
Report documenting the progress of the Army Gas-Cooled Reactor Systems Program to develop a mobile nuclear power plant for military field operation.
New Neutron Rich Nuclei Near {sup 208}Pb
The level properties near the stable doubly-magic nuclei formed the experimental grounds for the theoretical description of nuclear structure. However with a departure from the beta-stability line, the classical well-established shell structure might be modified. In particular, it may even vanish for extremely exotic neutron-rich nuclei near the neutron-drip line. Presently, it is impossible to verify such predictions by a direct experimental studies of these exotic objects. However, one may try to observe and understand the evolution of the nuclear structure while departing in the experiment as far as possible from the stable nuclei. An extension of experimental nuclear structure studies towards the nuclei characterized by high neutron excess is crucial for such verifications as well as for the {tau}-process nucleosynthesis scenario. Heavy neutron-rich nuclei, south-east of doubly-magic {sup 208}Pb, were always very difficult to produce and investigate. The nuclei like {sup 218}Po and {sup 214}Pb or {sup 210}Tl marked the border line of known nuclei from the beginning of the radioactivity era for over ninety years. To illustrate the difficulties, one can refer to the experiments employing the on-line mass separator technique. A spallation of heavy targets like {sup 232}Th and {sup 238}U by high-energy protons was proven as a source of heavy neutron-rich nuclei. The isotopes near and beyond doubly-magic {sup 208}Pb were produced too. However, such studies often suffered from an isobaric contamination of much more strongly produced and efficiently released elements like francium or radon and their decay products. A new experimental technique, based on the pulsed release element selective method recently developed at the PS Booster-ISOLDE at CERN [7,8,9] greatly reduces the contamination of these very short-lived {alpha}-emitters (Z {ge} 84) for the isobaric mass chains A=215 to A=218.
Organization and management of the plant safety evaluation of the VVER-440/230 units at Novovoronezh.
As part of the Soviet-Designed Reactor Safety (SDRS) element of the International Nuclear Safety Program (INSP), the US Department of Energy (US DOE) is funding a plant safety evaluation (PSE) project for the Novovoronezh Nuclear Power Plant (NvNPP). The Novovoronezh PSE Project is a multi-faceted project with participants from sixteen different international organizations from five different countries scattered across eleven time zones. The purpose of this project is to provide a thorough Probabilistic Risk Analysis (PRA) and Deterministic Safety Analysis (DSA) for Units 3 and 4 of the NvNPP. In addition, this project provides assistance to the operation organizations in meeting their international commitments in support of safety upgrades, and their regulatory requirements for the conduct of safety analyses. Managing this project is a complex process requiring numerous management tools, constant monitoring, and effective communication skills. Employing management tools to resolve unanticipated problems one of the keys to project success. The overall scope, programmatic context, objectives, project interactions, communications, practical hindrances, and lessons learned from the challenging performance of the PSE project are summarized in this paper.
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