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Sample records for affects subsequent fragmentation

  1. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Wednesday, 30 June 2010 00:00 Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research

  2. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters

  3. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters

  4. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters

  5. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters

  6. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters

  7. Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Site-Selective Ionization in Nanoclusters Affects Subsequent Fragmentation Print Understanding charge-transfer processes at the atomic level of nanoscale systems is of the utmost importance for designing nanodevices based on quantum-dot structures, nanotubes, or two-dimensional graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent ion fragmentation dynamics in nanoclusters

  8. Site-Selective Ionization in Nanoclusters Affects Subsequent...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    graphene sheets. Researchers from Western Michigan University, Berkeley Lab, and other international research facilities investigated charge-transfer processes and subsequent...

  9. Selectable fragmentation warhead

    SciTech Connect (OSTI)

    Bryan, Courtney S.; Paisley, Dennis L.; Montoya, Nelson I.; Stahl, David B.

    1993-01-01

    A selectable fragmentation warhead capable of producing a predetermined number of fragments from a metal plate, and accelerating the fragments toward a target. A first explosive located adjacent to the plate is detonated at selected number of points by laser-driven slapper detonators. In one embodiment, a smoother-disk and a second explosive, located adjacent to the first explosive, serve to increase acceleration of the fragments toward a target. The ability to produce a selected number of fragments allows for effective destruction of a chosen target.

  10. Selectable fragmentation warhead

    SciTech Connect (OSTI)

    Bryan, C.S.; Paisley, D.L.; Montoya, N.I.; Stahl, D.B.

    1992-12-31

    This report discusses a selectable fragmentation warhead which is capable of producing a predetermined number of fragments from a metal plate, and accelerating the fragments toward a target. A first explosive located adjacent to the plate is detonated at selected number of points by laser-driven slapper detonators. In one embodiment, a smoother-disk and a second explosive, located adjacent to the first explosive, serve to increase acceleration of the fragments toward a target. The ability to produce a selected number of fragments allows for effective destruction of a chosen target.

  11. Selectable fragmentation warhead

    SciTech Connect (OSTI)

    Bryan, C.S.; Paisley, D.L.; Montoya, N.I.; Stahl, D.B.

    1993-07-20

    A selectable fragmentation warhead is described comprising: a case having proximal and distal ends; a fragmenting plate mounted in said distal end of said casing; first explosive means cast adjacent to said fragmenting plate for creating a predetermined number of fragments from said fragmenting plate; three or more first laser-driven slapper detonators located adjacent to said first explosive means for detonating said first explosive means in a predetermined pattern; smoother-disk means located adjacent to said first means for accelerating said fragments; second explosive means cast adjacent to said smoother-disk means for further accelerating said fragments; at least one laser-driven slapper detonators located in said second explosive means; a laser located in said proximal end of said casing; optical fibers connecting said laser to said first and second laser-driven slapper detonators; and optical switch means located in series with said optical fibers connected to said plurality of first laser-driven slapper detonators for blocking or passing light from said laser to said plurality of first laser-driven slapper detonators.

  12. Fragment capture device

    DOE Patents [OSTI]

    Payne, Lloyd R.; Cole, David L.

    2010-03-30

    A fragment capture device for use in explosive containment. The device comprises an assembly of at least two rows of bars positioned to eliminate line-of-sight trajectories between the generation point of fragments and a surrounding containment vessel or asset. The device comprises an array of at least two rows of bars, wherein each row is staggered with respect to the adjacent row, and wherein a lateral dimension of each bar and a relative position of each bar in combination provides blockage of a straight-line passage of a solid fragment through the adjacent rows of bars, wherein a generation point of the solid fragment is located within a cavity at least partially enclosed by the array of bars.

  13. LANL analyzes meteor fragments nondestructively

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    LANL analyzes meteor fragments nondestructively LANL analyzes meteor fragments nondestructively Researchers and collaborators used the Los Alamos Neutron Science Center User Facility to perform novel compositional tomography characterizing small samples of the Chelyabinsk meteor. April 1, 2015 Chelyabinsk meteor fragment shown next to a 1-cm scale cube. Chelyabinsk meteor fragment shown next to a 1-cm scale cube. The team employed a range of LANSCE probes to analyze Chelyabinsk fragments and two

  14. Recovery of Depleted Uranium Fragments from Soil

    SciTech Connect (OSTI)

    Farr, C.P.; Alecksen, T.J.; Heronimus, R.S.; Simonds, M.H.; Farrar, D.R.; Baker, K.R.; Miller, M.L.

    2008-07-01

    A cost-effective method was demonstrated for recovering depleted uranium (DU) fragments from soil. A compacted clean soil pad was prepared adjacent to a pile of soil containing DU fragments. Soil from the contaminated pile was placed on the pad in three-inch lifts using conventional construction equipment. Each lift was scanned with an automatic scanning system consisting of an array of radiation detectors coupled to a detector positioning system. The data were downloaded into ArcGIS for data presentation. Areas of the pad exhibiting scaler counts above the decision level were identified as likely locations of DU fragments. The coordinates of these locations were downloaded into a PDA that was wirelessly connected to the positioning system. The PDA guided technicians to the locations where hand-held trowels and shovels were used to remove the fragments. After DU removal, the affected areas were re-scanned and the new data patched into the data base to replace the original data. This new data set along with soil sample results served as final status survey data. (authors)

  15. Fragmentation inside an identified jet

    SciTech Connect (OSTI)

    Procura, Massimiliano; Stewart, Iain W.

    2011-05-23

    Using Soft-Collinear Effective Theory (SCET) we derive factorization formulae for semi-inclusive processes where a light hadron h fragments from a jet whose invariant mass is measured. Our analysis yields a novel 'fragmenting jet function' G{sub i}{sup h}(s,z) that depends on the jet invariant mass {radical}(s), and on the fraction z of the large light-cone momentum components of the hadron and the parent parton i. We show that G{sub i}{sup h}(s,z) can be computed in terms of perturbatively calculable coefficients, J{sub ij}(s,z/x), integrated against standard non-perturbative fragmentation functions, D{sub j}{sup h}(x). Our analysis yields a simple replacement rule that allows any factorization theorem depending on a jet function J{sub i} to be converted to a semi-inclusive process with a fragmenting hadron h.

  16. Fission fragment driven neutron source

    DOE Patents [OSTI]

    Miller, Lowell G.; Young, Robert C.; Brugger, Robert M.

    1976-01-01

    Fissionable uranium formed into a foil is bombarded with thermal neutrons in the presence of deuterium-tritium gas. The resulting fission fragments impart energy to accelerate deuterium and tritium particles which in turn provide approximately 14 MeV neutrons by the reactions t(d,n).sup.4 He and d(t,n).sup.4 He.

  17. FRAGMENTATION IN THE FIRST GALAXIES

    SciTech Connect (OSTI)

    Safranek-Shrader, Chalence; Bromm, Volker; Milosavljevic, Milos

    2010-11-10

    Motivated by recent simulations of galaxy formation in which protogalaxies acquire their baryonic content through cold accretion, we study the gravitational fragmentation of cold streams flowing into a typical first galaxy. We use a one-zone hydrodynamical model to examine the thermal evolution of the gas flowing into a 10{sup 8} M{sub sun} dark matter halo at redshift z = 10. The goal is to gain an understanding of the expected fragmentation mass scale and thus the characteristic mass of the first population of stars to form by shock fragmentation. Our model accurately describes the chemical and thermal evolution of the gas as we are specifically concerned with how the chemical abundances and initial conditions of the low-density, metal-enriched, cold accretion streams that pass an accretion shock alter the cooling properties and tendency to fragment in the post-shock gas. Cold accretion flows are not shock heated at the virial radius but instead flow along high-baryonic-density filaments of the cosmic web and penetrate deep into the host halo of the protogalaxy. In this physical regime, if molecular cooling is absent because of a strong Lyman-Werner background, we find there to be a sharp drop in the fragmentation mass at a metallicity of Z {approx} 10{sup -4} Z{sub sun}. If, however, H{sub 2} and HD molecules are present, they dominate the cooling at T < 10{sup 4} K, and metallicity then has no effect on the fragmentation properties of the cold stream. For a solar abundance pattern of metallicity, O is the most effective metal coolant throughout the evolution, while for a pair instability supernova (PISN) metallicity yield, Si{sup +} is the most effective coolant. PISN abundance patterns also exhibit a slightly smaller critical metallicity. Dust grains are not included in our chemical model, but we argue that their inclusion would not significantly alter the results. We also find that this physical scenario allows for the formation of stellar clusters and large

  18. Polarized Photofission Fragment Angular Distributions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Photofission Fragment Angular Distributions of 232 Th and 238 U Jeromy Ryan Tompkins A dissertation submitted to the faculty of the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Physics and Astronomy. Chapel Hill 2012 Approved by: H. J. Karwowski M. W. Ahmed T. B. Clegg J. Engel F. Heitsch c O 2012 Jeromy Ryan Tompkins ALL RIGHTS RESERVED ii ABSTRACT JEROMY RYAN TOMPKINS: Polarized Photofission

  19. Fission fragment excited laser system

    DOE Patents [OSTI]

    McArthur, David A.; Tollefsrud, Philip B.

    1976-01-01

    A laser system and method for exciting lasing action in a molecular gas lasing medium which includes cooling the lasing medium to a temperature below about 150 K and injecting fission fragments through the lasing medium so as to preferentially excite low lying vibrational levels of the medium and to cause population inversions therein. The cooled gas lasing medium should have a mass areal density of about 5 .times. 10.sup.-.sup.3 grams/square centimeter, relaxation times of greater than 50 microseconds, and a broad range of excitable vibrational levels which are excitable by molecular collisions.

  20. Investigation of the fracture and fragmentation of explosively driven rings and cylinders

    SciTech Connect (OSTI)

    Goto, D M; Becker, R C; Orzechowski, T J; Springer, H K; Sunwoo, A J; Syn, C K

    2007-04-18

    Cylinders and rings fabricated from AerMet{reg_sign} 100 alloy and AISI 1018 steel have been explosively driven to fragmentation in order to determine the fracture strains for these materials under plane strain and uniaxial stress conditions. The phenomena associated with the dynamic expansion and subsequent break up of the cylinders are monitored with high-speed diagnostics. In addition, complementary experiments are performed in which fragments from the explosively driven cylinders are recovered and analyzed to determine the statistical distribution associated with the fragmentation process as well as to determine failure mechanisms. The data are used to determine relevant coefficients for the Hancock-McKenzie (Johnson-Cook) fracture model. Metallurgical analysis of the fragments provides information on damage and failure mechanisms.

  1. Complex fragment emission from hot compound nuclei

    SciTech Connect (OSTI)

    Moretto, L.G.

    1986-03-01

    The experimental evidence for compound nucleus emission of complex fragments at low energies is used to interpret the emission of the same fragments at higher energies. The resulting experimental picture is that of highly excited compound nuclei formed in incomplete fusion processes which decay statistically. In particular, complex fragments appear to be produced mostly through compound nucleus decay. In the appendix a geometric-kinematic theory for incomplete fusion and the associated momentum transfer is outlined. 10 refs., 19 figs.

  2. Fragmentation in rotating isothermal protostellar clouds

    SciTech Connect (OSTI)

    Bodenheimer, P.; Tohline, J.E.; Black, D.C.

    1980-01-01

    Results of an extensive set of 3-D hydrodynamic calculations that have been performed to investigate the susceptibility of rotating clouds to gravitational fragmentation are presented. (GHT)

  3. An Experimental Study Of Hydromagmatic Fragmentation Through...

    Open Energy Info (EERE)

    Experimental Study Of Hydromagmatic Fragmentation Through Energetic, Non-Explosive Magma-Water Mixing Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal...

  4. Investigation of Explosively Driven Fragmentation of Metals - Two Dimensional Fracture and Fragmentation of Metal Shells: Progress Report II

    SciTech Connect (OSTI)

    Grady, D

    2003-02-01

    High explosive enclosed by a metal case qualitatively describes an essential component of high energy systems of importance to the Department of Energy. Detonation of the high explosive causes intense transient pressure loading of the metal following arrival of normal or obliquely incident explosive detonation wave. Subsequent expansion and deformation of the metal case leads to eventual rupture and the opening of fractures and fissures. Details of the rupture process are critical to performance of the system. Consequently, it is essential that the material and kinematic issues governing the processes of dynamic loading and subsequent failure of an explosive-metal case component within a functioning system be adequately understood. Among the reasons are to quantify existing performance, characterize potential degradation of performance resulting from system aging, and optimizing or maintaining system performance through implementation of structural or material changes. The physical and engineering issues underlying this dynamic response and failure phenomena are not adequately understood. The purpose of the present program is to identify the key issues and develop theoretical, computational and experimental models needed to achieve a satisfactory theoretical and analysis framework for analysis of metal case failure in the explosive environment. Specific tasks within the present program include: (1) Models and theories currently being pursued based on physical principles of both the statistical fragmentation concepts of Mott and the energy-based concept of others show promise of providing the analytic and computational methodology capable of predicting explosion-induced fracture and fragmentation of metal components. Experimental studies initiated in the earlier effort offer promise to provide critical test data for validation. The present task shall involve the further refinement and development of the dynamic failure and fragmentation models and theories, and the

  5. Sizing of DNA fragments by flow cytometry

    SciTech Connect (OSTI)

    Johnson, M.E.; Goodwin, P.M.; Ambrose, W.P.; Martin, J.C.; Marrone, B.L.; Jett, J.H.; Keller, R.A.

    1993-02-01

    Individual, stained DNA fragments were sized using a modified flow cytometer with high sensitivity fluorescence detection. The fluorescent intercalating dye ethidium homodimer was used to stain stoichiometrically lambda phage DNA and a Kpn I digest of lambda DNA. Stained, individual fragments of DNA were passed through a low average power, focused, mode-locked laser beam, and the fluorescence from each fragment was collected and quantified. Time-gated detection was used to discriminate against Raman scattering from the water solvent. The fluorescence burst from each fragment was related directly to its length, thus providing a means to size small quantities of kilobase lengths of DNA quickly. Improvements of several orders of magnitude in analysis time and sample size over current gel electrophoresis techniques were realized. Fragments of 17.1,29.9, and 48.5 thousand base pairs were well resolved, and were sized in 164 seconds. Less than one pg of DNA was required for analysis. We have demonstrated sizing of individual, stained DNA fragments with resolution approaching that of gel electrophoresis for moderately large fragments, but with significant reductions in the analysis time and the amount of sample required. Furthermore, system response is linear with DNA fragment length, in contrast to the logarithmic response in gel electrophoresis. There exists the potential to perform this sizing using relatively simple instrumentation, i.e. a continuous wave laser of low power and current mode detection.

  6. Sizing of DNA fragments by flow cytometry

    SciTech Connect (OSTI)

    Johnson, M.E.; Goodwin, P.M.; Ambrose, W.P.; Martin, J.C.; Marrone, B.L.; Jett, J.H.; Keller, R.A.

    1993-01-01

    Individual, stained DNA fragments were sized using a modified flow cytometer with high sensitivity fluorescence detection. The fluorescent intercalating dye ethidium homodimer was used to stain stoichiometrically lambda phage DNA and a Kpn I digest of lambda DNA. Stained, individual fragments of DNA were passed through a low average power, focused, mode-locked laser beam, and the fluorescence from each fragment was collected and quantified. Time-gated detection was used to discriminate against Raman scattering from the water solvent. The fluorescence burst from each fragment was related directly to its length, thus providing a means to size small quantities of kilobase lengths of DNA quickly. Improvements of several orders of magnitude in analysis time and sample size over current gel electrophoresis techniques were realized. Fragments of 17.1,29.9, and 48.5 thousand base pairs were well resolved, and were sized in 164 seconds. Less than one pg of DNA was required for analysis. We have demonstrated sizing of individual, stained DNA fragments with resolution approaching that of gel electrophoresis for moderately large fragments, but with significant reductions in the analysis time and the amount of sample required. Furthermore, system response is linear with DNA fragment length, in contrast to the logarithmic response in gel electrophoresis. There exists the potential to perform this sizing using relatively simple instrumentation, i.e. a continuous wave laser of low power and current mode detection.

  7. Ultrafast kinetics subsequent to shock compression in an oxygen...

    Office of Scientific and Technical Information (OSTI)

    to shock compression in an oxygen-balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock ...

  8. Ultrafast kinetics subsequent to shock in an unreacted, oxygen...

    Office of Scientific and Technical Information (OSTI)

    shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock in an ...

  9. The Top Quark, Its Discovery, and Subsequent Research

    Office of Scientific and Technical Information (OSTI)

    The Top Quark, Its Discovery, and Subsequent Research Resources with Additional Information 'Ever since the existence of the bottom (or b) quark was inferred from the discovery of ...

  10. Bone fragments a body can make

    SciTech Connect (OSTI)

    Stout, S.D.; Ross, L.M. Jr. )

    1991-05-01

    Data obtained from various analytical techniques applied to a number of small bone fragments recovered from a crime scene were used to provide evidence for the occurrence of a fatality. Microscopic and histomorphometric analyses confirmed that the fragments were from a human skull. X-ray microanalysis of darkened areas on the bone fragments revealed a chemical signature that matched the chemical signature of a shotgun pellet recovered at the scene of the crime. The above findings supported the deoxyribonucleic acid (DNA) fingerprint evidence which, along with other evidence, was used to convict a man for the murder of his wife, even though her body was never recovered.

  11. Electroweak fragmentation functions for dark matter annihilation

    SciTech Connect (OSTI)

    Cavasonza, Leila Ali; Krämer, Michael; Pellen, Mathieu

    2015-02-18

    Electroweak corrections can play a crucial role in dark matter annihilation. The emission of gauge bosons, in particular, leads to a secondary flux consisting of all Standard Model particles, and may be described by electroweak fragmentation functions. To assess the quality of the fragmentation function approximation to electroweak radiation in dark matter annihilation, we have calculated the flux of secondary particles from gauge-boson emission in models with Majorana fermion and vector dark matter, respectively. For both models, we have compared cross sections and energy spectra of positrons and antiprotons after propagation through the galactic halo in the fragmentation function approximation and in the full calculation. Fragmentation functions fail to describe the particle fluxes in the case of Majorana fermion annihilation into light fermions: the helicity suppression of the lowest-order cross section in such models cannot be lifted by the leading logarithmic contributions included in the fragmentation function approach. However, for other classes of models like vector dark matter, where the lowest-order cross section is not suppressed, electroweak fragmentation functions provide a simple, model-independent and accurate description of secondary particle fluxes.

  12. V-201: Cisco Intrusion Prevention System SSP Fragmented Traffic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    201: Cisco Intrusion Prevention System SSP Fragmented Traffic Denial of Service Vulnerability V-201: Cisco Intrusion Prevention System SSP Fragmented Traffic Denial of Service ...

  13. Twist-3 fragmentation effects for ALT in light hadron production...

    Office of Scientific and Technical Information (OSTI)

    Twist-3 fragmentation effects for ALT in light hadron production from proton-proton collisions Title: Twist-3 fragmentation effects for ALT in light hadron production from...

  14. Fragmentation, underlying event and jet shapes at the Tevatron...

    Office of Scientific and Technical Information (OSTI)

    Conference: Fragmentation, underlying event and jet shapes at the Tevatron Citation Details In-Document Search Title: Fragmentation, underlying event and jet shapes at the Tevatron...

  15. There is no Silver Bullet: Regionalization and Market Fragmentation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Market Fragmentation in Greenhouse Gas Mitigation Strategies There is no Silver Bullet: Regionalization and Market Fragmentation in Greenhouse Gas Mitigation Strategies 2004 ...

  16. Nondetectability of restriction fragments and independence of DNA fragment sizes within and between loci in RFLP typing of DNA

    SciTech Connect (OSTI)

    Chakraborty, R.; Zhong, Y.; Jin, L. ); Budowle, B. )

    1994-08-01

    The authors provide experimental evidence showing that, during the restriction-enzyme digestion of DNA samples, some of the HaeIII-digested DNA fragments are small enough to prevent their reliable sizing on a Southern gel. As a result of such nondetectability of DNA fragments, individuals who show a single-band DNA profile at a VNTR locus may not necessarily be true homozygotes. In a population database, when the presence of such nondetectable alleles is ignored, they show that a pseudodependence of alleles within as well as across loci may occur. Using a known statistical method, under the hypothesis of independence of alleles within loci, they derive an efficient estimate of null allele frequency, which may be subsequently used for testing allelic independence within and across loci. The estimates of null allele frequencies, thus derived, are shown to agree with direct experimental data on the frequencies of HaeIII-null alleles. Incorporation of null alleles into the analysis of the forensic VNTR database suggests that the assumptions of allelic independence within and between loci are appropriate. In contrast, a failure to incorporate the occurrence of null alleles would provide a wrong inference regarding the independence of alleles within and between loci. 47 refs., 2 figs., 4 tabs.

  17. Ultrafast kinetics subsequent to shock in an unreacted, oxygen...

    Office of Scientific and Technical Information (OSTI)

    subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Armstrong, M R; Zaug, J M; Grant, C D; Crowhurst, J C; Bastea, S 75...

  18. Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced

    Office of Scientific and Technical Information (OSTI)

    mixture of nitromethane and hydrogen peroxide (Conference) | SciTech Connect kinetics subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Authors: Armstrong, M R ; Zaug, J M ; Grant, C D ; Crowhurst, J C ; Bastea, S Publication Date: 2014-06-24 OSTI Identifier: 1149544 Report Number(s):

  19. DNA fragment sizing and sorting by laser-induced fluorescence

    DOE Patents [OSTI]

    Hammond, Mark L.; Jett, James H.; Keller, Richard A.; Marrone, Babetta L.; Martin, John C.

    1996-01-01

    A method is provided for sizing DNA fragments using high speed detection systems, such as flow cytometry to determine unique characteristics of DNA pieces from a sample. In one characterization the DNA piece is fragmented at preselected sites to produce a plurality of DNA fragments. The DNA piece or the resulting DNA fragments are treated with a dye effective to stain stoichiometrically the DNA piece or the DNA fragments. The fluorescence from the dye in the stained fragments is then examined to generate an output functionally related to the number of nucleotides in each one of the DNA fragments. In one embodiment, the intensity of the fluorescence emissions from each fragment is linearly related to the fragment length. The distribution of DNA fragment sizes forms a characterization of the DNA piece for use in forensic and research applications.

  20. Fragmentation of massive dense cores down to ? 1000 AU: Relation between fragmentation and density structure

    SciTech Connect (OSTI)

    Palau, Aina; Girart, Josep M.; Estalella, Robert; Fuente, Asuncin; Fontani, Francesco; Snchez-Monge, lvaro; Commeron, Benoit; Hennebelle, Patrick; Busquet, Gemma; Bontemps, Sylvain; Zapata, Luis A.; Zhang, Qizhou; Di Francesco, James

    2014-04-10

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 ?m (or 1.2 mm in two cases) and the spectral energy distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. Even though the estimated fragmentation level is strictly speaking a lower limit, its relative value is significant and several trends could be explored with our data. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered the effects of rotational-to-gravitational energy ratio, non-thermal velocity dispersion, and turbulence mode on the density structure of the cores, and found that compressive turbulence seems to yield higher central densities. Finally, a possible explanation for the origin of cores with concentrated density profiles, which are the cores showing no fragmentation, could be related with a strong magnetic field, consistent with the outcome of radiation magnetohydrodynamic simulations.

  1. FRAGMENTATION AND SPREADING OF A METEOR-LIKE OBJECT

    SciTech Connect (OSTI)

    Park, Chul; Brown, Jeffrey D.

    2012-12-01

    The phenomenon of fragmentation and spreading of a high-speed flying object resembling a meteorite is studied experimentally and theoretically. Experimentally, a model made of graphite is launched in a ballistic range and is made to fragment and spread. The flow field produced by the cloud of the fragments is observed optically. The observed deceleration and spreading behavior is numerically reconstructed using computational-fluid-dynamic calculations, applying an improved meteoroid fragmentation theory. The existing meteoroid fragmentation theory is improved by introducing the hypothesis that the incubation process of the pressurized fluid permeating through the fragment precedes the splitting process. The incubation time is determined by the ratio of permeability of the fragment to the fluid's viscosity and is much longer than the time for splitting given by the existing theory. Agreement is obtained between the observed and calculated behavior of the fragment cloud by appropriately choosing this ratio.

  2. Collective flow properties of intermediate mass fragments and isospin effects in fragmentation at Fermi energies

    SciTech Connect (OSTI)

    Baran, V.; Zus, R.; Colonna, M.; Di Toro, M.

    2013-11-13

    Within a microscopic transport model (Stochastic Mean Field) we analyze the collective flow properties associated to the intermediate mass fragments produced in nuclear fragmentation. We study the transverse and elliptic flow parameters for each rank in mass hierarchy. The results are plotted for {sup 124}Sn + {sup 124}Sn systems at an energy of 50AMeV and for an impact parameter b=4fm. The correlation with the dynamics of the isospin degree of freedom is also discussed and the results are presented for the same systems.

  3. Aminoindazole PDK1 Inhibitors: A Case Study in Fragment-Based Drug Discovery

    SciTech Connect (OSTI)

    Medina, Jesus R.; Blackledge, Charles W.; Heerding, Dirk A.; Campobasso, Nino; Ward, Paris; Briand, Jacques; Wright, Lois; Axten, Jeffrey M.

    2012-05-29

    Fragment screening of phosphoinositide-dependent kinase-1 (PDK1) in a biochemical kinase assay afforded hits that were characterized and prioritized based on ligand efficiency and binding interactions with PDK1 as determined by NMR. Subsequent crystallography and follow-up screening led to the discovery of aminoindazole 19, a potent leadlike PDK1 inhibitor with high ligand efficiency. Well-defined structure-activity relationships and protein crystallography provide a basis for further elaboration and optimization of 19 as a PDK1 inhibitor.

  4. SWAMP+: multiple subsequence alignment using associative massive parallelism

    SciTech Connect (OSTI)

    Steinfadt, Shannon Irene [Los Alamos National Laboratory; Baker, Johnnie W [KENT STATE UNIV.

    2010-10-18

    A new parallel algorithm SWAMP+ incorporates the Smith-Waterman sequence alignment on an associative parallel model known as ASC. It is a highly sensitive parallel approach that expands traditional pairwise sequence alignment. This is the first parallel algorithm to provide multiple non-overlapping, non-intersecting subsequence alignments with the accuracy of Smith-Waterman. The efficient algorithm provides multiple alignments similar to BLAST while creating a better workflow for the end users. The parallel portions of the code run in O(m+n) time using m processors. When m = n, the algorithmic analysis becomes O(n) with a coefficient of two, yielding a linear speedup. Implementation of the algorithm on the SIMD ClearSpeed CSX620 confirms this theoretical linear speedup with real timings.

  5. Communication: Embedded fragment stochastic density functional theory

    SciTech Connect (OSTI)

    Neuhauser, Daniel; Baer, Roi; Rabani, Eran

    2014-07-28

    We develop a method in which the electronic densities of small fragments determined by Kohn-Sham density functional theory (DFT) are embedded using stochastic DFT to form the exact density of the full system. The new method preserves the scaling and the simplicity of the stochastic DFT but cures the slow convergence that occurs when weakly coupled subsystems are treated. It overcomes the spurious charge fluctuations that impair the applications of the original stochastic DFT approach. We demonstrate the new approach on a fullerene dimer and on clusters of water molecules and show that the density of states and the total energy can be accurately described with a relatively small number of stochastic orbitals.

  6. QCD at the Tevatron: Jets and fragmentation

    SciTech Connect (OSTI)

    V. Daniel Elvira

    2001-09-27

    At the Fermilab Tevatron energies, ({radical} s=1800 GeV and {radical} s = 630 GeV), jet production is the dominant process. During the period 1992-1996, the D0 and CDF experiments accumulated almost 100 pb{sup -1} of data and performed the most accurate jet production measurements up to this date. These measurements and the NLO-QCD theoretical predictions calculated during the last decade, have improved our understanding of QCD, our knowledge of the proton structure, and pushed the limit to the scale associated with quark compositeness to 2.4-2.7 TeV. In this paper, we present the most recent published and preliminary measurements on jet production and fragmentation by the D0 and CDF collaborations.

  7. Soft x-ray ionization induced fragmentation of glycine

    SciTech Connect (OSTI)

    Itl, E.; Kooser, K.; Rachlew, E.; Huels, M. A.; Kukk, E.

    2014-06-21

    X-ray absorption commonly involves dissociative core ionization producing not only momentum correlated charged fragments but also low- and high-energy electrons capable of inducing damage in living tissue. This gives a natural motivation for studying the core ionization induced fragmentation processes in biologically important molecules such as amino acids. Here the fragmentation of amino acid glycine following carbon 1s core ionization has been studied. Using photoelectron-photoion-photoion coincidence technique, a detailed analysis on fragmentation of the sample molecule into pairs of momentum correlated cations has been carried out. The main characteristics of core ionization induced fragmentation of glycine were found to be the rupture of the CC{sub ?} bond and the presence of the CNH{sub 2}{sup +} fragment.

  8. 1999 vadose zone monitoring plan and guidance for subsequent years

    SciTech Connect (OSTI)

    Horton, D.G.; Reidel, S.P.; Last, G.V.

    1998-08-01

    The US Department of Energy`s Hanford Site has the most diverse and largest amounts of radioactive waste in the US. The majority of the liquid waste was disposed to the soil column where much of it remains today. This document provides the rationale and general framework for vadose zone monitoring at cribs, ditches, trenches and other disposal facilities to detect new sources of contamination and track the movement of existing contamination in the vadose zone for the protection of groundwater. The document provides guidance for subsequent site-specific vadose zone monitoring plans and includes a brief description of past vadose monitoring activities (Chapter 3); the results of the Data Quality Objective process used for this plan (Chapter 4); a prioritization of liquid waste disposal sites for vadose monitoring (Chapter 5 and Appendix B); a general Monitoring and Analysis Plan (Chapter 6); a general Quality Assurance Project Plan (Appendix A), and a description of vadose monitoring activities planned for FY 1999 (Appendix C).

  9. Charge Prediction of Lipid Fragments in Mass Spectrometry

    SciTech Connect (OSTI)

    Schrom, Brian T.; Kangas, Lars J.; Ginovska, Bojana; Metz, Thomas O.; Miller, John H.

    2011-12-18

    An artificial neural network is developed for predicting which fragment is charged and which fragment is neutral for lipid fragment pairs produced from a liquid chromatography tandem mass spectrometry simulation process. This charge predictor is integrated into software developed at PNNL for in silico spectra generation and identification of metabolites known as Met ISIS. To test the effect of including charge prediction in Met ISIS, 46 lipids are used which show a reduction in false positive identifications when the charge predictor is utilized.

  10. Microscopic Calculation of Fission Fragment Energies for the...

    Office of Scientific and Technical Information (OSTI)

    these calculations also highlight the importance of local constraints on the fragments ... DOE Contract Number: W-7405-ENG-48 Resource Type: Technical Report Research Org: Lawrence ...

  11. Fission fragment charge and mass distributions in Pu 239 ( n...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Fission fragment charge and mass distributions in Pu 239 ( n , f ) in the adiabatic nuclear energy density functional theory Citation Details In-Document Search ...

  12. Interplay between compound and fragments aspects of nuclear fission...

    Office of Scientific and Technical Information (OSTI)

    aspects of nuclear fission and heavy-ion reaction Citation Details In-Document Search Title: Interplay between compound and fragments aspects of nuclear fission and ...

  13. Fragment-Based Exploration of Binding Site Flexibility in Mycobacteriu...

    Office of Scientific and Technical Information (OSTI)

    in Mycobacterium tuberculosis BioA Citation Details In-Document Search Title: Fragment-Based Exploration of Binding Site Flexibility in Mycobacterium tuberculosis BioA Authors: ...

  14. Restriction fragment length polymorphisms associated with substance P gene

    SciTech Connect (OSTI)

    de Miguel, C.; Bonner, T.; Detera-Wadleigh, S.

    1987-05-01

    Substance P (SP) is an important neuropepetide detected in a variety of locations in the central nervous system. Variations in SP content or SP receptors in psychiatric disorders have been described. Using SP clones as probes the authors have found three restriction fragment length polymorphisms (RFLPs) in the SP gene. The RFLPs are generated by digestion of genomic DNA with the MspI, and RsaI and NcoI restriction endonucleases. The MspI RFLP is detected by two genomic clones mapping to the 5' end of the gene while the RsaI and NcoI rFLPs are both detected by two genomic clones on the 3' end and also by a full-length cDNA clone of the gene. All three RFLPs are characterized by two alleles. For the MspI RFLP the frequency of both alleles is similar, for the Rsa I and NcoI RFLP one of the alleles is significantly more abundant than the other. These RFLPs are now being used to determine whether any of the alleles correlate with either schizophrenia or affective disorder.

  15. Optical selection and collection of DNA fragments

    DOE Patents [OSTI]

    Roslaniec, Mary C.; Martin, John C.; Jett, James H.; Cram, L. Scott

    1998-01-01

    Optical selection and collection of DNA fragments. The present invention includes the optical selection and collection of large (>.mu.g) quantities of clonable, chromosome-specific DNA from a sample of chromosomes. Chromosome selection is based on selective, irreversible photoinactivation of unwanted chromosomal DNA. Although more general procedures may be envisioned, the invention is demonstrated by processing chromosomes in a conventional flow cytometry apparatus, but where no droplets are generated. All chromosomes in the sample are first stained with at least one fluorescent analytic dye and bonded to a photochemically active species which can render chromosomal DNA unclonable if activated. After passing through analyzing light beam(s), unwanted chromosomes are irradiated using light which is absorbed by the photochemically active species, thereby causing photoinactivation. As desired chromosomes pass this photoinactivation point, the inactivating light source is deflected by an optical modulator; hence, desired chromosomes are not photoinactivated and remain clonable. The selection and photoinactivation processes take place on a microsecond timescale. By eliminating droplet formation, chromosome selection rates 50 times greater than those possible with conventional chromosome sorters may be obtained. Thus, usable quantities of clonable DNA from any source thereof may be collected.

  16. Complex fragment emission at low and high excitation energy

    SciTech Connect (OSTI)

    Moretto, L.G.

    1986-08-01

    Complex fragment emission has been certified as a compound nucleus process at low energies. An extension of the measurements to heavy ion reactions up to 50 MeV/u shows that most complex fragments are emitted by highly excited compound nuclei formed in incomplete fusion reactions. 12 refs., 26 figs.

  17. Science based stockpile stewardship, uncertainty quantification, and fission fragment beams

    SciTech Connect (OSTI)

    Stoyer, M A; McNabb, D; Burke, J; Bernstein, L A; Wu, C Y

    2009-09-14

    Stewardship of this nation's nuclear weapons is predicated on developing a fundamental scientific understanding of the physics and chemistry required to describe weapon performance without the need to resort to underground nuclear testing and to predict expected future performance as a result of intended or unintended modifications. In order to construct more reliable models, underground nuclear test data is being reanalyzed in novel ways. The extent to which underground experimental data can be matched with simulations is one measure of the credibility of our capability to predict weapon performance. To improve the interpretation of these experiments with quantified uncertainties, improved nuclear data is required. As an example, the fission yield of a device was often determined by measuring fission products. Conversion of the measured fission products to yield was accomplished through explosion code calculations (models) and a good set of nuclear reaction cross-sections. Because of the unique high-fluence environment of an exploding nuclear weapon, many reactions occurred on radioactive nuclides, for which only theoretically calculated cross-sections are available. Inverse kinematics reactions at CARIBU offer the opportunity to measure cross-sections on unstable neutron-rich fission fragments and thus improve the quality of the nuclear reaction cross-section sets. One of the fission products measured was {sup 95}Zr, the accumulation of all mass 95 fission products of Y, Sr, Rb and Kr (see Fig. 1). Subsequent neutron-induced reactions on these short lived fission products were assumed to cancel out - in other words, the destruction of mass 95 nuclides was more or less equal to the production of mass 95 nuclides. If a {sup 95}Sr was destroyed by an (n,2n) reaction it was also produced by (n,2n) reactions on {sup 96}Sr, for example. However, since these nuclides all have fairly short half-lives (seconds to minutes or even less), no experimental nuclear reaction

  18. Fast antibody fragment motion: flexible linkers act as entropic spring

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Stingaciu, Laura R.; Ivanova, Oxana; Ohl, Michael; Biehl, Ralf; Richter, Dieter

    2016-03-29

    A flexible linker region between three fragments allows antibodies to adjust their binding sites to an antigen or receptor. Using Neutron Spin Echo Spectroscopy we observed fragment motion on a timescale of 7 ns with motional amplitudes of about 1 nm relative to each other. The mechanistic complexity of the linker region can be described by a spring model with Brownian motion of the fragments in a harmonic potential. Displacements, timescale, friction and force constant of the underlying dynamics are accessed. The force constant exhibits a similar strength to an entropic spring, with friction of the fragment matching the unboundmore » state. The observed fast motions are fluctuations in pre-existing equilibrium configurations. In conclusion, the Brownian motion of domains in a harmonic potential is the appropriate model to examine functional hinge motions dependent on the structural topology and highlights the role of internal forces and friction to function.« less

  19. Fragment Yields Calculated in a Time-Dependent Microscopic Theory...

    Office of Scientific and Technical Information (OSTI)

    Fragment Yields Calculated in a Time-Dependent Microscopic Theory of Fission Citation ... Word Cloud More Like This Full Text preview image File size NAView Full Text View Full ...

  20. Microscopic Calculation of Fission Fragment Energies for the...

    Office of Scientific and Technical Information (OSTI)

    for the 239Pu(nth,f) Reaction Citation Details In-Document Search Title: Microscopic Calculation of Fission Fragment Energies for the 239Pu(nth,f) Reaction We calculate the ...

  1. There is no Silver Bullet: Regionalization and Market Fragmentation in

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Greenhouse Gas Mitigation Strategies | Department of Energy There is no Silver Bullet: Regionalization and Market Fragmentation in Greenhouse Gas Mitigation Strategies There is no Silver Bullet: Regionalization and Market Fragmentation in Greenhouse Gas Mitigation Strategies 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Joint Global Change Research Institute 2004_deer_stokes.pdf (661.01 KB) More Documents & Publications Analysis Activities at Pacific Northwest

  2. A microscopic theory of low energy fission: fragment properties

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Conference: A microscopic theory of low energy fission: fragment properties Citation Details In-Document Search Title: A microscopic theory of low energy fission: fragment properties Authors: Younes, W ; Gogny, D ; Schunck, N Publication Date: 2013-01-11 OSTI Identifier: 1062214 Report Number(s): LLNL-PROC-609985 DOE Contract Number: W-7405-ENG-48 Resource Type: Conference Resource Relation: Conference: Presented at: Fifth International Conference on Fission

  3. Preequilibrium Emission of Light Fragments in Spallation Reactions

    Office of Scientific and Technical Information (OSTI)

    (Conference) | SciTech Connect Preequilibrium Emission of Light Fragments in Spallation Reactions Citation Details In-Document Search Title: Preequilibrium Emission of Light Fragments in Spallation Reactions No abstract prepared. Authors: Kerby, Leslie M. [1] ; Mashnik, Stepan G. [1] ; Sierk, Arnold John [1] + Show Author Affiliations Los Alamos National Laboratory Publication Date: 2012-08-17 OSTI Identifier: 1049321 Report Number(s): LA-UR-12-22825 TRN: US1204458 DOE Contract Number:

  4. Anticipate-Affect

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Anticipate-Affect Anticipate-Affect Scientists are developing sophisticated modeling and research techniques to give them an advantage in their ability to anticipate and affect explosive-related threats or events. v Sophisticated modeling and research techniques to counter threats What conditions lead an individual or group toward committing political violence? Is it possible to accurately forecast who will become radicalized or even estimate when they might resort to violence? These and similar

  5. Basophile: Accurate Fragment Charge State Prediction Improves Peptide Identification Rates

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Dong; Dasari, Surendra; Chambers, Matthew C.; Holman, Jerry D.; Chen, Kan; Liebler, Daniel; Orton, Daniel J.; Purvine, Samuel O.; Monroe, Matthew E.; Chung, Chang Y.; et al

    2013-03-07

    In shotgun proteomics, database search algorithms rely on fragmentation models to predict fragment ions that should be observed for a given peptide sequence. The most widely used strategy (Naive model) is oversimplified, cleaving all peptide bonds with equal probability to produce fragments of all charges below that of the precursor ion. More accurate models, based on fragmentation simulation, are too computationally intensive for on-the-fly use in database search algorithms. We have created an ordinal-regression-based model called Basophile that takes fragment size and basic residue distribution into account when determining the charge retention during CID/higher-energy collision induced dissociation (HCD) of chargedmore » peptides. This model improves the accuracy of predictions by reducing the number of unnecessary fragments that are routinely predicted for highly-charged precursors. Basophile increased the identification rates by 26% (on average) over the Naive model, when analyzing triply-charged precursors from ion trap data. Basophile achieves simplicity and speed by solving the prediction problem with an ordinal regression equation, which can be incorporated into any database search software for shotgun proteomic identification.« less

  6. Basophile: Accurate Fragment Charge State Prediction Improves Peptide Identification Rates

    SciTech Connect (OSTI)

    Wang, Dong; Dasari, Surendra; Chambers, Matthew C.; Holman, Jerry D.; Chen, Kan; Liebler, Daniel; Orton, Daniel J.; Purvine, Samuel O.; Monroe, Matthew E.; Chung, Chang Y.; Rose, Kristie L.; Tabb, David L.

    2013-04-08

    In shotgun proteomics, database search algorithms rely on fragmentation models to predict fragment ions that should be observed for a given peptide sequence. The most widely used strategy (Naive model) is oversimplified, cleaving all peptide bonds with equal probability to produce fragments of all charges below that of the precursor ion. More accurate models, based on fragmentation simulation, are too computationally intensive for on-the-fly use in database search algorithms. We have created an ordinal-regression-based model called Basophile that takes fragment size and basic residue distribution into account when determining the charge retention during CID/higher-energy collision induced dissociation (HCD) of charged peptides. This model improves the accuracy of predictions by reducing the number of unnecessary fragments that are routinely predicted for highly-charged precursors. Basophile increased the identification rates by 26% (on average) over the Naive model, when analyzing triply-charged precursors from ion trap data. Basophile achieves simplicity and speed by solving the prediction problem with an ordinal regression equation, which can be incorporated into any database search software for shotgun proteomic identification.

  7. Feasibility of an antiproton catalyzed fission fragment rocket

    SciTech Connect (OSTI)

    Hdinger, D.S.

    1992-03-01

    The purpose of this project was to investigate the feasibility of an antiproton catalyzed fission fragment rocket (FFR). The FFR is characterized by the extraction of fission fragments from the fissile fuel, and the utilization of their kinetic energy for thrust generation. A significant drawback to previous FFR designs was the requirement to maintain a critical nuclear pile as the fission fragment source. The author examined the possibility of replacing the critical pile with a sub-critical pile driven by antiprotons. Recent experiments have revealed that antiprotons stimulate highly energetic fissions in {sup 238}U, with a neutron multiplicity of 13.7 neutrons per fission. This interaction was used as a throttled neutron source. The pile consisted of layers of fissile coated fibers which are designed to allow fission fragments to escape them, where the fragments collide with a fluid. The heated fluid is then ejected from the rocket to provide thrust. The calculations performed indicate that each antiproton injected into the pile can stimulate 8 or more fissions while maintaining a neutron multiplication of less than 0.4. Based on the results seen, the engine design presented is inadequate. Limitations introduced by the reaction fluid far outweigh the simplicity-of-design gained. Despite this, the basic idea of using the antiproton-U interaction as a source of spacecraft propulsion warrants further study.

  8. Radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect (OSTI)

    Reimus, M.A.H.; Hinckley, J.E.

    1998-12-31

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the convertor housing, failure of one fueled clad, and release of a small quantity of fuel.

  9. Radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect (OSTI)

    Reimus, M.A.; Hinckley, J.E.

    1998-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel. {copyright} {ital 1998 American Institute of Physics.}

  10. Radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect (OSTI)

    Reimus, M. A. H.; Hinckley, J. E.

    1998-01-15

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel.

  11. Fragmentation production of triply heavy baryons at the CERN LHC

    SciTech Connect (OSTI)

    Nobary, M.A. Gomshi; Sepahvand, R.

    2005-02-01

    The triply heavy baryons in the standard model formed in direct c and b quark fragmentation are the {omega}{sub ccc}, {omega}{sub ccb}, {omega}{sub cbb} and {omega}{sub bbb} baryons. We calculate their fragmentation functions in leading order of perturbative QCD. The universal fragmentation probabilities fall within the range of 10{sup -5}-10{sup -7}.We also evaluate their cross section at the LHC ({radical}(s)=14 TeV) using next-to-leading order matrix elements for heavy quark-antiquark pair production. We present the differential cross sections as functions of the transverse momentum as well as the total cross sections. They range from a few nb to a few pb.

  12. Apparatus and method for producing fragment-free openings

    DOE Patents [OSTI]

    Cherry, Christopher R.

    2001-01-01

    An apparatus and method for explosively penetrating hardened containers such as steel drums without producing metal fragmentation is disclosed. The apparatus can be used singularly or in combination with water disrupters and other disablement tools. The apparatus is mounted in close proximity to the target and features a main sheet explosive that is initiated at least three equidistant points along the sheet's periphery. A buffer material is placed between the sheet explosive and the target. As a result, the metallic fragments generated from the detonation of the detonator are attenuated so that no fragments from the detonator are transferred to the target. As a result, an opening can be created in containers such as steel drums through which access to the IED is obtained to defuse it with projectiles or fluids.

  13. Equilibrium and non-equilibrium emission of complex fragments

    SciTech Connect (OSTI)

    Bowman, D.R.

    1989-08-01

    Complex fragment emission (Z{gt}2) has been studied in the reactions of 50, 80, and 100 MeV/u {sup 139}La + {sup 12}C, and 80 MeV/u {sup 139}La + {sup 27}Al, {sup nat}Cu, and {sup 197}Au. Charge, angle, and energy distributions were measured inclusively and in coincidence with other complex fragments, and were used to extract the source rapidities, velocity distributions, and cross sections. The experimental emission velocity distributions, charge loss distributions, and cross sections have been compared with calculations based on statistical compound nucleus decay. The binary signature of the coincidence events and the sharpness of the velocity distributions illustrate the primarily 2-body nature of the {sup 139}La + {sup 12}C reaction mechanism between 50 and 100 MeV/u. The emission velocities, angular distributions, and absolute cross sections of fragments of 20{le}Z{le}35 at 50 MeV/u, 19{le}Z{le}28 at 80 MeV/u, and 17{le}Z{le}21 at 100 MeV/u indicate that these fragments arise solely from the binary decay of compound nuclei formed in incomplete fusion reactions in which the {sup 139}La projectile picks up about one-half of the {sup 12}C target. In the 80 MeV/u {sup 139}La + {sup 27}Al, {sup nat}Cu, and {sup 197}Au reactions, the disappearance of the binary signature in the total charge and velocity distributions suggests and increase in the complex fragment and light charged particle multiplicity with increasing target mass. As in the 80 and 100 MeV/u {sup 139}La + {sup 12}C reactions, the lighter complex fragments exhibit anisotropic angular distributions and cross sections that are too large to be explained exclusively by statistical emission. 143 refs., 67 figs.

  14. Interplay between compound and fragments aspects of nuclear fission and

    Office of Scientific and Technical Information (OSTI)

    heavy-ion reaction (Conference) | SciTech Connect Conference: Interplay between compound and fragments aspects of nuclear fission and heavy-ion reaction Citation Details In-Document Search Title: Interplay between compound and fragments aspects of nuclear fission and heavy-ion reaction The scission point in nuclear fission plays a special role where one-body system changes to two-body system. Inverse of this situation is realized in heavy-ion fusion reaction where two-body system changes to

  15. Signature of the Fragmentation of a Color Flux Tube

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wong, Cheuk-Yin

    2015-10-07

    The production of quark-antiquark pairs along a color flux tube precedes the fragmentation of the tube. Because of the local conservation of momentum and charge, the production of amore » $q$-$$\\bar q$$ pair will lead to correlations of adjacently produced mesons (mostly pions). Adjacently produced pions however can be signalled by the their rapidity difference $$\\Delta y$$ falling within the window of $$|\\Delta y | < 1/(dN_\\pi/dy)$$, on account of the space-time-rapidity ordering of produced pions in a flux tube fragmentation. Therefore, the local conservation of momentum will lead to a suppression of azimuthal two-pion correlation $$dN/(d\\Delta \\phi\\, d\\Delta y)$$ on the near side at $$(\\Delta \\phi, \\Delta y) \\sim 0$$, but an enhanced azimuthal correlation on the back-to-back, away side at $$(\\Delta \\phi$$$$\\sim$$$$ \\pi,\\Delta y$$$$\\sim$$0). Similarly, in a flux tube fragmentation, the local conservation of charge will forbid the production of like charge pions within $$|\\Delta y | < 1/(dN_\\pi/dy)$$, but there is no such prohibition for $$|\\Delta y| >1/(dN_\\pi/dy)$$. These properties may be used as the signature for the fragmentation of a color flux tube.« less

  16. Signature of the Fragmentation of a Color Flux Tube

    SciTech Connect (OSTI)

    Wong, Cheuk-Yin

    2015-10-07

    The production of quark-antiquark pairs along a color flux tube precedes the fragmentation of the tube. Because of the local conservation of momentum and charge, the production of a $q$-$\\bar q$ pair will lead to correlations of adjacently produced mesons (mostly pions). Adjacently produced pions however can be signalled by the their rapidity difference $\\Delta y$ falling within the window of $|\\Delta y | < 1/(dN_\\pi/dy)$, on account of the space-time-rapidity ordering of produced pions in a flux tube fragmentation. Therefore, the local conservation of momentum will lead to a suppression of azimuthal two-pion correlation $dN/(d\\Delta \\phi\\, d\\Delta y)$ on the near side at $(\\Delta \\phi, \\Delta y) \\sim 0$, but an enhanced azimuthal correlation on the back-to-back, away side at $(\\Delta \\phi$$\\sim$$ \\pi,\\Delta y$$\\sim$0). Similarly, in a flux tube fragmentation, the local conservation of charge will forbid the production of like charge pions within $|\\Delta y | < 1/(dN_\\pi/dy)$, but there is no such prohibition for $|\\Delta y| >1/(dN_\\pi/dy)$. These properties may be used as the signature for the fragmentation of a color flux tube.

  17. Fragment transition density method to calculate electronic coupling for excitation energy transfer

    SciTech Connect (OSTI)

    Voityuk, Alexander A.

    2014-06-28

    A general approach, the Fragment Transition Density (FTD) scheme, is introduced to estimate electronic coupling for excitation energy transfer in a molecular system. Within this method, the excitation energies and transition densities of the system are used to derive the coupling matrix element. The scheme allows one to treat systems where exciton donor and acceptor are close together and their exchange interaction and orbital overlap are significant. The FTD method can be applied in combination with any quantum mechanical approach to treat excited states of general nature including single-, double-, and higher excitations. Using FTD approach, we derive excitonic couplings for several systems computed with the CIS, TD DFT and MS-CASPT2 methods. In particular, it is shown that the estimated coupling values in DNA ?-stacks are strongly affected by the short-range electronic interaction of adjacent nucleobases.

  18. Systematics and fragmentation of low-lying electric dipole strength

    SciTech Connect (OSTI)

    Savran, D.; Fritzsche, M.; Mueller, S.; Pietralla, N.; Ponomarev, V. Yu.; Sonnabend, K.; Endres, J.; Hasper, J.; Zilges, A.

    2009-01-28

    We report on systematic investigations of low-lying electric dipole (E1) strength in atomic nuclei. Using the method of real photon scattering the dipole response of all stable N = 82 isotones has been measured with high resolution. In all cases a resonance like structure of E1 strength is observed in the energy region 5-8 MeV, which shows a strong fragmentation. The total integrated strength increases towards the proton poorer isotones, indicating a dependence of the total strength on the neutron-to-proton ratio. The experimental results are compared to microscopic calculations within the Quasi-particle Phonon Model (QPM). By including complex configurations of up to three phonons the calculation is able to reproduce also the fragmentation of the E1 strength and is in good agreement with the experimental observation.

  19. Transversity and Collins Fragmentation Functions: Towards a New Global Analysis

    SciTech Connect (OSTI)

    Anselmino, M.; Boglione, M.; Melis, S.; Prokudin, A.; D'Alesio, U.; Kotzinian, A.; Murgia, F.

    2009-08-04

    We present an update of a previous global analysis of the experimental data on azimuthal asymmetries in semi-inclusive deep inelastic scattering (SIDIS), from the HERMES and COMPASS Collaborations, and in e{sup +}e{sup -}{yields}h{sub 1}h{sub 2}X processes, from the Belle Collaboration. Compared to the first extraction, a more precise determination of the Collins fragmentation function and the transversity distribution function for u and d quarks is obtained.

  20. Modeling of laser ablation and fragmentation of human calculi

    SciTech Connect (OSTI)

    Gitomer, S.; Jones, R.D.; Howsare, C.

    1989-01-01

    The large-scale radiation-hydrodynamics computer code LASNEX, has been used to model experimental results in the laser ablation and fragmentation of renal and biliary calculi. Recent experiments have demonstrated laser ablation and fragmentation of human calculi in vitro and in vivo. In the interaction, laser light incident upon the calculus is of sufficient intensity to produce a plasma (a hot ionized gas). The physical picture which emerges is as follows. The plasma couples to acoustic and shear waves which then propagate through the dense stone material, causing spall and fracture by reflection from material discontinuities or boundaries. Experiments have thus far yielded data on the interaction against which models can be tested. Data on the following have been published: (1) light emission, (2) absorption and emission spectra, (3) fragmentation efficiency, (4) cavitation bubble dynamics and (5) mass removal. We have performed one dimensional simulations of the laser-matter interaction to elucidate the important physical mechanisms. We find that good quantitative fits between simulation and experiment are obtained for visible light emission, electron temperature, electron density, plasma pressure and cavitation bubble growth. With regard to mass removal, experiment and simulation are consistent with each other and give an excellent estimate of the ablation threshold. The modeling indicates that a very small ablation layer at the surface of the calculus is responsible for significant mass loss by fragmentation within the bulk of the calculus. With such quantitative fits in hand, we believe this type of modeling can now be applied to the study of other procedures involving plasma formation of interest to the medical community. 25 refs., 7 figs.

  1. Thermal initiation caused by fragment impact on cased explosives

    SciTech Connect (OSTI)

    Schnurr, N.M. )

    1989-01-01

    Numerical calculations have been used to predict the velocity threshold for thermal initiation of a cased explosive caused by fragment impact. A structural analysis code was used to determine temperature profiles and a thermal analysis code was used to calculate reaction rates. Results generated for the United States Air Force MK 82 bomb indicate that the velocity threshold for thermal initiation is slightly higher than that for the shock-to-detonation process. 8 refs., 5 figs., 2 tabs.

  2. Collision dynamics of proton with formaldehyde: Fragmentation and ionization

    SciTech Connect (OSTI)

    Wang, Jing; Gao, Cong-Zhang; Beijing Radiation Center, Beijing 100875 ; Calvayrac, Florent; Zhang, Feng-Shou; Beijing Radiation Center, Beijing 100875; Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000

    2014-03-28

    Using time-dependent density functional theory, applied to the valence electrons and coupled non-adiabatically to molecular dynamics of the ions, we study the ionization and fragmentation of formaldehyde in collision with a proton. Four different impact energies: 35 eV, 85 eV, 135 eV, and 300 eV are chosen in order to study the energy effect in the low energy region, and ten different incident orientations at 85 eV are considered for investigating the steric effect. Fragmentation ratios, single, double, and total electron ionization cross sections are calculated. For large impact parameters, these results are close to zero irrespective of the incident orientations due to a weak projectile-target interaction. For small impact parameters, the results strongly depend on the collision energy and orientation. We also give the kinetic energy releases and scattering angles of protons, as well as the cross section of different ion fragments and the corresponding reaction channels.

  3. Calculated fission-fragment yield systematics in the region 74

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Möller, Peter; Randrup, Jørgen

    2015-04-01

    Background: In the seminal experiment by Schmidt et al. [Nucl. Phys. A 665, 221 (2000)] in which fission-fragment charge distributions were obtained for 70 nuclides, asymmetric distributions were seen above nucleon number A ≈ 226 and symmetric ones below. Because asymmetric fission had often loosely been explained as a preference for the nucleus to always exploit the extra binding of fragments near ¹³²Sn it was assumed that all systems below A ≈ 226 would fission symmetrically because available isotopes do not have a proton-to-neutron Z/N ratio that allows division into fragments near ¹³²Sn. But the finding by Andreyev et al.more »[Phys. Rev. Lett. 105, 252502 (2010)] did not conform to this expectation because the compound system ¹⁸⁰Hg was shown to fission asymmetrically. It was suggested that this was a new type of asymmetric fission, because no strong shell effects occur for any possible fragment division. Purpose: We calculate a reference database for fission-fragment mass yields for a large region of the nuclear chart comprising 987 nuclides. A particular aim is to establish whether ¹⁸⁰Hg is part of a contiguous region of asymmetric fission, and if so, its extent, or if not, in contrast to the actinides, there are scattered smaller groups of nuclei that fission asymmetrically in this area of the nuclear chart. Methods: We use the by now well benchmarked Brownian shape-motion method and perform random walks on the previously calculated five-dimensional potential-energy surfaces. The calculated shell corrections are damped out with energy according to a prescription developed earlier. Results: We have obtained a theoretical reference database of fission-fragment mass yields for 987 nuclides. These results show an extended region of asymmetric fission with approximate extension 74 ≤ Z ≤ 85 and 100 ≤ N ≤ 120. The calculated yields are highly variable. We show 20 representative plots of these variable features and summarize the main

  4. Dissertation: Precompound Emission of Energetic Light Fragments in Spallation Reactions

    SciTech Connect (OSTI)

    Kerby, Leslie Marie

    2015-08-04

    Emission of light fragments (LF) from nuclear reactions is an open question. Different reaction mechanisms contribute to their production; the relative roles of each, and how they change with incident energy, mass number of the target, and the type and emission energy of the fragments is not completely understood. None of the available models are able to accurately predict emission of LF from arbitrary reactions. However, the ability to describe production of LF (especially at energies ≳ 30 MeV) from many reactions is important for different applications, such as cosmic-ray-induced Single Event Upsets (SEUs), radiation protection, and cancer therapy with proton and heavy-ion beams, to name just a few. The Cascade-Exciton Model (CEM) version 03.03 and the Los Alamos version of the Quark-Gluon String Model (LAQGSM) version 03.03 event generators in Monte Carlo N-Particle Transport Code version 6 (MCNP6) describe quite well the spectra of fragments with sizes up to ⁴He across a broad range of target masses and incident energies (up to ~ 5 GeV for CEM and up to ~ 1 TeV/A for LAQGSM). However, they do not predict the high energy tails of LF spectra heavier than ⁴He well. Most LF with energies above several tens of MeV are emitted during the precompound stage of a reaction. The current versions of the CEM and LAQGSM event generators do not account for precompound emission of LF larger than ⁴He. The aim of our work is to extend the precompound model in them to include such processes, leading to an increase of predictive power of LF-production in MCNP6. This entails upgrading the Modified Exciton Model currently used at the preequilibrium stage in CEM and LAQGSM. It also includes expansion and examination of the coalescence and Fermi break-up models used in the precompound stages of spallation reactions within CEM and LAQGSM. Extending our models to include emission of fragments heavier than ⁴He at the precompound stage has indeed provided results that have much

  5. Argonne Gas-filled Fragment Analyzer-AGFA

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Gas-filled Fragment Analyzer-AGFA Argonne National Laboratory B.B. Back, R.V.F. Janssens, W.F. Henning, T.L. Khoo, J.A. Nolen, D.H. Potterveld, G. Savard, D. Seweryniak Hebrew University, Jerusalem, Israel M. Paul University of Massachusetts Lowell P. Chowdhury, C.J. Lister University of Maryland W.B. Walters University of Edinburgh P.J. Woods Lawrence Berkeley National Laboratory K. Gregorich Oregon State University W. Loveland Date: February 11, 2013 Abstract As the premier stable-beam user

  6. Method of freezing living cells and tissues with improved subsequent survival

    DOE Patents [OSTI]

    Senkan, Selim M.; Hirsch, Gerald P.

    1980-01-01

    This invention relates to an improved method for freezing red blood cells, ther living cells, or tissues with improved subsequent survival, wherein constant-volume freezing is utilized that results in significantly improved survival compared with constant-pressure freezing; optimization is attainable through the use of different vessel geometries, cooling baths and warming baths, and sample concentrations.

  7. Accurate phylogenetic classification of DNA fragments based onsequence composition

    SciTech Connect (OSTI)

    McHardy, Alice C.; Garcia Martin, Hector; Tsirigos, Aristotelis; Hugenholtz, Philip; Rigoutsos, Isidore

    2006-05-01

    Metagenome studies have retrieved vast amounts of sequenceout of a variety of environments, leading to novel discoveries and greatinsights into the uncultured microbial world. Except for very simplecommunities, diversity makes sequence assembly and analysis a verychallenging problem. To understand the structure a 5 nd function ofmicrobial communities, a taxonomic characterization of the obtainedsequence fragments is highly desirable, yet currently limited mostly tothose sequences that contain phylogenetic marker genes. We show that forclades at the rank of domain down to genus, sequence composition allowsthe very accurate phylogenetic 10 characterization of genomic sequence.We developed a composition-based classifier, PhyloPythia, for de novophylogenetic sequence characterization and have trained it on adata setof 340 genomes. By extensive evaluation experiments we show that themethodis accurate across all taxonomic ranks considered, even forsequences that originate fromnovel organisms and are as short as 1kb.Application to two metagenome datasets 15 obtained from samples ofphosphorus-removing sludge showed that the method allows the accurateclassification at genus level of most sequence fragments from thedominant populations, while at the same time correctly characterizingeven larger parts of the samples at higher taxonomic levels.

  8. Isomeric signatures in the fragmentation of pyridazine and pyrimidine induced by fast ion impact

    SciTech Connect (OSTI)

    Wolff, Wania Luna, Hugo; Montenegro, Eduardo C.

    2015-07-28

    We present fast proton impact induced fragmentations of pyrimidine and pyridazine as an experimental resource to investigate isomeric signatures. Major isomeric imprints are identified for few fragment ions and differences of more than an order of magnitude for the cross sections of fragments of the same mass were measured. The observation of the molecular structure of these isomers gives no apparent indication for the reasons for such substantial differences. It is verified that the simple displacement of the position of one nitrogen atom strongly inhibits or favors the production of some ionic fragment species. The dependency of the fragmentation cross sections on the proton impact energy, investigated by means of time of flight mass spectroscopy and of a model calculation based in first order perturbation theory, allows us to disentangle the complex collision dynamics of the ionic fragments. The proton-induced fragmentation discriminates rather directly the association between a molecular orbital ionization and the fragment-ions creation and abundance, as well as how the redistribution of the energy imparted to the molecules takes place, triggering not only single but also double vacancy and leads to specific fragmentation pathways.

  9. Patterned Exfoliation of GaAs Based on Masked Helium Implantation and Subsequent Rapid Thermal Annealing

    SciTech Connect (OSTI)

    Woo, H. J.; Choi, H. W.; Kim, G. D.; Hong, W.; Kim, J. K.

    2009-03-10

    A method of patterning single crystal GaAs based on ion implantation induced selective area exfoliation is suggested. Samples were implanted with 200-500 keV helium ions to a fluence range of 2-4x10{sup 16} He{sup +}/cm{sup 2} at room temperature through masks of Ni mesh (40 {mu}m opening) or stainless steel wire (50 {mu}m in diameter), and subsequent rapid thermal annealing at 350-500{open_square} resulted in expulsion of ion beam exposed material. The influences of ion energy, ion fluence, implantation temperature, subsequent annealing conditions (temperature and ramp rate), and mask pattern and its orientation with GaAs lattice on the patterned exfoliation were examined.

  10. Fragmentation and Hadronization in e+e- Collisions

    SciTech Connect (OSTI)

    Muller, David

    2001-11-15

    We present a number of jet fragmentation and hadronization measurements in e{sup +}e{sup -} {yields} Z{sup 0} {yields} hadrons. The L3 collaboration has searched for pointlike color singlet radiation in multi-jet events, limiting any such contribution to rapidity gap events at the few percent level. ALEPH and SLD have measured production rates of a number of identified hadrons, including precise, full-coverage spectra of B hadrons. L3 and SLD have studied charged track and identified hadron production in heavy- and light-flavor events. OPAL has made a pioneering comparison of charged multiplicities between events of the three light flavors, u{bar u}, d{bar d} and s{bar s}.

  11. Charmed-hadron fragmentation functions from CERN LEP1 revisited

    SciTech Connect (OSTI)

    Kniehl, Bernd A.; Kramer, Gustav

    2006-08-01

    In Phys. Rev. D 58, 014014 (1998) and 71, 094013 (2005), we determined nonperturbative D{sup 0}, D{sup +}, D*{sup +}, D{sub s}{sup +}, and {lambda}{sub c}{sup +} fragmentation functions, both at leading and next-to-leading order in the MS factorization scheme, by fitting e{sup +}e{sup -} data taken by the OPAL Collaboration at CERN LEP1. The starting points for the evolution in the factorization scale {mu} were taken to be {mu}{sub 0}=2m{sub Q}, where Q=c, b. For the reader's convenience, in this paper, we repeat this analysis for {mu}{sub 0}=m{sub Q}, where the flavor thresholds of modern sets of parton density functions are located.

  12. Density functional theory based generalized effective fragment potential method

    SciTech Connect (OSTI)

    Nguyen, Kiet A. E-mail: ruth.pachter@wpafb.af.mil; Pachter, Ruth E-mail: ruth.pachter@wpafb.af.mil; Day, Paul N.

    2014-06-28

    We present a generalized Kohn-Sham (KS) density functional theory (DFT) based effective fragment potential (EFP2-DFT) method for the treatment of solvent effects. Similar to the original Hartree-Fock (HF) based potential with fitted parameters for water (EFP1) and the generalized HF based potential (EFP2-HF), EFP2-DFT includes electrostatic, exchange-repulsion, polarization, and dispersion potentials, which are generated for a chosen DFT functional for a given isolated molecule. The method does not have fitted parameters, except for implicit parameters within a chosen functional and the dispersion correction to the potential. The electrostatic potential is modeled with a multipolar expansion at each atomic center and bond midpoint using Stone's distributed multipolar analysis. The exchange-repulsion potential between two fragments is composed of the overlap and kinetic energy integrals and the nondiagonal KS matrices in the localized molecular orbital basis. The polarization potential is derived from the static molecular polarizability. The dispersion potential includes the intermolecular D3 dispersion correction of Grimme et al. [J. Chem. Phys. 132, 154104 (2010)]. The potential generated from the CAMB3LYP functional has mean unsigned errors (MUEs) with respect to results from coupled cluster singles, doubles, and perturbative triples with a complete basis set limit (CCSD(T)/CBS) extrapolation, of 1.7, 2.2, 2.0, and 0.5 kcal/mol, for the S22, water-benzene clusters, water clusters, and n-alkane dimers benchmark sets, respectively. The corresponding EFP2-HF errors for the respective benchmarks are 2.41, 3.1, 1.8, and 2.5 kcal/mol. Thus, the new EFP2-DFT-D3 method with the CAMB3LYP functional provides comparable or improved results at lower computational cost and, therefore, extends the range of applicability of EFP2 to larger system sizes.

  13. Factors Affecting PMU Installation Costs

    Broader source: Energy.gov (indexed) [DOE]

    ... information to improve the modeling, forecasting and controls of the grid Standards ... Department of Energy |September 2014 Factors Affecting PMU Installation Costs | Page 3 ...

  14. Origin of the narrow, single peak in the fission-fragment mass...

    Office of Scientific and Technical Information (OSTI)

    In the calculations, we minimize total energies by varying the deformations of the two fragments, with constraints on the mass quadrupole moment, and by keeping the neck radius ...

  15. Hitting the target: fragment screening with acoustic in situ co-crystallization of proteins plus fragment libraries on pin-mounted data-collection micromeshes

    SciTech Connect (OSTI)

    Yin, Xingyu; Scalia, Alexander; Leroy, Ludmila; Cuttitta, Christina M.; Polizzo, Gina M.; Ericson, Daniel L.; Roessler, Christian G.; Campos, Olven; Ma, Millie Y.; Agarwal, Rakhi; Jackimowicz, Rick; Allaire, Marc; Orville, Allen M.; Sweet, Robert M.; Soares, Alexei S.

    2014-05-01

    A method is presented for screening fragment libraries using acoustic droplet ejection to co-crystallize proteins and chemicals directly on micromeshes with as little as 2.5 nl of each component. This method was used to identify previously unreported fragments that bind to lysozyme, thermolysin, and trypsin. Acoustic droplet ejection (ADE) is a powerful technology that supports crystallographic applications such as growing, improving and manipulating protein crystals. A fragment-screening strategy is described that uses ADE to co-crystallize proteins with fragment libraries directly on MiTeGen MicroMeshes. Co-crystallization trials can be prepared rapidly and economically. The high speed of specimen preparation and the low consumption of fragment and protein allow the use of individual rather than pooled fragments. The Echo 550 liquid-handling instrument (Labcyte Inc., Sunnyvale, California, USA) generates droplets with accurate trajectories, which allows multiple co-crystallization experiments to be discretely positioned on a single data-collection micromesh. This accuracy also allows all components to be transferred through small apertures. Consequently, the crystallization tray is in equilibrium with the reservoir before, during and after the transfer of protein, precipitant and fragment to the micromesh on which crystallization will occur. This strict control of the specimen environment means that the crystallography experiments remain identical as the working volumes are decreased from the few microlitres level to the few nanolitres level. Using this system, lysozyme, thermolysin, trypsin and stachydrine demethylase crystals were co-crystallized with a small 33-compound mini-library to search for fragment hits. This technology pushes towards a much faster, more automated and more flexible strategy for structure-based drug discovery using as little as 2.5 nl of each major component.

  16. Reconnecting fragmented sturgeon populations in North American rivers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jager, Yetta; Forsythe, Patrick S.; McLaughlin, Robert L.; Joseph J. Cech, Jr.; Parsley, Michael; Elliott, Robert F.; Pracheil, Brenda M.

    2016-02-24

    The majority of large North American rivers are fragmented by dams that interrupt migrations of wide-ranging fishes like sturgeons. Reconnecting habitat is viewed as an important means of protecting sturgeon species in U.S. rivers because these species have lost between 5% and 60% of their historical ranges. Unfortunately, facilities designed to pass other fishes have rarely worked well for sturgeons. The most successful passage facilities were sized appropriately for sturgeons and accommodated bottom-oriented species. For upstream passage, facilities with large entrances, full-depth guidance systems, large lifts, or wide fishways without obstructions or tight turns worked well. However, facilitating upstream migrationmore » is only half the battle. Broader recovery for linked sturgeon populations requires safe round-trip passage involving multiple dams. The most successful downstream passage facilities included nature-like fishways, large canal bypasses, and bottom-draw sluice gates. We outline an adaptive approach to implementing passage that begins with temporary programs and structures and monitors success both at the scale of individual fish at individual dams and the scale of metapopulations in a river basin. The challenge will be to learn from past efforts and reconnect North American sturgeon populations in a way that promotes range expansion and facilitates population recovery.« less

  17. Three-body fragmentation of CO{sub 2} driven by intense laser pulses

    SciTech Connect (OSTI)

    Wu, Chengyin Liu, Yunquan; Gong, Qihuang; Wu, Cong; Fan, Yameng; Xie, Xiguo; Wang, Peng; Deng, Yongkai

    2015-03-28

    Dissociative ionization dynamics were studied experimentally for CO{sub 2} driven by intense laser pulses. Three-dimensional momentum vectors of correlated atomic ions were obtained for each three-body fragmentation event using triple ion coincidence measurement. Newton diagram demonstrated that three-body fragmentation of CO{sub 2}{sup n+} (n = 3-6) can occur through Coulomb explosion process and sequential fragmentation process depending on the fragmentation channels. The experimental data from these two processes were disentangled by using correlation diagram of correlated ions. Based on the accurate Coulomb explosion data, we reconstructed the bond angle distributions of CO{sub 2}{sup n+} at the moment of fragmentation, which are close to that of neutral CO{sub 2} before laser irradiation.

  18. Fragmentation of habitats used by neotropical migratory birds in Southern Appalachians and the neotropics

    SciTech Connect (OSTI)

    Pearson, S.M.; Dale, V.H.; Offerman, H.L. |

    1993-12-31

    Recent declines in North American breeding populations have sparked great concern over the effects of habitat fragmentation. Neotropical migrant birds use and are influenced by two biomes during a single life span. Yet assessment of the relative importance of changes in tropical wintering areas versus temperate breeding areas is complicated by regional variation in rates and extent of habitat change. Landscape-level measurements of forest fragmentation derived from remotely-sensed data provide a means to compare the patterns of habitat modification on the wintering and breeding grounds of migrant birds. This study quantifies patterns of forest fragmentation in the Southern Appalachian Mountains and tropical Amazon and relates these patterns to the resource needs of neotropical migrant birds. Study sites were selected from remotely-sensed images to represent a range of forest fragmentation (highly fragmented landscape to continuous forest).

  19. Methods for producing partially digested restriction DNA fragments and for producing a partially modified PCR product

    DOE Patents [OSTI]

    Wong, Kwong-Kwok

    2000-01-01

    The present invention is an improved method of making a partially modified PCR product from a DNA fragment with a polymerase chain reaction (PCR). In a standard PCR process, the DNA fragment is combined with starting deoxynucleoside triphosphates, a primer, a buffer and a DNA polymerase in a PCR mixture. The PCR mixture is then reacted in the PCR producing copies of the DNA fragment. The improvement of the present invention is adding an amount of a modifier at any step prior to completion of the PCR process thereby randomly and partially modifying the copies of the DNA fragment as a partially modified PCR product. The partially modified PCR product may then be digested with an enzyme that cuts the partially modified PCR product at unmodified sites thereby producing an array of DNA restriction fragments.

  20. Investigation of the reaction {sup 208}Pb({sup 18}O, f): Fragment spins and phenomenological analysis of the angular anisotropy of fission fragments

    SciTech Connect (OSTI)

    Rusanov, A. Ya. Adeev, G. D.; Itkis, M. G.; Karpov, A. V.; Nadtochy, P. N.; Pashkevich, V. V.; Pokrovsky, I. V.; Salamatin, V. S.; Chubarian, G. G.

    2007-10-15

    The average multiplicity of gamma rays emitted by fragments originating from the fission of {sup 226}Th nuclei formed via a complete fusion of {sup 18}O and {sup 208}Pb nuclei at laboratory energies of {sup 18}O projectile ions in the range E{sub lab} = 78-198.5 MeV is measured and analyzed. The total spins of fission fragments are found and used in an empirical analysis of the energy dependence of the anisotropy of these fragments under the assumption that their angular distributions are formed in the vicinity of the scission point. The average temperature of compound nuclei at the scission point and their average angular momenta in the entrance channel are found for this analysis. Also, the moments of inertia are calculated for this purpose for the chain of fissile thorium nuclei at the scission point. All of these parameters are determined at the scission point by means of three-dimensional dynamical calculations based on Langevin equations. A strong alignment of fragment spins is assumed in analyzing the anisotropy in question. In that case, the energy dependence of the anisotropy of fission fragments is faithfully reproduced at energies in excess of the Coulomb barrier (E{sub c.m.} - E{sub B} {>=} 30 MeV). It is assumed that, as the excitation energy and the angular momentum of a fissile nucleus are increased, the region where the angular distributions of fragments are formed is gradually shifted from the region of nuclear deformations in the vicinity of the saddle point to the region of nuclear deformations in the vicinity of the scission point, the total angular momentum of the nucleus undergoing fission being split into the orbital component, which is responsible for the anisotropy of fragments, and the spin component. This conclusion can be qualitatively explained on the basis of linear-response theory.

  1. Nucleation of nanocrystalline diamond by fragmentation of fullerene precursors.

    SciTech Connect (OSTI)

    Gruen, D. M.

    1998-05-04

    Growth of diamond films from C{sub 60}/Ar microwave discharges results in a nanocrystalline microstructure with crystallite sizes in the range 3-10 nm. Heterogeneous nucleation rates of 10{sup 10} cm{sup {minus}2} sec are required to account for the results. The nucleation mechanism presented here fulfills this requirement and is based on the insertion of carbon dimer, C{sub 2}, molecules, produced by fragmentation of C{sub 60}, into the n-bonded dimer rows of the reconstructed (100) surface of diamond. Density functional theory is used to calculate the energetic of C{sub 2} insertion into carbon clusters that model the (100) surface. The reaction of singlet C{sub 2} with the double bond of the C{sub 9}H{sub 12} cluster leads to either carbene structures or a cyclobutynelike structure. At the HF/6-31G* level, the carbene product has a C{sub 2v} structure, while at the B3LYP/6-31G* levels of theory, it has a C{sub s} structure with the inserted C{sub 2} tilted. No barrier for insertion into the C=C double bond of the C{sub 9}H{sub 12} cluster was found at the HF/6-31G* and B3LYP/6-31G* levels of theory. Thus, calculations including correlation energy and geometry optimization indicate that insertion of C{sub 2} into a C=C double bond leads to a large energy lowering, {approximately}120 kcal/mol for a C{sub 9}H{sub 12} cluster, and there is no barrier for insertion.

  2. Origin of the narrow, single peak in the fission-fragment mass distribution

    Office of Scientific and Technical Information (OSTI)

    for 258Fm (Journal Article) | SciTech Connect Origin of the narrow, single peak in the fission-fragment mass distribution for 258Fm Citation Details In-Document Search Title: Origin of the narrow, single peak in the fission-fragment mass distribution for 258Fm We discuss the origin of the narrowness of the single peak at mass-symmetric division in the fragment mass-yield curve for spontaneous fission of {sup 258}Fm. For this purpose, we employ the macroscopic-microscopic model and calculate

  3. Simultaneous knockdown of six non-family genes using a single synthetic RNAi fragment in Arabidopsis thaliana

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Czarnecki, Olaf; Bryan, Anthony C.; Jawdy, Sara S.; Yang, Xiaohan; Cheng, Zong-Ming; Chen, Jin-Gui; Tuskan, Gerald A.

    2016-02-17

    Genetic engineering of plants that results in successful establishment of new biochemical or regulatory pathways requires stable introduction of one or more genes into the plant genome. It might also be necessary to down-regulate or turn off expression of endogenous genes in order to reduce activity of competing pathways. An established way to knockdown gene expression in plants is expressing a hairpin-RNAi construct, eventually leading to degradation of a specifically targeted mRNA. Knockdown of multiple genes that do not share homologous sequences is still challenging and involves either sophisticated cloning strategies to create vectors with different serial expression constructs ormore » multiple transformation events that is often restricted by a lack of available transformation markers. Synthetic RNAi fragments were assembled in yeast carrying homologous sequences to six or seven non-family genes and introduced into pAGRIKOLA. Transformation of Arabidopsis thaliana and subsequent expression analysis of targeted genes proved efficient knockdown of all target genes. In conclusion, we present a simple and cost-effective method to create constructs to simultaneously knockdown multiple non-family genes or genes that do not share sequence homology. The presented method can be applied in plant and animal synthetic biology as well as traditional plant and animal genetic engineering.« less

  4. MCNP6 Simulation of Light and Medium Nuclei Fragmentation at Intermediate Energies

    SciTech Connect (OSTI)

    Mashnik, Stepan Georgievich; Kerby, Leslie Marie

    2015-08-24

    Fragmentation reactions induced on light and medium nuclei by protons and light nuclei of energies around 1 GeV/nucleon and below are studied with the Los Alamos transport code MCNP6 and with its CEM03.03 and LAQGSM03.03 event generators. CEM and LAQGSM assume that intermediate-energy fragmentation reactions on light nuclei occur generally in two stages. The first stage is the intranuclear cascade (INC), followed by the second, Fermi breakup disintegration of light excited residual nuclei produced after the INC. CEM and LAQGSM account also for coalescence of light fragments (complex particles) up to sup>4He from energetic nucleons emitted during INC. We investigate the validity and performance of MCNP6, CEM, and LAQGSM in simulating fragmentation reactions at intermediate energies and discuss possible ways of further improving these codes.

  5. Origin of the narrow, single peak in the fission-fragment mass...

    Office of Scientific and Technical Information (OSTI)

    fission-fragment mass distribution for 258Fm We discuss ... obtained from the single-particle wave-function densities. ... Full Text preview image File size NAView Full Text View ...

  6. Characterization of protein N-glycosylation by tandem mass spectrometry using complementary fragmentation techniques

    SciTech Connect (OSTI)

    Ford, Kristina L.; Zeng, Wei; Heazlewood, Joshua L.; Bacic, Antony

    2015-08-28

    The analysis of post-translational modifications (PTMs) by proteomics is regarded as a technically challenging undertaking. While in recent years approaches to examine and quantify protein phosphorylation have greatly improved, the analysis of many protein modifications, such as glycosylation, are still regarded as problematic. Limitations in the standard proteomics workflow, such as use of suboptimal peptide fragmentation methods, can significantly prevent the identification of glycopeptides. The current generation of tandem mass spectrometers has made available a variety of fragmentation options, many of which are becoming standard features on these instruments. Lastly, we have used three common fragmentation techniques, namely CID, HCD, and ETD, to analyze a glycopeptide and highlight how an integrated fragmentation approach can be used to identify the modified residue and characterize the N-glycan on a peptide.

  7. Orientation and alignment effects in ion-induced fragmentation of water: A triple coincidence study

    SciTech Connect (OSTI)

    Rajput, Jyoti; Safvan, C. P.

    2014-10-28

    The technique of recoil ion momentum spectroscopy is employed to determine the complete momentum vectors for three fragment dissociation channels, [D{sub 2}O]{sup (q+2)} ? (D{sup +} + D{sup +} + O{sup q+}) with q = 1, 2, or 3 formed in collisions of isolated water molecules with 450 keV Xe{sup 9+} ions. The kinetic energy released in each of these dissociation channels is measured and angular correlations between the fragment momenta are determined. From the angular correlations of the three fragment ions with the direction of the incoming beam, a strong anisotropy in the emission of recoil fragments is reported. It is inferred that the molecular plane prefers to lie orthogonal to the incoming beam direction with certain orientations being more preferred than others and a clear signature of non-coplanar dissociation is also observed.

  8. Characterization of protein N-glycosylation by tandem mass spectrometry using complementary fragmentation techniques

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ford, Kristina L.; Zeng, Wei; Heazlewood, Joshua L.; Bacic, Antony

    2015-08-28

    The analysis of post-translational modifications (PTMs) by proteomics is regarded as a technically challenging undertaking. While in recent years approaches to examine and quantify protein phosphorylation have greatly improved, the analysis of many protein modifications, such as glycosylation, are still regarded as problematic. Limitations in the standard proteomics workflow, such as use of suboptimal peptide fragmentation methods, can significantly prevent the identification of glycopeptides. The current generation of tandem mass spectrometers has made available a variety of fragmentation options, many of which are becoming standard features on these instruments. Lastly, we have used three common fragmentation techniques, namely CID, HCD,more » and ETD, to analyze a glycopeptide and highlight how an integrated fragmentation approach can be used to identify the modified residue and characterize the N-glycan on a peptide.« less

  9. Femtosecond spectroscopy probes the folding quality of antibody fragments expressed as GFP fusions in the cytoplasm

    SciTech Connect (OSTI)

    Didier, P. [Faculte de Pharmacie, UMR 7175, 74, route du Rhin, 67412 Illkirch (France); Weiss, E.; Sibler, A.-P. [Ecole Superieure de Biotechnologie de Strasbourg, UMR 7175, Boulevard Sebastien Brant, F-67412 Illkirch (France); Philibert, P.; Martineau, P. [Centre de recherche en cancerologie de Montpellier, UMR 5160, Val d'Aurelle-Paul Lamarque, 34298 Montpellier cedex 5 (France); Bigot, J.-Y. [Institut de Physique et Chimie des Materiaux de Strasbourg, UMR 7504, 23, rue du Loess, F-67037 Strasbourg (France); Guidoni, L. [Institut de Physique et Chimie des Materiaux de Strasbourg, UMR 7504, 23, rue du Loess, F-67037 Strasbourg (France); Laboratoire Materiaux et Phenomenes Quantiques, UMR 7162, Batiment Condorcet, 10 rue Alice Domon et Leonie Duquet, 75205 Paris cedex 13 (France)], E-mail: luca.guidoni@univ-paris-diderot.fr

    2008-02-22

    Time-resolved femtosecond spectroscopy can improve the application of green fluorescent proteins (GFPs) as protein-folding reporters. The study of ultrafast excited-state dynamics (ESD) of GFP fused to single chain variable fragment (scFv) antibody fragments, allowed us to define and measure an empirical parameter that only depends on the folding quality (FQ) of the fusion. This method has been applied to the analysis of genetic fusions expressed in the bacterial cytoplasm and allowed us to distinguish folded and thus functional antibody fragments (high FQ) with respect to misfolded antibody fragments. Moreover, these findings were strongly correlated to the behavior of the same scFvs expressed in animal cells. This method is based on the sensitivity of the ESD to the modifications in the tertiary structure of the GFP induced by the aggregation state of the fusion partner. This approach may be applicable to the study of the FQ of polypeptides over-expressed under reducing conditions.

  10. Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme

    SciTech Connect (OSTI)

    Theophilou, Iris; Tassi, M.; Thanos, S.

    2014-04-28

    Photoinduced charge-transfer processes play a key role for novel photovoltaic phenomena and devices. Thus, the development of ab initio methods that allow for an accurate and computationally inexpensive treatment of charge-transfer excitations is a topic that nowadays attracts a lot of scientific attention. In this paper we extend an approach recently introduced for the description of single and double excitations [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013); M. Tassi, I. Theophilou, and S. Thanos, J. Chem. Phys. 138, 124107 (2013)] to allow for the description of intermolecular charge-transfer excitations. We describe an excitation where an electron is transferred from a donor system to an acceptor one, keeping the excited state orthogonal to the ground state and avoiding variational collapse. These conditions are achieved by decomposing the space spanned by the Hartree-Fock (HF) ground state orbitals into four subspaces: The subspace spanned by the occupied orbitals that are localized in the region of the donor molecule, the corresponding for the acceptor ones and two more subspaces containing the virtual orbitals that are localized in the neighborhood of the donor and the acceptor, respectively. Next, we create a Slater determinant with a hole in the subspace of occupied orbitals of the donor and a particle in the virtual subspace of the acceptor. Subsequently we optimize both the hole and the particle by minimizing the HF energy functional in the corresponding subspaces. Finally, we test our approach by calculating the lowest charge-transfer excitation energies for a set of tetracyanoethylene-hydrocarbon complexes that have been used earlier as a test set for such kind of excitations.

  11. A Planning Tool for Estimating Waste Generated by a Radiological Incident and Subsequent Decontamination Efforts - 13569

    SciTech Connect (OSTI)

    Boe, Timothy; Lemieux, Paul; Schultheisz, Daniel; Peake, Tom; Hayes, Colin

    2013-07-01

    Management of debris and waste from a wide-area radiological incident would probably constitute a significant percentage of the total remediation cost and effort. The U.S. Environmental Protection Agency's (EPA's) Waste Estimation Support Tool (WEST) is a unique planning tool for estimating the potential volume and radioactivity levels of waste generated by a radiological incident and subsequent decontamination efforts. The WEST was developed to support planners and decision makers by generating a first-order estimate of the quantity and characteristics of waste resulting from a radiological incident. The tool then allows the user to evaluate the impact of various decontamination/demolition strategies on the waste types and volumes generated. WEST consists of a suite of standalone applications and Esri{sup R} ArcGIS{sup R} scripts for rapidly estimating waste inventories and levels of radioactivity generated from a radiological contamination incident as a function of user-defined decontamination and demolition approaches. WEST accepts Geographic Information System (GIS) shape-files defining contaminated areas and extent of contamination. Building stock information, including square footage, building counts, and building composition estimates are then generated using the Federal Emergency Management Agency's (FEMA's) Hazus{sup R}-MH software. WEST then identifies outdoor surfaces based on the application of pattern recognition to overhead aerial imagery. The results from the GIS calculations are then fed into a Microsoft Excel{sup R} 2007 spreadsheet with a custom graphical user interface where the user can examine the impact of various decontamination/demolition scenarios on the quantity, characteristics, and residual radioactivity of the resulting waste streams. (authors)

  12. V-201: Cisco Intrusion Prevention System SSP Fragmented Traffic Denial of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Service Vulnerability | Department of Energy 1: Cisco Intrusion Prevention System SSP Fragmented Traffic Denial of Service Vulnerability V-201: Cisco Intrusion Prevention System SSP Fragmented Traffic Denial of Service Vulnerability July 19, 2013 - 6:00am Addthis PROBLEM: Several vulnerabilities were reported in Cisco Intrusion Prevention System PLATFORM: Cisco ASA 5500-X Series Adaptive Security Appliances Cisco Intrusion Prevention System (IPS) 7.1 ABSTRACT: A vulnerability in the

  13. Fragment Yields Calculated in a Time-Dependent Microscopic Theory of

    Office of Scientific and Technical Information (OSTI)

    Fission (Technical Report) | SciTech Connect Fragment Yields Calculated in a Time-Dependent Microscopic Theory of Fission Citation Details In-Document Search Title: Fragment Yields Calculated in a Time-Dependent Microscopic Theory of Fission Authors: Younes, W ; Gogny, D Publication Date: 2012-09-28 OSTI Identifier: 1053671 Report Number(s): LLNL-TR-586678 DOE Contract Number: W-7405-ENG-48 Resource Type: Technical Report Research Org: Lawrence Livermore National Laboratory (LLNL),

  14. Notices Affected Public: Individuals and

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    3 Federal Register / Vol. 76, No. 23 / Thursday, February 3, 2011 / Notices Affected Public: Individuals and households; not-for-profit institutions; State, Local, or Tribal Government, State Educational Agencies or Local Educational Agencies. Total Estimated Number of Annual Responses: 22,760. Total Estimated Number of Annual Burden Hours: 8,725. Abstract: The study is being conducted as part of the National Assessment of Title I, mandated by Title I, Part E, Section 1501 of the Elementary and

  15. Statewide Power Problems May Affect SSRL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Statewide Power Problems May Affect SSRL The power crisis affecting California and the northwestern US may have some implication for SSRL users during the current run. As the...

  16. Resonance enhanced multiphoton and single-photon ionization of molecules and molecular fragments. Final report, May 1993--April 1997

    SciTech Connect (OSTI)

    McKoy, V.

    1998-09-01

    Resonance enhanced multiphoton ionization (REMPI) utilizes pulsed laser radiation to prepare a molecule in an excited state via absorption of one or more photons and to subsequently ionize that level before it decays. A remarkable feature of REMPI is that the very narrow bandwidth of laser radiation makes it possible to select a specific rotational level in the initial (ground) state and to prepare the excited state of interest in a single rotational level. Thus, by suitable choice of the excitation step, it is possible to selectively ionize a species that may be present. The key objective of the effort is to carry out quantitative studies of REMPI of molecules and molecular fragments, as well as of single-photon ionization of these species by coherent VUV radiation, in order to provide a robust description of significant spectral features of interest in related experiments and needed insight into the underlying dynamics of these spectra. A major focus of the effort is joint theoretical and experimental studies of these ion rotational distributions which are being widely studied by the zero-kinetic-energy (ZEKE) technique. This technique, which is based on the detection of photoelectrons resulting from pulsed-field ionization of very high Rydberg states lying just below an ion threshold, makes it possible to obtain cation distributions with subwavenumber resolution. The unprecedented resolution of this ZEKE technique is opening up entirely new vistas in studies of photoionization dynamics, ion spectroscopy, and state-selected ion-molecule reactions. Emerging applications built on the ultra-high resolution of this technique include its use for accurate determination of thermochemically important ionization energies, for characterization of ion rovibrational level structure of large organic molecules, of elemental clusters, and of weakly bound molecular complexes, for probing reactive fragments, and for pump-probe photoelectron studies of wavepacket dynamics. This

  17. DYNAMICS OF LARGE FRAGMENTS IN THE TAIL OF ACTIVE ASTEROID P/2010 A2

    SciTech Connect (OSTI)

    Agarwal, Jessica; Jewitt, David; Weaver, Harold

    2013-05-20

    We examine the motions of large fragments at the head of the dust tail of the active asteroid P/2010 A2. In previous work, we showed that these fragments were ejected from the primary nucleus in early 2009, either following a hypervelocity impact or by rotationally induced breakup. Here, we follow their positions through a series of Hubble Space Telescope images taken during the first half of 2010. The orbital evolution of each fragment allows us to constrain its velocity relative to the main nucleus after leaving its sphere of gravitational influence. We find that the fragments constituting a prominent X-shaped tail feature were emitted in a direction opposite to the motion of the asteroid and toward the south of its orbital plane. Derived emission velocities of these primary fragments range between 0.02 and 0.3 m s{sup -1}, comparable to the {approx}0.08 m s{sup -1} gravitational escape speed from the nucleus. Their sizes are on the order of decimeters or larger. We obtain the best fits to our data with ejection velocity vectors lying in a plane that includes the nucleus. This may suggest that the cause of the disruption of P/2010 A2 is rotational breakup.

  18. Fragmentation and systematics of the pygmy dipole resonance in the stable N=82 isotones

    SciTech Connect (OSTI)

    Savran, D.; Loeher, B.; Elvers, M.; Endres, J.; Zilges, A.; Fritzsche, M.; Pietralla, N.; Ponomarev, V. Yu.; Romig, C.; Schnorrenberger, L.; Sonnabend, K.

    2011-08-15

    The low-lying electric dipole (E1) strength in the semimagic nucleus {sup 136}Xe has been measured, which finalizes the systematic survey to investigate the so-called pygmy dipole resonance (PDR) in all stable even N=82 isotones with the method of nuclear resonance fluorescence using real photons in the entrance channel. In all cases, a fragmented resonance-like structure of E1 strength is observed in the energy region 5-8 MeV. An analysis of the fragmentation of the strength reveals that the degree of fragmentation decreases toward the proton-deficient isotones, while the total integrated strength increases, indicating a dependence of the total strength on the neutron-to-proton ratio. The experimental results are compared to microscopic calculations within the quasiparticle phonon model. The calculation includes complex configurations of up to three phonons and is able to reproduce also the fragmentation of the E1 strength, which allows us to draw conclusions on the damping of the PDR. Calculations and experimental data are in good agreement on the degree of fragmentation and also on the integrated strength if the sensitivity limit of the experiments is taken into account.

  19. A Predictive Model of Fragmentation using Adaptive Mesh Refinement and a Hierarchical Material Model

    SciTech Connect (OSTI)

    Koniges, A E; Masters, N D; Fisher, A C; Anderson, R W; Eder, D C; Benson, D; Kaiser, T B; Gunney, B T; Wang, P; Maddox, B R; Hansen, J F; Kalantar, D H; Dixit, P; Jarmakani, H; Meyers, M A

    2009-03-03

    Fragmentation is a fundamental material process that naturally spans spatial scales from microscopic to macroscopic. We developed a mathematical framework using an innovative combination of hierarchical material modeling (HMM) and adaptive mesh refinement (AMR) to connect the continuum to microstructural regimes. This framework has been implemented in a new multi-physics, multi-scale, 3D simulation code, NIF ALE-AMR. New multi-material volume fraction and interface reconstruction algorithms were developed for this new code, which is leading the world effort in hydrodynamic simulations that combine AMR with ALE (Arbitrary Lagrangian-Eulerian) techniques. The interface reconstruction algorithm is also used to produce fragments following material failure. In general, the material strength and failure models have history vector components that must be advected along with other properties of the mesh during remap stage of the ALE hydrodynamics. The fragmentation models are validated against an electromagnetically driven expanding ring experiment and dedicated laser-based fragmentation experiments conducted at the Jupiter Laser Facility. As part of the exit plan, the NIF ALE-AMR code was applied to a number of fragmentation problems of interest to the National Ignition Facility (NIF). One example shows the added benefit of multi-material ALE-AMR that relaxes the requirement that material boundaries must be along mesh boundaries.

  20. Summary of the oil shale fragmentation program at Anvil Points Mine, Colorado

    SciTech Connect (OSTI)

    Dick, R.D.; Young, C.; Fourney, W.L.

    1984-01-01

    During 1981 and 1982, an extensive oil shale fragmentation research program was conducted at the Anvil Points Mine near Rifle, Colorado. The primary goals were to investigate factors involved for adequate fragmentation of oil shale and to evaluate the feasibility of using the modified in situ retort (MIS) method for recovery of oil from oil shale. The test program included single-deck, single-borehole tests to obtain basic fragmentation data; multiple-borehole, multiple-deck explosive tests to evaluate practical aspects for developing an in situ retort; and the development of a variety of instrumentation techniques to diagnose the blasting event. This paper will present an outline of the field program, the type of instrumentation used, some typical results from the instrumentation, and a discussion of explosive engineering problems encountered over the course of the program. 4 references, 21 figures, 1 table.

  1. An innovative platform for quick and flexible joining of assorted DNA fragments

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    De Paoli, Henrique Cestari; Tuskan, Gerald A.; Yang, Xiaohan

    2016-01-13

    Successful synthetic biology efforts rely on conceptual and experimental designs in combination with testing of multi-gene constructs. Despite recent progresses, several limitations still hinder the ability to flexibly assemble and collectively share different types of DNA segments. We describe an advanced system for joining DNA fragments from a universal library that automatically maintains open reading frames (ORFs) and does not require linkers, adaptors, sequence homology, amplification or mutation (domestication) of fragments in order to work properly. Moreover, we find that this system, which is enhanced by a unique buffer formulation, provides unforeseen capabilities for testing, and sharing, complex multi-gene circuitrymore » assembled from different DNA fragments.« less

  2. A method to calculate fission-fragment yields Y(Z,N) versus proton and

    Office of Scientific and Technical Information (OSTI)

    neutron number in the Brownian shape-motion model (Journal Article) | SciTech Connect A method to calculate fission-fragment yields Y(Z,N) versus proton and neutron number in the Brownian shape-motion model Citation Details In-Document Search This content will become publicly available on December 23, 2016 Title: A method to calculate fission-fragment yields Y(Z,N) versus proton and neutron number in the Brownian shape-motion model In this study, we propose a method to calculate the

  3. Reexamination of fission fragment angular distributions and the fission process: Formalism

    SciTech Connect (OSTI)

    Bond, P.D.

    1985-08-01

    The theory of fission fragment angular distributions is examined and the universally used expression is found to be valid only under restrictive assumptions. A more general angular distribution formula is derived and applied to recent data of high spin systems. At the same time it is shown that the strong anisotropies observed from such systems can be understood without changing the essential basis of standard fission theory. The effects of reaction mechanisms other than complete fusion on fission fragment angular distributions are discussed and possible angular distribution signatures of noncompound nucleus formation are mentioned.

  4. BRIGHT HOT IMPACTS BY ERUPTED FRAGMENTS FALLING BACK ON THE SUN: UV REDSHIFTS IN STELLAR ACCRETION

    SciTech Connect (OSTI)

    Reale, F.; Orlando, S.; Testa, P.; Landi, E.; Schrijver, C. J.

    2014-12-10

    A solar eruption after a flare on 2011 June 7 produced EUV-bright impacts of fallbacks far from the eruption site, observed with the Solar Dynamics Observatory. These impacts can be taken as a template for the impact of stellar accretion flows. Broad redshifted UV lines have been commonly observed in young accreting stars. Here we study the emission from the impacts in the Atmospheric Imaging Assembly's UV channels and compare the inferred velocity distribution to stellar observations. We model the impacts with two-dimensional hydrodynamic simulations. We find that the localized UV 1600 emission and its timing with respect to the EUV emission can be explained by the impact of a cloud of fragments. The first impacts produce strong initial upflows. The following fragments are hit and shocked by these upflows. The UV emission comes mostly from the shocked front shell of the fragments while they are still falling, and is therefore redshifted when observed from above. The EUV emission instead continues from the hot surface layer that is fed by the impacts. Fragmented accretion can therefore explain broad redshifted UV lines (e.g., C IV 1550 ) to speeds around 400km s{sup 1} observed in accreting young stellar objects.

  5. Effects of quadrupole vibration of the fragments on. mu. - final state probabilities

    SciTech Connect (OSTI)

    Zheng Guo-tong; Wang Yan-sen; Yuan Zu-shu; Qiu Zhi-hong

    1988-01-01

    The muon final-state probabilities after muon-induced fission of /sup 238/U are calculated by using the LCAO (Linear Combination of Atomic Orbital) method. The ordinary viscosity of the fissioning nucleus, the deformations and quadrupole vibrations of the two fragments are taken into account. The calculated results are compared with those obtained by neglecting the quadrupole vibration

  6. Development of position-sensitive time-of-flight spectrometer for fission fragment research

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Arnold, C. W.; Tovesson, F.; Meierbachtol, K.; Bredeweg, T.; Jandel, M.; Jorgenson, H. J.; Laptev, A.; Rusev, G.; Shields, D. W.; White, M.; et al

    2014-07-09

    A position-sensitive, high-resolution time-of-flight detector for fission fragments has been developed. The SPectrometer for Ion DEtermination in fission Research (SPIDER) is a 2E–2v spectrometer designed to measure the mass of light fission fragments to a single mass unit. The time pick-off detector pairs to be used in SPIDER have been tested with α-particles from 229Th and its decay chain and α-particles and spontaneous fission fragments from 252Cf. Each detector module is comprised of thin electron conversion foil, electrostatic mirror, microchannel plates, and delay-line anodes. Particle trajectories on the order of 700 mm are determined accurately to within 0.7 mm. Flightmore » times were measured with 250 ps resolution FWHM. Computed particle velocities are accurate to within 0.06 mm/ns corresponding to a precision of 0.5%. As a result, an ionization chamber capable of 400 keV energy resolution coupled with the velocity measurements described here will pave the way for modestly efficient measurements of light fission fragments with unit mass resolution.« less

  7. Application of a damage model for rock fragmentation to the Straight Creek Mine blast experiments

    SciTech Connect (OSTI)

    Thorne, B.J.

    1991-09-01

    Early attempts at estimation of stress wave damage due to blasting by use of finite element calculations met with limited success due to numerical instabilities that prevented calculations from being carried past the fragmentation limit. More recently, the improved damage model PRONTO has allowed finite element calculations which remain stable and yield good agreement between calculated fragmented regions and excavated crater profiles for blasting experiments in granite. Application of this damage model to blast experiments at the Straight Creek Mine in Bell County, Kentucky were complicated by anisotropic conditions and uncertainties in material properties. It appears that significant modifications to the damage model and extensive material testing may be necessary in order to estimate damage in these anisotropic materials. 18 refs., 18 figs.

  8. Explosive fragmentation of oil shale: Results from Colony and Anvil Points Mines, Colorado

    SciTech Connect (OSTI)

    Dick, R.D.; Fourney, W.L.; Young, C. III

    1992-12-31

    From 1978 through 1983, numerous oil shale fragmentation tests were conducted at the Colony and Anvil Points Mines, Colorado. These experiments were part of an investigation to determine factors required for the adequate fragmentation of oil shale and to evaluate the feasibility of using the vertical modified in situ retort (VMIS) method for recovery of kerogen from oil shale. The objective of this research was to support the design of a large volume (10{sup 4} m{sup 3}) rubble bed for in situ processing. In addition, this rubble bed was to be formed in a large single-blast event which included decked charges, time delays, and multiple boreholes. Results are described.

  9. General-Purpose Heat Source development: Extended series test program large fragment tests

    SciTech Connect (OSTI)

    Cull, T.A.

    1989-08-01

    General-Purpose Heat Source radioisotope thermoelectric generators (GPHS-RTGs) will provide electric power for the NASA Galileo and European Space Agency Ulysses missions. Each GPHS-RTG comprises two major components: GPHS modules, which provide thermal energy, and a thermoelectric converter, which converts the thermal energy into electric power. Each of the 18 GPHS modules in a GPHS-RTG contains four /sup 238/PuO/sub 2/-fueled capsules. LANL conducted a series of safety verification tests on the GPHS-RTG before the scheduled May 1986 launch of the Galileo spacecraft to assess the ability of the GPHS modules to contain the plutonia in potential accident environments. As a result of the Challenger 51-L accident in January 1986, NASA postponed the launch of Galileo; the launch vehicle was reconfigured and the spacecraft trajectory was modified. These actions prompted NASA to reevaluate potential mission accidents, and an extended series safety test program was initiated. The program included a series of large fragment tests that simulated the collision of solid rocket booster (SRB) fragments, generated in an SRB motor case rupture or resulting from a range safety officer SRB destruct action, with the GPHS-RTG. The tests indicated that fueled clads, inside a converter, will not breach or release fuel after a square (142 cm on a side) SRB fragment impacts flat-on at velocities up to 212 m/s, and that only the leading fueled capsules breach and release fuel after the square SRB fragment impacts the modules, inside the converter, edge-on at 95 m/s. 8 refs., 32 figs., 7 tabs.

  10. Planetary Surface Power and Interstellar Propulsion Using Fission Fragment Magnetic Collimator Reactor

    SciTech Connect (OSTI)

    Tsvetkov, Pavel V.; Hart, Ron R.; King, Don B.; Rochau, Gary E.

    2006-01-20

    Fission energy can be used directly if the kinetic energy of fission fragments is converted to electricity and/or thrust before turning into heat. The completed US DOE NERI Direct Energy Conversion (DEC) Power Production project indicates that viable DEC systems are possible. The US DOE NERI DEC Proof of Principle project began in October of 2002 with the goal to demonstrate performance principles of DEC systems. One of the emerging DEC concepts is represented by fission fragment magnetic collimator reactors (FFMCR). Safety, simplicity, and high conversion efficiency are the unique advantages offered by these systems. In the FFMCR, the basic energy source is the kinetic energy of fission fragments. Following escape from thin fuel layers, they are captured on magnetic field lines and are directed out of the core and through magnetic collimators to produce electricity and thrust. The exiting flow of energetic fission fragments has a very high specific impulse that allows efficient planetary surface power and interstellar propulsion without carrying any conventional propellant onboard. The objective of this work was to determine technological feasibility of the concept. This objective was accomplished by producing the FFMCR design and by analysis of its performance characteristics. The paper presents the FFMCR concept, describes its development to a technologically feasible level and discusses obtained results. Performed studies offer efficiencies up to 90% and velocities approaching speed of light as potentially achievable. The unmanned 10-tons probe with 1000 MW FFMCR propulsion unit would attain mission velocity of about 2% of the speed of light. If the unit is designed for 4000 MW, then in 10 years the unmanned 10-tons probe would attain mission velocity of about 10% of the speed of light.

  11. Automatic detection of bone fragments in poultry using multi-energy x-rays

    DOE Patents [OSTI]

    Gleason, Shaun S.; Paulus, Michael J.; Mullens, James A.

    2002-04-09

    At least two linear arrays of x-ray detectors are placed below a conveyor belt in a poultry processing plant. Multiple-energy x-ray sources illuminate the poultry and are detected by the detectors. Laser profilometry is used to measure the poultry thickness as the x-ray data is acquired. The detector readout is processed in real time to detect the presence of small highly attenuating fragments in the poultry, i.e., bone, metal, and cartilage.

  12. Hanford Site Beryllium Questionnaire Affected Worker Questionnaire

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beryllium Questionnaire Affected Worker Questionnaire Page 1 of 15 Hanford Site Beryllium Interview Questionnaire Affected Worker Interview Date (MM/YYYY) Name (Last, First, MI) HID# DOB (MM/YYYY) Contractor/Employer Home Address City State Zip Code Home Phone Number ( ) - Alternate Phone Number ( ) - Hanford Site Beryllium Questionnaire Affected Worker Questionnaire Page 2 of 15 Hanford Work History Timeline Original Hire Date for the Hanford Site: (MM/YYYY) Contractor: Job Title: Bargaining

  13. A recoil ion momentum spectrometer for molecular and atomic fragmentation studies

    SciTech Connect (OSTI)

    Khan, Arnab; Tribedi, Lokesh C.; Misra, Deepankar

    2015-04-15

    We report the development and performance studies of a newly built recoil ion momentum spectrometer for the study of atomic and molecular fragmentation dynamics in gas phase upon the impact of charged particles and photons. The present design is a two-stage Wiley-McLaren type spectrometer which satisfies both time and velocity focusing conditions and is capable of measuring singly charged ionic fragments up-to 13 eV in all directions. An electrostatic lens has been introduced in order to achieve velocity imaging. Effects of the lens on time-of-flight as well as on the position have been investigated in detail, both, by simulation and in experiment. We have used 120 keV proton beam on molecular nitrogen gas target. Complete momentum distributions and kinetic energy release distributions have been derived from the measured position and time-of-flight spectra. Along with this, the kinetic energy release spectra of fragmentation of doubly ionized nitrogen molecule upon various projectile impacts are presented.

  14. Extraction of quark transversity distribution and Collins fragmentation functions with QCD evolution

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kang, Zhong-Bo; Prokudin, Alexei; Sun, Peng; Yuan, Feng

    2016-01-13

    In this paper, we study the transverse momentum dependent (TMD) evolution of the Collins azimuthal asymmetries in e+e- annihilations and semi-inclusive hadron production in deep inelastic scattering (SIDIS) processes. All the relevant coefficients are calculated up to the next-to-leading logarithmic (NLL) order accuracy. By applying the TMD evolution at the approximate NLL order in the Collins- Soper-Sterman (CSS) formalism, we extract transversity distributions for u and d quarks and Collins fragmentation functions from current experimental data by a global analysis of the Collins asymmetries in back-to-back di-hadron productions in e+e- annihilations measured by BELLE and BABAR Collaborations and SIDIS datamore » from HERMES, COMPASS, and JLab HALL A experiments. The impact of the evolution effects and the relevant theoretical uncertainties are discussed. We further discuss the TMD interpretation for our results, and illustrate the unpolarized quark distribution, transversity distribution, unpolarized quark fragmentation and Collins fragmentation functions depending on the transverse momentum and the hard momentum scale. Finally, we give predictions and discuss impact of future experiments.« less

  15. Energetics and Dynamics of Dissociation of Deprotonated Peptides: Fragmentation of Angiotensin Analogs

    SciTech Connect (OSTI)

    Laskin, Julia; Yang, Zhibo

    2011-12-01

    We present a first study of the energetics and dynamics of dissociation of deprotonated peptides using time- and collision-energy resolved surface-induced dissociation (SID) experiments. SID of four model peptides: RVYIHPF, HVYIHPF, DRVYIHPF, and DHVYIHPF was studied using a specially designed Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) configured for studying ion-surface collisions. Energy and entropy effects for the overall decomposition of the precursor ion were deduced by modeling the time- and collision energy-resolved survival curves using an RRKM based approach developed in our laboratory. The results were compared to the energetics and dynamics of dissociation of the corresponding protonated species. We demonstrate that acidic peptides are less stable in the negative mode because of the low threshold associated with the kinetically hindered loss of H2O from [M-H]- ions. Comparison between the two basic peptides indicates that the lower stability of the [M-H]- ion of RVYIHPF as compared to HVYIHPF towards fragmentation is attributed to the differences in fragmentation mechanisms. Specifically, threshold energy associated with losses of NH3 and NHCNH from RVYIHPF is lower than the barrier for backbone fragmentation that dominates gas-phase decomposition of HVYIHPF. The results provide a first quantitative comparison between the energetics and dynamics of dissociation of [M+H]+ and [M-H]- ions of acidic and basic peptides.

  16. Explosive engineering problems from fragmentation tests in oil shale at the Anvil Points Mine, Colorado

    SciTech Connect (OSTI)

    Dick, R.D.; Fourney, W.L.; Young, C.

    1985-01-01

    During 1981 and 1982, an extensive oil shale fragmentation research program was conducted at the Anvil Points Mine near Rifle, Colorado. The primary goals were to investigate factors involved for adequate fragmentation of oil shale and to evaluate the feasibility of using the modified in situ retort (MIS) method for recovery of oil from oil shale. The field test program included single-deck, single-borehole experiments to obtain basic fragmentation data; multiple-deck, multiple-borehole experiments to evaluate some practical aspects for developing an in situ retort; and the development of a variety of instrumentation technique to diagnose the blast event. This paper discusses some explosive engineering problems encountered, such as electric cap performance in complex blasting patterns, explosive and stem performance in a variety of configurations from the simple to the complex, and the difficulties experienced when reversing the direction of throw of the oil shale in a subscale retort configuration. These problems need solutions before an adequate MIS retort can be created in a single-blast event and even before an experimental mini-retort can be formed. 6 references, 7 figures, 3 tables.

  17. Dynamical interpretation of average fission-fragment kinetic energy systematics and nuclear scission

    SciTech Connect (OSTI)

    Nadtochy, P.N. [GSI, Plankstrasse 1, D-64291 Darmstadt (Germany); Omsk State University, Department of Theoretical Physics, Mira Prospect 55-A, RU-644077 Omsk (Russian Federation); Adeev, G.D. [Omsk State University, Department of Theoretical Physics, Mira Prospect 55-A, RU-644077 Omsk (Russian Federation)

    2005-11-01

    A dynamical interpretation of the well-known systematics for average total kinetic energy of fission fragments over a wide range of the Coulomb parameter (600 on the Coulomb parameter. The results of dynamical calculations of within three-dimensional Langevin dynamics show that the mean distance between the centers of mass of nascent fragments at the scission configuration increases linearly with the parameter Z{sup 2}/A{sup 1/3}. This distance changes approximately from 2.35R{sub 0} for {sup 119}Xe to 2.6R{sub 0} for {sup 256}Fm. In spite of this increase in mean distance between future fragments at scission, the linear dependence of on the parameter Z{sup 2}/A{sup 1/3} remains approximately valid over a wide range of the Coulomb parameter Z{sup 2}/A{sup 1/3}.

  18. Analysis of Transportation and Logistics Challenges Affecting...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Analysis of Transportation and Logistics Challenges Affecting the Deployment of Larger Wind Turbines: Summary of Results Analysis of Transportation and Logistics Challenges ...

  19. Analysis of Transportation and Logistics Challenges Affecting...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Figure 1. Average land-based wind turbine size and levelized cost of energy through ... breakpoints affecting U.S. land-based turbine installations ......

  20. Neutron emission effects on fragment mass and kinetic energy distribution from fission of 239{sup Pu} induced by thermal neutrons

    SciTech Connect (OSTI)

    Montoya, M.; Rojas, J.; Lobato, I.

    2010-08-04

    The average of fragment kinetic energy (E-bar sign*) and the multiplicity of prompt neutrons ({nu}(bar sign)) as a function of fragment mass (m*), as well as the fragment mass yield (Y(m*)) from thermal neutron-induced fission of {sup 239}Pu have been measured by Tsuchiya et al.. In that work the mass and kinetic energy are calculated from the measured kinetic energy of one fragment and the difference of time of flight of the two complementary fragments. However they do not present their results about the standard deviation {sigma}{sub E}*(m*). In this work we have made a numerical simulation of that experiment which reproduces its results, assuming an initial distribution of the primary fragment kinetic energy (E(A)) with a constant value of the standard deviation as function of fragment mass ({sigma}{sub E}(A)). As a result of the simulation we obtain the dependence {sigma}{sub E}*(m*) which presents an enhancement between m* = 92 and m* = 110, and a peak at m* = 121.

  1. Effects of rolling temperature and subsequent annealing on mechanical properties of ultrafine-grained Cu–Zn–Si alloy

    SciTech Connect (OSTI)

    Zhang, Xiangkai; Yang, Xuyue; Chen, Wei; Qin, Jia; Fouse, Jiaping

    2015-08-15

    The effects of rolling temperature and subsequent annealing on mechanical properties of Cu–Zn–Si alloy were investigated by using X-ray diffraction, transmission electron microscope, electron back scattered diffraction and tensile tests. The Cu–Zn–Si alloy has been processed at cryogenic temperature (approximately 77 K) and room temperature up to different rolling strains. It has been identified that the cryorolled Cu–Zn–Si alloy samples show a higher strength compared with those room temperature rolled samples. The improved strength of cryorolled samples is resulted from grain size effect and higher densities of dislocations and deformation twins. And subsequent annealing, as a post-heat treatment, enhanced the ductility. An obvious increase in uniform elongation appears when the volume fraction of static recrystallization grains exceeds 25%. The strength–ductility combination of the annealed cryorolled samples is superior to that of annealed room temperature rolled samples, owing to the finer grains, high fractions of high angle grain boundaries and twins. - Highlights: • An increase in hardness of Cu–Zn–Si alloy is noticed during annealing process. • Thermal stability is reduced in Cu–Zn–Si alloy by cryorolling. • An obvious enhancement in UE is noticed when fraction of SRX grains exceeds 25%. • A superior strength–ductility combination is achieved in the cryorolling samples.

  2. Calculated fission-fragment yield systematics in the region 74 <=Z <= 94 and 90 <=N <= 150

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Möller, Peter; Randrup, Jørgen

    2015-04-01

    Background: In the seminal experiment by Schmidt et al. [Nucl. Phys. A 665, 221 (2000)] in which fission-fragment charge distributions were obtained for 70 nuclides, asymmetric distributions were seen above nucleon number A ≈ 226 and symmetric ones below. Because asymmetric fission had often loosely been explained as a preference for the nucleus to always exploit the extra binding of fragments near ¹³²Sn it was assumed that all systems below A ≈ 226 would fission symmetrically because available isotopes do not have a proton-to-neutron Z/N ratio that allows division into fragments near ¹³²Sn. But the finding by Andreyev et al.more » [Phys. Rev. Lett. 105, 252502 (2010)] did not conform to this expectation because the compound system ¹⁸⁰Hg was shown to fission asymmetrically. It was suggested that this was a new type of asymmetric fission, because no strong shell effects occur for any possible fragment division. Purpose: We calculate a reference database for fission-fragment mass yields for a large region of the nuclear chart comprising 987 nuclides. A particular aim is to establish whether ¹⁸⁰Hg is part of a contiguous region of asymmetric fission, and if so, its extent, or if not, in contrast to the actinides, there are scattered smaller groups of nuclei that fission asymmetrically in this area of the nuclear chart. Methods: We use the by now well benchmarked Brownian shape-motion method and perform random walks on the previously calculated five-dimensional potential-energy surfaces. The calculated shell corrections are damped out with energy according to a prescription developed earlier. Results: We have obtained a theoretical reference database of fission-fragment mass yields for 987 nuclides. These results show an extended region of asymmetric fission with approximate extension 74 ≤ Z ≤ 85 and 100 ≤ N ≤ 120. The calculated yields are highly variable. We show 20 representative plots of these variable features and summarize the main

  3. Calculated fission-fragment yield systematics in the region 74 <=Z <= 94 and 90 <=N <= 150

    SciTech Connect (OSTI)

    Möller, Peter; Randrup, Jørgen

    2015-04-01

    Background: In the seminal experiment by Schmidt et al. [Nucl. Phys. A 665, 221 (2000)] in which fission-fragment charge distributions were obtained for 70 nuclides, asymmetric distributions were seen above nucleon number A ≈ 226 and symmetric ones below. Because asymmetric fission had often loosely been explained as a preference for the nucleus to always exploit the extra binding of fragments near ¹³²Sn it was assumed that all systems below A ≈ 226 would fission symmetrically because available isotopes do not have a proton-to-neutron Z/N ratio that allows division into fragments near ¹³²Sn. But the finding by Andreyev et al. [Phys. Rev. Lett. 105, 252502 (2010)] did not conform to this expectation because the compound system ¹⁸⁰Hg was shown to fission asymmetrically. It was suggested that this was a new type of asymmetric fission, because no strong shell effects occur for any possible fragment division. Purpose: We calculate a reference database for fission-fragment mass yields for a large region of the nuclear chart comprising 987 nuclides. A particular aim is to establish whether ¹⁸⁰Hg is part of a contiguous region of asymmetric fission, and if so, its extent, or if not, in contrast to the actinides, there are scattered smaller groups of nuclei that fission asymmetrically in this area of the nuclear chart. Methods: We use the by now well benchmarked Brownian shape-motion method and perform random walks on the previously calculated five-dimensional potential-energy surfaces. The calculated shell corrections are damped out with energy according to a prescription developed earlier. Results: We have obtained a theoretical reference database of fission-fragment mass yields for 987 nuclides. These results show an extended region of asymmetric fission with approximate extension 74 ≤ Z ≤ 85 and 100 ≤ N ≤ 120. The calculated yields are highly variable. We show 20 representative plots of these variable features and summarize the

  4. Calculated fission-fragment yield systematics in the region 74 <=Z <= 94 and 90 <=N <= 150

    SciTech Connect (OSTI)

    Mller, Peter; Randrup, Jrgen

    2015-04-01

    Background: In the seminal experiment by Schmidt et al. [Nucl. Phys. A 665, 221 (2000)] in which fission-fragment charge distributions were obtained for 70 nuclides, asymmetric distributions were seen above nucleon number A ? 226 and symmetric ones below. Because asymmetric fission had often loosely been explained as a preference for the nucleus to always exploit the extra binding of fragments near Sn it was assumed that all systems below A ? 226 would fission symmetrically because available isotopes do not have a proton-to-neutron Z/N ratio that allows division into fragments near Sn. But the finding by Andreyev et al. [Phys. Rev. Lett. 105, 252502 (2010)] did not conform to this expectation because the compound system ??Hg was shown to fission asymmetrically. It was suggested that this was a new type of asymmetric fission, because no strong shell effects occur for any possible fragment division. Purpose: We calculate a reference database for fission-fragment mass yields for a large region of the nuclear chart comprising 987 nuclides. A particular aim is to establish whether ??Hg is part of a contiguous region of asymmetric fission, and if so, its extent, or if not, in contrast to the actinides, there are scattered smaller groups of nuclei that fission asymmetrically in this area of the nuclear chart. Methods: We use the by now well benchmarked Brownian shape-motion method and perform random walks on the previously calculated five-dimensional potential-energy surfaces. The calculated shell corrections are damped out with energy according to a prescription developed earlier. Results: We have obtained a theoretical reference database of fission-fragment mass yields for 987 nuclides. These results show an extended region of asymmetric fission with approximate extension 74 ? Z ? 85 and 100 ? N ? 120. The calculated yields are highly variable. We show 20 representative plots of these variable features and summarize the main aspects of our results

  5. Fragmentation functions at next-to-next-to-leading order accuracy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Anderle, Daniele P.; Stratmann, Marco; Ringer, Felix

    2015-12-14

    We present a first analysis of parton-to-pion fragmentation functions at next-to-next-to-leading order accuracy in QCD based on single-inclusive pion production in electron-positron annihilation. Special emphasis is put on the technical details necessary to perform the QCD scale evolution and cross section calculation in Mellin moment space. Lastly, we demonstrate how the description of the data and the theoretical uncertainties are improved when next-to-next-to-leading order QCD corrections are included.

  6. Extraction of pion non-perturbative fragmentation functions in ZM-VFNS

    SciTech Connect (OSTI)

    Soleymaninia, M.; Khorramian, A. N.; Moosavinejad, S. M.

    2012-10-23

    We present pion non-perturbative fragmentation functions (non-pFFs) at next-to-leading order (NLO) obtained through a global fit to electron-positron annihilation data from CERN LEP1, SLAC SLC, DESY and KEK, using zero-mass variable-flavor-number scheme. We apply the obtained non-pFFs to predict the scaled-energy distribution of {pi}{sup {+-}} inclusively produced in top-quark decays. The results are in good agreement with the available theoretical models.

  7. AutoDrug: fully automated macromolecular crystallography workflows for fragment-based drug discovery

    SciTech Connect (OSTI)

    Tsai, Yingssu; McPhillips, Scott E.; Gonzlez, Ana; McPhillips, Timothy M.; Zinn, Daniel; Cohen, Aina E.; Feese, Michael D.; Bushnell, David; Tiefenbrunn, Theresa; Stout, C. David; Ludaescher, Bertram; Hedman, Britt; Hodgson, Keith O.; Soltis, S. Michael

    2013-05-01

    New software has been developed for automating the experimental and data-processing stages of fragment-based drug discovery at a macromolecular crystallography beamline. A new workflow-automation framework orchestrates beamline-control and data-analysis software while organizing results from multiple samples. AutoDrug is software based upon the scientific workflow paradigm that integrates the Stanford Synchrotron Radiation Lightsource macromolecular crystallography beamlines and third-party processing software to automate the crystallography steps of the fragment-based drug-discovery process. AutoDrug screens a cassette of fragment-soaked crystals, selects crystals for data collection based on screening results and user-specified criteria and determines optimal data-collection strategies. It then collects and processes diffraction data, performs molecular replacement using provided models and detects electron density that is likely to arise from bound fragments. All processes are fully automated, i.e. are performed without user interaction or supervision. Samples can be screened in groups corresponding to particular proteins, crystal forms and/or soaking conditions. A single AutoDrug run is only limited by the capacity of the sample-storage dewar at the beamline: currently 288 samples. AutoDrug was developed in conjunction with RestFlow, a new scientific workflow-automation framework. RestFlow simplifies the design of AutoDrug by managing the flow of data and the organization of results and by orchestrating the execution of computational pipeline steps. It also simplifies the execution and interaction of third-party programs and the beamline-control system. Modeling AutoDrug as a scientific workflow enables multiple variants that meet the requirements of different user groups to be developed and supported. A workflow tailored to mimic the crystallography stages comprising the drug-discovery pipeline of CoCrystal Discovery Inc. has been deployed and successfully

  8. Half-life measurements of isomeric states populated in projectile fragmentation

    SciTech Connect (OSTI)

    Bowry, M.; Podolay, Zs.

    2012-10-20

    The half-lives of excited isomeric states observed in {sup 195}Au, {sup 201}Tl and {sup 215}Rn are reported for the first time. Delayed {gamma}-rays were correlated with nuclei produced in the projectile fragmentation of relativistic {sup 238}U ions, unambiguously identified in terms of their atomic number (Z) and mass-to-charge ratio (A/Q) after traversing an in-flight separator. The observation of a long-lived isomeric state in {sup 195}Au with t{sub 1/2} = 16{sub -4}{sup +8}{mu}s is presented. Two shorter-lived isomeric states were detected in {sup 201}Tl and {sup 215}Rn with t{sub 1/2} = 95{sub -21}{sup +39} and 57{sub -12}{sup +21} ns respectively. In total 24 isomeric states were identified in different nuclei from Pt to Rn (A {approx} 200) during the current study, the majority of which were previously reported. The wealth of spectroscopic data provides the opportunity to determine the isomeric ratios over a wide range of Z, A and angular momentum (I h) of the reaction products. In particular, high-spin states with I Greater-Than-Or-Equivalent-To 18 h provide a robust test of theoretical models of fragmentation.

  9. MCNP6 Simulation of Light and Medium Nuclei Fragmentation at Intermediate Energies

    SciTech Connect (OSTI)

    Mashnik, Stepan Georgievich; Kerby, Leslie Marie

    2015-05-22

    MCNP6, the latest and most advanced LANL Monte Carlo transport code, representing a merger of MCNP5 and MCNPX, is actually much more than the sum of those two computer codes; MCNP6 is available to the public via RSICC at Oak Ridge, TN, USA. In the present work, MCNP6 was validated and verified (V&V) against different experimental data on intermediate-energy fragmentation reactions, and results by several other codes, using mainly the latest modifications of the Cascade-Exciton Model (CEM) and of the Los Alamos version of the Quark-Gluon String Model (LAQGSM) event generators CEM03.03 and LAQGSM03.03. It was found that MCNP6 using CEM03.03 and LAQGSM03.03 describes well fragmentation reactions induced on light and medium target nuclei by protons and light nuclei of energies around 1 GeV/nucleon and below, and can serve as a reliable simulation tool for different applications, like cosmic-ray-induced single event upsets (SEU’s), radiation protection, and cancer therapy with proton and ion beams, to name just a few. Future improvements of the predicting capabilities of MCNP6 for such reactions are possible, and are discussed in this work.

  10. Oxidation Unzipping of Stable Nanographenes into Joint Spin-rich Fragments

    SciTech Connect (OSTI)

    Jiang, Deen; Wang, Lu; Gao, Xingfa; Ohtsuka, Yuhki; Zhao, Yuliang; Nagase, Shigeru

    2009-01-01

    When an all-benzenoid nanographene is linearly unzipped into oxygen-joined fragments, the oxidized benzenoid rings (aromatic sextets) selectively adopt the low-spin (DeltaS = 0) or high-spin conformation (DeltaS = 1) to yield the thermally most stable isomer. The selection of the conformation depends simply on the position of the aromatic sextets: the inner ones prefer the high-spin conformation, whereas the peripheral ones prefer the low-spin conformation. Therefore, the resulting most stable isomer has a total spin whose value equals the number of inner aromatic sextets (n(i)) along the oxidizing line. The nanographene fragments contained in this isomer have a ferromagnetic spin coupling. Due to the tautomerization between the high-spin and low-spin conformations, there also exist other possible isomers with higher energies and with spins at ground state ranging from 0 to (n(i) - 1). The rich geometrically correlated spins and the adjustable energy gaps indicate great potential of the graphene oxides in spintronic devices.

  11. Fragment approach to constrained density functional theory calculations using Daubechies wavelets

    SciTech Connect (OSTI)

    Ratcliff, Laura E.; Genovese, Luigi; Mohr, Stephan; Deutsch, Thierry

    2015-06-21

    In a recent paper, we presented a linear scaling Kohn-Sham density functional theory (DFT) code based on Daubechies wavelets, where a minimal set of localized support functions are optimized in situ and therefore adapted to the chemical properties of the molecular system. Thanks to the systematically controllable accuracy of the underlying basis set, this approach is able to provide an optimal contracted basis for a given system: accuracies for ground state energies and atomic forces are of the same quality as an uncontracted, cubic scaling approach. This basis set offers, by construction, a natural subset where the density matrix of the system can be projected. In this paper, we demonstrate the flexibility of this minimal basis formalism in providing a basis set that can be reused as-is, i.e., without reoptimization, for charge-constrained DFT calculations within a fragment approach. Support functions, represented in the underlying wavelet grid, of the template fragments are roto-translated with high numerical precision to the required positions and used as projectors for the charge weight function. We demonstrate the interest of this approach to express highly precise and efficient calculations for preparing diabatic states and for the computational setup of systems in complex environments.

  12. Preliminary X-ray crystallographic studies of mouse UPR responsive protein P58(IPK) TPR fragment

    SciTech Connect (OSTI)

    Tao, Jiahui; Wu, Yunkun [Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Ron, David [Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016 (United States); Sha, Bingdong, E-mail: bdsha@uab.edu [Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35294 (United States)

    2008-02-01

    To investigate the mechanism by which P58(IPK) functions to promote protein folding within the ER, a P58(IPK) TPR fragment without the C-terminal J-domain has been crystallized. Endoplasmic reticulum (ER) stress induces the unfolded protein response (UPR), which can promote protein folding and misfolded protein degradation and attenuate protein translation and protein translocation into the ER. P58(IPK) has been proposed to function as a molecular chaperone to maintain protein-folding homeostasis in the ER under normal and stressed conditions. P58(IPK) contains nine TPR motifs and a C-terminal J-domain within its primary sequence. To investigate the mechanism by which P58(IPK) functions to promote protein folding within the ER, a P58(IPK) TPR fragment without the C-terminal J-domain was crystallized. The crystals diffract to 2.5 resolution using a synchrotron X-ray source. The crystals belong to space group P2{sub 1}, with unit-cell parameters a = 83.53, b = 92.75, c = 84.32 , ? = 90.00, ? = 119.36, ? = 90.00. There are two P58(IPK) molecules in the asymmetric unit, which corresponds to a solvent content of approximately 60%. Structure determination by MAD methods is under way.

  13. Evolution of heavy metals in municipal solid waste during bio-drying and implications of their subsequent transfer during combustion

    SciTech Connect (OSTI)

    Zhang Dongqing; Zhang Hua; Wu Changlin; Shao Liming; He Pinjing

    2011-08-15

    Bio-drying has been applied to improve the heating value of municipal solid waste (MSW) prior to combustion. In the present study, evolution of heavy metals in MSW during bio-drying and subsequent combustion was studied using one aerobic and two combined hydrolytic-aerobic scenarios. Heavy metals were concentrated during bio-drying and transformed between different metal fractions, namely the exchangeable, carbonate-bound, iron- and manganese-oxides-bound, organic-matter-bound and residual fractions. The amounts of heavy metals per kg of bio-dried MSW transferred into combustion flue gas increased with bio-drying time, primarily due to metals enrichment from organics degradation. Because of their volatility, the partitioning ratios of As and Hg in flue gas remained stable so that bio-drying and heavy metal speciation had little effect on their transfer and partitioning during combustion. In contrast, the partitioning ratios of Pb, Zn and Cu tended to increase after bio-drying, which likely enhanced their release potential during combustion.

  14. High-resolution (e, 2e + ion) study of electron-impact ionization and fragmentation of methane

    SciTech Connect (OSTI)

    Ren, Xueguang Pflger, Thomas; Weyland, Marvin; Baek, Woon Yong; Rabus, Hans; Ullrich, Joachim; Dorn, Alexander

    2015-05-07

    The ionization and fragmentation of methane induced by low-energy (E{sub 0} = 66 eV) electron-impact is investigated using a reaction microscope. The momentum vectors of all three charged final state particles, two outgoing electrons, and one fragment ion, are detected in coincidence. Compared to the earlier study [Xu et al., J. Chem. Phys. 138, 134307 (2013)], considerable improvements to the instrumental mass and energy resolutions have been achieved. The fragment products CH{sub 4}{sup +}, CH{sub 3}{sup +}, CH{sub 2}{sup +}, CH{sup +}, and C{sup +} are clearly resolved. The binding energy resolution of ?E = 2.0 eV is a factor of three better than in the earlier measurements. The fragmentation channels are investigated by measuring the ion kinetic energy distributions and the binding energy spectra. While being mostly in consistence with existing photoionization studies the results show differences including missing fragmentation channels and previously unseen channels.

  15. Fragment-based {sup 13}C nuclear magnetic resonance chemical shift predictions in molecular crystals: An alternative to planewave methods

    SciTech Connect (OSTI)

    Hartman, Joshua D.; Beran, Gregory J. O.; Monaco, Stephen; Schatschneider, Bohdan

    2015-09-14

    We assess the quality of fragment-based ab initio isotropic {sup 13}C chemical shift predictions for a collection of 25 molecular crystals with eight different density functionals. We explore the relative performance of cluster, two-body fragment, combined cluster/fragment, and the planewave gauge-including projector augmented wave (GIPAW) models relative to experiment. When electrostatic embedding is employed to capture many-body polarization effects, the simple and computationally inexpensive two-body fragment model predicts both isotropic {sup 13}C chemical shifts and the chemical shielding tensors as well as both cluster models and the GIPAW approach. Unlike the GIPAW approach, hybrid density functionals can be used readily in a fragment model, and all four hybrid functionals tested here (PBE0, B3LYP, B3PW91, and B97-2) predict chemical shifts in noticeably better agreement with experiment than the four generalized gradient approximation (GGA) functionals considered (PBE, OPBE, BLYP, and BP86). A set of recommended linear regression parameters for mapping between calculated chemical shieldings and observed chemical shifts are provided based on these benchmark calculations. Statistical cross-validation procedures are used to demonstrate the robustness of these fits.

  16. Environmental issues affecting clean coal technology deployment

    SciTech Connect (OSTI)

    Miller, M.J.

    1997-12-31

    The author outlines what he considers to be the key environmental issues affecting Clean Coal Technology (CCT) deployment both in the US and internationally. Since the international issues are difficult to characterize given different environmental drivers in various countries and regions, the primary focus of his remarks is on US deployment. However, he makes some general remarks, particularly regarding the environmental issues in developing vs. developed countries and how these issues may affect CCT deployment. Further, how environment affects deployment depends on which particular type of clean coal technology one is addressing. It is not the author`s intention to mention many specific technologies other than to use them for the purposes of example. He generally categorizes CCTs into four groups since environment is likely to affect deployment for each category somewhat differently. These four categories are: Precombustion technologies such as coal cleaning; Combustion technologies such as low NOx burners; Postcombustion technologies such as FGD systems and postcombustion NOx control; and New generation technologies such as gasification and fluidized bed combustion.

  17. Factors Affecting PMU Installation Costs (October 2014)

    Broader source: Energy.gov [DOE]

    The Department of Energy investigated the major cost factors that affected PMU installation costs for the synchrophasor projects funded through the Recovery Act Smart Grid Programs. The data was compiled through interviews with the nine projects that deployed production grade synchrophasor systems.

  18. Modeling theta-theta Interactions with the Effective Fragment Potential Method: The Benzene Dimer and Substituents

    SciTech Connect (OSTI)

    Toni Smithl; Lyudmila V. Slipchenko; Mark S. Gordon

    2008-02-27

    This study compares the results of the general effective fragment potential (EFP2) method to the results of a previous combined coupled cluster with single, double, and perturbative triple excitations [CCSD(T)] and symmetry-adapted perturbation theory (SAPT) study [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690] on substituent effects in {pi}-{pi} interactions. EFP2 is found to accurately model the binding energies of the benzene-benzene, benzene-phenol, benzene-toluene, benzene-fluorobenzene, and benzene-benzonitrile dimers, as compared with high-level methods [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690], but at a fraction of the computational cost of CCSD(T). In addition, an EFP-based Monte Carlo/simulated annealing study was undertaken to examine the potential energy surface of the substituted dimers.

  19. Unpolarised transverse momentum dependent distribution and fragmentation functions from SIDIS multiplicities

    SciTech Connect (OSTI)

    Anselmino, M.; Boglione, M.; H. J.O. Gonzalez; Melis, S.; Prokudin, A.

    2014-04-01

    In this study, the unpolarised transverse momentum dependent distribution and fragmentation functions are extracted from HERMES and COMPASS experimental measurements of SIDIS multiplicities for charged hadron production. The data are grouped into independent bins of the kinematical variables, in which the TMD factorisation is expected to hold. A simple factorised functional form of the TMDs is adopted, with a Gaussian dependence on the intrinsic transverse momentum, which turns out to be quite adequate in shape. HERMES data do not need any normalisation correction, while fits of the COMPASS data much improve with a y-dependent overall normalisation factor. A comparison of the extracted TMDs with previous EMC and JLab data confirms the adequacy of the simple gaussian distributions. The possible role of the TMD evolution is briefly considered.

  20. Unpolarised transverse momentum dependent distribution and fragmentation functions from SIDIS multiplicities

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Anselmino, M.; Boglione, M.; H. J.O. Gonzalez; Melis, S.; Prokudin, A.

    2014-04-01

    In this study, the unpolarised transverse momentum dependent distribution and fragmentation functions are extracted from HERMES and COMPASS experimental measurements of SIDIS multiplicities for charged hadron production. The data are grouped into independent bins of the kinematical variables, in which the TMD factorisation is expected to hold. A simple factorised functional form of the TMDs is adopted, with a Gaussian dependence on the intrinsic transverse momentum, which turns out to be quite adequate in shape. HERMES data do not need any normalisation correction, while fits of the COMPASS data much improve with a y-dependent overall normalisation factor. A comparison ofmore » the extracted TMDs with previous EMC and JLab data confirms the adequacy of the simple gaussian distributions. The possible role of the TMD evolution is briefly considered.« less

  1. Assessing deforestation and habitat fragmentation in Uganda using satellite observations and fractal analysis

    SciTech Connect (OSTI)

    Hlavka, C.A.; Strong, L.L. )

    1992-10-01

    The MSS, SPOT, and AVHRR imagery of Ugandan forests were analyzed to assess the information content related to deforestation and tropical habitat fragmentation, focusing primarily on the Kibale and Mabira Forests. Analysis of actual and simulated AVHRR imagery showed that it might be possible to monitor major changes in forest extent with the relatively coarse spatial resolution of AVHRR imagery (about 1 km) provided ancillary data were available. The fractal dimension of the forest edges, measured with the Landsat and SPOT imagery, was consistently about 1.7 or 1.8. This high fractal dimension was due to the coplex pattern of clearings, remnant forest stands, and jagged forest edges caused by repeated human encroachment over centuries. 28 refs.

  2. Structure of the N-terminal fragment of Escherichia coli Lon protease

    SciTech Connect (OSTI)

    Li, Mi; Gustchina, Alla; Rasulova, Fatima S.; Melnikov, Edward E.; Maurizi, Michael R.; Rotanova, Tatyana V.; Dauter, Zbigniew; Wlodawer, Alexander

    2010-08-01

    The medium-resolution structure of the N-terminal fragment of E. coli Lon protease shows that this part of the enzyme consists of two compact domains and a very long α-helix. The structure of a recombinant construct consisting of residues 1–245 of Escherichia coli Lon protease, the prototypical member of the A-type Lon family, is reported. This construct encompasses all or most of the N-terminal domain of the enzyme. The structure was solved by SeMet SAD to 2.6 Å resolution utilizing trigonal crystals that contained one molecule in the asymmetric unit. The molecule consists of two compact subdomains and a very long C-terminal α-helix. The structure of the first subdomain (residues 1–117), which consists mostly of β-strands, is similar to that of the shorter fragment previously expressed and crystallized, whereas the second subdomain is almost entirely helical. The fold and spatial relationship of the two subdomains, with the exception of the C-terminal helix, closely resemble the structure of BPP1347, a 203-amino-acid protein of unknown function from Bordetella parapertussis, and more distantly several other proteins. It was not possible to refine the structure to satisfactory convergence; however, since almost all of the Se atoms could be located on the basis of their anomalous scattering the correctness of the overall structure is not in question. The structure reported here was also compared with the structures of the putative substrate-binding domains of several proteins, showing topological similarities that should help in defining the binding sites used by Lon substrates.

  3. General-purpose heat source: Research and development program, radioisotope thermoelectric generator/thin fragment impact test

    SciTech Connect (OSTI)

    Reimus, M.A.H.; Hinckley, J.E.

    1996-11-01

    The general-purpose heat source provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system. The results of this test indicated that impact by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel.

  4. Prediction of the energy dependence of molecular fragmentation cross sections for collisions of swift protons with ethane and acetylene

    SciTech Connect (OSTI)

    Cabrera-Trujillo, Remigio; Sabin, John R.; Deumens, Erik; Oehrn, Yngve

    2005-04-01

    We report the energy-dependent fragmentation cross sections for several of the more likely fragmentation channels for protons with up to 10 keV impact energy colliding with acetylene and ethane. We find that the predominant channels are those which involve the dissociation of a carbon-hydrogen bond, and we find that the cross sections for these channels are maximum in the low-projectile-energy region. The cross sections for fragmentation involving dissociation of a C-C bond are an order of magnitude smaller and peak at somewhat higher projectile energy. Although there are no experimental values with which to compare, it appears that selection of projectile energy can be used to influence branching ratios in proton-hydrocarbon collisions and, by implication, in other ion-molecule and atom-molecule collisions.

  5. Small-angle fragmentation of carbon ions at 0.6 GeV/n. A comparison with models of ion-ion interactions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Krutenkova, Anna P.; Abramov, B. M.; Alekseev, P. N.; Borodin, Yu. A.; Bulychjov, S. A.; Dukhovskoy, I. A.; Khanov, A. I.; Kulikov, V. V.; Martemianov, M. A.; Mashnik, Stepan Georgievich; et al

    2015-05-29

    The momentum distributions of hydrogen and helium isotopes from 12C fragmentation at 3.5° were measured at 0.6 GeV/nucleon in the FRAGM experiment at ITEP TWA heavy ion accelerator. The fragments were selected by correlated time of flight and dE/dx measurements with a magnetic spectrometer with scintillation counters. The main attention was drawn to the high momentum region where the fragment velocity exceeds the velocity of the projectile nucleus. The momentum spectra of fragments span the region of the fragmentation peak as well as the cumulative region. Moreover, the differential cross sections cover six orders of magnitude. The distributions measured aremore » compared to the predictions of three ion-ion interaction models: BC, QMD and LAQGSM03.03. The kinetic energy spectra of fragments in the projectile rest frame have an exponential shape with two temperatures, being defined by their slope parameters.« less

  6. Small-angle fragmentation of carbon ions at 0.6 GeV/n: A comparison with models of ion-ion interactions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Krutenkova, A. P.; Abramov, B. M.; Alekseev, P. N.; Borodin, Yu. A.; Bulychjov, S. A.; Dukhovskoy, I. A.; Khanov, A. I.; Kulikov, V. V.; Martemianov, M. A.; Mashnik, S. G.; et al

    2015-05-29

    Momentum distributions of hydrogen and helium isotopes from ¹²C fragmentation at 3.5° were measured at 0.6 GeV/nucleon in the FRAGM experiment at ITEP TWA heavy ion accelerator. The fragments were selected by correlated time of flight and dE/dx measurements with a magnetic spectrometer with scintillation counters. The main attention was drawn to the high momentum region where the fragment velocity exceeds the velocity of the projectile nucleus. The momentum spectra of fragments span the region of the fragmentation peak as well as the cumulative region. The differential cross sections cover six orders of magnitude. The distributions measured are compared tomore » the predictions of three ion-ion interaction models: BC, QMD and LAQGSM03.03. The kinetic energy spectra of fragments in the projectile rest frame have an exponential shape with two temperatures, being defined by their slope parameters.« less

  7. Small-angle fragmentation of carbon ions at 0.6 GeV/n: A comparison with models of ion-ion interactions

    SciTech Connect (OSTI)

    Krutenkova, A. P.; Abramov, B. M.; Alekseev, P. N.; Borodin, Yu. A.; Bulychjov, S. A.; Dukhovskoy, I. A.; Khanov, A. I.; Kulikov, V. V.; Martemianov, M. A.; Mashnik, S. G.; Matsyuk, M. A.; Turdakina, E. N.; Bravina, L.; Foka, Y.; Kabana, S.

    2015-05-29

    Momentum distributions of hydrogen and helium isotopes from C fragmentation at 3.5 were measured at 0.6 GeV/nucleon in the FRAGM experiment at ITEP TWA heavy ion accelerator. The fragments were selected by correlated time of flight and dE/dx measurements with a magnetic spectrometer with scintillation counters. The main attention was drawn to the high momentum region where the fragment velocity exceeds the velocity of the projectile nucleus. The momentum spectra of fragments span the region of the fragmentation peak as well as the cumulative region. The differential cross sections cover six orders of magnitude. The distributions measured are compared to the predictions of three ion-ion interaction models: BC, QMD and LAQGSM03.03. The kinetic energy spectra of fragments in the projectile rest frame have an exponential shape with two temperatures, being defined by their slope parameters.

  8. Endocrine disrupting chemicals affect the adipogenic differentiation of mesenchymal stem cells in distinct ontogenetic windows

    SciTech Connect (OSTI)

    Biemann, Ronald; Navarrete Santos, Anne; Navarrete Santos, Alexander; Riemann, Dagmar; Knelangen, Julia; Blueher, Matthias; Koch, Holger; Fischer, Bernd

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer Endocrine disrupting chemicals affect adipogenesis in mesenchymal stem cells (MSC). Black-Right-Pointing-Pointer The adipogenic impact depends strongly on the window of exposure. Black-Right-Pointing-Pointer Bisphenol A reduces the potential of MSC to differentiate into adipocytes. Black-Right-Pointing-Pointer DEHP and TBT trigger the adipogenic differentiation of mesenchymal stem cells. Black-Right-Pointing-Pointer BPA, DEHP and TBT did not affect adipogenesis in embryonic stem cells. -- Abstract: Endocrine disrupting chemicals (EDC) like bisphenol A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and tributyltin (TBT) are ubiquitously present in the environment and in human tissues. They bind to nuclear hormone receptors and affect cellular and developmental processes. In this study, we show that BPA, DEHP and TBT affect the adipogenic differentiation of murine mesenchymal stem cells (MSC, C3H/10T1/2) in a concentration-, stage- and compound-specific manner. C3H/10T1/2 cells and embryonic stem cells (CGR8) were exposed to BPA, DEHP or TBT at different stages of cell determination and differentiation (undifferentiated growth, adipogenic induction and terminal adipogenic differentiation). The final amount of differentiated adipocytes, cellular triglyceride content and mRNA expression of adipogenic marker genes (adiponectin, FABP4, PPAR{gamma}2, LPL) were quantified and compared with corresponding unexposed cells. BPA (10 {mu}M) decreased subsequent adipogenic differentiation of MSC, when cells were exposed during undifferentiated growth. In contrast, DEHP (100 {mu}M) during the hormonal induction period, and TBT (100 nM) in all investigated stages, enhanced adipogenesis. Importantly, exposure of undifferentiated murine embryonic stem cells did not show any effect of the investigated EDC on subsequent adipogenic differentiation.

  9. Unpolarised TMD Distribution and Fragmentation Functions from recent HERMES and COMPASS Semi-inclusive Deep Inelastic Scattering Multiplicities

    SciTech Connect (OSTI)

    Prokudin, Alexey; Anselmino, Mauro; Boglione, Mariaelena; Melis, Stefano; Gonzalez, J. O.

    2014-10-01

    The unpolarised transverse momentum dependent distribution and fragmentation functions (TMDs) are extracted from HERMES and COMPASS experimental measurements of semi- inclusive deep inelastic scattering multiplicities for charged hadron production. A simple factorised functional form of the TMDs is adopted, with a Gaussian dependence on the intrinsic transverse momentum, which turns out to be quite adequate in shape.

  10. Predicting the Velocity and Azimuth of Fragments Generated by the Range Destruction or Random Failure of Rocket Casings and Tankage

    SciTech Connect (OSTI)

    Eck, Marshall B.; Mukunda, Meera

    1988-10-01

    The details of a predictive analytical modeling process as well as the development of normalized relations for momentum partition as a function of SRM burn time and initial geometry are discussed in this paper. Methods for applying similar modeling techniques to liquid-tankage-over-pressure failures are also discussed. These methods have been calibrated against observed SRM ascent failures and on-orbit tankage failures. Casing-quadrant sized fragments with velocities exceeding 100 m/s resulted from Titan 34D-SRM range destruct actions at 10 sec mission elapsed time (MET). Casing-quadrant sized fragments with velocities of approximately 200 m/s resulted from STS-SRM range destruct actions at 110 sec MET. Similar sized fragments for Ariane third stage and Delta second stage tankage were predicted to have maximum velocities of 260 m/s and 480 m/s respectively. Good agreement was found between the predictions and observations for five specific events and it was concluded that the methods developed have good potential for use in predicting the fragmentation process of a number of generically similar casing and tankage systems. There are three copies in the file, one of these is loose.

  11. Fission fragment charge and mass distributions in 239Pu(n, f ) in the adiabatic nuclear energy density functional theory

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Regnier, D.; Dubray, N.; Schunck, N.; Verriere, M.

    2016-05-13

    Here, accurate knowledge of fission fragment yields is an essential ingredient of numerous applications ranging from the formation of elements in the r process to fuel cycle optimization for nuclear energy. The need for a predictive theory applicable where no data are available, together with the variety of potential applications, is an incentive to develop a fully microscopic approach to fission dynamics.

  12. Recombination enhances HIV-1 envelope diversity by facilitating the survival of latent genomic fragments in the plasma virus population

    SciTech Connect (OSTI)

    Immonen, Taina T.; Conway, Jessica M.; Romero-Severson, Ethan O.; Perelson, Alan S.; Leitner, Thomas; Kouyos, Roger Dimitri

    2015-12-22

    HIV-1 is subject to immune pressure exerted by the host, giving variants that escape the immune response an advantage. Virus released from activated latent cells competes against variants that have continually evolved and adapted to host immune pressure. Nevertheless, there is increasing evidence that virus displaying a signal of latency survives in patient plasma despite having reduced fitness due to long-term immune memory. We investigated the survival of virus with latent envelope genomic fragments by simulating within-host HIV-1 sequence evolution and the cycling of viral lineages in and out of the latent reservoir. Our model incorporates a detailed mutation process including nucleotide substitution, recombination, latent reservoir dynamics, diversifying selection pressure driven by the immune response, and purifying selection pressure asserted by deleterious mutations. We evaluated the ability of our model to capture sequence evolution in vivo by comparing our simulated sequences to HIV-1 envelope sequence data from 16 HIV-infected untreated patients. Empirical sequence divergence and diversity measures were qualitatively and quantitatively similar to those of our simulated HIV-1 populations, suggesting that our model invokes realistic trends of HIV-1 genetic evolution. Moreover, reconstructed phylogenies of simulated and patient HIV-1 populations showed similar topological structures. Our simulation results suggest that recombination is a key mechanism facilitating the persistence of virus with latent envelope genomic fragments in the productively infected cell population. Recombination increased the survival probability of latent virus forms approximately 13-fold. Prevalence of virus with latent fragments in productively infected cells was observed in only 2% of simulations when we ignored recombination, while the proportion increased to 27% of simulations when we allowed recombination. We also found that the selection pressures exerted by different fitness

  13. Exporting licensing regulations affecting US geothermal firms

    SciTech Connect (OSTI)

    Not Available

    1988-08-01

    This document presents a brief introduction and overview of the Department of Commerce's Export Administration Regulations which might affect potential US geothermal goods exporters. It is intended to make US geothermal firms officials aware of the existence of such regulations and to provide them with references, contacts and phone numbers where they can obtain specific and detailed information and assistance. It must be stressed however, that the ultimate responsibility for complying with the above mentioned regulations lies with the exporter who must consult the complete version of the regulations.

  14. Kenya-Affecting Electricity Policy through a Community Micro...

    Open Energy Info (EERE)

    Affecting Electricity Policy through a Community Micro Hydro Project Jump to: navigation, search Name Kenya-Affecting Electricity Policy through a Community Micro Hydro Project...

  15. Financial Incentives Available for Facilities Affected by the...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Financial Incentives Available for Facilities Affected by the US EPA Boiler MACT Proposed Rule, December 2012 Financial Incentives Available for Facilities Affected by the US EPA ...

  16. Key Parameters Affecting DPF Performance Degradation and Impact...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy Key Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy ...

  17. Study of Factors Affecting Shrub Establishment on the Monticello...

    Office of Environmental Management (EM)

    Study of Factors Affecting Shrub Establishment on the Monticello, Utah, Disposal Cell Cover Study of Factors Affecting Shrub Establishment on the Monticello, Utah, Disposal Cell...

  18. EO 13211: Regulations That Significantly Affect Energy Supply...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EO 13211: Regulations That Significantly Affect Energy Supply, Distribution, or Use EO 13211: Regulations That Significantly Affect Energy Supply, Distribution, or Use I am...

  19. Polycyclic aromatic hydrocarbon-DNA adducts and the CYP1A1 restriction fragment length polymorphism

    SciTech Connect (OSTI)

    Shields, P.G.; Bowman, E.D.; Weston, A.; Harris, C.C.; Sugimura, H.; Caporaso, N.E.; Petruzzelli, S.F. ); Trump, B.F. )

    1992-11-01

    Human cancer risk assessment at a genetic level involves the investigation of carcinogen metabolism and DNA adduct formation. Wide interindividual differences in metabolism result in different DNA adduct levels. For this and other reasons, many laboratories have considered DNA adducts to be a measure of the biologically effective dose of a carcinogen. Techniques for studying DNA adducts using chemically specific assays are becoming available. A modification of the [sup 32]P-postlabeling assay for polycyclic aromatic hydrocarbon DNA adducts described here provides potential improvements in quantification. DNA adducts, however, reflect only recent exposure to carcinogens; in contrast, genetic testing for metabolic capacity indicates the extent to which carcinogens can be activated and exert genotoxic effects. Such studies may reflect both separate and integrated risk factors together with DNA adduct levels. A recently described restriction fragment length polymorphism for the CYP1A1, which codes for the cytochrome P450 enzyme primarily responsible for the metabolic activation of carcinogenic polycyclic aromatic hydrocarbons, has been found to be associated with lung cancer risk in a Japanese population. In a subset of individuals enrolled in a US lung cancer case-control study, no association with lung cancer was found. 17 refs., 3 figs.

  20. Raidiation-Induced Fragmentation of Diamide Extraction Agents in Ionic Liquid Diluents

    SciTech Connect (OSTI)

    Bell, Jason R; Dai, Sheng; Shkrob, Ilya A.; Marin, Timothy W.; Luo, Huimin; Hatcher, Jasmine; Rimmer, R. Dale; Wishart, James F.

    2012-01-01

    N,N,N',N'-Tetraalkyldiglycolamides are extracting agents that are used for liquid-liquid extraction of trivalent metal ions in wet processing of spent nuclear fuel. This application places such agents in contact with the decaying radionuclides, causing radiolysis of the agent in the organic diluent. Recent research seeks to replace common molecular diluents (such as n-dodecane) with hydrophobic room-temperature ionic liquids (ILs), which have superior solvation properties. In alkane diluents, rapid radiolytic deterioration of diglycolamide agents can be inhibited by addition of an aromatic cosolvent that scavenges highly reactive alkane radical cations before these oxidize the extracting agent. Do aromatic ILs exhibit a similar radioprotective effect? To answer this question, we used electron paramagnetic resonance spectroscopy to study the fragmentation pathways in radiolysis of neat diglycolamides, their model compounds, and their solutions in the ILs. Our study indicates that aromatic ILs do not protect these types of solutes from extensive radiolytic damage. Previous research indicated a similar lack of protection for crown ethers, whereas the ILs readily protected di- and trialkyl phosphates (another large class of metal-extracting agents). Our analysis of these unanticipated failures suggests that new types of organic anions are required in order to formulate ILs capable of radioprotection for these classes of solutes. This study is a cautionary tale of the fallacy of analogical thinking when applied to an entirely new and insufficiently understood class of chemical materials.

  1. The melting temperature of liquid water with the effective fragment potential

    SciTech Connect (OSTI)

    Brorsen, Kurt R.; Willow, Soohaeng Y.; Xantheas, Sotiris S.; Gordon, Mark S.

    2015-09-17

    Direct simulation of the solid-liquid water interface with the effective fragment potential (EFP) via the constant enthalpy and pressure (NPH) ensemble was used to estimate the melting temperature (Tm) of ice-Ih. Initial configurations and velocities, taken from equilibrated constant pressure and temperature (NPT) simulations at T = 300 K, 350 K and 400 K, respectively, yielded corresponding Tm values of 37816 K, 38214 K and 38415 K. These estimates are consistently higher than experiment, albeit to the same degree with previously reported estimates using density functional theory (DFT)-based Born-Oppenheimer simulations with the Becke-Lee-Yang-Parr functional plus dispersion corrections (BLYP-D). KRB was supported by a Computational Science Graduate Fellowship from the Department of Energy. MSG was supported by a U.S. National Science Foundation Software Infrastructure (SI2) grant (ACI 1047772). SSX acknowledges support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.

  2. Structures of Minimal Catalytic Fragments of Topoisomerase V Reveals Conformational Changes Relevant for DNA Binding

    SciTech Connect (OSTI)

    Rajan, Rakhi; Taneja, Bhupesh; Mondragn, Alfonso

    2010-12-03

    Topoisomerase V is an archaeal type I topoisomerase that is unique among topoisomerases due to presence of both topoisomerase and DNA repair activities in the same protein. It is organized as an N-terminal topoisomerase domain followed by 24 tandem helix-hairpin-helix (HhH) motifs. Structural studies have shown that the active site is buried by the (HhH) motifs. Here we show that the N-terminal domain can relax DNA in the absence of any HhH motifs and that the HhH motifs are required for stable protein-DNA complex formation. Crystal structures of various topoisomerase V fragments show changes in the relative orientation of the domains mediated by a long bent linker helix, and these movements are essential for the DNA to enter the active site. Phosphate ions bound to the protein near the active site helped model DNA in the topoisomerase domain and show how topoisomerase V may interact with DNA.

  3. The Linearly Scaling 3D Fragment Method for Large Scale Electronic Structure Calculations

    SciTech Connect (OSTI)

    Zhao, Zhengji; Meza, Juan; Lee, Byounghak; Shan, Hongzhang; Strohmaier, Erich; Bailey, David; Wang, Lin-Wang

    2009-06-26

    The Linearly Scaling three-dimensional fragment (LS3DF) method is an O(N) ab initio electronic structure method for large-scale nano material simulations. It is a divide-and-conquer approach with a novel patching scheme that effectively cancels out the artificial boundary effects, which exist in all divide-and-conquer schemes. This method has made ab initio simulations of thousand-atom nanosystems feasible in a couple of hours, while retaining essentially the same accuracy as the direct calculation methods. The LS3DF method won the 2008 ACM Gordon Bell Prize for algorithm innovation. Our code has reached 442 Tflop/s running on 147,456 processors on the Cray XT5 (Jaguar) at OLCF, and has been run on 163,840 processors on the Blue Gene/P (Intrepid) at ALCF, and has been applied to a system containing 36,000 atoms. In this paper, we will present the recent parallel performance results of this code, and will apply the method to asymmetric CdSe/CdS core/shell nanorods, which have potential applications in electronic devices and solar cells.

  4. The linearly scaling 3D fragment method for large scale electronic structure calculations

    SciTech Connect (OSTI)

    Zhao, Zhengji; Meza, Juan; Lee, Byounghak; Shan, Hongzhang; Strohmaier, Erich; Bailey, David; Wang, Lin-Wang

    2009-07-28

    The Linearly Scaling three-dimensional fragment (LS3DF) method is an O(N) ab initio electronic structure method for large-scale nano material simulations. It is a divide-and-conquer approach with a novel patching scheme that effectively cancels out the artificial boundary effects, which exist in all divide-and-conquer schemes. This method has made ab initio simulations of thousand-atom nanosystems feasible in a couple of hours, while retaining essentially the same accuracy as the direct calculation methods. The LS3DF method won the 2008 ACM Gordon Bell Prize for algorithm innovation. Our code has reached 442 Tflop/s running on 147,456 processors on the Cray XT5 (Jaguar) at OLCF, and has been run on 163,840 processors on the Blue Gene/P (Intrepid) at ALCF, and has been applied to a system containing 36,000 atoms. In this paper, we will present the recent parallel performance results of this code, and will apply the method to asymmetric CdSe/CdS core/shell nanorods, which have potential applications in electronic devices and solar cells.

  5. A short Id2 protein fragment containing the nuclear export signal forms amyloid-like fibrils

    SciTech Connect (OSTI)

    Colombo, Noemi [Fakultaet fuer Chemie und Pharmazie, Universitaet Regensburg, Universitaetsstrasse 31, 93053 Regensburg (Germany); Schroeder, Josef [Institut fuer Pathologie, Zentrales EM-Labor, Fakultaet fuer Medizin, Universitaet Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg (Germany); Cabrele, Chiara [Fakultaet fuer Chemie und Pharmazie, Universitaet Regensburg, Universitaetsstrasse 31, 93053 Regensburg (Germany)]. E-mail: chiara.cabrele@chemie.uni-regensburg.de

    2006-07-21

    The negative regulator of DNA-binding/cell-differentiation Id2 is a small protein containing a central helix-loop-helix (HLH) motif and a C-terminal nuclear export signal (NES). Whereas the former is essential for Id2 dimerization and nuclear localization, the latter is responsible for the transport of Id2 from the nucleus to the cytoplasm. Whereas the isolated Id2 HLH motif is highly helical, large C-terminal Id2 fragments including the NES sequence are either unordered or aggregation-prone. To study the conformational properties of the isolated NES region, we synthesized the Id2 segment 103-124. The latter was insoluble in water and only temporarily soluble in water/alcohol mixtures, where it formed quickly precipitating {beta}-sheets. Introduction of a positively charged N-terminal tail prevented aggressive precipitation and led to aggregates consisting of long fibrils that bound thioflavin T. These results show an interesting structural aspect of the Id2 NES region, which might be of significance for both protein folding and function.

  6. A Survey of lamba Repressor Fragments from Two-State to to Downhill Folding

    SciTech Connect (OSTI)

    Liu, F.; Gao, Y; Gruebele, M

    2010-01-01

    We survey the two-state to downhill folding transition by examining 20 {lambda}{sub 6-85}* mutants that cover a wide range of stabilities and folding rates. We investigated four new {lambda}{sub 6-85}* mutants designed to fold especially rapidly. Two were engineered using the core remodeling of Lim and Sauer, and two were engineered using Ferreiro et al.'s frustratometer. These proteins have probe-dependent melting temperatures as high as 80 C and exhibit a fast molecular phase with the characteristic temperature dependence of the amplitude expected for downhill folding. The survey reveals a correlation between melting temperature and downhill folding previously observed for the {beta}-sheet protein WW domain. A simple model explains this correlation and predicts the melting temperature at which downhill folding becomes possible. An X-ray crystal structure with a 1.64-{angstrom} resolution of a fast-folding mutant fragment shows regions of enhanced rigidity compared to the full wild-type protein.

  7. Hydroprocessing conditions affect catalyst shape selection

    SciTech Connect (OSTI)

    Cooper, B.H.; Donnis, B.B.L.; Moyse, B.

    1986-12-08

    Diffusion characteristics, pressure drop limitations, catalyst pore size, catalyst loading techniques, and catalytic activity requirements all affect the selection of the catalyst shape used in hydroprocessing of heavy distillates. Haldor Topsoe Inc. has studied the effects of these hydroprocessing conditions on various shapes of its TK-551 nickel-molybdenum hydroprocessing catalysts. The studies were carried out using Arabian Heavy vacuum gas oil (VGO). For hydroprocessing heavy distillates, polylobed catalysts and dense loading techniques have obvious advantages. The higher external surface of polylobed catalysts ensures better accessibility to the inner surface of the catalyst, and dense loading allows more catalytic activity in a given reactor volume. However there are drawbacks. Polylobed catalysts tend to pack less densely thus reducing volume activity. And dense loading results in higher pressure through the bed. The philosophy behind the use of polylobed catalysts is to improve the diffusion characteristics.

  8. Cylinder surface, temperature may affect LPG odorization

    SciTech Connect (OSTI)

    McWilliams, H.

    1988-01-01

    A study of possible odorant fade in propane by the Arthur D. Little Co. (Boston) has indicated that oxidation of interior surfaces of LPG containers may cause the odorant, ethyl mercaptan, to fade. The oxidation, ferous oxide, is a black, easily oxidizable powder that is the monoxide of iron. The study, contracted for by the Consumer Product Safety Commission (CPSC), is part of that agency's study of residential LP-gas systems. Another study is currently underway by an NLPGA task force headed by Bob Reid of Petrolane (Long Beach, Calif.). It may not be finished until the end of next year. Recently, the Propane Gas Association of Canada completed a study of odorant fade with the conclusion that much more study is needed on the subject. In addition to the cylinder surface problem, the CPSC study indicated that ambient temperatures might also affect the presence of odorant in product. This article reviews some of the results.

  9. Mechanisms affecting swelling in alloys with precipitates

    SciTech Connect (OSTI)

    Mansur, L.K.; Haynes, M.R.; Lee, E.H.

    1980-01-01

    In alloys under irradiation many mechanisms exist that couple phase instability to cavity swelling. These are compounded with the more familiar mechanisms associated with point defect behavior and the evolution of microstructure. The mechanisms may be classified according to three modes of operation. Some affect cavity swelling directly by cavity-precipitate particle association, others operate indirectly by precipitate-induced changes in sinks other than cavities and finally there are mechanisms that are mediated by precipitate-induced changes in the host matrix. The physics of one mechanism of each type is developed in detail and the results compared where possible to experimental measurements. In particular, we develop the theory necessary to treat the effects on swelling of precipitation-induced changes in overall sink density; precipitation-induced changes in point defect trapping by solute depletion and creation of precipitate particle-matrix interfacial trap sites.

  10. Various factors affect coiled tubing limits

    SciTech Connect (OSTI)

    Yang, Y.S.

    1996-01-15

    Safety and reliability remain the primary concerns in coiled tubing operations. Factors affecting safety and reliability include corrosion, flexural bending, internal (or external) pressure and tension (or compression), and mechanical damage due to improper use. Such limits as coiled tubing fatigue, collapse, and buckling need to be understood to avoid disaster. With increased use of coiled tubing, operators will gain more experience. But at the same time, with further research and development of coiled tubing, the manufacturing quality will be improved and fatigue, collapse, and buckling models will become more mature, and eventually standard specifications will be available. This paper reviews the uses of coiled tubing and current research on mechanical behavior of said tubing. It also discusses several models used to help predict fatigue and failure levels.

  11. Assisting Federal Facilities with Energy Conservation Technologies (AFFECT)

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Funding Opportunity | Department of Energy Project Financing » Assisting Federal Facilities with Energy Conservation Technologies (AFFECT) Funding Opportunity Assisting Federal Facilities with Energy Conservation Technologies (AFFECT) Funding Opportunity The Federal Energy Management Program (FEMP) provides project assistance through the AFFECT funding opportunity. AFFECT provides grants for the development of capital projects to increase the energy efficiency and renewable energy

  12. Fragmentation of the adenine and guanine molecules induced by electron collisions

    SciTech Connect (OSTI)

    Minaev, B. F. E-mail: boris@theochem.kth.se; Shafranyosh, M. I.; Svida, Yu. Yu; Sukhoviya, M. I.; Shafranyosh, I. I.; Baryshnikov, G. V.; Minaeva, V. A.

    2014-05-07

    Secondary electron emission is the most important stage in the mechanism of radiation damage to DNA biopolymers induced by primary ionizing radiation. These secondary electrons ejected by the primary electron impacts can produce further ionizations, initiating an avalanche effect, leading to genome damage through the energy transfer from the primary objects to sensitive biomolecular targets, such as nitrogenous bases, saccharides, and other DNA and peptide components. In this work, the formation of positive and negative ions of purine bases of nucleic acids (adenine and guanine molecules) under the impact of slow electrons (from 0.1 till 200 eV) is studied by the crossed electron and molecular beams technique. The method used makes it possible to measure the molecular beam intensity and determine the total cross-sections for the formation of positive and negative ions of the studied molecules, their energy dependences, and absolute values. It is found that the maximum cross section for formation of the adenine and guanine positive ions is reached at about 90 eV energy of the electron beam and their absolute values are equal to 2.8 10{sup ?15} and 3.2 10{sup ?15} cm{sup 2}, respectively. The total cross section for formation of the negative ions is 6.1 10{sup ?18} and 7.6 10{sup ?18} cm{sup 2} at the energy of 1.1 eV for adenine and guanine, respectively. The absolute cross-section values for the molecular ions are measured and the cross-sections of dissociative ionization are determined. Quantum chemical calculations are performed for the studied molecules, ions and fragments for interpretation of the crossed beams experiments.

  13. N-Terminal Enrichment: Developing a Protocol to Detect Specific Proteolytic Fragments

    SciTech Connect (OSTI)

    Schepmoes, Athena A.; Zhang, Qibin; Petritis, Brianne O.; Qian, Weijun; Smith, Richard D.

    2009-12-01

    Proteolytic processing events are essential to physiological processes such as reproduction, development, and host responses, as well as regulating proteins in cancer; therefore, there is a significant need to develop robust approaches for characterizing such events. The current mass spectrometry (MS)-based proteomics techniques employs a “bottom-up” strategy, which does not allow for identification of different proteolytic proteins since the strategy measures all the small peptides from any given protein. The aim of this development is to enable the effective identification of specific proteolytic fragments. The protocol utilizes an acetylation reaction to block the N-termini of a protein, as well as any lysine residues. Following digestion, N-terminal peptides are enriched by removing peptides that contain free amines, using amine-reactive silica-bond succinic anhydride beads. The resulting enriched sample has one N-terminal peptide per protein, which reduces sample complexity and allows for increased analytical sensitivity compared to global proteomics.1 We initially compared the peptide identification and efficiency of blocking lysine using acetic anhydride (a 42 Da modification) or propionic anhydride (a 56 Da modification) in our protocol. Both chemical reactions resulted in comparable peptide identifications and *95 percent efficiency for blocking lysine residues. However, the use of propionic anhydride allowed us to distinguish in vivo acetylated peptides from chemically-tagged peptides.2 In an initial experiment using mouse plasma, we were able to identify *300 unique N-termini peptides, as well as many known cleavage sites. This protocol holds potential for uncovering new information related to proteolytic pathways, which will assist our understanding about cancer biology and efforts to identify potential biomarkers for various diseases.

  14. Interaction of toluene with two-color asymmetric laser fields: Controlling the directional emission of molecular hydrogen fragments

    SciTech Connect (OSTI)

    Kaziannis, S.; Kotsina, N.; Kosmidis, C.

    2014-09-14

    The interaction of toluene with strong asymmetric two-color laser irradiation of 40 fs duration is studied by means of Time of flight mass spectrometry. Highly energetic H{sub 2}{sup +} and H{sub 3}{sup +} fragment ions are produced through an isomerization process taking place within transient multiply charged parent ions. Comparative study of deuterium labeled toluene isotopes enables the discrimination between molecular hydrogen fragments formed exclusively within the CH{sub 3}- part from those that require hydrogen atom exchange between the former and the phenyl moiety. It is demonstrated that by manipulating the relative phase of the ω/2ω field components the selective ionization of oriented toluene molecules can be used as a tool to control the directional emission of the H{sub 2}{sup +}, H{sub 3}{sup +} species.

  15. COLLAPSE AND FRAGMENTATION OF MAGNETIC MOLECULAR CLOUD CORES WITH THE ENZO AMR MHD CODE. I. UNIFORM DENSITY SPHERES

    SciTech Connect (OSTI)

    Boss, Alan P.; Keiser, Sandra A.

    2013-02-20

    Magnetic fields are important contributors to the dynamics of collapsing molecular cloud cores, and can have a major effect on whether collapse results in a single protostar or fragmentation into a binary or multiple protostar system. New models are presented of the collapse of magnetic cloud cores using the adaptive mesh refinement code Enzo2.0. The code was used to calculate the ideal magnetohydrodynamics (MHD) of initially spherical, uniform density, and rotation clouds with density perturbations, i.e., the Boss and Bodenheimer standard isothermal test case for three-dimensional (3D) hydrodynamics codes. After first verifying that Enzo reproduces the binary fragmentation expected for the non-magnetic test case, a large set of models was computed with varied initial magnetic field strengths and directions with respect to the cloud core axis of rotation (parallel or perpendicular), density perturbation amplitudes, and equations of state. Three significantly different outcomes resulted: (1) contraction without sustained collapse, forming a denser cloud core; (2) collapse to form a single protostar with significant spiral arms; and (3) collapse and fragmentation into binary or multiple protostar systems, with multiple spiral arms. Comparisons are also made with previous MHD calculations of similar clouds with a barotropic equations of state. These results for the collapse of initially uniform density spheres illustrate the central importance of both magnetic field direction and field strength for determining the outcome of dynamic protostellar collapse.

  16. Collapse and fragmentation of magnetic molecular cloud cores with the Enzo AMR MHD code. II. Prolate and oblate cores

    SciTech Connect (OSTI)

    Boss, Alan P.; Keiser, Sandra A.

    2014-10-10

    We present the results of a large suite of three-dimensional models of the collapse of magnetic molecular cloud cores using the adaptive mesh refinement code Enzo2.2 in the ideal magnetohydrodynamics approximation. The cloud cores are initially either prolate or oblate, centrally condensed clouds with masses of 1.73 or 2.73 M {sub ?}, respectively. The radial density profiles are Gaussian, with central densities 20 times higher than boundary densities. A barotropic equation of state is used to represent the transition from low density isothermal phases, to high density optically thick phases. The initial magnetic field strength ranges from 6.3 to 100 ?G, corresponding to clouds that are strongly to marginally supercritical, respectively, in terms of the mass to magnetic flux ratio. The magnetic field is initially uniform and aligned with the clouds' rotation axes, with initial ratios of rotational to gravitational energy ranging from 10{sup 4} to 0.1. Two significantly different outcomes for collapse result: (1) formation of single protostars with spiral arms, and (2) fragmentation into multiple protostar systems. The transition between these two outcomes depends primarily on the initial magnetic field strength, with fragmentation occurring for mass to flux ratios greater than about 14 times the critical ratio for prolate clouds. Oblate clouds typically fragment into several times more clumps than prolate clouds. Multiple, rather than binary, system formation is the general rule in either case, suggesting that binary stars are primarily the result of the orbital dissolution of multiple protostar systems.

  17. Fragmentation mechanisms for methane induced by 55 eV, 75 eV, and 100 eV electron impact

    SciTech Connect (OSTI)

    Wei, B.; Zhang, Y.; Wang, X. Lu, D.; Lu, G. C.; Hutton, R.; Zou, Y.; Institute of Modern Physics, Department of Nuclear Science and Technology, Fudan University, Shanghai 200433 ; Zhang, B. H.; Tang, Y. J.

    2014-03-28

    The fragmentation of CH{sub 4}{sup 2+} dications following 55 eV, 75 eV, and 100 eV electron impact double ionization of methane was studied using a cold target recoil-ion momentum spectroscopy. From the measured momentum of each recoil ion, the momentum of the neutral particles has been deduced and the kinetic energy release distribution for the different fragmentation channels has been obtained. The doubly charged molecular ions break up into three or more fragments in one or two-step processes, resulting in different signatures in the data. We observed the fragmentation of CH{sub 4}{sup 2+} dications through different mechanisms according to the momentum of the neutral particles. For example, our result shows that there are three reaction channels to form CH{sub 2}{sup +}, H{sup +}, and H, one synchronous concerted reaction channel and two two-step reaction channels. For even more complicated fragmentation processes of CH{sub 4}{sup 2+} dications, the fragmentation mechanism can still be identified in the present measurements. The slopes of the peak in the ion-ion coincidence spectra were also estimated here, as they are also related to the fragmentation mechanism.

  18. Recombination enhances HIV-1 envelope diversity by facilitating the survival of latent genomic fragments in the plasma virus population

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Immonen, Taina T.; Conway, Jessica M.; Romero-Severson, Ethan O.; Perelson, Alan S.; Leitner, Thomas; Kouyos, Roger Dimitri

    2015-12-22

    HIV-1 is subject to immune pressure exerted by the host, giving variants that escape the immune response an advantage. Virus released from activated latent cells competes against variants that have continually evolved and adapted to host immune pressure. Nevertheless, there is increasing evidence that virus displaying a signal of latency survives in patient plasma despite having reduced fitness due to long-term immune memory. We investigated the survival of virus with latent envelope genomic fragments by simulating within-host HIV-1 sequence evolution and the cycling of viral lineages in and out of the latent reservoir. Our model incorporates a detailed mutation processmore » including nucleotide substitution, recombination, latent reservoir dynamics, diversifying selection pressure driven by the immune response, and purifying selection pressure asserted by deleterious mutations. We evaluated the ability of our model to capture sequence evolution in vivo by comparing our simulated sequences to HIV-1 envelope sequence data from 16 HIV-infected untreated patients. Empirical sequence divergence and diversity measures were qualitatively and quantitatively similar to those of our simulated HIV-1 populations, suggesting that our model invokes realistic trends of HIV-1 genetic evolution. Moreover, reconstructed phylogenies of simulated and patient HIV-1 populations showed similar topological structures. Our simulation results suggest that recombination is a key mechanism facilitating the persistence of virus with latent envelope genomic fragments in the productively infected cell population. Recombination increased the survival probability of latent virus forms approximately 13-fold. Prevalence of virus with latent fragments in productively infected cells was observed in only 2% of simulations when we ignored recombination, while the proportion increased to 27% of simulations when we allowed recombination. We also found that the selection pressures exerted by different

  19. Unrestricted density functional theory based on the fragment molecular orbital method for the ground and excited state calculations of large systems

    SciTech Connect (OSTI)

    Nakata, Hiroya; RIKEN, Research Cluster for Innovation, Nakamura Lab, 2-1 Hirosawa, Wako, Saitama 351-0198 ; Fedorov, Dmitri G.; Yokojima, Satoshi; Tokyo University of Pharmacy and Life Sciences, 1423-1 Horinouchi, Hachioji-shi, Tokyo 192-0392 ; Kitaura, Kazuo; Sakurai, Minoru; Nakamura, Shinichiro

    2014-04-14

    We extended the fragment molecular orbital (FMO) method interfaced with density functional theory (DFT) into spin unrestricted formalism (UDFT) and developed energy gradients for the ground state and single point excited state energies based on time-dependent DFT. The accuracy of FMO is evaluated in comparison to the full calculations without fragmentation. Electronic excitations in solvated organic radicals and in the blue copper protein, plastocyanin (PDB code: 1BXV), are reported. The contributions of solvent molecules to the electronic excitations are analyzed in terms of the fragment polarization and quantum effects such as interfragment charge transfer.

  20. Measurement of the reaction cross section of {sup 18}C and observations of fragments from {sup 17}C and {sup 18}C at 80A MeV

    SciTech Connect (OSTI)

    Ozawa, A.; Fang, D. Q.; Fukuda, M.; Iwasa, N.; Izumikawa, T.; Jeppesen, H.; Kanungo, R.; Koyama, R.; Ohtsubo, T.; Shinozaki, W.; Takahashi, M.; Ohnishi, T.; Suda, T.; Yamaguchi, Y.; Suzuki, T.; Tanihata, I.; Wu, C.

    2008-11-15

    The one- and two-neutron removal reactions from {sup 17}C and {sup 18}C as well as the reaction cross section of {sup 18}C have been studied using a carbon target at 80A MeV. The longitudinal momentum distributions of {sup 15,16}C fragments from {sup 17}C and {sup 16,17}C fragments from {sup 18}C were measured by a direct time-of-flight method. The width of {sup 15}C fragments from {sup 17}C is fairly smaller than that from other C isotopes. The experimental data are discussed within the framework of the Glauber model.

  1. Enhanced Oil Recovery Affects the Future Energy Mix | GE Global...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enhanced Oil Recovery Affects the Future Energy Mix Click to email this to a friend (Opens ... Enhanced Oil Recovery Affects the Future Energy Mix Trevor Kirsten 2012.11.19 One of the ...

  2. AFFECT 2016: Assisting Federal Facilities with Energy Conservation

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technologies Webinar | Department of Energy AFFECT 2016: Assisting Federal Facilities with Energy Conservation Technologies Webinar AFFECT 2016: Assisting Federal Facilities with Energy Conservation Technologies Webinar Webinar describes the 2016 Assisting Federal Facilities with Energy Conservation Technologies (AFFECT) funding opportunity offered by the Federal Energy Management Program. View the webinar slides.

  3. Effects of Neutron Emission on Fragment Mass and Kinetic Energy Distribution from Thermal Neutron-Induced Fission of {sup 235}U

    SciTech Connect (OSTI)

    Montoya, M.; Rojas, J.; Saetone, E.

    2007-10-26

    The mass and kinetic energy distribution of nuclear fragments from thermal neutron-induced fission of {sup 235}U(n{sub th},f) have been studied using a Monte-Carlo simulation. Besides reproducing the pronounced broadening in the standard deviation of the kinetic energy at the final fragment mass number around m = 109, our simulation also produces a second broadening around m = 125. These results are in good agreement with the experimental data obtained by Belhafaf et al. and other results on yield of mass. We conclude that the obtained results are a consequence of the characteristics of the neutron emission, the sharp variation in the primary fragment kinetic energy and mass yield curves. We show that because neutron emission is hazardous to make any conclusion on primary quantities distribution of fragments from experimental results on final quantities distributions.

  4. A behaviorally-explicit approach for delivering vaccine baits to mesopredators to control epizootics in fragmented landscapes

    SciTech Connect (OSTI)

    Beasley, James C.; Atwood, Todd C.; Byrne, Michael E.; Vercauteren, Kurt C.; Johnson, Shylo R.; Olin E. Rhodes, Jr.; Schnell, Matthias Johannes

    2015-01-14

    Despite the widespread use of aerial baiting to manage epizootics among free-ranging populations,particularly in rabies management, bait acceptance and seroconversion rates often are lower than required to eliminate spread of disease. Our objectives in this study, therefore, were to evaluate the performance of stratified bait distribution models derived from resource selection functions (RSF) on uptake of placebo rabies baits by raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana), as well as the probability of bait uptake as a function of proximity to bait distribution areas in fragmented agricultural ecosystems. Among 478 raccoons and 108 opossums evaluated for presence of Rhodamine B (RB) across 8 sites, only 26% of raccoons and 20% of opossums exhibited marking consistent with bait consumption 14–24 days post-baiting. The effective area treated, based on 90% kernel density estimators of marked individuals, ranged from 99–240 ha larger than bait distribution zones, with RB marked individuals captured up to 753m beyond the bait zone. Despite incorporation of RSF data into bait distribution models, no differences in uptake rates were observed between treatment and control sites. These data likely reflect the underlying constraints imposed by the loss and fragmentation of habitat on animal movement in heterogeneous landscapes, forcing individuals to optimize movements at coarse (i.e., patch-level) rather than fine spatial scales in highly fragmented environments. Our data also confirm that the probability of bait acceptance decreases with increasing distance from bait zone interiors, even within the zone itself. Thus, although bait acceptance was confirmed beyond bait zone boundaries, the proportion of vaccinated individuals may comprise a small minority of the population at increasing distances from baiting interiors. These data suggest focal baiting creates a buffered area of treated individuals around bait zones or bait stations

  5. The effect of oxygen-to-fuel stoichiometry on coal ash fine-fragmentation mode formation mechanisms.

    SciTech Connect (OSTI)

    Fix, G.; Seames, W. S.; Mann, M. D.; Benson, S. A.; Miller, D. J.

    2011-04-01

    Ash particles smaller than 2.5 {micro}m in diameter generated during pulverized coal combustion are difficult to capture and may pose greater harm to the environment and human health than the discharge of larger particles. Recent research efforts on coal ash formation have revealed a middle fine-fragment mode centered around 2 {micro}m. Formation of this middle or fine-fragment mode (FFM) is less well understood compared to larger coarse and smaller ultrafine ash. This study is part of an overall effort aimed at determining the key factors that impact the formation of FFM. This work examined the effects of oxygen-to-fuel stoichiometry (OFS). Pulverized Illinois No.6 bituminous coal was combusted and the ash generated was size segregated in a Dekati low pressure inertial impactor. The mass of each fraction was measured and the ash was analyzed using scanning electron microscopy (SEM) and X-ray microanalysis. The FFM ash types were classified based on the SEM images to evaluate the significant fine-fragment ash formation mechanisms and determine any possible link between stoichiometry and formation mechanism. From the particle size distributions (PSDs), the coarse mode appears unaffected by the change in OFS, however, the OFS 1.05 lowered the fraction of ultrafine ash in relation to the higher OFS settings, and appears to increase the portion of the FFM. An intermediate minimum was found in the FFM at 1.3 {micro}m for the 1.20 and 1.35 OFS tests but was not observed in the 1.05 OFS. SEM analysis also suggests that OFS may contribute to changing formation mechanisms.

  6. A behaviorally-explicit approach for delivering vaccine baits to mesopredators to control epizootics in fragmented landscapes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Beasley, James C.; Atwood, Todd C.; Byrne, Michael E.; Vercauteren, Kurt C.; Johnson, Shylo R.; Olin E. Rhodes, Jr.; Schnell, Matthias Johannes

    2015-01-14

    Despite the widespread use of aerial baiting to manage epizootics among free-ranging populations,particularly in rabies management, bait acceptance and seroconversion rates often are lower than required to eliminate spread of disease. Our objectives in this study, therefore, were to evaluate the performance of stratified bait distribution models derived from resource selection functions (RSF) on uptake of placebo rabies baits by raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana), as well as the probability of bait uptake as a function of proximity to bait distribution areas in fragmented agricultural ecosystems. Among 478 raccoons and 108 opossums evaluated for presence of Rhodaminemore » B (RB) across 8 sites, only 26% of raccoons and 20% of opossums exhibited marking consistent with bait consumption 14–24 days post-baiting. The effective area treated, based on 90% kernel density estimators of marked individuals, ranged from 99–240 ha larger than bait distribution zones, with RB marked individuals captured up to 753m beyond the bait zone. Despite incorporation of RSF data into bait distribution models, no differences in uptake rates were observed between treatment and control sites. These data likely reflect the underlying constraints imposed by the loss and fragmentation of habitat on animal movement in heterogeneous landscapes, forcing individuals to optimize movements at coarse (i.e., patch-level) rather than fine spatial scales in highly fragmented environments. Our data also confirm that the probability of bait acceptance decreases with increasing distance from bait zone interiors, even within the zone itself. Thus, although bait acceptance was confirmed beyond bait zone boundaries, the proportion of vaccinated individuals may comprise a small minority of the population at increasing distances from baiting interiors. These data suggest focal baiting creates a buffered area of treated individuals around bait zones or bait stations, but

  7. Inferring Group Processes from Computer-Mediated Affective Text Analysis

    SciTech Connect (OSTI)

    Schryver, Jack C; Begoli, Edmon; Jose, Ajith; Griffin, Christopher

    2011-02-01

    Political communications in the form of unstructured text convey rich connotative meaning that can reveal underlying group social processes. Previous research has focused on sentiment analysis at the document level, but we extend this analysis to sub-document levels through a detailed analysis of affective relationships between entities extracted from a document. Instead of pure sentiment analysis, which is just positive or negative, we explore nuances of affective meaning in 22 affect categories. Our affect propagation algorithm automatically calculates and displays extracted affective relationships among entities in graphical form in our prototype (TEAMSTER), starting with seed lists of affect terms. Several useful metrics are defined to infer underlying group processes by aggregating affective relationships discovered in a text. Our approach has been validated with annotated documents from the MPQA corpus, achieving a performance gain of 74% over comparable random guessers.

  8. Position reconstruction in fission fragment detection using the low pressure MWPC technique for the JLab experiment E02-017

    SciTech Connect (OSTI)

    Xi-Yu, Qiu; Tang, Liguang; Margaryan, Amur T.; Jin-Zhang, Xu; Bi-Tao, Hu; Xi-Meng, Chen

    2014-07-01

    When a lambda hyperon was embedded in a nucleus, it can form a hypernucleus. The lifetime and its mass dependence of stable hypernuclei provide information about the weak decay of lambda hyperon inside nuclear medium. This work will introduce the Jefferson Lab experiment (E02-017) which aims to study the lifetime of the heavy hypernuclei using a specially developed fission fragment detection technique, a multi-wire proportional chamber operated under low gas pressure (LPMWPC). Presented here are the method and performance of the reconstruction of fission position on the target foil, the separation of target materials at different regions and the comparison and verification with the Mote Carlo simulation.

  9. Dynamical description of the moments of the energy distribution of fission fragments and scission of a fissile nucleus

    SciTech Connect (OSTI)

    Borunov, M. V., E-mail: bmv@opsb.ru; Nadtochy, P. N.; Adeev, G. D. [Omsk State University (Russian Federation)

    2007-11-15

    A multidimensional stochastic approach to fission dynamics on the basis of three-dimensional Langevin equations is applied systematically to calculating the first four moments of the energy distribution of fission fragments over a broad range of Coulomb parameter values (700 < Z{sup 2}/A{sup 1/3} < 1700). For the scission of a fissile nucleus into fragments, use was made of various criteria traditional in modern fission theory: the vanishing of the neck radius at the scission instant and the equality of the neck radius to about 0.3R{sub 0} at this instant. In calculating the energy distribution, both of the criteria used lead to a fairly good description of experimental data on the first two moments and to a satisfactory description of data on the third and fourth moments of the distribution. However, the quality of the description of available experimental data is insufficiently good for giving preference to any of these criteria. Within three-dimensional Langevin dynamics, it is shown that the vanishing-radius criterion leads to unexpectably good agreement with experimental data on the first four moments of the energy distribution. A modified version of one-body dissipation where the coefficient that takes into account the reduction of the wall-formula contribution was set to k{sub s} = 0.25 was used in the calculations.

  10. FEMP's Assisting Federal Facilities with Energy Conservation Technologies (AFFECT)

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFFECT 2016 Assisting Federal Facilities with Energy Conservation Technologies (AFFECT) June 8, 2016 David Boomsma AFFECT Program Manager Federal Energy Management Program (FEMP) Energy Efficiency and Renewable Energy Department of Energy Federal Energy Management Program 2 Event Date FOA Issue Date May 26, 2016 Letter of Intent (LOI) Deadline June 27, 2016 5:00pm ET Full Application Deadline July 27, 2016 5:00pm ET Notification of Award Selections October 28, 2016 Timeframe for Award

  11. Key Parameters Affecting DPF Performance Degradation and Impact on Lifetime

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Fuel Economy | Department of Energy Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy Key Parameters Affecting DPF Performance Degradation and Impact on Lifetime Fuel Economy Summarizes latest findings on impact of specific parameters affecting ash-related diesel particulate filter performance degradation and information useful to enhance performance and extend service life deer11_sappok.pdf (3.32 MB) More Documents & Publications Characteristics and

  12. Water-related Issues Affecting Conventional Oil and Gas Recovery...

    Office of Scientific and Technical Information (OSTI)

    Water-related Issues Affecting Conventional Oil and Gas Recovery and Potential Oil-Shale Development in the Uinta Basin, Utah Michael Vanden Berg; Paul Anderson; Janae Wallace;...

  13. Factors Affecting Power Output by Photovoltaic Cells Lesson

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Factors Affecting Power Output by Photovoltaic Cells Grade Level(s): IB 2 (Senior - 3 ... C.8 Photovoltaic cells and dye-sensitized solar cells (DSSC) Understandings: * Solar ...

  14. Ecosystem carbon storage capacity as affected by disturbance...

    Office of Scientific and Technical Information (OSTI)

    and tausub 1 is the residence time of the carbon pool affected by disturbances (biomass pool in this study). The disturbance regime is characterized by the mean disturbance...

  15. Fact #890: September 14, 2015 Gasoline Prices Are Affected by...

    Broader source: Energy.gov (indexed) [DOE]

    Gasoline Prices Are Affected by Changes in Refinery Output File fotw890web.xlsx More Documents & Publications Fact 858 February 2, 2015 Retail Gasoline Prices in 2014 ...

  16. The microbe-mediated mechanisms affecting topsoil carbon stock...

    Office of Scientific and Technical Information (OSTI)

    affecting topsoil carbon stock in Tibetan grasslands Warming has been shown to cause soil carbon (C) loss in northern grasslands owing to accelerated microbial decomposition...

  17. An in-situ phosphorus source for the synthesis of Cu3P and the subsequent conversion to Cu3PS4 nanoparticle clusters

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sheets, Erik J.; Stach, Eric A.; Yang, Wei -Chang; Balow, Robert B.; Wang, Yunjie; Walker, Bryce C.; Agrawal, Rakesh

    2015-09-20

    The search for alternative earth abundant semiconducting nanocrystals for sustainable energy applications has brought forth the need for nanoscale syntheses beyond bulk synthesis routes. Of particular interest are metal phosphides and derivative I-V-VI chalcogenides including copper phosphide (Cu3P) and copper thiophosphate (Cu3PS4). Herein, we report a one-pot, solution-based synthesis of Cu3P nanocrystals utilizing an in-situ phosphorus source: phosphorus pentasulfide (P2S5) in trioctylphosphine (TOP). By injecting this phosphorus source into a copper solution in oleylamine (OLA), uniform and size controlled Cu3P nanocrystals with a phosphorous-rich surface are synthesized. The subsequent reaction of the Cu3P nanocrystals with decomposing thiourea forms nanoscale Cu3PS4more » particles having p-type conductivity and an effective optical band gap of 2.36 eV.« less

  18. A method to calculate fission-fragment yields Y(Z,N) versus proton and neutron number in the Brownian shape-motion model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Moller, Peter; Ichikawa, Takatoshi

    2015-12-23

    In this study, we propose a method to calculate the two-dimensional (2D) fission-fragment yield Y(Z,N) versus both proton and neutron number, with inclusion of odd-even staggering effects in both variables. The approach is to use the Brownian shape-motion on a macroscopic-microscopic potential-energy surface which, for a particular compound system is calculated versus four shape variables: elongation (quadrupole moment Q2), neck d, left nascent fragment spheroidal deformation ϵf1, right nascent fragment deformation ϵf2 and two asymmetry variables, namely proton and neutron numbers in each of the two fragments. The extension of previous models 1) introduces a method to calculate this generalizedmore » potential-energy function and 2) allows the correlated transfer of nucleon pairs in one step, in addition to sequential transfer. In the previous version the potential energy was calculated as a function of Z and N of the compound system and its shape, including the asymmetry of the shape. We outline here how to generalize the model from the “compound-system” model to a model where the emerging fragment proton and neutron numbers also enter, over and above the compound system composition.« less

  19. Set up of an experimental apparatus for the study of fragmentation of solid fuels upon severe heating

    SciTech Connect (OSTI)

    Senneca, O.; Allouis, C.; Chirone, R.; Russo, S.

    2010-04-15

    An experimental apparatus has been developed in order to perform tests of primary fragmentation of solid fuels under severe heating conditions. The device is a modified heated strip reactor, capable to reach 2000 C in less than 0.2 s. Particles are laid on the strip and pyrolysed under inert or moderately oxidizing conditions. The char particles and their fragments, generated upon pyrolysis, can be recovered and analysed to assess the fragmentation propensity of the fuel. Some preliminary experiments have been carried out on two biomass samples in order to assess the time-temperature history of particles in the experimental apparatus. In particular biomass particles of approximately 2-3 mm have been used. The temperature of the heated strip reactor in such preliminary tests was varied between 1000 and 1600 C, while the strip nominal heating rate was kept at 10{sup 4} C/s and the holding time was set at the value of 10 s. A near infrared fast camera (38,000 frames/s) has been used to measure the temperature of the heated strip and of the particles during the tests. A heat up model was developed and validated against experimental results. The model was then used to estimate the temperature gradients across particles of biomass and of coal as well. Results show that the strip of the reactor reaches the set temperature in less than 0.2 s. When particles are laid on the strip, their bottom surface, which is in physical contact with the strip, immediately reaches the set temperature value. For 1 mm coal particles the upper surface can be considered at the same temperature as well. Under the most severe conditions tested (strip temperature of 1600 C, biomass particles of 2 mm thickness) the temperature difference between the bottom and the upper face is 200 C after 3 s and drops to 100 C after 10 s. On the whole the experimental apparatus simulates uniform heating of the particles with reasonable approximation. In the next future the apparatus will be further upgraded to

  20. Cells with dysfunctional telomeres are susceptible to reactive oxygen species hydrogen peroxide via generation of multichromosomal fusions and chromosomal fragments bearing telomeres

    SciTech Connect (OSTI)

    Woo, Seon Rang; Department of Biochemistry, College of Medicine, Korea University, Seoul 136-705 ; Park, Jeong-Eun; Juhn, Kyoung-Mi; Ju, Yeun-Jin; Jeong, Jaemin; Kang, Chang-Mo; Yun, Hyun Jin; Yun, Mi Yong; Shin, Hyun-Jin; Joo, Hyun-Yoo; Park, Eun-Ran; Park, In-Chul; Hong, Sung Hee; Hwang, Sang-Gu; Kim, Haekwon; Cho, Myung-Haing; Kim, Sang Hoon; Park, Gil Hong; Lee, Kee-Ho

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Under conditions of telomere erosion, cells become extremely sensitive to H{sub 2}O{sub 2}. Black-Right-Pointing-Pointer Chromosomal regions adjacent to telomeres are cleaved by H{sub 2}O{sub 2} under such conditions. Black-Right-Pointing-Pointer H{sub 2}O{sub 2} thus causes multichromosomal fusions and generation of small chromosomal fragments. Black-Right-Pointing-Pointer N-acetylcysteine prevents H{sub 2}O{sub 2}-induced chromosomal aberrations. -- Abstract: During genotoxic stress, reactive oxygen species hydrogen peroxide (H{sub 2}O{sub 2}) is a prime mediator of the DNA damage response. Telomeres function both to assist in DNA damage repair and to inhibit chromosomal end-to-end fusion. Here, we show that telomere dysfunction renders cells susceptible to H{sub 2}O{sub 2}, via generation of multichromosomal fusion and chromosomal fragments. H{sub 2}O{sub 2} caused formation of multichromosomal end-to-end fusions involving more than three chromosomes, preferentially when telomeres were erosive. Interestingly, extensive chromosomal fragmentation (yielding small-sized fragments) occurred only in cells exhibiting such multichromosomal fusions. Telomeres were absent from fusion points, being rather present in the small fragments, indicating that H{sub 2}O{sub 2} cleaves chromosomal regions adjacent to telomeres. Restoration of telomere function or addition of the antioxidant N-acetylcysteine prevented development of chromosomal aberrations and rescued the observed hypersensitivity to H{sub 2}O{sub 2}. Thus, chromosomal regions adjacent to telomeres become sensitive to reactive oxygen species hydrogen peroxide when telomeres are dysfunctional, and are cleaved to produce multichromosomal fusions and small chromosomal fragments bearing the telomeres.

  1. Preliminary Scoping and Assessment Study of the Potential Impacts of Community-wide Radiological Events and Subsequent Decontamination Activities on Drinking Water and Wastewater Systems

    SciTech Connect (OSTI)

    Monette, F.A.; Biwer, B.M.; Tomasko, D.; Chen, S.Y.; Hais, A.; MacKinney, J.; Janke, R.

    2006-07-01

    Since the terrorist attacks of September 11, 2001, there has been a great deal of concern about further attacks within the United States, particularly attacks using weapons of mass destruction (WMD) or other unconventional weapons, such as a radiological dispersal device (RDD) or 'dirty bomb', which is a type of RDD. During all phases of an RDD event, secondary impacts on drinking water and wastewater systems would be possible. Secondary impacts refer to those impacts that would occur when the water systems were not the direct or intended target of the specific event. Secondary impacts would include (1) fallout from an event occurring elsewhere on water supply reservoirs and (2) runoff into storm water and sewer systems during precipitation events or as a result of cleanup and decontamination activities. To help address potential secondary impacts, a scoping and assessment study was conducted for the U.S. Environmental Protection Agency's National Homeland Security Research Center to support its water security program. The study addresses the potential impacts on water resources and infrastructure that could result from the use of an RDD, including potential impacts from the initial attack as well as from subsequent cleanup efforts. Eight radionuclides are considered in the assessment: Am-241, Cf-252, Cs-137, Co-60, Ir-192, Pu-238, Ra-226, and Sr-90. (authors)

  2. Water-related Issues Affecting Conventional Oil and Gas Recovery...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Water-related Issues Affecting Conventional Oil and Gas Recovery and Potential Oil-Shale Development in the Uinta Basin, Utah Citation Details In-Document Search ...

  3. Water-related Issues Affecting Conventional Oil and Gas Recovery...

    Office of Scientific and Technical Information (OSTI)

    Water-related Issues Affecting Conventional Oil and Gas Recovery and Potential Oil-Shale Development in the Uinta Basin, Utah Citation Details In-Document Search Title: Water-re...

  4. How the Koontz Decision May Affect Climate Change Policy

    Broader source: Energy.gov [DOE]

    Please join us for a Sept. 10 webinar to discuss the Supreme Court's controversial decision in Koontz v. St. Johns River Water Management District and explore how the decision may affect the...

  5. Water-related Issues Affecting Conventional Oil and Gas Recovery...

    Office of Scientific and Technical Information (OSTI)

    Water-related Issues Affecting Conventional Oil and Gas Recovery and Potential Oil-Shale Development in the Uinta Basin, Utah Citation Details In-Document Search Title: Water-relat...

  6. Factors Affecting HCCI Combustion Phasing for Fuels with Single- and

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Dual-Stage Chemistry | Department of Energy Affecting HCCI Combustion Phasing for Fuels with Single- and Dual-Stage Chemistry Factors Affecting HCCI Combustion Phasing for Fuels with Single- and Dual-Stage Chemistry 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Sandia National Laboratories 2004_deer_dec.pdf (185.71 KB) More Documents & Publications Microsoft PowerPoint - DEER03-P.ppt HCCI and Stratified-Charge CI Engine Combustion Research Improving Efficiency

  7. A Systematic Investigation of Parameters Affecting Diesel NOx Adsorber

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalyst Performance | Department of Energy A Systematic Investigation of Parameters Affecting Diesel NOx Adsorber Catalyst Performance A Systematic Investigation of Parameters Affecting Diesel NOx Adsorber Catalyst Performance 2002 DEER Conference Presentation: Dephi Corporation 2002_deer_dou.pdf (121.2 KB) More Documents & Publications Pt-free, Perovskite-based Lean NOx Trap Catalysts Use of a Diesel Fuel Processor for Rapid and Efficient Regeneration of Single Leg NOx Adsorber Systems

  8. One in five online scholarly articles affected by 'reference rot'

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scholarly articles affected by 'reference rot' One in five online scholarly articles affected by 'reference rot' Los Alamos authors focus on reference rot, the combination of link rot and content drift to which references to web resources included in STM articles are subject. January 26, 2015 From left, Los Alamos National Laboratory authors Lyudmila Balakireva, Herbert Van De Sompel and Harihar Shankar, and Martin Klein and Robert Sanderson (on computer screens). Their work was published in the

  9. SUSTAINABILITY NEWS Assisting Federal Facilities with Energy Conservation Technologies (AFFECT)

    Energy Savers [EERE]

    Assisting Federal Facilities with Energy Conservation Technologies (AFFECT) DOE's Federal Energy Management Program (FEMP) recently issued a notice of intent to release a Funding Opportunity Announcement (FOA) for its new AFFECT program. The program intends to provide direct funding awards of up to $1 million per project to help finance renewable energy and combined heat and power (CHP) projects. Projects that apply for the funding are expected to leverage other financing mechanisms (such as

  10. Federal Energy Management Program Issues 2016 AFFECT Funding Opportunity

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Announcement | Department of Energy Federal Energy Management Program Issues 2016 AFFECT Funding Opportunity Announcement Federal Energy Management Program Issues 2016 AFFECT Funding Opportunity Announcement May 25, 2016 - 5:26pm Addthis On May 26, 2016, the Federal Energy Management Program (FEMP) issued a Funding Opportunity Announcement (FOA) on the EERE Exchange titled Assisting Federal Facilities with Energy Conservation Technologies 2016. The Assisting Federal Facilities with Energy

  11. Azimuthal correlations of projectile and target fragments in collisions between gold nuclei of energy 10.6 GeV per nucleon and emulsion nuclei

    SciTech Connect (OSTI)

    Abdurakhmanov, U. U.; Gulamov, K. G.; Zhokhova, S. I.; Lugovoi, V. V. Navotny, V. Sh. Chudakov, V. M.

    2008-03-15

    Intra-and intergroup azimuthal correlations of projectile and target fragments are found in collisions between gold and emulsion nuclei. The statistical significance of these correlations is high. The methodological distortions associated with the measurement errors are investigated in detail and are taken into account.

  12. Molecular transformations of phenolic SOA during photochemical aging in the aqueous phase: competition among oligomerization, functionalization, and fragmentation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, L.; Smith, J.; Laskin, A.; George, K. M.; Anastasio, C.; Laskin, J.; Dillner, A. M.; Zhang, Q.

    2015-10-30

    Organic aerosol is formed and transformed in atmospheric aqueous phases (e.g., cloud and fog droplets and deliquesced airborne particles containing small amounts of water) through a multitude of chemical reactions. Understanding these reactions is important for a predictive understanding of atmospheric aging of aerosols and their impacts on climate, air quality, and human health. In this study, we investigate the chemical evolution of aqueous secondary organic aerosol (aqSOA) formed during reactions of phenolic compounds with two oxidants the triplet excited state of an aromatic carbonyl (3C*) and hydroxyl radical (OH). Changes in the molecular composition of aqSOA as amorefunction of aging time are characterized using an offline nanospray desorption electrospray ionization mass spectrometer (nano-DESI MS) whereas the real-time evolution of SOA mass, elemental ratios, and average carbon oxidation state (OSC) are monitored using an online aerosol mass spectrometer (AMS). Our results indicate that oligomerization is an important aqueous reaction pathway for phenols, especially during the initial stage of photooxidation equivalent to ? 2 h irradiation under midday, winter solstice sunlight in northern California. At later reaction times functionalization (i.e., adding polar oxygenated functional groups to the molecule) and fragmentation (i.e., breaking of covalent bonds) become more important processes, forming a large variety of functionalized aromatic and open-ring products with higher OSC values. Fragmentation reactions eventually dominate the photochemical evolution of phenolic aqSOA, forming a large number of highly oxygenated open-ring molecules with carbon numbers (nC) below 6. The average nC of phenolic aqSOA decreases while average OSC increases over the course of photochemical aging. In addition, the saturation vapor pressures C*) of dozens of the most abundant phenolic aqSOA molecules are estimated. A wide range of C* values is observed

  13. Molecular transformations of phenolic SOA during photochemical aging in the aqueous phase: competition among oligomerization, functionalization, and fragmentation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, Lu; Smith, Jeremy; Laskin, Alexander; George, Katheryn M.; Anastasio, Cort; Laskin, Julia; Dillner, Ann M.; Zhang, Qi

    2016-04-13

    Organic aerosol is formed and transformed in atmospheric aqueous phases (e.g., cloud and fog droplets and deliquesced airborne particles containing small amounts of water) through a multitude of chemical reactions. Understanding these reactions is important for a predictive understanding of atmospheric aging of aerosols and their impacts on climate, air quality, and human health. In this study, we investigate the chemical evolution of aqueous secondary organic aerosol (aqSOA) formed during reactions of phenolic compounds with two oxidants – the triplet excited state of an aromatic carbonyl (3C∗) and hydroxyl radical (•OH). Changes in the molecular composition of aqSOA as amore » function of aging time are characterized using an offline nanospray desorption electrospray ionization mass spectrometer (nano-DESI MS) whereas the real-time evolution of SOA mass, elemental ratios, and average carbon oxidation state (OSC) are monitored using an online aerosol mass spectrometer (AMS). Our results indicate that oligomerization is an important aqueous reaction pathway for phenols, especially during the initial stage of photooxidation equivalent to  ∼  2 h irradiation under midday winter solstice sunlight in Northern California. At later reaction times functionalization (i.e., adding polar oxygenated functional groups to the molecule) and fragmentation (i.e., breaking of covalent bonds) become more important processes, forming a large variety of functionalized aromatic and open-ring products with higher OSC values. Fragmentation reactions eventually dominate the photochemical evolution of phenolic aqSOA, forming a large number of highly oxygenated ring-opening molecules with carbon numbers (nC) below 6. The average nC of phenolic aqSOA decreases while average OSC increases over the course of photochemical aging. In addition, the saturation vapor pressures (C∗) of dozens of the most abundant phenolic aqSOA molecules are estimated. A wide range of C∗ values

  14. Factors affecting degradation of polyethylene terephthalate (PET) during pre-flotation conditioning

    SciTech Connect (OSTI)

    Caparanga, Alvin R. Basilia, Blessie A.; Dagbay, Kevin B.; Salvacion, Jonathan W.L.

    2009-09-15

    In general, plastics are exposed to different degrading agents in every procedure involved in their recovery from waste mixture and from subsequent recycling. In this study, two methods of pre-flotation conditioning were used to determine how these methods affect the general properties of the pre-conditioned PET particles to be recovered from the PET-PVC mixture. The first method comprised the conditioning of PET samples using an alkaline solution of nonionic surfactant (Triton X-100) based on the patent by the Goodyear Tire and Rubber Company. The second method, developed in this study, was a conditioning process which used an alkali-less solution of the same nonionic surfactant (Triton X-100) used in the first method. The following analytical methods were used to characterize properties of the pre-conditioned PET samples that were correlated to relative degradation of the samples: differential scanning calorimetry (DSC), for thermal behavior of the samples; FT-IR spectroscopy, for functional groups present in the samples; and, Pohl's method, for carboxyl end-group concentration count. Results show that in addition to water the presence of NaOH in the conditioning solution contributes to the further degradation of the polymer.

  15. STS map of genes and anonymous DNA fragments on human chromosome 18 using a panel of somatic cell hybrids

    SciTech Connect (OSTI)

    Overhauser, J.; Mewar, R.; Rojas, K.; Kline, A.D. ); Lia, K.; Silverman, G.A. )

    1993-02-01

    Somatic cell hybrids containing different deleted regions of chromosome 18 derived form patients with balanced translocations or terminal deletions were used to create a deletion mapping panel. Twenty-four sequence-tagged sites (STSs) for 17 genes and 7 anonymous polymorphic DNA fragments were identified. These STSs were used to map the 24 loci to 18 defined regions of chromosome 18. Both ERV1, previously mapped to 18q22-q23, and YES1, previously mapped to 18q21.3, were found to map to 18p11.21-pter. Several genes previously mapped to 18q21 were found to be in the order cen-SSAV1-DCC-FECH-GRP-BCL2-PLANH2-tel. The precise mapping of genes to chromosome 18 should help in determining whether these genes may be involved in the etiology of specific chromosomal syndromes associated with chromosome 18. The mapping of the poloymorphic loci will assist in the integration of the physical map with the recombination map of chromosome 18. 43 refs., 2 figs., 1 tab.

  16. Silanol-assisted carbinolamine formation in an amine-functionalized mesoporous silica surface: Theoretical investigation by fragmentation methods

    SciTech Connect (OSTI)

    de Lima Batista, Ana P.; Zahariev, Federico; Slowing, Igor I.; Braga, Ataualpa A. C.; Ornellas, Fernando R.; Gordon, Mark S.

    2015-12-15

    The aldol reaction catalyzed by an amine-substituted mesoporous silica nanoparticle (amine-MSN) surface was investigated using a large molecular cluster model (Si392O958C6NH361) combined with the surface integrated molecular orbital/molecular mechanics (SIMOMM) and fragment molecular orbital (FMO) methods. Three distinct pathways for the carbinolamine formation, the first step of the amine-catalyzed aldol reaction, are proposed and investigated in order to elucidate the role of the silanol environment on the catalytic capability of the amine-MSN material. The computational study reveals that the most likely mechanism involves the silanol groups actively participating in the reaction, forming and breaking covalent bonds in the carbinolamine step. Furthermore, the active participation of MSN silanol groups in the reaction mechanism leads to a significant reduction in the overall energy barrier for the carbinolamine formation. In addition, a comparison between the findings using a minimal cluster model and the Si392O958C6NH361 cluster suggests that the use of larger models is important when heterogeneous catalysis problems are the target.

  17. Crystal structure of P58(IPK) TPR fragment reveals the mechanism for its molecular chaperone activity in UPR

    SciTech Connect (OSTI)

    Tao, Jiahui; Petrova, Kseniya; Ron, David; Sha, Bingdong (UAB); (NYUSM)

    2010-05-25

    P58(IPK) might function as an endoplasmic reticulum molecular chaperone to maintain protein folding homeostasis during unfolded protein responses. P58(IPK) contains nine tetratricopeptide repeat (TPR) motifs and a C-terminal J-domain within its primary sequence. To investigate the mechanism by which P58(IPK) functions to promote protein folding within the endoplasmic reticulum, we have determined the crystal structure of P58(IPK) TPR fragment to 2.5 {angstrom} resolution by the SAD method. The crystal structure of P58(IPK) revealed three domains (I-III) with similar folds and each domain contains three TPR motifs. An ELISA assay indicated that P58(IPK) acts as a molecular chaperone by interacting with misfolded proteins such as luciferase and rhodanese. The P58(IPK) structure reveals a conserved hydrophobic patch located in domain I that might be involved in binding the misfolded polypeptides. Structure-based mutagenesis for the conserved hydrophobic residues located in domain I significantly reduced the molecular chaperone activity of P58(IPK).

  18. Silanol-assisted carbinolamine formation in an amine-functionalized mesoporous silica surface: Theoretical investigation by fragmentation methods

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    de Lima Batista, Ana P.; Zahariev, Federico; Slowing, Igor I.; Braga, Ataualpa A. C.; Ornellas, Fernando R.; Gordon, Mark S.

    2015-12-15

    The aldol reaction catalyzed by an amine-substituted mesoporous silica nanoparticle (amine-MSN) surface was investigated using a large molecular cluster model (Si392O958C6NH361) combined with the surface integrated molecular orbital/molecular mechanics (SIMOMM) and fragment molecular orbital (FMO) methods. Three distinct pathways for the carbinolamine formation, the first step of the amine-catalyzed aldol reaction, are proposed and investigated in order to elucidate the role of the silanol environment on the catalytic capability of the amine-MSN material. The computational study reveals that the most likely mechanism involves the silanol groups actively participating in the reaction, forming and breaking covalent bonds in the carbinolamine step.more » Furthermore, the active participation of MSN silanol groups in the reaction mechanism leads to a significant reduction in the overall energy barrier for the carbinolamine formation. In addition, a comparison between the findings using a minimal cluster model and the Si392O958C6NH361 cluster suggests that the use of larger models is important when heterogeneous catalysis problems are the target.« less

  19. Research Finds Vitamin D Deficiency Affects Bone Quality

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research Finds Vitamin D Deficiency Affects Bone Quality Research Finds Vitamin D Deficiency Affects Bone Quality Print Wednesday, 30 April 2014 00:00 Vitamin D deficiency is a widespread medical condition that plays a major role in human bone health. Scientists know that a lack of vitamin D can cause bone diseases such as rickets and osteomalacia. Now a team of researchers working at the ALS has also found that vitamin D deficiency plays a significant role in the bone-aging process. Low levels

  20. Study of Chelyabinsk LL5 meteorite fragment with a light lithology and its fusion crust using Mssbauer spectroscopy with a high velocity resolution

    SciTech Connect (OSTI)

    Maksimova, Alevtina A.; Petrova, Evgeniya V.; Grokhovsky, Victor I.; Oshtrakh, Michael I. Semionkin, Vladimir A.

    2014-10-27

    Study of Chelyabinsk LL5 ordinary chondrite fragment with a light lithology and its fusion crust, fallen on February 15, 2013, in Russian Federation, was carried out using Mssbauer spectroscopy with a high velocity resolution. The Mssbauer spectra of the internal matter and fusion crust were fitted and all components were related to iron-bearing phases such as olivine, pyroxene, troilite, Fe-Ni-Co alloy, and chromite in the internal matter and olivine, pyroxene, troilite, Fe-Ni-Co alloy, and magnesioferrite in the fusion crust. A comparison of the content of different phases in the internal matter and in the fusion crust of this fragment showed that ferric compounds resulted from olivine, pyroxene, and troilite combustion in the atmosphere.

  1. D{sup 0}, D{sup +}, D{sub s}{sup +}, and {lambda}{sub c}{sup +} fragmentation functions from CERN LEP1

    SciTech Connect (OSTI)

    Kniehl, Bernd A.; Kramer, Gustav

    2005-05-01

    We present new sets of nonperturbative fragmentation functions for D{sup 0}, D{sup +}, and D{sub s}{sup +} mesons as well as for {lambda}{sub c}{sup +} baryons, both at leading and next-to-leading order in the MS factorization scheme with five massless quark flavors. They are determined by fitting data of e{sup +}e{sup -} annihilation taken by the OPAL Collaboration at CERN LEP1. We take the charm-quark fragmentation function to be of the form proposed by Peterson et al. and thus obtain new values of the {epsilon}{sub c} parameter, which are specific for our choice of factorization scheme.

  2. Simulation of dependence of the cross section of deuterons beam fragmentation into cumulative pions and protons on the mass of the target nucleus

    SciTech Connect (OSTI)

    Litvinenko, A. G.; Litvinenko, E. I.

    2015-03-15

    We have studied the mechanisms influencing production of cumulative pions and protons in the fragmentation of the incident deuterons into cumulative pions and protons emitted at zero angle. We argue that the peripheral dependence on the atomic mass of the target nucleus, which was obtained in the experiments for medium and heavy nuclei, can be explained by scattering on target nucleons without introducing additional parameters.

  3. Investigation of the reaction {sup 208}Pb({sup 18}O, f): Folding angular distributions of fission fragments and gamma-ray multiplicity

    SciTech Connect (OSTI)

    Rusanov, A. Ya. Itkis, M. G.; Kondratiev, N. A.; Pokrovsky, I. V.; Salamatin, V. S.; Chubarian, G. G.

    2007-10-15

    Correlations between folding angular distributions of fission fragments and the gamma-ray multiplicity are studied for {sup 18}O + {sup 208}Pb interactions at energies of the beam of {sup 18}O ions in the range E{sub lab} = 78-198.5 MeV. The probabilities are determined for complete-and incomplete-fusion processes inevitably followed by the fission of nuclei formed in these processes. It is found that the probability of incomplete fusion followed by fission increases with increasing energy of bombarding ions. It is shown that, for the incomplete-fusion process, folding angular distributions of fission fragments have a two-component structure. The width of folding angular distributions (FWHM) for complete fusion grows linearly with increasing energy of {sup 18}O ions. The multiplicity of gamma rays from fission fragments as a function of the linear-momentum transfer behaves differently for different energies of projectile ions. This circumstance is explained here by the distinction between the average angular momenta of participant nuclei in the fusion and fission channels, which is due to the difference in the probabilities of fission in the cases where different numbers of nucleons are captured by the target nucleus.

  4. Measurement of jet fragmentation in PbPb and pp collisions at $\\sqrt{s_{NN}}=2.76$ TeV

    SciTech Connect (OSTI)

    Chatrchyan, Serguei; et al.,

    2014-08-01

    The jet fragmentation function of inclusive jets with transverse momentum pt above 100 GeV in PbPb collisions has been measured using reconstructed charged particles with pt above 1 GeV in a cone of radius 0.3 around the jet axis. A data sample of PbPb collisions collected in 2011 at a nucleon-nucleon center-of-mass energy of sqrt(s[NN]) = 2.76 TeV corresponding to an integrated luminosity of 150 inverse microbarns is used. The results for PbPb collisions as a function of collision centrality and jet transverse momentum are compared to reference distributions based on pp data collected at the same center-of-mass energy in 2013, with an integrated luminosity of 5.3 inverse picobarns. A centrality-dependent modification of the fragmentation function is found. For the most central collisions, a significant enhancement is observed in the PbPb / pp fragmentation function ratio for charged particles with pt less than 3 GeV. This enhancement is observed for all jet pt bins studied.

  5. Characterizing the Range of Extracellular Protein Post-Translational Modifications in a Cellulose-Degrading Bacteria Using a Multiple Proteolyic Digestion/Peptide Fragmentation Approach

    SciTech Connect (OSTI)

    Dykstra, Andrew B; Rodriguez, Jr., Miguel; Raman, Babu; Cook, Kelsey; Hettich, Robert {Bob} L

    2013-01-01

    Post-translational modifications (PTMs) are known to play a significant role in many biological functions. The focus of this study is to characterize the post-translational modifications of the cellulosome protein complex used by the bacterium Clostridium thermocellum to better understand how this protein machine is tuned for enzymatic cellulose solubilization. To enhance comprehensive characterization, the extracellular cellulosome proteins were analyzed using multiple proteolytic digests (trypsin, Lys-C, Glu-C) and multiple fragmentation techniques (collisionally-activated dissociation, electron transfer dissociation, decision tree). As expected, peptide and protein identifications were increased by utilizing alternate proteases and fragmentation methods, in addition to the increase in protein sequence coverage. The complementarity of these experiments also allowed for a global exploration of PTMs associated with the cellulosome based upon a set of defined PTMs that included methylation, oxidation, acetylation, phosphorylation, and signal peptide cleavage. In these experiments, 85 modified peptides corresponding to 28 cellulosome proteins were identified. Many of these modifications were located in active cellulolytic or structural domains of the cellulosome proteins, suggesting a level of possible regulatory control of protein function in various cellulotyic conditions. The use of multiple enzymes and fragmentation technologies allowed for independent verification of PTMs in different experiments, thus leading to increased confidence in PTM identifications.

  6. Predicting Individual Affect of Health Interventions to Reduce HPV Prevalence

    SciTech Connect (OSTI)

    Corley, Courtney D.; Mihalcea, Rada; Mikler, Armin R.; Sanfilippo, Antonio P.

    2011-04-01

    Recently, human papilloma virus has been implicated to cause several throat and oral cancers and hpv is established to cause most cervical cancers. A human papilloma virus vaccine has been proven successful to reduce infection incidence in FDA clinical trials and it is currently available in the United States. Current intervention policy targets adolescent females for vaccination; however, the expansion of suggested guidelines may extend to other age groups and males as well. This research takes a first step towards automatically predicting personal beliefs, regarding health intervention, on the spread of disease. Using linguistic or statistical approaches, sentiment analysis determines a texts affective content. Self-reported HPV vaccination beliefs published in web and social media are analyzed for affect polarity and leveraged as knowledge inputs to epidemic models. With this in mind, we have developed a discrete-time model to facilitate predicting impact on the reduction of HPV prevalence due to arbitrary age and gender targeted vaccination schemes.

  7. Survey of state water laws affecting coal slurry pipeline development

    SciTech Connect (OSTI)

    Rogozen, M.B.

    1980-11-01

    This report summarizes state water laws likely to affect the development of coal slurry pipelines. It was prepared as part of a project to analyze environmental issues related to energy transportation systems. Coal slurry pipelines have been proposed as a means to expand the existing transportation system to handle the increasing coal shipments that will be required in the future. The availability of water for use in coal slurry systems in the coal-producing states is an issue of major concern.

  8. Assessing How Renewables Affect Water Used for Thermoelectric Cooling |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    U.S. DOE Office of Science (SC) Assessing How Renewables Affect Water Used for Thermoelectric Cooling Biological and Environmental Research (BER) BER Home About Research Facilities Science Highlights Searchable Archive of BER Highlights External link Benefits of BER Funding Opportunities Biological & Environmental Research Advisory Committee (BERAC) Community Resources Contact Information Biological and Environmental Research U.S. Department of Energy SC-23/Germantown Building 1000

  9. Process for selectively treating a subterranean formation using coiled tubing without affecting or being affected by the two adjacent zones

    SciTech Connect (OSTI)

    Vercaemer, C.; Lemanczyk, R.; Piot, B.

    1989-06-27

    A process is described for selectively treating a subterranean formation without affecting adjacent zones above and below the formation characterized by: injecting a treatment fluid into a wellbore annulus adjacent the formation to be treated and simultaneously injecting two protection fluids, immiscible with the treatment fluid, into the annulus adjacent the zones wherein the treatment fluid and protection fluids are separated with the wellbore annulus solely by a fluid interface between the treatment fluid and each of the immiscible protection fluids.

  10. Research Finds Vitamin D Deficiency Affects Bone Quality

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research Finds Vitamin D Deficiency Affects Bone Quality Print Vitamin D deficiency is a widespread medical condition that plays a major role in human bone health. Scientists know that a lack of vitamin D can cause bone diseases such as rickets and osteomalacia. Now a team of researchers working at the ALS has also found that vitamin D deficiency plays a significant role in the bone-aging process. Low levels of vitamin D, the "sunshine vitamin," have been previously linked to the