Science.gov

Sample records for 1-4 mw proton

  1. Project X: A Multi-MW Proton Source at Fermilab

    SciTech Connect

    Holmes, Stephen D.; /Fermilab

    2010-05-01

    As the Fermilab Tevatron Collider program draws to a close a strategy has emerged of an experimental program built around the high intensity frontier. The centerpiece of this program is a superconducting H- linac that will support world leading programs in long baseline neutrino experimentation and he study of rare processes. Based on technology shared with the International Linear Collider (ILC), Project X will provide multi-MW beams at 60-120 GeV from the Main Injector, simultaneous with very high intensity beams at lower energies. Project X will also support development of a Muon Collider as a uture facility at the energy frontier.

  2. Beam Loss Studies for the 2-MW LBNE Proton Beam Line

    SciTech Connect

    Drozhdin, A.I.; Childress, S.R.; Mokhov, N.V.; Tropin, I.S.; Zwaska, R.; /Fermilab

    2012-05-01

    Severe limits are put on allowable beam loss during extraction and transport of a 2.3 MW primary proton beam for the Long Baseline Neutrino Experiment (LBNE) at Fermilab. Detailed simulations with the STRUCT and MARS codes have evaluated the impact of beam loss of 1.6 x 10{sup 14} protons per pulse at 120 GeV, ranging from a single pulse full loss to sustained small fractional loss. It is shown that loss of a single beam pulse at 2.3 MW will result in a catastrophic event: beam pipe destruction, damaged magnets and very high levels of residual radiation inside and outside the tunnel. Acceptable beam loss limits have been determined and robust solutions developed to enable efficient proton beam operation under these constraints.

  3. A 10-GeV, 5-MW proton source for a pulsed spallation source

    SciTech Connect

    Cho, Y.; Chae, Y.C.; Crosbie, E.

    1995-12-31

    A feasibility study for a pulsed spallation source based on a 5-MW, 10-GeV rapid proton synchrotron (RCS) is in progress. The integrated concept and performance parameters of the facility are discussed. The 10-GeV synchrotron uses as its injector the 2-GeV accelerator system of a 1-MW source described elsewhere. The 1-MW source accelerator system consists of a 400-MeV H{sup {minus}} linac with 2.5 MeV energy spread in the 75% chopped (25% removed) beam and a 30-Hz RCS that accelerates the 400-MeV beam to 2 GeV. The time averaged current of the accelerator system is 0.5 mA, equivalent to 1.04 {times} 10{sup 14} protons per pulse. The 10-GeV RCS accepts the 2 GeV beam and accelerates it to 10 GeV. Beam transfer from the 2-GeV synchrotron to the 10-GeV machine u highly efficient bunch-to-bucket injection, so that the transfer can be made without beam loss. The synchrotron lattice uses FODO cells of 90{degrees} phase advance. Dispersion-free straight sections are obtained using a missing magnet scheme. The synchrotron magnets are powered by dual-frequency resonant circuits. The magnets are excited at a 20-Hz rate and de-excited at 60-Hz. resulting in an effective 30-Hz rate. A key feature of the design of this accelerator system is that beam losses are minimized from injection to extraction, reducing activation to levels consistent with hands-on maintenance. Details of the study are presented.

  4. Access to enantioenriched alpha-amino esters via rhodium-catalyzed 1,4-addition/enantioselective protonation.

    PubMed

    Navarre, Laure; Martinez, Rémi; Genet, Jean-Pierre; Darses, Sylvain

    2008-05-14

    Conjugate addition of potassium trifluoro(organo)borates 2 to dehydroalanine derivatives 1, mediated by a chiral rhodium catalyst and in situ enantioselective protonation, afforded straightforward access to a variety of protected alpha-amino esters 3 with high yields and enantiomeric excesses up to 95%. Among the tested chiral ligands and proton sources, Binap, in combination with guaiacol (2-methoxyphenol), an inexpensive and nontoxic phenol, afforded the highest asymmetric inductions. Organostannanes have also shown to participate in this reaction. By a fine-tuning of the ester moiety, and using Difluorophos as chiral ligand, increased levels of enantioselectivity, generally close to 95%, were achieved. Deuterium labeling experiments revealed, and DFT calculation supported, an unusual mechanism involving a hydride transfer from the amido substituent to the alpha carbon explaining the high levels of enantioselectivity attained in controlling this alpha chiral center.

  5. Protonation of water clusters in the cavities of acidic zeolites: (H2O)n.H-chabazite, n = 1-4.

    PubMed

    Vener, Mikhail V; Rozanska, Xavier; Sauer, Joachim

    2009-03-21

    Proton forms of zeolite chabazite (H-SSZ-13) loaded with 1 to 4 water molecules per acid site are examined by density functional theory with periodic boundary conditions. Equilibrium structures are determined by localizing minima on the potential energy surface and harmonic vibrational frequencies are calculated. Average structures, proton dynamics and anharmonic spectra at finite temperature (350 K) are determined by molecular dynamics (MD). The protonation state is found to depend on the number of water molecules per acid site (loading) following the trend of increasing proton affinity with increasing cluster size. Single water molecules are not protonated, the protonated water dimer is the most stable equilibrium structure with the PBE functional, but not with BLYP. MD shows that even with PBE, the protonated water dimer is not stable at finite temperature. The protonated water trimer may be formed as a short-lived species, but the protonated water tetramer is the smallest stable protonated cluster. For the same global loading (2 : 1), a heterogeneous distribution of adsorbed water molecules over the cells is more stable than a homogeneous one (1 : 1/3 : 1 vs. 2 : 1/2 : 1 for a double cell), i.e. non-protonated and protonated water clusters may exist simultaneously in polyhydrated H-SSZ13. Adsorption energies (0 K) per water molecule decrease from 71 to 51 kJ mol(-1) for n = 1 to n = 4.

  6. An investigation on the role of vacuolar-type proton pumps and luminal acidity in calcium sequestration by nonmitochondrial and inositol-1,4,5-trisphosphate-sensitive intracellular calcium stores in clonal insulin-secreting cells.

    PubMed

    Bode, H P; Eder, B; Trautmann, M

    1994-06-15

    To test whether in RINm5F rat insulinoma cells luminal acidity and the activity of a vacuolar-type proton pump are involved in calcium sequestration by intracellular calcium stores sensitive to inositol 1,4,5-trisphosphate (InsP3) we examined the effects of various proton-conducting ionophores and ammonium chloride, and of bafilomycin, a specific inhibitor of vacuolar proton pumps, on this parameter. Bafilomycin in concentrations up to 1 microM did not affect calcium sequestration by nonmitochondrial, InsP3-sensitive stores at all; 50 microM carbonylcyanide m-chlorophenylhydrazone, 50 microM monensin and 30 mM NH4Cl, which are diverse ways to dissipate transmembrane pH gradients, did not inhibit calcium sequestration. This argues against signficant involvement of internal acidity and vacuolar proton pumps in calcium sequestration by InsP3-sensitive stores in RINm5F cells. The proton-potassium-exchanging ionophore nigericin (20-100 microM), however, inhibited calcium sequestration by nonmitochondrial and InsP3-sensitive stores. This effect was dependent on the presence of potassium and could be reversed by inclusion of carbonylcyanide m-chlorophenylhydrazone or acetate in the incubation medium. Thus, the inhibitory effect of nigericin appears to be based on proton extrusion coupled to potassium influx across the membrane of calcium stores in RINm5F cells, creating an internal alkalinization of these stores. The effect of nigericin implies the continuous maintenance of an outside-to-inside potassium concentration gradient by nonmitochondrial calcium stores in RINm5F cells. This feature will be of potential interest in the identification of InsP3-sensitive calcium-storing organelles.

  7. Report of the Snowmass M6 Working Group on high intensity proton sources

    SciTech Connect

    Weiren Chou and J. Wei

    2002-08-20

    The U.S. high-energy physics program needs an intense proton source, a 1-4 MW Proton Driver (PD), by the end of this decade. This machine will serve as a stand-alone facility that will provide neutrino superbeams and other high intensity secondary beams such as kaons, muons, neutrons, and anti-protons (cf. E1 and E5 group reports) and also serve as the first stage of a neutrino factory (cf. M1 group report). It can also be a high brightness source for a VLHC. Based on present accelerator technology and project construction experience, it is both feasible and cost-effective to construct a 1-4 MW Proton Driver. Two recent PD design studies have been made, one at FNAL and the other at the BNL. Both designed PD's for 1 MW proton beams at a cost of about U.S. $200M (excluding contingency and overhead) and both designs were upgradeable to 4 MW. An international collaboration between FNAL, BNL and KEK on high intensity proton facilities is addressing a number of key design issues. The superconducting (sc) RF cavities, cryogenics, and RF controls developed for the SNS can be directly adopted to save R&D efforts, cost, and schedule. PD studies are also actively being pursued at Europe and Japan.

  8. Proton bunch compression strategies

    SciTech Connect

    Lebedev, Valeri; /Fermilab

    2009-10-01

    The paper discusses main limitations on the beam power and other machine parameters for a 4 MW proton driver for muon collider. The strongest limitation comes from a longitudinal microwave instability limiting the beam power to about 1 MW for an 8 GeV compressor ring.

  9. Choice of Proton Driver Parameters for a Neutrino Factory

    SciTech Connect

    Kirk,H.G.; Berg, J. S.; Fernow, R. C.; Gallardo, J. C.; Simos, N.; Weng, W.-T.; Brooks, S.

    2006-06-26

    We discuss criteria for designing an optimal 'green field' proton driver for a neutrino factory. The driver parameters are determined by considerations of space charge, power capabilities of the target, beam loading and available RF peak power. A neutrino factory may be the best experimental tool to unravel the physics involved in neutrino oscillation and CP violation phenomena [1]. To have sufficient neutrino flux for acceptable physics results within 5 years requires about 10{sup 22} protons on target per year, which corresponds to 1-4 MW of proton beam power from the proton driver depending on the beam energy. In the past, there were individual proposals from different laboratories of a particular design of proton driver capable of delivering beam power from 2 to 4 MW, without consistent attention paid to the needs or requirements from the downstream systems. In this study, we try to identify the requirements from those down stream systems first, then see whether it is possible to design a proton driver to meet those needs. Such a study will also assist site specific proposals to further improve on their designs to better serve the need of a proton driver for neutrino factory applications.

  10. Targetry issues for the Fermilab 2-MW neutrino superbeam

    SciTech Connect

    Mikhail A Kostin et al.

    2002-06-27

    The possibility to use various target materials are studied for a 2 MW neutrino superbeam facility that can be built at Fermilab utilizing the Main Injector and a Proton Driver. A simple target solution found is a thick graphite rod taking a broad proton beam.

  11. 1,4-Dibromobenzene

    Integrated Risk Information System (IRIS)

    1,4 - Dibromobenzene ; CASRN 106 - 37 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  12. 1,4-Dichlorobenzene

    Integrated Risk Information System (IRIS)

    1,4 - Dichlorobenzene ; CASRN 106 - 46 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinog

  13. 1,4-Dioxane

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 09 / 005 - F www.epa.gov / iris TOXICOLOGICAL REVIEW OF 1,4 - Dioxane ( CAS No . 123 - 91 - 1 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) August 2010 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been rev

  14. 1,4-Dithiane

    Integrated Risk Information System (IRIS)

    1,4 - Dithiane ; CASRN 505 - 29 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  15. Proton/metal-ligand stability constants of complexes of Ni(II), Cu(II), and Co(II) with diethyl 4-(substituted-phenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate in 70% dioxane-water mixture

    NASA Astrophysics Data System (ADS)

    Tekade, Pradip V.; Bajaj, Sonal D.; Thool, Seemita

    2015-12-01

    Physico-chemical properties viz proton-ligand and metal-ligand stability constants of complexes of diethyl 4-(substituted-phenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate with Ni(II), Cu(II), and Co(II) were determined in mixed solvents (70% dioxane). Presence of OH/NH group(s) in these compounds was confirmed at 0.1 M ionic strength in 70% dioxane-water mixture pH-metrically. It is observed that Ni(II), Cu(II), and Co(II) metal ions formed 1: 1 and 1: 2 complex with all the three ligands. The results show that the ratio of log K 1/log K 2 is positive in all cases. This implies that there is little or no steric hindrance to the addition of secondary molecules.

  16. STUDY OF A 10-MW CONTINUOUS SPALLATION NEUTRON SOURCE.

    SciTech Connect

    RUGGIERO,A.G.LUDEWIG,H.SHAPIRO,S.

    2003-05-12

    This paper reports on the feasibility study of a proton Super-Conducting Linac as the driver for an Accelerator-based Continuous Neutron Source (ACNS) [1] to be located at Brookhaven National Laboratory (BNL). The Linac is to be operated in the Continuous Wave (CW) mode to produce an average 10 MW of beam power. The Linac beam energy is taken to be 1.25 GeV. The required average proton beam intensity in exit is then 8 mA.

  17. 20-MW Magnicon for ILC

    SciTech Connect

    Jay L. Hirshfield

    2006-11-29

    The 1.3 GHz RF power to drive ILC is now planned to be supplied by 600-1200, 10-MW peak power multi-beam klystrons. In this project, a conceptual design for 1.3 GHz magnicons with 20 MW peak power was developed as an alternative to the klystrons, with the possibility of cutting in half the numbers of high-power tubes and associated components. Design of a conventional magnicon is described, using TM110 modes in all cavities, as well as design of a modified magnicon with a TE111 mode output cavity. The latter has the advantage of much lower surface fields than the TM110 mode, with no loss of output power or electronic efficiency.

  18. A Muon Source Proton Driver at JPARC-based Parameters

    SciTech Connect

    Neuffer, David

    2016-06-01

    An "ultimate" high intensity proton source for neutrino factories and/or muon colliders was projected to be a ~4 MW multi-GeV proton source providing short, intense proton pulses at ~15 Hz. The JPARC ~1 MW accelerators provide beam at parameters that in many respects overlap these goals. Proton pulses from the JPARC Main Ring can readily meet the pulsed intensity goals. We explore these parameters, describing the overlap and consider extensions that may take a JPARC-like facility toward this "ultimate" source. JPARC itself could serve as a stage 1 source for such a facility.

  19. REPORT OF THE SNOWMASS M6 WORKING GROUP ON HIGH INTENSITY PROTON SOURCES.

    SciTech Connect

    CHOU,W.; WEI,J.

    2001-08-14

    The M6 working group had more than 40 active participants (listed in Section 4). During the three weeks at Snowmass, there were about 50 presentations, covering a wide range of topics associated with high intensity proton sources. The talks are listed in Section 5. This group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), E5 (Fixed-Target Experiments), M1 (Muon Based Systems), T4 (Particle Sources), T5 (Beam dynamics), T7 (High Performance Computing) and T9 (Diagnostics). The M6 group performed a survey of the beam parameters of existing and proposed high intensity proton sources, in particular, of the proton drivers. The results are listed in Table 1. These parameters are compared with the requirements of high-energy physics users of secondary beams in Working Groups E1 and E5. According to the consensus reached in the E1 and E5 groups, the U.S. HEP program requires an intense proton source, a 1-4 MW Proton Driver, by the end of this decade.

  20. Neutronic performance of a benchmark 1-MW LPSS

    SciTech Connect

    Russell, G.J.; Pitcher, E.J.; Ferguson, P.D.

    1995-12-31

    We used split-target/flux-trap-moderator geometry in our 1-MW LPSS computational benchmark performance calculations because the simulation models were readily available. Also, this target/moderator arrangement is a proven LANSCE design and a good neutronic performer. The model has four moderator viewed surfaces, each with a 13x13 cm field-of-view. For our scoping neutronic-performance calculations, we attempted to get as much engineering realism into the target-system mockup as possible. In our present model, we account for target/reflector dilution by cooling; the D{sub 2}O coolant fractions are adequate for 1 MW of 800-MeV protons (1.25 mA). We have incorporated a proton beam entry window and target canisters into the model, as well as (partial) moderator and vacuum canisters. The model does not account for target and moderator cooling lines and baffles, entire moderator canisters, and structural material in the reflector.

  1. AGS UPGRADE TO 1-MW WITH A SUPER CONDUCTING LINAC INJECTOR.

    SciTech Connect

    RUGGIERO,A.GALESSI,J.RAPARIA,D.ROSER,T.WENG,W.

    2003-05-12

    It has been proposed to upgrade the Alternating Gradient Synchrotron (AGS) accelerator complex at the Brookhaven National Laboratory (BNL) to provide an average proton beam power of 1 MW at the energy of 28 GeV. The facility is to be primarily used as a proton driver for the production of intense neutrino beams [l]. This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a new injector to the AGS. The Linac beam energy is 1.3 GeV. The beam intensity is adjusted to provide the required average beam power of 1 MW at 28 GeV. The repetition rate of the SCL-AGS facility is 2.5 beam pulses per second.

  2. Improvement Plans of Fermilab's Proton Accelerator Complex

    SciTech Connect

    Shiltsev, Vladimir

    2016-01-01

    The flagship of Fermilab's long term research program is the Deep Underground Neutrino Experiment (DUNE), located Sanford Underground Research Facility (SURF) in Lead, South Dakota, which will study neutrino oscillations with a baseline of 1300 km. The neutrinos will be produced in the Long Baseline Neutrino Facility (LBNF), a proposed new beam line from Fermilab's Main Injector. The physics goals of the DUNE require a proton beam with a power of some 2.4 MW at 120 GeV, which is roughly four times the current maximum power. Here I discuss current performance of the Fermilab proton accelerator complex, our plans for construction of the SRF proton linac as key part of the Proton Improvement Plan-II (PIP-II), outline the main challenges toward multi-MW beam power operation of the Fermilab accelerator complex and the staged plan to achieve the required performance over the next 15 years.

  3. Proton Therapy

    MedlinePlus

    ... for e-updates Please leave this field empty Proton Therapy SHARE Home > Treatment and Care > Treatments Listen ... a nucleus, which holds two types of particles—protons and neutrons. The nucleus is surrounded by electrons. ...

  4. Enantioselective Protonation

    PubMed Central

    Mohr, Justin T.; Hong, Allen Y.; Stoltz, Brian M.

    2010-01-01

    Enantioselective protonation is a common process in biosynthetic sequences. The decarboxylase and esterase enzymes that effect this valuable transformation are able to control both the steric environment around the proton acceptor (typically an enolate) and the proton donor (typically a thiol). Recently, several chemical methods to achieve enantioselective protonation have been developed by exploiting various means of enantiocontrol in different mechanisms. These laboratory transformations have proven useful for the preparation of a number of valuable organic compounds. PMID:20428461

  5. Preparation and characterization of nanocomposite membranes made of poly(2,6-dimethyl-1,4-phenylene oxide) and montmorillonite for direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Hasani-Sadrabadi, Mohammad Mahdi; Emami, Shahriar Hojjati; Moaddel, Homayoun

    Partially sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) (sulfonated PPO) with various degrees of sulfonation were prepared. The solutions were mixed with organically modified montmorillonite (MMT) to prepare membranes by solvent casting. By increasing the sulfonation degree up to 40% for membranes without MMT, ion exchange capacity, water uptake and proton conductivity reached 2.59 mequiv. g -1, 21% and 0.0182 S cm -1, respectively. The Fourier transfer infrared (FTIR) analysis of sulfonated membranes revealed absorption bands at 1060 and 1100-1300 cm -1 for sulfur-oxygen S dbnd O bonds. X-ray diffraction analysis showed the exfoliated structure of clay in polymeric matrices. A sulfonated PPO/MMT membrane with 27% sulfonation and 2.0 wt% MMT loading showed a membrane selectivity of approximately 63,500 compared to 40,500 for Nafion ® 117, and also a higher power density (125 mW cm -2) than Nafion ® 117 (108 mW cm -2) for single cell DMFC in a 5 M methanol feed.

  6. Development of 2 MW Dummy Load for KSTAR ICH System

    NASA Astrophysics Data System (ADS)

    Kwak, Jong-Gu; Wang, Son Jong; Bae, Young Dug; Yoon, Jae Sung; Hong, Bong Guen

    2005-09-01

    A 2 MW dummy load with a frequency ranging from 30 to 60 MHz is developed for the KSTAR ICH transmitter and the cold test shows that VSWR is less than 1.35 for the temperature variation of 17 °C. DC test also shows that overall temperature increase is less than 3 °C for 400 kW. RF test is done for the RF power of 140 kW and Max. VSWR is about 1.4 at the temperature of 40 °C.

  7. Development of 2 MW Dummy Load for KSTAR ICH System

    SciTech Connect

    Kwak, Jong-Gu; Wang, Son Jong; Bae, Young Dug; Yoon, Jae Sung; Hong, Bong Guen

    2005-09-26

    A 2 MW dummy load with a frequency ranging from 30 to 60 MHz is developed for the KSTAR ICH transmitter and the cold test shows that VSWR is less than 1.35 for the temperature variation of 17 deg. C. DC test also shows that overall temperature increase is less than 3 deg. C for 400 kW. RF test is done for the RF power of 140 kW and Max. VSWR is about 1.4 at the temperature of 40 deg. C.

  8. Development of 70 MW class superconducting generators

    SciTech Connect

    Ohara, T. ); Fukuda, H. ); Ogawa, T.; Shimizu, K.; Shiobara, R. ); Ohi, M. ); Veda, A. ); Itoh, K. ); Taniguchi, H. )

    1991-03-01

    The application of superconductivity technology to electric power apparatuses is very important from the viewpoint of promotion of energy saving and resource saving. Especially the superconducting generators using superconductors as the field windings have many merits compared with conventional generators. Super-GM has been researching and developing 70 MW class model machines since FY 1988 for a scheduled period of eight years, aiming at a 200 MW class superconducting generator. This paper describes the basic designs and the recent R and D situation of 70 MW superconducting generators by Super-GM.

  9. Laser diode pumped 106 mW blue upconversion fiber laser

    NASA Astrophysics Data System (ADS)

    Sanders, S.; Waarts, R. G.; Mehuys, D. G.; Welch, D. F.

    1995-09-01

    A laser diode pumped Tm3+-doped ZBLAN fiber upconversion laser is demonstrated with blue output power levels up to 106 mW. Differential optical-to-optical conversion efficiencies up to 30% are measured with respect to pump power coupled into the upconversion fiber. A single spatial mode blue output beam is demonstrated, with an M2 value of 1.4.

  10. 50 CFR 1.4 - Director.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Director. 1.4 Section 1.4 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS § 1.4 Director. Director means the Director, U.S. Fish and Wildlife Service or the...

  11. 21 CFR 1.4 - Authority citations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Authority citations. 1.4 Section 1.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL GENERAL ENFORCEMENT REGULATIONS General Provisions § 1.4 Authority citations. (a) For each part of its regulations, the Food...

  12. 21 CFR 1.4 - Authority citations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Authority citations. 1.4 Section 1.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL GENERAL ENFORCEMENT REGULATIONS General Provisions § 1.4 Authority citations. (a) For each part of its regulations, the Food...

  13. 45 CFR 1206.1-4 - Suspension.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Suspension. 1206.1-4 Section 1206.1-4 Public... GRANTS AND CONTRACTS-SUSPENSION AND TERMINATION AND DENIAL OF APPLICATION FOR REFUNDING Suspension and Termination of Assistance § 1206.1-4 Suspension. (a) General. The responsible Corporation official may...

  14. 45 CFR 1211.1-4 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Policy. 1211.1-4 Section 1211.1-4 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE VOLUNTEER GRIEVANCE PROCEDURES § 1211.1-4 Policy. It is ACTION's policy to provide volunteers the widest latitude...

  15. 45 CFR 1211.1-4 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Policy. 1211.1-4 Section 1211.1-4 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE VOLUNTEER GRIEVANCE PROCEDURES § 1211.1-4 Policy. It is ACTION's policy to provide volunteers the widest latitude to present their grievances...

  16. 45 CFR 1216.1-4 - Exceptions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Exceptions. 1216.1-4 Section 1216.1-4 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE NONDISPLACEMENT OF EMPLOYED WORKERS AND NONIMPAIRMENT OF CONTRACTS FOR SERVICE § 1216.1-4 Exceptions. (a) The requirements of § 1216.1-3 are...

  17. Catalytic Asymmetric 1,4-Addition Reactions of Simple Alkylnitriles.

    PubMed

    Yamashita, Yasuhiro; Sato, Io; Suzuki, Hirotsugu; Kobayashi, Shū

    2015-10-01

    The development of catalytic asymmetric carbon-carbon bond-forming reactions of alkylnitriles that do not have an activating group at the α-position, under proton-transfer conditions, is a challenging research topic. Here, we report catalytic asymmetric direct-type 1,4-addition reactions of alkylnitriles with α,β-unsaturated amides by using a catalytic amount of potassium hexamethyldisilazide (KHMDS) with a chiral macro crown ether. The desired reactions proceeded in high yields with good diastereo- and enantioselectivities. To our knowledge, this is the first example of catalytic asymmetric direct-type 1,4-addition reaction of alkylnitriles without any activating group at the α-position.

  18. A Pion Production and Capture System for a 4 MW Target Station

    SciTech Connect

    Ding, X.; Kirk, H.; Berg, J.S.

    2010-06-01

    A study of a pion production and capture system for a 4 MW target station for a neutrino factory or muon collider is presented. Using the MARS code, we simulate the pion production produced by the interaction of a free liquid mercury jet with an intense proton beam. We study the variation of meson production with the direction of the proton beam relative to the target. We also examine the influence on the meson production by the focusing of the proton beam. The energy deposition in the capture system is determined and the shielding required in order to avoid radiation damage is discussed. The exploration for the multiple proton beam entry directions relative to mercury jet in the 8GeV proton beam case demonstrates that an asymmetric layout is required in order to achieve the same beam/jet crossing angle at the jet axis. We find a correlation between the distance of beam relative to the jet and the meson production. The peak meson production is 8% higher than for the lowest case. The examination of the influence on the meson production by the focusing of the proton beam shows the meson production loss is negligible (<1%) for a beta function to be 0.3m or higher for the proton beam. By investigating the energy deposition in the target/capture system, we see that the bulk of 4-MW proton beam power is deposited in the water cooled tungsten-carbide (WC) shielding, the mercury jet and the capture beam pipe. In addition, high power deposition in the first superconducting coil causes an issue for its operation and life time. Enhanced shielding is necessary to lower the radiation damage.

  19. 5 MW pulsed spallation neutron source, Preconceptual design study

    SciTech Connect

    Not Available

    1994-06-01

    This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in {approx} 1 {mu}sec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs.

  20. Proton Transport

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The transport of protons across membranes is an essential process for both bioenergetics of modern cells and the origins of cellular life. All living systems make use of proton gradients across cell walls to convert environmental energy into a high-energy chemical compound, adenosine triphosphate (ATP), synthesized from adenosine diphosphate. ATP, in turn, is used as a source of energy to drive many cellular reactions. The ubiquity of this process in biology suggests that even the earliest cellular systems were relying on proton gradient for harvesting environmental energy needed to support their survival and growth. In contemporary cells, proton transfer is assisted by large, complex proteins embedded in membranes. The issue addressed in this Study was: how the same process can be accomplished with the aid of similar but much simpler molecules that could have existed in the protobiological milieu? The model system used in the study contained a bilayer membrane made of phospholipid, dimyristoylphosphatidylcholine (DMPC) which is a good model of the biological membranes forming cellular boundaries. Both sides of the bilayer were surrounded by water which simulated the environment inside and outside the cell. Embedded in the membrane was a fragment of the Influenza-A M$_2$ protein and enough sodium counterions to maintain system neutrality. This protein has been shown to exhibit remarkably high rates of proton transport and, therefore, is an excellent model to study the formation of proton gradients across membranes. The Influenza M$_2$ protein is 97 amino acids in length, but a fragment 25 amino acids long. which contains a transmembrane domain of 19 amino acids flanked by three amino acids on each side. is sufficient to transport protons. Four identical protein fragments, each folded into a helix, aggregate to form small channels spanning the membrane. Protons are conducted through a narrow pore in the middle of the channel in response to applied voltage. This

  1. Design of 250-MW CW RF system for APT

    SciTech Connect

    Rees, D.

    1997-09-01

    The design for the RF systems for the APT (Accelerator Production of Tritium) proton linac will be presented. The linac produces a continuous beam power of 130 MW at 1300 MeV with the installed capability to produce up to a 170 MW beam at 1700 MeV. The linac is comprised of a 350 MHz RFQ to 7 MeV followed in sequence by a 700 MHz coupled-cavity drift tube linac, coupled-cavity linac, and superconducting (SC) linac to 1700 MeV. At the 1700 MeV, 100 mA level the linac requires 213 MW of continuous-wave (CW) RF power. This power will be supplied by klystrons with a nominal output power of 1.0 MW. 237 kystrons are required with all but three of these klystrons operating at 700 MHz. The klystron count includes redundancy provisions that will be described which allow the RF systems to meet an operational availability in excess of 95 percent. The approach to achieve this redundancy will be presented for both the normal conducting (NC) and SC accelerators. Because of the large amount of CW RF power required for the APT linac, efficiency is very important to minimize operating cost. Operation and the RF system design, including in-progress advanced technology developments which improve efficiency, will be discussed. RF system performance will also be predicted. Because of the simultaneous pressures to increase RF system reliability, reduce tunnel envelope, and minimize RF system cost, the design of the RF vacuum windows has become an important issue. The power from a klystron will be divided into four equal parts to minimize the stress on the RF vacuum windows. Even with this reduction, the RF power level at the window is at the upper boundary of the power levels employed at other CW accelerator facilities. The design of a 350 MHz, coaxial vacuum window will be presented as well as test results and high power conditioning profiles. The transmission of 950 kW, CW, power through this window has been demonstrated with only minimal high power conditioning.

  2. Demonstration of 5MW PAFC power plant

    SciTech Connect

    Usami, Yutaka; Takae, Toshio

    1996-12-31

    Phosphoric Acid Fuel Cell Technology Research Association, established in May 1991 by Japanese 10 electric power and 4 gas companies, started a new project in 1991 FY, with the object of PAFC realization and aiming the development of 5MW- class PAFC. power plant for urban energy center and 1 MW- class power plant for onsite use. This project is carried out as 6 years plan jointly with New Energy and Industrial Technology Development Organization. The targets of the project are to evaluate and resolve the development task, such as a high reliability, compactness and cost reduction throughout the engineering, manufacturing and field testing of PAFC power plants. PAC tests and power generating test operations of 5MW plant were completed in 1994. Conducting the 2 years continuous operations and studies since 1995, the plant operational performance, system control characteristics, waste heat recovery and environmental advantage will be demonstrated.

  3. Proton Therapy

    MedlinePlus

    ... effects of the treatment. top of page What equipment is used? Proton beam therapy uses special machines, ... tumor cells. top of page Who operates the equipment? With backgrounds in mechanical, electrical, software, hardware and ...

  4. 24 CFR 1.4 - Discrimination prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Discrimination prohibited. 1.4... DEVELOPMENT-EFFECTUATION OF TITLE VI OF THE CIVIL RIGHTS ACT OF 1964 § 1.4 Discrimination prohibited. (a... excluded from participation in, be denied the benefits of, or be otherwise subjected to...

  5. 24 CFR 1.4 - Discrimination prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Discrimination prohibited. 1.4... DEVELOPMENT-EFFECTUATION OF TITLE VI OF THE CIVIL RIGHTS ACT OF 1964 § 1.4 Discrimination prohibited. (a... excluded from participation in, be denied the benefits of, or be otherwise subjected to...

  6. 24 CFR 1.4 - Discrimination prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Discrimination prohibited. 1.4... DEVELOPMENT-EFFECTUATION OF TITLE VI OF THE CIVIL RIGHTS ACT OF 1964 § 1.4 Discrimination prohibited. (a... excluded from participation in, be denied the benefits of, or be otherwise subjected to...

  7. 24 CFR 1.4 - Discrimination prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Discrimination prohibited. 1.4... DEVELOPMENT-EFFECTUATION OF TITLE VI OF THE CIVIL RIGHTS ACT OF 1964 § 1.4 Discrimination prohibited. (a... excluded from participation in, be denied the benefits of, or be otherwise subjected to...

  8. 21 CFR 1.4 - Authority citations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... statute is the Federal Food, Drug, and Cosmetic Act, the Public Health Service Act, or the Fair Packaging... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Authority citations. 1.4 Section 1.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL GENERAL...

  9. 26 CFR 1.4-2 - Elections.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Elections. 1.4-2 Section 1.4-2 Internal Revenue....4-2 Elections. (a) Making of election. The election to pay the optional tax imposed under section 3... the standard deduction provided by section 141. (b) Election under section 3 and election of...

  10. 45 CFR 1206.1-4 - Suspension.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Suspension. 1206.1-4 Section 1206.1-4 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE GRANTS AND CONTRACTS-SUSPENSION AND TERMINATION AND DENIAL OF APPLICATION FOR REFUNDING Suspension and Termination of Assistance §...

  11. PCFB Repowering Project 80 MW plant description

    SciTech Connect

    Not Available

    1994-05-01

    This report documents the design of a 80 MW Pressurized Circulating Fluidized Bed (PCFB) boiler for the repowering of Unit 1 at the Des Moines Energy Center. Objective is to demonstrate that PCFB combined-cycle technology is cost effective and environmentally superior compared to traditional pulverized coal burning facilities.

  12. Intramolecular C-H···O hydrogen bonding in 1,4-dihydropyridine derivatives.

    PubMed

    Petrova, Marina; Muhamadejev, Ruslan; Vigante, Brigita; Cekavicus, Brigita; Plotniece, Aiva; Duburs, Gunars; Liepinsh, Edvards

    2011-09-19

    The diastereotopy of the methylene protons at positions 2 and 6 in 1,4-dihydropiridine derivatives with various substituents has been investigated. NMR spectroscopy and quantum chemistry calculations show that the CH···O intramolecular hydrogen bond is one of the factors amplifying the chemical shift differences in the 1H-NMR spectra.

  13. COMPACT PROTON INJECTOR AND FIRST ACCELERATOR SYSTEM TEST FOR COMPACT PROTON DIELECTRIC WALL CANCER THERAPY ACCELERATOR

    SciTech Connect

    Chen, Y; Guethlein, G; Caporaso, G; Sampayan, S; Blackfield, D; Cook, E; Falabella, S; Harris, J; Hawkins, S; Nelson, S; Poole, B; Richardson, R; Watson, J; Weir, J; Pearson, D

    2009-04-23

    A compact proton accelerator for cancer treatment is being developed by using the high-gradient dielectric insulator wall (DWA) technology [1-4]. We are testing all the essential DWA components, including a compact proton source, on the First Article System Test (FAST). The configuration and progress on the injector and FAST will be presented.

  14. Coordination chemistry of 1,4-bis-carboxymethylcyclam, H(2)(1,4-bcc).

    PubMed

    Tonei, Deborah M; Ware, David C; Brothers, Penelope J; Plieger, Paul G; Clark, George R

    2006-01-07

    Zinc metal reduction of the cobalt(III) complex [Co(1,4-bcc)](+) (1,4-bcc = 1,4-bis-carboxymethylcyclam) produces the corresponding cobalt(II) complex which crystallises as the coordination polymer {[Co(1,4-bcc)]ZnCl(2)}(n). A method has been developed for removal of the cobalt(III) ion from [Co(1,4-bcc)](+) and isolation of the free ligand as its hydrochloride salt, H(2)(1,4-bcc).4HCl. This has been used for the preparation of new metal complexes, and the syntheses and characterisation of the copper(ii), nickel(ii), zinc(ii) and chromium(iii) complexes containing the 1,4-bcc ligand are described. X-Ray crystal structures of {[Co(1,4-bcc)]ZnCl(2)}(n).2.5H(2)O, {[Cu(1,4-bcc)]CuCl(2)}(n).0.25MeOH.H(2)O and [Cu(1,4-bcc)H]ClO(4) show the complexes to have the trans(O) geometry of the 1,4-bcc ligand, while the structure of [Cr(1,4-bcc)H(0.5)](ClO(4))(1.5).EtOH exhibits the cis(O) configuration.

  15. Fermilab's Proton Accelerator Complex : World Record Performance and Upgrade Plans

    NASA Astrophysics Data System (ADS)

    Shiltsev, Vladimir

    2017-01-01

    The flagship of Fermilab's long term research program is the Deep Underground Neutrino Experiment (DUNE), located Sanford Underground Research Facility (SURF) in Lead, South Dakota, which will study neutrino oscillations with a baseline of 1300 km. The neutrinos will be produced in the Long Baseline Neutrino Facility (LBNF), a proposed new beam line from Fermilab's Main Injector. The physics goals of the DUNE require a proton beam with a power of some 2.4 MW at 120 GeV, which is roughly four times the current maximum power. Here I discuss current performance of the Fermilab proton accelerator complex, our plans for construction of the SRF proton linac as key part of the Proton Improvement Plan-II (PIP-II), outline the main challenges toward multi-MW beam power operation of the Fermilab accelerator complex and the staged plan to achieve the required performance over the next 15 years.

  16. Proton Therapy

    MedlinePlus

    ... Liver Breast Esophagus Rectum Skull base sarcomas Pediatric brain tumors Head and neck - see the Head and Neck Cancer page Eye ... Intensity-Modulated Radiation Therapy (IMRT) Brain Tumor Treatment Brain Tumors Prostate Cancer Lung Cancer ... related to Proton Therapy Videos related ...

  17. Proton Radiobiology

    PubMed Central

    Tommasino, Francesco; Durante, Marco

    2015-01-01

    In addition to the physical advantages (Bragg peak), the use of charged particles in cancer therapy can be associated with distinct biological effects compared to X-rays. While heavy ions (densely ionizing radiation) are known to have an energy- and charge-dependent increased Relative Biological Effectiveness (RBE), protons should not be very different from sparsely ionizing photons. A slightly increased biological effectiveness is taken into account in proton treatment planning by assuming a fixed RBE of 1.1 for the whole radiation field. However, data emerging from recent studies suggest that, for several end points of clinical relevance, the biological response is differentially modulated by protons compared to photons. In parallel, research in the field of medical physics highlighted how variations in RBE that are currently neglected might actually result in deposition of significant doses in healthy organs. This seems to be relevant in particular for normal tissues in the entrance region and for organs at risk close behind the tumor. All these aspects will be considered and discussed in this review, highlighting how a re-discussion of the role of a variable RBE in proton therapy might be well-timed. PMID:25686476

  18. Subducted sediment thickness and Mw 9 earthquakes

    NASA Astrophysics Data System (ADS)

    Seno, Tetsuzo

    2017-01-01

    I measure the thickness of subducted sediment (Δss) beneath the décollement in the fore-arc wedge and show that the average value of Δss over a subduction zone segment (Δss>¯) is greater than 1.3 km in segments where Mw ≥ 9 earthquakes have occurred and less than 1.2 km in segments without such large earthquakes. In a previous study, I showed that the stress drop (Δσ) of large earthquakes (Mw ≥ 7) averaged over a subduction zone segment (Δσ>¯) is larger in segments where Mw ≥ 9 earthquakes have occurred than in segments without such an event. It has also been shown that Δσ>¯ is linearly related to 1 - λ (λ = the pore fluid pressure ratio in the interplate megathrust). In this study, I revise the previous estimates of Δσ>¯ and λ and show that there is a positive correlation between Δss>¯, Δσ>¯, and 1 - λ. I present a model that relates Δss to 1 - λ based on the porous flow of H2O in the subducted sediments, which gives a theoretical basis for the correlation between Δss>¯ and Δσ>¯. The combination of these parameters thus provides a better indicator for identifying segments where Mw ≥ 9 earthquakes may occur. Based on this, I propose that the tectonic environments where such huge events are likely to occur are (1) near collision zones, (2) near subduction of spreading centers, and (3) erosive margins with compressional fore arcs. Near the Japanese islands, SE Hokkaido is prone to such an event, but the Nankai Trough is not.

  19. 5MW Raft River Facility Experience

    SciTech Connect

    Whitbeck, J.F.

    1980-12-01

    Located in Northern California In Lake and Sonoma Counties about 90 miles north of San Francisco, Pacific Gas and Electric Company's (PG and E's) The Geysers Power Plant, which has at present fourteen units in service with a net generating capacity of 798MW, is the largest geothermal development in the world. Eight additional PG and E units now in construction, design, and planning will add 720MW of additional capacity by 1986. Figure 1 shows the location of this project and the locations of the existing and future units. This paper discusses evolution of Geysers Unit 18 through resource and project planning, licensing, design, and what is expected during construction, and startup. While many of the experiences are unique to The Geysers units, some could be applicable to other geothermal developments. This unit is one of a series of 110MW units of standardized design which are being developed to reduce the cost and improve schedules. Construction has just commenced, and it is expected to be in commercial operation in October 1982.

  20. Biodegradation of 1,4-Dioxane

    DTIC Science & Technology

    2007-08-01

    Pseudonocardia sp. strain K1 was used to hydrolyze diglycolic acid, the free radical generator phenazine methosulfate was included in the assay, as reported... phenazine methosulfate is not a physiologically relevant compound and can not be involved in 1,4-dioxane mineralization in vivo. III. D. Discussion of

  1. Proton maser

    NASA Astrophysics Data System (ADS)

    Ensley, D. L.

    1988-01-01

    New calculations are reported which confirm the ability of an a priori random, initial-phase proton beam to drive a simple, single-stage microwave cavity maser or transit-time oscillator (TTO) to saturation conversion efficiencies of about 11 percent. The required initial TE(011) mode field can be provided from beam ramp-up bandwidth of excitation to a low level from an external source. A saturation field of 45 tesla and output power of 0.2 TW are calculated using an electron insulation field of 10 tesla and a 3 MeV, 400 Ka/sq cm beam. Results are compared to those for an electron beam of the same energy and geometry, and it is shown that proton beams potentially can provide a three order of magnitude increase in overall microwave power production density over that obtainable from electron beam TTOs.

  2. The 2 MW Santa Clara Project

    NASA Astrophysics Data System (ADS)

    Eichenberger, Paul H.

    The City of Santa Clara, CA, USA, has hosted the world's first field demonstration of a molten carbonate fuel cell power plant. This US$46 million, 2 MW generator was a joint effort of five US utilities, the federal government, and two US research organizations. The demonstration used sixteen 125 kW stacks placed in four modules. The balance of plant (BOP) is the equipment that prepares and supplies the fuel to the stacks and converts the d.c. current to a.c. BOP construction started in April 1994, and was completed in June 1995. The BOP configuration allowed testing and development before installation of the four modules. The final full-temperature test was completed in February 1996. The four fuel cell modules were installed and cured, and power delivery began in April 1996. The plant operated for approximately 720 h at design output before electrical anomalies occurred and the plant was shut down for repairs. The plant restarted in August, but it soon became obvious that other problems had been caused by the electrical anomalies. The plant shut down and was reconfigured to a 1 MW plant. The restarted plant was ramped to 1 MW, but additional problems began to occur and the plant demonstration ended. The plant produced 2500 MWh, and operated at 1000°F, or higher, for over 5290 h. The plant set operational records, and demonstrated multistack, automatic control, and stable-field operation. Power quality met all standards with no measurable NOx or SOx output. The plant isolated itself from the grid during two major California, USA grid outages. The plant also experienced a shutdown of the automatic control system, and placed itself on hot standby using the mechanical field systems. The plant then restarted without incident.

  3. A 75 MW S-Band Klystron

    SciTech Connect

    Ferguson, Patrick; Read, Michael; Ives, Robert Lawrence; Marsden, David

    2013-12-16

    This program performed computational and preliminary mechanical design for a klystron producing 75 MW at 2.856 GHz using periodic permanent magnet (PPM) focusing. The performance specifications achieved were those for the Matter-Radiation Interactions in the Extremes (MaRIE) project at Los Alamos National Laboratory. The klystron is designed to provide 10 microsecond pulses at 60 Hz with 56 dB gain. The PPM-Focusing eliminates requirements for solenoids and their associated power supplies, cooling systems, interlocks, control and diagnostic instrumentation, and maintenance. The represents a significant in both acquisition and operating costs. It also increases reliability by eliminating many potential failure modes.

  4. MW-Class Electric Propulsion System Designs

    NASA Technical Reports Server (NTRS)

    LaPointe, Michael R.; Oleson, Steven; Pencil, Eric; Mercer, Carolyn; Distefano, Salvador

    2011-01-01

    Electric propulsion systems are well developed and have been in commercial use for several years. Ion and Hall thrusters have propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system, while higher power systems are being considered to support even more demanding future space science and exploration missions. Such missions may include orbit raising and station-keeping for large platforms, robotic and human missions to near earth asteroids, cargo transport for sustained lunar or Mars exploration, and at very high-power, fast piloted missions to Mars and the outer planets. The Advanced In-Space Propulsion Project, High Efficiency Space Power Systems Project, and High Power Electric Propulsion Demonstration Project were established within the NASA Exploration Technology Development and Demonstration Program to develop and advance the fundamental technologies required for these long-range, future exploration missions. Under the auspices of the High Efficiency Space Power Systems Project, and supported by the Advanced In-Space Propulsion and High Power Electric Propulsion Projects, the COMPASS design team at the NASA Glenn Research Center performed multiple parametric design analyses to determine solar and nuclear electric power technology requirements for representative 300-kW class and pulsed and steady-state MW-class electric propulsion systems. This paper describes the results of the MW-class electric power and propulsion design analysis. Starting with the representative MW-class vehicle configurations, and using design reference missions bounded by launch dates, several power system technology improvements were introduced into the parametric COMPASS simulations to determine the potential system level benefits such technologies might provide. Those technologies providing quantitative system level benefits were then assessed for technical feasibility, cost, and time to develop. Key assumptions and primary

  5. 7. Photocopy of photographca. 1927 (2 1/4 X 2 1/4' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Photocopy of photograph--ca. 1927 (2 1/4 X 2 1/4' negative) DETAIL SHOWING ADAPTATION THAT ALLOWED USE OF UPPER END OF ORIGINAL FLUME AND LOWER END JUST RECONSTRUCTED - Power Flume No. 1, Tacoma, La Plata County, CO

  6. THERMAL SHOCK INDUCED BY A 24 GEV PROTON BEAM IN THE TEST WINDOWS OF THE MUON COLLIDER EXPERIMENT E951 - TEST RESULTS AND THEORETICAL PREDICTIONS.

    SciTech Connect

    SIMOS,N.; KIRK,H.; FINFROCK,C.; PRIGL,R.; BROWN,K.; KAHN,S.; LUDEWIG,H.; MCDONALDK.; CATES,M.; TSAI,J.; BESHEARS,D.; RIEMER,B.

    2001-11-11

    The need for intense muon beams for muon colliders and neutrino factories has lead to a concept of a high performance target station in which a 1-4 MW proton beam of 6-24 GeV impinges on a target inside a high field solenoid channel. While novel technical issues exist regarding the survivability of the target itself, the need to pass the tightly focused proton beam through beam windows poses additional concerns. In this paper, issues associated with the interaction of a proton beam with window structures designed for the muon targetry experiment E951 at BNL are explored. Specifically, a 24 GeV proton beam up to 16 x 10{sup 12} per pulse and a pulse length of approximately 100 ns is expected to be tightly focused (to 0.5 mm rms one sigma radius) on an experimental target. Such beam will induce very high thermal, quasi-static and shock stresses in the window structure that exceed the strength of most common materials. In this effort, a detailed assessment of the thermal/shock response of beam windows is attempted with a goal of identifying the best window material candidate. Further, experimental strain results and comparison with the predicted values are presented and discussed.

  7. High-Intensity Proton Accelerator

    SciTech Connect

    Jay L. Hirshfield

    2011-12-27

    Analysis is presented for an eight-cavity proton cyclotron accelerator that could have advantages as compared with other accelerators because of its potentially high acceleration gradient. The high gradient is possible since protons orbit in a sequence of TE111 rotating mode cavities of equally diminishing frequencies with path lengths during acceleration that greatly exceed the cavity lengths. As the cavities operate at sequential harmonics of a basic repetition frequency, phase synchronism can be maintained over a relatively wide injection phase window without undue beam emittance growth. It is shown that use of radial vanes can allow cavity designs with significantly smaller radii, as compared with simple cylindrical cavities. Preliminary beam transport studies show that acceptable extraction and focusing of a proton beam after cyclic motion in this accelerator should be possible. Progress is also reported on design and tests of a four-cavity electron counterpart accelerator for experiments to study effects on beam quality arising from variations injection phase window width. This device is powered by four 500-MW pulsed amplifiers at 1500, 1800, 2100, and 2400 MHz that provide phase synchronous outputs, since they are driven from a with harmonics derived from a phase-locked 300 MHz source.

  8. 110 GHz, 1 MW Gyrotron Design Upgrades

    NASA Astrophysics Data System (ADS)

    Cauffman, Steve; Felch, Kevin; Borchard, Philipp; Cahalan, Pat; Chu, Sam; Dubrule, Craig

    1999-11-01

    Communications and Power Industries has incorporated a number of design changes into its most recent series of 110 GHz 1 MW gyrotrons, for use in ECH and ECCD experiments on the DIII-D tokamak. Two development gyrotrons previously installed at DIII-D used a modulating-anode electron gun design and output windows consisting of double-disk face-cooled sapphire on one system and an edge-cooled CVD diamond disk on the other. Three new systems presently in fabrication and test employ (a) a single-anode electron gun to avoid excitation of spurious modes during turn-on and turn-off and to simplify power supply requirements, (b) a modified TE_22,6 cavity to reduce competition from neighboring modes, (c) a two inch aperture edge-cooled CVD diamond window to allow transmission of a 1 MW Gaussian output beam, (d) a superconducting magnet system with a cryo-cooler to reduce liquid helium consumption, and (e) a number of internal and external plumbing simplifications to make cooling system connections more straightforward. Initial test results, if available, will be presented.

  9. Controlling the binding of dihydrogen using ruthenium complexes containing N-mono-functionalised 1,4,7-triazacyclononane ligand systems.

    PubMed

    Gott, Andrew L; McGowan, Patrick C; Podesta, Thomas J

    2008-07-28

    Pendant arm macrocycles derived from 1,4,7-triazacyclononane were reacted with RuHCl(CO)(PPh(3))(3) and RuHCl(PPh(3))(3) to yield air-stable cationic ruthenium hydrides that were characterised by a variety of techniques, including X-ray crystallography. Protonation of the metal hydride complexes with a proton source yielded eta(2)-dihydrogen complexes. The lifetime of the dihydrogen ligand was effected by a judicious choice of ancillary ligands.

  10. Proton scaling

    SciTech Connect

    Canavan, Gregory H

    2009-01-01

    This note presents analytic estimates of the performance of proton beams in remote surveillance for nuclear materials. The analysis partitions the analysis into the eight steps used by a companion note: (1) Air scattering, (2) Neutron production in the ship and cargo, (3) Target detection probability, (4) Signal produced by target, (5) Attenuation of signal by ship and cargo, (6) Attenuation of signal by air, (7) Geometric dilution, and (8) Detector Efficiency. The above analyses indicate that the dominant air scattering and loss mechanisms for particle remote sensing are calculable with reliable and accepted tools. They make it clear that the conversion of proton beams into neutron sources rapidly goes to completion in all but thinnest targets, which means that proton interrogation is for all purposes executed by neutrons. Diffusion models and limiting approximations to them are simple and credible - apart from uncertainty over the cross sections to be used in them - and uncertainty over the structure of the vessels investigated. Multiplication is essentially unknown, in part because it depends on the details of the target and its shielding, which are unlikely to be known in advance. Attenuation of neutron fluxes on the way out are more complicated due to geometry, the spectrum of fission neutrons, and the details of their slowing down during egress. The attenuation by air is large but less uncertain. Detectors and technology are better known. The overall convolution of these effects lead to large but arguably tolerable levels of attenuation of input beams and output signals. That is particularly the case for small, mobile sensors, which can more than compensate for size with proximity to operate reliably while remaining below flux limits. Overall, the estimates used here appear to be of adequate accuracy for decisions. That assessment is strengthened by their agreement with companion calculations.

  11. SAS 3 observations of GX 1 + 4

    NASA Technical Reports Server (NTRS)

    Doty, J. P.; Lewin, W. H. G.; Hoffman, J. A.

    1981-01-01

    GX 1 + 4 is one of the brightest celestial sources of high-energy X-rays. It is a pulsar with a period of approximately 2 min (perhaps a multiple of 2 min), decreasing at a variable rate which, since 1971, has averaged approximately 2% per year, but which can be larger than 5% per year. This is the largest rate of decrease observed for any pulsar. The rate of decrease appears to be correlated with the luminosity, in support of the idea that the period decrease is produced by accretion torques acting upon a neutron star. No evidence is seen for a Doppler shift due to motion of the pulsar in a binary orbit; this is consistent with the results of optical observations which suggest that any orbital period is fairly long (months to years). The spectrum of GX 1 + 4 is measured as a function of pulse phase, as well as the phase-averaged total spectrum, and the average spectrum of the pulses alone. The shape of the average pulsed spectrum suggests that the pulsations may be produced by 'hot spots' which are a few hundred meters in extent, with temperatures of approximately 10 to the 8th K (kT being approximately equal to 8 keV).

  12. High-K,t1/2=1.4(1) ms, isomeric state in Lr255

    NASA Astrophysics Data System (ADS)

    Hauschild, K.; Lopez-Martens, A.; Yeremin, A. V.; Dorvaux, O.; Antalic, S.; Belozerov, A. V.; Briançon, Ch.; Chelnokov, M. L.; Chepigin, V. I.; Curien, D.; Gall, B.; Görgen, A.; Gorshkov, V. A.; Guttormsen, M.; Hanappe, F.; Kabachenko, A. P.; Khalfallah, F.; Larsen, A. C.; Malyshev, O. N.; Minkova, A.; Popeko, A. G.; Rousseau, M.; Rowley, N.; Saro, S.; Shutov, A. V.; Siem, S.; Stuttgè, L.; Svirikhin, A. I.; Syed, N. U. H.; Theisen, Ch.; Venhart, M.

    2008-08-01

    An isomeric state in Lr255 with a half-life of t1/2=1.4(1) ms and Ex>720-keV has been observed for the first time using the GABRIELA setup at the focal plane of the VASSILISSA separator. Based on its K-forbiddeness, the configuration of the state is most probably formed by coupling the valence proton to a two quasiparticle neutron excitation. Possible three quasiparticle configurations are discussed.

  13. Analysis of the Rotational Structure in the High-Resolution Infrared Spectra of cis,cis- and trans,trans-1,4-DIFLUOROBUTADIENE-1-d_{1} and trans,trans-1,4-DIFLUOROBUTADIENE-1,4-d_{2}

    NASA Astrophysics Data System (ADS)

    Craig, Norman C.; Chen, Yihui; Lu, Yuhua; Neese, Christopher F.; Nemchick, Deacon J.; Blake, Thomas A.

    2013-06-01

    Samples of cis,cis- and trans,trans-1,4-difluorobutadiene-1-d_{1} (DFBD) and trans,trans-DFBD-1,4-d_{2} have been synthesized and investigated with high-resolution (0.0015 cm^{-1}) infrared spectroscopy. For the first two species the rotational structure in more than one band has been analyzed. For the 1,4-d_{2} species the spectrum of only one C-type band was available in an isotopic mixture. Ground state rotational constants are reported for all three molecules. It is proposed that quartic centrifugal distortion constants computed with a B3LYP/cc-pVTZ model can be used to assess the quality of observed rotational constants. The favorable comparison of predicted and observed ground state rotational constants for all four ^{13}C species of cis,trans-DFBD, which is MW active, demonstrates that the ground state rotational constants for the ^{13}C species of the cis,cis and trans,trans isomers can be successfully predicted with high accuracy. Rotational constants for a full set of isotopologues will be used to determine accurate semiexperimental equilibrium structures of the cis,cis and trans,trans species of DFBD. N. C. Craig, C. M. Oertel, D. C. Oertel, M. J. Tubergen, R. J. Lavrich, A. M Chaka J. Phys. Chem. A 106, 4230-4235 (2002).

  14. Proton radiography to improve proton therapy treatment

    NASA Astrophysics Data System (ADS)

    Takatsu, J.; van der Graaf, E. R.; Van Goethem, M.-J.; van Beuzekom, M.; Klaver, T.; Visser, J.; Brandenburg, S.; Biegun, A. K.

    2016-01-01

    The quality of cancer treatment with protons critically depends on an accurate prediction of the proton stopping powers for the tissues traversed by the protons. Today, treatment planning in proton radiotherapy is based on stopping power calculations from densities of X-ray Computed Tomography (CT) images. This causes systematic uncertainties in the calculated proton range in a patient of typically 3-4%, but can become even 10% in bone regions [1,2,3,4,5,6,7,8]. This may lead to no dose in parts of the tumor and too high dose in healthy tissues [1]. A direct measurement of proton stopping powers with high-energy protons will allow reducing these uncertainties and will improve the quality of the treatment. Several studies have shown that a sufficiently accurate radiograph can be obtained by tracking individual protons traversing a phantom (patient) [4,6,10]. Our studies benefit from the gas-filled time projection chambers based on GridPix technology [2], developed at Nikhef, capable of tracking a single proton. A BaF2 crystal measuring the residual energy of protons was used. Proton radiographs of phantom consisting of different tissue-like materials were measured with a 30×30 mm2 150 MeV proton beam. Measurements were simulated with the Geant4 toolkit.First experimental and simulated energy radiographs are in very good agreement [3]. In this paper we focus on simulation studies of the proton scattering angle as it affects the position resolution of the proton energy loss radiograph. By selecting protons with a small scattering angle, the image quality can be improved significantly.

  15. Development of a 5 MW reference gearbox for offshore wind turbines: 5 MW reference gearbox

    SciTech Connect

    Nejad, Amir Rasekhi; Guo, Yi; Gao, Zhen; Moan, Torgeir

    2015-07-27

    This paper presents detailed descriptions, modeling parameters and technical data of a 5MW high-speed gearbox developed for the National Renewable Energy Laboratory offshore 5MW baseline wind turbine. The main aim of this paper is to support the concept studies and research for large offshore wind turbines by providing a baseline gearbox model with detailed modeling parameters. This baseline gearbox follows the most conventional design types of those used in wind turbines. It is based on the four-point supports: two main bearings and two torque arms. The gearbox consists of three stages: two planetary and one parallel stage gears. The gear ratios among the stages are calculated in a way to obtain the minimum gearbox weight. The gearbox components are designed and selected based on the offshore wind turbine design codes and validated by comparison to the data available from large offshore wind turbine prototypes. All parameters required to establish the dynamic model of the gearbox are then provided. Moreover, a maintenance map indicating components with high to low probability of failure is shown. The 5 MW reference gearbox can be used as a baseline for research on wind turbine gearboxes and comparison studies. It can also be employed in global analysis tools to represent a more realistic model of a gearbox in a coupled analysis.

  16. 76 FR 7703 - 1,4-Benzenedicarboxylic Acid, Dimethyl Ester, Polymer With 1,4-Butanediol, Adipic Acid, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... AGENCY 40 CFR Part 180 1,4-Benzenedicarboxylic Acid, Dimethyl Ester, Polymer With 1,4- Butanediol, Adipic..., polymer with 1,4-butanediol, adipic acid, and hexamethylene diisocyanate (CAS Reg. No. 55231-08-8... residues of 1,4-benzenedicarboxylic acid, dimethyl ester, polymer with 1,4-butanediol, adipic acid,...

  17. Synchrotron based proton drivers

    SciTech Connect

    Weiren Chou

    2002-09-19

    Proton drivers are the proton sources that produce intense short proton bunches. They have a wide range of applications. This paper discusses the proton drivers based on high-intensity proton synchrotrons. It gives a review of the high-intensity proton sources over the world and a brief report on recent developments in this field in the U.S. high-energy physics (HEP) community. The Fermilab Proton Driver is used as a case study for a number of challenging technical design issues.

  18. Proton Therapy - Accelerating Protons to Save Lives

    SciTech Connect

    Keppel, Cynthia

    2011-10-25

    In 1946, physicist Robert Wilson first suggested that protons could be used as a form of radiation therapy in the treatment of cancer because of the sharp drop-off that occurs on the distal edge of the radiation dose. Research soon confirmed that high-energy protons were particularly suitable for treating tumors near critical structures, such as the heart and spinal column. The precision with which protons can be delivered means that more radiation can be deposited into the tumor while the surrounding healthy tissue receives substantially less or, in some cases, no radiation. Since these times, particle accelerators have continuously been used in cancer therapy and today new facilities specifically designed for proton therapy are being built in many countries. Proton therapy has been hailed as a revolutionary cancer treatment, with higher cure rates and fewer side effects than traditional X-ray photon radiation therapy. Proton therapy is the modality of choice for treating certain small tumors of the eye, head or neck. Because it exposes less of the tissue surrounding a tumor to the dosage, proton therapy lowers the risk of secondary cancers later in life - especially important for young children. To date, over 80,000 patients worldwide have been treated with protons. Currently, there are nine proton radiation therapy facilities operating in the United States, one at the Hampton University Proton Therapy Institute. An overview of the treatment technology and this new center will be presented.

  19. Design, Synthesis, and Evaluation of 1,4,7,10-Tetraazacyclododecane-1,4,7-triacetic Acid-Derived, Redox-Sensitive Contrast Agents for Magnetic Resonance Imaging

    PubMed Central

    Raghunand, Natarajan; Guntle, Gerald P.; Gokhale, Vijay; Nichol, Gary S.; Mash, Eugene A.; Jagadish, Bhumasamudram

    2010-01-01

    The design and synthesis of three 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) derivatives bearing linkers with terminal thiol groups and a preliminary evaluation of their potential for use in assembling redox-sensitive Magnetic Resonance Imaging (MRI) contrast agents are reported. The linkers were selected based on computational docking with a crystal structure of human serum albumin (HSA). Gd(III)-DO3A and Eu(III)-DO3A complexes were synthesized, and the structure of one complex was established by X-ray crystallographic analysis. The binding to HSA of a Gd(III)-DO3A complex bearing a thiol-terminated 3,6-dioxanonyl chain was competitively inhibited by homocysteine and by the corresponding Eu chelate. Binding to HSA was abolished when the terminal thiol group of this complex was absent. The longitudinal water-proton relaxivities (r1) of the three Gd(III)-DO3A complexes and of two Gd(III)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) complexes were measured in saline at 7 Tesla. The DO3A complexes exhibited smaller r1 values, in both bound and free states, than the DOTA complexes. PMID:20722424

  20. Target designs for the Brookhaven National Laboratory 5-MW pulsed spallation neutron source

    SciTech Connect

    Ludewig, H.; Todosow, M.; Powell, J.R.

    1996-03-01

    A feasibility study of a compact high power density target for a spallation neutron source was under-taken. The target arrangement consists primarily of heavy metal, with appropriate cooling passages. A high intensity proton beam of intermediate energy is directed at the target, where it interacts with the heavy metal nuclei. The subsequent spallation reactions produce several neutrons per proton resulting in an intense neutron source. The proton beam is assumed to havean energy of 5 MW, and to be cyclic with a repetition rate of 10Hz and 50Hz. The study was divided into two broad sections. First, an analysis of preliminary target designs was undertaken to ensure the overall feasibility of the concepts involved in the design and eventual construction of such a high power density target. Second, two proposed target designs, based on the first set of analyses, are investigated in more detail. Special care is taken to ensure that the neutron fluxes in the moderator are at the desired level no material compatibility problems exist,and the target is able to operate in a reliable and safe manner. Several target materials, coolant types, and target arrangements are investigated in the first section. The second section concentrates on a single target material and geometric arrangement. However, several structural material choices continue to be investigated with the aim of minimizing the effects of structural heating, and associated thermally induced stresses. In the final section the conclusions of this preliminary study are summarized.

  1. First acceleration of a proton beam in a side coupled drift tube linac

    NASA Astrophysics Data System (ADS)

    Ronsivalle, C.; Picardi, L.; Ampollini, A.; Bazzano, G.; Marracino, F.; Nenzi, P.; Snels, C.; Surrenti, V.; Vadrucci, M.; Ambrosini, F.

    2015-07-01

    We report the first experiment aimed at the demonstration of low-energy protons acceleration by a high-efficiency S-band RF linear accelerator. The proton beam has been accelerated from 7 to 11.6 MeV by a 1 meter long SCDTL (Side Coupled Drift Tube Linac) module powered with 1.3 MW. The experiment has been done in the framework of the Italian TOP-IMPLART (Oncological Therapy with Protons-Intensity Modulated Proton Therapy Linear Accelerator for Radio-Therapy) project devoted to the realization of a proton therapy centre based on a proton linear accelerator for intensity modulated cancer treatments to be installed at IRE-IFO, the largest oncological hospital in Rome. It is the first proton therapy facility employing a full linear accelerator scheme based on high-frequency technology.

  2. Economic Benefits, Carbon Dioxide (CO2) Emissions Reductions, and Water Conservation Benefits from 1,000 Megawatts (MW) of New Wind Power in Massachusetts (Fact Sheet)

    SciTech Connect

    Lantz, E.; Tegen, S.

    2009-03-01

    The U.S. Department of Energy?s Wind Powering America Program is committed to educating state-level policymakers and other stakeholders about the economic, CO2 emissions, and water conservation impacts of wind power. This analysis highlights the expected impacts of 1000 MW of wind power in Massachusetts. Although construction and operation of 1000 MW of wind power is a significant effort, seven states have already reached the 1000-MW mark. We forecast the cumulative economic benefits from 1000 MW of development in Massachusetts to be $1.4 billion, annual CO2 reductions are estimated at 2.6 million tons, and annual water savings are 1,293 million gallons.

  3. Construction, completion, and testing of replacement monitoring wells MW 3-2, MW 6-2, MW 7-2, and MW 11-2, Mountain Home Air Force Base, Idaho, February through April 2000

    USGS Publications Warehouse

    Parliman, D.J.

    2000-01-01

    In February and March 2000, the U.S. Geological Survey Western Regional Research Drilling Operation constructed replacement monitoring wells MW 3–2, MW 6–2, MW 7–2, and MW 11–2 as part of a regional ground-water monitor- ing network for the Mountain Home Air Force Base, Elmore County, Idaho. Total well depths ranged from 435.5 to 456.5 feet, and initial depth-to-water measurements ranged from about 350 to 375 feet below land surface. After completion, wells were pumped and onsite measurements were made of water temperature, specific conductance, pH, and dissolved oxygen. At each well, natural gamma, spontaneous potential, resistivity, caliper, and temperature logs were obtained from instruments placed in open boreholes. A three- dimensional borehole flow analysis was completed for MW 3–2 and MW 11–2, and a video log was obtained for MW 11–2 to annotate lithology and note wet zones in the borehole above saturated rock.

  4. Description of an 8 MW reference wind turbine

    NASA Astrophysics Data System (ADS)

    Desmond, Cian; Murphy, Jimmy; Blonk, Lindert; Haans, Wouter

    2016-09-01

    An 8 MW wind turbine is described in terms of mass distribution, dimensions, power curve, thrust curve, maximum design load and tower configuration. This turbine has been described as part of the EU FP7 project LEANWIND in order to facilitate research into logistics and naval architecture efficiencies for future offshore wind installations. The design of this 8 MW reference wind turbine has been checked and validated by the design consultancy DNV-GL. This turbine description is intended to bridge the gap between the NREL 5 MW and DTU 10 reference turbines and thus contribute to the standardisation of research and development activities in the offshore wind energy industry.

  5. Catalytic enantioselective protonation of enol trifluoroacetates by means of hydrogenocarbonates and cinchona alkaloids.

    PubMed

    Claraz, Aurélie; Leroy, Jérôme; Oudeyer, Sylvain; Levacher, Vincent

    2011-08-05

    Herein is disclosed an efficient catalytic enantioselective protonation of enol acetates by means of a readily implementable transition-metal-free chemical process. By making use of simple hygrogenocarbonates as the proton source and hydroquinine anthraquinone-1,4-diyl diether as the chiral proton shuttle, a series of cyclic enol trifluoroacetates are protonated under mild conditions to yield the corresponding ketones in up to 93% ee.

  6. Characterizing the proton loading site in cytochrome c oxidase.

    PubMed

    Lu, Jianxun; Gunner, M R

    2014-08-26

    Cytochrome c oxidase (CcO) uses the energy released by reduction of O2 to H2O to drive eight charges from the high pH to low pH side of the membrane, increasing the electrochemical gradient. Four electrons and protons are used for chemistry, while four more protons are pumped. Proton pumping requires that residues on a pathway change proton affinity through the reaction cycle to load and then release protons. The protonation states of all residues in CcO are determined in MultiConformational Continuum Electrostatics simulations with the protonation and redox states of heme a, a3, Cu(B), Y288, and E286 used to define the catalytic cycle. One proton is found to be loaded and released from residues identified as the proton loading site (PLS) on the P-side of the protein in each of the four CcO redox states. Thus, the same proton pumping mechanism can be used each time CcO is reduced. Calculations with structures of Rhodobacter sphaeroides, Paracoccus denitrificans, and bovine CcO derived by crystallography and molecular dynamics show the PLS functions similarly in different CcO species. The PLS is a cluster rather than a single residue, as different structures show 1-4 residues load and release protons. However, the proton affinity of the heme a3 propionic acids primarily determines the number of protons loaded into the PLS; if their proton affinity is too low, less than one proton is loaded.

  7. Elastic proton-proton scattering at RHIC

    SciTech Connect

    Yip, K.

    2011-09-03

    Here we describe elastic proton+proton (p+p) scattering measurements at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run. We present preliminary results of single and double spin asymmetries.

  8. Proton pump inhibitors

    MedlinePlus

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This ...

  9. What's In a Proton?

    ScienceCinema

    Brookhaven Lab

    2016-07-12

    Physicist Peter Steinberg explains that fundamental particles like protons are themselves made up of still smaller particles called quarks. He discusses how new particles are produced when quarks are liberated from protons...a process that can be observed

  10. What's In a Proton?

    SciTech Connect

    Brookhaven Lab

    2009-07-08

    Physicist Peter Steinberg explains that fundamental particles like protons are themselves made up of still smaller particles called quarks. He discusses how new particles are produced when quarks are liberated from protons...a process that can be observed

  11. High-power targets: experience and R&D for 2 MW

    SciTech Connect

    Hurh, P.; Caretta, O.; Davenne, T.; Densham, C.; Loveridge, P.; Simos, N.; /Brookhaven

    2011-03-01

    High-power particle production targets are crucial elements of future neutrino and other rare particle beams. Fermilab plans to produce a beam of neutrinos (LBNE) with a 2.3 MW proton beam (Project X). Any solid target is unlikely to survive for an extended period in such an environment - many materials would not survive a single beam pulse. We are using our experience with previous neutrino and antiproton production targets, along with a new series of R&D tests, to design a target that has adequate survivability for this beamline. The issues considered are thermal shock (stress waves), heat removal, radiation damage, radiation accelerated corrosion effects, physics/geometry optimization and residual radiation.

  12. Inelastic scattering research at a 1 MW long pulse spallation neutron source

    SciTech Connect

    Carlile, C.J.

    1995-12-31

    The brief was, with respect to the LPSS bench mark design supplied (60 Hz, 1 MW, Imsec proton pulse, with a split, non-fissile target and 4 moderators in a flux trap geometry design), to identify a set of instruments, and to assess their performance with respect to existing spectrometers on other sources. Any modifications to the existing instruments which would make them more effective on the bench-mark source, or conversely, any modifications to the source bench-mark required by the proposed instruments were to be identified, as were any uncertainties in the estimated performances, or any R & D needed to make the proposed instruments viable. Any new instrument concepts specifically matched to the long pulse itself were to be identified and assessed. This process was to result in an indicative list of instruments for the source. A figure of around 10 spectrometers was to be aimed for.

  13. Proton: the particle.

    PubMed

    Suit, Herman

    2013-11-01

    The purpose of this article is to review briefly the nature of protons: creation at the Big Bang, abundance, physical characteristics, internal components, and life span. Several particle discoveries by proton as the experimental tool are considered. Protons play important roles in science, medicine, and industry. This article was prompted by my experience in the curative treatment of cancer patients by protons and my interest in the nature of protons as particles. The latter has been stimulated by many discussions with particle physicists and reading related books and journals. Protons in our universe number ≈10(80). Protons were created at 10(-6) -1 second after the Big Bang at ≈1.37 × 10(10) years beforethe present. Proton life span has been experimentally determined to be ≥10(34) years; that is, the age of the universe is 10(-24)th of the minimum life span of a proton. The abundance of the elements is hydrogen, ≈74%; helium, ≈24%; and heavier atoms, ≈2%. Accordingly, protons are the dominant baryonic subatomic particle in the universe because ≈87% are protons. They are in each atom in our universe and thus involved in virtually every activity of matter in the visible universe, including life on our planet. Protons were discovered in 1919. In 1968, they were determined to be composed of even smaller particles, principally quarks and gluons. Protons have been the experimental tool in the discoveries of quarks (charm, bottom, and top), bosons (W(+), W(-), Z(0), and Higgs), antiprotons, and antineutrons. Industrial applications of protons are numerous and important. Additionally, protons are well appreciated in medicine for their role in radiation oncology and in magnetic resonance imaging. Protons are the dominant baryonic subatomic particle in the visible universe, comprising ≈87% of the particle mass. They are present in each atom of our universe and thus a participant in every activity involving matter.

  14. Proton: The Particle

    SciTech Connect

    Suit, Herman

    2013-11-01

    The purpose of this article is to review briefly the nature of protons: creation at the Big Bang, abundance, physical characteristics, internal components, and life span. Several particle discoveries by proton as the experimental tool are considered. Protons play important roles in science, medicine, and industry. This article was prompted by my experience in the curative treatment of cancer patients by protons and my interest in the nature of protons as particles. The latter has been stimulated by many discussions with particle physicists and reading related books and journals. Protons in our universe number ≈10{sup 80}. Protons were created at 10{sup −6} –1 second after the Big Bang at ≈1.37 × 10{sup 10} years beforethe present. Proton life span has been experimentally determined to be ≥10{sup 34} years; that is, the age of the universe is 10{sup −24}th of the minimum life span of a proton. The abundance of the elements is hydrogen, ≈74%; helium, ≈24%; and heavier atoms, ≈2%. Accordingly, protons are the dominant baryonic subatomic particle in the universe because ≈87% are protons. They are in each atom in our universe and thus involved in virtually every activity of matter in the visible universe, including life on our planet. Protons were discovered in 1919. In 1968, they were determined to be composed of even smaller particles, principally quarks and gluons. Protons have been the experimental tool in the discoveries of quarks (charm, bottom, and top), bosons (W{sup +}, W{sup −}, Z{sup 0}, and Higgs), antiprotons, and antineutrons. Industrial applications of protons are numerous and important. Additionally, protons are well appreciated in medicine for their role in radiation oncology and in magnetic resonance imaging. Protons are the dominant baryonic subatomic particle in the visible universe, comprising ≈87% of the particle mass. They are present in each atom of our universe and thus a participant in every activity involving matter.

  15. A versatile approach to N-alkylated 1,4-dideoxy-1,4-imino-D-arabinitols and 1,4-dideoxy-1,4-imino-L-xylitols.

    PubMed

    Wang, Guan-Nan; Yang, Lin; Zhang, Li-He; Ye, Xin-Shan

    2011-04-01

    A versatile and concise synthesis of N-alkylated 1,4-dideoxy-1,4-imino-D-arabinitol and 1,4-dideoxy-1,4-imino-L-xylitol derivatives is described. These were prepared using pseudohemiketal lactams as key intermediates, which in turn were obtained from sucrose. The key intermediates were prepared by a diastereospecific tandem reaction which facilitated the introduction of various substituents on the nitrogen atom of the iminosugars.

  16. 7 CFR 1.4 - Public access to certain materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Public access to certain materials. 1.4 Section 1.4 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Official Records § 1.4 Public access to certain materials. (a) In accordance with 5 U.S.C. 552(a)(2), each agency within the...

  17. 26 CFR 303.1-4 - Computation of taxes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Computation of taxes. 303.1-4 Section 303.1-4... ADMINISTRATION TAXES UNDER THE TRADING WITH THE ENEMY ACT § 303.1-4 Computation of taxes. (a) Detail of employees... computation of tax liability under this part, except as otherwise provided in this part, the vesting...

  18. 47 CFR 1.4 - Computation of time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Computation of time. 1.4 Section 1.4 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE General Rules of Practice and Procedure General § 1.4 Computation of time. (a) Purpose. The purpose of this rule section is to detail the method for computing the amount of...

  19. IRIS Toxicological Review of 1,4-Dioxane (Final Report)

    EPA Science Inventory

    The final Toxicological Review of 1,4-dioxane provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to 1,4-dioxane. Human health risk concerns for 1,4-dioxane are primarily related to exposure from drinking, ground, ...

  20. 5 CFR 1.4 - Extent of the excepted service.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Extent of the excepted service. 1.4 Section 1.4 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE RULES COVERAGE AND DEFINITIONS (RULE I) § 1.4 Extent of the excepted service. (a) The excepted service shall include all...

  1. ESR study of some gamma irradiated amino acids and condensed 1,4-dihydropyridines

    NASA Astrophysics Data System (ADS)

    Aydın, Murat; Şimşek, Rahime; Gündüz, Miyase Gözde; Şafak, Cihat; Osmanoğlu, Y. Emre

    2013-03-01

    L-alanine methyl ester hydrochloride, 2-aminoisobutyric acid and some condensed 1,4-dihydropyridine derivatives (Compounds R1-R4) were gamma irradiated, the induced free radicals was investigated at room temperature by electron spin resonance techniques. The observed paramagnetic species of amino acids compounds were attributed to the CH3ĊHCOOCH3 and (CH3)2ĊCOOH radicals, respectively. The observed spectra of the 1,4-dihydropyridine derivatives interpreted in terms of some type of amine radical fragments. The spectra were computer simulated and the g values of the radicals and the hyperfine structure constants of the unpaired electron with nearby protons and 14N nucleus were determined. In this study, the observed paramagnetic species were found to be stable at room temperature more than 2 months.

  2. 40 CFR 721.990 - 1,4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ester, polymer with 1,4 - butanediol, cyclized. 721.990 Section 721.990 Protection of Environment..., dimethyl ester, polymer with 1,4 - butanediol, cyclized. (a) Chemical substance and significant new uses..., polymer with 1,4 - butanediol, cyclized (PMN P-00-0789; CAS No. 263244-54-8) is subject to reporting...

  3. 40 CFR 721.990 - 1,4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ester, polymer with 1,4 - butanediol, cyclized. 721.990 Section 721.990 Protection of Environment..., dimethyl ester, polymer with 1,4 - butanediol, cyclized. (a) Chemical substance and significant new uses..., polymer with 1,4 - butanediol, cyclized (PMN P-00-0789; CAS No. 263244-54-8) is subject to reporting...

  4. 40 CFR 721.990 - 1,4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ester, polymer with 1,4 - butanediol, cyclized. 721.990 Section 721.990 Protection of Environment..., dimethyl ester, polymer with 1,4 - butanediol, cyclized. (a) Chemical substance and significant new uses..., polymer with 1,4 - butanediol, cyclized (PMN P-00-0789; CAS No. 263244-54-8) is subject to reporting...

  5. 40 CFR 721.990 - 1,4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ester, polymer with 1,4 - butanediol, cyclized. 721.990 Section 721.990 Protection of Environment..., dimethyl ester, polymer with 1,4 - butanediol, cyclized. (a) Chemical substance and significant new uses..., polymer with 1,4 - butanediol, cyclized (PMN P-00-0789; CAS No. 263244-54-8) is subject to reporting...

  6. 40 CFR 721.990 - 1,4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ester, polymer with 1,4 - butanediol, cyclized. 721.990 Section 721.990 Protection of Environment..., dimethyl ester, polymer with 1,4 - butanediol, cyclized. (a) Chemical substance and significant new uses..., polymer with 1,4 - butanediol, cyclized (PMN P-00-0789; CAS No. 263244-54-8) is subject to reporting...

  7. Study of proton radioactivities

    SciTech Connect

    Davids, C.N.; Back, B.B.; Henderson, D.J.

    1995-08-01

    About a dozen nuclei are currently known to accomplish their radioactive decay by emitting a proton. These nuclei are situated far from the valley of stability, and mark the very limits of existence for proton-rich nuclei: the proton drip line. A new 39-ms proton radioactivity was observed following the bombardment of a {sup 96}Ru target by a beam of 420-MeV {sup 78}Kr. Using the double-sided Si strip detector implantation system at the FMA, a proton group having an energy of 1.05 MeV was observed, correlated with the implantation of ions having mass 167. The subsequent daughter decay was identified as {sup 166}Os by its characteristic alpha decay, and therefore the proton emitter is assigned to the {sup 167}Ir nucleus. Further analysis showed that a second weak proton group from the same nucleus is present, indicating an isomeric state. Two other proton emitters were discovered recently at the FMA: {sup 171}Au and {sup 185}Bi, which is the heaviest known proton radioactivity. The measured decay energies and half-lives will enable the angular momentum of the emitted protons to be determined, thus providing spectroscopic information on nuclei that are beyond the proton drip line. In addition, the decay energy yields the mass of the nucleus, providing a sensitive test of mass models in this extremely proton-rich region of the chart of the nuclides. Additional searches for proton emitters will be conducted in the future, in order to extend our knowledge of the location of the proton drip line.

  8. Alteration of gut bacteria and metabolomes after glucaro-1,4-lactone treatment contributes to the prevention of hypercholesterolemia.

    PubMed

    Xie, Baogang; Liu, Aihong; Zhan, Xuejun; Ye, Xinming; Wei, Jing

    2014-07-30

    D-Glucaro-1,4-lactone (1,4-GL) has been shown to have a hypocholesterolemic effect in rats and human subjects. However, little information is known concerning the alteration of metabolome associated with the effect. Here, we show that 1,4-GL delays the development of hypercholesterolemia with the coadministration of a high-fat, high-cholesterol diet (HFHC) in rats. Metabonomic results based on proton nuclear magnetic resonance indicate that urinary trimethylamine N-oxide, trimethylamine, lactate, acetate, formate, and creatinine are significantly altered after 1,4-GL and HFHC treatments. Colonic flora test results reveal that the quantity of Bifidobacterium and Lactobacillus in the intestines respectively increase by about 1.7- and 4.2-fold in rats treated with 1,4-GL compared with those in the control group. Rats that were coadministered with HFHC and 1,4-GL exhibit normal levels of lactate and acetate in serum and display urinary excretions of lactate and acetate that are 2 to 3 times higher compared with those treated with HFHC alone. The results imply that the increased probiotic quantities and urinary excretion of breakdown products of fat/cholesterol after 1,4-GL treatment contribute to the prevention of hypercholesterolemia. Our study offers insights into the model of action for 1,4-GL in preventing hypercholesterolemia.

  9. Lanthanide ion (III) complexes of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraaminophosphonate for dual biosensing of pH with chemical exchange saturation transfer (CEST) and biosensor imaging of redundant deviation in shifts (BIRDS).

    PubMed

    Huang, Yuegao; Coman, Daniel; Ali, Meser M; Hyder, Fahmeed

    2015-01-01

    Relaxivity-based magnetic resonance of phosphonated ligands chelated with gadolinium (Gd(3+)) shows promise for pH imaging. However instead of monitoring the paramagnetic effect of lanthanide complexes on the relaxivity of water protons, biosensor (or molecular) imaging with magnetic resonance is also possible by detecting either the nonexchangeable or the exchangeable protons on the lanthanide complexes themselves. The nonexchangeable protons (e.g. -CHx, where 3 ≥ x ≥ 1) are detected using a three-dimensional chemical shift imaging method called biosensor imaging of redundant deviation in shifts (BIRDS), whereas the exchangeable protons (e.g. -OH or -NHy , where 2 ≥ y ≥ 1) are measured with chemical exchange saturation transfer (CEST) contrast. Here we tested the feasibility of BIRDS and CEST for pH imaging of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraaminophosphonate (DOTA-4AmP(8-)) chelated with thulium (Tm(3+) ) and ytterbium (Yb(3+)). BIRDS and CEST experiments show that both complexes are responsive to pH and temperature changes. Higher pH and temperature sensitivities are obtained with BIRDS for either complex when using the chemical shift difference between two proton resonances vs using the chemical shift of a single proton resonance, thereby eliminating the need to use water resonance as reference. While CEST contrast for both agents is linearly dependent on pH within a relatively large range (i.e. 6.3-7.9), much stronger CEST contrast is obtained with YbDOTA-4AmP(5-) than with TmDOTA-4AmP(5-). In addition, we demonstrate the prospect of using BIRDS to calibrate CEST as new platform for quantitative pH imaging.

  10. Molecular weight distribution of proton irradiated polystyrene studied by diffusion experiments

    NASA Astrophysics Data System (ADS)

    Delto, Ralf; Brenn, Ruediger

    2007-04-01

    MeV ion irradiation of polymers induces break-up or crosslinking of polymer chains. This leads to an ion-fluence dependent molecular weight (MW) distribution ranging from short scission fragments via larger chain clusters to the interconnected, immobile network fraction. We used diffusion experiments to obtain information about the MW distribution of the mobile chains in dependence of the ion fluence. Double layers of deuterated (dPS) and protonated (hPS) polystyrene on Si wafer substrates were irradiated by 1 MeV protons and annealed at 140 °C for various periods of time. The dPS diffusion depth profiles in the irradiation induced hPS network were measured by 3He nuclear reaction analysis. For calibration the strongly MW dependent diffusion coefficients of dPS chains in hPS networks were determined separately by analogous techniques. The depth profiles were fitted with MW dependent diffusion profiles convoluted with a parametrized MW distribution, and the resulting MW distribution was compared to theory.

  11. Startup, Commissioning and Operation of Fenyi 100MW CFB Boiler

    NASA Astrophysics Data System (ADS)

    Wang, Zhiwei; Yu, Wugao; Bo, Shi

    The first 100MW CFB boiler, designed by the Thermal Power Research Institute and manufactured by Harbin Boiler Company Limited, has been successfully running in Jiangxi Fenyi Power Plant since 2003. Local high ash content anthracite and lean coal that are very difficult to burn out are used in the 100 MW CFB boiler. The results of the 100MW CFB boiler shows that the CFB boiler can run in 30% MCR and startup with two under bed burners, and the boiler efficiency higher than 88% can be got after the combustion modification test. The CFB boiler can be operated with full load and reaches design parameters. The emissions of NO, N2O and CO are less than 7Omg/m3, 30mg/m3, and 125mg/m3, respectively, and SO2 less than 400mg/m3 after limestone injection. The bottom ash temperature from bed ash coolers is less than 120°C after its modification. Coal blockage at the coal storage silo is the main problem influencing the CFB boiler continuous operation. The running experiences for 5 years proved that the CFB boiler performance is successful, and the results were applied in 210 MW and 330 MW CFB Boiler design of Fenyi Power Plant.

  12. Development of 1 to 1.5 MW CW Gyrotrons

    NASA Astrophysics Data System (ADS)

    Felch, K.; Blank, M.; Borchard, P.; Cahalan, P.; Cauffman, S.; Chu, S.; Jory, H.

    2003-10-01

    High power mm-wave sources provide electron cyclotron heating, current drive, and instability suppression in fusion plasmas. CPI has delivered three 110 GHz, 1 MW gyrotrons for ECH and ECCD experiments on DIII-D, each of which has demonstrated reliable operation at 1 MW for pulse lengths up to 5 seconds. CPI has also delivered a 140 GHz, 1 MW gyrotron to IPP for use on W-7X. This gyrotron has produced a peak output power of 900 kW, and pulse lengths up to 700 seconds at 500 kW. Ten consecutive 500 kW 600 second pulses were demonstrated without fault at 25CPI's test facilities could not support long pulse operation at full power, such operation is planned at IPP. The 140 GHz system employs a diode magnetron injection gun, a TE_28,7 cavity interaction mode, an internal mode converter to produce a Gaussian output beam, a low-loss CVD diamond output window, and a single-stage depressed-voltage beam collector to enhance the overall electrical efficiency of the device. Currently, under a DOE development program, CPI is fabricating a 110 GHz, 1.3-1.5 MW CW depressed-collector gyrotron to deliver improved reliability at power levels above 1 MW.

  13. Latest Results in SLAC 75-MW PPM Klystrons

    SciTech Connect

    Sprehn, D.; Caryotakis, G.; Haase, A.; Jongewaard, E.; Laurent, L.; Pearson, C.; Phillips, R.; /SLAC

    2006-03-06

    75 MW X-band klystrons utilizing Periodic Permanent Magnet (PPM) focusing have been undergoing design, fabrication and testing at the Stanford Linear Accelerator Center (SLAC) for almost nine years. The klystron development has been geared toward realizing the necessary components for the construction of the Next Linear Collider (NLC). The PPM devices built to date which fit this class of operation consist of a variety of 50 MW and 75 MW devices constructed by SLAC, KEK (Tsukuba, Japan) and industry. All these tubes follow from the successful SLAC design of a 50 MW PPM klystron in 1996. In 2004 the latest two klystrons were constructed and tested with preliminary results reported at EPAC2004. The first of these two devices was tested to the full NLC specifications of 75 MW, 1.6 microseconds pulse length, and 120 Hz. This 14.4 kW average power operation came with a tube efficiency >50%. The most recent testing of these last two devices will be presented here. Design and manufacturing issues of the latest klystron, due to be tested by the Fall of 2005, are also discussed.

  14. 49 CFR 172.523 - EXPLOSIVES 1.4 placard.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false EXPLOSIVES 1.4 placard. 172.523 Section 172.523... SECURITY PLANS Placarding § 172.523 EXPLOSIVES 1.4 placard. (a) Except for size and color, the EXPLOSIVES 1... subpart, the background color on the EXPLOSIVES 1.4 placard must be orange. The “*” shall be...

  15. 49 CFR 172.523 - EXPLOSIVES 1.4 placard.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false EXPLOSIVES 1.4 placard. 172.523 Section 172.523... SECURITY PLANS Placarding § 172.523 EXPLOSIVES 1.4 placard. (a) Except for size and color, the EXPLOSIVES 1... subpart, the background color on the EXPLOSIVES 1.4 placard must be orange. The “*” shall be...

  16. 49 CFR 172.523 - EXPLOSIVES 1.4 placard.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false EXPLOSIVES 1.4 placard. 172.523 Section 172.523... SECURITY PLANS Placarding § 172.523 EXPLOSIVES 1.4 placard. (a) Except for size and color, the EXPLOSIVES 1... subpart, the background color on the EXPLOSIVES 1.4 placard must be orange. The “*” shall be...

  17. 49 CFR 172.523 - EXPLOSIVES 1.4 placard.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false EXPLOSIVES 1.4 placard. 172.523 Section 172.523... SECURITY PLANS Placarding § 172.523 EXPLOSIVES 1.4 placard. (a) Except for size and color, the EXPLOSIVES 1... subpart, the background color on the EXPLOSIVES 1.4 placard must be orange. The “*” shall be...

  18. 49 CFR 172.523 - EXPLOSIVES 1.4 placard.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false EXPLOSIVES 1.4 placard. 172.523 Section 172.523... SECURITY PLANS Placarding § 172.523 EXPLOSIVES 1.4 placard. (a) Except for size and color, the EXPLOSIVES 1... subpart, the background color on the EXPLOSIVES 1.4 placard must be orange. The “*” shall be...

  19. Proton-conducting cerate ceramics

    SciTech Connect

    Pederson, L.R.; Coffey, G.W.; Bates, J.L.; Weber, W.J.

    1996-08-01

    Single-cell solid oxide fuel cells were constructed using strontium cerate as the electrolyte and their performance tested. Like certain zirconates, hafnates, and tantalates, the cerate perovskites are among a class of solid electrolytes that conduct protons at elevated temperatures. Depending on the temperature and chemical environment, these ceramics also support electronic and oxygen ion currents. A maximum power output of {approx}100 mW per cm{sup 2} electrolyte surface area was obtained at 900{degrees}C using 4% hydrogen as the fuel and air as the oxidant. A series of rare earth/ceria/zirconia were prepared and their electrical properties characterized. Rare earth dopants included ytterbia, yttria, terbia, and europia. Ionic conductivities were highest for rare earth/ceria and rare earth zirconia compositions; a minimum in ionic conductivity for all series were found for equimolar mixtures of ceria and zirconia. Cerium oxysulfide is of interest in fossil energy applications because of its high chemical stability and refractory nature. An alternative synthesis route to preparing cerium oxysulfide powders has been developed using combustion techniques.

  20. The 1.5 MW wind turbine of tomorrow

    SciTech Connect

    De Wolff, T.J.; Sondergaard, H.

    1996-12-31

    The Danish company Nordtank is one of the pioneers within the wind turbine industry. Since 1981 Nordtank has installed worldwide more than 2300 wind turbine generators with a total name plate capacity that is exceeding 350 MW. This paper will describe two major wind turbine technology developments that Nordtank has accomplished during the last year: Site Optimization of Nordtank wind turbines: Nordtank has developed a flexible design concept for its WTGs in the 500/600 kW range, in order to offer the optimal WTG solution for any given site and wind regime. Nordtank`s 1.5 MW wind turbine: In September 1995, Nordtank was the first company to install a commercial 1.5 NM WTG. This paper will document the development process, the design as well as operations of the Nordtank 1.5 MW WTG.

  1. Molecular cloning and functional expression of a novel Helicobacter pylori alpha-1,4 fucosyltransferase.

    PubMed

    Rabbani, Said; Miksa, Viktoria; Wipf, Beat; Ernst, Beat

    2005-11-01

    Helicobacter pylori is an important human pathogen which causes both gastric and duodenal ulcers and is associated with gastric cancer and lymphoma. This microorganism synthesizes fucosylated oligosaccharides, predominantly the Galb-1,4GlcNAc (Type II) blood group antigens Lewis X and Y, whereas a small population also expresses the Galb-1,3GlcNAc (Type I) blood group antigens Lewis A and B. These carbohydrate structures are known to mimic host cell antigens and permit the bacteria to escape from the host immune response. Here, we report the cloning and characterization of a novel H. pylori alpha-1,4 fucosyltransferase (FucT). In contrast to the family members characterized to date, this enzyme shows exclusively Type I acceptor substrate specificity. The enzyme consisting of 432 amino acids (MW 50,502 Da) was cloned using a polymerase chain reaction (PCR)-based approach. It exhibits a high degree of identity (75-87%) and similar structural features, for example, in the heptamer repeat pattern, with other H. pylori FucTs. The kinetic characterization revealed a very efficient transferase (k(cat)/Km = 229 mM(-1) s(-1)) for the Type I acceptor substrate (Gal)-1,3 GlcNAc-Lem (1). Additionally, the enzyme possesses a broad tolerance toward nonnatural Type I acceptor substrate analogs and therefore represents a valuable tool for the chemoenzymatic synthesis of Lewis A, sialyl Lewis A as well as mimetics thereof.

  2. 43 CFR 3425.1-4 - Emergency leasing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Emergency leasing. 3425.1-4 Section 3425.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) COMPETITIVE LEASING Leasing on Application § 3425.1-4 Emergency leasing. (a) An emergency lease sale may be held in response to an application under this...

  3. 43 CFR 3425.1-4 - Emergency leasing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Emergency leasing. 3425.1-4 Section 3425.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) COMPETITIVE LEASING Leasing on Application § 3425.1-4 Emergency leasing. (a) An emergency lease sale may be held in response to an application under this...

  4. 43 CFR 3425.1-4 - Emergency leasing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Emergency leasing. 3425.1-4 Section 3425.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) COMPETITIVE LEASING Leasing on Application § 3425.1-4 Emergency leasing. (a) An emergency lease sale may be held in response to an application under this...

  5. IRIS Toxicological Review of 1,4-Dioxane (Final Report)

    EPA Science Inventory

    EPA announced the release of the final report, Toxicological Review of 1,4-Dioxane (CAS No. 123-91-1): In Support of Summary Information on the Integrated Risk Information System (IRIS). The final Toxicological Review of 1,4-dioxane provides scientific support and rationa...

  6. Photochemistry Of 2,5-Diacyl-1, 4-Dimethylbenzenes

    NASA Technical Reports Server (NTRS)

    Meador, Michael A.

    1989-01-01

    Experiments described in report revealed potentially useful aspects of photochemistry of 2,5-dibenzoyl-1, 4-dimethylbenzene (DBX) and 2,5-diacetyl-1, 4-dimethylbenzene (DAX). Behavior of these compounds reminiscent of orthoalkylphenyl ketones, studied from similar perspective for more than two decades.

  7. First Synthesis of 1,4-Dimethoxy-2-Naphthoxyacetic acid.

    PubMed

    Chinea, Kimberly; Banerjee, Ajoy K

    2015-07-01

    2-Acetyl-1-hydroxynaphthalene was converted into 1,4-dimethoxy-2-naphthoxyacetic acid in seven steps (methylation, Bayer-Villiger oxidation, hydrolysis, bromination, methylation, alkylation and hydrolysis). 2-Hydroxy-1,4-naphthoquinone on acetylation, aromatization, methylation and hydrolysis, respectively, also yielded the title compound.

  8. 17 CFR 1.4 - Use of electronic signatures.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Use of electronic signatures. 1.4 Section 1.4 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION GENERAL... pool participant or a client of a commodity trading advisor, an electronic signature executed by...

  9. 17 CFR 1.4 - Use of electronic signatures.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 1 2012-04-01 2012-04-01 false Use of electronic signatures. 1.4 Section 1.4 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION GENERAL... pool participant or a client of a commodity trading advisor, an electronic signature executed by...

  10. Radiolabeling of Cramoll 1,4: Evaluation of the Biodistribution

    PubMed Central

    Ferreira de Carvalho Patricio, Beatriz; Lima-Ribeiro, Maria Helena Madruga; dos Santos Correia, Maria Tereza; dos Anjos Carneiro-Leão, Ana Maria; de Souza Albernaz, Marta; Barboza, Thiago; de Souza, Sergio Augusto Lopes; Santos-Oliveira, Ralph

    2011-01-01

    The cramoll 1,4 is a well-studied lectin. However, few studies about its biodistribution have been done before. In this study, we radiolabeled the cramol 1,4 with Tc-99m and analyzed the biodistribution. The results showed that the cramol has an abnormal uptake by the bowel with reflections on its clearance mechanism. PMID:21760823

  11. 43 CFR 3425.1-4 - Emergency leasing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Emergency leasing. 3425.1-4 Section 3425.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) COMPETITIVE LEASING Leasing on Application § 3425.1-4 Emergency leasing. (a) An emergency lease sale may be held in response to an application under this...

  12. Design of Electron Gun for 1.5 MW, 140 GHz Gyrotron

    NASA Astrophysics Data System (ADS)

    Singh, Udaybir; Kumar, Nitin; Purohit, L. P.; Sinha, A. K.

    2011-02-01

    This paper presents the design of the triode type electron gun for a 140 GHz, 1.5 MW gyrotron with the transverse to the axial velocity ratio of the beam 1.4 and the transverse velocity spread 1.28%. The operating mode of the gyrotron is TE24,8 and it is operated in the fundamental harmonic. The analytic trade-off equations for the electron gun design have been used to estimate the initial gun parameters. The electron trajectory tracing program has been used to optimize the electron gun design. The parametric dependences of modulating anode voltage, beam voltage and cathode magnetic field on the beam quality has also been studied.

  13. Sacremento Municipal Utility District 100-MW sub e photovoltaic plant

    NASA Technical Reports Server (NTRS)

    Powell, R. V.

    1982-01-01

    A status report on plans for the Sacramento Municipal Utility District (SMUD) 1-MW photovoltaic power plant is presented. DOE, the California Energy Commission, and SMUD will fund the project cooperatively. Emphasis is placed on the details of the government contract/cooperation agreement.

  14. Design of a 50 MW klystron at X-band

    SciTech Connect

    Wright, E.; Callin, R.; Caryotakis, G.

    1995-07-01

    This paper describes the design and performance of the XL-1 klystron; a 50 MW klystron operating at a frequency of 11.424 GHz for use on the SLAC Next Linear Collider Test Accelerator (NLCTA). Problems associated with the development of high-power rf sources for NLC, and the solutions implemented on XL-1 are discussed.

  15. MW 08-multi-beam air and surface surveillance radar

    NASA Astrophysics Data System (ADS)

    1989-09-01

    Signal of the Netherlands has developed and is marketing the MW 08, a 3-D radar to be used for short to medium range surveillance, target acquisition, and tracking. MW 08 is a fully automated detecting and tracking radar. It is designed to counter threats from aircraft and low flying antiship missiles. It can also deal with the high level missile threat. MW 08 operates in the 5 cm band using one antenna for both transmitting and receiving. The antenna is an array, consisting of 8 stripline antennas. The received radar energy is processed by 8 receiver channels. These channels come together in the beam forming network, in which 8 virtual beams are formed. From this beam pattern, 6 beams are used for the elevation coverage of 0-70 degrees. MW 08's output signals of the beam former are further handled by FFT and plot processors for target speed information, clutter rejection, and jamming suppression. A general purpose computer handles target track initiation, and tracking. Tracking data are transferred to the command and control systems with 3-D target information for fastest possible lockon.

  16. Lightweight MgB2 superconducting 10 MW wind generator

    NASA Astrophysics Data System (ADS)

    Marino, I.; Pujana, A.; Sarmiento, G.; Sanz, S.; Merino, J. M.; Tropeano, M.; Sun, J.; Canosa, T.

    2016-02-01

    The offshore wind market demands a higher power rate and more reliable turbines in order to optimize capital and operational costs. The state-of-the-art shows that both geared and direct-drive conventional generators are difficult to scale up to 10 MW and beyond due to their huge size and weight. Superconducting direct-drive wind generators are considered a promising solution to achieve lighter weight machines. This work presents an innovative 10 MW 8.1 rpm direct-drive partial superconducting generator using MgB2 wire for the field coils. It has a warm iron rotor configuration with the superconducting coils working at 20 K while the rotor core and the armature are at ambient temperature. A cooling system based on cryocoolers installed in the rotor extracts the heat from the superconducting coils by conduction. The generator's main parameters are compared against a permanent magnet reference machine, showing a significant weight and size reduction. The 10 MW superconducting generator concept will be experimentally validated with a small-scale magnetic machine, which has innovative components such as superconducting coils, modular cryostats and cooling systems, and will have similar size and characteristics as the 10 MW generator.

  17. Mw Dependence of Ionospheric Electron Enhancement Immediately Before Large Earthquakes

    NASA Astrophysics Data System (ADS)

    Heki, K.; He, L.

    2015-12-01

    Ionospheric electrons were reported to have increased ~40 minutes before the 2011 Tohoku-oki (Mw9.0) earthquake, Japan, by observing total electron content (TEC) with GNSS receivers [e.g. Heki and Enomoto, 2013]. They further demonstrated that similar TEC enhancements preceded all the recent earthquakes with Mw of 8.5 or more. Their reality has been repeatedly questioned due mainly to the ambiguity in the derivation of the reference TEC curves from which anomalies are defined [e.g. Masci et al., 2015]. Here we propose a numerical approach, based on Akaike's Information Criterion, to detect positive breaks (sudden increase of TEC rate) in the vertical TEC time series without using reference curves. We demonstrate that such breaks are detected 20-80 minutes before the ten recent large earthquakes with Mw7.8-9.2. The amounts of breaks were found to depend on the background absolute VTEC and Mw, i.e. Break (TECU/h)=4.74Mw+0.13VTEC-39.86, with the standard deviation of ~1.2 TECU/h. We can convert this equation to Mw = (Break-0.13VTEC+39.86)/4.74, which can tell us the Mw of impending earthquakes with uncertainty of ~0.25. The precursor times were longer for larger earthquakes, ranging from ~80 minutes for the largest (2004 Sumatra-Andaman) to ~21 minutes for the smallest (2015 Nepal). The precursors of intraplate earthquakes (e.g. 2012 Indian Ocean) started significantly earlier than interplate ones. We performed the same analyses during periods without earthquakes, and found that positive breaks comparable to that before the 2011 Tohoku-oki earthquake occur once in 20 hours. They originate from small amplitude Large-scale Travelling Ionospheric Disturbances (LSTID), which are excited in the auroral oval and move southward with the velocity of internal gravity waves. This probability is small enough to rule out the fortuity of these breaks, but large enough to make it a challenge to apply preseismic TEC enhancements for short-term earthquake prediction.

  18. Electron-proton spectrometer

    NASA Technical Reports Server (NTRS)

    Winckler, J. R.

    1973-01-01

    An electron-proton spectrometer was designed to measure the geomagnetically trapped radiation in a geostationary orbit at 6.6 earth radii in the outer radiation belt. This instrument is to be flown on the Applications Technology Satellite-F (ATS-F). The electron-proton spectrometer consists of two permanent magnet surface barrier detector arrays and associated electronics capable of selecting and detecting electrons in three energy ranges: (1) 30-50 keV, (2) 150-200 keV, and (3) 500 keV and protons in three energy ranges. The electron-proton spectrometer has the capability of measuring the fluxes of electrons and protons in various directions with respect to the magnetic field lines running through the satellite. One magnet detector array system is implemented to scan between EME north and south through west, sampling the directional flux in 15 steps. The other magnet-detector array system is fixed looking toward EME east.

  19. Surface Protonics Promotes Catalysis

    NASA Astrophysics Data System (ADS)

    Manabe, R.; Okada, S.; Inagaki, R.; Oshima, K.; Ogo, S.; Sekine, Y.

    2016-12-01

    Catalytic steam reforming of methane for hydrogen production proceeds even at 473 K over 1 wt% Pd/CeO2 catalyst in an electric field, thanks to the surface protonics. Kinetic analyses demonstrated the synergetic effect between catalytic reaction and electric field, revealing strengthened water pressure dependence of the reaction rate when applying an electric field, with one-third the apparent activation energy at the lower reaction temperature range. Operando–IR measurements revealed that proton conduction via adsorbed water on the catalyst surface occurred during electric field application. Methane was activated by proton collision at the Pd–CeO2 interface, based on the inverse kinetic isotope effect. Proton conduction on the catalyst surface plays an important role in methane activation at low temperature. This report is the first describing promotion of the catalytic reaction by surface protonics.

  20. Surface Protonics Promotes Catalysis

    PubMed Central

    Manabe, R.; Okada, S.; Inagaki, R.; Oshima, K.; Ogo, S.; Sekine, Y.

    2016-01-01

    Catalytic steam reforming of methane for hydrogen production proceeds even at 473 K over 1 wt% Pd/CeO2 catalyst in an electric field, thanks to the surface protonics. Kinetic analyses demonstrated the synergetic effect between catalytic reaction and electric field, revealing strengthened water pressure dependence of the reaction rate when applying an electric field, with one-third the apparent activation energy at the lower reaction temperature range. Operando–IR measurements revealed that proton conduction via adsorbed water on the catalyst surface occurred during electric field application. Methane was activated by proton collision at the Pd–CeO2 interface, based on the inverse kinetic isotope effect. Proton conduction on the catalyst surface plays an important role in methane activation at low temperature. This report is the first describing promotion of the catalytic reaction by surface protonics. PMID:27905505

  1. Subchronic Toxicity Study on 1,4-Dithiane.

    DTIC Science & Technology

    1987-08-01

    respectively. The left-ear clipped control male in cage 14 had malocclusion (a bite defect) and was excluded from all statistical analyses. An ANOVA on the...have the nose crystals. The time required for deposition of the nose crystals is important for a risk assessment analysis for 1,4-dithiane. 3) Studying...regression of the 1,4-dithiane-induced tissue damage is essential for a risk -assessment analysis for 1,4-dithiane. 4.) Studying the strain and species

  2. Dynamic Heterogeneity and Density Scaling In 1,4-Polyisoprene

    DTIC Science & Technology

    2011-01-01

    Changes in V were carried out by isobaric changes in T from 0 to -74 C (squares) or isothermal changes inP up to as high as 750MPa (all other symbols...is the difference in the inverse of the isobaric heat capacities for the liquid and glass atTg (note that the choice of Δcp -1 rather than the (Δcp...times for the lowest (open symbols) and highest Mw (dotted symbols). Each symbol is a distinct isotherm or isobar . The value of γ was chosen to minimize

  3. Proton-proton colliding beam facility ISABELLE

    SciTech Connect

    Hahn, H

    1980-01-01

    This paper attempts to present the status of the ISABELLE construction project, which has the objective of building a 400 + 400 GeV proton colliding beam facility. The major technical features of the superconducting accelerators with their projected performance are described. Progress made so far, difficulties encountered, and the program until completion in 1986 is briefly reviewed.

  4. Vibrational frequencies and structural determinations of 1,4-thioxane

    NASA Astrophysics Data System (ADS)

    Ellzy, Michael W.; Jensen, James O.; Hameka, Hendrik F.; Kay, Jack G.; Zeroka, Daniel

    2001-10-01

    We present a detailed analysis of the structure and infrared spectra of 1,4-thioxane. The vibrational frequencies of the 1,4-thioxane molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-31G* basis set. The structural transformation of the chemical agent bis (2-chloroethyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compound (4) makes the symmetry of the 1,4-thioxane molecule an interesting candidate for study. The molecule exists normally in a C s configuration similar to the chair form of cyclohexane. High-energy forms of 1,4-thioxane with C 1 and C 2 symmetry also exist.

  5. Technical Fact Sheet – 1,4-Dioxane

    EPA Pesticide Factsheets

    This fact sheet, developed by the U.S. Environmental Protection Agency (EPA) Federal Facilities Restoration and Reuse Office (FFRRO), provides a brief summary of the contaminant 1,4-dioxane, including physical and chemical properties

  6. 12 CFR 1.4 - Calculation of limits.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Calculation of limits. (a) Calculation date. For purposes of determining compliance with 12 U.S.C. 24 (Seventh... change in the bank's capital category for purposes of 12 U.S.C. 1831o and 12 CFR 6.3. (b) Effective date... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Calculation of limits. 1.4 Section 1.4...

  7. 12 CFR 1.4 - Calculation of limits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Calculation of limits. (a) Calculation date. For purposes of determining compliance with 12 U.S.C. 24 (Seventh... change in the bank's capital category for purposes of 12 U.S.C. 1831o and 12 CFR 6.3. (b) Effective date... 12 Banks and Banking 1 2011-01-01 2011-01-01 false Calculation of limits. 1.4 Section 1.4...

  8. Architecture Earth-Sheltered Buildings. Design Manual 1.4

    DTIC Science & Technology

    1984-03-01

    Bioclimat kpproach to Architectural Regionalismj Princeton, New Jersey, Princetk .niversity Press, 1963. " 7) 3. Givoni, B., Man, Climate and...AD-A 140 831 NAVFAC DM-1.4MARCH 1984 T OF ARCHITECTURE EARTH-SHELTERED BUILDINGS DESIGN MANUAL 1.4 Reproduced From Best Available Copy ~9J)O,3...design are included for the following disciplines: Planniing, Landscape Design, Life-Cycle Analysis, Architectural , Structural, Mechanical (criteria

  9. Proton therapy in Japan

    SciTech Connect

    Tsunemoto, H.; Morita, S.; Ishikawa, T.; Furukawa, S.; Kawachi, K.; Kanai, T.; Ohara, H.; Kitagawa, T.; Inada, T.

    1985-01-01

    There are two facilities for clinical trials with protons in Japan: the National Institute of Radiological Sciences (NIRS), Chiba, and the Particle Radiation Medical Science Center (PARMS), University of Tsukuba. At the National Institute of Radiological Sciences, patient treatment with the 70 MeV proton beam began in November 1979, and 29 patients were treated through December 1984. Of 11 patients who received protons only, 9 have had local control of the tumor. Two of the 9 patients, suffering from recurrent tumor after radical photon beam irradiation, developed complications after proton treatment. In the patients treated with photons or neutrons followed by proton boost, tumors were controlled in 12 of 18 patients (66.6%), and no complications were observed in this series. Malignant melanoma could not be controlled with the proton beam. A spot-beam-scanning system for protons has been effectively used in the clinical trials to minimize the dose to the normal tissues and to concentrate the dose in the target volume. At the Particle Radiation Medical Science Center, University of Tsukuba, treatment with a vertical 250 MeV proton beam was begun in April 1983, and 22 patients were treated through February 1984. Local control of the tumor was observed in 14 of 22 patients (63.6%), whereas there was no local control in the treatment of glioblastoma multiforme. There have been no severe complications in patients treated at PARMS. The results suggest that local control of tumors will be better with proton beams than with photon beams, whereas additional modalities are required to manage radioresistant tumors.

  10. The Proton launcher

    NASA Astrophysics Data System (ADS)

    Bond, A.; Parfitt, J.

    1985-08-01

    The capabilities, design features and missions for the Soviet Proton booster are described. The Proton, outfitted with six strap-on boosters, launched the Vega 1 and 2 Venus/Halley dual mission spacecraft. RD-253 engines burn N2O4 and UDMH fuels, possibly through a preburner before the combustion chamber. A vacuum thrust of 450,000 lb is projected for the engine. Analyses are presented to set the launch weight at 1,600,000 lb, implying that the vehicle is based on an ICBM design. It is suggested that the Proton has sufficiently high noise and vibration levels to prohibit it from being man-rated.

  11. Are protons nonidentical fermions?

    SciTech Connect

    Mart, T.

    2014-09-25

    We briefly review the progress of our investigation on the electric (charge) radius of the proton. In order to explain the recently measured proton radius, which is significantly smaller than the standard CODATA value, we assume that the real protons radii are not identical, they are randomly distributed in a certain range. To obtain the measured radius we average the radii and fit both the mean radius and the range. By using an averaged dipole form factor we obtain the charge radius r{sub E} = 0.8333 fm, in accordance with the recent measurement of the Lamb shift in muonic hydrogen.

  12. Acyloxylation of 1,4-Dioxanes and 1,4-Dithianes Catalyzed by a Copper-Iron Mixed Oxide.

    PubMed

    García-Cabeza, Ana Leticia; Marín-Barrios, Rubén; Moreno-Dorado, F Javier; Ortega, María J; Vidal, Hilario; Gatica, José M; Massanet, Guillermo M; Guerra, Francisco M

    2015-07-02

    The use of a copper-iron mixed oxide as a heterogeneous catalyst for the efficient synthesis of α-acyloxy-1,4-dioxanes and 1,4-dithianes employing t-butyl peroxyesters is reported. The preparation and characterization of the catalyst are described. The effect of the heteroatoms and a plausible mechanism are discussed. The method is operationally simple and involves low-cost starting materials affording products in good to excellent yields.

  13. 10 MW, L-Band Klystron for Accelerators

    SciTech Connect

    Read, Michael; Ives, Robert L.; Ferguson, Patrick

    2016-03-07

    This program developed a 10 MW, pulsed, Annular Beam Klystron (ABK) for accelerator applications. This is an alternative RF source to multiple beam klystrons MBKs), which are more complex and considerably more expensive. The ABK uses a single, annular cathode and a single beam tunnel with fundamental mode cavities. The operating specifications (voltage, efficiency, power, bndwidth, duty, etc.) are the same as for comparable MBKs.

  14. SPALLATION NEUTRON SOURCE OPERATIONAL EXPERIENCE AT 1 MW

    SciTech Connect

    Galambos, John D

    2011-01-01

    The Spallation Neutron Source (SNS) has been operating at the MW level for about one year. Experience in beam loss control and machine activation at this power level is presented. Also experience with machine protection systems is reviewed, which is critical at this power level. One of the most challenging operational aspects of high power operation has been attaining high availability, which is also discussed

  15. Physics and Chemistry of MW Discharge in Gas Flows

    DTIC Science & Technology

    2007-11-02

    this working regime of wind tunnel. Measurement was carried out by means of pneumatic probes. 1.1.1. Experimental conditions Nozzle with Mach number 2.1...unstable objects may be Laser Thomson Scattering Technique. Created laser Thomson Final Report 30 July, 2004 Project 2014p IHT-SPSU scattering...experimental scheme for investigation of Thomson scattering in MW discharge in SS flow with static pressure 20 - 50 Torr and Mach number 1.5 - 2. Impulse

  16. Parity Nonconservation in Proton-Proton and Proton-Water Scattering at 1.5 GeV/c

    DOE R&D Accomplishments Database

    Mischke, R. E.; Bowman, J. D.; Carlini, R.; MacArthur, D.; Nagle, D. E.; Frauenfelder, H.; Harper, R. W.; Yuan, V.; McDonald, A. B.; Talaga, R. L.

    1984-07-01

    Experiments searching for parity nonconservation in the scattering of 1.5 GeV/c (800 MeV) polarized protons from an unpolarized water target and a liquid hydrogen target are described. The intensity of the incident proton beam was measured upstream and downstream of the target by a pair of ionization detectors. The beam helicity was reversed at a 30-Hz rate. Auxiliary detectors monitored beam properties that could give rise to false effects. The result for the longitudinal asymmetry from the water is A{sub L} = (1.7 +- 3.3 +- 1.4) x 10{sup -7}, where the first error is statistical and the second is an estimate of systematic effects. The hydrogen data yield a preliminary result of A{sub L} = (1.0 +- 1.6) x 10{sup -7}. The systematic errors for p-p are expected to be < 1 x 10{sup -7}.

  17. Uncertainty estimates for proton-proton fusion

    NASA Astrophysics Data System (ADS)

    Acharya, Bijaya

    2017-01-01

    We calculate the proton-proton fusion cross section using chiral effective field theory (χEFT) and perform a rigorous analysis of the associated uncertainties. The statistical errors in the low-energy constants, which are fitted too scattering and bound-state observables in the pion-nucleon, nucleon-nucleon, and few-nucleon sectors, are propagated to the calculated cross section. We also investigate the sensitivity of the fusion cross section to the high-momentum cutoff of the χEFT. We extract a value for the zero-energy S-factor using a polynomial extrapolant and analyze the errors associated with this procedure. Our result is compared to that of another χEFT calculation in which the wave functions were represented in a truncated Hilbert space with discrete basis states. Supported by the NSF under Grant Nos. PHY-1516077 and PHY- 1555030.

  18. Apparatus for proton radiography

    DOEpatents

    Martin, Ronald L.

    1976-01-01

    An apparatus for effecting diagnostic proton radiography of patients in hospitals comprises a source of negative hydrogen ions, a synchrotron for accelerating the negative hydrogen ions to a predetermined energy, a plurality of stations for stripping extraction of a radiography beam of protons, means for sweeping the extracted beam to cover a target, and means for measuring the residual range, residual energy, or percentage transmission of protons that pass through the target. The combination of information identifying the position of the beam with information about particles traversing the subject and the back absorber is performed with the aid of a computer to provide a proton radiograph of the subject. In an alternate embodiment of the invention, a back absorber comprises a plurality of scintillators which are coupled to detectors.

  19. The Proton Radius Puzzle

    NASA Astrophysics Data System (ADS)

    Downie, E. J.

    2016-03-01

    The proton radius puzzle is the difference between the proton radius as measured with electron scattering and in the excitation spectrum of atomic hydrogen, and that measured with muonic hydrogen spectroscopy. Since the inception of the proton radius puzzle in 2010 by the measurement of Pohl et al.[1], many possible resolutions to the puzzle have been postulated, but, to date, none has been generally accepted. New data are therefore necessary to resolve the issue. We briefly review the puzzle, the proposed solutions, and the new electron scattering and spectroscopy experiments planned and underway. We then introduce the MUSE experiment, which seeks to resolve the puzzle by simultaneously measuring elastic electron and muon scattering on the proton, in both charge states, thereby providing new information to the puzzle. MUSE addresses issues of two-photon effects, lepton universality and, possibly, new physics, while providing simultaneous form factor, and therefore radius, measurements with both muons and electrons.

  20. Proton channel models

    PubMed Central

    Pupo, Amaury; Baez-Nieto, David; Martínez, Agustín; Latorre, Ramón; González, Carlos

    2014-01-01

    Voltage-gated proton channels are integral membrane proteins with the capacity to permeate elementary particles in a voltage and pH dependent manner. These proteins have been found in several species and are involved in various physiological processes. Although their primary topology is known, lack of details regarding their structures in the open conformation has limited analyses toward a deeper understanding of the molecular determinants of their function and regulation. Consequently, the function-structure relationships have been inferred based on homology models. In the present work, we review the existing proton channel models, their assumptions, predictions and the experimental facts that support them. Modeling proton channels is not a trivial task due to the lack of a close homolog template. Hence, there are important differences between published models. This work attempts to critically review existing proton channel models toward the aim of contributing to a better understanding of the structural features of these proteins. PMID:24755912

  1. LBNF 1.2 MW TARGET: CONCEPTUAL DESIGN & FABRICATION

    SciTech Connect

    Crowley, Cory F.; Ammigan, K.; Anderson, K.; Hartsell, B.; Hurh, P.; Hylen, J.; Zwaska, R.

    2015-06-29

    Fermilab’s Long-Baseline Neutrino Facility (LBNF) will utilize a modified design based on the NuMI low energy target that is reconfigured to accommodate beam operation at 1.2 MW. Achieving this power with a graphite target material and ancillary systems originally rated for 400 kW requires several design changes and R&D efforts related to material bonding and electrical isolation. Target cooling, structural design, and fabrication techniques must address higher stresses and heat loads that will be present during 1.2 MW operation, as the assembly will be subject to cyclic loads and thermal expansion. Mitigations must be balanced against compromises in neutrino yield. Beam monitoring and subsystem instrumentation will be updated and added to ensure confidence in target positioning and monitoring. Remote connection to the target hall support structure must provide for the eventual upgrade to a 2.4 MW target design, without producing excessive radioactive waste or unreasonable exposure to technicians during reconfiguration. Current designs and assembly layouts will be presented, in addition to current findings on processes and possibilities for prototype and final assembly fabrication.

  2. Low Beam Voltage, 10 MW, L-Band Cluster Klystron

    SciTech Connect

    Teryaev, V.; Yakovlev, V.P.; Kazakov, S.; Hirshfield, J.L.; /Yale U. /Omega-P, New Haven

    2009-05-01

    Conceptual design of a multi-beam klystron (MBK) for possible ILC and Project X applications is presented. The chief distinction between this MBK design and existing 10-MW MBK's is the low operating voltage of 60 kV. There are at least four compelling reasons that justify development at this time of a low-voltage MBK, namely (1) no pulse transformer; (2) no oil tank for high-voltage components and for the tube socket; (3) no high-voltage cables; and (4) modulator would be a compact 60-kV IGBT switching circuit. The proposed klystron consists of four clusters containing six beams each. The tube has common input and output cavities for all 24 beams, and individual gain cavities for each cluster. A closely related optional configuration, also for a 10 MW tube, would involve four totally independent cavity clusters with four independent input cavities and four 2.5 MW output ports, all within a common magnetic circuit. This option has appeal because the output waveguides would not require a controlled atmosphere, and because it would be easier to achieve phase and amplitude stability as required in individual SC accelerator cavities.

  3. Performance of 500 MW coal fired steam generators

    SciTech Connect

    Kumar, R.; Zachariah, J.

    1996-11-01

    Bharat Heavy Electricals Limited in association with ABB-CE, USA has engineered and supplied twelve 500 MW units. The first steam generator is in service from 1984. The design of these 500 MW steam generators was based on the experience of the 200 and 210 MW units. The Indian coals have high ash content, lower calorific value and high moisture experienced during rainy season. Because of this there were a few performance problems in the first few units. The experience of assessing and improving the performance of these steam generators is the main theme of this paper. The combustion characteristics of the Indian coals are good. However, the high ash content and low calorific value associated with high moisture required specific changes in steam generator design. Tests done in different units with different coals helped in analyzing the problem. The analysis of the test data resulted in engineering changes. The modifications done improved the performance of these units. It also helped in updating design standards and methods. The paper gives an outline of the key aspects to look for in steam generator design for high ash Indian coals. The paper also outlines the testing and performance analysis methods used.

  4. Proton beam therapy facility

    SciTech Connect

    Not Available

    1984-10-09

    It is proposed to build a regional outpatient medical clinic at the Fermi National Accelerator Laboratory (Fermilab), Batavia, Illinois, to exploit the unique therapeutic characteristics of high energy proton beams. The Fermilab location for a proton therapy facility (PTF) is being chosen for reasons ranging from lower total construction and operating costs and the availability of sophisticated technical support to a location with good access to patients from the Chicago area and from the entire nation. 9 refs., 4 figs., 26 tabs.

  5. Electronic properties of hydrogen-bonded complexes of benzene(HCN)(1-4): comparison with benzene(H2O)(1-4).

    PubMed

    Mateus, M P S; Galamba, N; Cabral, B J Costa

    2011-11-24

    The electronic properties, specifically, the dipole and quadrupole moments and the ionization energies of benzene (Bz) and hydrogen cyanide (HCN), and the respective binding energies, of complexes of Bz(HCN)(1-4), have been studied through MP2 and OVGF calculations. The results are compared with the properties of benzene-water complexes, Bz(H(2)O)(1-4), with the purpose of analyzing the electronic properties of microsolvated benzene, with respect to the strength of the CH/π and OH/π hydrogen-bond (H-bond) interactions. The linear HCN chains have the singular ability to interact with the aromatic ring, preserving the symmetry of the latter. A blue shift of the first vertical ionization energies (IEs) of benzene is observed for the linear Bz(HCN)(1-4) clusters, which increases with the length of the chain. NBO analysis indicates that the increase of the IE with the number of HCN molecules is related to a strengthening of the CH/π H-bond, driven by cooperative effects, increasing the acidity of the hydrogen cyanide H atom involved in the π H-bond. The longer HCN chains (n ≥ 3), however, can bend to form CH/N H-bonds with the Bz H atoms. These cyclic structures are found to be slightly more stable than their linear counterparts. For the nonlinear Bz(HCN)(3-4) and Bz(H(2)O)(2-4) complexes, an increase of the binding energy with the number of solvent molecules and a decrease of the IE of benzene, relative to the values for the Bz(HCN) and Bz(H(2)O) complexes, respectively, are observed. Although a strengthening of the CH/π and OH/π H-bonds, with increasing n, also takes place for the Bz(H(2)O)(2-4) and Bz(HCN)(3-4) nonlinear complexes, Bz proton donor, CH/O, and CH/N interactions are at the origin of this decrease. Thus CH/π and OH/π H-bonds lead to higher IEs of Bz, whereas the weaker CH/N and CH/O H-bond interactions have the opposite effect. The present results emphasize the importance of both aromatic XH/π (X = C, O) and CH/X (X = N, O) interactions for

  6. Studies on Metabolism of 1,4-Dioxane

    DTIC Science & Technology

    2010-03-01

    acid. This proposal was based upon chemical oxidation experiments on dioxane using nitric acid originally conducted by Fairley and coworkers ( Fairley ...S., Holler, J., Richter, P. and Stevens, y.-w. 1996. Health evaluation of 1,4-dioxane. Toxicol. Ind. Health 12, 1-43. Fairley , A., Linton, E. C

  7. Sunspot 1520 Releases Strong (X1.4) Solar Flare

    NASA Video Gallery

    This movie shows the sun July 10-12, ending with the X1.4 class flare on July 12, 2012. It was captured by NASA’s Solar Dynamics Observatory in the 131 Angstrom wavelength - a wavelength that is...

  8. 17 CFR 1.4 - Use of electronic signatures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Use of electronic signatures... REGULATIONS UNDER THE COMMODITY EXCHANGE ACT Definitions § 1.4 Use of electronic signatures. For purposes of... broker, a pool participant or a client of a commodity trading advisor, an electronic signature...

  9. ER-1422: Biodegradation of 1,4-Dioxane

    DTIC Science & Technology

    2007-08-01

    Pseudonocardia sp. strain K1 was used to hydrolyze diglycolic acid, the free radical generator phenazine methosulfate was included in the assay, as reported... phenazine methosulfate is not a physiologically relevant compound and can not be involved in 1,4-dioxane mineralization in vivo. III. D. Discussion of

  10. 14 CFR Sec. 1-4 - System of accounts coding.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... General Accounting Provisions Sec. 1-4 System of accounts coding. (a) A four digit control number is... digit code assigned to each profit and loss account denote a detailed area of financial activity or... sequentially within blocks, designating more general classifications of financial activity and...

  11. [Obtaining antibodies to 1,4-dihydropyridine calcium channel blockers].

    PubMed

    Burkin, A A; Murkin, M A

    2008-01-01

    Immunization of rabbits with amlodipine conjugated with horseradish peroxidase resulted in raising polyclonal antibodies that allowed group determination of 1,4-dihydropyridine calcium channel blockers in aqueous solutions by ELISA with a sensitivity of 0.1 to 1.0 ng/ml for amlodipine, felodipine, nifedipine, and isradipine.

  12. Proton dynamics in cancer

    PubMed Central

    2010-01-01

    Cancer remains a leading cause of death in the world today. Despite decades of research to identify novel therapeutic approaches, durable regressions of metastatic disease are still scanty and survival benefits often negligible. While the current strategy is mostly converging on target-therapies aimed at selectively affecting altered molecular pathways in tumor cells, evidences are in parallel pointing to cell metabolism as a potential Achilles' heel of cancer, to be disrupted for achieving therapeutic benefit. Critical differences in the metabolism of tumor versus normal cells, which include abnormal glycolysis, high lactic acid production, protons accumulation and reversed intra-extracellular pH gradients, make tumor site a hostile microenvironment where only cancer cells can proliferate and survive. Inhibiting these pathways by blocking proton pumps and transporters may deprive cancer cells of a key mechanism of detoxification and thus represent a novel strategy for a pleiotropic and multifaceted suppression of cancer cell growth. Research groups scattered all over the world have recently started to investigate various aspects of proton dynamics in cancer cells with quite encouraging preliminary results. The intent of unifying investigators involved in this research line led to the formation of the "International Society for Proton Dynamics in Cancer" (ISPDC) in January 2010. This is the manifesto of the newly formed society where both basic and clinical investigators are called to foster translational research and stimulate interdisciplinary collaboration for the development of more specific and less toxic therapeutic strategies based on proton dynamics in tumor cell biology. PMID:20550689

  13. High Temperature Protonic Conductors

    NASA Technical Reports Server (NTRS)

    Dynys, Fred; Berger, Marie-Helen; Sayir, Ali

    2007-01-01

    High Temperature Protonic Conductors (HTPC) with the perovskite structure are envisioned for electrochemical membrane applications such as H2 separation, H2 sensors and fuel cells. Successive membrane commercialization is dependent upon addressing issues with H2 permeation rate and environmental stability with CO2 and H2O. HTPC membranes are conventionally fabricated by solid-state sintering. Grain boundaries and the presence of intergranular second phases reduce the proton mobility by orders of magnitude than the bulk crystalline grain. To enhanced protonic mobility, alternative processing routes were evaluated. A laser melt modulation (LMM) process was utilized to fabricate bulk samples, while pulsed laser deposition (PLD) was utilized to fabricate thin film membranes . Sr3Ca(1+x)Nb(2-x)O9 and SrCe(1-x)Y(x)O3 bulk samples were fabricated by LMM. Thin film BaCe(0.85)Y(0.15)O3 membranes were fabricated by PLD on porous substrates. Electron microscopy with chemical mapping was done to characterize the resultant microstructures. High temperature protonic conduction was measured by impedance spectroscopy in wet air or H2 environments. The results demonstrate the advantage of thin film membranes to thick membranes but also reveal the negative impact of defects or nanoscale domains on protonic conductivity.

  14. INTEGRATED GASIFICATION COMBINED CYCLE PROJECT 2 MW FUEL CELL DEMONSTRATION

    SciTech Connect

    FuelCell Energy

    2005-05-16

    With about 50% of power generation in the United States derived from coal and projections indicating that coal will continue to be the primary fuel for power generation in the next two decades, the Department of Energy (DOE) Clean Coal Technology Demonstration Program (CCTDP) has been conducted since 1985 to develop innovative, environmentally friendly processes for the world energy market place. The 2 MW Fuel Cell Demonstration was part of the Kentucky Pioneer Energy (KPE) Integrated Gasification Combined Cycle (IGCC) project selected by DOE under Round Five of the Clean Coal Technology Demonstration Program. The participant in the CCTDP V Project was Kentucky Pioneer Energy for the IGCC plant. FuelCell Energy, Inc. (FCE), under subcontract to KPE, was responsible for the design, construction and operation of the 2 MW fuel cell power plant. Duke Fluor Daniel provided engineering design and procurement support for the balance-of-plant skids. Colt Engineering Corporation provided engineering design, fabrication and procurement of the syngas processing skids. Jacobs Applied Technology provided the fabrication of the fuel cell module vessels. Wabash River Energy Ltd (WREL) provided the test site. The 2 MW fuel cell power plant utilizes FuelCell Energy's Direct Fuel Cell (DFC) technology, which is based on the internally reforming carbonate fuel cell. This plant is capable of operating on coal-derived syngas as well as natural gas. Prior testing (1992) of a subscale 20 kW carbonate fuel cell stack at the Louisiana Gasification Technology Inc. (LGTI) site using the Dow/Destec gasification plant indicated that operation on coal derived gas provided normal performance and stable operation. Duke Fluor Daniel and FuelCell Energy developed a commercial plant design for the 2 MW fuel cell. The plant was designed to be modular, factory assembled and truck shippable to the site. Five balance-of-plant skids incorporating fuel processing, anode gas oxidation, heat recovery, water

  15. High-K, t{sub 1/2} = 1.4(1) ms, isomeric state in {sup 255}Lr

    SciTech Connect

    Hauschild, K.; Lopez-Martens, A.; Briancon, Ch.; Yeremin, A. V.; Belozerov, A. V.; Chelnokov, M. L.; Chepigin, V. I.; Gorshkov, V. A.; Kabachenko, A. P.; Malyshev, O. N.; Popeko, A. G.; Shutov, A. V.; Svirikhin, A. I.; Dorvaux, O.; Curien, D.; Gall, B.; Khalfallah, F.; Rousseau, M.; Rowley, N.; Stuttge, L.

    2008-08-15

    An isomeric state in {sup 255}Lr with a half-life of t{sub 1/2} = 1.4(1) ms and E{sub x}>720-keV has been observed for the first time using the GABRIELA setup at the focal plane of the VASSILISSA separator. Based on its K-forbiddeness, the configuration of the state is most probably formed by coupling the valence proton to a two quasiparticle neutron excitation. Possible three quasiparticle configurations are discussed.

  16. Physics at an upgraded proton driver at Fermilab

    SciTech Connect

    Steve Geer

    2004-07-28

    The accelerator-based particle physics program in the US is entering a period of transition. This is particularly true at Fermilab which for more than two decades has been the home of the Tevatron Proton-Antiproton Collider, the World's highest energy hadron collider. In a few years time the energy frontier will move to the LHC at CERN. Hence, if an accelerator-based program is to survive at Fermilab, it must evolve. Fermilab is fortunate in that, in addition to hosting the Tevatron Collider, the laboratory also hosts the US accelerator-based neutrino program. The recent discovery that neutrino flavors oscillate has opened a new exciting world for us to explore, and has created an opportunity for the Fermilab accelerator complex to continue to address the cutting-edge questions of particle physics beyond the Tevatron Collider era. The presently foreseen neutrino oscillation experiments at Fermilab (MiniBooNE [1] and MINOS [2]) will enable the laboratory to begin contributing to the Global oscillation physics program in the near future, and will help us better understand the basic parameters describing the oscillations. However, this is only a first step. To be able to pin down all of the oscillation parameters, and hopefully make new discoveries along the way, we will need high statistics experiments, which will require a very intense neutrino beam, and one or more very massive detectors. In particular we will require new MW-scale primary proton beams and perhaps ultimately a Neutrino Factory [3]. Plans to upgrade the Fermilab Proton Driver are presently being developed [4]. The upgrade project would replace the Fermilab Booster with a new 8 GeV accelerator with 0.5-2 MW beam power, a factor of 15-60 more than the current Booster. It would also make the modifications needed to the Fermilab Main Injector (MI) to upgrade it to simultaneously provide 120 GeV beams of 2 MW. This would enable a factor of 5-10 increase in neutrino beam intensities at the MI, while also

  17. Protons and how they are transported by proton pumps.

    PubMed

    Buch-Pedersen, M J; Pedersen, B P; Veierskov, B; Nissen, P; Palmgren, M G

    2009-01-01

    The very high mobility of protons in aqueous solutions demands special features of membrane proton transporters to sustain efficient yet regulated proton transport across biological membranes. By the use of the chemical energy of ATP, plasma-membrane-embedded ATPases extrude protons from cells of plants and fungi to generate electrochemical proton gradients. The recently published crystal structure of a plasma membrane H(+)-ATPase contributes to our knowledge about the mechanism of these essential enzymes. Taking the biochemical and structural data together, we are now able to describe the basic molecular components that allow the plasma membrane proton H(+)-ATPase to carry out proton transport against large membrane potentials. When divergent proton pumps such as the plasma membrane H(+)-ATPase, bacteriorhodopsin, and F(O)F(1) ATP synthase are compared, unifying mechanistic premises for biological proton pumps emerge. Most notably, the minimal pumping apparatus of all pumps consists of a central proton acceptor/donor, a positively charged residue to control pK(a) changes of the proton acceptor/donor, and bound water molecules to facilitate rapid proton transport along proton wires.

  18. 300 MW combined-cycle plant with integrated coal gasification

    SciTech Connect

    Kehlhofer, R.H.

    1984-09-01

    The main obstacle to further expansion of the combined cycle principle is its lack of fuel flexibility. To this day, gas turbines are still limited to gaseous or liquid fuels. This paper shows a viable way to add a cheap solid fuel, coal, to the list. The plant system in question is a 2 X 150 MW combined-cycle plant of BBC Brown Boveri with integrated coal gasification plant of British Gas/Lurgi. The main point of interest is that All the individual components of the power plant described in this paper have proven their worth commercially. It is therefore not a pilot plant but a viable commercial proposition.

  19. 1.5 MW RF Load for ITER

    SciTech Connect

    Ives, Robert Lawrence; Marsden, David; Collins, George; Karimov, Rasul; Mizuhara, Max; Neilson, Jeffrey

    2016-09-01

    Calabazas Creek Research, Inc. developed a 1.5 MW RF load for the ITER fusion research facility currently under construction in France. This program leveraged technology developed in two previous SBIR programs that successfully developed high power RF loads for fusion research applications. This program specifically focused on modifications required by revised technical performance, materials, and assembly specification for ITER. This program implemented an innovative approach to actively distribute the RF power inside the load to avoid excessive heating or arcing associated with constructive interference. The new design implemented materials and assembly changes required to meet specifications. Critical components were built and successfully tested during the program.

  20. 40 CFR 721.10678 - 1,4-Cyclohexanedicarboxylic acid, 1,4-dimethyl ester, hydrogenolysis products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-dimethyl ester, hydrogenolysis products. 721.10678 Section 721.10678 Protection of Environment..., 1,4-dimethyl ester, hydrogenolysis products. (a) Chemical substance and significant new uses subject... ester, hydrogenolysis products (PMN P-13-10; CAS No. 1373220-73-5) is subject to reporting under...

  1. The physics of proton therapy.

    PubMed

    Newhauser, Wayne D; Zhang, Rui

    2015-04-21

    The physics of proton therapy has advanced considerably since it was proposed in 1946. Today analytical equations and numerical simulation methods are available to predict and characterize many aspects of proton therapy. This article reviews the basic aspects of the physics of proton therapy, including proton interaction mechanisms, proton transport calculations, the determination of dose from therapeutic and stray radiations, and shielding design. The article discusses underlying processes as well as selected practical experimental and theoretical methods. We conclude by briefly speculating on possible future areas of research of relevance to the physics of proton therapy.

  2. The physics of proton therapy

    PubMed Central

    Newhauser, Wayne D; Zhang, Rui

    2015-01-01

    The physics of proton therapy has advanced considerably since it was proposed in 1946. Today analytical equations and numerical simulation methods are available to predict and characterize many aspects of proton therapy. This article reviews the basic aspects of the physics of proton therapy, including proton interaction mechanisms, proton transport calculations, the determination of dose from therapeutic and stray radiations, and shielding design. The article discusses underlying processes as well as selected practical experimental and theoretical methods. We conclude by briefly speculating on possible future areas of research of relevance to the physics of proton therapy. PMID:25803097

  3. Ambiphilic boron in 1,4,2,5-diazadiborinine

    PubMed Central

    Wang, Baolin; Li, Yongxin; Ganguly, Rakesh; Hirao, Hajime; Kinjo, Rei

    2016-01-01

    Boranes have long been known as the archetypal Lewis acids owing to an empty p-orbital on the boron centre. Meanwhile, Lewis basic tricoordinate boranes have been developed in recent years. Here we report the synthesis of an annulated 1,4,2,5-diazadiborinine derivative featuring boron atoms that exhibit both Lewis acidic and basic properties. Experimental and computational studies confirmed that two boron atoms in this molecule are spectroscopically equivalent. Nevertheless, this molecule cleaves C–O, B–H, Si–H and P–H bonds heterolytically, and readily undergoes [4+2] cycloaddition reaction with non-activated unsaturated bonds such as C=O, C=C, C≡C and C≡N bonds. The result, thus, indicates that the indistinguishable boron atoms in 1,4,2,5-diazadiborinine act as both nucleophilic and electrophilic centres, demonstrating ambiphilic nature. PMID:27279265

  4. Synthesis and pharmacological activity of 1,4-benzodiazepine derivatives.

    PubMed

    Osman, A N; el-Gendy, A A; Omar, R H; Wagdy, L; Omar, A H

    2002-01-01

    2-Aminobenzamides (3a-g) were prepared starting with isatoic anhydride. These compounds reacted with chloroacetic acid to give (4a-g), which were cyclized by dicyclohexylcorbodiimide to afford (5a-g). The preliminary pharmacological screening revealed that some of the new 2H-1,4-benzodiazepin-3,5(1H,4H)-dione derivatives (5) exhibited CNS-depressant and anticonvulsant activities.

  5. 15N NMR of 1,4-dihydropyridine derivatives.

    PubMed

    Goba, Inguna; Liepinsh, Edvards

    2013-07-01

    In this article, we describe the characteristic (15)N and (1)HN NMR chemical shifts and (1)J((15)N-(1)H) coupling constants of various symmetrically and unsymmetrically substituted 1,4-dihydropyridine derivatives. The NMR chemical shifts and coupling constants are discussed in terms of their relationship to structural features such as character and position of the substituent in heterocycle, N-alkyl substitution, nitrogen lone pair delocalization within the conjugated system, and steric effects.

  6. Proton irradiation and endometriosis

    SciTech Connect

    Wood, D.H.; Yochmowitz, M.G.; Salmon, Y.L.; Eason, R.L.; Boster, R.A.

    1983-08-01

    It was found that female rhesus monkeys given single total-body exposures of protons of varying energies developed endometriosis at a frequency significantly higher than that of nonirradiated animals of the same age. The minimum latency period was determined to be 7 years after the proton exposure. The doses and energies of the radiation received by the experimental animals were within the range that could be received by an aircrew member in near-earth orbit during a random solar flare event. It is concluded that endometriosis should be a consideration in assessing the risk of delayed radiation effects in female crew members. 15 references.

  7. Synthesis of 1,4-dihydropyridines under solvent free conditions and investigation of their photo physical properties

    NASA Astrophysics Data System (ADS)

    Ramchander, J.; Raju, Gajula; Rameshwar, N.; Reddy, T. Sheshashena; Reddy, A. Ram

    2012-01-01

    Synthesis of five 4-aryl substituted 1,4-dihydropyridines was developed following condensation of multi component reaction strategy using yttrium triflate as a catalyst. The absorption and fluorescence properties of structurally related 4-aryl 1,4-dihydropyridines in different solvents of varied polarities was investigated. The absorption maxima of these compounds follow no order of solvent polarity and nature of substitution. The spectral characteristics are solvent and compound specific. Fluorophores with electron withdrawing group have larger fluorescence quantum yields and greater solvatochromism than the compounds with electron donating groups. Protic solvents yielded higher fluorescence quantum efficiency. The chemical shift of the proton attached to C-4 and the carbonyl stretching frequency of bis acetyl groups at 3 and 5-positions exhibited a linear relationship with Hammett's para substituent constants while no such relationship exists between the latter and electronic absorption maxima, fluorescence emission maxima, fluorescence quantum efficiency and Stokes shift.

  8. Synthesis of 1,4-dihydropyridines under solvent free conditions and investigation of their photo physical properties.

    PubMed

    Ramchander, J; Raju, Gajula; Rameshwar, N; Reddy, T Sheshashena; Reddy, A Ram

    2012-01-01

    Synthesis of five 4-aryl substituted 1,4-dihydropyridines was developed following condensation of multi component reaction strategy using yttrium triflate as a catalyst. The absorption and fluorescence properties of structurally related 4-aryl 1,4-dihydropyridines in different solvents of varied polarities was investigated. The absorption maxima of these compounds follow no order of solvent polarity and nature of substitution. The spectral characteristics are solvent and compound specific. Fluorophores with electron withdrawing group have larger fluorescence quantum yields and greater solvatochromism than the compounds with electron donating groups. Protic solvents yielded higher fluorescence quantum efficiency. The chemical shift of the proton attached to C-4 and the carbonyl stretching frequency of bis acetyl groups at 3 and 5-positions exhibited a linear relationship with Hammett's para substituent constants while no such relationship exists between the latter and electronic absorption maxima, fluorescence emission maxima, fluorescence quantum efficiency and Stokes shift.

  9. GHB, GBL and 1,4-BD addiction.

    PubMed

    Brunt, Tibor M; van Amsterdam, Jan G C; van den Brink, Wim

    2014-01-01

    A growing body of evidence shows that gamma-hydroxybutyric acid (GHB) is an addictive substance. Its precursors gammabutyrolactone (GBL) and 1,4-butanediol (1,4-BD) show the same properties and may pose even more risks due to different pharmacokinetics. There are indications that problematic GHB use is increasing in the European Union. This review investigates the existing literature on the neurochemistry of GHB and its precursors, their acute toxicity, addiction potential and withdrawal, the proposed molecular mechanism underlying addiction and the treatment of withdrawal and addiction. Current evidence shows that GHB and its precursors are highly addictive, both in humans and animals, probably through a GABAB receptor related mechanism. Severity of withdrawal symptoms can be considered as a medical emergency. Recent studies suggest that benzodiazepines are not very effective, showing a high treatment resistance, whereas detoxification with pharmaceutical GHB proved to be successful. However, relapse in GHB use is frequent and more research is warranted on relapse prevention. This might aid medical practitioners in the field and improve general understanding of the severity of addiction to GHB, GBL and 1,4-BD.

  10. Direct Aminolysis of Ethoxycarbonylmethyl 1,4-Dihydropyridine-3-carboxylates.

    PubMed

    Vigante, Brigita; Rucins, Martins; Plotniece, Aiva; Pajuste, Karlis; Luntena, Iveta; Cekavicus, Brigita; Bisenieks, Egils; Smits, Rufus; Duburs, Gunars; Sobolev, Arkadij

    2015-11-12

    The ethoxycarbonylmethyl esters of 1,4-dihydropyridines were directly converted into carbamoylmethyl esters in the presence of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) in good to excellent yields under mild conditions. The use of TBD is crucial for the successful aminolysis of ethoxycarbonylmethyl ester of 1,4-dihydropyridines with secondary amines as without it the reaction does not proceed at all. The aminolysis reaction proceeded regioselectively, as the alkyl ester conjugated with the 1,4-dihydropyridine cycle was not involved in the reaction. Screening of other N-containing bases, such as triethylamine (TEA), pyridine, 4-(N,N-dimethylamino)pyridine (DMAP), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), imidazole, tetramethyl guanidine (TMG) and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD) as catalysts revealed no activity in the studied reaction.

  11. Proton-Proton Scattering at 105 Mev and 75 Mev

    DOE R&D Accomplishments Database

    Birge, R. W.; Kruse, U. E.; Ramsey, N. F.

    1951-01-31

    The scattering of protons by protons provides an important method for studying the nature of nuclear forces. Recent proton-proton scattering experiments at energies as high as thirty Mev{sup 1} have failed to show any appreciable contribution to the cross section from higher angular momentum states, but it is necessary to bring in tensor forces to explain the magnitude of the observed cross section.

  12. Progress in Increasing Gyrotron Output Power Beyond 1 MW

    NASA Astrophysics Data System (ADS)

    Felch, K.; Blank, M.; Borchard, P.; Cahalan, P.; Cauffman, S.; Jory, H.

    2009-04-01

    A 95 GHz, multi-megawatt continuous-wave (CW) gyrotron oscillator is currently under development at CPI. The gyrotron consists of a single-anode magnetron injection gun designed to operate at 75 A and 90 kV, a TE22,6 mode cylindrical interaction cavity, an internal mode converter to transform the TE22,6 mode to a Gausssian beam, an edge-cooled CVD diamond output window, and a single-stage depressed collector fabricated from a strengthened copper alloy. During the initial experimental campaign, carried out in the Summer of 2007, peak output power levels up to 1 MW at 40 A beam current were demonstrated at pulse lengths up to 5 ms. In addition, pulses up to 15 s in duration at 25 A beam current, the long-pulse limit of the CPI test stand, and 630 kW peak output power were achieved. In the Fall of 2007, modifications to the CPI test stand were made to allow for short-pulse operation up to 75 A. A second test campaign, aimed at demonstrating peak output power in excess of 1 MW, is planned for early in 2008.

  13. Initial Testing of a 140 GHz 1 MW Gyrotron

    NASA Astrophysics Data System (ADS)

    Cauffman, Stephen; Felch, Kevin; Blank, Monica; Borchard, Philipp; Cahalan, Pat; Chu, Sam; Jory, Howard

    2001-10-01

    CPI has completed the fabrication of a 140 GHz 1 MW CW gyrotron to be used on the W7-X stellarator at IPP Greifswald. Testing of the initial build of this gyrotron had just begun when this abstract was prepared, and was expected to finish in September, at which time a planned rebuild of the device was scheduled to begin. This poster will summarize the gyrotron design, present results of initial testing, and outline any design changes planned as a consequence of these results. This gyrotron's design employs a number of advanced features, including a diode electron gun for simplified operation, a single-stage depressed collector to enhance overall efficiency, a CVD diamond output window, an internal mode converter that converts the excited TE28,7 cavity mode to a Gaussian output beam, and a high-voltage layout that locates all external high voltage below the superconducting magnet system without requiring an oil tank for insulation. Similar features are being used for an 84 GHz 500 kW system being built for the KSTAR tokamak program and for a 110 GHz 1.5 MW system being designed in collaboration with MIT, UMd, UW, GA, and Calabazas Creek Research with funding provided by DOE.

  14. Proton irradiation effects on beryllium – A macroscopic assessment

    SciTech Connect

    Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; Camino, Fernando

    2016-07-01

    Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting its lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This study focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.

  15. Proton irradiation effects on beryllium - A macroscopic assessment

    NASA Astrophysics Data System (ADS)

    Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; Camino, Fernando

    2016-10-01

    Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting its lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This paper focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.

  16. Proton irradiation effects on beryllium – A macroscopic assessment

    DOE PAGES

    Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; ...

    2016-07-01

    Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting itsmore » lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This study focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.« less

  17. The Search for Proton Decay.

    ERIC Educational Resources Information Center

    Marshak, Marvin L.

    1984-01-01

    Provides the rationale for and examples of experiments designed to test the stability of protons and bound neutrons. Also considers the unification question, cosmological implications, current and future detectors, and current status of knowledge on proton decay. (JN)

  18. Three new defined proton affinities for polybasic molecules in the gas-phase: Proton microaffinity, proton macroaffinity and proton overallaffinity

    NASA Astrophysics Data System (ADS)

    Salehzadeh, Sadegh; Bayat, Mehdi

    2006-08-01

    A theoretical study on complete protonation of a series of tetrabasic molecules with general formula N[(CH 2) nNH 2][(CH 2) mNH 2][(CH 2) pNH 2] (tren, pee, ppe, tpt, epb and ppb) is reported. For first time, three kinds of gas-phase proton affinities for each polybasic molecule are defined as: 'proton microaffinity (PA n, i)', 'proton macroaffinity (PA)' and 'proton overall affinity ( PA)'. The variations of calculated logPA in the series of these molecules is very similar to that of their measured log Kn. There is also a good correlation between the calculated gas-phase proton macroaffinities and proton overallaffinities with corresponding equilibrium macroconstants and overall protonation constants in solution.

  19. Proton therapy in clinical practice

    PubMed Central

    Liu, Hui; Chang, Joe Y.

    2011-01-01

    Radiation dose escalation and acceleration improves local control but also increases toxicity. Proton radiation is an emerging therapy for localized cancers that is being sought with increasing frequency by patients. Compared with photon therapy, proton therapy spares more critical structures due to its unique physics. The physical properties of a proton beam make it ideal for clinical applications. By modulating the Bragg peak of protons in energy and time, a conformal radiation dose with or without intensity modulation can be delivered to the target while sparing the surrounding normal tissues. Thus, proton therapy is ideal when organ preservation is a priority. However, protons are more sensitive to organ motion and anatomy changes compared with photons. In this article, we review practical issues of proton therapy, describe its image-guided treatment planning and delivery, discuss clinical outcome for cancer patients, and suggest challenges and the future development of proton therapy. PMID:21527064

  20. High Power Proton Facilities

    NASA Astrophysics Data System (ADS)

    Nagaitsev, Sergei

    2015-04-01

    This presentation will provide an overview of the capabilities and challenges of high intensity proton accelerators, such as J-PARC, Fermilab MI, SNS, ISIS, PSI, ESS (in the future) and others. The presentation will focus on lessons learned, new concepts, beam loss mechanisms and methods to mitigate them.

  1. Protons Trigger Mitochondrial Flashes.

    PubMed

    Wang, Xianhua; Zhang, Xing; Huang, Zhanglong; Wu, Di; Liu, Beibei; Zhang, Rufeng; Yin, Rongkang; Hou, Tingting; Jian, Chongshu; Xu, Jiejia; Zhao, Yan; Wang, Yanru; Gao, Feng; Cheng, Heping

    2016-07-26

    Emerging evidence indicates that mitochondrial flashes (mitoflashes) are highly conserved elemental mitochondrial signaling events. However, which signal controls their ignition and how they are integrated with other mitochondrial signals and functions remain elusive. In this study, we aimed to further delineate the signal components of the mitoflash and determine the mitoflash trigger mechanism. Using multiple biosensors and chemical probes as well as label-free autofluorescence, we found that the mitoflash reflects chemical and electrical excitation at the single-organelle level, comprising bursting superoxide production, oxidative redox shift, and matrix alkalinization as well as transient membrane depolarization. Both electroneutral H(+)/K(+) or H(+)/Na(+) antiport and matrix proton uncaging elicited immediate and robust mitoflash responses over a broad dynamic range in cardiomyocytes and HeLa cells. However, charge-uncompensated proton transport, which depolarizes mitochondria, caused the opposite effect, and steady matrix acidification mildly inhibited mitoflashes. Based on a numerical simulation, we estimated a mean proton lifetime of 1.42 ns and diffusion distance of 2.06 nm in the matrix. We conclude that nanodomain protons act as a novel, to our knowledge, trigger of mitoflashes in energized mitochondria. This finding suggests that mitoflash genesis is functionally and mechanistically integrated with mitochondrial energy metabolism.

  2. All-solid-state proton battery using gel polymer electrolyte

    SciTech Connect

    Mishra, Kuldeep; Pundir, S. S.; Rai, D. K.

    2014-04-24

    A proton conducting gel polymer electrolyte system; PMMA+NH{sub 4}SCN+EC/PC, has been prepared. The highest ionic conductivity obtained from the system is 2.5 × 10−4 S cm{sup −1}. The optimized composition of the gel electrolyte has been used to fabricate a proton battery with Zn/ZnSO{sub 4}⋅7H{sub 2}O anode and MnO{sub 2} cathode. The open circuit voltage of the battery is 1.4 V and the highest energy density is 5.7 W h kg−1 for low current drain.

  3. Intensity modulated proton therapy

    PubMed Central

    Grassberger, C

    2015-01-01

    Intensity modulated proton therapy (IMPT) implies the electromagnetic spatial control of well-circumscribed “pencil beams” of protons of variable energy and intensity. Proton pencil beams take advantage of the charged-particle Bragg peak—the characteristic peak of dose at the end of range—combined with the modulation of pencil beam variables to create target-local modulations in dose that achieves the dose objectives. IMPT improves on X-ray intensity modulated beams (intensity modulated radiotherapy or volumetric modulated arc therapy) with dose modulation along the beam axis as well as lateral, in-field, dose modulation. The clinical practice of IMPT further improves the healthy tissue vs target dose differential in comparison with X-rays and thus allows increased target dose with dose reduction elsewhere. In addition, heavy-charged-particle beams allow for the modulation of biological effects, which is of active interest in combination with dose “painting” within a target. The clinical utilization of IMPT is actively pursued but technical, physical and clinical questions remain. Technical questions pertain to control processes for manipulating pencil beams from the creation of the proton beam to delivery within the patient within the accuracy requirement. Physical questions pertain to the interplay between the proton penetration and variations between planned and actual patient anatomical representation and the intrinsic uncertainty in tissue stopping powers (the measure of energy loss per unit distance). Clinical questions remain concerning the impact and management of the technical and physical questions within the context of the daily treatment delivery, the clinical benefit of IMPT and the biological response differential compared with X-rays against which clinical benefit will be judged. It is expected that IMPT will replace other modes of proton field delivery. Proton radiotherapy, since its first practice 50 years ago, always required the

  4. Proton radiography for clinical applications

    NASA Astrophysics Data System (ADS)

    Talamonti, C.; Reggioli, V.; Bruzzi, M.; Bucciolini, M.; Civinini, C.; Marrazzo, L.; Menichelli, D.; Pallotta, S.; Randazzo, N.; Sipala, V.; Cirrone, G. A. P.; Petterson, M.; Blumenkrantz, N.; Feldt, J.; Heimann, J.; Lucia, D.; Seiden, A.; Williams, D. C.; Sadrozinski, H. F.-W.; Bashkirov, V.; Schulte, R.

    2010-01-01

    Proton imaging is not yet applied as a clinical routine, although its advantages have been demonstrated. In the context of quality assurance in proton therapy, proton images can be used to verify the correct positioning of the patient and to control the range of protons. Proton computed tomography (pCT) is a 3D imaging method appropriate for planning and verification of proton radiation treatments, because it allows evaluating the distributions of proton stopping power within the tissues and can be directly utilized when the patient is in the actual treatment position. The aim of the PRoton IMAging experiment, supported by INFN, and the PRIN 2006 project, supported by MIUR, is to realize a proton computed radiography (pCR) prototype for reconstruction of proton images from a single projection in order to validate the technique with pre-clinical studies and, eventually, to conceive the configuration of a complete pCT system. A preliminary experiment performed at the 250 MeV proton synchrotron of Loma Linda University Medical Center (LLUMC) allowed acquisition of experimental data before the completion of PRIMA project's prototype. In this paper, the results of the LLUMC experiment are reported and the reconstruction of proton images of two phantoms is discussed.

  5. Photoluminescent carbon dots from 1,4-addition polymers.

    PubMed

    Jiang, Zhiqiang; Nolan, Andrew; Walton, Jeffrey G A; Lilienkampf, Annamaria; Zhang, Rong; Bradley, Mark

    2014-08-25

    Photoluminescent carbon dots were synthesised directly by thermopyrolysis of 1,4-addition polymers, allowing precise control of their properties. The effect of polymer composition on the properties of the carbon dots was investigated by TEM, IR, XPS, elemental analysis and fluorescence analysis, with carbon dots synthesised from nitrogen-containing polymers showing the highest fluorescence. The carbon dots with high nitrogen content were observed to have strong fluorescence in the visible region, and culture with cells showed that the carbon dots were non-cytotoxic and readily taken up by three different cell lines.

  6. Experimental study of a 1 MW, 170 GHz gyrotron oscillator

    NASA Astrophysics Data System (ADS)

    Kimura, Takuji

    A detailed experimental study is presented of a 1 MW, 170 GHz gyrotron oscillator whose design is consistent with the ECH requirements of the International Thermonuclear Experimental Reactor (ITER) for bulk heating and current drive. This work is the first to demonstrate that megawatt power level at 170 GHz can be achieved in a gyrotron with high efficiency for plasma heating applications. Maximum output power of 1.5 MW is obtained at 170.1 GHz in 85 kV, 50A operation for an efficiency of 35%. Although the experiment at MIT is conducted with short pulses (3 μs), the gyrotron is designed to be suitable for development by industry for continuous wave operation. The peak ohmic loss on the cavity wall for 1 MW of output power is calculated to be 2.3 kW/cm2, which can be handled using present cooling technology. Mode competition problems in a highly over-moded cavity are studied to maximize the efficiency. Various aspects of electron gun design are examined to obtain high quality electron beams with very low velocity spread. A triode magnetron injection gun is designed using the EGUN simulation code. A total perpendicular velocity spread of less than 8% is realized by designing a low- sensitivity, non-adiabatic gun. The RF power is generated in a short tapered cavity with an iris step. The operating mode is the TE28,8,1 mode. A mode converter is designed to convert the RF output to a Gaussian beam. Power and efficiency are measured in the design TE28,8,1 mode at 170.1 GHz as well as the TE27,8,1 mode at 166.6 GHz and TE29,8,1 mode at 173.5 GHz. Efficiencies between 34%-36% are consistently obtained over a wide range of operating parameters. These efficiencies agree with the highest values predicted by the multimode simulations. The startup scenario is investigated and observed to agree with the linear theory. The measured beam velocity ratio is consistent with EGUN simulation. Interception of reflected beam by the mod-anode is measured as a function of velocity ratio

  7. 15 MW HArdware-in-the-loop Grid Simulation Project

    SciTech Connect

    Rigas, Nikolaos; Fox, John Curtiss; Collins, Randy; Tuten, James; Salem, Thomas; McKinney, Mark; Hadidi, Ramtin; Gislason, Benjamin; Boessneck, Eric; Leonard, Jesse

    2014-10-31

    The 15MW Hardware-in-the-loop (HIL) Grid Simulator project was to (1) design, (2) construct and (3) commission a state-of-the-art grid integration testing facility for testing of multi-megawatt devices through a ‘shared facility’ model open to all innovators to promote the rapid introduction of new technology in the energy market to lower the cost of energy delivered. The 15 MW HIL Grid Simulator project now serves as the cornerstone of the Duke Energy Electric Grid Research, Innovation and Development (eGRID) Center. This project leveraged the 24 kV utility interconnection and electrical infrastructure of the US DOE EERE funded WTDTF project at the Clemson University Restoration Institute in North Charleston, SC. Additionally, the project has spurred interest from other technology sectors, including large PV inverter and energy storage testing and several leading edge research proposals dealing with smart grid technologies, grid modernization and grid cyber security. The key components of the project are the power amplifier units capable of providing up to 20MW of defined power to the research grid. The project has also developed a one of a kind solution to performing fault ride-through testing by combining a reactive divider network and a large power converter into a hybrid method. This unique hybrid method of performing fault ride-through analysis will allow for the research team at the eGRID Center to investigate the complex differences between the alternative methods of performing fault ride-through evaluations and will ultimately further the science behind this testing. With the final goal of being able to perform HIL experiments and demonstration projects, the eGRID team undertook a significant challenge with respect to developing a control system that is capable of communicating with several different pieces of equipment with different communication protocols in real-time. The eGRID team developed a custom fiber optical network that is based upon FPGA

  8. Exploring universality of transversity in proton-proton collisions

    NASA Astrophysics Data System (ADS)

    Radici, Marco; Ricci, Alessandro M.; Bacchetta, Alessandro; Mukherjee, Asmita

    2016-08-01

    We consider the azimuthal correlations of charged hadron pairs with large total transverse momentum and small relative momentum, produced in proton-proton collisions with one transversely polarized proton. One of these correlations directly probes the chiral-odd transversity parton distribution in connection with a chiral-odd interference fragmentation function. We present predictions for this observable based on previous extractions of transversity (from charged pion pair production in semi-inclusive deep-inelastic scattering) and of the interference fragmentation function (from the production of back-to-back charged pion pairs in electron-positron annihilations). All analyses are performed in the framework of collinear factorization. We compare our predictions to the recent data on proton-proton collisions released by the STAR Collaboration at RHIC, and we find them reasonably compatible. This comparison confirms for the first time the predicted role of transversity in proton-proton collisions, and it allows us to test its universality.

  9. Proton radiography and tomography with application to proton therapy.

    PubMed

    Poludniowski, G; Allinson, N M; Evans, P M

    2015-09-01

    Proton radiography and tomography have long promised benefit for proton therapy. Their first suggestion was in the early 1960s and the first published proton radiographs and CT images appeared in the late 1960s and 1970s, respectively. More than just providing anatomical images, proton transmission imaging provides the potential for the more accurate estimation of stopping-power ratio inside a patient and hence improved treatment planning and verification. With the recent explosion in growth of clinical proton therapy facilities, the time is perhaps ripe for the imaging modality to come to the fore. Yet many technical challenges remain to be solved before proton CT scanners become commonplace in the clinic. Research and development in this field is currently more active than at any time with several prototype designs emerging. This review introduces the principles of proton radiography and tomography, their historical developments, the raft of modern prototype systems and the primary design issues.

  10. Proton radiography and tomography with application to proton therapy

    PubMed Central

    Allinson, N M; Evans, P M

    2015-01-01

    Proton radiography and tomography have long promised benefit for proton therapy. Their first suggestion was in the early 1960s and the first published proton radiographs and CT images appeared in the late 1960s and 1970s, respectively. More than just providing anatomical images, proton transmission imaging provides the potential for the more accurate estimation of stopping-power ratio inside a patient and hence improved treatment planning and verification. With the recent explosion in growth of clinical proton therapy facilities, the time is perhaps ripe for the imaging modality to come to the fore. Yet many technical challenges remain to be solved before proton CT scanners become commonplace in the clinic. Research and development in this field is currently more active than at any time with several prototype designs emerging. This review introduces the principles of proton radiography and tomography, their historical developments, the raft of modern prototype systems and the primary design issues. PMID:26043157

  11. Recent performance and ignition tests of the pulsed SNS H- source for 1-MW neutron production

    NASA Astrophysics Data System (ADS)

    Stockli, Martin P.; Han, B. X.; Murray, S. N.; Pennisi, T. R.; Piller, C.; Santana, M.; Welton, R. F.

    2015-04-01

    After acquiring several reliable spare targets, SNS ramped the beam power from 850 kW to 1.4 MW, which required an increase in H- beam pulse length from 0.88 to 1.0 ms at 60 Hz. This increase initially produced slow 2-MHz power ramp-ups and, after several weeks of uninterrupted operation, it produced plasma outages every time the pulse length was raised above ˜0.95 ms. Similar outages were previously observed towards the end of long service cycles, which were believed to indicate that the breakdown voltage of the high purity hydrogen started to exceed the induced electric fields. In 2011 the RF was reconfigured to start with 10 cycles of 1.96 MHz, which yielded the shortest H- beam rise times and apparently eliminated those plasma outages. The new, pulse-length dependent outages were eliminated by increasing the initial frequency to 1.985 MHz. However, careful frequency studies are unable to justify this frequency. In addition, the paper discusses the issues and solutions for the electron-dump voltage, which starts to sag and become unstable after several weeks of high current operation. At the request of the authors and the Proceedings Editor this article has been updated to include References 3-13, which were present in the author's original submission but were lost during manuscript processing in the Proceedings Editor's office. The updated article was published on 5 May 2015.

  12. Recent Performance and Ignition Tests of the pulsed SNS H- Source for 1-MW Neutron Production

    SciTech Connect

    Stockli, Martin P; Han, Baoxi; Murray, Jr, S N; Pennisi, Terry R; Piller, Chip; Santana, Manuel; Welton, Robert F

    2015-01-01

    After acquiring several reliable spare targets, SNS ramped the beam power from 850 kW to 1.4 MW, which required an increase in H- beam pulse length from 0.88 to 1.0 ms at 60 Hz. This increase initially produced slow 2-MHz power ramp-ups and, after several weeks of uninterrupted operation, it produced plasma outages every time the pulse length was raised above ~0.95 ms. Similar outages were previously observed towards the end of long service cycles, which were believed to indicate that the breakdown voltage of the high purity hydrogen started to exceed the induced electric fields. In 2011 the RF was reconfigured to start with 10 cycles of 1.96 MHz, which yielded the shortest H- beam rise times and apparently eliminated those plasma outages. The new, pulse-length dependent outages were eliminated by increasing the initial frequency to 1.985 MHz. However, careful frequency studies are unable to justify this frequency. In addition, the paper discusses the issues and solutions for the electron-dump voltage, which starts to sag and become unstable after several weeks of high current operation.

  13. The proton affinities of saturated and unsaturated heterocyclic molecules

    NASA Astrophysics Data System (ADS)

    Kabli, Samira; van Beelen, Eric S. E.; Ingemann, Steen; Henriksen, Lars; Hammerum, Steen

    2006-03-01

    The proton affinities derived from G3-calculations of 23 five-membered ring heteroaromatic molecules agree well with the experimentally determined values available in the literature. The calculated local proton affinities show that the principal site of protonation of the heteroaromatic compounds examined is an atom of the ring, carbon when there is only one heteroatom in the ring, and nitrogen where there are two or more heteroatoms. The experimental proton affinities of non-aromatic cyclic ethers, amines and thioethers are also in excellent agreement with the calculated values, with two exceptions (oxetane, N-methylazetidine). The literature proton affinities of the four simple cyclic ethers, oxetane, tetrahydrofuran, tetrahydropyran and oxepane were confirmed by Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry, in order to examine the disagreement between the values predicted by extrapolation or additivity for tetrahydrofuran and tetrahydropyran and those determined by experiment and by calculation. The proton affinity differences between the pairs tetrahydropyran/1,4-dioxane, piperidine/morpholine and related compounds show that introduction of an additional oxygen atom in the ring considerably lowers the basicity.

  14. Reactivity initiated accident test series Test RIA 1-4

    SciTech Connect

    Martinson, Z.R.; El-Genk, M.S.; Fukuda, S.K.; LaPointe, R.E.; Osetek, D.J.

    1980-05-01

    The Reactivity Initiated Accident (RIA) Test RIA 1-4, the first 9-rod fuel rod bundle RIA Test to be performed at BWR hot startup conditions, was completed on April 16, 1980. The test was performed in the Power Burst Facility (PBF). Objective for Test RIA 1-4 was to provide information regarding loss-of-coolable fuel rod geometry following a RIA event for a peak fuel enthalpy equivalent to the present licensing criteria of 280 cal/g. The most severe RIA is the postulated Boiling Water Reactor (BWR) control rod drop during reactor startup. Therefore the test was conducted at BWR hot startup coolant conditions (538 K, 6.45 MPa, 0.8 1/sec). The test sequence began with steady power operation to condition the fuel, establish a short-lived fission product inventory, and calibrate the calorimetric measurements and core power chambers, neutron flux and gamma flux detectors. The test train was removed from the in-pile tube (IPT) to replace one of the fuel rods with a nominally identical irradiated rod and twelve flux wire monitors. A 2.8 ms period power burst was then performed. Coolant flow measurements were made before and after the power burst to characterize the flow blockage that occurred as a result of fuel rod failure.

  15. 1. 4 gigahertz luminosity function and its evolution

    SciTech Connect

    Condon, J. J.

    1989-03-01

    The local luminosity function was determined at v = 1.4 GHz from radio observations of two low-redshift galaxy samples: (1) spiral and irregular galaxies with apparent blue magnitudes and declinations and (2) galaxies of all morphologies with blue angular diameters of 1.0 arcmin or greater in the declination range between -2.5 deg and +82 deg. Separate luminosity functions for the radio source populations powered by 'starbursts' and 'monsters' were obtained from the latter sample. The amount of evolution required for the local luminosity function to account for the faint sources is discussed. The cosmological evolution of extragalactic radio sources appears to be so strong at all observed luminosities that the local luminosity function and counts of all sources between S of roughly 10 micro-Jy and S of roughly 10 Jy at v = 1.4 GHz can be matched with a model in which most sources are confined to a hollow shell with z of roughly 0.8. 36 refs.

  16. Design of an Aeroelastically Tailored 10 MW Wind Turbine Rotor

    NASA Astrophysics Data System (ADS)

    Zahle, Frederik; Tibaldi, Carlo; Pavese, Christian; McWilliam, Michael K.; Blasques, Jose P. A. A.; Hansen, Morten H.

    2016-09-01

    This work presents an integrated multidisciplinary wind turbine optimization framework utilizing state-of-the-art aeroelastic and strutural tools, capable of simultaneous design of the outer geometry and internal structure of the blade. The framework is utilized to design a 10 MW rotor constrained not to exceed the design loads of an existing reference wind turbine. The results show that through combined geometric tailoring of the internal structure and aerodynamic shape of the blade it is possible to achieve significant passive load alleviation that allows for a 9% longer blade with an increase in AEP of 8.7%, without increasing blade mass and without significant increases in ultimate and fatigue loads on the hub and tower.

  17. 120 MW, 800 MHz Magnicon for a Future Muon Collider

    SciTech Connect

    Jay L. Hirshfield

    2005-12-15

    Development of a pulsed magnicon at 800 MHz was carried out for the muon collider application, based on experience with similar amplifiers in the frequency range between 915 MHz and 34.3 GHz. Numerical simulations using proven computer codes were employed for the conceptual design, while established design technologies were incorporated into the engineering design. A cohesive design for the 800 MHz magnicon amplifier was carried out, including design of a 200 MW diode electron gun, design of the magnet system, optimization of beam dynamics including space charge effects in the transient and steady-state regimes, design of the drive, gain, and output cavities including an rf choke in the beam exit aperture, analysis of parasitic oscillations and design means to eliminate them, and design of the beam collector capable of 20 kW average power operation.

  18. Loss analysis of a 1 MW class HTS synchronous motor

    NASA Astrophysics Data System (ADS)

    Baik, S. K.; Kwon, Y. K.; Kim, H. M.; Lee, J. D.; Kim, Y. C.; Park, H. J.; Kwon, W. S.; Park, G. S.

    2009-03-01

    The HTS (High-Temperature Superconducting) synchronous motor has advantages over the conventional synchronous motor such as smaller size and higher efficiency. Higher efficiency is due to smaller loss than the conventional motor, so it is important to do loss analysis in order to develop a machine with higher efficiency. This paper deals with machine losses those are dissipated in each part of a HTS synchronous motor. These losses are analyzed theoretically and compared with loss data obtained from experimental results of a 1 MW class HTS synchronous motor. Each machine loss is measured based on IEEE 115 standard and the results are analyzed and considered based on the manufacturing of the test machine.

  19. Twenty-Five Years of Postseismic Viscous Relaxation Following the Mw 6.9 Loma Prieta Earthquake

    NASA Astrophysics Data System (ADS)

    Huang, M. H.; Burgmann, R.; Johanson, I. A.

    2014-12-01

    The 1989 Mw 6.9 Loma Prieta earthquake provides the first opportunity of probing the crustal and upper mantle rheology in the San Francisco Bay Area since the 1906 Mw 7.9 San Francisco earthquake. Here we use geodetic observations including GPS and InSAR to characterize the 1989 Mw 6.9 Loma Prieta earthquake postseismic displacement from 1989.8 to 2013. Pre-earthquake deformation rates are constrained by nearly 20 years of USGS trilateration measurements and removed from the postseismic measurements prior to the analysis. We observe 1-4 mm/yr GPS horizontal displacement toward the Loma Prieta epicenter until 2000, and ~2 mm/yr surface subsidence of the northern Santa Cruz Mountains between 1992 and 2002, which is not associated with the seasonal and longer-term hydrological deformation in the adjoining Santa Clara Valley. Previous work indicates afterslip dominated in the early (1989-1994) postseismic period, so we focus on modeling the postseismic viscoelastic relaxation between 1994 and 2010 based on geodetic observations. The best fitting result predicts an 11-km-thick viscoelastic lower crust with viscosity of about 1019 Pa s below a 19-km-thick elastic upper crust, underlain by a bi-viscous upper mantle with transient viscosity of 1016.5-17.5 and steady-state viscosity of 1017.5-18.5 Pa s. The millimeter scale postseismic deformation does not resolve the viscosity in different layers very well, but the inferred lithospheric rheology is consistent with estimates in southern California. The viscoelastic relaxation may also contribute to the enduring increase of aseismic slip and repeating earthquake activity on the San Andreas Fault near San Juan Bautista, which continued for at least a decade after the Loma Prieta event.

  20. Lamellar crystals as proton conductors to enhance the performance of proton exchange membrane for direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Zhao, Yuning; Jiang, Zhongyi; Xiao, Lulu; Xu, Tao; Wu, Hong

    2011-08-01

    Zirconium glyphosate (ZrG) is a solid proton conductor with layered crystal structure. The inorganic veneer sheets of ZrG are covalently intercalated by glyphosate molecules with carboxylic acid end groups (-COOH). The existence of abundant -COOH groups both inside and on the surface of ZrG provides additional proton-conducting channels facilitating the proton conduction through and around the inorganic crystals. ZrG is incorporated into the sulfonated polyether ether ketone (SPEEK) matrices to prepare proton-conducting hybrid membranes. The conductivity of the hybrid membranes is higher than the pristine SPEEK membrane, and increases with increasing ZrG content. Furthermore, the enhancement of the proton conductivity is more obvious at elevated temperatures. At 25 °C, the proton conductivity of the hybrid membrane with 16 wt% ZrG is 1.4 times higher than that of the pristine membrane. When the temperature increases to 55 °C, the conductivity of the hybrid membrane with 8 wt% ZrG is more than twice that of the pristine SPEEK membrane. The prolonged and tortuous pathways originated from the incorporation of inorganic crystals lead to reduced methanol permeability. The selectivity of the hybrid membrane is increased by as much as 72% compared to the pristine SPEEK membrane.

  1. R&D of A MW-class solid-target for a spallation neutron source

    NASA Astrophysics Data System (ADS)

    Kawai, Masayoshi; Furusaka, Michihiro; Kikuchi, Kenji; Kurishita, Hiroaki; Watanabe, Ryuzo; Li, Jing-Feng; Sugimoto, Katsuhisa; Yamamura, Tsutomu; Hiraoka, Yutaka; Abe, Katsunori; Hasegawa, Akira; Yoshiie, Masatoshi; Takenaka, Hiroyuki; Mishima, Katsuichiro; Kiyanagi, Yoshiaki; Tanabe, Tetsuo; Yoshida, Naoaki; Igarashi, Tadashi

    2003-05-01

    R&D for a MW-class solid target composed of tungsten was undertaken to produce a pulsed intense neutron source for a future neutron scattering-facility. In order to solve the corrosion of tungsten, tungsten target blocks were clad with tantalum by means of HIP'ing, brazing and electrolytic coating in a molten salt bath. The applicability of the HIP'ing method was tested through fabricating target blocks for KENS (spallation neutron source at KEK). A further investigation to certify the optimum HIP conditions was made with the small punch test method. The results showed that the optimum temperature was 1500 °C at which the W/Ta interface gave the strongest fracture strength. In the case of the block with a hole for thermocouple, it was found that the fabrication preciseness of a straight hole and a tantalum sheath influenced the results. The development of a tungsten stainless-steel alloy was tried to produce a bare tungsten target, using techniques in powder metallurgy. Corrosion tests for various tungsten alloys were made while varying the water temperature and velocity. The mass loss of tungsten in very slow water at 180 °C was as low as 0.022 mg/y, but increased remarkably with water velocity. Simulation experiments for radiation damage to supplement the STIP-III experiments were made to investigate material hardening by hydrogen and helium, and microstructures irradiated by electrons. Both experiments showed consistent results on the order of the dislocation numbers and irradiation hardness among the different tungsten materials. Thermal-hydraulic designs were made for two types of solid target system of tungsten: slab and rod geometry as a function of the proton beam power. The neutronic performance of a solid target system was compared with that of mercury target based on Monte Carlo calculations by using the MCNP code.

  2. Synthesis and Photophysical and Electroluminescent Properties of Poly(1,4-phenylene–ethynylene)-alt-poly(1,4-phenylene–vinylene)s with Various Dissymmetric Substitution of Alkoxy Side Chains

    PubMed Central

    2016-01-01

    The synthesis and characterization of a set of conjugated polymers, poly(1,4-phenylene–ethynylene)-alt-poly(1,4-phenylene–vinylene)s (PPE–PPVs), with a dissymmetrical configuration (partial or total) of alkoxy side chains is reported. Five new polymers bearing octyloxy and/or octadecyloxy side chains at the phenylene–ethynylene and phenylene–vinylene segments, respectively, were obtained. Two symmetrical substituted polymers were used for comparison. Polymers with weight-average molecular weight, Mw, up to 430 000 g/mol and degree of polymerization between 17 and 322 were obtained by a Horner–Wadsworth–Emmons olefination polycondensation reaction of the respective luminophoric dialdehydes and bisphosphonates. As expected, identical conjugated backbones in all polymers results in very similar photophysical response in dilute solution, with high fluorescence quantum yields between 50% and 80%. In contrast, the thin film properties are dependent on the combinatorial effects of side chain configuration, molecular weight, and film thickness parameters, which are the basis of the resulting comparison and discussion. PMID:26877550

  3. Measurement of the Proton + Proton Going to Proton + Proton + Neutral Pion Cross-Section Near Threshold

    NASA Astrophysics Data System (ADS)

    Ross, M. Alan

    1991-02-01

    The first nuclear physics experiment at the IUCF Cooler is a measurement of the p+ptop+p+ pi^0 cross section near threshold. The Cooler, together with a thin internal H_2 gas jet target, allows for a precise cross section measurement by providing well-defined interaction energies and by eliminating background from p-nucleus pion production which has a much lower threshold. A cylindrically symmetric detector system has been installed in one of the straight sections of the ring and is used to detect the coincident protons in the exit channel with good energy and angular resolution. The mass of the unobserved is then deduced. Elastically scattered protons were detected at the same time and by the same detector as pion production events. Elastic scattering was used for normalization to obtain an absolute p+p top+p+pi^0 cross section.

  4. The HERA Proton

    NASA Astrophysics Data System (ADS)

    Habib, Shiraz

    2014-04-01

    The almost 1 fb-1 of ep data collected by the H1 and ZEUS collider experiments at HERA allows for a precise determination of the proton's parton distribution functions (PDFs). Measurements used to constrain the PDFs—inclusive and jet cross sections, charm contribution to the F2 proton structure function, F_2cbar c — are presented herein. The measurement process itself includes cataloguing the sensitivity of the cross sections to the various sources of correlated systematic uncertainties. In the jet measurement, correlations of a statistical nature are also quantified and catalogued. These correlations provide a basis to combine measurements of the same physical observable across different time periods, experiments and measurement methodology. The subsequent PDF fitting procedure also takes into account such correlations. The resulting HERAPDF1.5 set based on inclusive data as well as PDF sets derived from inclusive plus charm data are presented togeteher with their predictions for pp cross sections at the LHC.

  5. Proton therapy in the clinic.

    PubMed

    DeLaney, Thomas F

    2011-01-01

    The clinical advantage for proton radiotherapy over photon approaches is the marked reduction in integral dose to the patient, due to the absence of exit dose beyond the proton Bragg peak. The integral dose with protons is approximately 60% lower than that with any external beam photon technique. Pediatric patients, because of their developing normal tissues and anticipated length of remaining life, are likely to have the maximum clinical gain with the use of protons. Proton therapy may also allow treatment of some adult tumors to much more effective doses, because of normal tissue sparing distal to the tumor. Currently, the most commonly available proton treatment technology uses 3D conformal approaches based on (a) distal range modulation, (b) passive scattering of the proton beam in its x- and y-axes, and (c) lateral beam-shaping. It is anticipated that magnetic pencil beam scanning will become the dominant mode of proton delivery in the future, which will lower neutron scatter associated with passively scattered beam lines, reduce the need for expensive beam-shaping devices, and allow intensity-modulated proton radiotherapy. Proton treatment plans are more sensitive to variations in tumor size and normal tissue changes over the course of treatment than photon plans, and it is expected that adaptive radiation therapy will be increasingly important for proton therapy as well. While impressive treatment results have been reported with protons, their cost is higher than for photon IMRT. Hence, protons should ideally be employed for anatomic sites and tumors not well treated with photons. While protons appear cost-effective for pediatric tumors, their cost-effectiveness for treatment of some adult tumors, such as prostate cancer, is uncertain. Comparative studies have been proposed or are in progress to more rigorously assess their value for a variety of sites. The utility of proton therapy will be enhanced by technological developments that reduce its cost

  6. Proton conducting cerate ceramics

    SciTech Connect

    Coffey, G.W.; Pederson, L.R.; Armstrong, T.R.; Bates, J.L.; Weber, W.J.

    1995-08-01

    Cerate perovskites of the general formula AM{sub x}Ce{sub 1-x}O{sub 3-{delta}}, where A = Sr or Ba and where M = Gd, Nd, Y, Yb or other rare earth dopant, are known to conduct a protonic current. Such materials may be useful as the electrolyte in a solid oxide fuel cell operating at intermediate temperatures, as an electrochemical hydrogen separation membrane, or as a hydrogen sensor. Conduction mechanisms in these materials were evaluated using dc cyclic voltammetry and mass spectrometry, allowing currents and activation energies for proton, electron, and oxygen ion contributions to the total current to be determined. For SrYb{sub 0.05}Ce{sub 0.95}O{sub 3-{delta}}, one of the best and most environmentally stable compositions, proton conduction followed two different mechanisms: a low temperature process, characterized by an activation energy of 0.42{+-}0.04 eV, and a high temperature process, characterized by an activation energy of 1.38{+-}0.13 eV. It is believed that the low temperature process is dominated by grain boundary conduction while bulk conduction is responsible for the high temperature process. The activation energy for oxygen ion conduction (0.97{+-}0.10 eV) agrees well with other oxygen conductors, while that for electronic conduction, 0.90{+-}0.09 eV, is affected by a temperature-dependent electron carrier concentration. Evaluated by direct measurement of mass flux through a dense ceramic with an applied dc field, oxygen ions were determined to be the majority charge carrier except at the lowest temperatures, followed by electrons and then protons.

  7. Smashing Protons to Smithereens

    ScienceCinema

    Marc-André Pleier

    2016-07-12

    Pleier discusses the extraordinary research taking place at the Large Hadron Collider (LHC) — the world’s newest, biggest, and highest energy particle accelerator located at CERN. Pleier is one of hundreds of researchers from around the world working on ATLAS, a seven-story particle detector positioned at a point where the LHC’s oppositely circulating beams of protons slam into one another head-on.

  8. Proton computed tomography

    NASA Astrophysics Data System (ADS)

    Bucciantonio, Martina; Sauli, Fabio

    2015-05-01

    Proton computed tomography (pCT) is a diagnostic method capable of in situ imaging the three-dimensional density distribution in a patient before irradiation with charged particle beams. Proposed long time ago, this technology has been developed by several groups, and may become an essential tool for advanced quality assessment in hadrontherapy. We describe the basic principles of the method, its performance and limitations as well as provide a summary of experimental systems and of results achieved.

  9. 1,4-diphenylbutadiyne as a potential tritium getter

    SciTech Connect

    Miller, H.H.; Bissell, E.E.; Tsugawa, R.T.; Souers, P.C.

    1980-10-01

    Research on the acetylene compound 1,4-diphenylbutadiyne is an effort to develop an air-operative tritium gas scavenger. T/sub 2/ adds to the acetylene bond of the organic in the presence of a metal catalyst. The catalyst also stimulates the oxidation reaction as well. The butadiyne compound has shown good reaction efficiency at 300 ppM T/sub 2/ in static dry air. At this concentration 75% of the scavenged tritium was in the organic. This work has expanded to the investigation of liquid acetylenes, metal acetylene complexes, organometallics and acetylene based alcohols. The best of these compounds has gettered 100% of 10 to 500 ppM T/sub 2/ for both static and dynamic air flow conditions.

  10. Photophysics and photochemical studies of 1,4-dihydropyridine derivatives.

    PubMed

    Pávez, Paulina; Encinas, Maria Victoria

    2007-01-01

    The absorption and fluorescence properties of nifedipine (NPDHP), felodipine (CPDHP) and a series of structurally related 1,4-dihydropyridines were studied in aqueous solution and organic solvents of different properties. The absorption and fluorescence spectra were found to depend on the chemical nature of the substituents at the position 4 of the 1,4-dihydropyridine ring (DHP) and on solvent properties. In aqueous solution, the fluorescence spectra of 4-phenyl substituted compounds are blue-shifted with respect to the alkyl substituted compounds. The more fluorescent compound is CPDHP. Nifedipine is not fluorescent. All compounds, with the exception of CPDHP, present monoexponential fluorescence decay with very short lifetime (0.2-0.4 ns). CPDHP showed a biexponential emission decay with a long-lived component of 1.7 ns; this behavior is explained in terms of different conformers because of the hindered rotation of the phenyl group by the ortho-substitution. Analysis of the solvent effect on the maximum of the absorption spectrum by using the linear solvent-energy relation solvato-chromic equation indicates the redshifts are influenced by the polarizability, hydrogen bonding ability and the hydrogen bond acceptance of the solvent. Whereas, the fluorescence characteristics (spectra, quantum yields and lifetimes) are sensitive to the polarizabilty and hydrogen bond ability of the solvents. Photo-decomposition of nifedipine is dependent on the solvent properties. Faster decomposition rates were obtained in nonprotic solvents. The 4-carboxylic derivative goes to decarboxylation. Under similar conditions, the other DHP compounds did not show appreciable photodecomposition.

  11. Pion, Kaon, Proton and Antiproton Production in Proton-Proton Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Blattnig, Steve R.

    2008-01-01

    Inclusive pion, kaon, proton, and antiproton production from proton-proton collisions is studied at a variety of proton energies. Various available parameterizations of Lorentz-invariant differential cross sections as a function of transverse momentum and rapidity are compared with experimental data. The Badhwar and Alper parameterizations are moderately satisfactory for charged pion production. The Badhwar parameterization provides the best fit for charged kaon production. For proton production, the Alper parameterization is best, and for antiproton production the Carey parameterization works best. However, no parameterization is able to fully account for all the data.

  12. Polarized protons at RHIC

    SciTech Connect

    Makdisi, Y.

    1992-01-01

    The approval for construction of the Relativistic Heavy Ion Collider (RHIC) provides a potential opportunity to collide polarized proton beams at energies up to 500 GeV in the center of mass and high luminosities approaching 2 {times} 10{sup 32}/cm{sup 2}/sec. This capability is enhanced by the fact that the AGS has already accelerated polarized protons and relies on the newly completed Accumulator/Booster for providing the required polarized proton intensity and a system of spin rotators (Siberian snakes) to retain the polarization. The RHIC Spin Collaboration was formed and submitted a Letter of Intent to construct this polarized collider capability and utilize its physics opportunities. In this presentation, I will discuss the plans to upgrade the AGS, the proposed layout of the RHIC siberian snakes, and timetables. The physics focus is the measurement of the spin dependent parton distributions with such accessible probes including high p(t) jets, direct photons, and Drell Yan. The attainable sensitivities and the progress that has been reached in defining the detector requirements will be outlined.

  13. Polarized protons at RHIC

    SciTech Connect

    Makdisi, Y.

    1992-10-01

    The approval for construction of the Relativistic Heavy Ion Collider (RHIC) provides a potential opportunity to collide polarized proton beams at energies up to 500 GeV in the center of mass and high luminosities approaching 2 {times} 10{sup 32}/cm{sup 2}/sec. This capability is enhanced by the fact that the AGS has already accelerated polarized protons and relies on the newly completed Accumulator/Booster for providing the required polarized proton intensity and a system of spin rotators (Siberian snakes) to retain the polarization. The RHIC Spin Collaboration was formed and submitted a Letter of Intent to construct this polarized collider capability and utilize its physics opportunities. In this presentation, I will discuss the plans to upgrade the AGS, the proposed layout of the RHIC siberian snakes, and timetables. The physics focus is the measurement of the spin dependent parton distributions with such accessible probes including high p(t) jets, direct photons, and Drell Yan. The attainable sensitivities and the progress that has been reached in defining the detector requirements will be outlined.

  14. Design and test of a 2.25-MW transformer rectifier assembly

    NASA Technical Reports Server (NTRS)

    Cormier, R.; Daeges, J.

    1989-01-01

    A new 2.25-MW transformer rectifier assembly was fabricated for DSS-13 at Goldstone, California. The transformer rectifier will provide constant output power of 2.25 MW at any voltage from 31 kV to 125 kV. This will give a new capability of 1 MW of RF power at X-band, provided appropriate microwave tubes are in the power amplifier. A description of the design and test results is presented.

  15. Proton-proton correlations observed in two-proton radioactivity of 94Ag.

    PubMed

    Mukha, Ivan; Roeckl, Ernst; Batist, Leonid; Blazhev, Andrey; Döring, Joachim; Grawe, Hubert; Grigorenko, Leonid; Huyse, Mark; Janas, Zenon; Kirchner, Reinhard; La Commara, Marco; Mazzocchi, Chiara; Tabor, Sam L; Van Duppen, Piet

    2006-01-19

    The stability and spontaneous decay of naturally occurring atomic nuclei have been much studied ever since Becquerel discovered natural radioactivity in 1896. In 1960, proton-rich nuclei with an odd or an even atomic number Z were predicted to decay through one- and two-proton radioactivity, respectively. The experimental observation of one-proton radioactivity was first reported in 1982, and two-proton radioactivity has now also been detected by experimentally studying the decay properties of 45Fe (refs 3, 4) and 54Zn (ref. 5). Here we report proton-proton correlations observed during the radioactive decay of a spinning long-lived state of the lightest known isotope of silver, 94Ag, which is known to undergo one-proton decay. We infer from these correlations that the long-lived state must also decay through simultaneous two-proton emission, making 94Ag the first nucleus to exhibit one- as well as two-proton radioactivity. We attribute the two-proton emission behaviour and the unexpectedly large probability for this decay mechanism to a very large deformation of the parent nucleus into a prolate (cigar-like) shape, which facilitates emission of protons either from the same or from opposite ends of the 'cigar'.

  16. THE POLARIZATION PARAMETER IN ELASTIC PROTON-PROTON SCATTERING FROM .75 TO 2.84 GEV.

    DTIC Science & Technology

    PROTON SCATTERING, POLARIZATION), (*NUCLEAR SPINS, POLARIZATION), PROTON REACTIONS, ELASTIC SCATTERING, MEASUREMENT, PARTICLE ACCELERATOR TARGETS, LIQUEFIED GASES, HELIUM, CARBON, ANTIPARTICLES , PROTON CROSS SECTIONS

  17. Alkaline Earth Metal and Lanthanide(III) Complexes of Ligands Based upon 1,4,7,10-Tetraazacyclododecane-1,7-bis(acetic acid).

    PubMed

    Huskens, Jurriaan; Torres, Diego A.; Kovacs, Zoltan; André, João P.; Geraldes, Carlos F. G. C.; Sherry, A. Dean

    1997-03-26

    The macrocyclic ligand DO2A (1,4,7,10-tetraazacyclododecane-1,7-bis(acetic acid)) was prepared and used as a building block for four new macrocyclic ligands having mixed side-chain chelating groups. These ligands and their complexes with Mg(II), Ca(II), and Ln(III) were studied extensively by potentiometry, high-resolution NMR, and water proton relaxivity measurements. The protonation constants of all compounds compared well with those of other cyclen-based macrocyclic ligands. All Ca(II) complexes were found to be more stable than the corresponding Mg(II) complexes. Trends for the stabilities of the Ln(III) complexes are discussed and compared with literature data, incorporating the effects of water coordination numbers, Ln(III) contraction, and the nature of the side chains and the steric hindrance between them. (1)H NMR titrations of DO2A revealed that the first and second protonations take place preferentially at the secondary ring nitrogens, while the third and fourth involved protonation of the acetates. (17)O NMR shifts showed that the DyDO2A(+) complex had two inner-sphere water molecules. Water proton spin-lattice relaxation rates for the GdDO2A(+) complex were also consistent with water exchange between bulk water and two inner-sphere Gd(III) coordination positions. Upon formation of the diamagnetic complexes of DO2A (Ca(II), Mg(II), La(III), and Lu(III)), all of the macrocyclic ring protons became nonequivalent due to slow conformational rearrangements, while the signals for the acetate CH(2) protons remained a singlet.

  18. Structure and function of beta -1,4-galactosyltransferase.

    PubMed

    Qasba, Pradman K; Ramakrishnan, Boopathy; Boeggeman, Elizabeth

    2008-04-01

    Beta-1,4-galactosylransferase (beta4Gal-T1) participates in the synthesis of Galbeta1-4-GlcNAc-disaccharide unit of glycoconjugates. It is a trans-Golgi glycosyltransferase (Glyco-T) with a type II membrane protein topology, a short N-terminal cytoplasmic domain, a membrane-spanning region, as well as a stem and a C-terminal catalytic domain facing the trans-Golgi-lumen. Its hydrophobic membrane-spanning region, like that of other Glyco-T, has a shorter length compared to plasma membrane proteins, an important feature for its retention in the trans-Golgi. The catalytic domain has two flexible loops, a long and a small one. The primary metal binding site is located at the N-terminal hinge region of the long flexible loop. Upon binding of metal ion and sugar-nucleotide, the flexible loops undergo a marked conformational change, from an open to a closed conformation. Conformational change simultaneously creates at the C-terminal region of the flexible loop an oligosaccharide acceptor binding site that did not exist before. The loop acts as a lid covering the bound donor substrate. After completion of the transfer of the glycosyl unit to the acceptor, the saccharide product is ejected; the loop reverts to its native conformation to release the remaining nucleotide moiety. The conformational change in beta4Gal-T1 also creates the binding site for a mammary gland-specific protein, alpha-lactalbumin (LA), which changes the acceptor specificity of the enzyme toward glucose to synthesize lactose during lactation. The specificity of the sugar donor is generally determined by a few residues in the sugar-nucleotide binding pocket of Glyco-T, conserved among the family members from different species. Mutation of these residues has allowed us to design new and novel glycosyltransferases, with broader or requisite donor and acceptor specificities, and to synthesize specific complex carbohydrates as well as specific inhibitors for these enzymes.

  19. Differential Cross Sections for Proton-Proton Elastic Scattering

    NASA Technical Reports Server (NTRS)

    Norman, Ryan B.; Dick, Frank; Norbury, John W.; Blattnig, Steve R.

    2009-01-01

    Proton-proton elastic scattering is investigated within the framework of the one pion exchange model in an attempt to model nucleon-nucleon interactions spanning the large range of energies important to cosmic ray shielding. A quantum field theoretic calculation is used to compute both differential and total cross sections. A scalar theory is then presented and compared to the one pion exchange model. The theoretical cross sections are compared to proton-proton scattering data to determine the validity of the models.

  20. Synthesis and antiproliferative evaluation of 5-oxo and 5-thio derivatives of 1,4-diaryl tetrazoles.

    PubMed

    Gundugola, Aditya S; Chandra, Kusum Lata; Perchellet, Elisabeth M; Waters, Andrew M; Perchellet, Jean-Pierre H; Rayat, Sundeep

    2010-07-01

    A series of 1,4-diaryl tetrazol-5-ones were synthesized by copper mediated N-arylation of 1-phenyl-1H-tetrazol-5(4H)-one with aryl boronic acids, o-R(1)C(6)H(4)B(OH)(2) where R(1)=H, OMe, Cl, CF(3), Br, CCH. The 1,4-diaryl tetrazol-5-ones substituted with OMe, Cl, CF(3), Br underwent thionation with Lawesson's reagent to yield the corresponding 5-thio derivatives. The 1-(2-bromophenyl)-4-phenyl-1H-tetrazole-5(4H)-thione so obtained was subjected to lithiation/protonation and Sonogashira coupling to produce 1,4-diphenyl-1H-tetrazole-5(4H)-thione and 1-(2-ethynylphenyl)-4-phenyl tetrazole-5-thione, respectively. The title compounds were found to be stable to strong Lewis acid conditions. Three of these novel compounds were found to inhibit L1210 leukemia cell proliferation and SK-BR-3 breast cancer cell growth over several days in culture in vitro. Shorter tetrazole derivative treatments also reduced the expression of the Ki-67 marker of cell proliferation in SK-BR-3 cells and the rate of DNA synthesis in L1210 cells.

  1. Atmospheric photochemical degradation of 1,4-unsaturated dicarbonyls

    SciTech Connect

    Liu, X.; Jeffries, H.E.; Sexton, K.G.

    1999-12-01

    To better understand fates of aromatics hydrocarbon species in the atmosphere, the authors have investigated the transformation chemistry of butenedial (CHOCH{double{underscore}bond}CHCHO), 4-oxo-2-pentenal (CH{sub 3}COCH{double{underscore}bond}CHCHO), and 3-hexene-2, 5-dione (CH{sub 3}COCH{double{underscore}bond}CHCOCH{sub 3}). These 1,4-unsaturated dicarbonyls are known to be products of aromatic photochemical oxidation. Both hydroxyl radical (OH) and ozone (O{sub 3}) initiated smog chamber experiments under atmospheric conditions were conducted in the University of North Carolina outdoor smog chamber. Carbonyl intermediates and products were measured using the O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine derivatization method followed by gas chromatography/ion trap mass spectrometry analysis. Carbonyl products detected and identified by comparison with standards in the OH-initiated photooxidation of butenedial include formaldehyde, acrolein, glycolaldehyde, glyoxal, and malonaldehyde (CHOCH{sub 2}CHO). For 4-oxo-2-pentenal, the carbonyl products were formaldehyde, methyl vinyl ketone, glycolaldehyde, hydroxyacetone, glyoxal, methylglyoxal, and malonaldehyde. for 3-hexene-2,5-dione the products were formaldehyde, acetaldehyde, acetone, hydroxyacetone, and methylglyoxal. Carbonyl products detected in the P{sub 3}-initiated experiments with cyclohexane as the OH scavenger were formaldehyde and glyoxal in butenedial; formaldehyde, glyoxal, methyl-glyoxal, and malonaldehyde in 4-oxo-2-pentenal; and formaldehyde and methylglyoxal in 3-hexene-2,5-dione.

  2. Orbital forcing of climate 1.4 billion years ago.

    PubMed

    Zhang, Shuichang; Wang, Xiaomei; Hammarlund, Emma U; Wang, Huajian; Costa, M Mafalda; Bjerrum, Christian J; Connelly, James N; Zhang, Baomin; Bian, Lizeng; Canfield, Donald E

    2015-03-24

    Fluctuating climate is a hallmark of Earth. As one transcends deep into Earth time, however, both the evidence for and the causes of climate change become difficult to establish. We report geochemical and sedimentological evidence for repeated, short-term climate fluctuations from the exceptionally well-preserved ∼1.4-billion-year-old Xiamaling Formation of the North China Craton. We observe two patterns of climate fluctuations: On long time scales, over what amounts to tens of millions of years, sediments of the Xiamaling Formation record changes in geochemistry consistent with long-term changes in the location of the Xiamaling relative to the position of the Intertropical Convergence Zone. On shorter time scales, and within a precisely calibrated stratigraphic framework, cyclicity in sediment geochemical dynamics is consistent with orbital control. In particular, sediment geochemical fluctuations reflect what appear to be orbitally forced changes in wind patterns and ocean circulation as they influenced rates of organic carbon flux, trace metal accumulation, and the source of detrital particles to the sediment.

  3. A mechanism for 1,4-Benzoquinone-induced genotoxicity

    PubMed Central

    Son, Mi Young; Deng, Chu-Xia; Hoeijmarkers, Jan H.; Rebel, Vivienne I.; Hasty, Paul

    2016-01-01

    Benzene is a common environmental toxin and its metabolite, 1-4-Benzoquinone (BQ) causes hematopoietic cancers like myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). BQ has not been comprehensively assessed for its impact on genome maintenance, limiting our understanding of the true health risks associated with benzene exposure and our ability to identify people with increased sensitivity to this genotoxin. Here we analyze the impact BQ exposure has on wild type and DNA repair-defective mouse embryonic stem (ES) cells and wild type human cells. We find that double strand break (DSB) repair and replication fork maintenance pathways including homologous recombination (HR) and Fanconi anemia (FA) suppress BQ toxicity. BQ-induced damage efficiently stalls replication forks, yet poorly induces ATR/DNA-PKCS responses. Furthermore, the pattern of BQ-induced γH2AX and 53BP1foci is consistent with the formation of poly(ADP-ribose) polymerase 1 (PARP1)-stabilized regressed replication forks. At a biochemical level, BQ inhibited topoisomerase 1 (topo1)-mediated DNA ligation and nicking in vitro; thus providing mechanism for the cellular phenotype. These data are consistent with a model that proposes BQ interferes with type I topoisomerase's ability to maintain replication fork restart and progression leading to chromosomal instability that has the potential to cause hematopoietic cancers like MDS and AML. PMID:27340773

  4. Nucleophilic 1,4-additions for natural product discovery.

    PubMed

    Cox, Courtney L; Tietz, Jonathan I; Sokolowski, Karol; Melby, Joel O; Doroghazi, James R; Mitchell, Douglas A

    2014-09-19

    Natural products remain an important source of drug candidates, but the difficulties inherent to traditional isolation, coupled with unacceptably high rates of compound rediscovery, limit the pace of natural product detection. Here we describe a reactivity-based screening method to rapidly identify exported bacterial metabolites that contain dehydrated amino acids (i.e., carbonyl- or imine-activated alkenes), a common motif in several classes of natural products. Our strategy entails the use of a commercially available thiol, dithiothreitol, for the covalent labeling of activated alkenes by nucleophilic 1,4-addition. Modification is easily discerned by comparing mass spectra of reacted and unreacted cell surface extracts. When combined with bioinformatic analysis of putative natural product gene clusters, targeted screening and isolation can be performed on a prioritized list of strains. Moreover, known compounds are easily dereplicated, effectively eliminating superfluous isolation and characterization. As a proof of principle, this labeling method was used to identify known natural products belonging to the thiopeptide, lanthipeptide, and linaridin classes. Further, upon screening a panel of only 23 actinomycetes, we discovered and characterized a novel thiopeptide antibiotic, cyclothiazomycin C.

  5. Metabolism of [(1)(4)C]prometryn in rats.

    PubMed

    Maynard, M S; Brumback, D; Itterly, W; Capps, T; Rose, R

    1999-09-01

    [(1)(4)C]Prometryn, 2, 4-bis(isopropylamino)-6-(methylthio)-s-triazine, was orally administered to male and female rats at approximately 0.5 and 500 mg/kg; daily urine and feces were collected. After 3 or 7 days rats were sacrificed, and blood and selected tissues were isolated. The urine and feces extracts were characterized for metabolite similarity as well as for metabolite identification. Over 30 metabolites were observed, and of these, 28 were identified mostly by mass spectrometry and/or cochromatography with available reference standards. The metabolism of prometryn was shown to occur by N-demethylation, S-oxidation, S-S dimerization, OH substitution for NH(2) and SCH(3), and conjugation with glutathione or glucuronic acid. Rat liver microsomal incubations of prometryn were conducted and compared to the in vivo metabolism. Both in vivo and in vitro phase I metabolisms of prometryn were similar, with S-oxidation and N-dealkylation predominating. The involvement of cytochrome P-450 and flavin-containing monooxidase in the in vitro metabolism of prometryn was investigated.

  6. Phytoremediation of 1,4-dioxane-containing recovered groundwater.

    PubMed

    Ferro, Ari M; Kennedy, Jean; LaRue, James C

    2013-01-01

    The results of a pilot-scale phytoremediation study are reported in this paper. Small plots of trees established on a closed municipal waste landfill site were irrigated with recovered groundwater containing 1,4-dioxane (dioxane) and other volatile organic compounds (VOCs). The plots were managed to minimize the leaching of irrigation water, and leaching was quantified by the use of bromide tracer. Results indicated that the dioxane (2.5 microg/L) was effectively removed, probably via phytovolatilization, and that a full-scale phytoremediation system could be used. A system is now in place at the site in which the recovered groundwater can be treated using two different approaches. A physical treatment system (PTS) will be used during the winter months, and a 12 ha phytoremediation system (stands of coniferous trees) will be used during the growing season. The PTS removes VOCs using an air-stripper, and destroys dioxane using a photo-catalytic oxidation process. Treated water will be routed to the local sewer system. The phytoremediation system, located on the landfill, will be irrigated with effluent from the PTS air-stripper containing dioxane. Seasonal use of the phytoremediation system will reduce reliance on the photo-catalytic oxidation process that is extremely energy consumptive and expensive to operate.

  7. Orbital forcing of climate 1.4 billion years ago

    PubMed Central

    Zhang, Shuichang; Wang, Xiaomei; Hammarlund, Emma U.; Wang, Huajian; Costa, M. Mafalda; Bjerrum, Christian J.; Connelly, James N.; Zhang, Baomin; Bian, Lizeng; Canfield, Donald E.

    2015-01-01

    Fluctuating climate is a hallmark of Earth. As one transcends deep into Earth time, however, both the evidence for and the causes of climate change become difficult to establish. We report geochemical and sedimentological evidence for repeated, short-term climate fluctuations from the exceptionally well-preserved ∼1.4-billion-year-old Xiamaling Formation of the North China Craton. We observe two patterns of climate fluctuations: On long time scales, over what amounts to tens of millions of years, sediments of the Xiamaling Formation record changes in geochemistry consistent with long-term changes in the location of the Xiamaling relative to the position of the Intertropical Convergence Zone. On shorter time scales, and within a precisely calibrated stratigraphic framework, cyclicity in sediment geochemical dynamics is consistent with orbital control. In particular, sediment geochemical fluctuations reflect what appear to be orbitally forced changes in wind patterns and ocean circulation as they influenced rates of organic carbon flux, trace metal accumulation, and the source of detrital particles to the sediment. PMID:25775605

  8. Solar wind halo electrons from 1-4 AU

    NASA Technical Reports Server (NTRS)

    Mccomas, D. J.; Bame, S. J.; Feldman, W. C.; Gosling, J. T.; Phillips, J. L.

    1992-01-01

    Observations from the Ulysses solar wind electron spectrometer are used to make a first examination of the evolution of the solar wind suprathermal or halo electron population as a function of heliocentric distance beyond 1 AU. As the core population cools with increasing heliocentric distance, no gap is formed between the core and halo populations. Rather, the halo electrons extend to increasingly lower energies. As predicted previously on theoretical grounds, the ratio of the core electron temperature to the low energy cutoff of the halo population appears to be roughly constant with a value of about 7.5. The total integrated heat flux drops rapidly with increasing heliocentric distance; a best fit power law of R exp -2.36 is found. In addition, it is found that the ratio of the halo to core densities is roughly constant over heliocentric distance with the halo representing 4 percent of the total electron distribution. These results suggest that the halo population may not consist of truly noninteractive test particles over the heliocentric range of 1-4 AU.

  9. An Updated Catalog of Taiwan Earthquakes (1900-2011) with Homogenized Mw Magnitudes

    NASA Astrophysics Data System (ADS)

    Chen, K.; Tsai, Y.; Chang, W.

    2012-12-01

    A complete and consistent catalog of earthquakes can provide good data for studying the distribution of earthquakes in a region as function of space, time and magnitude. Therefore, it is a basic tool for studying seismic hazard and mitigating hazard, and we can get the seismicity with magnitude equal to or greater than Mw from the data set. In the article for completeness and consistence, we apply a catalog of earthquakes from 1900 to 2006 with homogenized magnitude (Mw) (Chen and Tsai, 2008) as a base, and we also refer to the Hsu (1989) to incorporate available supplementary data (total 188 data) for the period 1900-1935, the supplementary data lead the cutoff threshold magnitude to be from Mw 5.5 down to 5.0, this indicates that we add the additional data has enriched the magnitude > 5.0 content. For this study, the catalog has been updated to include earthquakes up to 2011, and it is complete for Mw > 5.0, this will increase the reliability for studying seismic hazard. It is found that it is saturated for original catalog of Taiwan earthquakes compared with Harvard Mw or USGS M for magnitude > 6.5. Although, we modified the original catalog into seismic moment magnitude Mw, it still does not overcome the drawback. But, it is found for Mw < 6.5, our unified Mw are most greater than Harvard Mw or USGS M, the phenomenon indicates our unified Mw to supplement the gap above magnitude > 6.0 and somewhere magnitude > 5.5 during the time period 1973-1991 for original catalog. Therefore, it is better with Mw to report the earthquake magnitude.

  10. Hydrogen bonding: a channel for protons to transfer through acid-base pairs.

    PubMed

    Wu, Liang; Huang, Chuanhui; Woo, Jung-Je; Wu, Dan; Yun, Sung-Hyun; Seo, Seok-Jun; Xu, Tongwen; Moon, Seung-Hyeon

    2009-09-10

    Different from H(3)O(+) transport as in the vehicle mechanism, protons find another channel to transfer through the poorly hydrophilic interlayers in a hydrated multiphase membrane. This membrane was prepared from poly(phthalazinone ether sulfone kentone) (SPPESK) and H(+)-form perfluorosulfonic resin (FSP), and poorly hydrophilic electrostatically interacted acid-base pairs constitute the interlayer between two hydrophilic phases (FSP and SPPESK). By hydrogen bonds forming and breaking between acid-base pairs and water molecules, protons transport directly through these poorly hydrophilic zones. The multiphase membrane, due to this unique transfer mechanism, exhibits better electrochemical performances during fuel cell tests than those of pure FSP and Nafion-112 membranes: 0.09-0.12 S cm(-1) of proton conductivity at 25 degrees C and 990 mW cm(-2) of the maximum power density at a current density of 2600 mA cm(-2) and a cell voltage of 0.38 V.

  11. Design of a 100 MW X-band klystron

    SciTech Connect

    Eppley, K.

    1989-02-01

    Future linear colliders will require klystrons with higher peak power at higher frequency than are currently in use. SLAC is currently designing a 100 MW klystron at 11.4 GHz as a prototype for such a tube. The gun has been designed for 440 KV and 510 amps. Transporting this beam through a 5 mm radius X-band drift tube presents the major design problem. The area convergence ratio of 190 to one is over ten times higher than is found in conventional klystrons. Even with high magnetic fields of 6 to 7 kilogauss careful matching is required to prevent excessive scalloping. Extensive EGUN and CONDOR simulations have been made to optimize the transmission and rf efficiency. The EGUN simulations indicate that better matching is possible by using resonant magnetic focusing. CONDOR calculations indicate efficiencies of 45 percent are possible with a double output cavity. We will discuss the results of the simulations and the status of the experimental program. 3 refs., 6 figs., 2 tabs.

  12. NASA Ames Research Center 60 MW Power Supply Modernization

    NASA Technical Reports Server (NTRS)

    Choy, Yuen Ching; Ilinets, Boris V.; Miller, Ted; Nagel, Kirsten (Technical Monitor)

    2001-01-01

    The NASA Ames Research Center 60 MW DC Power Supply was built in 1974 to provide controlled DC power for the Thermophysics Facility Arc Jet Laboratory. The Power Supply has gradually losing reliability due to outdated technology and component life limitation. NASA has decided to upgrade the existing rectifier modules with contemporary high-power electronics and control equipment. NASA plans to complete this project in 2001. This project includes a complete replacement of obsolete thyristor stacks in all six rectifier modules and rectifier bridge control system. High power water-cooled thyristors and freewheeling diodes will be used. The rating of each of the six modules will be 4000 A at 5500 V. The control firing angle signal will be sent from the Facility Control System to six modules via fiberoptic cable. The Power Supply control and monitoring system will include a Master PLC in the Facility building and a Slave PLC in each rectifier module. This system will also monitor each thyristor level in each stack and the auxiliary equipment.

  13. Development of a 50 MW Multiple Beam Klystron

    SciTech Connect

    Ives, R Lawrence; Ferguson, Patrick; Read, Michael; Collins, George

    2007-10-31

    The goal of this program was to develop a 50 MW, multiple beam klystron at 11.424 GHz. The device uses eight electron guns and beam lines to achieve the required power level at a beam voltage of 190 kV, consistent with solid state power supplies. The electron gun operates with confined flow focusing, which is unique among current multiple beam sources, and allows operation at power levels consistent with producing 10s of MWs of pulsed RF power. The circuit consists of a ring resonator input cavity, eight sets of buncher cavities, and a ring resonator output cavity. The RF output power is coupled into four rectangular waveguides equally spaced around the klystron. Eight individual collectors absorb the spent beam power in each beam. The klystron operates in a solenoid. The principle challenges in the design included development of the beam optics using confined flow focusing, shaping of the magnetic field in the gun region to avoid beam spiraling, coupling input power equally to all eight beam lines from a single input, and obtaining the required frequency and Q in the output cavity. The mechanical design was particularly complex due to the large parts count, number of braze and weld joints, and close proximity of the beam lines that limited access. Addressing vacuum leaks and cold testing the complex structures was particularly troublesome. At the conclusion of the program, the klystron is experiencing several vacuum leaks that are under repair. Efforts will continue to seal and test the klystron.

  14. Design and testing of a 320 MW pulsed power supply

    SciTech Connect

    Schillig, J.B.; Boenig, H.J.; Ferner, J.A.

    1998-03-01

    For a 60 Tesla, 100 millisecond long pulse magnet five 64 MW (87.6 MVA) power converter modules have been installed. Each module provides a no-load voltage of 4.18 kV and a full load voltage of 3.20 kV at the rated current of 20 kA. The modules are connected to a 1,430 MVA/650 MJ inertial energy storage generator set, which is operated at 21 kV and frequencies between 60 and 42 Hz. They are designed to provide the rated power output for 2 seconds once every hour. Each module consists of two 21 kV/3.1 kV cast coil transformers and two 6-pulse rectifiers connected in parallel without an interphase reactor, forming a 12-pulse converter module. As far as possible standard high power industrial converter components were used, operated closer to their allowable limits. The converters are controlled by three programmable high speed controllers. In this paper the design of the pulsed converters, including control and special considerations for protection schemes with the converters supplying a mutually coupled magnet system, is detailed. Test results of the converters driving an ohmic-inductive load for 2 seconds at 20 kA and 3.2 kV are presented.

  15. Proton structure functions at HERA

    NASA Astrophysics Data System (ADS)

    Abt, Iris

    2014-05-01

    The "proton structure" is a wide field. Discussed are predominantly the precision measurements of the proton structure functions at HERA and some of their implications for the LHC measurements. In addition, a discussion of what a proton structure function represents is provided. Finally, a connection to nuclear physics is attempted. This contribution is an updated reprint of a contribution to "Deep Inelastic Scattering 2012".1

  16. Proton irradiation and endometriosis

    SciTech Connect

    Wood, D.H.; Yochmowitz, M.G.; Salmon, Y.L.; Eason, R.L.; Boster, R.A.

    1983-08-01

    Female rhesus monkeys given single total-body exposures of protons of varying energies developed endometriosis at a frequency significantly higher than that of nonirradiated animals of the same age. The minimum latency period was 7 years after exposure. The doses and energies of the radiation received were within the range that could be received by an aircrew member in near-earth orbit during a random solar flare event, leading to the conclusion that endometriosis should be a consideration in assessing the risk of delayed radiation effects in female crewmembers.

  17. Proton Size Anomaly

    SciTech Connect

    Barger, Vernon; Chiang, Cheng-Wei; Keung, Wai-Yee; Marfatia, Danny

    2011-04-15

    A measurement of the Lamb shift in muonic hydrogen yields a charge radius of the proton that is smaller than the CODATA value by about 5 standard deviations. We explore the possibility that new scalar, pseudoscalar, vector, and tensor flavor-conserving nonuniversal interactions may be responsible for the discrepancy. We consider exotic particles that, among leptons, couple preferentially to muons and mediate an attractive nucleon-muon interaction. We find that the many constraints from low energy data disfavor new spin-0, spin-1, and spin-2 particles as an explanation.

  18. Proton Upset Monte Carlo Simulation

    NASA Technical Reports Server (NTRS)

    O'Neill, Patrick M.; Kouba, Coy K.; Foster, Charles C.

    2009-01-01

    The Proton Upset Monte Carlo Simulation (PROPSET) program calculates the frequency of on-orbit upsets in computer chips (for given orbits such as Low Earth Orbit, Lunar Orbit, and the like) from proton bombardment based on the results of heavy ion testing alone. The software simulates the bombardment of modern microelectronic components (computer chips) with high-energy (.200 MeV) protons. The nuclear interaction of the proton with the silicon of the chip is modeled and nuclear fragments from this interaction are tracked using Monte Carlo techniques to produce statistically accurate predictions.

  19. Displacement damage effects in silicon MEMS at high proton doses

    NASA Astrophysics Data System (ADS)

    Gomes, João; Shea, Herbert R.

    2011-02-01

    We report on a study of the sensitivity of silicon MEMS to proton radiation and mitigation strategies. MEMS can degrade due to ionizing radiation (electron-hole pair creation) and non-ionizing radiation (displacement damage), such as electrons, trapped and solar protons, or cosmic rays, typically found in a space environment. Over the past few years there has been several reports on the effects of ionizing radiation in silicon MEMS, with failure generally linked to trapped charge in dielectrics. However there is near complete lack of studies on displacement damage effects in silicon- MEMS: how does silicon change mechanically due to proton irradiation? We report on an investigation on the susceptibility of 50 μm thick SOI-based MEMS resonators to displacement damages due to proton beams, with energies from 1 to 60 MeV, and annealing of this damage. We measure ppm changes on the Young's modulus and Poisson ratio by means of accurately monitoring the resonant frequency of devices in vacuum using a Laser Doppler Vibrometer. We observed for the first time an increase (up to 0.05%) of the Young's modulus of single-crystal silicon electromagnetically-actuated micromirrors after exposure to low energy protons (1-4 MeV) at high absorbed doses ~ 100 Mrad (Si). This investigation will contribute to a better understanding of the susceptibility of silicon-based MEMS to displacement damages frequently encountered in a space radiation environment, and allow appropriated design margin and shielding to be implemented.

  20. Gradients from GOCE reveal gravity changes before Pisagua Mw = 8.2 and Iquique Mw = 7.7 large megathrust earthquakes

    NASA Astrophysics Data System (ADS)

    Álvarez, Orlando; Nacif, Silvina; Spagnotto, Silvana; Folguera, Andres; Gimenez, Mario; Chlieh, Mohamed; Braitenberg, Carla

    2015-12-01

    Considerable improvements in the measurement of the Earth gravity field from GOCE satellite mission have provided global gravity field models with homogeneous coverage, high precision and good spatial resolution. In particular, the vertical gravity gradient (Tzz), in comparison to the classic Bouguer anomaly, defines more accurately superficial mass heterogeneities. Moreover, the correction of these satellite-derived data from the effect of Earth topographic masses by means of new techniques taking into account the Earth curvature, improves results in regional analyses. In a recent work we found a correlation between Tzz and slip distribution for the 2010 Maule Mw = 8.8 earthquake. In the present work, we derive the vertical gravity gradient from the last GOCE only model, corrected by the topographic effect and also by the sediments on depocenters of the offshore region at the Peru-Chile margin, in order to study a spatial relationship between different lobes of the gravity derived signal and the seismic sources of large megathrust earthquakes. In particular, we analyze this relation for the slip models of the 1996 Mw = 7.7 Nazca, 2001 Mw = 8.4 Arequipa, 2007 Mw = 8.0 Pisco events and for the slip models of the 2014 Mw = 8.2 Pisagua and Mw = 7.7 Iquique earthquakes from Schurr et al. (2014), including the previously analyzed 2010 Mw = 8.8 Maule event. Then we find a good correlation between vertical gravity gradients and main rupture zones, correlation that becomes even stronger as the event magnitude increases. Besides this, a gravity fall in the gravity gradient was noticed over the area of the main slip patches at least for the two years before 2014 Mw = 8.2 Pisagua and Mw = 7.7 Iquique earthquakes. Additionally, we found temporal variations of the gravity field after 2010 Mw = 8.8 Maule event, related to the main patches of the slip distribution, and coseismic deformation. Therefore, we analyzed vertical gravity gradient field variations as an indirect measure

  1. Grid Simulator for Testing MW-Scale Wind Turbines at NREL (Poster)

    SciTech Connect

    Gevorgian, V.; McDade, M.; Wallen, R.; Mendoza, I.; Shirazi, M.

    2011-05-01

    As described, an initiative by NREL to design and construct a 9-MVA grid simulator to operate with the existing 2.5 MW and new upcoming 5-MW dynamometer facilities will fulfill this role and bring many potential benefits to the U.S. wind industry with the ultimate goal of reducing wind energy integration costs.

  2. Proton-air and proton-proton cross sections from air shower data

    NASA Technical Reports Server (NTRS)

    Linsley, J.

    1985-01-01

    Data on the fluctuations in depth of maximum development of cosmic ray air showers, corrected for the effects of mixed primary composition and shower development fluctuations, yield values of the inelastic proton-air cross section for laboratory energies in the range 10 to the 8th power to 10 to the 10th power GeV. From these values of proton-air cross section, corresponding values of the proton-proton total cross section are derived by means of Glauber theory and geometrical scaling. The resulting values of proton-proton cross section are inconsistent with a well known 1n(2)s extrapolation of ISR data which is consistent with SPS data; they indicate a less rapid rate of increase in the interval 540 sq root of s 100000 GeV.

  3. [Proton imaging applications for proton therapy: state of the art].

    PubMed

    Amblard, R; Floquet, V; Angellier, G; Hannoun-Lévi, J M; Hérault, J

    2015-04-01

    Proton therapy allows a highly precise tumour volume irradiation with a low dose delivered to the healthy tissues. The steep dose gradients observed and the high treatment conformity require a precise knowledge of the proton range in matter and the target volume position relative to the beam. Thus, proton imaging allows an improvement of the treatment accuracy, and thereby, in treatment quality. Initially suggested in 1963, radiographic imaging with proton is still not used in clinical routine. The principal difficulty is the lack of spatial resolution, induced by the multiple Coulomb scattering of protons with nuclei. Moreover, its realization for all clinical locations requires relatively high energies that are previously not considered for clinical routine. Abandoned for some time in favor of X-ray technologies, research into new imaging methods using protons is back in the news because of the increase of proton radiation therapy centers in the world. This article exhibits a non-exhaustive state of the art in proton imaging.

  4. Proton in SRF Niobium

    SciTech Connect

    Wallace, John Paul

    2011-03-31

    Hydrogen is a difficult impurity to physically deal with in superconducting radio frequency (SRF) niobium, therefore, its properties in the metals should be well understood to allow the metal's superconducting properties to be optimized for minimum loss in the construction of resonant accelerator cavities. It is known that hydrogen is a paramagnetic impurity in niobium from NMR studies. This paramagnetism and its effect on superconducting properties are important to understand. To that end analytical induction measurements aimed at isolating the magnetic properties of hydrogen in SRF niobium are introduced along with optical reflection spectroscopy which is also sensitive to the presence of hydrogen. From the variety, magnitude and rapid kinetics found in the optical and magnetic properties of niobium contaminated with hydrogen forced a search for an atomic model. This yielded quantum mechanical description that correctly generates the activation energy for diffusion of the proton and its isotopes not only in niobium but the remaining metals for which data is available. This interpretation provides a frame work for understanding the individual and collective behavior of protons in metals.

  5. Berkeley Proton Linear Accelerator

    DOE R&D Accomplishments Database

    Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.

    1953-10-13

    A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.

  6. Proton in SRF Niobium

    NASA Astrophysics Data System (ADS)

    Wallace, John Paul

    2011-03-01

    Hydrogen is a difficult impurity to physically deal with in superconducting radio frequency (SRF) niobium, therefore, its properties in the metals should be well understood to allow the metal's superconducting properties to be optimized for minimum loss in the construction of resonant accelerator cavities. It is known that hydrogen is a paramagnetic impurity in niobium from NMR studies. This paramagnetism and its effect on superconducting properties are important to understand. To that end analytical induction measurements aimed at isolating the magnetic properties of hydrogen in SRF niobium are introduced along with optical reflection spectroscopy which is also sensitive to the presence of hydrogen. From the variety, magnitude and rapid kinetics found in the optical and magnetic properties of niobium contaminated with hydrogen forced a search for an atomic model. This yielded quantum mechanical description that correctly generates the activation energy for diffusion of the proton and its isotopes not only in niobium but the remaining metals for which data is available. This interpretation provides a frame work for understanding the individual and collective behavior of protons in metals.

  7. Emission of neutron-proton and proton-proton pairs in neutrino scattering

    NASA Astrophysics Data System (ADS)

    Ruiz Simo, I.; Amaro, J. E.; Barbaro, M. B.; De Pace, A.; Caballero, J. A.; Megias, G. D.; Donnelly, T. W.

    2016-11-01

    We use a recently developed model of relativistic meson-exchange currents to compute the neutron-proton and proton-proton yields in (νμ ,μ-) scattering from 12C in the 2p-2h channel. We compute the response functions and cross sections with the relativistic Fermi gas model for different kinematics from intermediate to high momentum transfers. We find a large contribution of neutron-proton configurations in the initial state, as compared to proton-proton pairs. In the case of charge-changing neutrino scattering the 2p-2h cross section of proton-proton emission (i.e., np in the initial state) is much larger than for neutron-proton emission (i.e., two neutrons in the initial state) by a (ω , q)-dependent factor. The different emission probabilities of distinct species of nucleon pairs are produced in our model only by meson-exchange currents, mainly by the Δ isobar current. We also analyze other effects including exchange contributions and the effect of the axial and vector currents.

  8. Proton therapy - Present and future.

    PubMed

    Mohan, Radhe; Grosshans, David

    2017-01-15

    In principle, proton therapy offers a substantial clinical advantage over conventional photon therapy. This is because of the unique depth-dose characteristics of protons, which can be exploited to achieve significant reductions in normal tissue doses proximal and distal to the target volume. These may, in turn, allow escalation of tumor doses and greater sparing of normal tissues, thus potentially improving local control and survival while at the same time reducing toxicity and improving quality of life. Protons, accelerated to therapeutic energies ranging from 70 to 250MeV, typically with a cyclotron or a synchrotron, are transported to the treatment room where they enter the treatment head mounted on a rotating gantry. The initial thin beams of protons are spread laterally and longitudinally and shaped appropriately to deliver treatments. Spreading and shaping can be achieved by electro-mechanical means to treat the patients with "passively-scattered proton therapy" (PSPT) or using magnetic scanning of thin "beamlets" of protons of a sequence of initial energies. The latter technique can be used to treat patients with optimized intensity modulated proton therapy (IMPT), the most powerful proton modality. Despite the high potential of proton therapy, the clinical evidence supporting the broad use of protons is mixed. It is generally acknowledged that proton therapy is safe, effective and recommended for many types of pediatric cancers, ocular melanomas, chordomas and chondrosarcomas. Although promising results have been and continue to be reported for many other types of cancers, they are based on small studies. Considering the high cost of establishing and operating proton therapy centers, questions have been raised about their cost effectiveness. General consensus is that there is a need to conduct randomized trials and/or collect outcomes data in multi-institutional registries to unequivocally demonstrate the advantage of protons. Treatment planning and plan

  9. Theoretical investigations of the reaction between 1,4-dithiane-2,5-diol and azomethine imines: mechanisms and diastereoselectivity.

    PubMed

    Zheng, Linjie; Qiao, Yan; Lu, Mengxue; Chang, Junbiao

    2015-07-21

    In the present study, mechanistic insights into the domino reaction between 1,4-dithiane-2,5-diol and azomethine imines were derived from the computational study with B3LYP and M06-2X functionals. On the whole, the domino process comprises two consecutive reactions: cleavage of 1,4-dithiane-2,5-diol leading to mercaptoacetaldehyde and [3 + 3] cycloaddition of mercaptoacetaldehyde with azomethine imines. The cleavage of 1,4-dithiane-2,5-diol can take place via multiple possible pathways (1A-1E), and pathway 1E in which double-methanol molecules mediate the proton transfer process is the most energetically favorable, with an energy barrier of 19.9 kcal mol(-1). For the [3 + 3] cycloaddition, three possible pathways (2F-2H) were explored. The calculated energy profiles reveal that pathway 2H with activation energies ranging from 6.9 to 10.2 kcal mol(-1) is more energetically favorable than pathways 2F and 2G. Specifically, pathway 2H comprises three reaction steps: deprotonation of mercaptoacetaldehyde by DABCO allows for the formation of the thiol anion, which subsequently launches a nucleophilic attack on azomethine imines followed by intramolecular cyclization resulting in the final products. The calculated results are in agreement with the experimental observations that the reaction can proceed most efficiently in the presence of both DABCO and methanol. Furthermore, the hydrogen bonding interaction is identified to be the main factor determining the observed diastereoselectivity The current systematic theoretical study gives a full scenario of the reaction between 1,4-dithiane-2,5-diol and azomethine imines catalyzed by DABCO, and thus provides some valuable clues for further investigation and development of this kind of important reaction.

  10. Crystal structure of intercalated four-stranded d(C3T) at 1.4 angstroms resolution

    NASA Technical Reports Server (NTRS)

    Kang, C. H.; Berger, I.; Lockshin, C.; Ratliff, R.; Moyzis, R.; Rich, A.

    1994-01-01

    The crystal structure of d(C3T), solved at 1.4 angstroms resolution, reveals that the molecule forms a four-stranded intercalated complex. It consists of two parallel-stranded duplexes, each of which is held together by cytosine-protonated cytosine base pairs. The two duplexes are intercalated with each other and have opposite strand orientation. The molecule has a flat, lath-like appearance, and the covalently bonded cytosines have a slow right-handed twist of 17.1 degrees. However, there is considerable asymmetry. On one of the flat sides, the phosphate groups are rotated away from the center of the molecule. They are held in this orientation by bridging water molecules that bind the NH of cytosine and a phosphate group of an opposite chain. There is also considerable microheterogeneity in the structure. The cytosine hemiprotonation occurs even at pH 7 where stable crystals form.

  11. Synthesis, structural and conformational properties, and gas phase reactivity of 1,4-dihydropyridine ester and ketone derivatives.

    PubMed

    Giorgi, Gianluca; Adamo, Mauro F A; Ponticelli, Fabio; Ventura, Antonio

    2010-12-07

    A new series of 4-aryl-2,6-dimethyl-1,4-dihydropyridines, characterized by ester or ketone functions at positions 3 and 5, has been synthesized. Structural and conformational properties, concerning the dihydropyridine ring and the orientation (synplanar/antiperiplanar) of the substituents have been investigated in their crystal structure and in solution by nuclear magnetic resonance. Evaluation of intermolecular and hydrogen bonding interactions as well as packing features, have been also carried out, evidencing interesting packing motifs. Their gas phase reactivity, as protonated and deprotonated molecules, has been investigated by electrospray ionization, high resolution and collision-induced dissociation multiple stage mass spectrometry. Deydrogenation reactions have been observed as a function of the capillary voltage.

  12. Evidence of 1,4-dioxane attenuation at groundwater sites contaminated with chlorinated solvents and 1,4-dioxane.

    PubMed

    Adamson, David T; Anderson, R Hunter; Mahendra, Shaily; Newell, Charles J

    2015-06-02

    There is a critical need to develop appropriate management strategies for 1,4-dioxane (dioxane) due to its widespread occurrence and perceived recalcitrance at groundwater sites where chlorinated solvents are present. A comprehensive evaluation of California state (GeoTracker) and Air Force monitoring records was used to provide significant evidence of dioxane attenuation at field sites. Temporal changes in the site-wide maximum concentrations were used to estimate source attenuation rates at the GeoTracker sites (median length of monitoring period = 6.8 years). While attenuation could not be established at all sites, statistically significant positive attenuation rates were confirmed at 22 sites. At sites where dioxane and chlorinated solvents were present, the median value of all statistically significant dioxane source attenuation rates (equivalent half-life = 31 months; n = 34) was lower than 1,1,1-trichloroethane (TCA) but similar to 1,1-dichloroethene (1,1-DCE) and trichloroethene (TCE). Dioxane attenuation rates were positively correlated with rates for 1,1-DCE and TCE but not TCA. At this set of sites, there was little evidence that chlorinated solvent remedial efforts (e.g., chemical oxidation, enhanced bioremediation) impacted dioxane attenuation. Attenuation rates based on well-specific records from the Air Force data set confirmed significant dioxane attenuation (131 out of 441 wells) at a similar frequency and extent (median equivalent half-life = 48 months) as observed at the California sites. Linear discriminant analysis established a positive correlation between dioxane attenuation and increasing concentrations of dissolved oxygen, while the same analysis found a negative correlation with metals and CVOC concentrations. The magnitude and prevalence of dioxane attenuation documented here suggest that natural attenuation may be used to manage some but not necessarily all dioxane-impacted sites.

  13. Modulatory effects of plant polyphenols on human multidrug resistance proteins 1, 4, and 5 (ABCC1, 4, and 5)

    PubMed Central

    Wu, Chung-Pu; Calcagno, Anna Maria; Hladky, Stephen B.; Ambudkar, Suresh V.; Barrand, Margery A.

    2005-01-01

    SUMMARY Plant flavonoids are polyphenolic compounds commonly found in vegetables, fruits and many food sources that form a significant portion of our diet. These compounds have been shown to interact with several ATP-Binding Cassette transporters that are linked with anticancer and antiviral drug resistance and as such, may be beneficial in modulating drug resistance. The present study investigates the interactions of six common polyphenols; quercetin, silymarin, resveratrol, naringenin, daidzein and hesperetin with the multidrug resistance associated proteins, MRP1, MRP4 and MRP5. At non-toxic concentrations, several of the polyphenols were able to modulate MRP1-, MRP4- and MRP5- mediated drug resistance though to varying extents. The polyphenols also reversed resistance to NSC251820, a compound that appears to be a good substrate for MRP4 as had been predicted by data mining studies. Furthermore, most of the polyphenols showed direct inhibition of MRP1-mediated [3H]-dinitrophenyl S-glutathione and MRP4-mediated [3H]-cGMP transport in inside-out vesicles prepared from human erythrocytes. Additionally, both quercetin and silymarin were found to inhibit MRP1-, MRP4-, and MRP5-mediated transport from intact cells with high affinity. They also had significant effects on ATPase activity of MRP1 and MRP4 without having any effect on [α-32P]8-azidoATP binding to these proteins. This suggests that these flavonoids most likely interact at the transporter’s substrate-binding sites. Collectively, these results suggest that dietary flavonoids such as quercetin and silymarin can modulate transport activities of MRP1, 4 and 5. Such interactions could influence bioavailability of anticancer and antiviral drugs in vivo and thus, should be considered for increasing efficacy in drug therapies. PMID:16156793

  14. Tomographic image of the proton

    NASA Astrophysics Data System (ADS)

    Dupré, R.; Guidal, M.; Vanderhaeghen, M.

    2017-01-01

    We have carried out a phenomenological analysis of the latest deep virtual Compton scattering experimental data based on the generalized parton distribution formalism. This allows us to extract the dependence of the spatial size of the proton on the quark's longitudinal momentum. This results in the first continuous two-dimensional momentum-space image and tomography of the proton based on experimental data.

  15. Proton Collimators for Fusion Reactors

    NASA Technical Reports Server (NTRS)

    Miley, George H.; Momota, Hiromu

    2003-01-01

    Proton collimators have been proposed for incorporation into inertial-electrostatic-confinement (IEC) fusion reactors. Such reactors have been envisioned as thrusters and sources of electric power for spacecraft and as sources of energetic protons in commercial ion-beam applications.

  16. Polarized proton collider at RHIC

    NASA Astrophysics Data System (ADS)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S. Y.; Luccio, A.; MacKay, W. W.; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A. N.

    2003-03-01

    In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998 [2]), reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to s=500 GeV.

  17. Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle

    NASA Astrophysics Data System (ADS)

    Denker, C.; Reza, J. Z.; Nelson, A. J.; Patterson, J. D.; Armstrong, T. P.; Maclennan, C. G.; Lanzerotti, L. J.

    2007-07-01

    Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and electron energy spectra (~50 keV to ~5 MeV) as measured by the HI-SCALE instrument on the Ulysses spacecraft over a time interval longer than a solar cycle (1990 to 2004). Ulysses is the only spacecraft that continually measured the inner (~1.4 to ~5 AU) heliosphere particle population during these years. The data thus provide measures of the lower-energy population of particles that a spacecraft traveling outward from Earth would have encountered and that also could have impacted the atmosphere and surface of Mars and of its satellites during this interval. Comparisons of Ulysses particle fluxes with those from the Electron, Proton, and Alpha Monitor (EPAM) instrument on the Advanced Composition Explorer (ACE) spacecraft (the HI-SCALE backup instrument) have shown that azimuthal and heliolatitude dependencies of particle fluxes in the inner heliosphere following solar events are not as extreme as might be expected. Thus the Ulysses measurements, while taken over a range of heliolatitudes, can provide important statistical information that can be used to estimate the low-energy radiation dosages and potential sputtering fluxes to planetary surfaces and to heliosphere spacecraft surfaces and solar arrays over a solar cycle.

  18. Kinetic effects of increased proton transfer distance on proton-coupled oxidations of phenol-amines.

    PubMed

    Markle, Todd F; Rhile, Ian J; Mayer, James M

    2011-11-02

    To test the effect of varying the proton donor-acceptor distance in proton-coupled electron transfer (PCET) reactions, the oxidation of a bicyclic amino-indanol (2) is compared with that of a closely related phenol with an ortho CPh(2)NH(2) substituent (1). Spectroscopic, structural, thermochemical, and computational studies show that the two amino-phenols are very similar, except that the O···N distance (d(ON)) is >0.1 Å longer in 2 than in 1. The difference in d(ON) is 0.13 ± 0.03 Å from X-ray crystallography and 0.165 Å from DFT calculations. Oxidations of these phenols by outer-sphere oxidants yield distonic radical cations (•)OAr-NH(3)(+) by concerted proton-electron transfer (CPET). Simple tunneling and classical kinetic models both predict that the longer donor-acceptor distance in 2 should lead to slower reactions, by ca. 2 orders of magnitude, as well as larger H/D kinetic isotope effects (KIEs). However, kinetic studies show that the compound with the longer proton-transfer distance, 2, exhibits smaller KIEs and has rate constants that are quite close to those of 1. For example, the oxidation of 2 by the triarylamminium radical cation N(C(6)H(4)OMe)(3)(•+) (3a(+)) occurs at (1.4 ± 0.1) × 10(4) M(-1) s(-1), only a factor of 2 slower than the closely related reaction of 1 with N(C(6)H(4)OMe)(2)(C(6)H(4)Br)(•+) (3b(+)). This difference in rate constants is well accounted for by the slightly different free energies of reaction: ΔG° (2 + 3a(+)) = +0.078 V versus ΔG° (1 + 3b(+)) = +0.04 V. The two phenol-amines do display some subtle kinetic differences: for instance, compound 2 has a shallower dependence of CPET rate constants on driving force (Brønsted α, Δ ln(k)/Δ ln(K(eq))). These results show that the simple tunneling model is not a good predictor of the effect of proton donor-acceptor distance on concerted-electron transfer reactions involving strongly hydrogen-bonded systems. Computational analysis of the observed similarity of the

  19. LIP: The Livermore Interpolation Package, Version 1.4

    SciTech Connect

    Fritsch, F N

    2011-07-06

    or invert the interpolant at an arbitrary number of points. The first section of this report describes the overall design of the package, including both forward and inverse interpolation. Sections 2-6 describe each interpolation method in detail. The software that implements this design is summarized function-by-function in Section 7. For a complete example of package usage, refer to Section 8. The report concludes with a few brief notes on possible software enhancements. For guidance on adding other functional forms to LIP, refer to Appendix B. The reader who is primarily interested in using LIP to solve a problem should skim Section 1, then skip to Sections 7.1-4. Finally, jump ahead to Section 8 and study the example. The remaining sections can be referred to in case more details are desired. Changes since version 1.1 of this document include the new Section 3.2.1 that discusses derivative estimation and new Section 6 that discusses the birational interpolation method. Section numbers following the latter have been modified accordingly.

  20. Predicting Solar Protons: A Statistical Approach

    DTIC Science & Technology

    2009-03-01

    above the background flux of protons (Kahler and Vourlidas , 2005). These are known as solar energetic protons (SEP). Some of these groups of protons...tempsep,10, ’b+’); 79 Bibliography Aschwanden, M. Physics of the solar corona , Praxis Publishing Ltd. 2004 Balch, C. C. ―SEC proton...prediction of all models measured. 15. SUBJECT TERMS Solar Energetic Protons, Solar Flares, Protons, Solar Corona , Cosmic Radiation 16

  1. 75 FR 34045 - Sodium 1,4-Dialkyl Sulfosuccinates; Exemption from the Requirement of a Tolerance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ... AGENCY 40 CFR Part 180 Sodium 1,4-Dialkyl Sulfosuccinates; Exemption from the Requirement of a Tolerance... an exemption from the requirement of a tolerance for residues of sodium 1,4-dialkyl sulfosuccinates including sodium 1,4-dihexyl sulfosuccinate (CAS Reg. No. 3006-15-3); sodium 1,4-diisobutyl...

  2. Proton decay, 1982

    NASA Astrophysics Data System (ADS)

    Marciano, W. J.

    1982-03-01

    Employing the current world average Lambda/sub MS/ = 0.160 GeV as input, the minimal Georgi-Glashow SU(5) model predicts sq sin theta/sub W/(m/sub W/) = 0.214, m/sub b/m/sub tau/ approximately 2.8 and tau/sub p approximately (0.4 approximately 12) x 10 approximately to the 29th power yr. The first two predictions are in excellent agreement with experiment; but the implied proton life time is already somewhat below the present experimental bound. In this status report, uncertainties in tau/sub p/ are described and effects of appendages to the SU(5) model (such as new fermion generations, scalars, supersymmetry, etc.) are examined.

  3. The proton (nuclear) microprobe

    NASA Astrophysics Data System (ADS)

    Legge, G. J. F.

    1989-04-01

    The scanning proton microprobe (SPMP) is closely related to the scanning electron microprobe (SEMP) or scanning electron microscope (SEM) with X-ray detector. Though the much greater elemental sensitivity of the SPMP is inherent in the physics, the generally inferior spatial resolution of the SPMP is not inherent and big improvements are possible, As its alternative name would imply, the SPMP is often used with heavier particle beams and with nuclear rather than atomic reactions. Its versatility and quantitative accuracy have justified greater instrumentation and computer power than that associated with other microprobes. It is fast becoming an industrially and commercially important instrument and there are few fields of scientific research in which it has not played a part. Notable contributions have been made in biology, medicine, agriculture, semiconductors, geology, mineralogy, extractive metallurgy, new materials, archaeology, forensic science, catalysis, industrial problems and reactor technology.

  4. Elucidating the pre- and post-nuclear intracellular processing of 1,4-dihydropyridine based gene delivery carriers.

    PubMed

    Hyvönen, Zanna; Hämäläinen, Vesa; Ruponen, Marika; Lucas, Bart; Rejman, Joanna; Vercauteren, Dries; Demeester, Jo; De Smedt, Stefaan; Braeckmans, Kevin

    2012-08-20

    The low transfection efficacy of non-viral gene delivery systems limits the therapeutic application of these vectors. Besides the inefficient release of the complexes or pDNA from endolysosomes into the cytoplasm or poor nuclear uptake, the nuclear and post-nuclear processing might unfavorably affect the transgene expression. Positively charged amphiphilic 1,4-dihydropyridine (1,4-DHP) derivatives were earlier proposed as a promising tool for the delivery of DNA into target cells in vitro and in vivo. However, the structure/activity relationship of these carriers is poorly understood as yet. In this work we studied the intracellular processing of complexes, composed of three structurally related 1,4-DHP derivatives, in a retinal pigment epithelial (ARPE-19) cell line. The pre- and post-nuclear processing of the complexes was quantified on the nuclear, mRNA and transgene expression level. Here we show that the interaction of 1,4-DHP complexes with the cell membrane temporarily increases the permeability of the ARPE-19 cell membrane for small molecular compounds. However, the main mechanism for internalization of 1,4-DHP complexes is endocytosis. We found that all examined derivatives are able to destabilize endosomal membranes by lipid exchange upon acidification. In addition, the buffering capacity of some of the compounds may contribute to the endosomal escape of the complexes as well through the proton sponge effect. Previously we reported that cellular uptake of 1,4-DHP complexes does not correlate with transgene expression. In this study we surprisingly revealed that there is no correlation between the amount of plasmids taken up by the cell and the amount of plasmids found in the cell nucleus. Furthermore, it was found that a high amount of plasmid in the nucleus does not ensure high mRNA expression, likely due to remaining interactions of the carrier with the plasmids. Neither did the expression of mRNA always result in the production of a functional protein

  5. Reaction of the immune system to low-level RF/MW exposures.

    PubMed

    Szmigielski, Stanislaw

    2013-06-01

    Radiofrequency (RF) and microwave (MW) radiation have been used in the modern world for many years. The rapidly increasing use of cellular phones in recent years has seen increased interest in relation to the possible health effects of exposure to RF/MW radiation. In 2011 a group of international experts organized by the IARC (International Agency for Research on Cancer in Lyon) concluded that RF/MW radiations should be listed as a possible carcinogen (group 2B) for humans. The incomplete knowledge of RF/MW-related cancer risks has initiated searches for biological indicators sensitive enough to measure the "weak biological influence" of RF/MWs. One of the main candidates is the immune system, which is able to react in a measurable way to discrete environmental stimuli. In this review, the impacts of weak RF/MW fields, including cell phone radiation, on various immune functions, both in vitro and in vivo, are discussed. The bulk of available evidence clearly indicates that various shifts in the number and/or activity of immunocompetent cells are possible, however the results are inconsistent. For example, a number of lymphocyte functions have been found to be enhanced and weakened within single experiments based on exposure to similar intensities of MW radiation. Certain premises exist which indicate that, in general, short-term exposure to weak MW radiation may temporarily stimulate certain humoral or cellular immune functions, while prolonged irradiation inhibits the same functions.

  6. Seismotectonics and seismogenesis of Mw7.8 Gorkha earthquake and its aftershocks

    NASA Astrophysics Data System (ADS)

    Arora, B. R.; Bansal, B. K.; Prajapati, Sanjay K.; Sutar, Anup K.; Nayak, Shailesh

    2017-01-01

    The April 25, 2015, Mw7.8 Gorkha earthquake in central Nepal was followed by intense aftershock activity, including Mw6.7 shock on April 26, 2015 and Mw7.3 shock on May 12, 2015. Synthesis of the focal mechanisms, space-time distribution of seismic activity in relation to previously imaged crustal velocity and resistivity structures reveals focusing of the Mw7.8 Gorkha earthquake near the upper surface of the thin fluid-filled low velocity and high conducting layer immediately above the plane of the detachment. On the geophysical sections, the detachment is identified as a sharp positive velocity interface. Modulation of frictional coupling and mechanical weakening by high-pore pressure fluids counteract the arc-normal stresses creating conditions for failure and nucleation of the Gorkha earthquakes on a plane sub-parallel with the detachment. Spatio-temporal patterns in aftershock activity indicate rapid alteration of main shock-induced stress fields, triggering a strong aftershock of Mw6.7. Large stress drop and increased energy released by the Mw6.7 event facilitates upward injection of high pore-pressure fluid fluxes into the hidden out-of-sequence thrust. It is suggested that decrease in shear strength along the hidden thrust plane due to the diffusion of high pore pressure fluids created conditions favourable to trigger Mw7.3 aftershock.

  7. Development of gyrotrons for fusion with power exceeding 1 MW over a wide frequency range

    NASA Astrophysics Data System (ADS)

    Kariya, T.; Imai, T.; Minami, R.; Numakura, T.; Eguchi, T.; Kato, T.; Endo, Y.; Ichimura, M.; Shimozuma, T.; Kubo, S.; Takahashi, H.; Yoshimura, Y.; Igami, H.; Ito, S.; Mutoh, T.; Sakamoto, K.; Idei, H.; Zushi, H.; Nagasaki, K.; Sano, F.; Ono, M.; Mitsunaka, Y.

    2015-09-01

    Megawatt-class gyrotrons covering a wide frequency range (14 GHz-300 GHz) are in increasing demand for nuclear fusion. Recent electron cyclotron heating and electron cyclotron current drive experiments highlight a requirement of megawatt-scale gyrotrons at a relatively lower frequency (14-35 GHz) range of some plasma devices, like GAMMA 10/PDX of the University of Tsukuba, QUEST of Kyushu University, NSTX-U of Princeton Plasma Physics Laboratory, and Heliotron J of Kyoto University. Collaborative studies for designing a new 28 GHz/35 GHz dual-frequency gyrotron and a 14 GHz gyrotron have commenced. Operation above 1 MW of 28 GHz/35 GHz dual oscillation was demonstrated experimentally. Further in the design of dual-frequency gyrotron, operations with 2 MW 3 s and 0.4 MW CW (continuous wave) at 28 GHz, and power exceeding 1 MW for 3 s at 34.8 GHz have been shown to be feasible. The 14 GHz gyrotron is expected to operate above 1 MW. We are also developing higher frequency gyrotrons (77-300 GHz). The joint program of National Institute for Fusion Science and the University of Tsukuba developed two new 154 GHz gyrotrons for the large helical device after the demonstration of three 77 GHz gyrotrons. The 154 GHz gyrotrons achieved a maximum output power of 1.25 MW and quasi-CW operation of 0.35 MW for 30 min.

  8. The 2008 Mw 6.0 Wells, Nevada Earthquake Sequence

    NASA Astrophysics Data System (ADS)

    Smith, K.; Depolo, D.; Torrisi, J.; Edwards, N.; Biasi, G.; Slater, D.

    2008-12-01

    The Mw 6.0 February 21, 2008 (06:16 AM PDT) Wells, Nevada normal faulting earthquake occurred in Town Creek Flat about 8 km northeast of the small community of Wells. A preliminary set of about 1000 aftershock relocations clearly defines a 55-60 degree southeast dipping fault plane. The structure projects to the surface along the southern end of the Snake Range, although no surface offsets have been identified. The earthquake occurred east of the Ruby Mountains and Snake Range west dipping range front faults, possibly on a northern extension of an east dipping normal fault system on the eastern side of the East Humbolt Range. The depth of the mainshock is estimated to be 10.5 km with the aftershock sequence extending to about 15 km. Typical of moderate sized Basin and Range earthquakes, the early aftershock period included several earthquakes of M > 4 and these were felt strongly by the residents of Wells. From the preliminary relocations, the source radius of the mainshock is estimated to be about 4 km, resulting in an estimated displacement of 55 to 83 cm and static stress drop of 72 to 86 bars, depending on the seismic moment estimate used. Aftershock relocations suggest a radial rupture mechanism. Fortunately, the EarthScope USArray network was operating in Nevada at the time of the event and provided unique controls on the mainshock and early aftershock locations. The earthquake occurred in an area of relatively low seismic hazard and the only permanent seismograph in the region was the U.S. National Network broadband station east of the Ruby Mountains south of Wells. The University of Utah and University of Nevada deployed locally recorded strong motion instruments in the Wells area. Also, an 8 station IP telemetered strong motion network, jointly deployed by the U.S. Geological Survey and University of Nevada Reno, provided real-time data for quick high-quality aftershock relocations and ground motion estimates. In addition, the University of Utah

  9. SW-MW infrared spectrometer for lunar mission

    NASA Astrophysics Data System (ADS)

    Banerjee, Arup; Biswas, Amiya; Joshi, Shaunak; Kumar, Ankush; Rehman, Sami; Sharma, Satish; Somani, Sandip; Bhati, Sunil; Karelia, Jitendra; Saxena, Anish; Chowdhury, Arup R.

    2016-04-01

    SW-MW Imaging Infrared Spectrometer, the Hyperspectral optical imaging instrument is envisaged to map geomorphology and mineralogy of lunar surface. The instrument is designed to image the electro-magnetic energy emanating from moon's surface with high spectral and spatial resolution for the mission duration from an altitude of 100 km. It is designed to cover 0.8 to 5 μm in 250 spectral bands with GSD 80m and swath 20km. Primarily, there are three basic optical segments in the spectrometer. They are fore optics, dispersing element and focusing elements. The payload is designed around a custom developed multi-blaze convex grating optimized for system throughput. The considerations for optimization are lunar radiation, instrument background, optical throughput, and detector sensitivity. HgCdTe (cooled using a rotary stirling cooler) based detector array (500x256 elements, 30μm) is being custom developed for the spectrometer. Stray light background flux is minimized using a multi-band filter cooled to cryogenic temperature. Mechanical system realization is being performed considering requirements such as structural, opto-mechanical, thermal, and alignment. The entire EOM is planned to be maintained at 240K to reduce and control instrument background. Al based mirror, grating, and EOM housing is being developed to maintain structural requirements along with opto- mechanical and thermal. Multi-tier radiative isolation and multi-stage radiative cooling approach is selected for maintaining the EOM temperature. EOM along with precision electronics packages are planned to be placed on the outer and inner side of Anti-sun side (ASS) deck. Power and Cooler drive electronics packages are planned to be placed on bottom side of ASS panel. Cooler drive electronics is being custom developed to maintain the detector temperature within 100mK during the imaging phase. Low noise detector electronics development is critical for maintaining the NETD requirements at different target

  10. Landscape response to the Mw7.9 Gorkha earthquake

    NASA Astrophysics Data System (ADS)

    Andermann, Christoff; Turowski, Jens; Behling, Robert; Cook, Kristen; Hovius, Niels; Marc, Odin; Roessner, Sigrid; Sens-Schoenfelder, Christoph; Emberson, Robert; Burtin, Arnaud; Dietze, Michael; Adhikari, Basanta; Parajuli, Binod

    2016-04-01

    Strong earthquakes cause transient perturbations of the near Earth's surface system. These include the widespread landsliding and subsequent mass movement and the loading of rivers with sediments. In addition, rock mass is shattered during the event, forming cracks that affect rock strength and hydrological conductivity. Often overlooked in the immediate aftermath of an earthquake, these perturbations can represent a major part of the overall disaster with an impact that can last for years before restoring to background conditions. Thus, the relaxation phase is part of the seismically induced change by an earthquake and need to be monitored in order to understand the full impact of earthquakes on the Earth system. Here, we present first results from the rapid respond earth surface processes monitoring program put in place by several European groups after the Mw7.9 Gorkha earthquake. To monitor the transient effects of the earthquake on the Earth surface system, we have installed a comprehensive network of 13 river sampling locations for daily water and sediment sampling, covering all major rivers draining the earthquake-affected areas immediately after the event. Nested within this regional network, we have installed an array of 16 seismometers and geophones and 6 weather stations in the upper Bhotekoshi catchment, covering an area of ~50 km2. The field measurements are accompanied by repeated mapping of landslide activities and volumes over subsequent seasons using high resolution optical (RapidEye) and radar imagery (TanDEM TerraSAR-X). The combination of all of these data will help when interpreting our field observation in the regional context of catastrophic failure of hillslopes and their link with sediment transport in the rivers. First river gauging observation show a pronounced increase in river discharge in the order of >20% for the respective pre-monsoon season. We interpreted this as a direct impact of the shaking on the valley-ridge scale sub

  11. Analysis of the rotational structure in the high-resolution infrared spectra of cis,cis- and trans,trans-1,4-difluorobutadiene-1-d1 and trans,trans-1,4-difluorobutadiene-1,4-d2

    SciTech Connect

    Craig, Norman C.; Chen, Yihui; Lu, Yuhua; Neese, Christopher F.; Nemchick, Deacon J.; Blake, Thomas A.

    2013-06-01

    Samples of cis,cis- and trans,trans-1,4-difluorobutadiene-1- d1 and of trans,trans-1,4-difluorobutadiene-1,4-d2 have been synthesized, and high-resolution (≤0.0018 cm-1) infrared spectra of these substances have been recorded in the gas phase. Analysis of the rotational structure, mostly in C-type bands, has yielded ground state rotational constants. For the two 1-d1 species more than one band has been analyzed. For the 1,4-d2 species only one band was available for analysis. However, good agreement between the experimental centrifugal distortion constants and those predicted with a B3LYP/cc-pVTZ model give strong support to the analysis of the very dense spectrum. The ground state rotational constants are a contribution to finding semiexperimental equilibrium structures of the two nonpolar isomers of 1,4- difluorobutadiene.

  12. Sulphonated imidized graphene oxide (SIGO) based polymer electrolyte membrane for improved water retention, stability and proton conductivity

    NASA Astrophysics Data System (ADS)

    Pandey, Ravi P.; Shahi, Vinod K.

    2015-12-01

    Sulphonated imidized graphene oxide (SIGO) (graphene oxide (GO) tethered sulphonated polyimide) has been successfully synthesized by polycondensation reaction using dianhydride and sulphonated diamine. Polymer electrolyte membranes (PEMs) are prepared by using SIGO (different wt%) and sulphonated poly(imide) (SPI). Resultant SPI/SIGO composite PEMs exhibit improved stabilities (thermal, mechanical and oxidative) and good water-retention properties (high bound water content responsible for proton conduction at high temperature by internal self-humidification). Incorporation of covalent bonded SIGO into SPI matrix results hydrophobic-hydrophilic phase separation and facile architecture of proton conducting path. Well optimized sulphonated poly(imide)/sulphonated imidized graphene oxide (15 wt%) (SPI/SIGO-15) composite membrane shows 2.24 meq g-1 ion-exchange capacity (IEC); 11.38 × 10-2 S cm-1 proton conductivity; 5.12% bound water content; and 10.52 × 10-7 cm2 s-1 methanol permeability. Maximum power density for pristine SPI membrane (57.12 mW cm-2) improves to 78.53 mW cm-2 for SPI/SIGO-15 membrane, in single-cell direct methanol fuel cell (DMFC) test at 70 °C using 2 M methanol fuel. Under similar experimental conditions, Nafion 117 membrane exhibits 62.40 mW cm-2 maximum power density. Reported strategy for the preparation of PEMs, offers a useful protocol for grafting of functionalized inorganic materials with in organic polymer chain by imidization.

  13. Design of interaction cavity for 170 GHz, 1 MW ITER gyrotron

    SciTech Connect

    Kumar, Anil; Kumar, Nitin; Khatun, Hasina; Singh, Udaybir; Sinha, A.K. E-mail: aksinha@ceeri.ernet.in; Vyas, V.

    2011-07-01

    In this paper the design of interaction cavity for 170 GHz, 1 MW gyrotron is presented. An in-house developed code GCOMS has been used for operating mode selection and mode competition. For 170 GHz, 1 MW gyrotron interaction cavity TE28, 7 mode excite as a operating mode at the fundamental harmonic number. The electromagnetic simulator-MAGIC, a Particle-in-Cell (PIC) code has been used for the cold cavity analysis and the beam-wave interaction. More than 1MW output power has been achieved at guiding cavity magnetic field 6.77 T. (author)

  14. Development and Production of a 201 MHz, 5.0 MW Peak Power Klystron

    SciTech Connect

    Aymar, Galen; Eisen, Edward; Stockwell, Brad; Begum, rasheda; Lenci, Steve; Eisner, Rick; Cesca, Eugene

    2016-01-01

    Communications & Power Industries LLC has designed and manufactured the VKP-8201A, a high peak power, high gain, VHF band klystron. The klystron operates at 201.25 MHz, with 5.0 MW peak output power, 34 kW average output power, and a gain of 36 dB. The klystron is designed to operate between 1.0 MW and 4.5 MW in the linear range of the transfer curve. The klystron utilizes a unique magnetic field which enables the use of a proven electron gun design with a larger electron beam requirement. Experimental and predicted performance data are compared.

  15. Proton therapy for prostate cancer.

    PubMed

    Hoppe, Bradford; Henderson, Randal; Mendenhall, William M; Nichols, Romaine C; Li, Zuofeng; Mendenhall, Nancy P

    2011-06-01

    Proton therapy has been used in the treatment of cancer for over 50 years. Due to its unique dose distribution with its spread-out Bragg peak, proton therapy can deliver highly conformal radiation to cancers located adjacent to critical normal structures. One of the important applications of its use is in prostate cancer, since the prostate is located adjacent to the rectum and bladder. Over 30 years of data have been published on the use of proton therapy in prostate cancer; these data have demonstrated high rates of local and biochemical control as well as low rates of urinary and rectal toxicity. Although before 2000 proton therapy was available at only a couple of centers in the United States, several new proton centers have been built in the last decade. With the increased availability of proton therapy, research on its use for prostate cancer has accelerated rapidly. Current research includes explorations of dose escalation, hypofractionation, and patient-reported quality-of-life outcomes. Early results from these studies are promising and will likely help make proton therapy for the treatment of prostate cancer more cost-effective.

  16. Review of variations in Mw < 7 earthquake motions on position and TEC (Mw = 6.5 Aegean Sea earthquake sample)

    NASA Astrophysics Data System (ADS)

    Yildirim, Omer; Inyurt, Samed; Mekik, Cetin

    2016-02-01

    Turkey is a country located in the middle latitude zone, where tectonic activity is intensive. Recently, an earthquake of magnitude 6.5 Mw occurred offshore in the Aegean Sea on 24 May 2014 at 09:25 UTC, which lasted about 40 s. The earthquake was also felt in Greece, Romania, and Bulgaria in addition to Turkey. In recent years, ionospheric anomaly detection studies have been carried out because of seismicity with total electron content (TEC) computed from the global navigation satellite system's (GNSS) signal delays and several interesting findings have been published. In this study, both TEC and positional variations have been examined separately following a moderate size earthquake in the Aegean Sea. The correlation of the aforementioned ionospheric variation with the positional variation has also been investigated. For this purpose, a total of 15 stations was used, including four continuously operating reference stations in Turkey (CORS-TR) and stations in the seismic zone (AYVL, CANA, IPSA, and YENC), as well as international GNSS service (IGS) and European reference frame permanent network (EPN) stations. The ionospheric and positional variations of the AYVL, CANA, IPSA, and YENC stations were examined using Bernese v5.0 software. When the precise point positioning TEC (PPP-TEC) values were examined, it was observed that the TEC values were approximately 4 TECU (total electron content unit) above the upper-limit TEC value at four stations located in Turkey, 3 days before the earthquake at 08:00 and 10:00 UTC. At the same stations, on the day before the earthquake at 06:00, 08:00, and 10:00 UTC, the TEC values were approximately 5 TECU below the lower-limit TEC value. The global ionosphere model TEC (GIM-TEC) values published by the Centre for Orbit Determination in Europe (CODE) were also examined. Three days before the earthquake, at all stations, it was observed that the TEC values in the time period between 08:00 and 10:00 UTC were approximately 2 TECU

  17. Review of variations in Mw < 7 earthquake motions on position and tec (Mw = 6.5 aegean sea earthquake sample)

    NASA Astrophysics Data System (ADS)

    Yildirim, O.; Inyurt, S.; Mekik, C.

    2015-10-01

    Turkey is a country located in Middle Latitude zone and in which tectonic activity is intensive. Lastly, an earthquake of magnitude 6.5Mw occurred at Aegean Sea offshore on date 24 May 2014 at 12:25 UTC and it lasted approximately 40 s. The said earthquake was felt also in Greece, Romania and Bulgaria in addition to Turkey. In recent years seismic origin ionospheric anomaly detection studies have been done with TEC (Total Electron Contents) generated from GNSS (Global Navigation Satellite System) signals and the findings obtained have been revealed. In this study, TEC and positional variations have been examined seperately regarding the earthquake which occurred in the Aegean Sea. Then The correlation of the said ionospheric variation with the positional variation has been investigated. For this purpose, total fifteen stations have been used among which the data of four numbers of CORS-TR stations in the seismic zone (AYVL, CANA, IPSA, YENC) and IGS and EUREF stations are used. The ionospheric and positional variations of AYVL, CANA, IPSA and YENC stations have been examined by Bernese 5.0v software. When the (PPP-TEC) values produced as result of the analysis are examined, it has been understood that in the four stations located in Turkey, three days before the earthquake at 08:00 and 10:00 UTC, the TEC values were approximately 4 TECU above the upper limit TEC value. Still in the same stations, one day before the earthquake at 06:00, 08:00 and 10:00 UTC, it is being shown that the TEC values were approximately 5 TECU below the lower limit TEC value. On the other hand, the GIM-TEC values published by the CODE center have been examined. Still in all stations, it has been observed that three days before the earthquake the TEC values in the time portions of 08:00 and 10:00 UTC were approximately 2 TECU above, one day before the earthquake at 06:00, 08:00 and 10:00 UTC, the TEC values were approximately 4 TECU below the lower limit TEC value. Again, by using the same

  18. RHIC Polarized proton operation

    SciTech Connect

    Huang, H.; Ahrens, L.; Alekseev, I.G.; Aschenauer, E.; Atoian, G.; Bai, M.; Bazilevsky, A.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Connolly, R.; Dion, A.; D'Ottavio, T.; Drees, K.A.; Fischer, W.; Gardner, C.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Hulsart, R.L.; Laster, J.; Liu, C.; Luo, Y.; MacKay, W.W.; Makdisi, Y.; Marr, G.J.; Marusic, A.; Meot, F.; Mernick, K.; Michnoff, R,; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Poblaguev, A.; Ptitsyn, V.; Ranjibar, V.; Robert-Demolaize, G.; Roser, T.; J.; Severino, F.; Schmidke, B.; Schoefer, V.; Severino, F.; Smirnov, D.; Smith, K.; Steski, D.; Svirida, D.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J. Wang, G.; Wilinski, M.; Yip, K.; Zaltsman, A.; Zelenski, A.; Zeno, K.; Zhang, S.Y.

    2011-03-28

    The Relativistic Heavy Ion Collider (RHIC) operation as the polarized proton collider presents unique challenges since both luminosity(L) and spin polarization(P) are important. With longitudinally polarized beams at the experiments, the figure of merit is LP{sup 4}. A lot of upgrades and modifications have been made since last polarized proton operation. A 9 MHz rf system is installed to improve longitudinal match at injection and to increase luminosity. The beam dump was upgraded to increase bunch intensity. A vertical survey of RHIC was performed before the run to get better magnet alignment. The orbit control is also improved this year. Additional efforts are put in to improve source polarization and AGS polarization transfer efficiency. To preserve polarization on the ramp, a new working point is chosen such that the vertical tune is near a third order resonance. The overview of the changes and the operation results are presented in this paper. Siberian snakes are essential tools to preserve polarization when accelerating polarized beams to higher energy. At the same time, the higher order resonances still can cause polarization loss. As seen in RHIC, the betatron tune has to be carefully set and maintained on the ramp and during the store to avoid polarization loss. In addition, the orbit control is also critical to preserve polarization. The higher polarization during this run comes from several improvements over last run. First we have a much better orbit on the ramp. The orbit feedback brings down the vertical rms orbit error to 0.1mm, much better than the 0.5mm last run. With correct BPM offset and vertical realignment, this rms orbit error is indeed small. Second, the jump quads in the AGS improved input polarization for RHIC. Third, the vertical tune was pushed further away from 7/10 snake resonance. The tune feedback maintained the tune at the desired value through the ramp. To calibrate the analyzing power of RHIC polarimeters at any energy above

  19. Qweak: A Precision Measurement of the Proton's Weak Charge

    SciTech Connect

    David Armstrong; Todd Averett; James Birchall; James Bowman; Roger Carlini; Swapan Chattopadhyay; Charles Davis; J. Doornbos; James Dunne; Rolf Ent; Jens Erler; Willie Falk; John Finn; Tony Forest; David Gaskell; Klaus Grimm; C. Hagner; F. Hersman; Maurik Holtrop; Kathleen Johnston; R.T. Jones; Kyungseon Joo; Cynthia Keppel; Elie Korkmaz; Stanley Kowalski; Lawrence Lee; Allison Lung; David Mack; Stanislaw Majewski; Gregory Mitchell; Hamlet Mkrtchyan; Norman Morgan; Allena Opper; Shelley Page; Seppo Penttila; Mark Pitt; Benard Poelker; Tracy Porcelli; William Ramsay; Michael Ramsey-musolf; Julie Roche; Neven Simicevic; Gregory Smith; Riad Suleiman; Simon Taylor; Willem Van Oers; Steven Wells; W.S. Wilburn; Stephen Wood; Carl Zorn

    2004-02-05

    The Qweak experiment at Jefferson Lab aims to make a 4% measurement of the parity-violating asymmetry in elastic scattering at very low Q{sup 2} of a longitudinally polarized electron beam on a proton target. The experiment will measure the weak charge of the proton, and thus the weak mixing angle at low energy scale, providing a precision test of the Standard Model. Since the value of the weak mixing angle is approximately 1/4, the weak charge of the proton Q{sub w}{sup p} = 1-4 sin{sup 2} {theta}{sub w} is suppressed in the Standard Model, making it especially sensitive to the value of the mixing angle and also to possible new physics. The experiment is approved to run at JLab, and the construction plan calls for the hardware to be ready to install in Hall C in 2007. The theoretical context of the experiment and the status of its design are discussed.

  20. Eta Meson Production in Proton-Proton and Nuclear Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Dick, Frank

    2008-01-01

    Total cross sections for eta meson production in proton - proton collisions are calculated. The eta meson is mainly produced via decay of the excited nucleon resonance at 1535 MeV. A scalar quantum field theory is used to calculate cross sections, which also include resonance decay. Comparison between theory and experiment is problematic near threshold when resonance decay is not included. When the decay is included, the comparison between theory and experiment is much better.

  1. Molecular cloning of pigeon UDP-galactose:beta-D-galactoside alpha1,4-galactosyltransferase and UDP-galactose:beta-D-galactoside beta1,4-galactosyltransferase, two novel enzymes catalyzing the formation of Gal alpha1-4Gal beta1-4Gal beta1-4GlcNAc sequence.

    PubMed

    Suzuki, Noriko; Yamamoto, Kazuo

    2010-02-19

    We previously found that pigeon IgG possesses unique N-glycan structures that contain the Gal alpha1-4Gal beta1-4Gal beta1-4GlcNAc sequence at their nonreducing termini. This sequence is most likely produced by putative alpha1,4- and beta1,4-galactosyltransferases (GalTs), which are responsible for the biosynthesis of the Gal alpha1-4Gal and Gal beta1-4Gal sequences on the N-glycans, respectively. Because no such glycan structures have been found in mammalian glycoproteins, the biosynthetic enzymes that produce these glycans are likely to have distinct substrate specificities from the known mammalian GalTs. To study these enzymes, we cloned the pigeon liver cDNAs encoding alpha4GalT and beta4GalT by expression cloning and characterized these enzymes using the recombinant proteins. The deduced amino acid sequence of pigeon alpha4GalT has 58.2% identity to human alpha4GalT and 68.0 and 66.6% identity to putative alpha4GalTs from chicken and zebra finch, respectively. Unlike human and putative chicken alpha4GalTs, which possess globotriosylceramide synthase activity, pigeon alpha4GalT preferred to catalyze formation of the Gal alpha1-4Gal sequence on glycoproteins. In contrast, the sequence of pigeon beta4GalT revealed a type II transmembrane protein consisting of 438 amino acid residues, with no significant homology to the glycosyltransferases so far identified from mammals and chicken. However, hypothetical proteins from zebra finch (78.8% identity), frogs (58.9-60.4%), zebrafish (37.1-43.0%), and spotted green pufferfish (43.3%) were similar to pigeon beta4GalT, suggesting that the pigeon beta4GalT gene was inherited from the common ancestors of these vertebrates. The sequence analysis revealed that pigeon beta4GalT and its homologs form a new family of glycosyltransferases.

  2. Electrochemical and photophysical behavior of 1-naphthol in benzyl-n-hexadecyldimethylammonium 1,4-bis(2-ethylhexyl)sulfosuccinate large unilamellar vesicles.

    PubMed

    Cobo Solis, Airam K; Mariano Correa, N; Molina, Patricia G

    2016-06-21

    In the present contribution, 1-naphthol is investigated in large unilamellar vesicles formed from a new catanionic surfactant, benzyl-n-hexadecyldimethylammonium 1,4-bis(2-ethylhexyl)sulfosuccinate, by electrochemical and spectroscopic techniques. The electrochemical results show that 1-naphthol experiences a partition process between the water phase and the large unilamellar vesicle bilayer phase, which is corroborated by absorption spectroscopic studies at pH = 6.40 and pH = 10.75. Interestingly, studies of 1-naphthol emission in benzyl-n-hexadecyldimethylammonium 1,4-bis(2-ethylhexyl)sulfosuccinate large unilamellar vesicles at pH = 10.75 and in sodium 1,4-bis(2-ethylhexyl)sulfosuccinate water solution show that when the 1,4-bis(2-ethylhexyl)sulfosuccinate moiety is part of the bilayer, the 1,4-bis(2-ethylhexyl)sulfosuccinate polar head interacts strongly with 1-naphthol, by favoring emission from the excited neutral species resulting in the appearance of a new band close to λ = 355 nm. It seems that the large unilamellar vesicle bilayer of the catanionic vesicle slows down the proton transfer process observed in water, where only emission from 1-naphtholate is detected.

  3. Kaon photoproduction off proton

    NASA Astrophysics Data System (ADS)

    Skoupil, Dalibor; Bydžovský, Petr

    2016-11-01

    We have recently constructed our version of the Regge-plus-resonance (RPR) model and two variants of an isobar model for photoproduction of kaons on the proton, utilizing new experimental data from CLAS, LEPS, and GRAAL collaborations for adjusting free parameters of the models. Higher-spin nucleon (3/2 and 5/2) and hyperon (3/2) resonances were included using the consistent formalism by Pascalutsa and found to play an important role in data description. The set of chosen nucleon resonances in our new isobar models agrees well with the set of the most probable contributing states determined in the Bayesian analysis with the RPR model whilst only 6 out of 10 N*'s selected in the RPR fit of ours overlap with the nucleon resonant states in the Bayesian analysis. Results of two versions of the isobar model are compared to the new version of the RPR model and experimental data in the third-resonance region and their properties are discussed. We place an emphasis on the choice of resonances, the predictions in the forward- and backward-angle region as well as the choice of the hadron form factor.

  4. Design of a tunable 4-MW Free Electron Maser for heating fusion plasmas

    SciTech Connect

    Caplan, M.; Kamin, G.; Shang, C.C.; Lindquist, W.

    1993-09-01

    There is an ongoing program at the FOM institute, The Netherlands, to develop a 1-MW, long-pulse, 200-Ghz Free Electron Maser (FEM) using a DC accelerator system with depressed collector. We present an extrapolation of this design to more than 4MW of output microwave power in order to reduce the cost per kW and increase the power per module in a plasma heating system.

  5. Proton-Coupled Electron Transfer

    SciTech Connect

    Weinberg, Dave; Gagliardi, Christopher J.; Hull, Jonathan F; Murphy, Christine Fecenko; Kent, Caleb A.; Westlake, Brittany C.; Paul, Amit; Ess, Daniel H; McCafferty, Dewey Granville; Meyer, Thomas J

    2012-07-11

    Proton-Coupled Electron Transfer (PCET) describes reactions in which there is a change in both electron and proton content between reactants and products. It originates from the influence of changes in electron content on acid-base properties and provides a molecular-level basis for energy transduction between proton transfer and electron transfer. Coupled electron-proton transfer or EPT is defined as an elementary step in which electrons and protons transfer from different orbitals on the donor to different orbitals on the acceptor. There is (usually) a clear distinction between EPT and H-atom transfer (HAT) or hydride transfer, in which the transferring electrons and proton come from the same bond. Hybrid mechanisms exist in which the elementary steps are different for the reaction partners. EPT pathways such as PhO•/PhOH exchange have much in common with HAT pathways in that electronic coupling is significant, comparable to the reorganization energy with H{sub DA} ~ λ. Multiple-Site Electron-Proton Transfer (MS-EPT) is an elementary step in which an electron-proton donor transfers electrons and protons to different acceptors, or an electron-proton acceptor accepts electrons and protons from different donors. It exploits the long-range nature of electron transfer while providing for the short-range nature of proton transfer. A variety of EPT pathways exist, creating a taxonomy based on what is transferred, e.g., 1e-/2H+ MS-EPT. PCET achieves “redox potential leveling” between sequential couples and the buildup of multiple redox equivalents, which is of importance in multielectron catalysis. There are many examples of PCET and pH-dependent redox behavior in metal complexes, in organic and biological molecules, in excited states, and on surfaces. Changes in pH can be used to induce electron transfer through films and over long distances in molecules. Changes in pH, induced by local electron transfer, create pH gradients and a driving

  6. POLARIZED PROTON COLLISIONS AT RHIC.

    SciTech Connect

    BAI, M.; AHRENS, L.; ALEKSEEV, I.G.; ALESSI, J.; ET AL.

    2005-05-16

    The Relativistic Heavy Ion Collider provides not only collisions of ions but also collisions of polarized protons. In a circular accelerator, the polarization of polarized proton beam can be partially or fully lost when a spin depolarizing resonance is encountered. To preserve the beam polarization during acceleration, two full Siberian snakes were employed in RHIC. In 2002, polarized proton beams were first accelerated to 100 GeV and collided in RHIC. Beams were brought into collisions with longitudinal polarization at the experiments STAR and PHENIX by using spin rotators. Optimizing polarization transmission efficiency and improving luminosity performance are significant challenges. Currently, the luminosity lifetime in RHIC is limited by the beam-beam effect. The current state of RHIC polarized proton program, including its dedicated physics run in 2005 and efforts to optimize luminosity production in beam-beam limited conditions are reported.

  7. Spectrum of solar flare protons

    NASA Astrophysics Data System (ADS)

    Podgorny, I. M.; Balabin, Yu. V.; Podgorny, A. I.; Vashenyuk, E. V.

    2010-08-01

    Most of big solar flares are accompanied by relativistic protons. The prompt component of relativistic protons moves along the interplanetary magnetic field lines and arrives at the Earth's orbit when the flare favorably located in the western solar hemisphere. The neutron monitor measurements reveal an exponential law energy spectrum. Calculations of relativistic proton acceleration in the flare current sheet with magnetic and electric fields found from 3D MHD simulations also demonstrate an exponential law spectrum. A comparison of the measured and calculated spectra permits to estimate the rate of reconnection in the Bastille flare (14 July 2000) as ˜107cm/s. The delay component of relativistic protons exhibits a power law energy spectrum.

  8. Studying the Proton Spin Puzzle with PHENIX

    NASA Astrophysics Data System (ADS)

    Daugherity, Michael

    2012-03-01

    The proton spin puzzle remains one of the biggest mysteries in fundamental particle physics today. This talk will explore how the PHENIX Collaboration's forward W-boson program uses RHIC, the world's only polarized proton-proton collider, to probe the spin structure of the proton.

  9. Parametric Model for Astrophysical Proton-Proton Interactions and Applications

    SciTech Connect

    Karlsson, Niklas

    2007-01-01

    Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. In the high-energy regime, one of the dominant mechanisms for gamma-ray production is the decay of neutral pions produced in interactions of ultra-relativistic cosmic-ray nuclei and interstellar matter. Presented here is a parametric model for calculations of inclusive cross sections and transverse momentum distributions for secondary particles--gamma rays, e±, ve, $\\bar{v}$e, vμ and $\\bar{μ}$e--produced in proton-proton interactions. This parametric model is derived on the proton-proton interaction model proposed by Kamae et al.; it includes the diffraction dissociation process, Feynman-scaling violation and the logarithmically rising inelastic proton-proton cross section. To improve fidelity to experimental data for lower energies, two baryon resonance excitation processes were added; one representing the Δ(1232) and the other multiple resonances with masses around 1600 MeV/c2. The model predicts the power-law spectral index for all secondary particle to be about 0.05 lower in absolute value than that of the incident proton and their inclusive cross sections to be larger than those predicted by previous models based on the Feynman-scaling hypothesis. The applications of the presented model in astrophysics are plentiful. It has been implemented into the Galprop code to calculate the contribution due to pion decays in the Galactic plane. The model has also been used to estimate the cosmic-ray flux in the Large Magellanic Cloud based on HI, CO and gamma-ray observations. The transverse momentum distributions enable calculations when the proton distribution is anisotropic. It is shown that the gamma-ray spectrum and flux due to a

  10. Investigation of time-resolved proton radiography using x-ray flat-panel imaging system

    NASA Astrophysics Data System (ADS)

    Jee, K.-W.; Zhang, R.; Bentefour, E. H.; Doolan, P. J.; Cascio, E.; Sharp, G.; Flanz, J.; Lu, H.-M.

    2017-03-01

    Proton beam therapy benefits from the Bragg peak and delivers highly conformal dose distributions. However, the location of the end-of-range is subject to uncertainties related to the accuracy of the relative proton stopping power estimates and thereby the water-equivalent path length (WEPL) along the beam. To remedy the range uncertainty, an in vivo measurement of the WEPL through the patient, i.e. a proton-range radiograph, is highly desirable. Towards that goal, we have explored a novel method of proton radiography based on the time-resolved dose measured by a flat panel imager (FPI). A 226 MeV pencil beam and a custom-designed range modulator wheel (MW) were used to create a time-varying broad beam. The proton imaging technique used exploits this time dependency by looking at the dose rate at the imager as a function of time. This dose rate function (DRF) has a unique time-varying dose pattern at each depth of penetration. A relatively slow rotation of the MW (0.2 revolutions per second) and a fast image acquisition (30 frames per second, ~33 ms sampling) provided a sufficient temporal resolution for each DRF. Along with the high output of the CsI:Tl scintillator, imaging with pixel binning (2  ×  2) generated high signal-to-noise data at a very low radiation dose (~0.1 cGy). Proton radiographs of a head phantom and a Gammex CT calibration phantom were taken with various configurations. The results of the phantom measurements show that the FPI can generate low noise and high spatial resolution proton radiographs. The WEPL values of the CT tissue surrogate inserts show that the measured relative stopping powers are accurate to ~2%. The panel did not show any noticeable radiation damage after the accumulative dose of approximately 3831 cGy. In summary, we have successfully demonstrated a highly practical method of generating proton radiography using an x-ray flat panel imager.

  11. Understanding the proton's spin structure

    SciTech Connect

    Fred Myhrer; Thomas, Anthony W.

    2010-02-01

    We discuss the tremendous progress that has been towards an understanding of how the spin of the proton is distributed on its quark and gluon constituents. This is a problem that began in earnest twenty years ago with the discovery of the proton "spin crisis" by the European Muon Collaboration. The discoveries prompted by that original work have given us unprecedented insight into the amount of spin carried by polarized gluons and the orbital angular momentum of the quarks.

  12. High intensity protons in RHIC

    SciTech Connect

    Montag, C.; Ahrens, L.; Blaskiewicz, M.; Brennan, J. M.; Drees, K. A.; Fischer, W.; Huang, H.; Minty, M.; Robert-Demolaize, G.; Thieberger, P.; Yip, K.

    2012-01-05

    During the 2012 summer shutdown a pair of electron lenses will be installed in RHIC, allowing the beam-beam parameter to be increased by roughly 50 percent. To realize the corresponding luminosity increase bunch intensities have to be increased by 50 percent, to 2.5 {center_dot} 10{sup 11} protons per bunch. We list the various RHIC subsystems that are most affected by this increase, and propose beam studies to ensure their readiness. The proton luminosity in RHIC is presently limited by the beam-beam effect. To overcome this limitation, electron lenses will be installed in IR10. With the help of these devices, the headon beam-beam kick experienced during proton-proton collisions will be partially compensated, allowing for a larger beam-beam tuneshift at these collision points, and therefore increasing the luminosity. This will be accomplished by increasing the proton bunch intensity from the presently achieved 1.65 {center_dot} 10{sup 11} protons per bunch in 109 bunches per beam to 2.5 {center_dot} 10{sup 11}, thus roughly doubling the luminosity. In a further upgrade we aim for bunch intensities up to 3 {center_dot} 10{sup 11} protons per bunch. With RHIC originally being designed for a bunch intensity of 1 {center_dot} 10{sup 11} protons per bunch in 56 bunches, this six-fold increase in the total beam intensity by far exceeds the design parameters of the machine, and therefore potentially of its subsystems. In this note, we present a list of major subsystems that are of potential concern regarding this intensity upgrade, show their demonstrated performance at present intensities, and propose measures and beam experiments to study their readiness for the projected future intensities.

  13. Inelastic proton-solid collisions

    NASA Astrophysics Data System (ADS)

    Echenique, P. M.; Flores, F.

    1987-05-01

    A first-principles calculation of charge states of moving protons in Al is presented. The many-body self-energy approach combined with ordinary atomic physics has been used. We find that at high velocities, V>2V0 or 3V0 (Bohr velocity), the processes are atomiclike, while at intermediate velocities, 0.7V0proton charges.

  14. Strangeness asymmetry in the proton

    NASA Astrophysics Data System (ADS)

    Alberg, Mary

    2015-04-01

    Strangeness asymmetry in the proton may arise from fluctuations of the proton into meson-baryon pairs. The leading contributions to proton strangeness are from the KΛ , KΣ , K* Λ and K* Σ states. We use a Fock state expansion of the proton in terms of these pairs to represent the strange meson cloud. We determine the strangeness distributions of the proton in a hybrid convolution model, in which the fluctuations are represented either by light-cone wave functions or meson-baryon splitting functions. For the parton distributions of the s(s) quarks in the bare baryons(mesons) of the Fock states, we use light cone wave functions or our statistical model, which expands the bare hadrons in terms of quark-gluon states. The momentum distributions of the s and s quarks in each Fock state differ because they are constituents of different hadrons. We present our results for proton strangeness asymmetry, and compare them to NuTeV and to global parton distributions. This research has been supported in part by NSF Award 1205686.

  15. Generation of proton aurora by magnetosonic waves.

    PubMed

    Xiao, Fuliang; Zong, Qiugang; Wang, Yongfu; He, Zhaoguo; Su, Zhenpeng; Yang, Chang; Zhou, Qinghua

    2014-06-05

    Earth's proton aurora occurs over a broad MLT region and is produced by the precipitation of low-energy (2-10 keV) plasmasheet protons. Proton precipitation can alter chemical compositions of the atmosphere, linking solar activity with global climate variability. Previous studies proposed that electromagnetic ion cyclotron waves can resonate with protons, producing proton scattering precipitation. A long-outstanding question still remains whether there is another mechanism responsible for the proton aurora. Here, by performing satellite data analysis and diffusion equation calculations, we show that fast magnetosonic waves can produce trapped proton scattering that yields proton aurora. This provides a new insight into the mechanism of proton aurora. Furthermore, a ray-tracing study demonstrates that magnetosonic wave propagates over a broad MLT region, consistent with the global distribution of proton aurora.

  16. Generation of proton aurora by magnetosonic waves

    PubMed Central

    Xiao, Fuliang; Zong, Qiugang; Wang, Yongfu; He, Zhaoguo; Su, Zhenpeng; Yang, Chang; Zhou, Qinghua

    2014-01-01

    Earth's proton aurora occurs over a broad MLT region and is produced by the precipitation of low-energy (2–10 keV) plasmasheet protons. Proton precipitation can alter chemical compositions of the atmosphere, linking solar activity with global climate variability. Previous studies proposed that electromagnetic ion cyclotron waves can resonate with protons, producing proton scattering precipitation. A long-outstanding question still remains whether there is another mechanism responsible for the proton aurora. Here, by performing satellite data analysis and diffusion equation calculations, we show that fast magnetosonic waves can produce trapped proton scattering that yields proton aurora. This provides a new insight into the mechanism of proton aurora. Furthermore, a ray-tracing study demonstrates that magnetosonic wave propagates over a broad MLT region, consistent with the global distribution of proton aurora. PMID:24898626

  17. Estimation of ground motion for Bhuj (26 January 2001; Mw 7.6 and for future earthquakes in India

    USGS Publications Warehouse

    Singh, S.K.; Bansal, B.K.; Bhattacharya, S.N.; Pacheco, J.F.; Dattatrayam, R.S.; Ordaz, M.; Suresh, G.; ,; Hough, S.E.

    2003-01-01

    Only five moderate and large earthquakes (Mw ???5.7) in India-three in the Indian shield region and two in the Himalayan arc region-have given rise to multiple strong ground-motion recordings. Near-source data are available for only two of these events. The Bhuj earthquake (Mw 7.6), which occurred in the shield region, gave rise to useful recordings at distances exceeding 550 km. Because of the scarcity of the data, we use the stochastic method to estimate ground motions. We assume that (1) S waves dominate at R < 100 km and Lg waves at R ??? 100 km, (2) Q = 508f0.48 is valid for the Indian shield as well as the Himalayan arc region, (3) the effective duration is given by fc-1 + 0.05R, where fc is the corner frequency, and R is the hypocentral distance in kilometer, and (4) the acceleration spectra are sharply cut off beyond 35 Hz. We use two finite-source stochastic models. One is an approximate model that reduces to the ??2-source model at distances greater that about twice the source dimension. This model has the advantage that the ground motion is controlled by the familiar stress parameter, ????. In the other finite-source model, which is more reliable for near-source ground-motion estimation, the high-frequency radiation is controlled by the strength factor, sfact, a quantity that is physically related to the maximum slip rate on the fault. We estimate ???? needed to fit the observed Amax and Vmax data of each earthquake (which are mostly in the far field). The corresponding sfact is obtained by requiring that the predicted curves from the two models match each other in the far field up to a distance of about 500 km. The results show: (1) The ???? that explains Amax data for shield events may be a function of depth, increasing from ???50 bars at 10 km to ???400 bars at 36 km. The corresponding sfact values range from 1.0-2.0. The ???? values for the two Himalayan arc events are 75 and 150 bars (sfact = 1.0 and 1.4). (2) The ???? required to explain Vmax data

  18. Development of Proton Computed Tomography for Applications in Proton Therapy

    NASA Astrophysics Data System (ADS)

    Bashkirov, Vladimir; Schulte, Reinhard; Coutrakon, George; Erdelyi, Bela; Wong, Kent; Sadrozinski, Hartmut; Penfold, Scott; Rosenfeld, Anatoly; McAllister, Scott; Schubert, Keith

    2009-03-01

    Determination of the Bragg peak position in proton therapy requires accurate knowledge of the electron density and ratio of effective atomic number and mass (Z/A) of the body tissues traversed. While the Z/A ratio is fairly constant for human tissues, the density of tissues varies significantly. One possibility to obtain accurate electron density information of tissues is to use protons of sufficient energy to penetrate the patient and measure their energy loss. From these transmission measurements, it is possible to reconstruct a three-dimensional map of electron densities using algebraic techniques. The interest in proton computed tomography (pCT) has considerably increased in recent years due to the more common use of proton accelerators for cancer treatment world-wide and a modern design concept based on current high-energy physics technology has been suggested. This contribution gives a status update on the pCT project carried out by the pCT Collaboration, a group of institutions sharing interest and expertise in the development of pCT. We will present updated imaging data obtained with a small pCT prototype developed in collaboration with the Santa Cruz Institute of Particle Physics and installed on the proton research beam line at Loma Linda University Medical Center. We will discuss hardware decisions regarding the next-generation pCT scanner, which will permit scanning of head-sized objects. Progress has also been made in the formulation of the most likely path of protons through an object and parallelizable iterative reconstruction algorithms that can be implemented on general-purpose commodity graphics processing units. Finally, we will present simulation studies for utilizing pCT technology for on-line proton dose verification and tumor imaging with positron emission tomography (PET).

  19. 49 CFR 174.115 - Loading Division 1.4 (explosive) materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RAIL Class I (Explosive) Materials § 174.115 Loading Division 1.4 (explosive) materials. (a) Division 1... Pamphlet No. 6. (b) Division 1.4 (explosive) materials may not be transported in a truck body, trailer,...

  20. 49 CFR 173.64 - Exceptions for Division 1.3 and 1.4 fireworks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Exceptions for Division 1.3 and 1.4 fireworks. 173... § 173.64 Exceptions for Division 1.3 and 1.4 fireworks. (a) Notwithstanding the requirements of § 173.56(b), Division 1.3 and 1.4 fireworks (see § 173.65 for Division 1.4G consumer fireworks) may...

  1. 49 CFR 173.64 - Exceptions for Division 1.3 and 1.4 fireworks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Exceptions for Division 1.3 and 1.4 fireworks. 173... § 173.64 Exceptions for Division 1.3 and 1.4 fireworks. (a) Notwithstanding the requirements of § 173.56(b), Division 1.3 and 1.4 fireworks (see § 173.65 for Division 1.4G consumer fireworks) may...

  2. 43 CFR 8365.1-4 - Public health, safety and comfort.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Public health, safety and comfort. 8365.1-4 Section 8365.1-4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF... § 8365.1-4 Public health, safety and comfort. (a) No person shall cause a public disturbance or create...

  3. 43 CFR 8365.1-4 - Public health, safety and comfort.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Public health, safety and comfort. 8365.1-4 Section 8365.1-4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF... § 8365.1-4 Public health, safety and comfort. (a) No person shall cause a public disturbance or create...

  4. 43 CFR 8365.1-4 - Public health, safety and comfort.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Public health, safety and comfort. 8365.1-4 Section 8365.1-4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF... § 8365.1-4 Public health, safety and comfort. (a) No person shall cause a public disturbance or create...

  5. 43 CFR 8365.1-4 - Public health, safety and comfort.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Public health, safety and comfort. 8365.1-4 Section 8365.1-4 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF... § 8365.1-4 Public health, safety and comfort. (a) No person shall cause a public disturbance or create...

  6. 40 CFR 721.10096 - Benzene, 1,4-bis (methoxymethyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzene, 1,4-bis (methoxymethyl)-. 721... Substances § 721.10096 Benzene, 1,4-bis (methoxymethyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1,4-bis (methoxymethyl)- (PMN...

  7. 40 CFR 721.1193 - Benzene, 2-bromo-1,4-dimethoxy-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzene, 2-bromo-1,4-dimethoxy-. 721... Substances § 721.1193 Benzene, 2-bromo-1,4-dimethoxy-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 2-bromo-1,4-dimethoxy- (PMN...

  8. 40 CFR 721.1193 - Benzene, 2-bromo-1,4-dimethoxy-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzene, 2-bromo-1,4-dimethoxy-. 721... Substances § 721.1193 Benzene, 2-bromo-1,4-dimethoxy-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 2-bromo-1,4-dimethoxy- (PMN...

  9. 40 CFR 721.10096 - Benzene, 1,4-bis (methoxymethyl)-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzene, 1,4-bis (methoxymethyl)-. 721... Substances § 721.10096 Benzene, 1,4-bis (methoxymethyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1,4-bis (methoxymethyl)- (PMN...

  10. 40 CFR 721.1193 - Benzene, 2-bromo-1,4-dimethoxy-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzene, 2-bromo-1,4-dimethoxy-. 721... Substances § 721.1193 Benzene, 2-bromo-1,4-dimethoxy-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 2-bromo-1,4-dimethoxy- (PMN...

  11. 40 CFR 721.10096 - Benzene, 1,4-bis (methoxymethyl)-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzene, 1,4-bis (methoxymethyl)-. 721... Substances § 721.10096 Benzene, 1,4-bis (methoxymethyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1,4-bis (methoxymethyl)- (PMN...

  12. 40 CFR 721.1193 - Benzene, 2-bromo-1,4-dimethoxy-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzene, 2-bromo-1,4-dimethoxy-. 721... Substances § 721.1193 Benzene, 2-bromo-1,4-dimethoxy-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 2-bromo-1,4-dimethoxy- (PMN...

  13. 40 CFR 721.10096 - Benzene, 1,4-bis (methoxymethyl)-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzene, 1,4-bis (methoxymethyl)-. 721... Substances § 721.10096 Benzene, 1,4-bis (methoxymethyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1,4-bis (methoxymethyl)- (PMN...

  14. 40 CFR 721.1193 - Benzene, 2-bromo-1,4-dimethoxy-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzene, 2-bromo-1,4-dimethoxy-. 721... Substances § 721.1193 Benzene, 2-bromo-1,4-dimethoxy-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 2-bromo-1,4-dimethoxy- (PMN...

  15. 40 CFR 721.10096 - Benzene, 1,4-bis (methoxymethyl)-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzene, 1,4-bis (methoxymethyl)-. 721... Substances § 721.10096 Benzene, 1,4-bis (methoxymethyl)-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1,4-bis (methoxymethyl)- (PMN...

  16. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  17. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  18. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  19. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  20. 47 CFR 27.806 - 1.4 GHz service licenses subject to competitive bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false 1.4 GHz service licenses subject to competitive bidding. 27.806 Section 27.806 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES 1.4 GHz Band § 27.806 1.4 GHz...

  1. IRIS Toxicological Review of 1,4-Dioxane (with Inhalation Update) (Final Report)

    EPA Science Inventory

    The final IRIS Toxicological Review of 1,4-dioxane (with inhalation update) provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to 1,4-dioxane. Human health risk concerns for 1,4-dioxane are primarily relat...

  2. 10 CFR 960.3-1-4-3 - Site recommendation for characterization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Site recommendation for characterization. 960.3-1-4-3 Section 960.3-1-4-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-3 Site...

  3. 10 CFR 960.3-1-4 - Evidence for siting decisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Evidence for siting decisions. 960.3-1-4 Section 960.3-1-4 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4 Evidence for siting decisions. The...

  4. 10 CFR 960.3-1-4 - Evidence for siting decisions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Evidence for siting decisions. 960.3-1-4 Section 960.3-1-4 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4 Evidence for siting decisions. The...

  5. 10 CFR 960.3-1-4-1 - Site identification as potentially acceptable.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Site identification as potentially acceptable. 960.3-1-4-1 Section 960.3-1-4-1 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-1 Site...

  6. 10 CFR 960.3-1-4-3 - Site recommendation for characterization.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Site recommendation for characterization. 960.3-1-4-3 Section 960.3-1-4-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-3 Site...

  7. 10 CFR 960.3-1-4 - Evidence for siting decisions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Evidence for siting decisions. 960.3-1-4 Section 960.3-1-4 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4 Evidence for siting decisions. The...

  8. 10 CFR 960.3-1-4-3 - Site recommendation for characterization.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Site recommendation for characterization. 960.3-1-4-3 Section 960.3-1-4-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-3 Site...

  9. 10 CFR 960.3-1-4-1 - Site identification as potentially acceptable.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Site identification as potentially acceptable. 960.3-1-4-1 Section 960.3-1-4-1 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-1 Site...

  10. 10 CFR 960.3-1-4-3 - Site recommendation for characterization.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Site recommendation for characterization. 960.3-1-4-3 Section 960.3-1-4-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-3 Site...

  11. 10 CFR 960.3-1-4 - Evidence for siting decisions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Evidence for siting decisions. 960.3-1-4 Section 960.3-1-4 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4 Evidence for siting decisions. The...

  12. 10 CFR 960.3-1-4 - Evidence for siting decisions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Evidence for siting decisions. 960.3-1-4 Section 960.3-1-4 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4 Evidence for siting decisions. The...

  13. 10 CFR 960.3-1-4-1 - Site identification as potentially acceptable.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Site identification as potentially acceptable. 960.3-1-4-1 Section 960.3-1-4-1 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-1 Site...

  14. 10 CFR 960.3-1-4-1 - Site identification as potentially acceptable.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Site identification as potentially acceptable. 960.3-1-4-1 Section 960.3-1-4-1 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-1 Site...

  15. 10 CFR 960.3-1-4-3 - Site recommendation for characterization.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Site recommendation for characterization. 960.3-1-4-3 Section 960.3-1-4-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-1-4-3 Site...

  16. 17 CFR 240.11a1-4(T) - Bond transactions on national securities exchanges.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Bond transactions on national securities exchanges. 240.11a1-4(T) Section 240.11a1-4(T) Commodity and Securities Exchanges SECURITIES AND....11a1-4(T) Bond transactions on national securities exchanges. A transaction in a bond, note,...

  17. High Dust Depletion in two Intervening Quasar Absorption Line Systems with the 2175 Å Extinction Bump at z ~ 1.4

    NASA Astrophysics Data System (ADS)

    Jiang, Peng; Ge, Jian; Prochaska, J. Xavier; Wang, Junfeng; Zhou, Hongyan; Wang, Tinggui

    2010-12-01

    We present the column densities of heavy elements and dust depletion studies in two strong Mg II absorption systems at z ~ 1.4 displaying the 2175 Å dust extinction feature. Column densities are measured from low-ionization absorption lines using an Apparent Optical Depth Method on the Keck/ESI spectra. We find that the dust depletion patterns resemble that of cold diffuse clouds in the Milky Way (MW). The values, [Fe/Zn] ≈-1.5 and [Si/Zn]<-0.67, are among the highest dust depletion measured for quasar absorption line systems. In another 2175 Å absorber at z = 1.64 toward the quasar SDSS J160457.50+220300.5, Noterdaeme et al. reported a similar dust depletion measurement ([Fe/Zn] = -1.47 and [Si/Zn] = -1.07) and detected C I and CO absorption lines on its VLT/UVES spectrum. We conclude that heavy dust depletion (i.e., a characteristic of cold dense clouds in MW) is required to produce a pronounced 2175 Å extinction bump. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  18. Sparse-view proton computed tomography using modulated proton beams

    SciTech Connect

    Lee, Jiseoc; Kim, Changhwan; Cho, Seungryong; Min, Byungjun; Kwak, Jungwon; Park, Seyjoon; Lee, Se Byeong; Park, Sungyong

    2015-02-15

    Purpose: Proton imaging that uses a modulated proton beam and an intensity detector allows a relatively fast image acquisition compared to the imaging approach based on a trajectory tracking detector. In addition, it requires a relatively simple implementation in a conventional proton therapy equipment. The model of geometric straight ray assumed in conventional computed tomography (CT) image reconstruction is however challenged by multiple-Coulomb scattering and energy straggling in the proton imaging. Radiation dose to the patient is another important issue that has to be taken care of for practical applications. In this work, the authors have investigated iterative image reconstructions after a deconvolution of the sparsely view-sampled data to address these issues in proton CT. Methods: Proton projection images were acquired using the modulated proton beams and the EBT2 film as an intensity detector. Four electron-density cylinders representing normal soft tissues and bone were used as imaged object and scanned at 40 views that are equally separated over 360°. Digitized film images were converted to water-equivalent thickness by use of an empirically derived conversion curve. For improving the image quality, a deconvolution-based image deblurring with an empirically acquired point spread function was employed. They have implemented iterative image reconstruction algorithms such as adaptive steepest descent-projection onto convex sets (ASD-POCS), superiorization method–projection onto convex sets (SM-POCS), superiorization method–expectation maximization (SM-EM), and expectation maximization-total variation minimization (EM-TV). Performance of the four image reconstruction algorithms was analyzed and compared quantitatively via contrast-to-noise ratio (CNR) and root-mean-square-error (RMSE). Results: Objects of higher electron density have been reconstructed more accurately than those of lower density objects. The bone, for example, has been reconstructed

  19. Tsunami Characteristics Along the Peru-Chile Trench: Analysis of the 2015 Mw8.3 Illapel, the 2014 Mw8.2 Iquique and the 2010 Mw8.8 Maule Tsunamis in the Near-field

    NASA Astrophysics Data System (ADS)

    Omira, R.; Baptista, M. A.; Lisboa, F.

    2016-04-01

    Tsunamis occur quite frequently following large magnitude earthquakes along the Chilean coast. Most of these earthquakes occur along the Peru-Chile Trench, one of the most seismically active subduction zones of the world. This study aims to understand better the characteristics of the tsunamis triggered along the Peru-Chile Trench. We investigate the tsunamis induced by the Mw8.3 Illapel, the Mw8.2 Iquique and the Mw8.8 Maule Chilean earthquakes that happened on September 16th, 2015, April 1st, 2014 and February 27th, 2010, respectively. The study involves the relation between the co-seismic deformation and the tsunami generation, the near-field tsunami propagation, and the spectral analysis of the recorded tsunami signals in the near-field. We compare the tsunami characteristics to highlight the possible similarities between the three events and, therefore, attempt to distinguish the specific characteristics of the tsunamis occurring along the Peru-Chile Trench. We find that these three earthquakes present faults with important extensions beneath the continent which result in the generation of tsunamis with short wavelengths, relative to the fault widths involved, and with reduced initial potential energy. In addition, the presence of the Chilean continental margin, that includes the shelf of shallow bathymetry and the continental slope, constrains the tsunami propagation and the coastal impact. All these factors contribute to a concentrated local impact but can, on the other hand, reduce the far-field tsunami effects from earthquakes along Peru-Chile Trench.

  20. The transient outward current in mice lacking the potassium channel gene Kv1.4

    PubMed Central

    London, Barry; Wang, Dao W; Hill, Joseph A; Bennett, Paul B

    1998-01-01

    The transient outward current (Ito) plays a prominent role in the repolarization phase of the cardiac action potential. Several K+ channel genes, including Kv1.4, are expressed in the heart, produce rapidly inactivating currents when heterologously expressed, and may be the molecular basis of Ito.We engineered mice homozygous for a targeted disruption of the K+ channel gene Kv1.4 and compared Ito in wild-type (Kv1.4+/+), heterozygous (Kv1.4+/-) and homozygous ‘knockout’ (Kv1.4−/−) mice. Kv1.4 RNA was truncated in Kv1.4−/− mice and protein expression was absent.Adult myocytes isolated from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice had large rapidly inactivating outward currents. The peak current densities at 60 mV (normalized by cellular capacitance, in pA pF−1; means ± s.e.m.) were 53.8 ± 5.3, 45.3 ± 2.2 and 44.4 ± 2.8 in cells from Kv1.4+/+, Kv1.4+/− and Kv1.4−/− mice, respectively (P < 0.02 for Kv1.4+/+ vs. Kv1.4−/−). The steady-state values (800 ms after the voltage clamp step) were 30.9 ± 2.9, 26.9 ± 3.8 and 23.5 ± 2.2, respectively (P < 0.02 for Kv1.4+/+ vs. Kv1.4−/−). The inactivating portion of the current was unchanged in the targeted mice.The voltage dependence and time course of inactivation were not changed by targeted disruption of Kv1.4. The mean best-fitting V½ (membrane potential at 50 % inactivation) values for myocytes from Kv1.4 +/+, Kv1.4+/− and Kv1.4−/− mice were -53.5 ± 3.7, -51.1 ± 2.6 and -54.2 ± 2.4 mV, respectively. The slope factors (k) were -10.1 ± 1.4, -8.8 ± 1.4 and -9.5 ± 1.2 mV, respectively. The fast time constants for development of inactivation at -30 mV were 27.8 ± 2.2, 26.2 ± 5.1 and 19.6 ± 2.1 ms in Kv1.4+/+, Kv1.4+/− and Kv1.4−/− myocytes, respectively. At +30 mV, they were 35.5 ± 2.6, 30.0 ± 2.1 and 28.7 ± 1.6 ms, respectively. The time constants for the rapid phase of recovery from inactivation at -80 mV were 32.5 ± 8.2, 23.3 ± 1.8 and 39.0 ± 3.7 ms, respectively

  1. Biaryl synthesis by ring-opening Friedel-Crafts arylation of 1,4-epoxy-1,4-dihydronaphthalenes catalyzed by iron trichloride.

    PubMed

    Sawama, Yoshinari; Asai, Shota; Kawajiri, Takahiro; Monguchi, Yasunari; Sajiki, Hironao

    2015-01-26

    Biaryl and heterobiaryl compounds are important frameworks across a range of fields including pharmaceutical and functional material chemistries. We have accomplished the efficient synthesis of various naphthalene-linked arenes and heteroarenes as biaryls and heterobiaryls by the FeCl3 -catalyzed Friedel-Crafts reactions accompanied by the ring-opening of the 1,4-epoxy moiety of 1,4-epoxy-1,4-dihydronaphthalenes. Especially, it is noteworthy that 1-silylated substrates were regioselectively transformed to the 3-aryl-1-silylnaphthalenes and the double Friedel-Crafts reactions using thiophene derivatives could directly produce the corresponding bis-naphthlated thiophene derivatives.

  2. Investigation of continuous wave and pulsed laser performance based on Nd3+:Gd0.6Y1.4SiO5 crystal

    NASA Astrophysics Data System (ADS)

    Feng, Chao; Liu, Zhaojun; Cong, Zhenhua; Shen, Hongbin; Li, Yongfu; Wang, Qingpu; Fang, Jiaxiong; Xu, Xiaodong; Xu, Jun; Zhang, Xingyu

    2015-12-01

    We systematically investigated a laser diode (LD) pumped Nd:GYSO (Nd3+:Gd0.6Y1.4SiO5) laser. The output power of the continuous wave laser was as high as 3.5 W with a slope efficiency of 31.8%. In the Q-switched operation; the laser exhibited dual-wavelengths output (1073.6 nm and 1074.7 nm) synchronously with a Cr4+:YAG as the saturable absorber (SA). Additionally, a passively mode-locked laser was demonstrated using a semiconductor SA mirror with a maximum average output power of 510 mW at a central wavelength of 1074 nm, while the pulse width of the laser was as short as 5 ps. Our experiment proved that the Nd:GYSO mixed crystal was a promising material for a solid-state laser.

  3. Proton-proton Scattering Above 3 GeV/c

    SciTech Connect

    A. Sibirtsev, J. Haidenbauer, H.-W. Hammer S. Krewald ,Ulf-G. Meissner

    2010-01-01

    A large set of data on proton-proton differential cross sections, analyzing powers and the double-polarization parameter A{sub NN} is analyzed employing the Regge formalism. We find that the data available at proton beam momenta from 3 GeV/c to 50 GeV/c exhibit features that are very well in line with the general characteristics of Regge phenomenology and can be described with a model that includes the {rho}, {omega}, f{sub 2}, and a{sub 2} trajectories and single-Pomeron exchange. Additional data, specifically for spin-dependent observables at forward angles, would be very helpful for testing and refining our Regge model.

  4. High-power proton linac for transmuting the long-lived fission products in nuclear waste

    SciTech Connect

    Lawrence, G.P.

    1991-01-01

    High power proton linacs are being considered at Los Alamos as drivers for high-flux spallation neutron sources that can be used to transmute the troublesome long-lived fission products in defense nuclear waste. The transmutation scheme being studied provides a high flux (> 10{sup 16}/cm{sup 2}{minus}s) of thermal neutrons, which efficiently converts fission products to stable or short-lived isotopes. A medium-energy proton linac with an average beam power of about 110 MW can burn the accumulated Tc99 and I129 inventory at the DOE's Hanford Site within 30 years. Preliminary concepts for this machine are described. 3 refs., 5 figs., 2 tabs.

  5. Measurement of the Wolfenstein parameters for proton-proton and proton-neutron scattering at 500 MeV

    SciTech Connect

    Marshall, J.A.

    1984-07-01

    Using liquid hydrogen and liquid deuterium targets respectively, forward angle (ten degrees to sixty degrees in the center of Mass) free proton-proton and quasielastic proton-proton and proton-neutron triple scattering data at 500 MeV have been obtained using the high resolution spectrometer at the Los Alamos Meson Physics Facility. The data are in reasonable agreement with recent predictions from phase shift analyses, indicating that the proton-nucleon scattering amplitudes are fairly well determined at 500 MeV. 32 references.

  6. Explaining the Cyclic Voltammetry of a Poly(1,4-phenylene-ethynylene)-alt-poly(1,4-phenylene-vinylene) Copolymer upon Oxidation by using Spectroscopic Techniques.

    PubMed

    Enengl, Christina; Enengl, Sandra; Bouguerra, Nassima; Havlicek, Marek; Neugebauer, Helmut; Egbe, Daniel A M

    2017-01-04

    Poly(1,4-phenylene-ethynylene)-alt-poly(1,4-phenylene-vinylene) (PPE-PPV) copolymers have attracted quite a lot of attention in the last few years for electronic device applications owing to their enhanced fluorescence. In this work, we focus on one particular PPE-PPV copolymer with dissymmetrically substituted 1,4-phenylene-ethynylene and symmetrically substituted 1,4-phenylene-vinylene building units. Six successively performed cyclic voltammograms are presented, measured during the oxidation reactions. As the oxidation onset of the electrochemical reaction shifts to lower potentials in each cycle, this behavior is elucidated by using spectroscopic techniques ranging from UV/Vis/near-IR to mid-IR including spin-resonance techniques. Hence, these findings help to explain some of the copolymer's most advantageous properties in terms of possible oxidation products.

  7. Bio-activation of 4-alkyl analogs of 1,4-dihydropyridine mediated by cytochrome P450 enzymes.

    PubMed

    Li, Xiao-Xi; Zhang, Xiaoqian; Zheng, Qing-Chuan; Wang, Yong

    2015-06-01

    4-Alkyl-substituted 1,4-dihydropyridines (DHP) exhibit inhibitory activity toward certain cytochrome P450 enzymes (P450) during their biotransformation by these enzymes, which is called mechanism-based inactivation. Though much experimental evidence had proved the essentiality of alkyl radical for P450 inactivation, the underlying mechanism of such radical formation remains elusive. In the present study, density functional calculations were employed to investigate the dealkylation mechanism of 4-alkyl-substituted DHPs mediated by P450. Interestingly, our results indicate that the initial N-H activation proceeds via a proton-coupled electron transfer process, not via the long presumed hydrogen atom transfer mechanism or the stepwise electron transfer/proton transfer one, to form the amino radical and Cpd II complex. Subsequently, homolytic C-C bond cleavage at the 4-position occurs to afford the product complex involving an alkyl radical, an aromatic pyridine derivative. This C-C cleavage step is rate determining for the whole metabolic reaction, with an energy barrier of 7.9/7.9 kcal/mol on the quartet/doublet state, to which aromatization contributes as an essential intrinsic driving force. The 4-substituent groups induce differences in activation energy barriers and in the transition state structures of hydrogen abstraction process. The substrate reactivity correlates well with the stability of the generated alkyl radical as well as the C-C bond dissociation energy. Understanding the metabolic mechanism of DHP analogs is indeed essential for the related design of safer and more efficient drugs. Furthermore, our findings also enrich the mechanistic picture of amine oxidation catalyzed by P450.

  8. The Spin of the Proton

    SciTech Connect

    Thomas, Anthony

    2008-07-01

    doi: http://dx.doi.org/10.1016/j.ppnp.2007.12.039
    The twenty years since the announcement of the proton spin crisis by the European Muon Collaboration has seen tremendous progress in our knowledge of the distribution of spin within the proton. The problem is reviewed, beginning with the original data and the suggestion that polarized gluons may play a crucial role in resolving the problem through the U(1) axial anomaly. The discussion continues to the present day where not only have strong limits have been placed on the amount of polarized glue in the proton but the experimental determination of the spin content has become much more precise. It is now clear that the origin of the discrepancy between experiment and the naive expectation of the fraction of spin carried by the quarks and anti-quarks in the proton lies in the non-perturabtive structure of the proton. We explain how the features expected in a modern, relativistic and chirally symmetric description of nucleon str

  9. The Structure of the Proton

    DOE R&D Accomplishments Database

    Chambers, E. E.; Hofstadter, R.

    1956-04-01

    The structure and size of the proton have been studied by means of the methods of high-energy electron scattering. The elastic scattering of electrons from protons in polyethylene has been investigated at the following energies in the laboratory system: 200, 300, 400, 500, 550 Mev. The range of laboratory angles examined has been 30 degrees to 135 degrees. At the largest angles and the highest energy, the cross section for scattering shows a deviation below that expected from a point proton by a factor of about nine. The magnitude and variation with angle of the deviations determine a structure factor for the proton, and thereby determine the size and shape of the charge and magnetic-moment distributions within the proton. An interpretation, consistent at all energies and angles and agreeing with earlier results from this laboratory, fixes the rms radius at 0.77 {plus or minus} 0.10 x 10{sup -13} cm for each of the charge and moment distributions. The shape of the density function is not far from a Gaussian with rms radius 0.70 x 10{sup -13} cm or an exponential with rms radius 0.80 x 10 {sup -13} cm. An equivalent interpretation of the experiments would ascribe the apparent size to a breakdown of the Coulomb law and the conventional theory of electromagnetism.

  10. Development of a 2 MW CW Waterload for Electron Cyclotron Heating Systems

    SciTech Connect

    R. Lawrence,Ives; Maxwell Mizuhara; George Collins; Jeffrey Neilson; Philipp Borchard

    2012-11-09

    Calabazas Creek Research, Inc. developed a load capable of continuously dissipating 2 MW of RF power from gyrotrons. The input uses HE11 corrugated waveguide and a rotating launcher to uniformly disperse the power over the lossy surfaces in the load. This builds on experience with a previous load designed to dissipate 1 MW of continuous RF power. The 2 MW load uses more advanced RF dispersion to double the capability in the same size device as the 1 MW load. The new load reduces reflected power from the load to significantly less than 1 %. This eliminates requirements for a preload to capture reflected power. The program updated control electronics that provides all required interlocks for operation and measurement of peak and average power. The program developed two version of the load. The initial version used primarily anodized aluminum to reduce weight and cost. The second version used copper and stainless steel to meet specifications for the ITER reactor currently under construction in France. Tests of the new load at the Japanese Atomic Energy Agency confirmed operation of the load to a power level of 1 MW, which is the highest power currently available for testing the load. Additional tests will be performed at General Atomics in spring 2013. The U.S. ITER organization will test the copper/stainless steel version of the load in December 2012 or early in 2013. Both loads are currently being marketed worldwide.

  11. Structural Considerations of a 20MW Multi-Rotor Wind Energy System

    NASA Astrophysics Data System (ADS)

    Jamieson, P.; Branney, M.

    2014-12-01

    The drive to upscale offshore wind turbines relates especially to possiblereductions in O&M and electrical interconnection costs per MW of installed capacity.Even with best current technologies, designs with rated capacity above about 3 MW are less cost effective exfactory per rated MW(turbine system costs) than smaller machines.Very large offshore wind turbines are thereforejustifiedprimarily by overall offshore project economics. Furthermore, continuing progress in materials and structures has been essential to avoid severe penalties in the power/mass ratio of large multi-MW machines.The multi-rotor concept employs many small rotors to maximise energy capture area withminimum systemvolume. Previous work has indicated that this can enablea very large reduction in the total weight and cost of rotors and drive trains compared to an equivalent large single rotor system.Thus the multi rotor concept may enable rated capacities of 20 MW or more at a single maintenancesite. Establishing the cost benefit of a multi rotor system requires examination of solutions for the support structure and yawing, ensuring aerodynamic losses from rotor interaction are not significant and that overall logistics, with much increased part count (more reliable components) and less consequence of single failuresare favourable. This paper addresses the viability of a support structure in respect of structural concept and likely weight as one necessary step in exploring the potential of the multi rotor concept.

  12. Status of KSTAR 170 GHz, 1 MW Electron Cyclotron Heating and Current Drive System

    SciTech Connect

    Joung, M.; Bae, Y. S.; Jeong, J. H.; Park, S.; Kim, H. J.; Yang, H. L.; Park, H.; Cho, M. H.; Namkung, W.; Hosea, J.; Ellis, R.; Sakamoto, K.; Kajiwara, K.; Doane, J.

    2011-12-23

    A 170 GHz Electron Cyclotron Heating and Current Drive (ECH/CD) system on KSTAR is designed to launch total 2.4 MW of power for up to 300 sec into the plasma. At present the first 1 MW ECH/CD system is under installation and commissioning for 2011 KSTAR campaign. The 170 GHz, 1 MW, 300 sec gyrotron and the matching optics unit (MOU) will be provided from JAEA under collaboration between NFRI and JAEA. The transmission line consists of MOU and 70 m long 63.5 mm ID corrugated waveguides with the eight miter bends. The 1 MW, 10 sec launcher is developed based on the existing two-mirror front-end launcher in collaboration with Princeton Plasma Physics Laboratory and Pohang University of Science and Technology, and is installed on the low field side in the KSTAR equatorial plane. The mirror pivot is located at 30 cm below from the equatorial plane. 3.6 MVA power supply system is manufactured and now is under commissioning to meet the triode gun operation of JAEA gyrotron. The power supply consists of 66 kV/55 A cathode power supply, mode-anode system, and 50 kV/160 mA body power supply. In this paper, the current status of KSTAR 170 GHz, 1 MW ECH/CD system will be presented as well as the experimental plan utilizing 170 GHz new ECH/CD system.

  13. Comparative study of two tsunamigenic earthquakes in the Solomon Islands: 2015 Mw 7.0 normal-fault and 2013 Santa Cruz Mw 8.0 megathrust earthquakes

    NASA Astrophysics Data System (ADS)

    Heidarzadeh, Mohammad; Harada, Tomoya; Satake, Kenji; Ishibe, Takeo; Gusman, Aditya Riadi

    2016-05-01

    The July 2015 Mw 7.0 Solomon Islands tsunamigenic earthquake occurred ~40 km north of the February 2013 Mw 8.0 Santa Cruz earthquake. The proximity of the two epicenters provided unique opportunities for a comparative study of their source mechanisms and tsunami generation. The 2013 earthquake was an interplate event having a thrust focal mechanism at a depth of 30 km while the 2015 event was a normal-fault earthquake occurring at a shallow depth of 10 km in the overriding Pacific Plate. A combined use of tsunami and teleseismic data from the 2015 event revealed the north dipping fault plane and a rupture velocity of 3.6 km/s. Stress transfer analysis revealed that the 2015 earthquake occurred in a region with increased Coulomb stress following the 2013 earthquake. Spectral deconvolution, assuming the 2015 tsunami as empirical Green's function, indicated the source periods of the 2013 Santa Cruz tsunami as 10 and 22 min.

  14. Rupture processes of the 28 October 2012 (Mw 7.7) and 5 January 2013 (Mw 7.6) earthquakes along the Queen Charlotte Fault system (South Alaska)

    NASA Astrophysics Data System (ADS)

    Atakan, Kuvvet; Raeesi, Mohammad

    2013-04-01

    The plate boundary linking the Alaska and Cascadia subduction zones is known as an oceanic transform fault system, called Queen Charlotte. However, the bathymetry along the system shows a trench-like structure. Two major earthquakes with different mechanisms ruptured two segments of the system about 200 km apart. The 28 October 2012 (Mw 7.7) event has a high-angle thrust mechanism, while the 5 January 2013 (Mw 7.6) earthquake has a pure strike-slip mechanism. We analyze these two earthquakes through body-waveform inversion and a gravity-derived anomaly, "Trench Parallel Bouguer Anomaly" (TPBA). TPBA can be used for detecting asperities of earthquakes along forearc settings independent of the earthquake. A likely scenario for these two events will be presented.

  15. Estimation of - and Postseismic Deformation after the mw 8.6 Nias-Semeulue and mw 8.5 Bengkulu Earthquakes from Continuous GPS Data

    NASA Astrophysics Data System (ADS)

    Aris, W. A. W.; Musa, T. A.; Omar, K.

    2016-09-01

    The Mw 8.5 Bengkulu earthquake of 30 September 2007 and the Mw8.6 28 March 2005 are considered amongst large earthquake ever recorded in Southeast Asia. The impact into tectonic deformation was recorded by a network of Global Positioning System (GPS) Continuously Operating Reference Station (CORS) within southern of Sumatra and west-coast of Peninsular Malaysia. The GPS data from the GPS CORS network has been deployed to investigate the characteristic of postseismic deformation due to the earthquakes. Analytical logarithmic and exponential function was applied to investigate the deformation decay period of postseismic deformation. This investigation provides a preliminary insight into postseismic cycle along the Sumatra subduction zone in particular and on the dynamics Peninsular Malaysia in general.

  16. Proton therapy for Hodgkin lymphoma.

    PubMed

    Rutenberg, Michael S; Flampouri, Stella; Hoppe, Bradford S

    2014-09-01

    Hodgkin lymphoma has gone from an incurable disease to one for which the majority of patients will be cured. Combined chemotherapy and radiotherapy achieves the best disease control rates and results in many long-term survivors. As a result, a majority of long-term Hodgkin lymphoma survivors live to experience severe late treatment-related complications, especially cardiovascular disease and second malignancies. The focus of research and treatment for Hodgkin lymphoma is to maintain the current high rates of disease control while reducing treatment-related morbidity and mortality. Efforts to reduce late treatment complications focus on improvements in both systemic therapies and radiotherapy. Herein we review the basis for the benefits of proton therapy over conventional X-ray therapy. We review outcomes of Hodgkin lymphoma treated with proton therapy, and discuss the ability of protons to reduce radiation dose to organs at risk and the impact on the most significant late complications related to the treatment.

  17. Metal-organic frameworks from copper dimers with cis- and trans-1,4-cyclohexanedicarboxylate and cis,cis-1,3,5-cyclohexanetricarboxylate.

    PubMed

    Kumagai, Hitoshi; Akita-Tanaka, Motoko; Inoue, Katsuya; Takahashi, Kazuyuki; Kobayashi, Hayao; Vilminot, Serge; Kurmoo, Mohamedally

    2007-07-23

    Single crystals of three coordination networks containing the Cu(2)(COO)(4) core bridged by cyclohexane have been hydrothermally prepared by the reaction of 1,4-cyclohexanedicarboxylic (1,4-H(2)chdc) or 1,3,5-cyclohexanetricarboxylic (1,3,5-H(3)chtc) acid and Cu(NO(3))(2) x 6H(2)O. We report their characterizations by single-crystal X-ray structure determinations, IR spectroscopy, thermal analyses, and their magnetic properties. [Cu(2)(trans-1,4-chdc)(2)] (1) consists of 4 x 4 grids with the dimeric nodes connected by the trans-1,4-chdc, and these grids are then connected to each other by Cu-O bonds, resulting in a porous network (void volume of 130 Angstrom(3) per cell or 25%) with no solvent in its cavities. [Cu(2)(cis-1,4-chdc)(2)(H(2)O)(2)] (2) consists of two-legged ladders where the dimer nodes are bridged by pairs of cis-1,4-chdc and the water molecules cap the ends of the Cu dimers. [Cu(2)(1,3,5-Hchtc)(2)] (3) displays 4 x 4 grids, but each dimeric node is connected to its neighbors within the same grid by Cu-O bonds to form a layered network which further makes hydrogen-bond interactions with its neighbors. 2 and 3 have compact structures without any space for solvents. IR and DT-TGA confirm the absence of water in the empty channels of 1, while IR shows the presence of both protonated and deprotonated carboxyl groups for 3. The magnetic properties of all three compounds are dominated by the strong Cu-Cu antiferromagnetic interaction resulting in singlet-triplet gaps of 450-500 K.

  18. Magnetic field observations in the near-field the 28 June 1992 Mw 7.3 Landers, California, earthquake

    USGS Publications Warehouse

    Johnston, M.J.; Mueller, R.J.; Sasai, Yoichi

    1994-01-01

    Recent reports suggest that large magnetic field changes occur prior to, and during, large earthquakes. Two continuously operating proton magnetometers, LSBM and OCHM, at distances of 17.3 and 24.2 km, respectively, from the epicenter of the 28 June 1992 Mw 7.3 Landers earthquake, recorded data through the earthquake and its aftershocks. These two stations are part of a differentially connected array of proton magnetometers that has been operated along the San Andreas fault since 1976. The instruments have a sensitivity of 0.25 nT or better and transmit data every 10 min through the GOES satellite to the USGS headquarters in Menlo Park, California. Seismomagnetic offsets of −1.2 ± 0.6 and −0.7 ± 0.7 nT were observed at these sites. In comparison, offsets of −0.3 ± 0.2 and −1.3 ± 0.2 nT were observed during the 8 July 1986 ML 5.9 North Palm Springs earthquake, which occurred directly beneath the OCHM magnetometer site. The observations are generally consistent with seismomagnetic models of the earthquake, in which fault geometry and slip have the same from as that determined by either inversion of the seismic data or inversion of geodetically determined ground displacements produced by the earthquake. In these models, right-lateral rupture occurs on connected fault segments in a homogeneous medium with average magnetization of 2 A/m. The fault-slip distribution has roughly the same form as the observed surface rupture, and the total moment release is 1.1 × 1020 Nm. There is no indication of diffusion-like character to the magnetic field offsets that might indicate these effects result from fluid flow phenomena. It thus seems unlikely that these earthquake-generated offsets and those produced by the North Palm Springs earthquake were generated by electrokinetic effects. Also, there are no indications of enhanced low-frequency magnetic noise before the earthquake at frequencies below 0.001 Hz.

  19. Proton aurora and substorm intensifications

    NASA Technical Reports Server (NTRS)

    Samson, J. C.; Xu, B.; Lyons, L. R.; Newell, P. T.; Creutzberg, F.

    1993-01-01

    Ground based measurements from the CANOPUS array of meridian scanning photometers and precipitating ion and electron data from the DMSP F9 satellite show that the electron arc which brightens to initiate substorm intensifications is formed within a region of intense proton precipitation that is well equatorward (approximately four to six degrees) of the nightside open-closed field line boundary. The precipitating protons are from a population that is energized via earthward convection from the magnetotail into the dipolar region of the magnetosphere and may play an important role in the formation of the electron arcs leading to substorm intensifications on dipole-like field lines.

  20. Search for sphalerons in proton-proton collisions

    NASA Astrophysics Data System (ADS)

    Ellis, John; Sakurai, Kazuki

    2016-04-01

    In a recent paper, Tye and Wong (TW) have argued that sphaleron-induced transitions in high-energy proton-proton collisions should be enhanced compared to previous calculations, based on a construction of a Bloch wave function in the periodic sphaleron potential and the corresponding pass band structure. Here we convolute the calculations of TW with parton distribution functions and simulations of final states to explore the signatures of sphaleron transitions at the LHC and possible future colliders. We calculate the increase of sphaleron transition rates in proton-proton collisions at centre-of-mass energies of 13/14/33/100 TeV for different sphaleron barrier heights, while recognising that the rates have large overall uncertainties. We use a simulation to show that LHC searches for microscopic black holes should have good efficiency for detecting sphaleron-induced final states, and discuss their experimental signatures and observability in Run 2 of the LHC and beyond. We recast the early ATLAS Run-2 search for microscopic black holes to constrain the rate of sphaleron transitions at 13 TeV, deriving a significant limit on the sphaleron transition rate for the nominal sphaleron barrier height of 9 TeV.

  1. Extension of Gutenberg-Richter distribution to Mw -1.3, no lower limit in sight

    USGS Publications Warehouse

    Boettcher, M.S.; McGarr, A.; Johnston, M.

    2009-01-01

    [1] With twelve years of seismic data from TauTona Gold Mine, South Africa, we show that mining-induced earthquakes follow the Gutenberg-Richter relation with no scale break down to the completeness level of the catalog, at moment magnitude Mw -1.3. Events recorded during relatively quiet hours in 2006 indicate that catalog detection limitations, not earthquake source physics, controlled the previously reported minimum magnitude in this mine. Within the Natural Earthquake Laboratory in South African Mines (NELSAM) experiment's dense seismic array, earthquakes that exhibit shear failure at magnitudes as small as Mw -3.9 are observed, but we find no evidence that Mw -3.9 represents the minimum magnitude. In contrast to previous work, our results imply small nucleation zones and that earthquake processes in the mine can readily be scaled to those in either laboratory experiments or natural faults.

  2. Deevelopment of a 1.5 MW, 140 GHz coaxial gyrotron

    SciTech Connect

    Piosczyk, B.; Dammertz, G.; Iatrou, C.T.; Moebius, A.; Zhang, S.C.

    1995-12-31

    A 1.5 MW, 140 GHz, TE{sub 28,16}-coaxial gyrotron with an inverse MIG is under development. Preliminary rf-tests using an axial rf output and a simple cavity with a constant diameter and non-corrugated inner rod gave an rf output power of 1 MW with an efficiency of 23% at 140 GHz (TE{sub 28,16}) and 1.3 MW with an efficiency of 29% at 133 GHz (TE{sup 27,15}). No indications of beam instabilities in the beam tunnel between the IMIG gun and the cavity have been observed. Experiments with an improved cavity and the design of the tube with a radial dual Gaussian beam output and a depressed collector are underway.

  3. Revisiting the Canterbury earthquake sequence after the 14 February 2016 Mw 5.7 event

    NASA Astrophysics Data System (ADS)

    Herman, Matthew W.; Furlong, Kevin P.

    2016-07-01

    On 14 February 2016, an Mw 5.7 (GNS Science moment magnitude) earthquake ruptured offshore east of Christchurch, New Zealand. This earthquake occurred in an area that had previously experienced significant seismicity from 2010 to 2012 during the Canterbury earthquake sequence, starting with the 2010 Mw 7.0 Darfield earthquake and including four Mw ~6.0 earthquakes near Christchurch. We determine source parameters for the February 2016 event and its aftershocks, relocate the recent events along with the Canterbury earthquakes, and compute Coulomb stress changes resolved onto the recent events and throughout the greater Christchurch region. Because the February 2016 earthquake occurred close to previous seismicity, the Coulomb stress changes resolved onto its nodal planes are uncertain. However, in the greater Christchurch region, there are areas that remain positively loaded, including beneath the city of Christchurch. The recent earthquake and regional stress changes suggest that faults in these regions may pose a continuing seismic hazard.

  4. Economic Development Impact of 1,000 MW of Wind Energy in Texas

    SciTech Connect

    Reategui, S.; Hendrickson, S.

    2011-08-01

    Texas has approximately 9,727 MW of wind energy capacity installed, making it a global leader in installed wind energy. As a result of the significant investment the wind industry has brought to Texas, it is important to better understand the economic development impacts of wind energy in Texas. This report analyzes the jobs and economic impacts of 1,000 MW of wind power generation in the state. The impacts highlighted in this report can be used in policy and planning decisions and can be scaled to get a sense of the economic development opportunities associated with other wind scenarios. This report can also inform stakeholders in other states about the potential economic impacts associated with the development of 1,000 MW of new wind power generation and the relationships of different elements in the state economy.

  5. Calculational criticality analyses of 10- and 20-MW UF[sub 6] freezer/sublimer vessels

    SciTech Connect

    Jordan, W.C.

    1993-02-01

    Calculational criticality analyses have been performed for 10- and 20-MW UF[sub 6] freezer/sublimer vessels. The freezer/sublimers have been analyzed over a range of conditions that encompass normal operation and abnormal conditions. The effects of HF moderation of the UF[sub 6] in each vessel have been considered for uranium enriched between 2 and 5 wt % [sup 235]U. The results indicate that the nuclearly safe enrichments originally established for the operation of a 10-MW freezer/sublimer, based on a hydrogen-to-uranium moderation ratio of 0.33, are acceptable. If strict moderation control can be demonstrated for hydrogen-to-uranium moderation ratios that are less than 0.33, then the enrichment limits for the 10-MW freezer/sublimer may be increased slightly. The calculations performed also allow safe enrichment limits to be established for a 20-NM freezer/sublimer under moderation control.

  6. Foreshock triggering of the 1 April 2014 Mw 8.2 Iquique, Chile, earthquake

    NASA Astrophysics Data System (ADS)

    Herman, Matthew W.; Furlong, Kevin P.; Hayes, Gavin P.; Benz, Harley M.

    2016-08-01

    On April 1st, 2014, a Mw 8.2 (U.S. Geological Survey moment magnitude) earthquake occurred in the subduction zone offshore northern Chile. In the two weeks leading up to the earthquake, a sequence of foreshocks, starting with a Mw 6.7 earthquake on March 16th and including three more Mw 6.0+ events, occurred predominantly south of the April 1st mainshock epicenter and up-dip of the area of significant slip during the mainshock. Using earthquake locations and source parameters derived in a previous study (Hayes et al., 2014) and a Coulomb failure stress change analysis of these events, we assess in detail the hypothesis that the earthquakes occurred as a cascading sequence, each event successively triggering the next, ultimately triggering the rupture of the mainshock. Following the initial Mw 6.7 event, each of the three largest foreshocks (Mw 6.4, 6.2 and 6.3), as well as the hypocenter of the mainshock, occurred in a region of positive Coulomb stress change produced by the preceding events, indicating these events were brought closer to failure by the prior seismicity. In addition, we reexamine the possibility that aseismic slip occurred and what role it may have played in loading the plate boundary. Using horizontal GPS displacements from along the northern Chile coast prior to the mainshock, we find that the foreshock seismicity alone likely does not account for the observed signals. We perform a grid search for the location and magnitude of an aseismic slip patch that can account for the difference between observed signals and foreshock-related displacement, and find that a slow slip region with slip corresponding to a Mw ∼ 6.8 earthquake located coincident with or up-dip of the foreshock seismicity can best explain this discrepancy. Additionally, such a slow slip region positively loads the mainshock hypocentral area, enhancing the positive loading produced by the foreshock seismicity.

  7. DIII-D electron cyclotron heating 2 MW upgrade project. Final report, FY1989--FY1997

    SciTech Connect

    Callis, R.W.

    1997-08-01

    The 2 MW, 110 GHz ECH system was based on the General Atomics Proposal to the Department of Energy: DIII-D Fusion Research Program Vol. I Technical, and Vol. II Cost (GACP-72-166, July 1987 and revised). This proposal was reviewed in August 1987 by a senior technical review committee, who recommended to vigorously pursue increasing the ECH power to 6 MW. The realization of the higher frequency and power ECH on DIII-D was recognized by the committee to be important, not only for the DIII-D program, but also for future devices and the whole ECH area. Subsequently, an engineering cost and schedule review was conducted by DOE-OAK which confirmed the GA costs and schedules and recommended proceeding directly to 10 MW. However, because of budgetary constraints, in the April 1988 Field Task Proposal submission, GA proposed a phased ECH approach, Phase I being 2 MW and Phase II increasing the power to 10 MW. After review, DOE instructed GA to initiate the prototype 2 MW, 110 GHz program. The contract to procure four 500 kW, 110 GHz, 10 s gyrotrons from Varian Associates was initiated in April 1989 with final delivery by November 1990. Because of difficulties in spreading the energy of the electron beam over the collector area, the testing of the first gyrotron delayed its delivery until February 1991. The second gyrotron was able to operate for 1 s at 500 kW and 2 s at 300 kW, but failed when the cavity suffered thermal damage.

  8. INJECTION ACCELERATION AND EXTRACTION OF HIGH INTENSITY PROTON BEAM FOR THE NEUTRINO FACILITY PROJECT AT BNL.

    SciTech Connect

    Tsoupas, N; Barton, D; Ganetis, G; Jain, A; Lee, Y; Marneris, I; Meng, W; Raparia, D; Roser, T; Ruggiero, A; Tuozzolo, J; Wanderer, P; Weng, W

    2003-05-12

    The proposed ''neutrino-production'' project [1.2] to be built at the Brookhaven National Laboratory (BNL) requires that the neutrino-production target be bombarded by a high intensity proton beam-pulse of {approx} 90 x 10{sup 12} protons of 28 GeV in energy and at a rate of 2.5 Hz, resulting in a 1 MW power of proton beam deposited on the target for the production of the neutrinos. In this paper we investigate the possibility of producing this high intensity proton beam, using as the main accelerator the Alternating Gradient Synchrotron (AGS) at the Brookhaven National Laboratory (BNL). The following aspects of the project are reported in this paper: (a) The beam injection into the AGS synchrotron of 1.2 GeV H{sup -} beam produced by a super-conducting LINAC[3]; (b) The effect of the eddy currents induced on the vacuum chamber of the circulating beam during the ''ramping'' of the main magnets of the AGS; (c) The method of the beam extraction from the AGS and the optics of the 28 GeV beam extracted from the AGS.

  9. An Alpha Proton X-Ray Spectrometer for Mars-96 and Mars Pathfinder

    NASA Astrophysics Data System (ADS)

    Rieder, R.; Wanke, H.; Economou, T.

    1996-09-01

    Mars Pathfinder and the Russian Mars-96 will carry an Alpha Proton X-Ray Spectrometer (APXS) for the determination of the chemical composition of Martian rocks and soil. The instrument will measure the concentration of all major and many minor elements, including C,N and O, at levels above typically 1%. The method employed consist of bombarding a sample of 50 mm diameter with alpha particles from a radioactive source (50 mCi of Cm-244) and measuring: (i) backscattered alpha particles (alpha mode) (ii) protons from (a,p) reactions with some light elements (proton mode) (iii) characteristic X-rays emitted from the sample (X-ray mode). The APXS has a long standing space heritage, going back to Surveyor V,VI and VII (1967/68) and the Soviet Phobos (1988) missions. The present design is the result of an endeavour to reduce mass and power consumption to 600g/ 300mW. It consist of a sensor head containing the alpha sources, a telescope of a silicon detectors for the detection of the alpha particles and protons and a separate X-ray detector with its preamplifier, and an electronics box (80x70x60 mm) containing a microcontroller based multichannel spectrometer. The paper will describe the APXS flight hardware and present results obtained with the flight instrument that will show the instrument capabili- ties and the expected results to be obtained during surface operations on Mars.

  10. Measurement of pion, kaon and proton production in proton-proton collisions at TeV

    NASA Astrophysics Data System (ADS)

    Adam, J.; Adamová, D.; Aggarwal, M. M.; Rinella, G. Aglieri; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmed, I.; Ahn, S. U.; Aimo, I.; Aiola, S.; Ajaz, M.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Molina, R. Alfaro; Alici, A.; Alkin, A.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Prado, C. Alves Garcia; Andrei, C.; Andronic, A.; Anguelov, V.; Anielski, J.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Armesto, N.; Arnaldi, R.; Aronsson, T.; Arsene, I. C.; Arslandok, M.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Bach, M.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Ball, M.; Pedrosa, F. Baltasar Dos Santos; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Camejo, A. Batista; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Martinez, H. Bello; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Belyaev, V.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biswas, S.; Bjelogrlic, S.; Blanco, F.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botje, M.; Botta, E.; Böttger, S.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Buxton, J. T.; Caffarri, D.; Cai, X.; Caines, H.; Diaz, L. Calero; Caliva, A.; Villar, E. Calvo; Camerini, P.; Carena, F.; Carena, W.; Castellanos, J. Castillo; Castro, A. J.; Casula, E. A. R.; Cavicchioli, C.; Sanchez, C. Ceballos; Cepila, J.; Cerello, P.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Barroso, V. Chibante; Chinellato, D. D.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Balbastre, G. Conesa; Valle, Z. Conesa del; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Morales, Y. Corrales; Maldonado, I. Cortés; Cortese, P.; Cosentino, M. R.; Costa, F.; Crochet, P.; Albino, R. Cruz; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; De, S.; Caro, A. De; Cataldo, G. de; Cuveland, J. de; Falco, A. De; Gruttola, D. De; Marco, N. De; Pasquale, S. De; Deisting, A.; Deloff, A.; Dénes, E.; D'Erasmo, G.; Bari, D. Di; Mauro, A. Di; Nezza, P. Di; Corchero, M. A. Diaz; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Dobrowolski, T.; Gimenez, D. Domenicis; Dönigus, B.; Dordic, O.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Engel, H.; Erazmus, B.; Erhardt, F.; Eschweiler, D.; Espagnon, B.; Estienne, M.; Esumi, S.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Felea, D.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Téllez, A. Fernández; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fuchs, U.; Furget, C.; Furs, A.; Girard, M. Fusco; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Germain, M.; Gheata, A.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Dziadus, E. Gladysz; Glässel, P.; Ramirez, A. Gomez; Zamora, P. González; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Graczykowski, L. K.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gulkanyan, H.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hanratty, L. D.; Hansen, A.; Harris, J. W.; Hartmann, H.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Heide, M.; Helstrup, H.; Herghelegiu, A.; Corral, G. Herrera; Hess, B. A.; Hetland, K. F.; Hilden, T. E.; Hillemanns, H.; Hippolyte, B.; Hristov, P.; Huang, M.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Ilkiv, I.; Inaba, M.; Ionita, C.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacobs, P. M.; Jahnke, C.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Bustamante, R. T. Jimenez; Jones, P. G.; Jung, H.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kamin, J.; Kang, J. H.; Kaplin, V.; Kar, S.; Uysal, A. Karasu; Karavichev, O.; Karavicheva, T.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Khan, K. H.; Khan, M. M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, B.; Kim, D. W.; Kim, D. J.; Kim, H.; Kim, J. S.; Kim, M.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobayashi, T.; Kobdaj, C.; Kofarago, M.; Köhler, M. K.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Kox, S.; Meethaleveedu, G. Koyithatta; Kral, J.; Králik, I.; Kravčáková, A.; Krelina, M.; Kretz, M.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kucheriaev, Y.; Kugathasan, T.; Kuhn, C.; Kuijer, P. G.; Kulakov, I.; Kumar, J.; Kumar, L.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kushpil, S.; Kweon, M. J.; Kwon, Y.; Pointe, S. L. La; Rocca, P. La; Fernandes, C. Lagana; Lakomov, I.; Langoy, R.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, G. R.; Lee, S.; Legrand, I.; Lehnert, J.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; Monzón, I. León; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loggins, V. R.; Loginov, V.; Loizides, C.; Lopez, X.; Torres, E. López; Lowe, A.; Lu, X.-G.; Luettig, P.; Lunardon, M.; Luparello, G.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Cervantes, I. Maldonado; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manceau, L.; Manko, V.; Manso, F.; Manzari, V.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Blanco, J. Martin; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Pedreira, M. Martinez; Martynov, Y.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Massacrier, L.; Mastroserio, A.; Masui, H.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; Mcdonald, D.; Meddi, F.; Menchaca-Rocha, A.; Meninno, E.; Pérez, J. Mercado; Meres, M.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Minervini, L. M.; Mischke, A.; Mishra, A. N.; Miśkowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Zetina, L. Montaño; Montes, E.; Morando, M.; Godoy, D. A. Moreira De; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Müller, H.; Mulligan, J. D.; Munhoz, M. G.; Murray, S.; Musa, L.; Musinsky, J.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Nattrass, C.; Nayak, K.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Silva, A. C. Oliveira Da; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Velasquez, A. Ortiz; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, P.; Paić, G.; Pajares, C.; Pal, S. K.; Pan, J.; Pandey, A. K.; Pant, D.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Paul, B.; Pawlak, T.; Peitzmann, T.; Costa, H. Pereira Da; Filho, E. Pereira De Oliveira; Peresunko, D.; Lara, C. E. Pérez; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Płoskoń, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Razazi, V.; Read, K. F.; Real, J. S.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reicher, M.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Rettig, F.; Revol, J.-P.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rivetti, A.; Rocco, E.; Cahuantzi, M. Rodríguez; Manso, A. Rodriguez; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Romita, R.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Montero, A. J. Rubio; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salgado, C. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Castro, X. Sanchez; Šándor, L.; Sandoval, A.; Sano, M.; Santagati, G.; Sarkar, D.; Scapparone, E.; Scarlassara, F.; Scharenberg, R. P.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schuchmann, S.; Schukraft, J.; Schulc, M.; Schuster, T.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Seeder, K. S.; Seger, J. E.; Sekiguchi, Y.; Selyuzhenkov, I.; Senosi, K.; Seo, J.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shangaraev, A.; Sharma, A.; Sharma, N.; Shigaki, K.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singha, S.; Singhal, V.; Sinha, B. C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Søgaard, C.; Soltz, R.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; Spacek, M.; Spiriti, E.; Sputowska, I.; Stassinaki, M. Spyropoulou; Srivastava, B. K.; Stachel, J.; Stan, I.; Stefanek, G.; Steinpreis, M.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Sultanov, R.; Šumbera, M.; Symons, T. J. M.; Szabo, A.; Toledo, A. Szanto de; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Takahashi, J.; Tanaka, N.; Tangaro, M. A.; Takaki, J. D. Tapia; Peloni, A. Tarantola; Tariq, M.; Tarzila, M. G.; Tauro, A.; Muñoz, G. Tejeda; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thomas, D.; Tieulent, R.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vajzer, M.; Vala, M.; Palomo, L. Valencia; Vallero, S.; Maarel, J. Van Der; Hoorne, J. W. Van; Leeuwen, M. van; Vanat, T.; Vyvre, P. Vande; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Venaruzzo, M.; Vercellin, E.; Limón, S. Vergara; Vernet, R.; Verweij, M.; Vickovic, L.; Viesti, G.; Viinikainen, J.; Vilakazi, Z.; Baillie, O. Villalobos; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; Haller, B. von; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Vyushin, A.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Wang, Y.; Watanabe, D.; Weber, M.; Weber, S. G.; Wessels, J. P.; Westerhoff, U.; Wiechula, J.; Wikne, J.; Wilde, M.; Wilk, G.; Wilkinson, J.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yaldo, C. G.; Yamaguchi, Y.; Yang, H.; Yang, P.; Yano, S.; Yasnopolskiy, S.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yurchenko, V.; Yushmanov, I.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zhu, X.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.

    2015-05-01

    The measurement of primary , , and production at mid-rapidity ( 0.5) in proton-proton collisions at 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/ for pions, from 0.2 up to 6 GeV/ for kaons and from 0.3 up to 6 GeV/ for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

  11. Genotoxicity of 1,4-benzoquinone and 1,4-naphthoquinone in relation to effects on glutathione and NAD(P)H levels in V79 cells

    SciTech Connect

    Ludewig, G.; Dogra, S.; Glatt, H. )

    1989-07-01

    1,4-Benzoquinone is cytotoxic in V79 Chinese hamster cells and induces gene mutations and micronuclei. The cell-damaging effects of quinones are usually attributed to thiol depletion, oxidation of NAD(P)H, and redox-cycling involving the formation of semiquinone radicals and reactive oxygen species. To elucidate the role of these mechanisms in the genotoxicity of 1,4-benzoquinone, the authors measured various genotoxic effects, cytotoxicity, and the levels of glutathione, NADPH, NADH, and their oxidized forms all in the same experiment. 1,4-Naphthoquinone, which does not induce gene mutations in V79 cells, was investigated for comparative reasons. The quinones had a similar effect on the levels of cofactors. Total glutathione was depleted, but levels of oxidized glutathione were slightly increased. The levels of NADPH and NADH were reduced at high concentrations of the quinones with a simultaneous increase in the levels of NADP{sup +} and NAD{sup +}. Both compounds induced micronuclei, but neither increased the frequency of sister chromatid exchange. Only 1,4-benzoquinone induced gene mutations. They conclude that (a) induction of micronuclei and glutathione depletion by the two quinones are not linked casually, (b) 1,4-benzoquinone induces gene mutations by a mechanism different from oxidative stress and glutathione depletion, and (c) glutathione does not fully protect the cells against the genotoxicity of quinones.

  12. Protons trap NR1/NR2B NMDA receptors in a nonconducting state.

    PubMed

    Banke, Tue G; Dravid, Shashank M; Traynelis, Stephen F

    2005-01-05

    NMDA receptors are highly expressed in the CNS and are involved in excitatory synaptic transmission, as well as synaptic plasticity. Given that overstimulation of NMDA receptors can cause cell death, it is not surprising that these channels are under tight control by a series of inhibitory extracellular ions, including zinc, magnesium, and H+. We studied the inhibition by extracellular protons of recombinant NMDA receptor NR1/NR2B single-channel and macroscopic responses in transiently transfected human embryonic kidney HEK 293 cells using patch-clamp techniques. We report that proton inhibition proceeds identically in the absence or presence of agonist, which rules out the possibility that protonation inhibits receptors by altering coagonist binding. The response of macroscopic currents in excised patches to rapid jumps in pH was used to estimate the microscopic association and dissociation rates for protons, which were 1.4 x 10(9) m(-1) sec(-1) and 110-196 sec(-1), respectively (K(d) corresponds to pH 7.2). Protons reduce the open probability without altering the time course of desensitization or deactivation. Protons appear to slow at least one time constant describing the intra-activation shut-time histogram and modestly reduce channel open time, which we interpret to reflect a reduction in the overall channel activation rate and possible proton-induced termination of openings. This is consistent with a modest proton-dependent slowing of the macroscopic response rise time. From these data, we propose a physical model of proton inhibition that can describe macroscopic and single-channel properties of NMDA receptor function over a range of pH values.

  13. Demonstration of Steady State Operation with 1 MW of 170 GHz gyrotron for ITER

    SciTech Connect

    Kasugai, Atsushi; Takahashi, Koji; Kajiwara, Ken; Kobayashi, Noriyuki; Sakamoto, Keishi

    2007-09-28

    A quasi-steady-state operation of 1 MW/800 s with the efficiency of 55%, which exceeded 1 MW/500 s/50% of the performance required in ITER, was demonstrated in a 170 GHz gyrotron. The oscillation characteristics in the long pulse operation was clarified, and the operation scenario to the hard self-excitation region for the high efficiency oscillation was newly established by controlling a pitch factor of the electron and the cavity magnetic field during the pulse with fixed beam voltage in the triode MIG. The result gives a clear outlook for the success of ECH and ECCD in ITER.

  14. Failure of self-similarity for large (Mw > 81/4) earthquakes.

    USGS Publications Warehouse

    Hartzell, S.H.; Heaton, T.H.

    1988-01-01

    Compares teleseismic P-wave records for earthquakes in the magnitude range from 6.0-9.5 with synthetics for a self-similar, omega 2 source model and conclude that the energy radiated by very large earthquakes (Mw > 81/4) is not self-similar to that radiated from smaller earthquakes (Mw < 81/4). Furthermore, in the period band from 2 sec to several tens of seconds, it is concluded that large subduction earthquakes have an average spectral decay rate of omega -1.5. This spectral decay rate is consistent with a previously noted tendency of the omega 2 model to overestimate Ms for large earthquakes.-Authors

  15. Infrared Applications of Semiconductors II: Symposium Held in Boston, Massachusetts on December 1-4, 1997

    DTIC Science & Technology

    1997-12-01

    Medlin, and R.B. James ’Invited Paper VII Mapping of Large-Area Cadmium Zinc Telluride ( CZT ) Wafers: Apparatus and Methods 253 B.A. Bwnett, J.M...films.11 C075 on CZT (100)4 deg. to (111 )B; Size: 2.5 cm x 1.5 cm 47.9 45.9 43.7 47.4 46.4 41.2 47.5MP-2 71 43.8 43.4 43.7 58.8 45.2...LJ-,-H 15 20 Depth (\\im) MW N-type SW P-type CZT + 25 30 35 Figure 7. EPD depth profile in an MOVPE p-n-N-P LW/MW double-heterojunction

  16. 49 CFR 173.65 - Exceptions for Division 1.4G consumer fireworks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Exceptions for Division 1.4G consumer fireworks... Class 1 § 173.65 Exceptions for Division 1.4G consumer fireworks. (a) Notwithstanding the requirements of §§ 173.56(b), 173.56(f), 173.56(i), and 173.64, Division 1.4G consumer fireworks may be...

  17. 49 CFR 173.65 - Exceptions for Division 1.4G consumer fireworks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Exceptions for Division 1.4G consumer fireworks... Class 1 § 173.65 Exceptions for Division 1.4G consumer fireworks. (a) Notwithstanding the requirements of §§ 173.56(b), 173.56(f), 173.56(i), and 173.64, Division 1.4G consumer fireworks may be...

  18. Effect of bis-1,4-dihydropyridine in the kidney of diabetic rats.

    PubMed

    Gómez-Pliego, Raquel; Gómez-Zamudio, Jaime; Velasco-Bejarano, Benjamín; Ibarra-Barajas, Maximiliano; Villalobos-Molina, Rafael

    2013-01-01

    The in vivo effectiveness of 4-dihydropyridine (bis-1,4-DHP), a new calcium-channel blocker, as a nephroprotector in isolated perfused kidney was evaluated by determining its effects on parameters associated with renal injury in diabetic rats. Diabetes in male Wistar rats, control, diabetic, control + bis-1,4-DHP, and diabetic + bis-1,4-DHP, was induced by a single administration of STZ (55 mg·kg(-1), i.p.). In the drug-treated groups, treatment with bis-1,4-DHP (10 mg·kg(-1)·day(-1)) started one week before diabetes induction; bis-1,4-DHP was dissolved in DMSO (0.3%) and suspended in drinking water with carboxymethyl cellulose (3%). Parameters evaluated were body weight, blood glucose, albuminuria, proteinuria, creatinine, urea excretion, kidney's weight / body weight ratio, and kidney perfusion pressure in all rat groups at different times of diabetes (2, 4, 6, and 10 weeks). Kidney weight of diabetic rats significantly increased vs. control, control + bis-1,4-DHP, and diabetic + bis-1,4-DHP rats at different times of diabetes. The ratios % kidney weight / 100 g body weight were different between control, control + bis-1,4-DHP, and diabetic + bis-1,4-DHP rats vs. diabetic rats (P < 0.05). Kidney perfusion pressure was decreased by diabetes, while it was partially recovered by bis-1,4-DHP treatment in response to phenylephrine. Bis-1,4-DHP had a tendency to decrease hyperglycemia vs. diabetic rats, even though glycemia was too high as compared with controls, and it ameliorated albuminuria, creatinine, and urea excretion, suggesting a favorable effect on renal haemodynamics. Bis-1,4-DHP, by inhibiting Ca(2+) entrance, induced vasodilation in renal vascular bed and thus may have a nephroprotective effect against diabetes-induced renal dysfunction, but does not have significant impact on hyperglycemia.

  19. Dynamics of the Plasma Membrane Proton Pump.

    PubMed

    Guerra, Federico; Bondar, Ana-Nicoleta

    2015-06-01

    Proton transfer over distances longer than that of a hydrogen bond often requires water molecules and protein motions. Following transfer of the proton from the donor to the acceptor, the change in the charge distribution may alter the dynamics of protein and water. To begin to understand how protonation dynamics couple to protein and water dynamics, here we explore how changes in the protonation state affect water and protein dynamics in the AHA2 proton pump. We find that the protonation state of the proton donor and acceptor groups largely affects the dynamics of internal waters and of specific hydrogen bonds, and the orientation of transmembrane helical segments that couple remote regions of the protein. The primary proton donor/acceptor group D684, can interact with water molecules from the cytoplasmic bulk and/or other protein groups.

  20. Determining the mechanism of cusp proton aurora.

    PubMed

    Xiao, Fuliang; Zong, Qiugang; Su, Zhenpeng; Yang, Chang; He, Zhaoguo; Wang, Yongfu; Gao, Zhonglei

    2013-01-01

    Earth's cusp proton aurora occurs near the prenoon and is primarily produced by the precipitation of solar energetic (2-10 keV) protons. Cusp auroral precipitation provides a direct source of energy for the high-latitude dayside upper atmosphere, contributing to chemical composition change and global climate variability. Previous studies have indicated that magnetic reconnection allows solar energetic protons to cross the magnetopause and enter the cusp region, producing cusp auroral precipitation. However, energetic protons are easily trapped in the cusp region due to a minimum magnetic field existing there. Hence, the mechanism of cusp proton aurora has remained a significant challenge for tens of years. Based on the satellite data and calculations of diffusion equation, we demonstrate that EMIC waves can yield the trapped proton scattering that causes cusp proton aurora. This moves forward a step toward identifying the generation mechanism of cusp proton aurora.

  1. Determining the mechanism of cusp proton aurora

    PubMed Central

    Xiao, Fuliang; Zong, Qiugang; Su, Zhenpeng; Yang, Chang; He, Zhaoguo; Wang, Yongfu; Gao, Zhonglei

    2013-01-01

    Earth's cusp proton aurora occurs near the prenoon and is primarily produced by the precipitation of solar energetic (2–10 keV) protons. Cusp auroral precipitation provides a direct source of energy for the high-latitude dayside upper atmosphere, contributing to chemical composition change and global climate variability. Previous studies have indicated that magnetic reconnection allows solar energetic protons to cross the magnetopause and enter the cusp region, producing cusp auroral precipitation. However, energetic protons are easily trapped in the cusp region due to a minimum magnetic field existing there. Hence, the mechanism of cusp proton aurora has remained a significant challenge for tens of years. Based on the satellite data and calculations of diffusion equation, we demonstrate that EMIC waves can yield the trapped proton scattering that causes cusp proton aurora. This moves forward a step toward identifying the generation mechanism of cusp proton aurora. PMID:23575366

  2. Biodegradation of 1,4-dioxane: effects of enzyme inducers and trichloroethylene.

    PubMed

    Hand, Steven; Wang, Baixin; Chu, Kung-Hui

    2015-07-01

    1,4-Dioxane is a groundwater contaminant and probable human carcinogen. In this study, two well-studied degradative bacteria Mycobacterium vaccae JOB5 and Rhodococcus jostii RHA1 were examined for their 1,4-dioxane degradation ability in the presence and absence of its co-contaminant, trichloroethylene (TCE), under different oxygenase-expression conditions. These two strains were precultured with R2A broth (complex nutrient medium) before supplementation with propane or 1-butanol to induce the expression of different oxygenases. Both propane- and 1-butanol-induced JOB5 and RHA1 were able to degrade 1,4-dioxane, TCE, and mixtures of 1,4-dioxane/TCE. Complete degradation of 1,4-dioxane/TCE mixture was observed only in propane-induced strain JOB5. Inhibition was observed between 1,4-dioxane and TCE for all cells. Furthermore, product toxicity caused incomplete degradation of 1,4-dioxane by 1-butanol-induced JOB5. In general, the more TCE degraded, the greater extent of product toxicity cells experienced; however, susceptibility to product toxicity was found to be both strain- and inducer-dependent. The findings of this study provide fundamental basis for developing an effective in-situ remediation method for 1,4-dioxane-contaminated ground water and the first known study of 1,4-dioxane degradation by wild-type strain RHA1.

  3. Spectral variability in the X-ray pulsar GX 1+4

    NASA Technical Reports Server (NTRS)

    Becker, R. H.; Boldt, E. A.; Holt, S. S.; Pravdo, S. H.; Rothschild, R. E.; Serlemitsos, P. J.; Swank, J. H.

    1976-01-01

    Observations of the galactic center region, hard X-ray source GX 1+4 by the GSFC X-ray spectroscopy experiment on OSO-8 confirm that GX 1+4 is a slow X-ray pulsar. The amount of absorption by cold matter in the spectrum of GX 1+4 varies significantly within a 24 hour period, behavior typical of many X-ray binary systems. The light curve for the pulsations from GX 1+4 appears to be energy dependent.

  4. Biosynthesis and molecular actions of specialized 1,4-naphthoquinone natural products produced by horticultural plants

    PubMed Central

    Widhalm, Joshua R; Rhodes, David

    2016-01-01

    The 1,4-naphthoquinones (1,4-NQs) are a diverse group of natural products found in every kingdom of life. Plants, including many horticultural species, collectively synthesize hundreds of specialized 1,4-NQs with ecological roles in plant–plant (allelopathy), plant–insect and plant–microbe interactions. Numerous horticultural plants producing 1,4-NQs have also served as sources of traditional medicines for hundreds of years. As a result, horticultural species have been at the forefront of many basic studies conducted to understand the metabolism and function of specialized plant 1,4-NQs. Several 1,4-NQ natural products derived from horticultural plants have also emerged as promising scaffolds for developing new drugs. In this review, the current understanding of the core metabolic pathways leading to plant 1,4-NQs is provided with additional emphasis on downstream natural products originating from horticultural species. An overview on the biochemical mechanisms of action, both from an ecological and pharmacological perspective, of 1,4-NQs derived from horticultural plants is also provided. In addition, future directions for improving basic knowledge about plant 1,4-NQ metabolism are discussed. PMID:27688890

  5. Accelerator Science: Proton vs. Electron

    ScienceCinema

    Lincoln, Don

    2016-10-19

    Particle accelerators are one of the most powerful ways to study the fundamental laws that govern the universe. However, there are many design considerations that go into selecting and building a particular accelerator. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of building an accelerator that collides pairs of protons to one that collides electrons.

  6. Alpha proton x ray spectrometer

    NASA Technical Reports Server (NTRS)

    Rieder, Rudi; Waeke, H.; Economou, T.

    1994-01-01

    Mars Pathfinder will carry an alpha-proton x ray spectrometer (APX) for the determination of the elemental chemical composition of Martian rocks and soils. The instrument will measure the concentration of all major and some minor elements, including C, N, and O at levels above typically 1 percent.

  7. Invariant Spin in the Proton

    SciTech Connect

    Thomas, Anthony W.

    2008-10-13

    We discuss recent theoretical progress in understanding the distribution of spin and orbital angular momentum in the proton. Particular attention is devoted to the effect of QCD evolution and to the distinction between 'chiral' and 'invariant' spin. This is particularly significant with respect to the possible presence of polarized strange quarks.

  8. Accelerator Science: Proton vs. Electron

    SciTech Connect

    Lincoln, Don

    2016-10-11

    Particle accelerators are one of the most powerful ways to study the fundamental laws that govern the universe. However, there are many design considerations that go into selecting and building a particular accelerator. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of building an accelerator that collides pairs of protons to one that collides electrons.

  9. Electron and Proton Auroral Dynamics

    NASA Technical Reports Server (NTRS)

    Mende, S. B.; Frey, H. U.; Gerard, J. C.; Hubert, B.; Fuselier, S.; Spann, J. F., Jr.; Gladstone, R.; Burch, J. L.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    Data from the Wide-band Imaging Camera (WIC) sensitive to far ultraviolet auroras and from the Spectrographic Imager (SI) channel SI12, sensitive to proton precipitation induced Lyman alpha were analyzed during a high altitude orbit segment of the IMAGE spacecraft. This segment began during the expansive phase of a substorm. The aurora changed into a double oval configuration, consisting of a set of discrete pole-ward forms and a separate diffuse auroral oval equatorwards, Although IMF Bz was strongly southward considerable activity could be seen poleward of the discrete auroras in the region that was considered to be the polar cap. The SI12 Doppler shifted Lyman alpha signature of precipitating protons show that the proton aurora is on the equatorward side of the diffuse aurora. In the following several hours the IMF Bz field changed signed. Although the general character of the proton and electron aurora did not change, the dayside aurora moved equatorward when the Bz was negative and more bright aurora was seen in the central polar cap during periods of positive Bz.

  10. Hydrogen bonding in proton-transfer complexes of cytosine with trimesic and pyromellitic acids

    NASA Astrophysics Data System (ADS)

    Thomas, Reji; Kulkarni, G. U.

    2008-02-01

    Protons-transfer complexes (1:1) of cytosine with trimesic and pyromellitic acids have been crystallized and single crystal structures have been solved by X-ray crystallography. Both cocrystals exhibit layered structures, each layer containing a plethora of N-H⋯O and O-H⋯O hydrogen bonds between the proton-transfer duplets. The cytosine-trimesic acid complex exhibits a bilayered structure (2.87 Å) in contrast to the commonly observed layered structure seen in the cytosine-pyromellitic acid complex (3.98 Å). Another layered system, an adduct of pyromellitic acid and 1,4-dihydroxy benzene, has also been studied.

  11. Low-Energy Proton Testing Methodology

    NASA Technical Reports Server (NTRS)

    Pellish, Jonathan A.; Marshall, Paul W.; Heidel, David F.; Schwank, James R.; Shaneyfelt, Marty R.; Xapsos, M.A.; Ladbury, Raymond L.; LaBel, Kenneth A.; Berg, Melanie; Kim, Hak S.; Phan, Anthony; Friendlich, M.R.; Rodbell, Kenneth P.; Hakey, Mark C.; Dodd, Paul E.; Reed, Robert A.; Weller, Robert A.; Mendenhall, Marcus H.; Sierawski, B.D.

    2009-01-01

    Use of low-energy protons and high-energy light ions is becoming necessary to investigate current-generation SEU thresholds. Systematic errors can dominate measurements made with low-energy protons. Range and energy straggling contribute to systematic error. Low-energy proton testing is not a step-and-repeat process. Low-energy protons and high-energy light ions can be used to measure SEU cross section of single sensitive features; important for simulation.

  12. How to resolve the proton radius puzzle?

    NASA Astrophysics Data System (ADS)

    Paz, Gil

    2016-09-01

    In 2010 the first measurement of the proton charge radius from spectroscopy of muonic hydrogen was found to be five standard deviations away from the regular hydrogen value. Six years later, this ``proton radius puzzle'' is still unresolved. One of the most promising avenues to test the muonic hydrogen result is a new muon-proton scattering experiment called MUSE. We describe how effective field theory methods will allow to directly connect muonic hydrogen spectroscopy to muon-proton scattering.

  13. Investigation on Preparation Process of the 2011off the Pacific Coast of Tohoku Earthquake (Mw 9.0) By GPS Data

    NASA Astrophysics Data System (ADS)

    Hattori, K.; Han, P.; Tsuruta, N.

    2014-12-01

    The dense continuous GPS Earth Observation Network of Japan (GEONET) of the Geospatial Information Authority of Japan (GSI) has been in practice since 1994. So far, the GEONET data have been widely used for precisely detecting co- and post-seismic deformations. In this paper, we have investigated the long-term surface motion prior to the 2011 off the Pacific coast of Tohoku earthquake (Mw 9.0). Long-term linear trends of precise daily coordinates of GEONET stations have been analyzed and clear changes of the deformation rate starting from about 1.4 year before the mega event have been detected. These changes of the surface deformation rate suggest those of stress accumulation. The spatial distributions of deformation rate have shown westward directional changes in a large area along the Pacific coast prior to the mega event.

  14. Comparative Analyses of Two Thermophilic Enzymes Exhibiting both β-1,4 Mannosidic and β-1,4 Glucosidic Cleavage Activities from Caldanaerobius polysaccharolyticus▿ †

    PubMed Central

    Han, Yejun; Dodd, Dylan; Hespen, Charles W.; Ohene-Adjei, Samuel; Schroeder, Charles M.; Mackie, Roderick I.; Cann, Isaac K. O.

    2010-01-01

    The hydrolysis of polysaccharides containing mannan requires endo-1,4-β-mannanase and 1,4-β-mannosidase activities. In the current report, the biochemical properties of two endo-β-1,4-mannanases (Man5A and Man5B) from Caldanaerobius polysaccharolyticus were studied. Man5A is composed of an N-terminal signal peptide (SP), a catalytic domain, two carbohydrate-binding modules (CBMs), and three surface layer homology (SLH) repeats, whereas Man5B lacks the SP, CBMs, and SLH repeats. To gain insights into how the two glycoside hydrolase family 5 (GH5) enzymes may aid the bacterium in energy acquisition and also the potential application of the two enzymes in the biofuel industry, two derivatives of Man5A (Man5A-TM1 [TM1 stands for truncational mutant 1], which lacks the SP and SLH repeats, and Man5A-TM2, which lacks the SP, CBMs, and SLH repeats) and the wild-type Man5B were biochemically analyzed. The Man5A derivatives displayed endo-1,4-β-mannanase and endo-1,4-β-glucanase activities and hydrolyzed oligosaccharides with a degree of polymerization (DP) of 4 or higher. Man5B exhibited endo-1,4-β-mannanase activity and little endo-1,4-β-glucanase activity; however, this enzyme also exhibited 1,4-β-mannosidase and cellodextrinase activities. Man5A-TM1, compared to either Man5A-TM2 or Man5B, had higher catalytic activity with soluble and insoluble polysaccharides, indicating that the CBMs enhance catalysis of Man5A. Furthermore, Man5A-TM1 acted synergistically with Man5B in the hydrolysis of β-mannan and carboxymethyl cellulose. The versatility of the two enzymes, therefore, makes them a resource for depolymerization of mannan-containing polysaccharides in the biofuel industry. Furthermore, on the basis of the biochemical and genomic data, a molecular mechanism for utilization of mannan-containing nutrients by C. polysaccharolyticus is proposed. PMID:20562312

  15. A bicarbonate cofactor modulates 1,4-dihydroxy-2-naphthoyl-coenzyme a synthase in menaquinone biosynthesis of Escherichia coli.

    PubMed

    Jiang, Ming; Chen, Minjiao; Guo, Zu-Feng; Guo, Zhihong

    2010-09-24

    1,4-Dihydroxy-2-naphthoyl coenzyme A (DHNA-CoA) synthase is a typical crotonase-fold protein catalyzing an intramolecular Claisen condensation in the menaquinone biosynthetic pathway. We have characterized this enzyme from Escherichia coli and found that it is activated by bicarbonate in a concentration-dependent manner. The bicarbonate binding site has been identified in the crystal structure of a virtually identical ortholog (96.8% sequence identity) from Salmonella typhimurium through comparison with a bicarbonate-insensitive orthologue. Kinetic properties of the enzyme and its site-directed mutants of the bicarbonate binding site indicate that the exogenous bicarbonate anion is essential to the enzyme activity. With this essential catalytic role, the simple bicarbonate anion is an enzyme cofactor, which is usually a small organic molecule derived from vitamins, a metal ion, or a metal-containing polyatomic anionic complex. This finding leads to classification of the DHNA-CoA synthases into two evolutionarily conserved subfamilies: type I enzymes that are bicarbonate-dependent and contain a conserved glycine at the bicarbonate binding site; and type II enzymes that are bicarbonate-independent and contain a conserved aspartate at the position similar to the enzyme-bound bicarbonate. In addition, the unique location of the enzyme-bound bicarbonate allows it to be proposed as a catalytic base responsible for abstraction of the α-proton of the thioester substrate in the enzymatic reaction, suggesting a unified catalytic mechanism for all DHNA-CoA synthases.

  16. Molecular structure of hydrated complex of 1,4-dimethylpiperazine di-betaine with L-tartaric acid

    NASA Astrophysics Data System (ADS)

    Dega-Szafran, Z.; Katrusiak, A.; Szafran, M.

    2008-12-01

    1,4-Dimethylpiperazine di-betaine (DBPZ) forms a crystalline complex with L-tartaric acid (TA) and two and a half water molecules. The crystals are monoclinic, space group P2 1. The piperazine has a chair conformation with the methyl groups in the equatorial positions and the axial CH 2COO substituents. One of the CH 2COO group is protonated and forms with the neighboring DBPZ molecule the COO sbnd H⋯OOC hydrogen bond of the length 2.476(3) Å, which links them into a chain. The semi-tartrate anions, form a chain through the symmetrical, short COO⋯H⋯OOC hydrogen bond of 2.464(3) Å. The crystals have a layer structure, where hydrogen-bonded sheets of TA and water molecules are separated by the chains of DBPZ; no H-bonds between water and DBPZ are present. In the optimized molecules in the B3LYP/6-31G(d,p) approach, the tartaric acid interacts with the tartrate di-anions through the COO sbnd H⋯OOC hydrogen bonds of 2.506 Å, while the DBPZ has the same conformation as in the crystals. The FTIR spectrum of the solid complex is consistent with the X-ray results.

  17. Synthesis, spectral characterization, crystal structure and molecular docking study of 2,7-diaryl-1,4-diazepan-5-ones

    NASA Astrophysics Data System (ADS)

    Sethuvasan, S.; Sugumar, P.; Maheshwaran, V.; Ponnuswamy, M. N.; Ponnuswamy, S.

    2016-07-01

    In this study, a series of variously substituted r-2,c-7-diaryl-1,4-diazepan-5-ones 9-16 have been synthesized using Schmidt rearrangement and are characterized by IR, mass and 1D & 2D NMR spectral data. The proton NMR coupling constant and estimated dihedral angles reveal that the compounds 9-16 prefer a chair conformation with equatorial orientation of alkyl and aryl groups. Single crystal X-ray structure has been solved for compounds 9 and 11 which also indicates the preference for distorted chair conformation with equatorial orientation of substituents. The compounds 9-16 have been docked with the structure of Methicillin-resistant Staphylococcus aureus (MRSA) and the results demonstrate that compound 10 is having better docking score and glide energy than others and it is comparable to co-crystal ligand. Furthermore, all the compounds have been evaluated for their antibacterial and antioxidant activities. All the compounds show moderate antibacterial activity and only 11 exhibits better activity against S. aures and Escherichia coli. The compounds 11, 13 and 14 exhibit half of the antioxidant power when compared to the BHT and the remaining compounds show moderate activity.

  18. The effects of 1,4-cyclohexanediol on frozen ram spermatozoa.

    PubMed

    Quan, G B; Wu, S S; Lan, Z G; Yang, H Y; Shao, Q Y; Hong, Q H

    2013-01-01

    In order to improve the quality of frozen spermatozoa of Yunnan semi-fine wool sheep, 1, 4-cyclohexanediol (1, 4-CHD) as a synthetic ice blocker was used for cryopreservation of ram spermatozoa in this study. Briefly, following collection by electric stimulation, equilibration at 5℃ following dilution with the freezing extender, and pre-freezing in liquid nitrogen vapor, the ram spermatozoa were preserved in liquid nitrogen for one month. In addition, the effects of osmolarity of the diluting extenders used for evaluation of frozen spermatozoa quality were also assessed. The results indicated addition of 1, 4-CHD could not increase the motility of ram spermatozoa after cryopreservation and thawing. With the elevation of the concentrations of 1, 4-CHD, the motility and moving velocity of frozen ram spermatozoa showed a steady decrease. Additionally, the presence of 1, 4-CHD cannot increase the percentage of frozen spermatozoa with intact acrosome and membrane. When the isotonic binding buffer was used to dilute the thawed spermatozoa, the percentage of cells labeled with propidium iodide (PI) after cryopreservation in the presence of 1, 4-CHD was significantly higher than that of spermatozoa frozen in the absence of 1, 4-CHD (P < 0.05). However, the percentage of frozen-thawed spermatozoa with exposed PS in the presence of 1, 4-CHD was significantly less than that of spermatozoa frozen in the absence of 1, 4-CHD (P < 0.01). When the basic extenders with an osmolarity of 404mOsm, 528mOsm, 648mOsm, or 853mOsm were used to dilute the frozen-thawed spermatozoa respectively, there is no significant difference between the four groups with respect to the moving velocity and membrane integrity (P > 0.05). In conclusion, the presence of 1, 4-CHD cannot improve the motility, moving velocity, acrosome staus, and membrane integrity of frozen ram spermatozoa. However, 1, 4-CHD may inhibit apoptosis caused by freezing and thawing.

  19. High performance cobalt-free Cu1.4Mn1.6O4 spinel oxide as an intermediate temperature solid oxide fuel cell cathode

    NASA Astrophysics Data System (ADS)

    Zhen, Shuying; Sun, Wang; Li, Peiqian; Tang, Guangze; Rooney, David; Sun, Kening; Ma, Xinxin

    2016-05-01

    In this work Cu1.4Mn1.6O4 (CMO) spinel oxide is prepared and evaluated as a novel cobalt-free cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). Single phase CMO powder with cubic structure is identified using XRD. XPS results confirm that mixed Cu+/Cu2+ and Mn3+/Mn4+ couples exist in the CMO sample, and a maximum conductivity of 78 S cm-1 is achieved at 800 °C. Meanwhile, CMO oxide shows good thermal and chemical compatibility with a 10 mol% Sc2O3 stabilized ZrO2 (ScSZ) electrolyte material. Impedance spectroscopy measurements reveals that CMO exhibits a low polarization resistance of 0.143 Ω cm2 at 800 °C. Furthermore, a Ni-ScSZ/ScSZ/CMO single cell demonstrates a maximum power density of 1076 mW cm-2 at 800 °C under H2 (3% H2O) as the fuel and ambient air as the oxidant. These results indicate that Cu1.4Mn1.6O4 is a superior and promising cathode material for IT-SOFCs.

  20. JPRS Report Science & Technology China: Energy 5MW Low Power Reactor

    DTIC Science & Technology

    2007-11-02

    monocrystalline silicon neutron irradiation doping, molybdenum- technetium isotope production, irradia- tion coloring of gemstones, and so on. Key terms: 5MW low...power reactor, unloaded fuel ele- ments, element damage monitoring, irradiation, monoc- rystalline silicon, molybdenum- technetium isotopes. I...comprehensive use of the LPR, and undertake monocrystalline silicon neutron irradiation doping, molybdenum- technetium isotope production, irradiation color

  1. Continuous-wave 193.4 nm laser with 120 mW output power.

    PubMed

    Sakuma, Jun; Kaneda, Yushi; Oka, Naoya; Ishida, Takayuki; Moriizumi, Koichi; Kusunose, Haruhiko; Furukawa, Yasunori

    2015-12-01

    This Letter describes an all-solid-state continuous-wave, deep-ultraviolet coherent source that generates more than 100 mW of output power at 193.4 nm. The source is based on nonlinear frequency conversion of three single-frequency infrared fiber laser master-oscillator power-amplifier (MOPA) light sources.

  2. Effect of MW-assisted roasting on nutritional and chemical properties of hazelnuts

    PubMed Central

    Kalkan, Fatih; Kranthi Vanga, Sai; Gariepy, Yvan; Raghavan, Vijaya

    2015-01-01

    In order to enhance the flavor, texture, color, and appearance of hazelnuts, they are roasted during postharvest processing. In this study, raw hazelnuts (Corylus avellana L.) were roasted using microwave (MW) and MW-assisted hot air methods under various roasting conditions. The hazelnuts roasted were then examined to determine the percent DPPH radical scavenging activity, antioxidant capacity, total phenolic content, resistant starch, non-resistant starch, total starch, and protein concentration. The roasting experiments were done using a completely randomized factorial arrangement of two roasting types by three roasting times (9, 15, and 21 min) by three roasting temperatures (70, 90, and 110°C) using three replications within each experiment. These roasting methods were found to yield significant differences in antioxidant capacity, total phenolic content, resistant starch, non-resistant starch, and protein concentration between MW and MW-assisted hot air roasting processes, while no difference was found in percent DPPH radical scavenging activity and total starch. The results obtained may be of great importance to the food research community and industrial hazelnut roasting technologies. PMID:26689314

  3. The Upgrade of the DIII-D GHz ECH System to 6 MW

    SciTech Connect

    Cary, W.P.; Callis, R.W.; Lohr, J.M.; Ponce, D.; Legg, R.A.

    1999-11-01

    ECH power has proven capabilities to both heat and drive current in energetic plasmas. Recent developments in high power sources have made the use of these capabilities in energetic plasmas feasible. For the second phase of ECH power on DIII-D, there will be three 1 MW sources added to the existing 3 MW for a total generated power of 6 MW. The upgrade is based on the use of single disc CVD (chemical vapor deposition) diamond windows on 1 MW gyrotrons developed by CPI. AU gyrotrons are connected to the tokamak by low-loss-windowless evacuated transmission lines using circular corrugated waveguide for propagation in the HE{sub 11} mode. Each waveguide system incorporates a two-mirror launcher which can steer the rf beam poloidally from the center to the outer edge of the plasma and toroidally for either co- or counter-current drive. The total system overview and integration with existing systems will be discussed along with the new aspects of the upgrade from building modifications to the new launchers. Much of the upgrade is comprised of existing designs, which will need only slight modifications, while some components have required new designs because of longer pulse lengths.

  4. Model Validation at the 204 MW New Mexico Wind Energy Center: Preprint

    SciTech Connect

    Muljadi, E.; Butterfield, C. P.; Ellis, A.; Mechenbier, J.; Hochheimer, J.; Young, R.; Miller, N.; Delmerico, R.; Zavadil, R.; Smith, J. C.

    2006-06-01

    In this paper, we describe methods to derive and validate equivalent models for a large wind farm. FPL Energy's 204-MW New Mexico Wind Energy Center, which is interconnected to the Public Service Company of New Mexico (PNM) transmission system, was used as a case study. The methods described are applicable to any large wind power plant.

  5. Effect of MW-assisted roasting on nutritional and chemical properties of hazelnuts.

    PubMed

    Kalkan, Fatih; Vanga, Sai Kranthi; Gariepy, Yvan; Raghavan, Vijaya

    2015-01-01

    In order to enhance the flavor, texture, color, and appearance of hazelnuts, they are roasted during postharvest processing. In this study, raw hazelnuts (Corylus avellana L.) were roasted using microwave (MW) and MW-assisted hot air methods under various roasting conditions. The hazelnuts roasted were then examined to determine the percent DPPH radical scavenging activity, antioxidant capacity, total phenolic content, resistant starch, non-resistant starch, total starch, and protein concentration. The roasting experiments were done using a completely randomized factorial arrangement of two roasting types by three roasting times (9, 15, and 21 min) by three roasting temperatures (70, 90, and 110°C) using three replications within each experiment. These roasting methods were found to yield significant differences in antioxidant capacity, total phenolic content, resistant starch, non-resistant starch, and protein concentration between MW and MW-assisted hot air roasting processes, while no difference was found in percent DPPH radical scavenging activity and total starch. The results obtained may be of great importance to the food research community and industrial hazelnut roasting technologies.

  6. Steady-state operation of 170 GHz 1 MW gyrotron for ITER

    NASA Astrophysics Data System (ADS)

    Kasugai, A.; Sakamoto, K.; Takahashi, K.; Kajiwara, K.; Kobayashi, N.

    2008-05-01

    A 170 GHz gyrotron has been developed at JAEA, which has achieved operation of 1 MW/800 s and up to 55% efficiency. This is the first demonstration of a gyrotron achieving and even exceeding the ITER operating requirements of 1 MW/500 s and 50% efficiency. In addition the gyrotron demonstrated operation for 1 h with an output power of 0.6 MW. The oscillation was stable with all cooling water temperatures and vacuum pressure reaching equilibrium conditions during the pulse length at either power level. The successful operation was aided by a very low level of stray radiation (~2% of the output power), which contributed to fast conditioning and stable operation. The output power from the gyrotron was coupled into an ITER sized corrugated waveguide (phi = 63.5 mm) via a matching optics unit with a total of 0.97 MW transmitted to the dummy load after two miter bends and ~7 m of a waveguide without any trouble. These results give an encouraging outlook for the success of the ITER electron cyclotron heating and current drive system.

  7. 5 mW parallel-connected resonant-tunnelling diode oscillator

    NASA Technical Reports Server (NTRS)

    Stephan, K. D.; Wong, S.-C.; Brown, E. R.; Molvar, K. M.; Calawa, A. R.; Manfra, M. J.

    1992-01-01

    A new type of resonant-tunneling diode (RTD) oscillator that generates 5 mW at 1.18 GHz is reported. This result was obtained by connecting in parallel 25 individual diodes designed for such a connection. This experiment demonstrates that RTDs can successfully be used in a chip-level power-combining circuit.

  8. Vibrational Relaxation of the Aqueous Proton in Acetonitrile: Ultrafast Cluster Cooling and Vibrational Predissociation.

    PubMed

    Ottosson, N; Liu, L; Bakker, H J

    2016-07-28

    We study the ultrafast O-H stretch vibrational relaxation dynamics of protonated water clusters embedded in a matrix of deuterated acetonitrile, using polarization-resolved mid-IR femtosecond spectroscopy. The clusters are produced by mixing triflic (trifluoromethanesulfonic) acid and H2O in molar ratios of 1:1, 1:2, and 1:3, thus varying the degree of hydration of the proton. At all hydration levels the excited O-H stretch vibration of the hydrated proton shows an ultrafast vibrational relaxation with a time constant T1 < 100 fs, leading to an ultrafast local heating of the protonated water cluster. This excess thermal energy, initially highly localized to the region of the excited proton, first re-distributes over the aqueous cluster and then dissipates into the surrounding acetonitrile matrix. For clusters with a triflic acid to H2O ratio of 1:3 these processes occur with time constants of 320 ± 20 fs and 1.4 ± 0.1 ps, respectively. The cooling of the clusters reveals a long-living, underlying transient absorption change with high anisotropy. We argue that this feature stems from the vibrational predissociation of a small fraction of the proton hydration structures, directly following the ultrafast infrared excitation.

  9. Laboratory Investigation Of Mechanisms For 1,4-Dioxane Destruction By Ozone In Water

    EPA Science Inventory

    Advances in analytical detection methods have made it possible to quantify 1,4-dioxane contamination in groundwater, even at well-characterized sites where it had not been previously detected. Although 1,4-dioxane is difficult to treat because of its chemical and physical proper...

  10. 20 CFR 1.4 - Where are other rules concerning OWCP functions found?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... functions found? 1.4 Section 1.4 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF... functions found? (a) The rules of the OWCP governing its functions under the Longshore and Harbor Workers' Compensation Act and its extensions are set forth in subchapter A of chapter VI of this title. (b) The rules...

  11. IN-SITU OXIDATION OF 1,4-DIOXANE (LABORATORY RESULTS)

    EPA Science Inventory

    Interest in the solvent stabilizer, 1,4-dioxane, is increasing because analytical detection limits have decreased indicating its presence at chlorinated volatile organic compound contaminated sites. The most common method for removing 1,4-dioxane from contaminated water is advanc...

  12. Anti-voltage-gated potassium channel Kv1.4 antibodies in myasthenia gravis.

    PubMed

    Romi, Fredrik; Suzuki, Shigeaki; Suzuki, Norihiro; Petzold, Axel; Plant, Gordon T; Gilhus, Nils Erik

    2012-07-01

    Myasthenia gravis (MG) is an autoimmune disease characterized by skeletal muscle weakness mainly caused by acetylcholine receptor antibodies. MG can be divided into generalized and ocular, and into early-onset (<50 years of age) and late-onset (≥50 years of age). Anti-Kv1.4 antibodies targeting α-subunits (Kv1.4) of the voltage-gated potassium K(+) channel occurs frequently among patients with severe MG, accounting for 18% of a Japanese MG population. The aim of this study was to characterize the clinical features and serological associations of anti-Kv1.4 antibodies in a Caucasian MG population with mild and localized MG. Serum samples from 129 Caucasian MG patients with mainly ocular symptoms were tested for the presence of anti-Kv1.4 antibodies and compared to clinical and serological parameters. There were 22 (17%) anti-Kv1.4 antibody-positive patients, most of them women with late-onset MG, and all of them with mild MG. This contrasts to the Japanese anti-Kv1.4 antibody-positive patients who suffered from severe MG with bulbar symptoms, myasthenic crisis, thymoma, myocarditis and prolonged QT time on electrocardiography, despite equal anti-Kv1.4 antibody occurrence in both populations. No other clinical or serological parameters influenced anti-Kv1.4 antibody occurrence.

  13. IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR 1,4 - DIOXANE

    EPA Science Inventory

    1,4 -Dioxane is a cyclic ether that is primarily utilized for industrial applications. These applications include 1,4 -dioxane as a solvent, reaction medium, wetting, degreasing, and dispersing agent, and for stabilization of chlorinated solvents (e.g. 1,1,1 -trichloroethane). ...

  14. 26 CFR 1.4-4 - Short taxable year caused by death.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 1 2013-04-01 2013-04-01 false Short taxable year caused by death. 1.4-4... TAXES Normal Taxes and Surtaxes § 1.4-4 Short taxable year caused by death. An individual making a... taxable year results from the death of the taxpayer. Tax on Corporations...

  15. 26 CFR 1.4-4 - Short taxable year caused by death.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 1 2011-04-01 2009-04-01 true Short taxable year caused by death. 1.4-4 Section... Normal Taxes and Surtaxes § 1.4-4 Short taxable year caused by death. An individual making a return for a... results from the death of the taxpayer. Tax on Corporations...

  16. 26 CFR 1.4-4 - Short taxable year caused by death.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Short taxable year caused by death. 1.4-4 Section... Normal Taxes and Surtaxes § 1.4-4 Short taxable year caused by death. An individual making a return for a... results from the death of the taxpayer. Tax on Corporations...

  17. Laboratory Investigations Of Mechanisms For 1,4-Dioxane Destruction By Ozone In Water (Presentation)

    EPA Science Inventory

    Advances in analytical detection methods have made it possible to quantify 1,4-dioxane contamination in groundwater, even a well-characterized sites where it had not been previously detected. Although 1,4-dioxane is difficult to treat because of its chemical and physical propert...

  18. 40 CFR 721.10662 - Acetaldehyde, substituted-, reaction products with 2-butyne-1, 4-diol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acetaldehyde, substituted-, reaction...-, reaction products with 2-butyne-1, 4-diol (generic). (a) Chemical substance and significant new uses...-, reaction products with 2-butyne-1, 4-diol (PMN P-11-204) is subject to reporting under this section for...

  19. 40 CFR 180.1142 - 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance. 180.1142 Section 180.1142 Protection of Environment ENVIRONMENTAL... FOOD Exemptions From Tolerances § 180.1142 1,4-Dimethylnaphthalene; exemption from the requirement of...

  20. 40 CFR 180.1142 - 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance. 180.1142 Section 180.1142 Protection of Environment ENVIRONMENTAL... FOOD Exemptions From Tolerances § 180.1142 1,4-Dimethylnaphthalene; exemption from the requirement of...

  1. 40 CFR 180.1142 - 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance. 180.1142 Section 180.1142 Protection of Environment ENVIRONMENTAL... FOOD Exemptions From Tolerances § 180.1142 1,4-Dimethylnaphthalene; exemption from the requirement of...

  2. 40 CFR 180.1142 - 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance. 180.1142 Section 180.1142 Protection of Environment ENVIRONMENTAL... FOOD Exemptions From Tolerances § 180.1142 1,4-Dimethylnaphthalene; exemption from the requirement of...

  3. 40 CFR 180.1142 - 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false 1,4-Dimethylnaphthalene; exemption from the requirement of a tolerance. 180.1142 Section 180.1142 Protection of Environment ENVIRONMENTAL... FOOD Exemptions From Tolerances § 180.1142 1,4-Dimethylnaphthalene; exemption from the requirement of...

  4. 21 CFR 177.1315 - Ethylene-1, 4-cyclohexylene dimethylene terephthalate copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... glycol and 1 to 34 mole percent of 1,4-cyclo-hexanedimethanol (70 percent trans isomer, 30 percent cls isomer) Inherent viscosity of a 0.50 percent solution of the copolymer in phenol-tetrachloroethane (60:40... ethylene glycol and 1 to 15 mole percent of 1,4-cyclohexane-di-methanol (70 percent trans isomer,...

  5. 21 CFR 177.1315 - Ethylene-1, 4-cyclohexylene dimethylene terephthalate copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... glycol and 1 to 34 mole percent of 1,4-cyclo-hexanedimethanol (70 percent trans isomer, 30 percent cls isomer) Inherent viscosity of a 0.50 percent solution of the copolymer in phenol-tetrachloroethane (60:40... ethylene glycol and 1 to 15 mole percent of 1,4-cyclohexane-di-methanol (70 percent trans isomer,...

  6. 21 CFR 177.1315 - Ethylene-1, 4-cyclohexylene dimethylene terephthalate copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... glycol and 1 to 34 mole percent of 1,4-cyclo-hexanedimethanol (70 percent trans isomer, 30 percent cls isomer) Inherent viscosity of a 0.50 percent solution of the copolymer in phenol-tetrachloroethane (60:40... ethylene glycol and 1 to 15 mole percent of 1,4-cyclohexane-di-methanol (70 percent trans isomer,...

  7. 21 CFR 177.1315 - Ethylene-1, 4-cyclohexylene dimethylene terephthalate copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... glycol and 1 to 34 mole percent of 1,4-cyclo-hexanedimethanol (70 percent trans isomer, 30 percent cls isomer) Inherent viscosity of a 0.50 percent solution of the copolymer in phenol-tetrachloroethane (60:40... ethylene glycol and 1 to 15 mole percent of 1,4-cyclohexane-di-methanol (70 percent trans isomer,...

  8. 26 CFR 1.4-4 - Short taxable year caused by death.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 1 2014-04-01 2013-04-01 true Short taxable year caused by death. 1.4-4 Section... Normal Taxes and Surtaxes § 1.4-4 Short taxable year caused by death. An individual making a return for a... results from the death of the taxpayer. Tax on Corporations...

  9. 26 CFR 1.4-4 - Short taxable year caused by death.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 1 2012-04-01 2012-04-01 false Short taxable year caused by death. 1.4-4... TAXES Normal Taxes and Surtaxes § 1.4-4 Short taxable year caused by death. An individual making a... taxable year results from the death of the taxpayer. Tax on Corporations...

  10. 17 CFR 240.15Ba1-4 - Withdrawal from municipal advisor registration.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Withdrawal from municipal advisor registration. 240.15Ba1-4 Section 240.15Ba1-4 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL RULES AND REGULATIONS, SECURITIES EXCHANGE ACT OF 1934 Rules...

  11. Bioactive 1 4-Dihydroxy-5-phenyl-2-pyridinone alkaloids from Septoria pistaciarum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four new 1,4-dihydroxy-5-phenyl-2-pyridinone alkaloids (1-4) were isolated from an EtOAc extract of a culture medium of Septoria pistaciarum. The structures of these compounds were determined by spectroscopic methods, and the absolute configuration of the major compound 1 by X-ray crystallographic a...

  12. Dephosphorylation of 1D-myo-inositol 1,4-bisphosphate in rat liver.

    PubMed Central

    Morris, A J; Storey, D J; Downes, C P; Michell, R H

    1988-01-01

    Dephosphorylation of 1D-myo-inositol 1,4-bisphosphate [Ins(1,4)P2] in rat liver is catalysed by a cytosolic phosphatase that removes the 1-phosphate group. The Km for Ins(1,4)P2 is approx. 17 microM. Li+ (100 mM) causes 50% inhibition of Ins(1,4)P2 phosphatase activity when activity is measured at the very low substrate concentration of 10 nM, but on raising the substrate concentration to 100 microM there is a greater than 10-fold increase in sensitivity to Li+, suggesting that Li+ acts mainly, but not entirely, as an uncompetitive inhibitor of Ins(1,4)P2 phosphatase. In addition, rat liver cytosol shows Li+-sensitive phosphatase activity against 1D-myo-inositol 1-,3- and 4-monophosphates. The Ins(1,4)P2 1-phosphatase and inositol monophosphatase activities all share an apparent Mr of 47 x 10(3), as determined by gel-filtration chromatography. However, the Ins(1,4)P2 1-phosphatase is more sensitive to inactivation by heat, and can be separated from inositol monophosphatase activity by anion-exchange chromatography. We conclude that rat liver cytosol contains an Ins(1,4)P2 1-phosphatase that is distinct from, but in many ways similar to, inositol monophosphatase. PMID:2848493

  13. Calculation of Top Squark Production in Proton-Proton Collisions

    SciTech Connect

    Linville, Andrea J.; /Washington U., St. Louis /SLAC

    2010-08-25

    Though the Standard Model of particle physics is an elegant theory which has been studied extensively for decades, it leaves many fundamental questions unanswered and is thus widely believed to be incomplete. Possible extensions to the Standard Model (SM) have been postulated and are in the process of being investigated experimentally. The most promising extension is the Minimal Supersymmetric Model (MSSM) which relates every SM particle to a superpartner that differs by 1/2 unit of spin. The lightest supersymmetric quark, or squark, is expected to be the stop, and the search for this particle is an important experimental task. In this analysis, we use parton-model methods to predict the stop production cross section in proton-proton collisions at LHC energies.

  14. Threshold pion production from proton-proton collisions

    SciTech Connect

    Lee, T.S.H.

    1995-08-01

    We showed that the threshold production of {pi}{sup 0}pp, {pi}{sup +}np, and {pi}{sup +}d from proton-proton collisions can be consistently described by a model consisting of pion s-wave rescattering and N{bar N} pair-terms of heavy-meson exchanges. The large difference between {sigma}{sup tot}(pp {yields} {pi}{sup +}d) and {sigma}{sup tot}(pp {yields} {pi}{sup +}np) is understood from the orthogonality of the deuteron and the np scattering wave functions. In a calculation using the Paris potential, we find that the data can be reproduced best by using a soft {pi}NN form factor with {Delta} = 650 MeV for a monopole form. This is consistent with our earlier studies of pion production in the A-excitation region. A paper describing this result was submitted for publication.

  15. Mn1.4Co1.4Cu0.2O4 spinel protective coating on ferritic stainless steels for solid oxide fuel cell interconnect applications

    NASA Astrophysics Data System (ADS)

    Chen, Guoyi; Xin, Xianshuang; Luo, Ting; Liu, Leimin; Zhou, Yuchun; Yuan, Chun; Lin, Chucheng; Zhan, Zhongliang; Wang, Shaorong

    2015-03-01

    In an attempt to reduce the oxidation and Cr evaporation rates of solid oxide fuel cells (SOFCs), Mn1.4Co1.4Cu0.2O4 spinel coating is developed on the Crofer22 APU ferritic stainless steel substrate by a powder reduction technique. Doping of Cu into Mn-Co spinels improves electrical conductivity as well as thermal expansion match with the Crofer22 APU interconnect. Good adhesion between the coating and the alloy substrate is achieved by the reactive sintering process using the reduced powders. Long-term isothermal oxidation experiment and area specific resistance (ASR) measurement are investigated. The ASR is less than 4 mΩ cm2 even though the coated alloy undergoes oxidation at 800 °C for 530 h and four thermal cycles from 800 °C to room temperature. The Mn1.4Co1.4Cu0.2O4 spinel coatings demonstrate excellent anti-oxidation performance and long-term stability. It exhibits a promising prospect for the practical application of SOFC alloy interconnect.

  16. Solid-phase organic synthesis of 2-tridecanyl-1,4-naphthoquinone and 2-tridecanyl-1,4-naphthodiol that form redox-active micelles and vesicles.

    PubMed

    Bugarin, Alejandro; Martinez, Luis E; Cooke, Peter; Islam, Tadiqul; Noveron, Juan C

    2014-10-01

    The solid-phase synthesis of new amphiphilic compounds is reported. It is based on a newly designed 1,4-naphthoquinone derivative that contains polar and nonpolar groups and self-assembles into micelles or vesicles in water depending on the concentration. They also display redox-active properties.

  17. Proven clean coal technology at work: The Provence 250 MW CFB boiler

    SciTech Connect

    Lucat, P.; Jacquet, L.; Roulet, V.

    1997-12-31

    The successful start-up, in the last months of 1995, of the 250 MW Provence/Gardanne unit represents a significant milestone in the development of atmospheric Circulating Fluidized Bed (CFB) boilers for power stations. This high performance unit (over 700 tonnes/hour of steam at 169 bar, 567 C, with reheat at 566 C) has been in operation since April 1996. It is the first CFB boiler in the world to reach such a capacity. CFB boilers, with their excellent SO{sub 2} and NOx emission control capability, are today recognized as a very attractive Clean Coal Technology, particularly because of their simplicity. The Provence/Gardanne project is part of a French development program for large CFB boilers which has been elaborated in the perspective of domestic applications (mainly future semi-base load units) and of the overseas market. It responds to the converging interests of Electricite de France (EDF), Charbonnages de France (CdF)and GEC ALSTHOM Stein Industrie. Besides comprehensive R and D-type investigations aiming at an in-depth understanding of the CFB process and preparing for future scale-up and development, this program has already been marked by two outstanding commercial repowering projects: a 125 MW unit, in operation since 1990 at the Emile Huchet Power Station, and the 250 MW Provence unit. These boilers have been designed and supplied by GEC ALSTHOM Stein Industrie in the framework of their long standing cooperation with Lurgi, a pioneer of the CFB process. The main components are: (1) Furnace; (2) Cyclone; (3) Back-pass; (4) Ash cooler; (5) External Heat Exchanger. However, a brief discussion of some key design options affecting bed performance is necessary to better understand this technology. The paper describes the design of the system, the retrofitting project at Emile Huchet/Carling, and then gives background information on the Provence/Gardanne retrofit, describing SO{sub 2} emissions, the 250 MW boiler, and results from the performance tests. The

  18. Biochemical characterization of a GH53 endo-β-1,4-galactanase and a GH35 exo-β-1,4-galactanase from Penicillium chrysogenum.

    PubMed

    Sakamoto, Tatsuji; Nishimura, Yuichi; Makino, Yosuke; Sunagawa, Yoichi; Harada, Naoki

    2013-04-01

    An endo-β-1,4-galactanase (PcGAL1) and an exo-β-1,4-galactanase (PcGALX35C) were purified from the culture filtrate of Penicillium chrysogenum 31B. Pcgal1 and Pcgalx35C cDNAs encoding PcGAL1 and PcGALX35C were isolated by in vitro cloning. The deduced amino acid sequences of PcGAL1 and PcGALX35C are highly similar to a putative endo-β-1,4-galactanase of Aspergillus terreus (70% amino acid identity) and a putative β-galactosidase of Neosartorya fischeri (72%), respectively. Pfam analysis revealed a "Glyco_hydro_53" domain in PcGAL1. PcGALX35C is composed of five distinct domains including "Glyco_hydro_35," "BetaGal_dom2," "BetaGal_dom3," and two "BetaGal_dom4_5" domains. Recombinant enzymes (rPcGAL1 and rPcGALX35C) expressed in Escherichia coli and Pichia pastoris, respectively, were active against lupin galactan. The reaction products of lupin galactan revealed that rPcGAL1 cleaved the substrate in an endo manner. The enzyme accumulated galactose and galactobiose as the main products. The smallest substrate for rPcGAL1 was β-1,4-galactotriose. On the other hand, rPcGALX35C released only galactose from lupin galactan throughout the reaction, indicating that it is an exo-β-1,4-galactanase. rPcGALX35C was active on both β-1,4-galactobiose and triose, but not on lactose, β-1,3- or β-1,6-galactooligosaccharides even after 24 h of incubation. To our knowledge, this is the first report of a gene encoding a microbial exo-β-1,4-galactanase. rPcGAL1 and rPcGALX35C acted synergistically in the degradation of lupin galactan and soybean arabinogalactan. Lupin galactan was almost completely degraded to galactose by the combined actions of rPcGAL1 and rPcGALX35C. Surprisingly, neither rPcGAL1 nor rPcGALX35C released any galactose from sugar beet pectin.

  19. Coulomb Stress Change and Seismic Hazard of Rift Zones in Southern Tibet after the 2015 Mw7.8 Nepal Earthquake and Its Mw7.3 Aftershock

    NASA Astrophysics Data System (ADS)

    Dai, Z.; Zha, X.; Lu, Z.

    2015-12-01

    In southern Tibet (30~34N, 80~95E), many north-trending rifts, such as Yadong-Gulu and Lunggar rifts, are characterized by internally drained graben or half-graben basins bounded by active normal faults. Some developed rifts have become a portion of important transportation lines in Tibet, China. Since 1976, eighty-seven >Mw5.0 earthquakes have happened in the rift regions, and fifty-five events have normal faulting focal mechanisms according to the GCMT catalog. These rifts and normal faults are associated with both the EW-trending extension of the southern Tibet and the convergence between Indian and Tibet. The 2015 Mw7.8 Nepal great earthquake and its Mw7.3 aftershock occurred at the main Himalayan Thrust zone and caused tremendous damages in Kathmandu region. Those earthquakes will lead to significant viscoelastic deformation and stress changes in the southern Tibet in the future. To evaluate the seismic hazard in the active rift regions in southern Tibet, we modeled the slip distribution of the 2015 Nepal great earthquakes using the InSAR displacement field from the ALOS-2 satellite SAR data, and calculated the Coulomb failure stress (CFS) on these active normal faults in the rift zones. Because the estimated CFS depends on the geometrical parameters of receiver faults, it is necessary to get the accurate fault parameters in the rift zones. Some historical earthquakes have been studied using the field data, teleseismic data and InSAR observations, but results are in not agreement with each other. In this study, we revaluated the geometrical parameters of seismogenic faults occurred in the rift zones using some high-quality coseismic InSAR observations and teleseismic body-wave data. Finally, we will evaluate the seismic hazard in the rift zones according to the value of the estimated CFS and aftershock distribution.

  20. Recent development in [1,4]benzodiazepines as potent anticancer agents: a review.

    PubMed

    Gill, Rupinder Kaur; Kaushik, Shiv Om; Chugh, Jasreen; Bansal, Sumit; Shah, Anamik; Bariwal, Jitender

    2014-01-01

    The [1,4]benzodiazepine is an important class of heterocyclic compounds and clinically used for many ailments in humans. The [1,4]benzodiazepine has unique structure that mimics the peptide linkage. This interesting observation completely shifted the interest of medicinal chemist for [1,4]benzodiazepine from CNS acting drugs to anticancer agents. During last few decades, a large number of reports have appeared in the literature highlighting the anticancer activity of [1,4]benzodiazepines. Here, in this article, we have discussed the brief synthesis, origin of [1,4]benzodiazepines as anticancer agent, their mechanism of action and latest developments in this field. We have compiled the most important literature reports from last few decades till date.

  1. Proton hydrates as soft ion/ion proton transfer reagents for multiply deprotonated biomolecules

    NASA Astrophysics Data System (ADS)

    Bowers, Jeremiah J.; Hodges, Brittany D. M.; Saad, Ola M.; Leary, Julie A.; McLuckey, Scott A.

    2008-10-01

    Ion/ion proton transfer from protonated strong gaseous bases such as pyridine and 1,8-bis(dimethylamino)naphthalene (i.e., the proton sponge), to multiply charged anions derived from a sulfated pentasaccharide drug, Arixtra(TM), gives rise to extensive fragmentation of the oligosaccharide. This drug serves as a model for sulfated glycosaminoglycans, an important class of polymers in glycobiology. The extent of fragmentation appears to correlate with the proton affinity of the molecule used to transfer the proton, which in turn correlates with the reaction exothermicity. Consistent with tandem mass spectrometry results, anions with sodium counter-ions are more stable with respect to fragmentation under ion/ion proton transfer conditions than ions of the same charge state with protons counter-ions. Proton hydrates were found to give rise to much less anion fragmentation and constitute the softest protonation agents thus far identified for manipulating the charge states of multiply charged biopolymer anions. The reaction exothermicities associated with proton hydrates comprised of five or more water molecules are lower than that for protonated proton sponge, which is among the softest reagents thus far examined for ion/ion proton transfer reactions. The partitioning of ion/ion reaction exothermicity among all of the degrees of freedom of the products may also differ for proton hydrates relative to protonated molecules. However, a difference in energy partitioning need not be invoked to rationalize the results reported here.

  2. Surface-coupled proton exchange of a membrane-bound proton acceptor.

    PubMed

    Sandén, Tor; Salomonsson, Lina; Brzezinski, Peter; Widengren, Jerker

    2010-03-02

    Proton-transfer reactions across and at the surface of biological membranes are central for maintaining the transmembrane proton electrochemical gradients involved in cellular energy conversion. In this study, fluorescence correlation spectroscopy was used to measure the local protonation and deprotonation rates of single pH-sensitive fluorophores conjugated to liposome membranes, and the dependence of these rates on lipid composition and ion concentration. Measurements of proton exchange rates over a wide proton concentration range, using two different pH-sensitive fluorophores with different pK(a)s, revealed two distinct proton exchange regimes. At high pH (> 8), proton association increases rapidly with increasing proton concentrations, presumably because the whole membrane acts as a proton-collecting antenna for the fluorophore. In contrast, at low pH (< 7), the increase in the proton association rate is slower and comparable to that of direct protonation of the fluorophore from the bulk solution. In the latter case, the proton exchange rates of the two fluorophores are indistinguishable, indicating that their protonation rates are determined by the local membrane environment. Measurements on membranes of different surface charge and at different ion concentrations made it possible to determine surface potentials, as well as the distance between the surface and the fluorophore. The results from this study define the conditions under which biological membranes can act as proton-collecting antennae and provide fundamental information on the relation between the membrane surface charge density and the local proton exchange kinetics.

  3. Proton Therapy Verification with PET Imaging

    PubMed Central

    Zhu, Xuping; Fakhri, Georges El

    2013-01-01

    Proton therapy is very sensitive to uncertainties introduced during treatment planning and dose delivery. PET imaging of proton induced positron emitter distributions is the only practical approach for in vivo, in situ verification of proton therapy. This article reviews the current status of proton therapy verification with PET imaging. The different data detecting systems (in-beam, in-room and off-line PET), calculation methods for the prediction of proton induced PET activity distributions, and approaches for data evaluation are discussed. PMID:24312147

  4. Excited state of protonated benzene and toluene

    SciTech Connect

    Esteves-López, Natalia; Dedonder-Lardeux, Claude; Jouvet, Christophe

    2015-08-21

    We present photo-fragmentation electronic spectra of the simplest protonated aromatic molecules, protonated benzene and toluene, recorded under medium resolution conditions and compared with the photo-fragmentation spectrum of protonated pyridine. Despite the resolution and cold temperature achieved in the experiment, the electronic spectra of protonated benzene and toluene are structure-less, thus intrinsically broadened. This is in agreement with the large geometrical changes and the fast dynamic toward internal conversion predicted by ab initio calculations for protonated benzene [Rode et al., J. Phys. Chem. A 113, 5865–5873 (2009)].

  5. Proton conduction in biopolymer exopolysaccharide succinoglycan

    NASA Astrophysics Data System (ADS)

    Kweon, Jin Jung; Lee, Kyu Won; Kim, Hyojung; Lee, Cheol Eui; Jung, Seunho; Kwon, Chanho

    2014-07-01

    Protonic currents play a vital role in electrical signalling in living systems. It has been suggested that succinoglycan plays a specific role in alfalfa root nodule development, presumably acting as the signaling molecules. In this regard, charge transport and proton dynamics in the biopolymer exopolysaccharide succinoglycan have been studied by means of electrical measurements and nuclear magnetic resonance (NMR) spectroscopy. In particular, a dielectric dispersion in the system has revealed that the electrical conduction is protonic rather electronic. Besides, our laboratory- and rotating-frame 1H NMR measurements have elucidated the nature of the protonic conduction, activation of the protonic motion being associated with a glass transition.

  6. Compact proton spectrometers for measurements of shock

    SciTech Connect

    Mackinnon, A; Zylstra, A; Frenje, J A; Seguin, F H; Rosenberg, M J; Rinderknecht, H G; Johnson, M G; Casey, D T; Sinenian, N; Manuel, M; Waugh, C J; Sio, H W; Li, C K; Petrasso, R D; Friedrich, S; Knittel, K; Bionta, R; McKernan, M; Callahan, D; Collins, G; Dewald, E; Doeppner, T; Edwards, M J; Glenzer, S H; Hicks, D; Landen, O L; London, R; Meezan, N B

    2012-05-02

    The compact Wedge Range Filter (WRF) proton spectrometer was developed for OMEGA and transferred to the National Ignition Facility (NIF) as a National Ignition Campaign (NIC) diagnostic. The WRF measures the spectrum of protons from D-{sup 3}He reactions in tuning-campaign implosions containing D and {sup 3}He gas; in this work we report on the first proton spectroscopy measurement on the NIF using WRFs. The energy downshift of the 14.7-MeV proton is directly related to the total {rho}R through the plasma stopping power. Additionally, the shock proton yield is measured, which is a metric of the final merged shock strength.

  7. Proton conduction in biopolymer exopolysaccharide succinoglycan

    SciTech Connect

    Kweon, Jin Jung; Lee, Kyu Won; Kim, Hyojung; Lee, Cheol Eui; Jung, Seunho; Kwon, Chanho

    2014-07-07

    Protonic currents play a vital role in electrical signalling in living systems. It has been suggested that succinoglycan plays a specific role in alfalfa root nodule development, presumably acting as the signaling molecules. In this regard, charge transport and proton dynamics in the biopolymer exopolysaccharide succinoglycan have been studied by means of electrical measurements and nuclear magnetic resonance (NMR) spectroscopy. In particular, a dielectric dispersion in the system has revealed that the electrical conduction is protonic rather electronic. Besides, our laboratory- and rotating-frame {sup 1}H NMR measurements have elucidated the nature of the protonic conduction, activation of the protonic motion being associated with a glass transition.

  8. Rupture Process of the Tonga Earthquakes of 3 May 2006 (Mw 8.0) and 19 March 2009 (Mw 7.6): Intraslab Thrust Deformation Below the Megathrust

    NASA Astrophysics Data System (ADS)

    Meng, Q.; Ye, L.; Lay, T.; Cummins, P. R.

    2014-12-01

    The Tonga subduction zone is one of the most seismically active areas in the world, with a high rate of plate convergence between the subducting Pacific plate and the Tonga arc from 15°S to 25°S.However, seismically recorded large interplate thrusting events along the arc have not been larger than about Mw 8.0, and the degree of interplate seismic coupling has been inferred to vary from moderate to very low going from northern Tonga to southern Tonga [e.g., Scholz and Campos, 2012]. The possibility of this region experiencing a low probability maximum magnitude event of Mw8.57 up to 9.14 has been raised, but a paucity of geodetic observations and their distance from the Tonga trench have precluded assessments of slip deficit accumulation on the megathrust [Wallace et al., 2005]. Faulting mechanisms of historical large shallow earthquakes are uncertain [e.g., Okal et al., 2011], and some recent large events have been normal faulting or thrust-faulting intraslab events, so catalog-based assessments of seismic coupling are uncertain. Two recent large thrust-faulting earthquakes in 2006 and 2009 further complicate such assessments. The 3 May 2006 Mw8.0 event was located 100km west of the trench and caused a substantial regional tsunami, so it is sometimes assumed to be an interplate rupture. However, finite-fault modeling of teleseismic body waves supports a slip distribution centered about 60 km depth, consistent with centroid depths from W-phase (60.5 km) and global CMT (65 km) inversions. This was an intraslab thrust event with estimated stress drop of ~10 MPa. The fault plane is difficult to resolve unambiguously using teleseismic body waves, but joint inversion with static offsets from local GPS stations favors a shallow-dipping plane subparallel to the megathrust, or possibly a steeply dipping plane with triggered megathrust faulting. The 19 March 2009 Mw 7.6 thrust event occurred below the trench, and finite-fault and W-phase inversions indicate a 45km deep

  9. Tuning Proton Conductivity by Interstitial Guest Change in Size-Adjustable Nanopores of a Cu(I) -MOF: A Potential Platform for Versatile Proton Carriers.

    PubMed

    Khatua, Sajal; Kumar Bar, Arun; Konar, Sanjit

    2016-11-02

    By exploiting the breathing behavior of nanopores, we have studied for the first time the dependency of the guest-induced proton conductivity of an interpenetrated Cu(I) metal-organic framework (Cu(I) -MOF, [1]) on various guest molecules. Proton conductivities of over 10(-3)  S cm(-1) under humid conditions were induced by a series of guest molecules, namely N,N-dimethylformamide, dimethyl sulfoxide, diethylamine, 1,4-dinitrobenzene, nitrobenzene, pyridine, and 1H-1,2,4-triazole. A detailed investigation of the guest-incorporated complexes revealed that low-energy proton conduction occurs under humid conditions through the Grotthuss mechanism in [1⊃NB] and through the vehicle mechanism in the rest of the complexes. Single-point energy computations revealed considerable stabilization upon guest encapsulation. To the best of our knowledge, [1] represents the first example in which considerably high protonic conductivity is triggered upon the facile incorporation of small molecules of such a variety. The investigation portrayed herein may be a stepping stone towards the rational design of proton-conducting materials for practical applications.

  10. Shielding measurements for a 230 MeV proton beam

    SciTech Connect

    Siebers, J.V.

    1990-01-01

    Energetic secondary neutrons produced as protons interact with accelerator components and patients dominate the radiation shielding environment for proton radiotherapy facilities. Due to the scarcity of data describing neutron production, attenuation, absorbed dose, and dose equivalent values, these parameters were measured for 230 MeV proton bombardment of stopping length Al, Fe, and Pb targets at emission angles of 0{degree}, 22{degree}, 45{degree}, and 90{degree} in a thick concrete shield. Low pressure tissue-equivalent proportional counters with volumes ranging from 1 cm{sup 3} to 1000 cm{sup 3} were used to obtain microdosimetric spectra from which absorbed dose and radiation quality are deduced. Does equivalent values and attenuation lengths determined at depth in the shield were found to vary sharply with angle, but were found to be independent of target material. Neutron dose and radiation length values are compared with Monte Carlo neutron transport calculations performed using the Los Alamos High Energy Transport Code (LAHET). Calculations used 230 MeV protons incident upon an Fe target in a shielding geometry similar to that used in the experiment. LAHET calculations overestimated measured attenuation values at 0{degree}, 22{degree}, and 45{degree}, yet correctly predicted the attenuation length at 90{degree}. Comparison of the mean radiation quality estimated with the Monte Carlo calculations with measurements suggest that neutron quality factors should be increased by a factor of 1.4. These results are useful for the shielding design of new facilities as well as for testing neutron production and transport calculations.

  11. Calibration of CR-39 with monoenergetic protons

    NASA Astrophysics Data System (ADS)

    Xiaojiao, Duan; Xiaofei, Lan; Zhixin, Tan; Yongsheng, Huang; Shilun, Guo; Dawei, Yang; Naiyan, Wang

    2009-10-01

    Calibration of solid state nuclear track detector CR-39 was carried out with very low-energy monoenergetic protons of 20-100 keV from a Cockcroft Walton accelerator. To reduce the beam of the proton from the accelerator, a novel method was adopted by means of a high voltage pulse generator. The irradiation time of the proton beam on each CR-39 sheet was shortened to one pulse with duration of 100 ns, so that very separated proton tracks around 104 cm-2 can be irradiated and observed and measured on the surface of the CR-39 detector after etching. The variations of track diameter with etching time as well as with proton energy response curve has been carefully calibrated for the first time in this very low energy region. The calibration shows that the optical limit for the observation of etched tracks of protons in CR-39 is about or a little lower that 20 keV, above which the proton tracks can be seen clearly and the response curve can be used to distinguish protons from the other ions and determine the energy of the protons. The extension of response curve of protons from traditionally 20 to 100 keV in CR-39 is significant in retrieving information of protons produced in the studies of nuclear physics, plasma physics, ultrahigh intensity laser physics and laser acceleration.

  12. ACCELERATING POLARIZED PROTONS TO HIGH ENERGY.

    SciTech Connect

    BAI, M.; AHRENS, L.; ALEKSEEV, I.G.; ALESSI, J.; BEEBE-WANG, J.; BLASKIEWICZ, M.; BRAVAR, A.; BRENNAN, J.M.; BRUNO, D.; BUNCE, G.; ET AL.

    2006-10-02

    The Relativistic Heavy Ion Collider (RHIC) is designed to provide collisions of high energy polarized protons for the quest of understanding the proton spin structure. Polarized proton collisions at a beam energy of 100 GeV have been achieved in RHIC since 2001. Recently, polarized proton beam was accelerated to 250 GeV in RHIC for the first time. Unlike accelerating unpolarized protons, the challenge for achieving high energy polarized protons is to fight the various mechanisms in an accelerator that can lead to partial or total polarization loss due to the interaction of the spin vector with the magnetic fields. We report on the progress of the RHIC polarized proton program. We also present the strategies of how to preserve the polarization through the entire acceleration chain, i.e. a 200 MeV linear accelerator, the Booster, the AGS and RHIC.

  13. Very energetic protons in Saturn's radiation belt

    NASA Technical Reports Server (NTRS)

    Fillius, W.; Mcilwain, C.

    1980-01-01

    Very energetic protons are trapped in the inner Saturnian radiation belt. The University of California at San Diego instrument on Pioneer 11 has definitely identified protons of energy greater than 80 MeV on channel M3 and has tentatively detected protons of energy greater than 600 MeV on channel C3. The spatial distribution of the protons is distinct from that of the trapped electrons, the main difference being that the protons are strongly absorbed by the innermost moons and that the electrons are not. The source strength for injecting protons by the decay of cosmic ray albedo neutrons generated in the rings of Saturn has been estimated. The required proton lifetime is approximately 20 years.

  14. Clinical controversies: proton therapy for prostate cancer.

    PubMed

    Mouw, Kent W; Trofimov, Alexei; Zietman, Anthony L; Efstathiou, Jason A

    2013-04-01

    Proton therapy has been used in the treatment of prostate cancer for several decades, and interest surrounding its use continues to grow. Proton-based treatment techniques have evolved significantly over this period, and several centers now routinely use technologies such as pencil-beam scanning. However, whether the theoretical dosimetric advantages of the proton beam translate into clinically meaningful improvements for prostate cancer patients is unknown, and outcomes from single-arm experiences using whole courses of proton beam therapy in the treatment of early-stage prostate cancer have shown mixed results when compared with contemporary intensity-modulated radiotherapy. A randomized trial comparing proton beam therapy with intensity-modulated radiotherapy in early-stage disease has been launched and will be important in defining the role for proton therapy in this setting. We review the available evidence and present the current state of proton beam therapy for prostate cancer.

  15. Dynamic Protonation Equilibrium of Solvated Acetic Acid

    SciTech Connect

    Gu, Wei; Frigato, Tomaso; Straatsma, TP; Helms, Volkhard H.

    2007-04-13

    For the first time, the dynamic protonation equilibrium between an amino acid side chain analogue and bulk water as well as the diffusion properties of the excess proton were successfully reproduced through unbiased computer simulations. During a 50 ns Q-HOP MD simulation, two different regimes of proton transfer were observed. Extended phases of frequent proton swapping between acetic acid and nearby water were separated by phases where the proton freely diffuses in the simulation box until it is captured again by acetic acid. The pKa of acetic acid was calculated around 3.0 based on the relative population of protonated and deprotonated states and the diffusion coefficient of excess proton was computed from the average mean squared displacement in the simulation. Both calculated values agree well with the experimental measurements.

  16. Proton emission - new results and future prospects

    NASA Astrophysics Data System (ADS)

    Page, R. D.

    2016-09-01

    Proton emission is the radioactive decay mode that is expected to determine the limit of observable proton-rich nuclei for most elements. Considerable progress has been made in the study of proton-emitting nuclei since the first observation of direct proton emission nearly 50 years ago. This has led to improvements in our understanding of this decay process and provided invaluable nuclear structure data far from the valley of beta stability. The rapid fall in half-lives with increasing neutron deficiency when proton emission dominates makes it likely that for some elements, the lightest isotopes whose ground states can be observed in conventional experiments have already been reached. The enhanced stability against proton emission of the recently discovered high-lying isomer in 158Ta raises the possibility that proton emission from multiparticle isomers could be observed in nuclei beyond the expected boundaries of the nuclear landscape.

  17. PRESSURE FLUCTUATION BEHAVIOR IN THE CRYOGENIC HYDROGEN SYSTEM CAUSED BY A 100 kW PROTON BEAM INJECTION

    SciTech Connect

    Tatsumoto, H.; Aso, T.; Ohtsu, K.; Uehara, T.; Sakurayama, H.; Kawakami, Y.; Kato, T.; Hasegawa, S.; Futakawa, M.

    2010-04-09

    Supercritical hydrogen (1.5 MPa and around 20 K) has been selected as a moderator material for the intense spallation neutron source (JSNS) in J-PARC. The cryogenic hydrogen system provides the supercritical hydrogen for the moderators and removes the nuclear heating at the moderators, which is estimated to be 3.8 kW for a proton beam power of 1 MW. The pressure control system was designed to mitigate pressure fluctuation caused by suddenly turning a proton beam on and off, which is composed of a heater as an active controller for thermal compensation and an accumulator as a passive volume controller. A 109 kW proton beam was injected to the JSNS in December 2007. The pressure fluctuation behaviors were studied for the 109 kW proton beam operation. As soon as the proton beam was injected, the accumulator spontaneously started to constrict. The heater control succeeded in maintaining a constant heat load applied to the cryogenic hydrogen system. The pressure control system successfully reduced the pressure fluctuation within 6 kPa. It was confirmed that the pressure control system was effective.

  18. The electronic nature of the 1,4-β-glycosidic bond and its chemical environment: DFT insights into cellulose chemistry.

    PubMed

    Loerbroks, Claudia; Rinaldi, Roberto; Thiel, Walter

    2013-11-25

    The molecular understanding of the chemistry of 1,4-β-glucans is essential for designing new approaches to the conversion of cellulose into platform chemicals and biofuels. In this endeavor, much attention has been paid to the role of hydrogen bonding occurring in the cellulose structure. So far, however, there has been little discussion about the implications of the electronic nature of the 1,4-β-glycosidic bond and its chemical environment for the activation of 1,4-β-glucans toward acid-catalyzed hydrolysis. This report sheds light on these central issues and addresses their influence on the acid hydrolysis of cellobiose and, by analogy, cellulose. The electronic structure of cellobiose was explored by DFT at the BB1 K/6-31++G(d,p) level. Natural bond orbital (NBO) analysis was performed to grasp the key bonding concepts. Conformations, protonation sites, and hydrolysis mechanisms were examined. The results for cellobiose indicate that cellulose is protected against hydrolysis not only by its supramolecular structure, as currently accepted, but also by its electronic structure, in which the anomeric effect plays a key role.

  19. Fate of 1,4-dioxane in the aquatic environment: from sewage to drinking water.

    PubMed

    Stepien, Daria K; Diehl, Peter; Helm, Johanna; Thoms, Alina; Püttmann, Wilhelm

    2014-01-01

    Potential health effects of 1,4-dioxane and the limited data on its occurrence in the water cycle command for more research. In the current study, mobility and persistence of 1,4-dioxane in the sewage-, surface-, and drinking water was investigated. The occurrence of 1,4-dioxane was determined in wastewater samples from four domestic sewage treatment plants (STP). The influent and effluent samples were collected during weekly campaigns. The average influent concentrations in all four plants ranged from 262 ± 32 ng L(-1) to 834 ± 480 ng L(-1), whereas the average effluent concentrations were between 267 ± 35 ng L(-1) and 62,260 ± 36,000 ng L(-1). No removal of 1,4-dioxane during water treatment was observed. Owing to its strong internal chemical bonding, 1,4-dioxane is considered non-biodegradable under conventional bio-treatment technologies. The source of increased 1,4-dioxane concentrations in the effluents was identified to originate from impurities in the methanol used in the postanoxic denitrification process in one of the STPs. In view of poor biodegradation in STPs, surface water samples were collected to establish an extent of 1,4-dioxane pollution. Spatial and temporal distribution of 1,4-dioxane in the Rivers Main, Rhine, and Oder was examined. Concentrations reaching 2200 ng L(-1) in the Oder River, and 860 ng L(-1) in both Main and Rhine River were detected. The average monthly load of 1,4-dioxane in the Rhine River was calculated to equal to 172 kg d(-1). In all rivers, concentration of 1,4-dioxane increased with distance from the spring and was found to negatively correlate with the discharge of the river. Additionally, bank filtration and drinking water samples from two drinking water facilities were analyzed for the presence of 1,4-dioxane. The raw water contained 650 ng L(-1)-670 ng L(-1) of 1,4-dioxane, whereas the concentration in the drinking water fell only to 600 ng L(-1) and 490 ng L(-1), respectively. Neither of the purification

  20. Proton spin: A topological invariant

    NASA Astrophysics Data System (ADS)

    Tiwari, S. C.

    2016-11-01

    Proton spin problem is given a new perspective with the proposition that spin is a topological invariant represented by a de Rham 3-period. The idea is developed generalizing Finkelstein-Rubinstein theory for Skyrmions/kinks to topological defects, and using non-Abelian de Rham theorems. Two kinds of de Rham theorems are discussed applicable to matrix-valued differential forms, and traces. Physical and mathematical interpretations of de Rham periods are presented. It is suggested that Wilson lines and loop operators probe the local properties of the topology, and spin as a topological invariant in pDIS measurements could appear with any value from 0 to ℏ 2, i.e. proton spin decomposition has no meaning in this approach.

  1. Proton emission from triaxial nuclei

    SciTech Connect

    Delion, D.S.; Wyss, R.; Karlgren, D.; Liotta, R.J.

    2004-12-01

    Proton decay from triaxially deformed nuclei is investigated. The deformation parameters corresponding to the mother nucleus are determined microscopically and the calculated decay widths are used to probe the mean-field wave function. The proton wave function in the mother nucleus is described as a resonant state in a coupled-channel formalism. The decay width, as well as the angular distribution of the decaying particle, are evaluated and their dependence upon the triaxial deformation parameters is studied in the decay of {sup 161}Re and {sup 185}Bi. It is found that the decay width is very sensitive to the parameters defining the triaxial deformation while the angular distribution is a universal function which does not depend upon details of the nuclear structure.

  2. Monitoring proton therapy with PET

    PubMed Central

    El Fakhri, G

    2015-01-01

    Protons are being used in radiation therapy because of typically better dose conformity and reduced total energy deposited in the patient as compared with photon techniques. Both aspects are related to the finite range of a proton beam. The finite range also allows advanced dose shaping. These benefits can only be fully utilized if the end of range can be predicted accurately in the patient. The prediction of the range in tissue is associated with considerable uncertainties owing to imaging, patient set-up, beam delivery, interfractional changes in patient anatomy and dose calculation. Consequently, a significant range (of the order of several millimetres) is added to the prescribed range in order to ensure tumour coverage. Thus, reducing range uncertainties would allow a reduction of the treatment volume and reduce dose to potential organs at risk. PMID:25989699

  3. Proton Decay Searches with DUNE

    NASA Astrophysics Data System (ADS)

    Wood, Kevin

    2017-01-01

    The Deep Underground Neutrino Experiment (DUNE) will be comprised of a beam line and near detector complex at Fermilab, Illinois as well as a massive far detector located 1300 km away at Sanford Underground Research Facility (SURF), South Dakota. To achieve its rich physics program, DUNE plans to construct a 40kt fiducial volume Liquid Argon Time Projection Chamber (LArTPC) far detector almost a mile underground. The size, location, and technology of the proposed far detector make it an attractive tool to search for proton decay, which has yet to be observed. Observation of such a rare event requires high sensitivity to the signal and high background rejection rate. A particular background of interest arises from cosmic muons interacting with rock surrounding the detector and producing a variety of particles which can enter the detector and leave signatures similar to that of proton decay. In order to keep this background to a reasonable level without sacrificing signal acceptance efficiency, precise tracking, made possible by the LArTPC technology, is required. Precise 3D localization of proton decay events relies on the detector's ability to identify the prompt emission of scintillation light from proton decay events as the t0-defining signal. Therefore, low background rate and high detection efficiency of this light are the crucial to the search. This work examines these characteristics in a detailed Monte Carlo simulation using DUNE`s far detector reference design and demonstrates a high signal efficiency while keeping the expected number of cosmogenic background events sufficiently low.

  4. Proton Resonance Spectroscopy -- Final Report

    SciTech Connect

    Shriner, Jr, J F

    2009-07-27

    This report summarizes work supported by the DOE Grant DE-FG02-96ER40990 during its duration from June 1996 to May 2009. Topics studied include (1) statistical descriptions of nuclear levels and measurements of proton resonances relevant to such descriptions, including measurements toward a complete level scheme for 30P, (2) the development of methods to estimate the missing fraction of levels in a given measurement, and (3) measurements at HRIBF relevant to nuclear astrophysics.

  5. Proton synchrotron radiation at Fermilab

    SciTech Connect

    Thurman-Keup, Randy; /Fermilab

    2006-05-01

    While protons are not generally associated with synchrotron radiation, they do emit visible light at high enough energies. This paper presents an overview of the use of synchrotron radiation in the Tevatron to measure transverse emittances and to monitor the amount of beam in the abort gap. The latter is necessary to ensure a clean abort and prevent quenches of the superconducting magnets and damage to the silicon detectors of the collider experiments.

  6. Proton Scattering on Liquid Argon

    NASA Astrophysics Data System (ADS)

    Bouabid, Ryan; LArIAT Collaboration

    2017-01-01

    LArIAT (Liquid Argon In A Test-beam) is a liquid argon time projection chamber (LArTPC) positioned in a charged particle beamline whose primary purpose is to study the response of LArTPC's to charged particle interactions. This previously unmeasured experimental data will allow for improvement of Monte Carlo simulations and development of identification techniques, important for future planned LArTPC neutrino experiments. LArIAT's beamline is instrumented to allow for the identification of specific particles as well as measurement of those particles' incoming momenta. Among the particles present in the beamline, the analysis presented here focuses on proton-Argon interactions. This study uses particle trajectories and calorimetric information to identify proton-Argon interaction candidates. We present preliminary data results on the measurement of the proton-Argon cross-section. Liquid Argon In A Test Beam. The work is my analysis made possible through the efforts of LArIAT detector, data, and software.

  7. Solid-state proton conductors

    NASA Astrophysics Data System (ADS)

    Jewulski, J. R.; Osif, T. L.; Remick, R. J.

    1990-12-01

    The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling, and optimization studies. Correlation and optimization studies are described which include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells are presented which include the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms.

  8. Solid-state proton conductors

    SciTech Connect

    Jewulski, J.R.; Osif, T.L.; Remick, R.J.

    1990-12-01

    The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling and optimization studies. Correlation and optimization studies, to include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells including the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms. 164 refs., 27 figs., 13 tabs.

  9. Family symmetries and proton decay

    SciTech Connect

    Murayama, Hitoshi |; Kaplan, D.B.

    1994-08-01

    The proton decay modes p {yields} K{sup 0}e{sup +} and p {yields} K{sup 0}{mu}{sup +} may be visible in certain supersymmetric theories, and if seen would provide evidence for new flavor physics at extremely short distances. These decay modes can arise from the dimension five operator (Q{sub 1}Q{sub 1}Q{sub 2}L{sub 1,2}), where Q{sub i} and L{sub i} are i{sup th} generation quark and lepton superfields respectively. Such an operator is not generated at observable levels due to gauge or Higgs boson exchange in a minimal GUT. However in theories that explain the fermion mass hierarchy, it may be generated at the Planck scale with a strength such that the decays p {yields} K{sup 0}{ell}{sup +} are both compatible with the proton lifetime and visible at Super-Kamiokande. Observable proton decay can even occur in theories without unification.

  10. Identification of Biomarker Genes To Predict Biodegradation of 1,4-Dioxane

    PubMed Central

    Gedalanga, Phillip B.; Pornwongthong, Peerapong; Mora, Rebecca; Chiang, Sheau-Yun Dora; Baldwin, Brett; Ogles, Dora

    2014-01-01

    Bacterial multicomponent monooxygenase gene targets in Pseudonocardia dioxanivorans CB1190 were evaluated for their use as biomarkers to identify the potential for 1,4-dioxane biodegradation in pure cultures and environmental samples. Our studies using laboratory pure cultures and industrial activated sludge samples suggest that the presence of genes associated with dioxane monooxygenase, propane monooxygenase, alcohol dehydrogenase, and aldehyde dehydrogenase are promising indicators of 1,4-dioxane biotransformation; however, gene abundance was insufficient to predict actual biodegradation. A time course gene expression analysis of dioxane and propane monooxygenases in Pseudonocardia dioxanivorans CB1190 and mixed communities in wastewater samples revealed important associations with the rates of 1,4-dioxane removal. In addition, transcripts of alcohol dehydrogenase and aldehyde dehydrogenase genes were upregulated during biodegradation, although only the aldehyde dehydrogenase was significantly correlated with 1,4-dioxane concentrations. Expression of the propane monooxygenase demonstrated a time-dependent relationship with 1,4-dioxane biodegradation in P. dioxanivorans CB1190, with increased expression occurring after over 50% of the 1,4-dioxane had been removed. While the fraction of P. dioxanivorans CB1190-like bacteria among the total bacterial population significantly increased with decrease in 1,4-dioxane concentrations in wastewater treatment samples undergoing active biodegradation, the abundance and expression of monooxygenase-based biomarkers were better predictors of 1,4-dioxane degradation than taxonomic 16S rRNA genes. This study illustrates that specific bacterial monooxygenase and dehydrogenase gene targets together can serve as effective biomarkers for 1,4-dioxane biodegradation in the environment. PMID:24632253

  11. RCAN1-4 is a thyroid cancer growth and metastasis suppressor

    PubMed Central

    Wang, Chaojie; Saji, Motoyasu; Justiniano, Steven E.; Yusof, Adlina Mohd; Zhang, Xiaoli; Yu, Lianbo; Fernández, Soledad; Wakely, Paul; La Perle, Krista; Nakanishi, Hiroshi; Pohlman, Neal

    2017-01-01

    Metastasis suppressors are key regulators of tumor growth, invasion, and metastases. Loss of metastasis suppressors has been associated with aggressive tumor behaviors and metastatic progression. We previously showed that regulator of calcineurin 1, isoform 4 (RCAN1-4) was upregulated by the KiSS1 metastatic suppression pathway and could inhibit cell motility when overexpressed in cancer cells. To test the effects of endogenous RCAN1-4 loss on thyroid cancer in vivo, we developed RCAN1-4 knockdown stable cells. Subcutaneous xenograft models demonstrated that RCAN1-4 knockdown promotes tumor growth. Intravenous metastasis models demonstrated that RCAN1-4 loss promotes tumor metastases to the lungs and their subsequent growth. Finally, stable induction of RCAN1-4 expression reduced thyroid cancer cell growth and invasion. Microarray analysis predicted that nuclear factor, erythroid 2-like 3 (NFE2L3) was a pivotal downstream effector of RCAN1-4. NFE2L3 overexpression was shown to be necessary for RCAN1-4–mediated enhanced growth and invasiveness and NEF2L3 overexpression independently increased cell invasion. In human samples, NFE2L3 was overexpressed in TCGA thyroid cancer samples versus normal tissues and NFE2L3 overexpression was demonstrated in distant metastasis samples from thyroid cancer patients. In conclusion, we provide the first evidence to our knowledge that RCAN1-4 is a growth and metastasis suppressor in vivo and that it functions in part through NFE2L3. PMID:28289712

  12. Lymphocyte responses to DR1/4 restricted peptides in rheumatoid arthritis.

    PubMed Central

    Skinner, M A; Watson, L; Geursen, A; Tan, P L

    1994-01-01

    OBJECTIVE--To determine whether analog and unrelated DR1/4 binding peptides alter DR1/4 restricted responses of peripheral blood lymphocytes (PBL) from patients with rheumatoid arthritis (RA). METHODS--PBL from 25 patients with RA and 12 healthy controls were cultured with DR1/4 restricted peptides of the influenza haemagglutinin, amino acids 307-319 (HA) and matrix proteins, amino acids 17-29 (IM). Responses were determined by 3H-thymidine uptake proliferation assays and limiting dilution analysis. Competitor peptides were analogs HA-R312 and HA-K313 differing from HA by one amino acid at the 312 or 313 position respectively or unrelated peptides which bind to DR1/4. RESULTS--The responses of eight patients with RA to the two stimulatory influenza peptides did not differ significantly from controls and this was confirmed by the frequency estimate of T cells in PBL which responded to HA (mean frequency: 1 in 9.0 x 10(4), n = 5, in DR1/4+ RA patients, 1 in 7.6 x 10(4), n = 5, in DR1/4+ healthy controls). DR1/4 binding analogs of the HA peptide inhibited HA specific peptide responses of PBL from patients with RA and controls. Inhibition was also detected with unrelated peptides which bind to DR1/4 but to which the individual did not respond. CONCLUSION--Similar responses to two DR1/4 restricted peptides were observed in patients with RA and controls. Both antigen analog- and unrelated peptide-major histocompatibility complexes (MHC) can result in the inhibition of antigen specific responses in multi-clonal human lymphocyte populations. However, an analog peptide may be stimulatory in some individuals. These results provide some initial data for the development of a rational approach to MHC-specific immunomodulation in rheumatoid arthritis. Images PMID:8154934

  13. Rupture processes of the 2015 Mw 7.9 Gorkha earthquake and its Mw 7.3 aftershock and their implications on the seismic risk

    NASA Astrophysics Data System (ADS)

    Liu, Chengli; Zheng, Yong; Wang, Rongjiang; Shan, Bin; Xie, Zujun; Xiong, Xiong; Ge, Can

    2016-07-01

    The rupture processes of the 2015 April 25 Gorkha earthquake and its strongest aftershock occurred on May 12 in Nepal are investigated by joint inversion of seismological and geodetic data. Synthetic test shows that the sedimentary layers in the source region play an important role in the rupture process inversion. Our optimized model of the mainshock shows that the rupture has a unilateral propagation pattern. The dominant mechanism is pure thrust with maximum slip of 5.8 m, the rupture scale extends 60 km along dip and 150 km along strike, and the largest static stress change is 7.6 MPa. The total seismic moment is 7.87 × 1020 N m, equivalent to Mw 7.9. Most seismic moment was released within 80 s and the majority seismic moment was released at the first 40 s. The rupture propagated in main slip asperity with a velocity of 3.0 km/s. The strong aftershock magnitude is about Mw 7.3, and the peak slip is about 5.0 m, close to the peak slip of the mainshock. Moreover, the slips of the mainshock and the aftershocks are in good complementary, suggesting a triggering relationship between them. Considering the strain accumulation, the Gorkha earthquake ruptured only part of the seismic gap alone, thus still poses high earthquake risk, especially in the west side of the mainshock rupture zone.

  14. 1,4-Benzodiazepine drugs adsorption on the Ag colloidal surface

    NASA Astrophysics Data System (ADS)

    Cîntã, S.; Iliescu, T.; Astilean, S.; David, L.; Cozar, O.; Kiefer, W.

    1999-05-01

    The adsorption behaviour in the SERS complex of diazepam (7-chloro-1-methyl-5-phenyl-3-dihydro-1,4-benzodiazepin-2-one) and nitrazepam (1,3-dihydro-7-nitro-5-phenyl-1,4-benzodiazepin-2-one) with the Ag colloidal particles is reported and discussed. In both cases, the CN bond vibration of the 1,4-benzodiazepine is strongly affected by adsorption and enhanced. The SERS system of Ag colloid with diazepam or nitrazepam allow the recognition of the drug sample at concentration of 10 -7 mol l -1.

  15. Synthesis and antiinflammatory activity of 6-Acylsubstituted benzo-1,4-dioxanes and dihydrobenzopyrans

    SciTech Connect

    Daukshas, V.K.; Brukshtus, A.B.; Gaidyalis, P.G.; Pyatrauskas, O.Yu.; Udrenaite, E.B.

    1986-07-01

    6-Acylsubstituted benzo-1,4-dioxanes and dihydrobenzopyrans were synthesized by the Friedel-Crafts reaction by the acylation of benzo-1,4-dioxane or corresponding dihydrobenzopyran with an acid chloride in the presence of anhydrous AlCl/sub 3/; the ketone was obtained by the hydrogenation of the chalcone using Raney nickel. The antiinflammatory activity was studied on experimental models of carragheen and bentonite edema of the foot of white rats. Results indicate that derivatives of benzo-1,4-dioxane and dihydrobenzopyran of the type studied show promise as antiinflammatory agents.

  16. Hydrogen consentration meter utilizing a diffusion tube composed of 2 1/4 C r

    DOEpatents

    Roy, Prodyot; Sandusky, David W.; Hartle, Robert T.

    1979-01-01

    A diffusion tube hydrogen meter for improving the sensitivity and response time for the measurement of hydrogen in liquid sodium. The improved hydrogen meter has a composite membrane composed of pure nickel sleeve fitted, for example, over a 2 1/4 Cr-1 Mo steel or niobium diffusion tube. Since the hydrogen permeation rate through 2 1/4 Cr-1 Mo steels is a factor of four higher than pure nickel, and the permeation rate of hydrogen through niobium is two orders of magnitude greater than the 2 1/4 Cr-1 Mo steel, this results in a decrease in response time and an increase in the sensitivity.

  17. Structure-activity relationships of receptor binding of 1,4-dihydropyridine derivatives.

    PubMed

    Takahashi, Daiki; Oyunzul, Luvsandorj; Onoue, Satomi; Ito, Yoshihiko; Uchida, Shinya; Simsek, Rahime; Gunduz, Miyase Gozde; Safak, Chiat; Yamada, Shizuo

    2008-03-01

    The present study was undertaken to investigate binding activity of synthesized 1,4-dihydropyridine (1,4-DHP) derivatives (Compounds 1--124) to 1,4-DHP calcium channel antagonist receptors in rat brain. Sixteen 1,4-DHP derivatives inhibited specific (+)-[3H]PN 200-110 binding in rat brain in a concentration-dependent manner with IC50 value of 0.43 to 3.49 microM. Scatchard analysis revealed that compounds 54, 69, 85, like nifedipine, caused a significant increase in apparent dissociation constant (Kd) for (+)-[3H]PN 200-110, while compounds 68, 69 and 80 caused a significant decrease in maximal number of bindings sites (Bmax). These data suggest that compounds 68, 69 and 80 exert longer-acting antagonistic effects of 1,4-DHP receptors than compounds 54, 69 and 85. The structure-activity relationship study has revealed that 1) ester groups in 3- and 5-positions are the most effective, 2) the aryl group in the 4-position of 1,4-DHP ring is the basic requirement for optimal activity, 3) position and type of electron-withdrawing groups on phenyl group at position 4 would affect the receptor-binding activity. Furthermore, compound 58 exerted alpha1 receptor binding activity, being 1.6 times greater than 1,4-DHP receptors. Compounds 81, 84, 91, 94, 106, 108 and 109 showed significant binding of ATP-sensitive potassium (K ATP) channel, and the binding activities of compounds 81, 84, 108 and 109 were 1.6--3.8 times greater than the binding activity for 1,4-DHP receptors. Compounds 91 and 106 had similar binding activity for K ATP channel and 1,4-DHP receptors. In conclusion, the present study has shown that novel 1,4-DHP derivatives exert relatively high binding affinity to 1,4-DHP receptors and has revealed new aspect of structure-activity relationships of 1,4-DHP derivatives, especially hexahydroquinoline derivatives.

  18. L-proline-catalyzed synthesis of highly functionalized multisubstituted 1,4-dihydropyridines.

    PubMed

    Jiang, Huanfeng; Mai, Ronghuan; Cao, Hua; Zhu, Qiuhua; Liu, Xiaohang

    2009-12-07

    Highly functionalized multisubstituted 1,4-dihydropyridines 5 have been concisely synthesized in moderate to good yields via L-proline-catalyzed one-pot multicomponent reactions (MCRs) of alkynoates or alkynones 1, amines 2, beta-dicarbonyl compounds 3 and aldehydes 4 under mild conditions. The MCR process involves hydroamination/Knoevenagel condensation/Michael-type addition/intramolecular cyclization processes and leads to the formation of 1,4-dihydropyridines 5. The molecular structure of 5ckaa was confirmed by single-crystal X-ray diffraction. This method is energy saving and environmentally friendly, providing easy access to diverse multisubstituted polyfunctional 1,4-dihydropyridines.

  19. Seismological analyses of the 2010 March 11, Pichilemu, Chile Mw 7.0 and Mw 6.9 coastal intraplate earthquakes

    USGS Publications Warehouse

    Ruiz, Javier A.; Hayes, Gavin P.; Carrizo, Daniel; Kanamori, Hiroo; Socquet, Anne; Comte, Diana

    2014-01-01

    On 2010 March 11, a sequence of large, shallow continental crust earthquakes shook central Chile. Two normal faulting events with magnitudes around Mw 7.0 and Mw 6.9 occurred just 15 min apart, located near the town of Pichilemu. These kinds of large intraplate, inland crustal earthquakes are rare above the Chilean subduction zone, and it is important to better understand their relationship with the 2010 February 27, Mw 8.8, Maule earthquake, which ruptured the adjacent megathrust plate boundary. We present a broad seismological analysis of these earthquakes by using both teleseismic and regional data. We compute seismic moment tensors for both events via a W-phase inversion, and test sensitivities to various inversion parameters in order to assess the stability of the solutions. The first event, at 14 hr 39 min GMT, is well constrained, displaying a fault plane with strike of N145°E, and a preferred dip angle of 55°SW, consistent with the trend of aftershock locations and other published results. Teleseismic finite-fault inversions for this event show a large slip zone along the southern part of the fault, correlating well with the reported spatial density of aftershocks. The second earthquake (14 hr 55 min GMT) appears to have ruptured a fault branching southward from the previous ruptured fault, within the hanging wall of the first event. Modelling seismograms at regional to teleseismic distances (Δ > 10°) is quite challenging because the observed seismic wave fields of both events overlap, increasing apparent complexity for the second earthquake. We perform both point- and extended-source inversions at regional and teleseismic distances, assessing model sensitivities resulting from variations in fault orientation, dimension, and hypocentre location. Results show that the focal mechanism for the second event features a steeper dip angle and a strike rotated slightly clockwise with respect to the previous event. This kind of geological fault configuration

  20. Crystal structure of dimethyl 2,5-bis-[(di-phen-oxy-phosphor-yl)-oxy]cyclo-hexa-1,4-diene-1,4-di-carboxyl-ate.

    PubMed

    Gao, Lei; Ma, Zongshan; Yan, Hong

    2015-06-01

    In the title compound, C34H30O12P2, which was synthesized via the esterification of dimethyl 2,5-dioxo-1,4-cyclo-hexa-nedi-carboxyl-ate with diphenyl chloro-phosphate, the mol-ecule has crystallographic inversion symmetry. The dihedral angles between the plane of the cyclo-hexa-1,4-diene ring and those of the two benzene rings of the substituent phosphate groups are 41.0 (1) and 89.5 (1)°, while that with the ester group is 3.1 (3)°. In the crystal, only weak inter-molecular C-H⋯O hydrogen bonds are present.