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Sample records for adenylate energy charge

  1. ADENYLATE ENERGY CHARGE AND ADENINE NUCLEOTIDE MEASUREMENTS AS INDICATORS OF STRESS IN THE MUSSEL, MYTILUS EDULIS, TREATED WITH DREDGED MATERIAL UNDER LABORATORY CONDITIONS

    Adenylate energy charge is an indication of the amount of energy available to an organism from the adenylate pool. t is calculated from measured concentrations of three adenine nucleotides, adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP...

  2. The adenylate energy charge as a new and useful indicator of capture stress in chondrichthyans.

    Guida, Leonardo; Walker, Terence I; Reina, Richard D

    2016-02-01

    Quantifying the physiological stress response of chondrichthyans to capture has assisted the development of fishing practices conducive to their survival. However, currently used indicators of stress show significant interspecific and intraspecific variation in species' physiological responses and tolerances to capture. To improve our understanding of chondrichthyan stress physiology and potentially reduce variation when quantifying the stress response, we investigated the use of the adenylate energy charge (AEC); a measure of available metabolic energy. To determine tissues sensitive to metabolic stress, we extracted samples of the brain, heart, liver, white muscle and blood from gummy sharks (Mustelus antarcticus) immediately following gillnet capture and after 3 h recovery under laboratory conditions. Capture caused significant declines in liver, white muscle and blood AEC, whereas no decline was detected in the heart and brain AEC. Following 3 h of recovery from capture, the AEC of the liver and blood returned to "unstressed" levels (control values) whereas white muscle AEC was not significantly different to that immediately after capture. Our results show that the liver is most sensitive to metabolic stress and white muscle offers a practical method to sample animals non-lethally for determination of the AEC. The AEC is a highly informative indicator of stress and unlike current indicators, it can directly measure the change in available energy and thus the metabolic stress experienced by a given tissue. Cellular metabolism is highly conserved across organisms and, therefore, we think the AEC can also provide a standardised form of measuring capture stress in many chondrichthyan species. PMID:26660290

  3. Signal-transduction protein P(II) from Synechococcus elongatus PCC 7942 senses low adenylate energy charge in vitro.

    Fokina, Oleksandra; Herrmann, Christina; Forchhammer, Karl

    2011-11-15

    P(II) proteins belong to a family of highly conserved signal-transduction proteins that occurs widely in bacteria, archaea and plants. They respond to the central metabolites ATP, ADP and 2-OG (2-oxoglutarate), and control enzymes, transcription factors and transport proteins involved in nitrogen metabolism. In the present study, we examined the effect of ADP on in vitro P(II)-signalling properties for the cyanobacterium Synechococcus elongatus, a model for oxygenic phototrophic organisms. Different ADP/ATP ratios strongly affected the properties of P(II) signalling. Increasing ADP antagonized the binding of 2-OG and directly affected the interactions of P(II) with its target proteins. The resulting P(II)-signalling properties indicate that, in mixtures of ADP and ATP, P(II) trimers are occupied by mixtures of adenylate nucleotides. Binding and kinetic activation of NAGK (N-acetyl-L-glutamate kinase), the controlling enzyme of arginine biosynthesis, by P(II) was weakened by ADP, but relief from arginine inhibition remained unaffected. On the other hand, ADP enhanced the binding of P(II) to PipX, a co-activator of the transcription factor NtcA and, furthermore, antagonized the inhibitory effect of 2-OG on P(II)-PipX interaction. These results indicate that S. elongatus P(II) directly senses the adenylate energy charge, resulting in target-dependent differential modification of the P(II)-signalling properties. PMID:21774788

  4. Charges of Nicotinamide Adenine nucleotides and Adenylate Energy Charge as regulatory parameters of the metabolism in Eschericia coli

    Andersen, Klaus Bahl; von Meyenburg, Kaspar

    1977-01-01

    NADH/(NADH+NAD), NADPH/(NADPH+NADP) and (ATP+½ADP)/(ATP+ADP+AMP) respectively has the values 0.05, 0.45 and 0.9 during steady state growth. The changes of the charges during changes of growth are examined.......NADH/(NADH+NAD), NADPH/(NADPH+NADP) and (ATP+½ADP)/(ATP+ADP+AMP) respectively has the values 0.05, 0.45 and 0.9 during steady state growth. The changes of the charges during changes of growth are examined....

  5. Measurement of the adenylate energy charge in Nereis diversicolor and Nephtys sp. (Polychaeta: Annelida): evaluation of the usefulness of AEC in pollution monitoring

    Verschraegen, K.; Herman, P.M.J.; Van Gansbeke, D.; Braeckman, A.

    1985-01-01

    ATP-content and adenylate energy charge (AEC) ratios were determined in two polychaete species (Nereis diversicolor and Nephtys sp.), sampled in ten stations along the heavily polluted Western Scheldt estuary (N. Belgium, S. Holland). The samples were taken between 27 December 1982 and 6 January 1983. Nereis diversicolor was also sampled in an unpolluted brackish water pond, and subjected to artificial stress by drying the organisms on filter paper. Adenine nucleotide levels were determined u...

  6. Alternative Respiration Induced by Glucose Stimulation and Variation of Adenylate Energy Charge in Glucose-Starved Cells of Green Alga Chlorella Protothecoides

    2001-01-01

    Effects of inhibitors and glucose on cytochrome and alternative respiration and on adenylate energy charge (AEC) in glucose-starved Chlorella protothecoides were investigated. 1 mmol/L azide (NaN3), which immediately caused an increase of O2 uptake by inhibiting the cytochrome pathway and stimulating alternative respiration, resulted in a decrease of AEC value from 0. 83 to 0. 34 within 3 minutes. When 1 mmol/L salicylhydroxamic acid (SHAM) was added into the cell suspension, there was no apparent variation in AEC. Adding NaN3 and SHAM together into cell suspension to inhibit both cytochrome and alternative pathways showed a same change of AEC as that of adding NaN3 alone. When 2.0 mmol/L of glucose was added to a suspension of glucose-starved cells, the O2 uptake rate was immediately stimulated from 0.81 up to 1.34 [μrnol/L O2 · min-] · (mL PCV)-1]. The respiration stimulated by glucose could be inhibited about 20% by adding 1 mmol/L SHAM. It was found by titration with SHAM in the absence and presence of NaN3 that 53% of O2 uptake went through the cytochrome pathway and 45% of the alternate pathway was operational in enhanced respiration. It implied that induced operation of the alternative respiratory pathway probably resulted from the burst of the electron flux into the electron transport chain by glucose stimulation.

  7. Adenylate Kinase and AMP Signaling Networks: Metabolic Monitoring, Signal Communication and Body Energy Sensing

    Andre Terzic

    2009-04-01

    Full Text Available Adenylate kinase and downstream AMP signaling is an integrated metabolic monitoring system which reads the cellular energy state in order to tune and report signals to metabolic sensors. A network of adenylate kinase isoforms (AK1-AK7 are distributed throughout intracellular compartments, interstitial space and body fluids to regulate energetic and metabolic signaling circuits, securing efficient cell energy economy, signal communication and stress response. The dynamics of adenylate kinase-catalyzed phosphotransfer regulates multiple intracellular and extracellular energy-dependent and nucleotide signaling processes, including excitation-contraction coupling, hormone secretion, cell and ciliary motility, nuclear transport, energetics of cell cycle, DNA synthesis and repair, and developmental programming. Metabolomic analyses indicate that cellular, interstitial and blood AMP levels are potential metabolic signals associated with vital functions including body energy sensing, sleep, hibernation and food intake. Either low or excess AMP signaling has been linked to human disease such as diabetes, obesity and hypertrophic cardiomyopathy. Recent studies indicate that derangements in adenylate kinase-mediated energetic signaling due to mutations in AK1, AK2 or AK7 isoforms are associated with hemolytic anemia, reticular dysgenesis and ciliary dyskinesia. Moreover, hormonal, food and antidiabetic drug actions are frequently coupled to alterations of cellular AMP levels and associated signaling. Thus, by monitoring energy state and generating and distributing AMP metabolic signals adenylate kinase represents a unique hub within the cellular homeostatic network.

  8. Cytosolic adenylate changes during exercise in prawn muscle

    31P NMR and biochemical analysis were used to assess the effect of heavy exercise on cytosolic adenylate levels in Palaemon serratus abdominal muscle. At rest, the MgATP level corresponded to 85.5% of the total ATP content. The cytosolic adenylate concentrations of the prawn muscle are considerably different from that of vertebrates. The percentage of ADP bound to myofilaments was lower in the prawn muscle. Consequently, the level of free cytosolic AMP was greatly higher (thirty fold higher) than in vertebrate muscle. During vigorous work, the concentration of MgATP dropped and the cytosolic AMP accumulated, while the cytosolic adenine nucleotide pool decreased significantly. The phosphorylation potential value and the ATP/ADP ratio, calculated from the cytosolic adenylate, dropped acutely during the whole period of muscular contractions. On the contrary, the adenylate energy charge calculated from the cytosolic adenylate decreased slightly. Therefore, even in muscle displaying no AMP deamination, the adenylate charge is stabilized during exercise by the dynamic changes between cytosolic and bound adenylate species. (author). 21 refs., 2 tabs

  9. Negatively charged residues of the segment linking the enzyme and cytolysin moieties restrict the membrane-permeabilizing capacity of adenylate cyclase toxin

    Masin, Jiri; Osickova, Adriana; Sukova, Anna; Fiser, Radovan; Halada, Petr; Bumba, Ladislav; Linhartova, Irena; Osicka, Radim; Sebo, Peter

    2016-01-01

    The whooping cough agent, Bordetella pertussis, secretes an adenylate cyclase toxin-hemolysin (CyaA) that plays a crucial role in host respiratory tract colonization. CyaA targets CR3-expressing cells and disrupts their bactericidal functions by delivering into their cytosol an adenylate cyclase enzyme that converts intracellular ATP to cAMP. In parallel, the hydrophobic domain of CyaA forms cation-selective pores that permeabilize cell membrane. The invasive AC and pore-forming domains of CyaA are linked by a segment that is unique in the RTX cytolysin family. We used mass spectrometry and circular dichroism to show that the linker segment forms α-helical structures that penetrate into lipid bilayer. Replacement of the positively charged arginine residues, proposed to be involved in target membrane destabilization by the linker segment, reduced the capacity of the toxin to translocate the AC domain across cell membrane. Substitutions of negatively charged residues then revealed that two clusters of negative charges within the linker segment control the size and the propensity of CyaA pore formation, thereby restricting the cell-permeabilizing capacity of CyaA. The ‘AC to Hly-linking segment’ thus appears to account for the smaller size and modest cell-permeabilizing capacity of CyaA pores, as compared to typical RTX hemolysins. PMID:27581058

  10. Mechanism of adenylate kinase. Is there a relationship between local substrate dynamics, local binding energy, and the catalytic mechanism?

    Adenylyl (β,γ-methylene)diphosphonic acid (AMPPCP) labeled with deuterium at the adenine ring ([8-2H]AMPPCP) and at the β,γ-methylene group (AMPPCD2P), as well as adenosine 5'-monophosphate labeled at the adenine ring ([8-2H]AMP), was synthesized and used for deuterium nuclear magnetic resonance (NMR) determination of effective correlation times (τc) of the free nucleotide and the complexes with adenylate kinase (AK). Extensive and rigorous control experiments and theoretical analysis were performed to justify the validity of the experimental approaches, particularly the fast exchange condition, and the reliability of the τc values obtained. For the free nucleotide, the results suggest that the phosphonate group of free AMPPCP possesses appreciable local mobility relative to the adenine ring and that complexation with Mg2+ greatly reduced such a local mobility. These results suggest that the adenine ring of substrates is rigidly bound in all cases, that the phosphonate chain of AMPPCP possesses considerable local mobility, and that Mg2+ reduces such local mobility but does not totally immobilize it. The results suggest that no general correlation exists between the local rigidity of portions of a bound substrate and the corresponding (ground state) local binding energy contributed by these portions. The authors have found that the Ki values for the mixture, the Δ isomer, and the Λ isomer of CrATP are 16, 11, and 20 μM, respectively, which suggest that ground-state binding by AK is stereochemically permissive. The results of both problems fully support the conclusion that the phosphonate chain of AK-MgAMPPCP possesses considerable local mobility and illuminate the relationship between the dynamics of bound substrates and the catalytic mechanism

  11. Signal transduction protein PII from Synechococcus elongatus PCC 7942 senses low adenylate energy charge in vitro.

    Fokina, Oleksandra; Herrmann, Christina; Forchhammer, Karl

    2011-01-01

    Abstract PII proteins belong to a family of highly conserved signal transduction proteins widely spread in bacteria, archaea and plants. They respond to the central metabolites ATP, ADP and 2-oxoglutarate (2-OG) and control enzymes, transcription factors and transport proteins involved in nitrogen metabolism. Here we studied the effect of ADP on in vitro PII signalling properties from the cyanobacterium Synechococcus elongatus, a model for oxygenic phototrophic organisms. Different...

  12. Medium energy charged particle spectrometer

    The charged particle spectrometer E8 on HELIOS A and B will be described in some detail. It covers proton energies from 80 keV to 6 MeV, electrons from 20 keV to 2 MeV, and positrons from 150 to 550 keV. Its flight performance will be discussed. From examples of measurements the capability of the instrument will be demonstrated. (orig.)

  13. Energy status parameters, hypoxia fraction and radiocurability across tumor types

    Under full nutrient in vitro conditions, the cellular adenylate energy charge of six different rodent and human tumor cell types was identical, i.e., 0.94 ± 0.01, suggesting the potential utility of this parameter as a cell (and tissue) independent marker of nutrient deprivation and hypoxia, across tumor types. The adenylate energy charge values of tumors, arising from these cells, was reduced and variable ranging from 0.72 to 0.91 for the various tumor types. However, neither the tumor adenylate energy charge, NTP/Pi, nor PCr/Pi ratios correlated with the radiobiologic hypoxic cell fractions across tumor types. The reduced adenylate energy charge in vivo suggests varying degrees of nutrient deprivation in the different tumor types, however, factors other than or in addition to hypoxia likely contribute to tumor energy status. (orig.)

  14. Examination of the relationship of substrate dynamics to enzymic structure, binding energy, and catalysis: NMR studies of adenosine 5'-triphosphate and adenylate kinase

    By measuring the deuterium NMR-relaxation rates of adenylyl (β, λ-methylene)diphosphonic acid (AMPPCP) labeled with deuterium at the adenine ring [8-2H]AMPPCP and upon the phosphonate chain (AMPPCD2P) free in solution and bound to the MgATP site of adenylate kinases (AK) the local motional dynamics of AMPPCP and MgAMPPCP in the two environments were established. The analysis of the experimental data involved the rigorous experimental verification that the systems studied were in the fast exchange limit on an NMR timescale. In addition analysis required careful examination of the equations describing quadrupolar relaxation, particularly the spectral density equations which contain information on molecular motion. Having determined the local dynamics of the nucleotides and their complexes with Mg + 2 free in solution and bound to AK and observing that MgAMPPCP is an excellent model for the natural substrate of AK, MgATP, we examined the relationship of local substrate dynamics to enzyme structure, binding energy, and catalysis

  15. Key Role of the Adenylate Moiety and Integrity of the Adenylate-Binding Site for the NAD(+)/H Binding to Mitochondrial Apoptosis-Inducing Factor.

    Sorrentino, Luca; Calogero, Alessandra Maria; Pandini, Vittorio; Vanoni, Maria Antonietta; Sevrioukova, Irina F; Aliverti, Alessandro

    2015-12-01

    Apoptosis-inducing factor (AIF) is a mitochondrial flavoprotein with pro-life and pro-death activities, which plays critical roles in mitochondrial energy metabolism and caspase-independent apoptosis. Defects in AIF structure or expression can cause mitochondrial abnormalities leading to mitochondrial defects and neurodegeneration. The mechanism of AIF-induced apoptosis was extensively investigated, whereas the mitochondrial function of AIF is poorly understood. A unique feature of AIF is the ability to form a tight, air-stable charge-transfer (CT) complex upon reaction with NADH and to undergo a conformational switch leading to dimerization, proposed to be important for its vital and lethal functions. Although some aspects of interaction of AIF with NAD(+)/H have been analyzed, its precise mechanism is not fully understood. We investigated how the oxidized and photoreduced wild-type and G307A and -E variants of murine AIF associate with NAD(+)/H and nicotinamide mononucleotide (NMN(+)/H) to determine the role of the adenylate moiety in the binding process. Our results indicate that (i) the adenylate moiety of NAD(+)/H is crucial for the association with AIF and for the subsequent structural reorganization of the complex, but not for protein dimerization, (ii) FAD reduction rather than binding of NAD(+)/H to AIF initiates conformational rearrangement, and (iii) alteration of the adenylate-binding site by the G307E (equivalent to a pathological G308E mutation in human AIF) or G307A replacements decrease the affinity and association rate of NAD(+)/H, which, in turn, perturbs CT complex formation and protein dimerization but has no influence on the conformational switch in the regulatory peptide. PMID:26535916

  16. Gravitational Binding Energy in Charged Cylindrical Symmetry

    Sharif, M

    2014-01-01

    We consider static cylindrically symmetric charged gravitating object with perfect fluid and investigate the gravitational binding energy. It is found that only the localized part of the mass function provides the gravitational binding energy, whereas the non-localized part generated by the electric coupling does not contribute for such energy.

  17. Energy storage device with large charge separation

    Holme, Timothy P.; Prinz, Friedrich B.; Iancu, Andrei

    2016-04-12

    High density energy storage in semiconductor devices is provided. There are two main aspects of the present approach. The first aspect is to provide high density energy storage in semiconductor devices based on formation of a plasma in the semiconductor. The second aspect is to provide high density energy storage based on charge separation in a p-n junction.

  18. Energy extremum principle for charged black holes

    Fraser, Scott; Funkhouser, Shaker Von Price

    2015-11-01

    For a set of N asymptotically flat black holes with arbitrary charges and masses, all initially at rest and well separated, we prove the following extremum principle: the extremal charge configuration (|qi|=mi for each black hole) can be derived by extremizing the total energy, for variations of the black hole apparent horizon areas, at fixed charges and fixed Euclidean separations. We prove this result through second order in an expansion in the inverse separations. If all charges have the same sign, this result is a variational principle that reinterprets the static equilibrium of the Majumdar-Papapetrou-Hartle-Hawking solution as an extremum of total energy, rather than as a balance of forces; this result augments a list of related variational principles for other static black holes, and is consistent with the independently known Bogomol'nyi-Prasad-Sommerfield (BPS) energy minimum.

  19. Pacemakers charging using body energy

    Dinesh Bhatia

    2010-01-01

    Full Text Available Life-saving medical implants like pacemakers and defibrillators face a big drawback that their batteries eventually run out and patients require frequent surgery to have these batteries replaced. With the advent of technology, alternatives can be provided for such surgeries. To power these devices, body energy harvesting techniques may be employed. Some of the power sources are patient′s heartbeat, blood flow inside the vessels, movement of the body parts, and the body temperature (heat. Different types of sensors are employed, such as for sensing the energy from the heartbeat the piezoelectric and semiconducting coupled nanowires are used that convert the mechanical energy into electricity. Similarly, for sensing the blood flow energy, nanogenerators driven by ultrasonic waves are used that have the ability to directly convert the hydraulic energy in human body to electrical energy. Another consideration is to use body heat employing biothermal battery to generate electricity using multiple arrays of thermoelectric generators built into an implantable chip. These generators exploit the well-known thermocouple effect. For the biothermal device to work, it needs a 2°C temperature difference across it. But there are many parts of the body where a temperature difference of 5°C exists - typically in the few millimeters just below the skin, where it is planned to place this device. This study focuses on using body heat as an alternative energy source to recharge pacemaker batteries and other medical devices and prevent the possibility of life-risk during repeated surgery.

  20. A Continuous Kinetic Assay for Adenylation Enzyme Activity and Inhibition

    Daniel J. Wilson; Aldrich, Courtney C.

    2010-01-01

    Adenylation/adenylate-forming enzymes catalyze the activation of a carboxylic acid at the expense of ATP to form an acyl-adenylate intermediate and pyrophosphate (PPi). In a second half-reaction, adenylation enzymes catalyze the transfer of the acyl moiety of the acyl-adenylate onto an acceptor molecule, which can be either a protein or a small molecule. We describe the design, development, and validation of a coupled continuous spectrophotometric assay for adenylation enzymes that employs hy...

  1. Charged Vaidya Solution Satisfies Weak Energy Condition

    Chatterjee, Soumyabrata; Virmani, Amitabh

    2015-01-01

    The external matter stress-tensor supporting charged Vaidya solution appears to violate weak energy condition in certain region of the spacetime. Motivated by this, a new interpretation of charged Vaidya solution was proposed by Ori [1] in which the energy condition continues to be satisfied. In this construction, one glues an outgoing Vaidya solution to the original ingoing Vaidya solution provided the surface where the external stress-tensor vanishes is spacelike. We revisit this study and extend it to higher-dimensions, to AdS settings, and to higher-derivative f(R) theories. In asymptotically flat space context, we explore in detail the case when the mass function m(v) is proportional to the charge function q(v). When the proportionality constant \

  2. Low energy charge capture cross sections

    This report surveys the available data on charge capture from atomic H by partially and completely stripped light ions, and partially stripped heavy ions. The energy range is nominally between 3 and 200 eV, although the scarcity of data for many species has meant that these limits are not always observed. Analytical fits to the available data are given. General theoretical considerations are discussed, and some results on the molecular potential energy diagrams and low energy capture for the C4+ + H and Ni3+ + H systems are given. (author)

  3. Regulation of brain adenylate cyclase by calmodulin

    This thesis examined the interaction between the Ca2+-binding protein, calmodulin (CaM), and the cAMP synthesizing enzyme, adenylate cyclase. The regulation of guanyl nucleotide-dependent adenylate cyclase by CaM was examined in a particulate fraction from bovine striatum. CaM stimulated basal adenylate cyclase activity and enhanced the stimulation of the enzyme by GTP and dopamine (DA). The potentiation of GTP- and DA-stimulated adenylate cyclase activities by CaM was more sensitive to the concentration of CaM than was the stimulation of basal activity. A photoreactive CaM derivative was developed in order to probe the interactions between CaM and the adenylate cyclase components of bovine brain. Iodo-[125I]-CaM-diazopyruvamide (125I-CAM-DAP) behaved like native CaM with respect to Ca2+-enhanced mobility on sodium dodecyl sulfate-polyacrylamide gels and Ca2+-dependent stimulation of adenylate cyclase. 125I-CaM-DAP cross-linked to CaM-binding proteins in a Ca2+-dependent, concentration-dependent, and CaM-specific manner. Photolysis of 125I-CaM-DAP and forskolin-agarose purified CaM-sensitive adenylate cyclase produced an adduct with a molecular weight of 140,000

  4. Uridylation and adenylation of RNAs.

    Song, JianBo; Song, Jun; Mo, BeiXin; Chen, XueMei

    2015-11-01

    The posttranscriptional addition of nontemplated nucleotides to the 3' ends of RNA molecules can have a significant impact on their stability and biological function. It has been recently discovered that nontemplated addition of uridine or adenosine to the 3' ends of RNAs occurs in different organisms ranging from algae to humans, and on different kinds of RNAs, such as histone mRNAs, mRNA fragments, U6 snRNA, mature small RNAs and their precursors etc. These modifications may lead to different outcomes, such as increasing RNA decay, promoting or inhibiting RNA processing, or changing RNA activity. Growing pieces of evidence have revealed that such modifications can be RNA sequence-specific and subjected to temporal or spatial regulation in development. RNA tailing and its outcomes have been associated with human diseases such as cancer. Here, we review recent developments in RNA uridylation and adenylation and discuss the future prospects in this research area. PMID:26563174

  5. Electrostatic vibration energy harvester with increased charging current

    The analysis of the operation of the electrostatic vibration energy harvester to charge self-contained power supply is carried out. An analytical expression to estimate the average charging current taking into account diode's reverse current is obtained. The ways to increase the charging current were found. The harvester with increased charging current containing no switches and inductive elements is suggested

  6. Electrostatic energy analyzers for high energy charged particle beams

    The electrostatic energy analyzers for high energy charged particle beams emitted from extended large-size objects as well as from remote point sources are proposed. Results of the analytical trajectory solutions in ideal cylindrical field provide focusing characteristics for both configurations. The instruments possess of simple compact design, based on an ideal cylindrical field with entrance window arranged in the end-boundary between electrodes and can be used for measurements in space technologies, plasma and nuclear physics

  7. Molecular cloning and amplification of the adenylate cyclase gene.

    Wang, J Y; Clegg, D O; Koshland, D E

    1981-01-01

    A segment of DNA containing cya, the gene for adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1], has been isolated from Salmonella typhimurium. The phage lambda gt4 was used as a cloning vector and adenylate cyclase-positive hybrid phages were isolated that complemented adenylate cyclase-negative bacteria. The cloned DNA fragment encodes a polypeptide of molecular weight 81,000 that gives rise to adenylate cyclase activity. This protein represents a functional mutant of the ...

  8. Charge independence and charge symmetry breaking interactions and the Coulomb energy anomaly in isobaric analog states

    Effects of CIB (charge independence breaking) and CSB (charge symmetry breaking) interactions on the Coulomb displacement energies of isobaric analog states are investigated for 48Ca, 90Zr and 208Pb. Mass number dependence of the Coulomb energy anomalies is well explained when CIB and CSB interactions are used which reproduce the differences of the scattering lengths as well as those of the effective ranges of low energy nucleon-nucleon scattering. (author) 17 refs., 3 figs., 3 tabs

  9. Ion momentum and energy transfer rates for charge exchange collisions

    Horwitz, J.; Banks, P. M.

    1973-01-01

    The rates of momentum and energy transfer have been obtained for charge exchange collisions between ion and neutral gases having arbitrary Maxwellian temperatures and bulk transport velocities. The results are directly applicable to the F-region of the ionosphere where 0+ - 0 charge is the dominant mechanism affecting ion momentum and energy transfer.

  10. Cooperative phenomena in binding and activation of Bordetella pertussis adenylate cyclase by calmodulin.

    Bouhss, A; Krin, E; Munier, H; Gilles, A M; Danchin, A; Glaser, P; Bârzu, O

    1993-01-25

    The catalytic domain of Bordetella pertussis adenylate cyclase located within the first 400 amino acids of the protein can be cleaved by trypsin in two subdomains (T25 and T18) corresponding to ATP-(T25) and calmodulin (CaM)-(T18) binding sites. Reassociation of subdomains by CaM is a cooperative process, which is a unique case among CaM-activated enzymes. To understand better the molecular basis of this phenomenon, we used several approaches such as partial deletions of the adenylate cyclase gene, isolation of peptides of various size, and site-directed mutagenesis experiments. We found that a stretch of 72 amino acid residues overlapping the carboxyl terminus of T25 and the amino terminus of T18 accounts for 90% of the binding energy of adenylate cyclase-CaM complex. The hydrophobic "side" of the helical region situated around Trp242 plays a major role in the interaction of adenylate cyclase with CaM, whereas basic residues that alternate with acidic residues in bacterial enzyme play a much less important role. The amino-terminal half of the catalytic domain of adenylate cyclase contributes only 10% to the binding energy of CaM, whereas the last 130 amino acid residues are not at all involved in binding. However, these segments of adenylate cyclase might affect protein/protein interaction and catalysis by propagating conformational changes to the CaM-binding sequence which is located in the middle of the catalytic domain of bacterial enzyme. PMID:8420945

  11. Tariff charges for electric power and energy

    Tariff types and rules of their construction are presented. Present Polish tariffs are described in detail. The components of tariff charges are given together with some proposals of their optimization. 15 refs, 3 figs, 1 tab

  12. Dynamical charge fluctuation at FAIR energy

    The Compressed Baryonic Matter (CBM) experiment to be held at the Facility for antiproton and ion research (FAIR) is being designed to investigate the baryonic matter under extreme thermodynamic conditions. The hot and dense matter produced in this experiment will be rich in baryon number. It would be worthwhile to examine how the signatures proposed for identifying and characterizing a baryon free QGP like state behave in a baryon rich environment. Event-by-event fluctuation of net electrical charge and/or baryon number is one such indicator of the formation of the QGP, used and tested in RHIC and LHC heavy-ion experiments. One starts by defining the net charge Q = (N+ - N-) and the total charge Nch = (N+ + N-) where the quantities N+ and N- are respectively, the multiplicities of positively and negatively charged particles

  13. Electric Charge as a Form of Imaginary Energy

    Tianxi Zhang

    2008-04-01

    Full Text Available Electric charge is considered as a form of imaginary energy. With this consideration, the energy of an electrically charged particle is a complex number. The real part is proportional to the mass, while the imaginary part is proportional to the electric charge. The energy of an antiparticle is given by conjugating the energy of its corresponding particle. Newton's law of gravity and Coulomb's law of electric force are classically unified into a single expression of the interaction between the complex energies of two electrically charged particles. Interaction between real energies (or masses is the gravitational force. Interaction between imaginary energies (or electric charges is the electromagnetic force. Since radiation is also a form of real energy, there are another two types of interactions between real energies: the mass-radiation interaction and the radiation-radiation interaction. Calculating the work done by the mass-radiation interaction on a photon, we can derive the Einsteinian gravitational redshift. Calculating the work done by the radiation-radiation interaction on a photon, we can obtain a radiation redshift. This study suggests the electric charge as a form of imaginary energy, so that classically unifies the gravitational and electric forces and derives the Einsteinian gravitational redshift.

  14. Research on Battery Charging-Discharging in New Energy Systems

    Che Yanbo; Zhou Yan; Sun Yue; Hu Bo

    2013-01-01

    As an energy storage component, the battery plays increasingly important role in new energy industry. Charging and discharging system is the vital part of the application of the battery, but the charge and discharge are always designed separately and carried by different part in the traditional application. Additionally, most battery discharge mode and method are always simplified which cannot ensure to meet the demand of power utilization. In the actual energy storage system, the design of t...

  15. Phantom Energy Accretion by a Stringy Charged Black Hole

    M.Sharif; G.Abbas

    2012-01-01

    We investigate the dynamical behavior of phantom energy near a stringy magnetically charged black hole. For this purpose, we derive equations of motion for steady-state spherically symmetric Row of phantom energy onto the stringy magnetically charged black hole. It is found that phantom energy accreting onto a black hole decreases its mass. Further, the location of the critical points of accretion is explored, which yields a mass to charge ratio. This ratio implies that accretion process cannot transform a black hole into an extremal black hole or a naked singularity, hence cosmic censorship hypothesis remains valid here.%We investigate the dynamical behavior of phantom energy near a stringy magnetically charged black hole.For this purpose,we derive equations of motion for steady-state spherically symmetric flow of phantom energy onto the stringy magnetically charged black hole.It is found that phantom energy accreting onto a black hole decreases its mass.Further,the location of the critical points of accretion is explored,which yields a mass to charge ratio.This ratio implies that accretion process cannot transform a black hole into an extremal black hole or a naked singularity,hence cosmic censorship hypothesis remains valid here.

  16. Charge transfer energies of tetraphenyl-porphyrin-fullerene dyads

    Zope, Rajendra; Olguin, Marco; Baruah, Tunna

    2011-03-01

    Porphyrin-fullerene dyads are extensively studied for their photoinduced charge transfer properties. They form a donor-acceptor pair where the fullerene is the acceptor. Accurate theoretical estimate of the charge transfer energies in such systems has proven to be a challenge. In this study we examine the charge transfer energetics for such dyads using our recently developed density functional based excited state method which can yield reliable estimates of charge transfer energetics. In this study the effect of varying both the donor and acceptor components are studied by changing the tetra-phenyl-porphyrin (TPP) to Zn-TPP. Similarly the acceptor component is changed from C60 to C70. The structures were optimized using DFT-D3 theory at the all-electron level. Among the donor-acceptor pairs studied, we find that the ZnTPP-C60 has the lowest charge transfer energy (1.69 eV) and the TPP-C70 (2.13 eV) has the highest charge transfer energy. Supported by the Division of Chemical Sciences, Geosciences and Biosciences, Office of Basic Energy Sciences of the US Department of Energy through grant DE-SC0002168.

  17. Energy Charge, Redox State, and Metabolite Turnover in Single Human Hepatocytes Revealed by Capillary Microsampling Mass Spectrometry.

    Zhang, Linwen; Vertes, Akos

    2015-10-20

    Metabolic analysis of single cells to uncover cellular heterogeneity and metabolic noise is limited by the available tools. In this study, we demonstrate the utility of capillary microsampling electrospray ionization mass spectrometry with ion mobility separation for nontargeted analysis of single cells. On the basis of accurate mass measurements and collision cross-section determination, a large number of chemical species, 22 metabolites and 54 lipids, were identified. To assess the cellular response to metabolic modulators, the adenylate energy charge (AEC) levels for control and rotenone treated cells were evaluated. A significant reduction in the AEC values was observed for rotenone treated cells. For the cells under oxidative stress, the mean value for the [reduced glutathione (GSH)]/[oxidized glutathione (GSSG)] ratio was significantly decreased, whereas the distribution of the [uridine diphosphate N-acetylhexosamine (UDP-HexNAc)]/[uridine diphosphate hexose (UDP-hexose)] ratio exhibited dramatic tailing to higher values. Lipid turnover rates were studied by pulse-chase experiments at the single cell level. PMID:26398405

  18. Energy mechanism of charges analyzed in real current environment

    Ianconescu, R; Ianconescu, Reuven

    2003-01-01

    We analyze in this work the energy transfer process of accelerated charges, the mass fluctuations accompanying this process, and their inertial properties. Based on a previous work, we use here the dipole antenna, which is a very convenient framework for such analysis, for analyzing those characteristics. We show that the radiation process can be viewed by two energy transfer processes: one from the energy source to the charges and the second from the charges into the surrounding space. Those processes, not being in phase, result in mass fluctuations. The same principle is true during absorption. We show that in a transient period between absorption and radiation the dipole antenna gains mass according to the amount of absorbed energy and loses this mass as radiated energy. We rigorously prove that the gain of mass, resulting from electrical interaction has inertial properties in the sense of Newton's third low. We arrive to this result by modeling the reacting spacetime region by an electric dipole.

  19. Research on Battery Charging-Discharging in New Energy Systems

    Che Yanbo

    2013-07-01

    Full Text Available As an energy storage component, the battery plays increasingly important role in new energy industry. Charging and discharging system is the vital part of the application of the battery, but the charge and discharge are always designed separately and carried by different part in the traditional application. Additionally, most battery discharge mode and method are always simplified which cannot ensure to meet the demand of power utilization. In the actual energy storage system, the design of the energy converter, which make the power storage and supply as a whole and the design of the charge and discharge method, will play an important role in efficient utilization of the battery system. As a part of the new energy system, the study makes battery and the charging and discharging system as a whole to store energy, which can store and release electric energy high efficiently according to the system state and control the bidirectional flow of energy precisely. Using TMS320F2812 as the control core, the system which integrates charging and discharging with battery monitoring can achieve the bidirectional Buck/Boost power control. It can achieve three-stage charging and selective discharging of the battery. Due to the influence of the diode reverse recovery time, current oscillation will appear. In order to eliminate the oscillation, we can set the circuit to work in critical conduction mode. The experimental result shows that the system can achieve the charging and discharging control of lead-acid battery and increase the battery life time further.

  20. Charge and Energy Dependences of Ionization and Transfer for Helium in Collisions with Fast Charged Projectiles

    FU Hong-Bin; WANG Bao-Hong; DING Bao-Wei; LIU Zhao-Yuan

    2009-01-01

    The classical method within the independent electron model is employed to investigate (i) charge dependences of single and double ionization for helium by various charged ions Aq+ (q = 1 - 8) at impact energies of 0.64 and 1.44 MeV/u, respectively, (ii) energy dependences of transfer ionization for helium by 0.5-3 MeV/u A8,9+ ions impact. The Lenz-Jensen model of the atom is applied instead of the Bohr model of the atom, and the impact-parameter dependences are also introduced into the calculations. Satisfactory agreement is found between theoretical and experimental data.

  1. 10 CFR 904.6 - Charge for capacity and firm energy.

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Charge for capacity and firm energy. 904.6 Section 904.6 Energy DEPARTMENT OF ENERGY GENERAL REGULATIONS FOR THE CHARGES FOR THE SALE OF POWER FROM THE BOULDER CANYON PROJECT Power Marketing § 904.6 Charge for capacity and firm energy. The charge for Capacity...

  2. Charging electric cars from solar energy

    Liang, Xusheng; Tanyi, Elvis; Zou, Xin

    2016-01-01

    Before vehicles were heavily relied on coal, fossil fuels and wind for power.  Now, they are rapidly being replaced by electric vehicles and or plug-in hybrid electric cars. But these electric cars are still faced with the problem of energy availability because they rely on energy from biomass, hydro power and wind turbines for power generation. The abundance of solar radiation and its use as solar energy as a power source in driving these rapidly increasing electric cars is not only an impor...

  3. Quasilocal Energy for Static Charged Black Holes in String Theory

    WANG Shi-Liang; JING Ji-Liang; WANG Yong-Jiu

    2001-01-01

    The Brown-York quasilocal energies of some static charged dilaton black holes are calculated, and then the validity of Martinez's conjecture is explored in string theory. It is shown that the energy is positive and monotonically decreases to the ADM mass at spatial infinity, and the conjecture that the Brown-York quasilocal energy at the outer horizon of black hole reduces to twice of its irreducible mass is still applicable for the static charged black holes in string theory. The result is different from Bose-Naing's one.``

  4. Thermal energy and charge currents in multi-terminal nanorings

    Kramer, Tobias; Kreisbeck, Christoph; Riha, Christian; Chiatti, Olivio; Buchholz, Sven S.; Wieck, Andreas D.; Reuter, Dirk; Fischer, Saskia F.

    2016-06-01

    We study in experiment and theory thermal energy and charge transfer close to the quantum limit in a ballistic nanodevice, consisting of multiply connected one-dimensional electron waveguides. The fabricated device is based on an AlGaAs/GaAs heterostructure and is covered by a global top-gate to steer the thermal energy and charge transfer in the presence of a temperature gradient, which is established by a heating current. The estimate of the heat transfer by means of thermal noise measurements shows the device acting as a switch for charge and thermal energy transfer. The wave-packet simulations are based on the multi-terminal Landauer-Büttiker approach and confirm the experimental finding of a mode-dependent redistribution of the thermal energy current, if a scatterer breaks the device symmetry.

  5. Pituitary adenylate cyclase activating polypeptide and migraine

    Zagami, Alessandro S; Edvinsson, Lars; Goadsby, Peter J

    2014-01-01

    Pituitary adenylate cyclase activating peptide (PACAP) is found in human trigeminocervical complex and can trigger migraine. PACAP levels were measured using a sensitive radioimmunoassay. Stimulation of the superior sagittal sinus (SSS) in cat elevated PACAP levels in cranial blood. Patients with...... moderate or severe migraine headache had elevated PACAP in the external jugular vein during headache (n = 15), that was reduced 1 h after treatment with sumatriptan 6 mg (n = 11), and further reduced interictally (n = 9). The data suggest PACAP, or its receptors, are a promising target for migraine...

  6. Inorganic electret with enhanced charge stability for energy harvesting

    Wang, Fei; Hansen, Ole

    We report a new surface treatment of inorganic electret materials which enhances the charge stability. Coating the surfaces with 1H, 1H, 2H, 2H - perfluorodecyltrichlorosilane (FDTS) makes the electret surface more hydrophobic which improves the surface charge stability under high humidity condit...... conditions. Thermal tests show that the thermal stability of charge in the inorganic electrets is also much better than that of polymer materials such as CYTOP. A demonstrator device with SiO2 electrets shows promising results for energy harvesting applications....

  7. Equilibrium charge state distributions of high energy heavy ions

    Equilibrium charge state fractions have been measured for N, O, Ne, S, Ar and Kr ions at 1.04 MeV/nucleon after passing through various stripping materials. Further data were obtained at higher energy for S ions (4.12 MeV/nucleon) and Ar ions (4.12 and 9.6 MeV/nucleon). The mean charge fractions can be fitted to universal curves for both solid and gaseous strippers. Measurements of the equilibrium fraction of krypton ions at 1.04 MeV/nucleon passing through heavy vapours have shown that a higher average charge state is obtained than for lighter gaseous strippers. (Auth.)

  8. Charge-pickup of 238U at relativistic energies

    Cross sections for the charge-pickup of 238U projectiles were measured at E/A=600 and 1000 MeV for seven different targets (Be, C, Al, Cu, In, Au and U). Events with two fission fragments with a sum charge of 93 in the exit channel were selected. Due to the significant excitation energy, the dominant part of produced Np nuclei fission instead of decaying to the ground state by evaporation. The observed cross sections can be well reproduced by intranuclear-cascade-plus-evaporation calculations and, therefore, confirm recent results that no exotic processes are needed to explain charge-pickup processes. (orig.)

  9. Rapid Charging of Thermal Energy Storage Materials through Plasmonic Heating

    Zhongyong Wang; Peng Tao; Yang Liu; Hao Xu; Qinxian Ye; Hang Hu; Chengyi Song; Zhaoping Chen; Wen Shang; Tao Deng

    2014-01-01

    Direct collection, conversion and storage of solar radiation as thermal energy are crucial to the efficient utilization of renewable solar energy and the reduction of global carbon footprint. This work reports a facile approach for rapid and efficient charging of thermal energy storage materials by the instant and intense photothermal effect of uniformly distributed plasmonic nanoparticles. Upon illumination with both green laser light and sunlight, the prepared plasmonic nanocomposites with ...

  10. Energy dissipation of highly charged ions interacting with solid surfaces

    Motivated by the incomplete scientific description of the relaxation of highly charged ions in front of solid surfaces and their energy balance, this thesis describes an advanced complementary study of determining deposited fractions and re-emitted fractions of the potential energy of highly charged ions. On one side, a calorimetric measurement setup is used to determine the retained potential energy and on the other side, energy resolved electron spectroscopy is used for measuring the reemitted energy due to secondary electron emission. In order to study the mechanism of energy retention in detail, materials with different electronic structures are investigated: Cu, n-Si, p-Si and SiO2. In the case of calorimetry, a linear relationship between the deposited potential energy and the inner potential energy of the ions was determined. The total potential energy which stays in the solid remains almost constant at about (80 ± 10) %. Comparing the results of the Cu, n-Si and p-Si targets, no significant difference could be shown. Therefore we conclude that the difference in energy deposition between copper, n-doped Si and p-doped Si is below 10 %, which is significantly lower than using SiO2 targets. For this purpose, electron spectroscopy provides a complementary result. For Cu and Si surfaces, an almost linear increase of the re-emitted energy with increasing potential energy of the ion up to Ar7+ was also observed. The ratio of the re-emitted energy is about (10 ± 5) % of the total potential energy of the incoming ion, almost independent of the ion charge state. In contrast, an almost vanishing electron emission was observed for SiO2 and for charge states below q=7. For Ar8+ and Ar9+, the electron emission increased due to the contribution of the projectile LMM Auger electrons and the re-emitted energy amounts up to 20 % for Cu and Si and around 10 % for SiO2. These results are in good agreement with the calorimetric values. In addition, the experimental results

  11. Mass and Charge Distribution in Low-Energy Fission

    The mass and charge distributions for thermal-neutron fission of U235 are discussed in considerable detail and compared with the corresponding distributions in other low-energy fission processes. Points discussed in connection with the mass distributions for binary fission include the positions of the peaks, valley and fine structure in a mass yield curve with respect to filled nuclear shells and the changes in the positions that occur with changing fissioning nucleus and excitation energy. The mass distribution from ternary fission is discussed also. For both binary and ternary fission comments are made concerning the mass distributions of primary fragments (before neutron evaporation) and of fission products (after neutron evaporation). Charge distribution is discussed in terms of charge dispersion among fission products with the same mass number and the variation with mass number of Zp, the ''most probable charge'' (non-integral) for a given mass number. Although direct information about charge distribution is limited to fission products, estimates are presented of charge distribution for primary fission fragments. Knowledge and estimates of mass and charge distribution for a fission process allow estimation of primary yields of all fission products or fragments. Although many estimated primary yields are quite uncertain mainly because of lack of knowledge of charge distribution, especially for fission products formed in low yield; some estimates of primary yields are presented to illustrate the need for and possible practicality of further experimentation. Fission processes other than thermal-neutron fission of U235 that are discussed include thermal-neutron fission of U233 and Pu239, spontaneous fission of Pu240 and Cf252, 14-MeV neutron fission of U235 and U238, 11-MeV proton fission of Ra226 and 22-MeV deuteron fission of Bi209. (author)

  12. Fast Charging and Smart Charging Tests for Electric Vehicles Batteries Using Renewable Energy

    Forero Camacho Oscar Mauricio

    2016-01-01

    Full Text Available Electric Vehicles (EV technologies are still relatively new and under strong development. Although some standardized solutions are being promoted and becoming a new trend, there is an outstanding need for common platforms and sharing of knowledge and core technologies. This paper presents the development of a test platform, including three Li-ion batteries designed for EV applications, and three associated bi-directional power converters, for testing impacts on different advanced loadings of EV batteries. Different charging algorithms/profiles have been tested, including constant current and power, and forced and pulsed power. The aim of the tests has been to study the impact of smart charging and fast charging on the power system, on the battery state of health and degradation, and to find out the limitations of the batteries for a Smart Grid. The paper outlines the advantages and disadvantages of both tests in terms of regulation of the aggregated local power, power capacity and the power exchange with the grid. The smart charging tests performed have demonstrated that even with a simple control algorithm, without any forecasting, it is possible to provide the required charging and at the same time the power system services, reducing the peak power and the energy losses in the power connection line of the power exchange with the national grid.

  13. Medical radiation dosimetry theory of charged particle collision energy loss

    McParland, Brian J

    2014-01-01

    Accurate radiation dosimetry is a requirement of radiation oncology, diagnostic radiology and nuclear medicine. It is necessary so as to satisfy the needs of patient safety, therapeutic and diagnostic optimisation, and retrospective epidemiological studies of the biological effects resulting from low absorbed doses of ionising radiation. The radiation absorbed dose received by the patient is the ultimate consequence of the transfer of kinetic energy through collisions between energetic charged particles and atoms of the tissue being traversed. Thus, the ability of the medical physicist to both measure and calculate accurately patient dosimetry demands a deep understanding of the physics of charged particle interactions with matter. Interestingly, the physics of charged particle energy loss has an almost exclusively theoretical basis, thus necessitating an advanced theoretical understanding of the subject in order to apply it appropriately to the clinical regime. ​ Each year, about one-third of the worl...

  14. INTRAMOLECULAR CHARGE AND ENERGY TRANSFER IN MULTICHROMOPHORIC AROMATIC SYSTEMS

    Edward C. Lim

    2008-09-09

    A concerted experimental and computational study of energy transfer in nucleic acid bases and charge transfer in dialkylaminobenzonitriles, and related electron donor-acceptor molecules, indicate that the ultrafast photoprocesses occur through three-state conical interactions involving an intermediate state of biradical character.

  15. Acceleration of low energy charged particles by gravitational waves

    Voyatzis, G.; Vlahos, L.; Ichtiaroglou, S.; Papadopoulos, D.

    2005-01-01

    The acceleration of charged particles in the presence of a magnetic field and gravitational waves is under consideration. It is shown that the weak gravitational waves can cause the acceleration of low energy particles under appropriate conditions. Such conditions may be satisfied close to the source of the gravitational waves if the magnetized plasma is in a turbulent state.

  16. Renewable Energy for Electric Vehicles: Price Based Charging Coordination

    Richstein, J.C.; Schuller, A.; Dinther, C.; Ketter, W.; Weinhardt, C.

    2012-01-01

    In this paper we investigate the charging coordination of battery electric vehicles (BEV) with respect to the availability of intermittent renewable energy generation considering individual real world driving profiles in a deterministic simulation based analysis, mapping a part of the German power s

  17. Charge-state-dependent energy loss of slow ions. I. Experimental results on the transmission of highly charged ions

    Wilhelm, Richard A.; Gruber, Elisabeth; Smejkal, Valerie; Facsko, Stefan; Aumayr, Friedrich

    2016-05-01

    We report on energy loss measurements of slow (v ≪v0 ), highly charged (Q >10 ) ions upon transmission through a 1-nm-thick carbon nanomembrane. We emphasize here the scaling of the energy loss with the velocity and charge exchange or loss. We show that a weak linear velocity dependence exists, whereas charge exchange dominates the kinetic energy loss, especially in the case of a large charge capture. A universal scaling of the energy loss with the charge exchange and velocity is found and discussed in this paper. A model for charge-state-dependent energy loss for slow ions is presented in paper II in this series [R. A. Wilhelm and W. Möller, Phys. Rev. A 93, 052709 (2016), 10.1103/PhysRevA.93.052709].

  18. Laser focusing of high-energy charged-particle beams

    It is shown that laser focusing of high-energy charged-particle beams using the inverse Cherenkov effect is well suited for applications with large linear colliders. Very high gradient (>0.5 MG/cm) lenses result that can be added sequentially without AG cancellation. These lenses are swell understood, have small geometric aberrations, and offer the possibility of correlating phase and energy aberrations to produce an achromatic final focus

  19. Metabolic energy is required in human platelets at any stage during optical aggregation and secretion

    Akkerman, Jan Willem N.; Verhoeven, A J M; Mommersteeg, M.E.

    1984-01-01

    The relationship between metabolic energy and platelet aggregation and secretion was investigated by sudden exhaustion of the cell energy content after these platelet responses had been initiated. In normal platelets, optical aggregation was at any stage susceptible to energy exhaustion, whereas single platelet disappearance and secretion were hardly affected. Prelowering the platelet energy content, while preserving the adenylate energy charge, made both optical aggregation and the secretion...

  20. Structural studies of Schistosoma mansoni adenylate kinases

    Marques, I.A. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil); Pereira, H.M.; Garrat, R.C. [Universidade de Sao Paulo (USP-SC), Sao Carlos, SP (Brazil)

    2012-07-01

    Full text: Parasitic diseases are a major cause of death in developing countries, however receive little or no attention from pharmaceutical companies for the development of novel therapies. In this respect, the Center for Structural Molecular Biology (CBME) of the Institute of Physics of Sao Carlos (IFSC / USP) has developed expertise in all stages of the development of active compounds against target enzymes from parasitic diseases. The present work focuses on the adenylate kinase enzymes (ADK's) from Schistosoma mansoni. These enzymes are widely distributed and catalyze the reaction of phosphoryl exchange between nucleotides in the reaction 2ADP to ATP + AMP, which is critical for the cells life cycle. Due to the particular property of the reaction catalyzed, the ADK's are recognized as reporters of the cells energetic state, translating small changes in the balance between ATP and ADP into a large change in concentration of AMP. The genome of S. mansoni was recently sequenced by the Sanger Center in England. On performing searches for genes encoding adenylate kinases we found two such genes. The corresponding gene products were named ADK1 (197 residues) and ADK2 (239 residues), and the two sequences share only 28 percent identity. Both have been cloned into the pET-28a(+)vector, expressed in E. coli and purified. Preliminary tests of activity have been performed only for ADK1 showing it to be catalytically active. Crystallization trials were performed for both proteins and thus far, crystals of ADK1 have been obtained which diffract to 2.05 at the LNLS beamline MX2 and the structure solved by molecular replacement. Understanding, at the atomic level, the function of these enzymes may help in the development of specific inhibitors and may provide tools for developing diagnostic tests for schistosomiasis. (author)

  1. Charge, mass and energy measured in the Plastic Ball

    In relativistic nuclear collisions the multiplicity of charged particles reflects the violence of the reaction and, presumably, the impact parameter. Furthermore, the total transverse energy in a collision might be a signature of compression. Both quantities are global features that can be measured in the Plastic Ball. The total mass in an event in light charge fragments can be detected (with assumptions made in certain kinematic regions) through particle identification. In addition, the neutron detection efficiency is quite high because of the large thickness of the plastic scintillator in the Plastic Ball. Here the authors present several global quantities for the reaction of 400 MeV/nucleon Nb + Nb

  2. Interaction of low-energy highly charged ions with matter

    The thesis presented herein deals with experimental studies of the interaction between highly charged ions and neutral matter at low collision energies. The energy range investigated is of great interest for the understanding of both charge exchange reactions between ions comprising the solar wind and various astrophysical gases, as well as the creation of near-surface nanostructures. Over the course of this thesis an experimental setup was constructed, capable of reducing the kinetic energy of incoming ions by two orders of magnitude and finally focussing the decelerated ion beam onto a solid or gaseous target. A coincidence method was employed for the simultaneous detection of photons emitted during the charge exchange process together with the corresponding projectile ions. In this manner, it was possible to separate reaction channels, whose superposition presumably propagated large uncertainties and systematic errors in previous measurements. This work has unveiled unexpectedly strong contributions of slow radiative decay channels and clear evidence of previously only postulated decay processes in charge exchange-induced X-ray spectra. (orig.)

  3. Restrictions on charged Higgs bosons from low-energy data

    Charged Higgs bosons, which are present if the minimal one-doublet Higgs sector of the Standard Model is extended to include two (or more) Higgs doublets, may contribute to a variety of low-energy processes via H± exchange in internal loops. Consistency with data places overall restrictions on the mass and coupling parameter. Results are presented from a combined analysis of these contributions which take the large freedom in the allowed ranges of all the parameters into account

  4. Models for Energy and Charge Transport and Storage in Biomolecules

    Mingaleev, S. F.; Christiansen, P. L.; Gaididei, Yu. B.; M. Johansson; Rasmussen, K.Ø.

    1999-01-01

    Two models for energy and charge transport and storage in biomolecules are considered. A model based on the discrete nonlinear Schrodinger equation with long-range dispersive interactions (LRI's) between base pairs of DNA is offered for the description of nonlinear dynamics of the DNA molecule. We show that LRI's are responsible for the existence of an interval of bistability where two stable stationary states, a narrow, pinned state and a broad, mobile state, coexist at each value of the tot...

  5. Adenylate kinase from Streptococcus pneumoniae is essential for growth through its catalytic activity

    Trung Thanh Thach

    2014-01-01

    Full Text Available Streptococcus pneumoniae (pneumococcus infection causes more than 1.6 million deaths worldwide. Pneumococcal growth is a prerequisite for its virulence and requires an appropriate supply of cellular energy. Adenylate kinases constitute a major family of enzymes that regulate cellular ATP levels. Some bacterial adenylate kinases (AdKs are known to be critical for growth, but the physiological effects of AdKs in pneumococci have been poorly understood at the molecular level. Here, by crystallographic and functional studies, we report that the catalytic activity of adenylate kinase from S. pneumoniae (SpAdK serotype 2 D39 is essential for growth. We determined the crystal structure of SpAdK in two conformations: ligand-free open form and closed in complex with a two-substrate mimic inhibitor adenosine pentaphosphate (Ap5A. Crystallographic analysis of SpAdK reveals Arg-89 as a key active site residue. We generated a conditional expression mutant of pneumococcus in which the expression of the adk gene is tightly regulated by fucose. The expression level of adk correlates with growth rate. Expression of the wild-type adk gene in fucose-inducible strains rescued a growth defect, but expression of the Arg-89 mutation did not. SpAdK increased total cellular ATP levels. Furthermore, lack of functional SpAdK caused a growth defect in vivo. Taken together, our results demonstrate that SpAdK is essential for pneumococcal growth in vitro and in vivo.

  6. Energy loss of charged particles colliding with an oscillator

    Makarov, D. N.

    2015-04-01

    Energy loss of fast charged particles colliding with an oscillator is considered in the dipole approximation. In this approximation, the problem is solved exactly and the energy loss of the oscillator from the initial state | m> = |0> is found in the form of the sum of single integrals. It is shown that passing to the limit, the Bethe theory for an atom with small perturbations can be obtained, and in the case of strong fields, the correction to the Bethe theory, analogous to the Bloch correction, can be calculated; in addition, a classical limit coinciding with the Bohr formula is possible.

  7. Instrument to measure energy and charge of low energy interplanetary particles

    Tums, E.; Gloeckler, G.; Cain, J.; Sciambi, R.; Fan, C. Y.

    1974-01-01

    An experiment to measure the charge composition and energy spectra of ultra low energy charged particles in interplanetary space has been developed and launched on the IMP 8 (Explorer 50) satellite on Oct. 26, 1973. The instrument consists of two separate sensors sharing common electronics. One of these sensors uses a thin window gas proportional counter to measure the rate of energy loss and a totally depleted silicon surface barrier detector to measure total energy of incoming particles. The energy range for two dimensional analysis extends from 300 KeV to 2.5 MeV for protons and 60 KeV/nucleon to 25 MeV/nucleon for iron with excellent resolution of individual chemical elements. The other sensor combines electrostatic deflection with total energy measurements in silicon surface barrier detectors to give the ionic charge and kinetic energy of the particle.

  8. Functional Arrays for Light Energy Capture and Charge Separation.

    Flamigni, Lucia

    2016-06-01

    This article draws, with a simplified but rigorous approach, the typical procedure for the design and optimization of functional multicomponent structures for light to chemical energy conversion for two series of multipartite structures based on prototypical chromophores: polypyridyl metal complexes and porphyrinoids. Starting from a photophysical study performed by steady-state and time-resolved spectroscopic methods, the full deactivation dynamics of the light-absorbing chromophore(s) are disclosed. The preferred deactivation step (electron transfer in this case) is then optimized. This can be done by simply operating on the solvent, but also by changing structure/components that can alter electronic and nuclear factors, via continuous feedback with the research groups in charge of the synthesis. With a presentation suitable for a wide audience, it is here discussed how the effective design of functional multicomponent structures for charge separation can be achieved. PMID:27027981

  9. Photoinduced charge and energy transfer in molecular wires.

    Gilbert, Mélina; Albinsson, Bo

    2015-02-21

    Exploring charge and energy transport in donor-bridge-acceptor systems is an important research field which is essential for the fundamental knowledge necessary to develop future applications. These studies help creating valuable knowledge to respond to today's challenges to develop functionalized molecular systems for artificial photosynthesis, photovoltaics or molecular scale electronics. This tutorial review focuses on photo-induced charge/energy transfer in covalently linked donor-bridge-acceptor (D-B-A) systems. Of utmost importance in such systems is to understand how to control signal transmission, i.e. how fast electrons or excitation energy could be transferred between the donor and acceptor and the role played by the bridge (the "molecular wire"). After a brief description of the electron and energy transfer theory, we aim to give a simple yet accurate picture of the complex role played by the bridge to sustain donor-acceptor electronic communication. Special emphasis is put on understanding bridge energetics and conformational dynamics effects on the distance dependence of the donor-acceptor electronic coupling and transfer rates. Several examples of donor-bridge-acceptor systems from the literature are described as a support to the discussion. Finally, porphyrin-based molecular wires are introduced, and the relationship between their electronic structure and photophysical properties is outlined. In strongly conjugated porphyrin systems, limitations of the existing electron transfer theory to interpret the distance dependence of the transfer rates are also discussed. PMID:25212903

  10. Charge transport in columnar stacked triphenylenes: Effects of conformational fluctuations on charge transfer integrals and site energies

    Senthilkumar, K.; Grozema, F.C.; Bickelhaupt, F.M.; Siebbeles, L.D.A.

    2003-01-01

    Values of charge transfer integrals, spatial overlap integrals and site energies involved in transport of positive charges along columnar stacked triphenylene derivatives are provided. These parameters were calculated directly as the matrix elements of the Kohn–Sham Hamiltonian, defined in terms of

  11. Charged Pion Energy Reconstruction in the ATLAS Barrel Calorimeter

    Bosman, M; Nessi, Marzio

    2000-01-01

    The intrinsic performance of the ATLAS barrel and extended barrelcalorimeters for the measurement of charged pions is presented. Pion energyscans (E = 20, 50, 200, 400 and 1000 GeV) at two pseudo-rapidity points ($\\eta$= 0.3 and 1.3) and pseudorapidity scans ($-0.2 < \\eta < 1.8$) with pions ofconstant transverse energy ($E_T = 20$ and 50 GeV) are analysed. A simpleapproach, that accounts in first order for non-compensation and dead materialeffects, is used for the pion energy reconstruction. The intrinsic performancesof the calorimeter are studied: resolution, linearity, effect of dead material,tails in the energy distribution. The effect of electronic noise, cell energycuts and restricted cone size are investigated.

  12. A large solid angle detector for medium energy charged particles

    A charged particle detector with 0.7 sr solid angular acceptance has been built, principally to detect protons in the energy range 25-150 MeV in experiments with tagged photon beams. The detector consists of a three element ΔE1-ΔE2-E plastic scintillator telescope. Position information is obtained from the time difference between signals from the two ends of each scintillator. The design of the detector and tests of its performance are described. An energy resolution of 2.8 MeV fwhm at 60 MeV proton energy, and a two-dimensional position resolution of 24 mm x 41 mm fwhm has been obtained. Successful operation in the tagged photon environment is demonstrated. (orig.)

  13. Models for Energy and Charge Transport, and Storage in Biomolecules

    Mingaleev, S F; Gaididei, Yu B; Johansson, M; Rasmussen, K O; Mingaleev, Serge F.; Christiansen, Peter L.; Gaididei, Yuri B.; Johansson, Magnus; Rasmussen, Kim O.

    1999-01-01

    Two models for energy and charge transport and storage in biomolecules are considered. A model based on the discrete nonlinear Schrodinger equation with long-range dispersive interactions (LRI's) between base pairs of DNA is offered for the description of nonlinear dynamics of the DNA molecule. We show that LRI's are responsible for the existence of an interval of bistability where two stable stationary states, a narrow, pinned state and a broad, mobile state, coexist at each value of the total energy. The possibility of controlled switching between pinned and mobile states is demonstrated. The mechanism could be important for controlling energy storage and transport in DNA molecules. Another model is offered for the description of nonlinear excitations in proteins and other anharmonic biomolecules. We show that in the highly anharmonic systems a bound state of Davydov and Boussinesq solitons can exist.

  14. Glucagon and adenylate cyclase: binding studies and requirements for activation.

    Levey, G S; Fletcher, M A; Klein, I

    1975-01-01

    Solubilization of myocardial adenylate cyclase abolished responsiveness to glucagon and catecholamines, two of the hormones which activate the membrane-bound enzyme. Adenylate cyclase freed of detergent by DEAE-cellulose chromatography continues to remain unresponsive to hormone stimulation. However, adding purified bovine brain phospholipids--phosphotidylserine and monophosphatidylinositol--restored responsiveness to glucagon and catecholamines, respectively. 125-i-glucagon binding appeared to be independent of phospholipid, since equal binding was observed in the presence or absence of detergent and in the presence or absence of phospholipids. Chromatography of the solubilized preparation on Sephadex G-100 WAS CHARACTERIZED BY 125-I-glucagon binding and fluoride-stimulatable adenylate cyclase activity appearing in the fractions consistent with the void volume, suggesting a molecular weight greater than 100,000 for the receptor-adenylate cyclase complex. Prior incubation of the binding peak with 125-I-glucagon and rechromatography of the bound glucagon on Sephadex G-100 shifted its elution to a later fraction consistent with a smaller-molecular-weight peak. The molecular weight of this material was 24,000 to 28,000, as determined by SDS polyacrylamide gel electrophoresis. The latter findings are consistent with a dissociable receptor site for glucagon on myocardial adenylate cyclase. PMID:165684

  15. Charged Pion Energy Reconstruction in the ATLAS Barrel Calorimeter

    Bosman, Martine; Nessi, Marzio

    1999-01-01

    Intrinsic performance of the ATLAS calorimeters in the barrel region with respect to charged pions was studied. For this the following simulated data were used: pion energy scans ($E = 20, 50, 200, 400$ and $1000$ GeV) at two pseudo-rapidity points ($eta = 0.3$ and $1.3$) and pseudo-rapidity scans ($-0.2 < eta < 1.8$) with pions of constant transverse energy ($E_T = 20$ and $50$ GeV). For pion energy reconstruction the benchmark approach was used. Performance was estimated for cases, when energy and rapidity dependent and independent calibration parameters were applied. The best results were obtained with energy and rapidity dependent parameters. Studies done for pions enabled optimization of the cone size and of the cut to obtain the best energy resolution. Energy dependence of the resolution can be parameterized as: $(50pm4)%/sqrt{E} oplus (3.4pm0.3)% oplus 1.0/E$ at $eta = 0.3$ and $(68pm8)%/sqrt{E} oplus (3.0pm0.7)% oplus 1.5/E$ at $eta = 1.3$. Larger constant term at $eta=0.3$ can be explained by l...

  16. On the energy losses of fast charged particles

    Matveev, V. I.; Makarov, D. N.; Gusarevich, E. S.

    2010-09-01

    The energy losses of fast charged particles colliding with atoms have been considered in the eikonal approximation. It has been shown that the nonperturbative contribution to the effective stopping from the region of the intermediate impact parameters (comparable with the characteristic sizes of the electron shells of the target) not only can be significant as compared to shell corrections to the Bethe-Bloch formula (usually considered in the first order of perturbation theory), but also can provide significant (up to 50%) corrections to this formula.

  17. Charged particle detectors with active detector surface for partial energy deposition of the charged particles and related methods

    Gerts, David W; Bean, Robert S; Metcalf, Richard R

    2013-02-19

    A radiation detector is disclosed. The radiation detector comprises an active detector surface configured to generate charge carriers in response to charged particles associated with incident radiation. The active detector surface is further configured with a sufficient thickness for a partial energy deposition of the charged particles to occur and permit the charged particles to pass through the active detector surface. The radiation detector further comprises a plurality of voltage leads coupled to the active detector surface. The plurality of voltage leads is configured to couple to a voltage source to generate a voltage drop across the active detector surface and to separate the charge carriers into a plurality of electrons and holes for detection. The active detector surface may comprise one or more graphene layers. Timing data between active detector surfaces may be used to determine energy of the incident radiation. Other apparatuses and methods are disclosed herein.

  18. Charge collection efficiency of GaAs detectors studied with low-energy heavy charged particles

    Bates, R; Linhart, V; O'Shea, V; Pospísil, S; Raine, C; Smith, K; Sinor, M; Wilhelm, I

    1999-01-01

    Epitaxially grown GaAs layers have recently been produced with sufficient thickness and low enough free carrier concentration to permit their use as radiation detectors. Initial tests have shown that the epi-material behaves as a classical semiconductor as the depletion behaviour follows the square root dependency on the applied bias. This article presents the results of measurements of the growth of the active depletion depth with increasing bias using low-energy protons and alpha particles as probes for various depths and their comparison to values extrapolated from capacitance measurements. From the proton and alpha particle spectroscopic measurements, an active depth of detector material that collects 100% of the charge generated inside it was determined. The consistency of these results with independent capacitance measurements supports the idea that the GaAs epi-material behaves as a classical semiconductor. (author)

  19. Modeling energy and charge transports in pi-conjugated systems

    Shin, Yongwoo

    Carbon based pi-conjugated materials, such as conducting polymers, fullerene, carbon nanotubes, graphene, and conjugated dendrimers have attracted wide scientific attentions in the past three decades. This work presents the first unified model Hamiltonian that can accurately capture the low-energy excitations among all these pi-conjugated systems, even with the presence of defects and heterogeneous sites. Two transferable physical parameters are incorporated into the Su-Schrieffer-Heeger Hamiltonian to model conducting polymers beyond polyacetylene: the parameter gamma scales the electronphonon coupling strength in aromatic rings and the other parameter epsilon specifies the heterogeneous core charges. This generic Hamiltonian predicts the fundamental band gaps of polythiophene, polypyrrole, polyfuran, poly-(p-phenylene), poly-(p-phenylene vinylene), polyacenes, fullerene, carbon nanotubes, graphene, and graphene nanoribbons with an accuracy exceeding time-dependent density functional theory. Its computational costs for moderate-length polymer chains are more than eight orders of magnitude lower than first-principles approaches. The charge and energy transports along -conjugated backbones can be modeled on the adiabatic potential energy surface. The adiabatic minimum-energy path of a self-trapped topological soliton is computed for trans-polyacetylene. The frequently cited activation barrier via a ridge shift of the hyper-tangent order parameter overestimates its true value by 14 orders of magnitude. Self-trapped solitons migrate along the Goldstone mode direction with continuously adjusted amplitudes so that a small-width soliton expands and a large-width soliton shrinks when they move uphill. A soliton with the critical width may migrate without any amplitude modifications. In an open chain as solitons move from the chain center toward a chain edge, the minimum-energy path first follows a tilted washboard. Such a generic constrained Goldstone mode relaxation

  20. Charge Calibration of the ANTARES high energy neutrino telescope

    Baret, Bruny

    2009-01-01

    ANTARES is a deep-sea, large volume Mediterranean neutrino telescope installed off the Coast of Toulon, France. It is taking data in its complete configuration since May 2008 with nearly 900 photomultipliers installed on 12 lines. It is today the largest high energy neutrino telescope of the northern hemisphere. The charge calibration and threshold tuning of the photomultipliers and their associated front-end electronics is of primary importance. It indeed enables to translate signal amplitudes into number of photo-electrons which is the relevant information for track and energy reconstruction. It has therefore a strong impact on physics analysis. We will present the performances of the front-end chip, so-called ARS, including the waveform mode of acquisition. The in-laboratory as well as regularly performed in situ calibrations will be presented together with related studies like the time evolution of the gain of photomultipliers

  1. Coulomb charging energy of vacancy-induced states in graphene

    Miranda, V. G.; Dias da Silva, Luis G. G. V.; Lewenkopf, C. H.

    2016-08-01

    Vacancies in graphene have been proposed to give rise to π -like magnetism in carbon materials, a conjecture which has been supported by recent experimental evidence. A key element in this "vacancy magnetism" is the formation of magnetic moments in vacancy-induced electronic states. In this work we compute the charging energy U of a single-vacancy-generated localized state for bulk graphene and graphene ribbons. We use a tight-binding model to calculate the dependency of the charging energy U on the amplitudes of the localized wave function on the graphene lattice sites. We show that for bulk graphene U scales with the system size L as (lnL) -2, confirming the predictions in the literature, based on heuristic arguments. In contrast, we find that for realistic system sizes U is of the order of eV, a value that is orders of magnitude higher than the previously reported estimates. Finally, when edges are considered, we show that U is very sensitive to the vacancy position with respect to the graphene flake boundaries. In the case of armchair nanoribbons, we find a strong enhancement of U in certain vacancy positions as compared to the value for vacancies in bulk graphene.

  2. Suppression of Platelet Aggregation by Bordetella pertussis Adenylate Cyclase Toxin

    Iwaki, Masaaki; Kamachi, Kazunari; Heveker, Nikolaus; Konda, Toshifumi

    1999-01-01

    The effect of Bordetella pertussis adenylate cyclase toxin (ACT) on platelet aggregation was investigated. This cell-invasive adenylate cyclase completely suppressed ADP (10 μM)-induced aggregation of rabbit platelets at 3 μg/ml and strongly suppressed thrombin (0.2 U/ml)-induced aggregation at 10 μg/ml. The suppression was accompanied by marked increase in platelet intracellular cyclic AMP (cAMP) content and was diminished by the anti-ACT monoclonal antibody B7E11. A catalytically inactive p...

  3. Charged Particle, Photon Multiplicity, and Transverse Energy Production in High-Energy Heavy-Ion Collisions

    We review the charged particle and photon multiplicities and transverse energy production in heavy-ion collisions starting from few GeV to TeV energies. The experimental results of pseudorapidity distribution of charged particles and photons at different collision energies and centralities are discussed. We also discuss the hypothesis of limiting fragmentation and expansion dynamics using the Landau hydrodynamics and the underlying physics. Meanwhile, we present the estimation of initial energy density multiplied with formation time as a function of different collision energies and centralities. In the end, the transverse energy per charged particle in connection with the chemical freeze-out criteria is discussed. We invoke various models and phenomenological arguments to interpret and characterize the fireball created in heavy-ion collisions. This review overall provides a scope to understand the heavy-ion collision data and a possible formation of a deconfined phase of partons via the global observables like charged particles, photons, and the transverse energy measurement

  4. The lowest-energy charge-transfer state and its role in charge separation in organic photovoltaics.

    Nan, Guangjun; Zhang, Xu; Lu, Gang

    2016-06-29

    Energy independent, yet higher than 90% internal quantum efficiency (IQE), has been observed in many organic photovoltaics (OPVs). However, its physical origin remains largely unknown and controversial. The hypothesis that the lowest charge-transfer (CT) state may be weakly bound at the interface has been proposed to rationalize the experimental observations. In this paper, we study the nature of the lowest-energy CT (CT1) state, and show conclusively that the CT1 state is localized in typical OPVs. The electronic couplings in the donor and acceptor are found to determine the localization of the CT1 state. We examine the geminate recombination of the CT1 state and estimate its lifetime from first principles. We identify the vibrational modes that contribute to the geminate recombination. Using material parameters determined from first principles and experiments, we carry out kinetic Monte Carlo simulations to examine the charge separation of the localized CT1 state. We find that the localized CT1 state can indeed yield efficient charge separation with IQE higher than 90%. Dynamic disorder and configuration entropy can provide the energetic and entropy driving force for charge separation. Charge separation efficiency depends more sensitively on the dimension and crystallinity of the acceptor parallel to the interface than that normal to the interface. Reorganization energy is found to be the most important material parameter for charge separation, and lowering the reorganization energy of the donor should be pursued in the materials design. PMID:27306609

  5. Nucleon charge-exchange reactions at intermediate energy

    Alford, W.P. [Western Ontario Univ., London, ON (Canada). Dept. of Physics]|[TRIUMF, Vancouver, BC (Canada); Spicer, B.M. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1997-12-31

    An historical review of the development of ideas pertaining to Gamow-Teller giant resonances is given, and a description of the emergence of techniques for the study of charge exchange reactions - particularly the technical advances which yielded the recent volume of new date. The present status of charge exchange reactions is reviewed and assessed. Evidence is presented from the {sup 14}C(p,n) reaction for the dominance of the spin-isospin component of the nucleon-nucleon interaction in intermediate energy reactions. In (p,n) reactions the Gamow-Teller giant resonance dominates the spectra, with higher multipoles contributing. By contrast, in (n,p) reactions in the heavier nuclei, the Gamow-Teller transitions are substantially Pauli-blocked and the spin dipole resonance dominates, with contributions from higher multipoles. Discussions of the multipole decomposition process, used to obtain from the data the contributions of the different multipoles, and the contributions of the multipoles, are given. 226 refs., 19 figs.

  6. Charge transport in columnar stacked triphenylenes: Effects of conformational fluctuations on charge transfer integrals and site energies

    K. Senthilkumar; Grozema, F.C.; Bickelhaupt, F.M.; Siebbeles, L.D.A.

    2003-01-01

    Values of charge transfer integrals, spatial overlap integrals and site energies involved in transport of positive charges along columnar stacked triphenylene derivatives are provided. These parameters were calculated directly as the matrix elements of the Kohn–Sham Hamiltonian, defined in terms of the molecular orbitals on individual triphenylene molecules. This was realized by exploiting the unique feature of the Amsterdam density functional theory program that allows one to use molecular o...

  7. A theoretical description of charge reorganization energies in molecular organic P-type semiconductors.

    Brückner, Charlotte; Engels, Bernd

    2016-06-01

    Charge transport properties of materials composed of small organic molecules are important for numerous optoelectronic applications. A material's ability to transport charges is considerably influenced by the charge reorganization energies of the composing molecules. Hence, predictions about charge-transport properties of organic materials deserve reliable statements about these charge reorganization energies. However, using density functional theory which is mostly used for the predictions, the computed reorganization energies depend strongly on the chosen functional. To gain insight, a benchmark of various density functionals for the accurate calculation of charge reorganization energies is presented. A correlation between the charge reorganization energies and the ionization potentials is found which suggests applying IP-tuning to obtain reliable values for charge reorganization energies. According to benchmark investigations with IP-EOM-CCSD single-point calculations, the tuned functionals provide indeed more reliable charge reorganization energies. Among the standard functionals, ωB97X-D and SOGGA11X yield accurate charge reorganization energies in comparison with IP-EOM-CCSD values. © 2016 Wiley Periodicals, Inc. PMID:27059122

  8. Scaling of the Coulomb Energy Due to Quantum Fluctuations in the Charge on a Quantum Dot

    Molenkamp, L. W; Flensberg, Karsten; Kemerink, M.

    1995-01-01

    The charging energy of a quantum dot is measured through the effect of its potential on the conductance of a second dot. This technique allows a measurement of the scaling of the dot's charging energy with the conductance of the tunnel barriers leading to the dot. We find that the charging energy...... scales quadratically with the reflection probability of the barriers. The observed power law agrees with a recent theory....

  9. Assessment of renewable energy technologies for charging electric vehicles in Canada

    Electric vehicle charging by renewable energy can help reduce greenhouse gas emissions. This paper presents a data-intensive techno-economic model to estimate the cost of charging an electric vehicle with a battery capacity of 16 kW h for an average travel distance of 65 km from small-scale renewable electricity in various jurisdictions in Canada. Six scenarios were developed that encompass scale of operation, charging time, and type of renewable energy system. The costs of charging an electric vehicle from an off-grid wind energy system at a charging time of 8 h is 56.8–58.5 cents/km in Montreal, Quebec, and 58.5–60.0 cents/km in Ottawa, Ontario. However, on integration with a small-scale hydro, the charging costs are 9.4–11.2 cents/km in Montreal, 9.5–11.1 cents/km in Ottawa and 10.2–12.2 cents/km in Vancouver, British Columbia. The results show that electric vehicle charging from small-scale hydro energy integration is cost competitive compared charging from conventional grid electricity in all the chosen jurisdictions. Furthermore, when the electric vehicle charging time decreases from 8 to 4 h, the cost of charging increases by 83% and 11% from wind and hydro energy systems, respectively. - Highlights: • Techno-economic analysis conducted for EV charging from wind and hydro. • EV charging from hydro energy is cost competitive than from wind energy. • GHG mitigation estimated from operation of EV charged from renewable energy. • Sensitivity of key parameters on cost of charging considered

  10. Strong subadditivity, null energy condition and charged black holes

    Using the Hubeny-Rangamani-Takayanagi (HRT) conjectured formula for entanglement entropy in the context of the AdS/CFT correspondence with time-dependent backgrounds, we investigate the relation between the bulk null energy condition (NEC) of the stress-energy tensor with the strong sub-additivity (SSA) property of entanglement entropy in the boundary theory. In a background that interpolates between an AdS to an AdS-Reissner-Nordstrom-type geometry, we find that generically there always exists a critical surface beyond which the violation of NEC would naively occur. However, the extremal area surfaces that determine the entanglement entropy for the boundary theory, can penetrate into this forbidden region only for certain choices for the mass and the charge functions in the background. This penetration is then perceived as the violation of SSA in the boundary theory. We also find that this happens only when the critical surface lies above the apparent horizon, but not otherwise. We conjecture that SSA, which is thus non-trivially related to NEC, also characterizes the entire time-evolution process along which the dual field theory may thermalize

  11. Strong Subadditivity, Null Energy Condition and Charged Black Holes

    Caceres, Elena; Pedraza, Juan F; Tangarife, Walter

    2014-01-01

    Using the Hubeny-Rangamani-Takayanagi (HRT) conjectured formula for entanglement entropy in the context of the AdS/CFT correspondence with time-dependent backgrounds, we investigate the relation between the bulk null energy condition (NEC) of the stress-energy tensor with the strong sub-additivity (SSA) property of entanglement entropy in the boundary theory. In a background that interpolates between an AdS to an AdS-Reissner-Nordstrom-type geometry, we find that generically there always exists a critical surface beyond which the violation of NEC would naively occur. However, the extremal area surfaces that determine the entanglement entropy for the boundary theory, can penetrate into this forbidden region only for certain choices for the mass and the charge functions in the background. This penetration is then perceived as the violation of SSA in the boundary theory. We also find that this happens only when the critical surface lies above the apparent horizon, but not otherwise. We conjecture that SSA, which...

  12. Effects of Ions Charge-Mass Ratio on Energy and Energy Spread of Accelerated Ions in Laser Driven Plasma

    SANG Hai-Bo; DENG Shi-Qiang; XIE Bai-Song

    2013-01-01

    Effects of ions charge-mass ratio on energy and energy spread of accelerated ions in laser driven plasma are investigated in detail by proposing a simple double-layer model for a foil target driven by an ultrastrong laser.The radiation pressure acceleration mechanism plays an important role on the studied problem.For the ions near the plasma mirror,i.e.electrons layer,the dependence of ions energy on their charge-mass ratio is derived theoretically.It is found that the larger the charge-mass ratio is,the higher the accelerated ions energy gets.For those ions far away from the layer,the dependence of energy and energy spread on ions charge-mass ratio are also obtained by numerical performance.It exhibits that,as ions charge-mass ratio increases,not only the accelerated ions energy but also the energy spread will become large.

  13. Isospin Effect of Charged Particle Multiplicity in Intermediate Energy Heavy Ion Collisions

    HuRongjiang; WuHeyu; JinGenming; ZhuYongtai; DuanLimin; XiaoZhigang; WangHongwei

    2003-01-01

    The dependences of He and intermediate mass fragments (IMF) production rates in the reactions 55 MeV/u 40Ar+58,64 Ni on the isospin, impact parameter and primary excitation energy of the reaction nuclear system were studied by using the 4π charged particle multi-detector array system (MUDAL). For the mentioned two reaction systems, the measured He particle contribution in the total charged particle multiplicity increases with increasing the total charged particle multiplicity but for the contribution of IMFs in the total charged particle multiplicity increases with increasing the total charged particle multiplicity at lower total charged particle multiplicities, and latter on it drops down with further increasing of the total charged particle multiplicities (see Fig.l). The experimental results of these two reaction systems with the same nuclear charge indicate that the contribution of He and IMFs in the total charged particle multiplicities are obviously isospin dependent.

  14. High Energy Ionic Charge State Composition In Recent Large Solar Energetic Particle Events

    Labrador, A. W.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C.; von Rosenvinge, T. T.

    2003-01-01

    The ionic charge states of solar energetic particles (SEPs) provide information on the temperature of source materials and on conditions during acceleration and transport. SAMPEX/MAST measures mean ionic charge states at > 15 MeV/nuc using the geomagnetic rigidity filter technique. Charge state measurements by MAST for gradual SEP events suggest a continuum of charge states correlated with abundance ratios for a variety of elements, similar to what is observed at lower energies. In case...

  15. Charged Polymer Membranes for Environmental/Energy Applications.

    Kamcev, Jovan; Freeman, Benny D

    2016-06-01

    Ion exchange membranes are used in various membrane-based processes (e.g., electrodialysis, fuel cells). Charged solute transport is largely governed by the charged groups on the polymer backbone. In this review, fundamental relationships describing salt permeability and ionic conductivity, as well as water permeability, in charged polymers are developed within the framework of the Nernst-Planck and solution-diffusion models. The influence of fixed charge groups and polymer structure on water sorption and diffusion is discussed. Current understanding of ion partitioning in charged polymers, focusing on the use of thermodynamic models (i.e., Donnan theory) to describe such phenomena, is summarized. Ion diffusivity data from the literature are interpreted using a model developed by Mackie and Meares to assess relative and absolute effects of the polymer and fixed charge groups on ion diffusivity. Furthermore, membrane requirements for several important technologies are listed. Knowledge gaps and opportunities for fundamental research are also discussed. PMID:26979410

  16. Charge Retention in Quantized Energy Levels of Nanocrystals

    Dana, Aykutlu; Akca, Imran; Ergun, Orcun; Aydinli, Atilla; Turan, Rasit; Finstad, Terje

    2006-01-01

    Understanding charging mechanisms and charge retention dynamics of nanocrystal memory devices is important in optimization of device design. Capacitance spectroscopy on PECVD grown germanium nanocrystals embedded in a silicon oxide matrix was performed. Dynamic measurements of discharge dynamics are carried out. Charge decay is modelled by assuming storage of carriers in the ground states of nanocrystals and that the decay is dominated by direct tunnelling. Discharge rates are calculated usin...

  17. Dissociation of OCS by high energy highly charged ion impact

    OCS is an important molecule with immense biological, chemical and astrophysical significance. Various dissociation channels of OCSq+ (where q = 2 to 4), formed in the interaction of 5 MeV u-1 Si12+ ion beam with neutral OCS, have been studied using recoil-ion momentum spectroscopy. The concerted and/or sequential nature of dissociation is inferred from the shape and slope of the coincidence islands in the 2D coincidence map. It is observed that the C+ + S+ + O channel results from concerted as well as sequential decay of OCS2+. However the other channels originate purely from the concerted process in which the two terminal fragments (oxygen and sulphur) fly back to back and the central carbon fragment is left with negligible momentum. The kinetic energy release (KER) distributions for all the fragmentation channels arising from the dissociation of OCSq+ (where q = 2 to 4) have been measured and compared with the available data in the literature. It is observed that the KER values for complete Coulomb fragmentation channels are much smaller than those of incomplete Coulomb fragmentation cases and the KER increases with the increasing charge states of the parent molecular ions. From the momentum correlation map, we estimated the geometry of the precursor molecular ion undergoing three-body dissociation and inferred that bent dissociative states are involved in most of the fragmentation channels of OCSq+. (authors)

  18. The self-energy of a charged particle in the presence of a topological defect distribution

    De Carvalho, A M M; Furtado, C; Moraes, Fernando; Furtado, Claudio

    2004-01-01

    In this work we study a charged particle in the presence of both a continuous distribution of disclinations and a continuous distribution of edge dislocations in the framework of the geometrical theory of defects. We obtain the self-energy for a single charge both in the internal and external regions of either distribution. For both distributions the result outside the defect distribution is the self-energy that a single charge experiments in the presence of a single defect.

  19. N(+)-N long-range interaction energies and resonance charge exchange

    Stallcop, J. R.; Partridge, H.

    1985-01-01

    The aerothermodynamic studies of proposed space missions require atmospheric charge-transfer data. N2(+) eigenstate energies are calculated with use of the complete-active-space self-consistent-field method with an extended Gaussian basis set. The N(+)-N charge-exchange cross section, determined from these energies, agrees with merged-beam measurements. This contradicts the previous theoretical conclusion. A simple physical description of the long-range interaction is presented and should expedite future charge-transfer studies.

  20. Correlated inter-domain motions in adenylate kinase.

    Santiago Esteban-Martín

    2014-07-01

    Full Text Available Correlated inter-domain motions in proteins can mediate fundamental biochemical processes such as signal transduction and allostery. Here we characterize at structural level the inter-domain coupling in a multidomain enzyme, Adenylate Kinase (AK, using computational methods that exploit the shape information encoded in residual dipolar couplings (RDCs measured under steric alignment by nuclear magnetic resonance (NMR. We find experimental evidence for a multi-state equilibrium distribution along the opening/closing pathway of Adenylate Kinase, previously proposed from computational work, in which inter-domain interactions disfavour states where only the AMP binding domain is closed. In summary, we provide a robust experimental technique for study of allosteric regulation in AK and other enzymes.

  1. Inorganic electret with enhanced charge stability for energy harvesting

    Wang, Fei; Hansen, Ole

    2013-01-01

    We report a new surface treatment of inorganic electret materials which enhances the charge stability. Coating the surfaces with 1H, 1H, 2H, 2H - perfluorodecyltrichlorosilane (FDTS) makes the electret surface more hydrophobic which improves the surface charge stability under high humidity condit...

  2. Energy and charge transfer in ionized argon coated water clusters

    Kočišek, Jaroslav; Lengyel, Jozef; Fárník, Michal; Slavíček, P.

    2013-01-01

    Roč. 139, č. 21 (2013), s. 214308. ISSN 0021-9606 R&D Projects: GA ČR GAP208/11/0161 EU Projects: European Commission(XE) 238671 - ICONIC Institutional support: RVO:61388955 Keywords : Charged clusters * Charged fragments * Complex reactions Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.122, year: 2013

  3. Charged species in dielectric liquids generated by high energy radiation

    The main subject of Part I of this thesis is the investigation of the kinetics of the geminate recombination of the charged species, in relation to the yield of scavenging of the charged species and the initial spatial distribution. The geminate charge recombination kinetics in cyclohexane is investigated and the relation with the charge scavenging is considered. The geminate ion kinetics in liquid CCl4 is considered and the scavenging of excess electrons by CH3Br in cyclohexane, n-hexane and isooctane is treated in some detail. From the measurements of the microwave absorption the product of the yield and mobilities of the charged species is obtained. Provided the geminate kinetics is known it is possible to determine the mobility and the reactivity towards solutes of the charged species from measurements on a time scale on which the geminate recombination takes place. This is of importance when the charged species under investigation is short lived (e.g. because of reaction with impurities). In this way the mobility and reactivity of the negative species in liquid hexafluorobenzene could be studied. While C6F6 efficiently captures electrons in the gas phase as well as in hydrocarbon liquids, in pure liquid C6F6 efficient migration of the negative charge takes place. The study of the nature of this phenomenon is the subject of Part II. (Auth.)

  4. Dependence of plasmon excitation energy on filler material in interaction of charged particle with filled nanotubes

    Bahari, A., E-mail: bahari.a@lu.ac.i [Department of Physics, Lorestan University, Lorestan (Iran, Islamic Republic of); Mohamadi, A. [Department of Physics, Shiraz Payaem Noor University, Fars (Iran, Islamic Republic of)

    2010-10-15

    The interaction of charged particles with filled single-walled metallic nanotubes (SWMNT) has been investigated. Numerical results for the plasmon energy as a function of the wave vector are presented when the charged particle is outside the nanotube. Dependence of the plasmon energy on ratio of plasma frequency of the filler and SWMNT has been shown.

  5. Fast Charging and Smart Charging Tests for Electric Vehicles Batteries Using Renewable Energy

    Forero Camacho, Oscar Mauricio; Mihet-Popa, Lucian

    2016-01-01

    Electric Vehicles (EV) technologies are still relatively new and under strong development. Although some standardized solutions are being promoted and becoming a new trend, there is an outstanding need for common platforms and sharing of knowledge and core technologies. This paper presents...... the development of a test platform, including three Li-ion batteries designed for EV applications, and three associated bi-directional power converters, for testing impacts on different advanced loadings of EV batteries. Different charging algorithms/profiles have been tested, including constant current and power...... of both tests in terms of regulation of the aggregated local power, power capacity and the power exchange with the grid. The smart charging tests performed have demonstrated that even with a simple control algorithm, without any forecasting, it is possible to provide the required charging and at the same...

  6. Modification of adenylate cyclase by photoaffinity analogs of forskolin

    Ho, L.T.; Nie, Z.M.; Mende, T.J.; Richardson, S.; Chavan, A.; Kolaczkowska, E.; Watt, D.S.; Haley, B.E.; Ho, R.J. (Univ. of Miami School of Medicine, FL (USA))

    1989-01-01

    Photoaffinity labeling analogs of the adenylate cyclase activator forskolin (PF) have been synthesized, purified and tested for their effect on preparations of membrane-bound, Lubrol solubilized and forskolin affinity-purified adenylate cyclase (AC). All analogs of forskolin significantly activated AC. However, in the presence of 0.1 to 0.3 microM forskolin, the less active forskolin photoaffinity probes at 100 microM caused inhibition. This inhibition was dose-dependent for PF, suggesting that PF may complete with F for the same binding site(s). After cross-linking (125I)PF-M to either membrane or Lubrol-solubilized AC preparations by photolysis, a radiolabeled 100-110 kDa protein band was observed after autoradiography following SDS-PAGE. F at 100 microM blocked the photoradiolabeling of this protein. Radioiodination of forskolin-affinity purified AC showed several protein bands on autoradiogram, however, only one band (Mr = 100-110 kDa) was specifically labeled by (125I)PF-M following photolysis. The photoaffinity-labeled protein of 100-110 kDa of AC preparation of rat adipocyte may be the catalytic unit of adenylate cyclase of rat adipocyte itself as supported by the facts that (a) no other AC-regulatory proteins are known to be of this size, (b) the catalytic unit of bovine brain enzyme is in the same range and (c) this PF specifically stimulates AC activity when assayed alone, and weekly inhibits forskolin-activation of cyclase. These studies indicate that radiolabeled PF probes may be useful for photolabeling and detecting the catalytic unit of adenylate cyclase.

  7. Modification of adenylate cyclase by photoaffinity analogs of forskolin

    Photoaffinity labeling analogs of the adenylate cyclase activator forskolin (PF) have been synthesized, purified and tested for their effect on preparations of membrane-bound, Lubrol solubilized and forskolin affinity-purified adenylate cyclase (AC). All analogs of forskolin significantly activated AC. However, in the presence of 0.1 to 0.3 microM forskolin, the less active forskolin photoaffinity probes at 100 microM caused inhibition. This inhibition was dose-dependent for PF, suggesting that PF may complete with F for the same binding site(s). After cross-linking [125I]PF-M to either membrane or Lubrol-solubilized AC preparations by photolysis, a radiolabeled 100-110 kDa protein band was observed after autoradiography following SDS-PAGE. F at 100 microM blocked the photoradiolabeling of this protein. Radioiodination of forskolin-affinity purified AC showed several protein bands on autoradiogram, however, only one band (Mr = 100-110 kDa) was specifically labeled by [125I]PF-M following photolysis. The photoaffinity-labeled protein of 100-110 kDa of AC preparation of rat adipocyte may be the catalytic unit of adenylate cyclase of rat adipocyte itself as supported by the facts that [a] no other AC-regulatory proteins are known to be of this size, [b] the catalytic unit of bovine brain enzyme is in the same range and [c] this PF specifically stimulates AC activity when assayed alone, and weekly inhibits forskolin-activation of cyclase. These studies indicate that radiolabeled PF probes may be useful for photolabeling and detecting the catalytic unit of adenylate cyclase

  8. Adenylate cyclase toxin-hemolysin relevance for pertussis vaccines

    Šebo, Peter; Osička, Radim; Mašín, Jiří

    2014-01-01

    Roč. 13, č. 10 (2014), s. 1215-1227. ISSN 1476-0584 R&D Projects: GA ČR GA13-14547S; GA ČR(CZ) GAP302/11/0580; GA ČR GAP302/12/0460 Institutional support: RVO:61388971 Keywords : adenylate cyclase toxin * antigen delivery * Bordetella pertussis Subject RIV: EE - Microbiology, Virology Impact factor: 4.210, year: 2014

  9. A parametrisation of the energy loss distributions of charged particles and its applications for silicon detectors

    Sikler, Ferenc

    2012-01-01

    The energy loss distribution of charged particles in silicon is approximated by a simple analytical parametrization. Its use is demonstrated through several examples. With the help of energy deposits in sensing elements of the detector, the position of track segments and the corresponding deposited energy are estimated with improved accuracy and less bias. The parametrization is successfully used to estimate the energy loss rate of charged particles, and it is applied to detector gain calibration tasks.

  10. Effects of cadmium on canine renal cortical adenylate cyclase

    The present studies examine the effects of cadmium (Cd2+) on adenylate cyclase activity in basolateral renal cortical membranes from normal dogs. Cd2+, in the dose range of 1 to 200 μM caused a dose-dependent inhibition of adenylate cyclase activity due to competitive inhibition with respect to the allosteric activator Mg2+. In addition, increasing Cd2+ concentrations from 0 to 25 μM resulted in a purely competitive inhibition with respect to ATP. In the absence of other divalent cations Cd2+ was a potent stimulator of basal adenylate cyclase activity, far more potent than the physiological activator of the system Mg2+. It is concluded that Cd2+ behaves as a partial agonist in this system, due to its ability to form a new enzymatic substrate complex: Cd-ATP, which competes with the physiological substrate Mg-ATP at the catalytic site of the enzyme. In addition, Cd2+ in the absence of other divalent cation stimulates basal enzyme activity, presumably through interaction at an additional site, closely related to the allosteric metal regulatory site of this enzyme system

  11. Beamline for low-energy transport of highly charged ions at HITRAP

    A beamline for transport of highly charged ions with energies as low as a few keV/charge has been constructed and commissioned at GSI. Complementary to the existing infrastructure of the HITRAP facility for deceleration of highly charged ions from the GSI accelerator, the new beamline connects the HITRAP ion decelerator and an EBIT with the associated experimental setups. Therefore, the facility can now transport the decelerated heavy highly charged ions to the experiments or supply them offline with medium-heavy highly charged ions from the EBIT, both at energies as low as a few keV/charge. Here we present the design of the 20 m long beamline with the corresponding beam instrumentation, as well as its performance in terms of energy and transport efficiency

  12. Beamline for low-energy transport of highly charged ions at HITRAP

    Andelkovic, Z., E-mail: z.andelkovic@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Herfurth, F.; Kotovskiy, N. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); König, K.; Maaß, B.; Murböck, T. [Technische Universität Darmstadt (Germany); Neidherr, D. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Schmidt, S. [Technische Universität Darmstadt (Germany); Johannes Gutenberg-Universität Mainz (Germany); Steinmann, J. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Hochschule Darmstadt (Germany); Vogel, M.; Vorobjev, G. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany)

    2015-09-21

    A beamline for transport of highly charged ions with energies as low as a few keV/charge has been constructed and commissioned at GSI. Complementary to the existing infrastructure of the HITRAP facility for deceleration of highly charged ions from the GSI accelerator, the new beamline connects the HITRAP ion decelerator and an EBIT with the associated experimental setups. Therefore, the facility can now transport the decelerated heavy highly charged ions to the experiments or supply them offline with medium-heavy highly charged ions from the EBIT, both at energies as low as a few keV/charge. Here we present the design of the 20 m long beamline with the corresponding beam instrumentation, as well as its performance in terms of energy and transport efficiency.

  13. Action of ''Bipenst'' preparation and dimethylsulfoxide on the adenyl nucleotide content in liver of irradiated animals

    Action of parenteral administration of a biostimulator ''Bipenst'' and a 10; dimethylsulfoxide solution on the level of adenyl nucleotides in the liver of rats subjected to a single whole-body irradiation (243 R) has been studied. It has been found that the level of adenyl nucleotides in the liver of irradiated animals decreases, and adenyl nucleotide content normalizes under the action of the preparations under study

  14. Measuring charge fluctuations in high-energy nuclear collisions

    Mrowczynski, Stanislaw

    2001-01-01

    Various measures of charge fluctuations in heavy-ion collisions are discussed. Advantages of the Phi-measure are demonstrated and its relation to other fluctuation measures is established. To get the relation, Phi is expressed through the moments of multiplicity distribution. We study how the measures act in the case of a `background' model which represents the classical hadron gas in equilibrium. The model assumes statistical particle production constrained by charge conservation. It also ta...

  15. A schematic model for energy and charge transfer in the chlorophyll complex

    Bohr, Henrik; Malik, F.B.

    2011-01-01

    A theory for simultaneous charge and energy transfer in the carotenoid-chlorophyll-a complex is presented here and discussed. The observed charge transfer process in these chloroplast complexes is reasonably explained in terms of this theory. In addition, the process leads to a mechanism to drive...... are in the range of pico-seconds and less. The change in electronic charge distribution in internuclear space as the system undergoes an electronic transition to a higher-energy state could, under appropriate physical conditions, lead to oscillating dipoles capable of transmitting energy from the...... ground state by fluorescence with no electron being transferred. In the process proposed herein, charge and energy both are transferred from donor to acceptor which can further de-excite by fluorescence. The charge transfer time scale involving an actual transfer of electron is in the pico-second range....

  16. Impact and energy deposition of slow, highly charged ions on a solid surface

    A plasma region in nanometer scale may be created by a highly charged ion impact on solid surface. The charge imbalance leads to enormous electric fields and may further induce Coulomb explosion due to electrostatic repulsion in the region. Thus, the highly charged ion is thus expected to be a powerful tool to induce surface modification in the nanometer scale. The Coulomb explosion model is applied in order to interpret the interaction mechanism and to understand the impact and energy deposition of highly charged ions on a solid surface, and to obtain the energy deposited by the ion. The energy deposition ratio is dependent on the material and charge. A high temperature and high pressure environment will be formed by the deposited energy, causing the atoms to swell up and a hillock nano-defect to be formed on surface. The height of hillock is estimated from the Coulomb explosion.

  17. Impact and energy deposition of slow, highly charged ions on a solid surface

    Wang, T.S. [School of Nuclear Science and Technology, Lanzhou University, Tianshuinan Road, Lanzhou 730000 (China); Yang, G.X. [School of Nuclear Science and Technology, Lanzhou University, Tianshuinan Road, Lanzhou 730000 (China)], E-mail: yanggx06@lzu.cn; Liu, S.J.; Xu, H.; Han, Y.C.; Xiang, Y.; Chen, L.; Yang, X.Y. [School of Nuclear Science and Technology, Lanzhou University, Tianshuinan Road, Lanzhou 730000 (China)

    2009-08-15

    A plasma region in nanometer scale may be created by a highly charged ion impact on solid surface. The charge imbalance leads to enormous electric fields and may further induce Coulomb explosion due to electrostatic repulsion in the region. Thus, the highly charged ion is thus expected to be a powerful tool to induce surface modification in the nanometer scale. The Coulomb explosion model is applied in order to interpret the interaction mechanism and to understand the impact and energy deposition of highly charged ions on a solid surface, and to obtain the energy deposited by the ion. The energy deposition ratio is dependent on the material and charge. A high temperature and high pressure environment will be formed by the deposited energy, causing the atoms to swell up and a hillock nano-defect to be formed on surface. The height of hillock is estimated from the Coulomb explosion.

  18. Characteristics of high efficiency current charging system for HTS magnet with solar energy

    Kim, Dae-Wook; Yoon, Yong-Soo; Chung, Yoon-Do; Jo, Hyun-Chul; Kim, Ho-Min; Oh, Sung-Kwun; Kim, Hyun-Ki; Oh, Jae-Gi; Ko, Tae-Kuk

    In terms of electrical energy, the technical fusion with solar energy system is promisingly applied in order to improve the efficiency in the power applications, since the solar energy system can convert an eternal electric energy in all-year-around. As one of such power applications, we proposed a current charging system for HTS magnet combined with solar energy (CHS). As this system can operate without external utility power to charge the HTS load magnet due to the solar energy, the operating efficiency is practically improved. The power converter, which is interfaced with solar energy and HTS magnet systems, plays an important role to transfer the stable electric energy and thus, the stabilized performance of the converter with solar energy system is one of essential factors. In this study, we investigated various charging performances under different operating conditions of the converter. In addition, operating characteristics have been analyzed by solving solar cell equivalent equations based on circuit simulation program.

  19. Long-Term Exposure to High Corticosterone Levels Inducing a Decrease of Adenylate Kinase 1 Activity

    ZHAO Yu'nan; SHEN Jia; SU Hui; HUANG Yufang; XING Dongming; DU Lijun

    2009-01-01

    Corticosterone, a principal glucocorticoid synthesized in the rodent adrenal cortex, can be cumula-tively toxic to hippocampal neurons, the cause of which is not known. The present study determined whether the cytosol adenylate kinase (AK) system was involved in the neuronal damage induced by long-term exposure to high corticosterone levels. We investigated the effects of long-term exposure to high corticosterone levels on AK1 activity, AK1 mRNA expression, and energy levels in cultured hippocampal neurons. The results show that long-term exposure to high corticosterone levels induces a reduction of the cultured hippocampal neuron viability, significantly reduces energy levels, and causes a time-dependant re-duction of the AK1 activity. These findings indicate that changes in the AK system might be the mechanism underlying neuronal damage induced by long-term exposure to high corticosterone levels.

  20. Instantaneous charge state of Uranium projectiles in fully ionized plasmas from energy loss experiments

    Morales, Roberto; Casas, David

    2016-01-01

    The instantaneous charge state of uranium ions traveling through a fully ionized hydrogen plasma has been theoretically studied and compared with one of the first energy loss experiments in plasmas, carried out at GSI-Darmstadt by Hoffmann \\textit{et al.} in the 90's. For this purpose, two different methods to estimate the instantaneous charge state of the projectile have been employed: (1) rate equations using ionization and recombination cross sections, and (2) equilibrium charge state formulas for plasmas. Also, the equilibrium charge state has been obtained using these ionization and recombination cross sections, and compared with the former equilibrium formulas. The equilibrium charge state of projectiles in plasmas is not always reached, it depends mainly on the projectile velocity and the plasma density. Therefore, a non-equilibrium or an instantaneous description of the projectile charge is necessary. The charge state of projectile ions cannot be measured, except after exiting the target, and experime...

  1. High Energy Ionic Charge State Composition in Large Solar Energetic Particle Events

    Labrador, A. W.; Leske, R. A.; Mewaldt, R. A.; Cummings, A. C.; Stone, E. C.; von Rosenvinge, T. T.

    2001-01-01

    Measurements of ionic charge states in solar energetic particle (SEP) events have been made at relatively high energies (> 15 MeV/nucleon) with the Mass Spectrometer Telescope (MAST) on board the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) satellite using the Earth's magnetic field as a particle rigidity filter. We have examined the largest SEP events of solar cycle 23 and determined ionic charge states of Fe and other elements in several of these events. The mean charge s...

  2. Scaling Of The Coulomb Energy Due To Quantum Fluctuations In The Charge Of A Quantum Dot

    Molenkamp, L.W.; Flensberg, Karsten; Kemerink, M.

    1995-01-01

    The charging energy of a quantum dot is measured through the effect of its potential on the conductance of a second dot. This technique allows a measurement of the scaling of the dot's charging energy with the conductance of the tunnel barriers leading to the dot. We find that the charging energy...... scales quadratically with the reflection probability of the barriers. In a second experiment we study the transition from a single to a double-dot which exhibits a scaling behavior linear in the reflection probability. The observed power-laws agree with a recent theory....

  3. Direct observation of space charge dynamics by picosecond low-energy electron scattering

    Cirelli, C.; Hengsberger, M.; Dolocan, A.; Over, H.; Osterwalder, J.; Greber, T.

    2009-01-01

    The transient electric field governing the dynamics of space charge is investigated by time- and energy-resolved low-energy electron scattering. The space charge above a copper target is produced by high-intensity femtosecond laser pulses. The pump-probe experiment has a measured temporal resolution of better than 35 ps at 55 eV probe electron energy. The probe electron acceleration due to space charge is reproduced within a 3-dimensional non-relativistic model, which determines an effective ...

  4. Energy and Charge Transfer from Guest to Host in Doped Organic Electroluminescent Devices

    李宏建; 彭景翠; 许雪梅; 瞿述; 罗小华; 赵楚军

    2002-01-01

    The luminescence properties of doped organic electroluminescent devices are explained by means off Hamiltonian model. The results show that there is a corresponding relation between the amount of transferred charge and the change of the energy originating from charge transfer, and the relation can be influenced by dopant concentration.As the amount of transferred charge increases, the total energy decreases and the luminescence intensity increases.Therefore, we deduce that the energy transfer from guest to host may be derived from the charge transfer. For a given organic electroluminescent device, the maximum value of the conductivity can be observed in a specific dopant concentration. The calculated results show that the greater the transferred charges, the higher the conductivities in doped organic electroluminescent devices. The results agree basically with experimental results.

  5. X-UV SPECTROSCOPY OF LOW ENERGY CHARGE EXCHANGE COLLISIONS

    Bliman, S.; Bonnet, J.; Bonnefoy, M.; Dousson, S.; Fleury, A.; Hitz, D.; Lu Dac, T.; Mayo, M.

    1986-01-01

    In the field of hot plasmas, it is well known that a knowledge of the relation between collisions and radiation is needed. We show that considering the charge exchange process in which a highly charged, low velocity ion impinges on an atom, we have an X-UV light source allowing new developments. Basically, at velocities less than the atomic unit (vo = 2.2 108 cm/s), the capture of one electron will leave the projectile ion in an excited state. The most probably populated level np is dependant...

  6. A Control Algorithm for Electric Vehicle Fast Charging Stations Equipped with Flywheel Energy Storage Systems

    Sun, Bo; Dragicevic, Tomislav; Freijedo Fernandez, Francisco Daniel;

    2016-01-01

    This paper proposes a control strategy for plugin electric vehicle (PEV) fast charging station (FCS) equipped with a flywheel energy storage system (FESS). The main role of the FESS is not to compromise the predefined charging profile of PEV battery during the provision of a hysteresis-type active...

  7. Design & Implementation of a Mobile Phone Charging System Based on Solar Energy Harvesting

    Qutaiba I. Ali

    2011-06-01

    Full Text Available The ability to harvest energy from the environment represents an important technology area that promises to eliminate wires and battery maintenance for many important applications and permits deploying self powered devices. This paper suggests the use of a solar energy harvester to charge mobile phone devices. In the beginning, a comprehensive overview to the energy harvesting concept and technologies is presented. Then the design procedure of our energy harvester was detailed. Our prototype solar energy harvester proves its efficiency to charge the aimed batteries under sunlight or an indoor artificial light.

  8. Control of charging energy in chemically assembled nanoparticle single-electron transistors

    We show the control of a charging energy in chemically assembled nanoparticle single-electron transistors (SETs) by altering the core diameter of Au nanoparticles. The charging energy is a fundamental parameter that decides the operating temperature of SETs. Practical application of SETs requires us to regulate the value of the charging energy by tuning the diameter of quantum dots. In this study, we used 3.0, 5.0 and 6.2 nm diameter synthesized Au nanoparticles as a quantum dot in the SETs. The total capacitances and charging energy of the SETs were evaluated from the rhombic Coulomb diamonds attributed to a single Coulomb island. The capacitance and charging energy matched with a concentric sphere model much better than with a simple sphere model. The operating temperatures of the SETs suggested that a charging energy 2.2 times greater than the thermal energy was required for stable operation, in theory. These results will help us to select an appropriate core diameter for the Au nanoparticles in practical SETs. (paper)

  9. Direct observation of space charge dynamics by picosecond low-energy electron scattering

    Cirelli, C.; Hengsberger, M.; Dolocan, A.; Over, H.; Osterwalder, J.; Greber, T.

    2009-01-01

    The transient electric field governing the dynamics of space charge is investigated by time- and energy-resolved low-energy electron scattering. The space charge above a copper target is produced by high-intensity femtosecond laser pulses. The pump-probe experiment has a measured temporal resolution of better than 35 ps at 55 eV probe electron energy. The probe electron acceleration due to space charge is reproduced within a 3-dimensional non-relativistic model, which determines an effective number of electrons in the space charge cloud and its initial diameter. Comparison of the simulations with the experiments indicates a Coulomb explosion, which is consistent with transients in the order of 1 ns, the terminal kinetic energy of the cloud and the thermoemission currents predicted by the Richardson-Dushman formula.

  10. Search for Fractionally Charged Nuclei in High-Energy Oxygen-Lead Collisions

    2002-01-01

    We propose to use stacks of CR-39 plastic track detectors to look for fractionally charged projectile fragments produced in collisions of high-energy oxygen, sulfur, and calcium nuclei with a lead target. The expected charge resolution is @s^z~=~0.06e for fragments with 17e/3~@$<$~Z~@$<$~23e/3. We request that two target + stack assemblies be exposed to 1~x~10|5 oxygen nuclei at maximum available energy.

  11. Charge-state-dependent energy loss of slow ions. II. Statistical atom model

    Wilhelm, Richard A.; Möller, Wolfhard

    2016-05-01

    A model for charge-dependent energy loss of slow ions is developed based on the Thomas-Fermi statistical model of atoms. Using a modified electrostatic potential which takes the ionic charge into account, nuclear and electronic energy transfers are calculated, the latter by an extension of the Firsov model. To evaluate the importance of multiple collisions even in nanometer-thick target materials we use the charge-state-dependent potentials in a Monte Carlo simulation in the binary collision approximation and compare the results to experiment. The Monte Carlo results reproduce the incident charge-state dependence of measured data well [see R. A. Wilhelm et al., Phys. Rev. A 93, 052708 (2016), 10.1103/PhysRevA.93.052708], even though the experimentally observed charge exchange dependence is not included in the model.

  12. Beam Energy and System Size Dependence of Dynamical Net Charge Fluctuations

    STAR Coll

    2008-07-21

    We present measurements of net charge fluctuations in Au + Au collisions at {radical}s{sub NN} = 19.6, 62.4, 130, and 200 GeV, Cu + Cu collisions at {radical}s{sub NN} = 62.4, 200 GeV, and p + p collisions at {radical}s = 200 GeV using the dynamical net charge fluctuations measure {nu}{sub {+-},dyn}. We observe that the dynamical fluctuations are non-zero at all energies and exhibit a modest dependence on beam energy. A weak system size dependence is also observed. We examine the collision centrality dependence of the net charge fluctuations and find that dynamical net charge fluctuations violate 1/N{sub ch} scaling, but display approximate 1/N{sub part} scaling. We also study the azimuthal and rapidity dependence of the net charge correlation strength and observe strong dependence on the azimuthal angular range and pseudorapidity widths integrated to measure the correlation.

  13. Beam-energy and system-size dependence of dynamical net charge fluctuations

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Baumgart, S.; Beavis, D. R.; Bellwied, R.; Benedosso, F.; Betts, R. R.; Bhardwaj, S.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bueltmann, S.; Burton, T. P.; Bystersky, M.; Cai, X. Z.; Caines, H.; Sánchez, M. Calderón De La Barca; Callner, J.; Catu, O.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K. E.; Christie, W.; Chung, S. U.; Clarke, R. F.; Codrington, M. J. M.; Coffin, J. P.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; de Moira, M. M.; Dedovich, T. G.; Dephillips, M.; Derevschikov, A. A.; de Souza, R. Derradi; Didenko, L.; Dictel, T.; Djawotho, P.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, F.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Edwards, W. R.; Efimov, L. G.; Elhalhuli, E.; Elnimr, M.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Eun, L.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Feng, A.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, C. A.; Gaillard, L.; Gangadharan, D. R.; Ganti, M. S.; Garcia-Solis, E.; Ghazikhanian, V.; Ghosh, P.; Gorbunov, Y. N.; Gordon, A.; Grebenyuk, O.; Grosnick, D.; Grube, B.; Guertin, S. M.; Guimaraes, K. S. F. F.; Gupta, A.; Gupta, N.; Guryn, W.; Hallman, T. J.; Hamed, A.; Harris, J. W.; He, W.; Heinz, M.; Heppelmann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Huang, H. Z.; Humanic, T. J.; Huo, L.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jena, C.; Jin, F.; Jones, C. L.; Jones, P. G.; Joseph, J.; Judd, E. G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V. Yu.; Kiryluk, J.; Kisiel, A.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Kopytine, M.; Kotchenda, L.; Kouchpil, V.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Kuhn, C.; Kumar, A.; Kumar, L.; Kurnadi, P.; Lamont, M. A. C.; Landgraf, J. M.; Lapointe, S.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C.-H.; Levine, M. J.; Li, C.; Li, Y.; Lin, G.; Lin, X.; Lindenbaum, S. J.; Lisa, M. A.; Liu, F.; Liu, J.; Liu, L.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Ludlam, T.; Lynn, D.; Ma, G. L.; Ma, J. G.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Matis, H. S.; Matulenko, Yu. A.; McShane, T. S.; Meschanin, A.; Millane, J.; Miller, M. L.; Minaev, N. G.; Mioduszewski, S.; Mischke, A.; Mitchell, J.; Mohanty, B.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; Nepali, C.; Netrakanti, P. K.; Ng, M. J.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Okada, H.; Okorokov, V.; Olson, D.; Pachr, M.; Pal, S. K.; Panebratsev, Y.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S. C.; Planinic, M.; Pluta, J.; Poljak, N.; Porile, N.; Poskanzer, A. M.; Potekhin, M.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ridiger, A.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M. J.; Rykov, V.; Sahoo, R.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sarsour, M.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S. S.; Shi, X.-H.; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Skoby, M. J.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, T. D. S.; Staszak, D.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Subba, N. L.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Symons, T. J. M.; de Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Timoshenko, S.; Tokarev, M.; Tram, V. N.; Trattner, A. L.; Trentalange, S.; Tribble, R. E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Buren, G. Van; van der Kolk, N.; van Leeuwen, M.; Molen, A. M. Vander; Varma, R.; Vasconcelos, G. M. S.; Vasilevski, I. M.; Vasiliev, A. N.; Videbaek, F.; Vigdor, S. E.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.; Waggoner, W. T.; Wang, F.; Wang, G.; Wang, J. S.; Wang, Q.; Wang, X.; Wang, X. L.; Wang, Y.; Webb, J. C.; Westfall, G. D.; Whitten, C., Jr.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, J.; Wu, Y.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yepes, P.; Yoo, I.-K.; Yue, Q.; Zawisza, M.; Zbroszczyk, H.; Zhan, W.; Zhang, H.; Zhang, S.; Zhang, W. M.; Zhang, Y.; Zhang, Z. P.; Zhao, Y.; Zhong, C.; Zhou, J.; Zoulkarneev, R.; Zoulkarneeva, Y.; Zuo, J. X.

    2009-02-01

    We present measurements of net charge fluctuations in Au+Au collisions at sNN=19.6, 62.4, 130, and 200 GeV, Cu+Cu collisions at sNN=62.4 and 200 GeV, and p+p collisions at s=200 GeV using the dynamical net charge fluctuations measure ν+-,dyn. We observe that the dynamical fluctuations are nonzero at all energies and exhibit a modest dependence on beam energy. A weak system size dependence is also observed. We examine the collision centrality dependence of the net charge fluctuations and find that dynamical net charge fluctuations violate 1/Nch scaling but display approximate 1/Npart scaling. We also study the azimuthal and rapidity dependence of the net charge correlation strength and observe strong dependence on the azimuthal angular range and pseudorapidity widths integrated to measure the correlation.

  14. Economic Evaluation of a Solar Charged Thermal Energy Store for Space Heating

    Melo, Manuel

    2013-01-01

    A thermal energy store corrects the misalignment of heating demand in the winter relative to solar thermal energy gathered in the summer. This thesis reviews the viability of a solar charged hot water tank thermal energy store for a school at latitude 56.25N, longitude -120.85W

  15. Activation energies for gas-phase dissociations of multiply charged ions from electrospay ionization mass spectrometry

    Busman, M.; Rockwood, A.L.; Smith, R.D. [Pacific Northwest Lab., Richland, WA (United States)

    1992-03-19

    The reactions of multiply protonated melittin molecular ions of various charge states produced from an electrospray ionization source have been studied. The flow of ions entrained in gas through a heated metal capillary inlet serves as a reaction vessel for gas-phase measurements of molecular ion reaction rates using mass spectrometry. Activation energies for the unimolecular dissociation reactions are calculated from the temperature dependence of the reaction kinetics. The differences in activation energies for the reactions of the different charge states are attributed to the destabilizing effect of Coulombic repulsion for high charged ions. 18 refs., 3 figs., 1 tab.

  16. Scintillation light produced by low-energy beams of highly-charged ions

    M. Vogel; Winters, D.F.A.; Ernst, H.; H. Zimmermann; Kester, O.

    2007-01-01

    Measurements have been performed of scintillation light intensities emitted from various inorganic scintillators irradiated with low-energy beams of highly-charged ions from an electron beam ion source (EBIS) and an electron cyclotron resonance ion source (ECRIS). Beams of xenon ions Xe$^{q+}$ with various charge states between $q$=2 and $q$=18 have been used at energies between 5 keV and 17.5 keV per charge generated by the ECRIS. The intensity of the beam was typically varied between 1 and ...

  17. The role of electron capture and energy exchange of positively charged particles passing through matter

    Ulmer, W.

    2011-01-01

    The conventional treatment of the Bethe-Bloch equation for protons accounts for electron capture at the end of the projectile track by the small Barkas correction. This is only a possible way for protons, whereas for light and heavier charged nuclei the exchange of energy and charge along the track has to be accounted for by regarding the projectile charge q as a function of the residual energy. This leads to a significant modification of the Bethe-Bloch equation, otherwise the range in a med...

  18. Charge-transfer energy in closed-shell ion-atom interactions. [for H and Li ions in He

    Alvarez-Rizzatti, M.; Mason, E. A.

    1975-01-01

    The importance of charge-transfer energy in the interactions between closed-shell ions and atoms is investigated. Ab initio calculations on H(plus)-He and Li(plus)-He are used as a guide for the construction of approximate methods for the estimation of the charge-transfer energy for more complicated systems. For many alkali ion-rate gas systems the charge-transfer energy is comparable to the induction energy in the region of the potential minimum, although for doubly charged alkaline-earth ions in rare gases the induction energy always dominates. Surprisingly, an empirical combination of repulsion energy plus asymptotic induction energy plus asymptotic dispersion energy seems to give a fair representation of the total interaction, especially if the repulsion energy is parameterized, despite the omission of any explicit charge-transfer contribution. More refined interaction models should consider the charge-transfer energy contribution.

  19. Investigation of space-charge compensation with residual-gas-ion energy analyser

    Low energy beam transport of high perveance beams with magnetic quadrupole focusing requires a high degree of space-charge compensation. Furthermore the build-up time of space-charge compensation has to be short compared to the beam-pulse duration. In order to study the space-charge compensation in the drift sections between the focusing elements of the existing GSI UNTLAC injector, the energy spectrum of the residual gas ions produced by the beam and accelerated radially by the space-charge potential can be measured. Hereto a compact electrostatic energy analyser of the Hughes-Rojansky type has been built allowing for time integrated as well as time resolved measurements. First measurements in time integrating mode have been performed. (author)

  20. Measurement of the atmospheric muon charge ratio at TeV energies with MINOS

    Adamson, P.; Andreopoulos, C.; Arms, K.E.; Armstrong, R.; Auty, D.J.; Avvakumov, S.; Ayres, D.S.; Baller, B.; Barish, B.; Barnes, P.D., Jr.; Barr, G.; /Fermilab /University Coll. London /Rutherford /Minnesota U. /Indiana U. /Sussex U. /Stanford U., Phys. Dept. /Argonne /Caltech /LLNL, Livermore /Oxford U.

    2007-05-01

    The 5.4 kton MINOS far detector has been taking charge-separated cosmic ray muon data since the beginning of August, 2003 at a depth of 2070 m.w.e. in the Soudan Underground Laboratory, Minnesota, USA. The data with both forward and reversed magnetic field running configurations were combined to minimize systematic errors in the determination of the underground muon charge ratio. When averaged, two independent analyses find the charge ratio underground to be N{sub {mu}}+/N{sub {mu}}-=1.374{+-}0.004(stat)-0.010{sup +0.012}(sys). Using the map of the Soudan rock overburden, the muon momenta as measured underground were projected to the corresponding values at the surface in the energy range 1-7 TeV. Within this range of energies at the surface, the MINOS data are consistent with the charge ratio being energy independent at the 2 standard deviation level. When the MINOS results are compared with measurements at lower energies, a clear rise in the charge ratio in the energy range 0.3-1.0 TeV is apparent. A qualitative model shows that the rise is consistent with an increasing contribution of kaon decays to the muon charge ratio.

  1. Charged particle induced energy dispersive X-ray analysis

    This review article deals with the X-ray emission induced by heavy, charged particles and the use of this process as an analytical method (PIXE). The physical processes involved, X-ray emission and the various reactions contributing to the background, are described in some detail. The sensitivity is calculated theoretically and the results compared with practical experience. A discussion is given on how the sensitivity can be optimized. The experimental arrangements are described and the various technical problems discussed. The analytical procedure, especially the sample preparation, is described in considerable detail. A number of typical practical applications are discussed. (author)

  2. Heavy ion charge-state distribution effects on energy loss in plasmas

    Barriga-Carrasco, Manuel D.

    2013-10-01

    According to dielectric formalism, the energy loss of the heavy ion depends on its velocity and its charge density. Also, it depends on the target through its dielectric function; here the random phase approximation is used because it correctly describes fully ionized plasmas at any degeneracy. On the other hand, the Brandt-Kitagawa (BK) model is employed to depict the projectile charge space distribution, and the stripping criterion of Kreussler is used to determine its mean charge state . This latter criterion implies that the mean charge state depends on the electron density and temperature of the plasma. Also, the initial charge state of the heavy ion is crucial for calculating inside the plasma. Comparing our models and estimations with experimental data, a very good agreement is found. It is noticed that the energy loss in plasmas is higher than that in the same cold gas cases, confirming the well-known enhanced plasma stopping (EPS). In this case, EPS is only due to the increase in projectile effective charge Qeff, which is obtained as the ratio between the energy loss of each heavy ion and that of the proton in the same plasma conditions. The ratio between the effective charges in plasmas and in cold gases is higher than 1, but it is not as high as thought in the past. Finally, another significant issue is that the calculated effective charge in plasmas Qeff is greater than the mean charge state , which is due to the incorporation of the BK charge distribution. When estimations are performed without this distribution, they do not fit well with experimental data.

  3. A purely classical description of crossings of energy levels and spectroscopic signatures of charge exchange

    Charge exchange and crossings of corresponding energy levels that enhance charge exchange are strongly connected with problems of energy loss and diagnostics in high-temperature plasmas. Charge exchange has also been proposed as one of the most effective mechanisms for population inversion in the soft x-ray and VUV ranges. One area of the most fundamental theoretical importance in the study of charge exchange is the problem of electron terms in the field of two stationary Coulomb centres (TCC) of charges Z and Z' separated by a distance R. This involves fascinating atomic physics: the terms can have crossings and quasicrossings. These rich features of the TCC problem are also manifest in other areas of physics such as plasma spectroscopy: a quasicrossing of the TCC terms, by enhancing charge exchange, can result in an unusual structure (a dip) in the spectral line profile emitted by a Z-ion from a plasma consisting of both Z- and Z'-ions, as has been shown theoretically and experimentally. The paradigm is that these sophisticated features of the TCC problem and their flourishing applications are inherently quantum phenomena. In this paper we disprove this paradigm. We present a purely classical description of both the crossings of energy levels in the TCC problem and the dips in the corresponding spectral line profiles caused by the crossing (via enhanced charge exchange). Our classical description is based on first principles and does not use any model assumptions. (author)

  4. New analytical potential energy function for doubly charged diatomic molecules

    Wang Fan-Hou; Yang Chuan-Lu; Zhu Zheng-He; Jing Fu-Qian

    2005-01-01

    A new analytical potential function for doubly charged diatomic ions is proposed as V(R)=(∑k n=0anRn-1)exp(-ak+1R)+C/R,where an, ak+1 and C are parameters, and R is the nuclear distance. This function can be used to describe the potential curves for doubly charged diatomic ions with both potential minimum and maximum, or without any stationary point. As examples, potential functions of this form for ground states of BH2+, He22+ and HF2+ have been derived.The calculations using the theoretical method QCISD with basis set 6-311++G* have shown that the potential minimum of BH2+is at Rmin=0.147nm, the maximum at Rmax=0.185nm, and ΔE = Emax - Emin=0.062 eV; for He22+Rmin=0.0736nm, Rmax=0.105nm, and ΔE = Emax - Emin=0.71 eV. It is found that the potential curve for HF2+ is one with a singly repulsive branch. The force constants and spectroscopic data for BH2+ and He22+ have also been worked out.

  5. The charge ratio of the atmospheric muons at low energy

    From the nature of the muon production processes, it can be seen that the ratio of positive to negative cosmic muons has important information in both 'the atmospheric neutrino problem', and 'the hadronic interactions'. We have carried out an experiment for the measurement of the muon charge ratio in the cosmic ray flux in momentum range 0.112-0.178 GeV/c. The muon charge ratio is found to be 1.21±0.01 with a mean zenith angle of 32 deg. ±5 deg. . From the measurements it has been obtained a zenithal angle distribution of muons as I(θ)=I(0)cosnθ with n=1.95±0.13. An asymmetry has been observed in East-West directions because of the geomagnetic field. Meanwhile, in about the same momentum range, positive and negative muons have been studied on the basis of Monte Carlo simulations of the extensive air shower developement (Cosmic Ray Simulations for Kascade), using the Quark Gluon String model with JETs model as generator

  6. Design & Implementation of a Mobile Phone Charging System Based on Solar Energy Harvesting

    Qutaiba I. Ali

    2011-01-01

    The ability to harvest energy from the environment represents an important technology area that promises to eliminate wires and battery maintenance for many important applications and permits deploying self powered devices. This paper suggests the use of a solar energy harvester to charge mobile phone devices. In the beginning, a comprehensive overview to the energy harvesting concept and technologies is presented. Then the design procedure of our energy harvester was ...

  7. Determining the charged particle energy losses with usage of transmutation isotopes

    Didik, V A; Skoryatina, E A; Kozlovskij, V V

    2002-01-01

    The method for determining the charged particles energy losses in a solid body, based on the comparison of the transmutation isotopes profiles, formed by irradiation with the particles of various energies, is proposed. The protons energy losses in copper were determined by the described method. The irradiation was performed on a cyclotron by the energies of 8, 10, 12.5, 15.5 and 18 MeV. The obtained results agree well with the published data

  8. A Cost-Effective Electric Vehicle Charging Method Designed For Residential Homes with Renewable Energy

    Lie, T. T.; Liang, Xiuli; Haque, M. H.

    2015-03-01

    Most of the electrical infrastructure in use around the world today is decades old, and may be illsuited to widespread proliferation of personal Electric Vehicles (EVs) whose charging requirements will place increasing strain on grid demand. In order to reduce the pressure on the grid and taking benefits of off peak charging, this paper presents a smart and cost effective EV charging methodology for residential homes equipped with renewable energy resources such as Photovoltaic (PV) panels and battery. The proposed method ensures slower battery degradation and prevents overcharging. The performance of the proposed algorithm is verified by conducting simulation studies utilizing running data of Nissan Altra. From the simulation study results, the algorithm is shown to be effective and feasible which minimizes not only the charging cost but also can shift the charging time from peak value to off-peak time.

  9. Food restriction modulates β-adrenergic-sensitive adenylate cyclase in rat liver during aging

    Adenylate cyclase activities were studied in rat liver during postmaturational aging of male Fischer 344 rats fed ad libitum or restricted to 60% of the ad libitum intake. Catecholamine-stimulated adenylate cyclase activity increased by 200-300% between 6 and 24-27 mo of age in ad libitum-fed rats, whereas in food-restricted rats catecholamine response increased by only 58-84% between 6 and 30 mo. In ad libitum-fed rats, glucagon-stimulated enzyme activity also increased by 40% between 6 and 12 mo and in restricted rats a similar age-related increase was delayed until 18 mo. β-Adrenergic receptor density increased by 50% between 6 and 24 mo in livers from ad libitum-fed but not food-restricted rats and showed a highly significant correlation with maximal isoproterenol-stimulated adenylate cyclase activity over the postmaturational life span. Age-related increases in unstimulated (basal) adenylate cyclase activity and nonreceptor-mediated enzyme activation were retarded by food restriction. The results demonstrate that food restriction diminishes a marked age-related increase in β-adrenergic-sensitive adenylate cyclase activity of rat liver. Alterations of adrenergic-responsive adenylate cyclase with age and the modulatory effects of food restriction appear to be mediated by changes in both receptor and nonreceptor components of adenylate cyclase

  10. Duality of Quasilocal Gravitational Energy and Charges with Non-orthogonal Boundaries

    Kim, S W; Oh, J J; Yee, K H; Kim, Sung-Won; Kim, Won Tae; Oh, John J.; Yee, Ki-Hyuk

    2003-01-01

    We study the duality of quasilocal energy and charges with non-orthogonal boundaries in the (2+1)-dimensional low-energy string theory. Quasilocal quantities shown in the previous work and some new variables arisen from considering the non-orthogonal boundaries as well are presented, and the boost relations between those quantities are discussed. Moreover, we show that the dual properties of quasilocal variables such as quasilocal energy density, momentum densities, surface stress densities, dilaton pressure densities, and Neuve-Schwarz(NS) charge density, are still valid in the moving observer's frame.

  11. Statistical similarity between high energy charged particle fluxes in near-earth space and earthquakes

    Wang, P.; Chang, Z.; Wang, H.; Lu, H.

    2014-05-01

    It has long been noticed that rapid short-term variations of high energy charged particle fluxes in near-Earth space occur more frequently several hours before the main shock of earthquakes. Physicists wish that this observation supply a possible precursor of strong earthquakes. Based on DEMETER data, we investigate statistical behaviors of flux fluctuations for high energy charged particles in near-Earth space. Long-term clustering, scaling, and universality in the temporal occurrence are found. There is high degree statistical similarity between high energy charged particle fluxes in near-Earth space and earthquakes. Thus, the observations of the high energy particle fluxes in near-Earth space may supply a useful tool in the study of earthquakes.

  12. Full charge-density calculation of the surface energy of metals

    Vitos, Levente; Kollár, J..; Skriver, Hans Lomholt

    1994-01-01

    We have calculated the surface energy and the work function of the 4d metals by means of an energy functional based on a self-consistent, spherically symmetric atomic-sphere potential. In this approach the kinetic energy is calculated completely within the atomic-sphere approximation (ASA) by means...... of a spherically symmetrized charge density, while the Coulomb and exchange-correlation contributions are calculated by means of the complete, nonspherically symmetric charge density within nonoverlapping, space-filling Wigner-Seitz cells. The functional is used to assess the convergence and the...... accuracy of the linear-muffin-tin-orbitals (LMTO) method and the ASA in surface calculations. We find that the full charge-density functional improves the agreement with recent full-potential LMTO calculations to a level where the average deviation in surface energy over the 4d series is down to 10%....

  13. Intelligent energy allocation strategy for PHEV charging station using gravitational search algorithm

    Rahman, Imran; Vasant, Pandian M.; Singh, Balbir Singh Mahinder; Abdullah-Al-Wadud, M.

    2014-10-01

    Recent researches towards the use of green technologies to reduce pollution and increase penetration of renewable energy sources in the transportation sector are gaining popularity. The development of the smart grid environment focusing on PHEVs may also heal some of the prevailing grid problems by enabling the implementation of Vehicle-to-Grid (V2G) concept. Intelligent energy management is an important issue which has already drawn much attention to researchers. Most of these works require formulation of mathematical models which extensively use computational intelligence-based optimization techniques to solve many technical problems. Higher penetration of PHEVs require adequate charging infrastructure as well as smart charging strategies. We used Gravitational Search Algorithm (GSA) to intelligently allocate energy to the PHEVs considering constraints such as energy price, remaining battery capacity, and remaining charging time.

  14. Tuning Charge Transfer in Ion-Surface Collisions at Hyperthermal Energies.

    Yao, Yunxi; Giapis, Konstantinos P

    2016-05-18

    Charge exchange in ion-surface collisions may be influenced by surface adsorbates to alter the charge state of the scattered projectiles. We show here that the positive-ion yield, observed during ion scattering on metal surfaces at low incident energies, is greatly enhanced by adsorbing electronegative species onto the surface. Specifically, when beams of N(+) and O(+) ions are scattered off of clean Au surfaces at hyperthermal energies, no positive ions are observed exiting. Partial adsorption of F atoms on the Au surface, however, leads to the appearance of positively charged primary ions scattering off of Au, a direct result of the increase in the Au work function. The inelastic energy losses for positive-ion exits are slightly larger than the corresponding ionization energies of the respective N and O atoms, which suggest that the detected positive ions are formed by surface reionization during the hard collision event. PMID:26879471

  15. An APL program for the distribution of energy deposition by charged particles passing through thin absorbers

    Howell, L. W.

    1985-01-01

    An APL program which numerically evaluates the probability density function (PDF) for the energy deposited in a thin absorber by a charged particle is proposed, with application to the construction, pointing, and control of spacecraft. With this program, the PDF of the restricted energy loss distribution of Watts (1973) is derived, and Vavilov's (1957) distribution is obtained by proper parameter selection. The method is demonstrated with the example of the effect of charged particle induced radiation on the Hubble Space Telescope (HST) pointing accuracy. A Monte Carlo study simulates the photon noise caused by charged particles passing through the photomultiplier tube window, and the stochastic variation of energy loss is introduced into the simulation by generating random energy losses from a power law distribution. The program eliminates annoying loop procedures, and model parameter sensitivity can be studied using the graphical output.

  16. Potential energy curves for neutral and multiply charged carbon monoxide

    Pradeep Kumar; N Sathyamurthy

    2010-01-01

    Potential energy curves of various electronic states of CO+ (0 ≤ ≤ 6) are generated at MRCI/CASSCF level using cc-pvQZ basis set and the results are compared with available experimental and theoretical data.

  17. Parameter-free calculation of charge-changing cross sections at high energy

    Suzuki, Y.; Horiuchi, W.; Terashima, S.; Kanungo, R.; Ameil, F.; Atkinson, J.; Ayyad, Y.; Cortina-Gil, D.; Dillmann, I.; Estradé, A.; Evdokimov, A.; Farinon, F.; Geissel, H.; Guastalla, G.; Janik, R.; Knoebel, R.; Kurcewicz, J.; Litvinov, Yu. A.; Marta, M.; Mostazo, M.; Mukha, I.; Nociforo, C.; Ong, H. J.; Pietri, S.; Prochazka, A.; Scheidenberger, C.; Sitar, B.; Strmen, P.; Takechi, M.; Tanaka, J.; Tanihata, I.; Vargas, J.; Weick, H.; Winfield, J. S.

    2016-07-01

    Charge-changing cross sections at high energies are expected to provide useful information on nuclear charge radii. No reliable theory to calculate the cross section has yet been available. We develop a formula using Glauber and eikonal approximations and test its validity with recent new data on carbon isotopes measured at around 900 A MeV. We first confirm that our theory reproduces the cross sections of 12,13,14C+12C consistently with the known charge radii. Next we show that the cross sections of C-1912 on a proton target are all well reproduced provided the role of neutrons is accounted for. We also discuss the energy dependence of the charge-changing cross sections.

  18. Charged particle density distributions in Au + Au collisions at relativistic heavy-ion collider energies

    Fauad Rami

    2003-05-01

    Charged particle pseudorapidity distributions have been measured in Au + Au collisions using the BRAHMS detector at RHIC. The results are presented as a function of the collision centrality and the center of mass energy. They are compared to the predictions of different parton scattering models and the important role of hard scattering processes at RHIC energies is discussed.

  19. Re-Scaling of Energy in the Stringy Charged Black Hole Solutions using Approximate Symmetries

    Sharif, M.; Waheed, Saira

    2010-01-01

    This paper is devoted to study the energy problem in general relativity using approximate Lie symmetry methods for differential equations. We evaluate second-order approximate symmetries of the geodesic equations for the stringy charged black hole solutions. It is concluded that energy must be re-scaled by some factor in the second-order approximation.

  20. Observation of high iron charge states at low energies in solar energetic particle events

    Guo, Z.; Möbius, E.; Bochsler, P.; Connell, J. J.; Popecki, M. A. [Space Science Center, University of New Hampshire, Durham, NH 03824 (United States); Klecker, B. [Max-Planck-Institut für Extraterrestrische Physik, Postfach 1312, D-85741 Garching (Germany); Kartavykh, Y. Y. [Ioffe Physical-Technical Institute, St-Petersburg 194021 (Russian Federation); Mason, G. M., E-mail: zwm2@unh.edu [Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723 (United States)

    2014-04-10

    The ionic charge states of solar energetic particles (SEPs) provide direct information about the source plasma, the acceleration environment, and their transport. Recent studies report that both gradual and impulsive SEP events show mean iron charge states (Q {sub Fe}) ∼ 10-14 at low energies E ≤ 0.1 MeV nuc{sup –1}, consistent with their origin from typical corona material at temperatures 1-2 MK. Observed increases of (Q {sub Fe}) up to 20 at energies 0.1-0.5 MeV nuc{sup –1} in impulsive SEPs are attributed to stripping during acceleration. However, Q {sub Fe} > 16 is occasionally found in the solar wind, particularly coming from active regions, in contrast to the exclusively reported (Q {sub Fe}) ≤ 14 for low energy SEPs. Here we report results from a survey of all 89 SEP events observed with Advanced Composition Explorer Solar Energetic Particle Ionic Charge Analyzer (SEPICA) in 1998-2000 for iron charge states augmented at low energy with Solar and Heliospheric Observatory CELIAS suprathermal time-of-flight (STOF). Nine SEP events with (Q {sub Fe}) ≥ 14 throughout the entire SEPICA and STOF energy range have been identified. Four of the nine events are impulsive events identified through velocity dispersion that are consistent with source temperatures ≥2 MK up to ∼4 MK. The other five events show evidence of interplanetary acceleration. Four of them involve re-acceleration of impulsive material, whose original energy dependent charge states appear re-distributed to varying extent bringing higher charge states to lower energy. One event, which shows flat but elevated (Q {sub Fe}) ∼ 14.2 over the entire energy range, can be associated with interplanetary acceleration of high temperature material. This event may exemplify a rare situation when a second shock plows through high temperature coronal mass ejection material.

  1. Reactive Power Support of Electrical Vehicle Charging Station Upgraded with Flywheel Energy Storage System

    SUN, BO; Dragicevic, Tomislav; Savaghebi, Mehdi;

    2015-01-01

    influence on future smart transportation network. This paper explores an off-board charging station upgraded with flywheel energy storage system that could provide a reactive power support to the grid utility. A supervisory control scheme based on distributed bus signaling is proposed to coordinate the...... operation of each component in the system. As a result, the charging station could supply the reactive power support to the utility grid without compromising the charging algorithm and preserve the battery’s lifetime. Finally, the real-time simulation results based on dSPACE1006 verifies the proposed...... strategy....

  2. Energy and charge state dependences of transfer ionization to single capture ratio for fast multiply charged ions on helium

    Unal, Ridvan

    The charge state and energy dependences of Transfer Ionization (TI) and Single Capture (SC) processes in collisions of multiply charged ions with He from intermediate to high velocities are investigated using coincident recoil ion momentum spectroscopy. The collision chamber is commissioned on the 15-degree port of a switching magnet, which allows the delivery of a beam with very little impurity. The target was provided from a supersonic He jet with a two-stage collimation. The two-stage, geometrically cooled, supersonic He jet has significantly reduced background contribution to the spectrum compared to a single stage He jet. In the case of a differentially pumped gas cell complex calculations based on assumptions for the correction due to the collisions with the contaminant beam led to corrections, which were up to 50%. The new setup allows one to make a direct separation of contaminant processes in the experimental data using the longitudinal momentum spectra. Furthermore, this correction is much smaller (about 8.8%) yielding better overall precision. The collision systems reported here are 1 MeV/u O(4--8)+ , 0.5--2.5 MeV/u F(4--9)+, 2.0 MeV/u Ti 15,17,18+, 1.6--1.75 MeV/u Cu18,20+ and 0.25--0.5 MeV/u I(15--25)+ ions interacting with helium. We have determined the sTIsSC ratio for high velocity highly charged ions on He at velocities in the range of 6 to 10 au and observed that the ratio is monotonically decreasing with velocity. Furthermore, we see a ratio that follows a q2 dependence up to approximately q = 9. Above q = 9 the experimental values exceed the q2 dependence prediction due to antiscreening. C. D. Lin and H. C. Tseng have performed coupled channel calculations for the energy dependence of TI and SC for F9+ + He and find values slightly higher than our measured values, but with approximately the same energy dependence. The new data, Si, Ti and Cu, go up only to q = 20 and show a smooth monotonically increasing TI/SC ratio. The TI/SC ratio for I (15

  3. Modulation of folding energy landscape by charge–charge interactions: Linking experiments with computational modeling

    Tzul, Franco O.; Schweiker, Katrina L.; Makhatadze, George I.

    2015-01-01

    Quantitative understanding of how individual interactions contribute to the kinetics and thermodynamics of protein folding is critical for deciphering the underlying molecular mechanisms that define the energy folding landscape. We applied a structure-based model that explicitly accounts for the interactions between charges, to folding–unfolding of four different protein pairs: rationally stabilized, via optimization of surface charge–charge interactions, variants, and respective wild types. ...

  4. New heavy charged leptons at future high energy electron-positron colliders

    Almeida Jr., F. M. L.; Coutinho, Y. A.; Simoes, J. A. Martins; Wulck, S.; Vale, M. A. B. do

    2003-01-01

    New heavy charged lepton production and decay signatures at future electron-positron colliders are investigated at $\\sqrt {s}=500$ GeV. The consequences of model dependence for vector singlets and vector doublets are studied. Distributions are calculated including hadronization effects and experimental cuts that suppress the standard model background. The final state leptonic energy distributions are shown to give a very clear signature for heavy charged leptons.

  5. High Energy Ionic Charge State Composition in the October/November 2003 and January 20, 2005 SEP Events

    Labrador, A. W.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C.; von Rosenvinge, T. T.

    2005-01-01

    The ionic charge states of solar energetic particles (SEPs) probe source-material temperatures and acceleration and transport conditions. The MAST instrument on SAMPEX measures SEP ionic charge states at energies greater than ~15 MeV/nuc and at iron energies up to ~90 MeV/nuc using the geomagnetic filter technique. Charge state measurements for large gradual SEP events by MAST and by other experiments suggest that event-to-event variations in the mean charge states of abundant ele...

  6. Measurement of the Atmospheric Muon Charge Ratio at TeV Energies with MINOS

    Adamson, P; Arms, K E; Armstrong, R; Auty, D J; Avvakumov, S; Ayres, D S; Baller, B; Barish, B; Barnes, P D; Barr, G; Barrett, W L; Beall, E; Becker, B R; Belias, A; Bergfeld, T; Bernstein, R H; Bhattacharya, D; Bishai, M; Blake, A; Bock, B; Bock, G J; Böhm, J; Böhnlein, D J; Bogert, D; Border, P M; Bower, C; Buckley-Geer, E; Bungau, C; Cabrera, A; Chapman, J D; Cherdack, D; Childress, S; Choudhary, B C; Cobb, J H; Culling, A J; De Jong, J K; De Santo, A; Dierckxsens, M; Diwan, M V; Dorman, M; Drakoulakos, D; Durkin, T; Erwin, A R; Escobar, C O; Evans, J J; Falk-Harris, E; Feldman, G J; Fields, T H; Ford, R; Frohne, M V; Gallagher, H R; Giurgiu, G A; Godley, A; Gogos, J; Goodman, M C; Gouffon, P; Gran, R; Grashorn, E W; Grossman, N; Grzelak, K; Habig, A; Harris, D; Harris, P G; Hartnell, J; Hartouni, E P; Hatcher, R; Heller, K; Holin, A; Howcroft, C; Hylen, J; Indurthy, D; Irwin, G M; Ishitsuka, M; Jaffe, D E; James, C; Jenner, L; Jensen, D; Joffe-Minor, T; Kafka, T; Kang, H J; Kasahara, S M S; Kim, M S; Koizumi, G; Kopp, S; Kordosky, M; Koskinen, D J; Kotelnikov, S K; Kreymer, A; Kumaratunga, S; Lang, K; Lebedev, A; Lee, R; Ling, J; Liu, J; Litchfield, P J; Litchfield, R P; Lucas, P; Mann, W A; Marchionni, A; Marino, A D; Marshak, M L; Marshall, J S; Mayer, N; McGowan, A M; Meier, J R; Merzon, G I; Messier, M D; Michael, D G; Milburn, R H; Miller, J L; Miller, W H; Mishra, S R; Mislivec, A; Miyagawa, P S; Moore, C D; Morfin, J; Mualem, L; Mufson, S; Murgia, S; Musser, J; Naples, D; Nelson, J K; Newman, H B; Nichol, R J; Nicholls, T C; Ochoa-Ricoux, J P; Oliver, W P; Osiecki, T; Ospanov, R; Paley, J; Paolone, V; Para, A; Patzak, T; Pavlovic, Z; Pearce, G F; Peck, C W; Peterson, E A; Petyt, D A; Ping, H; Piteira, R; Pittam, R; Plunkett, R K; Rahman, D; Rameika, R A; Raufer, T M; Rebel, B; Reichenbacher, J; Reyna, D E; Rosenfeld, C; Rubin, H A; Ruddick, K; Ryabov, V A; Saakyan, R; Sanchez, M C; Saoulidou, N; Schneps, J; Schreiner, P; Semenov, V K; Seun, S M; Shanahan, P; Smart, W; Smirnitsky, V; Smith, C; Sousa, A; Speakman, B; Stamoulis, P; Symes, P A; Tagg, N; Talaga, R L; Tetteh-Lartey, E; Thomas, J; Thompson, J; Thomson, M A; Thron, J L; Tinti, G; Trostin, I; Tsarev, V A; Tzanakos, G; Urheim, J; Vahle, P; Velissaris, C; Verebryusov, V; Viren, B; Ward, C P; Ward, D R; Watabe, M; Weber, A; Webb, R C; Wehmann, A; West, N; White, C; Wojcicki, S G; Wright, D M; Wu, Q K; Yang, T; Yumiceva, F X; Zheng, H; Zois, M; Zwaska, R

    2007-01-01

    The 5.4 kton MINOS far detector has been taking charge-separated cosmic ray muon data since the beginning of August, 2003 at a depth of 2070 meters-water-equivalent in the Soudan Underground Laboratory, Minnesota, USA. The data with both forward and reversed magnetic field running configurations were combined to minimize systematic errors in the determination of the underground muon charge ratio. When averaged, two independent analyses find the charge ratio underground to be 1.374 +/- 0.004 (stat.) +0.012 -0.010(sys.). Using the map of the Soudan rock overburden, the muon momenta as measured underground were projected to the corresponding values at the surface in the energy range 1-7 TeV. Within this range of energies at the surface, the MINOS data are consistent with the charge ratio being energy independent at the two standard deviation level. When the MINOS results are compared with measurements at lower energies, a clear rise in the charge ratio in the energy range 0.3 -- 1.0 TeV is apparent. A qualitativ...

  7. Energy dependence of mass, charge, isotopic, and energy distributions in neutron-induced fission of 235U and 239Pu

    Pasca, H.; Andreev, A. V.; Adamian, G. G.; Antonenko, N. V.; Kim, Y.

    2016-05-01

    The mass, charge, isotopic, and kinetic-energy distributions of fission fragments are studied within an improved scission-point statistical model in the reactions 235U+n and 239Pu+n at different energies of the incident neutron. The charge and mass distributions of the electromagnetic- and neutron-induced fission of 214,218Ra, 230,232,238U are also shown. The available experimental data are well reproduced and the energy-dependencies of the observable characteristics of fission are predicted for future experiments.

  8. Energy straggling determination for charged particles in thick targets

    Energy straggling is reported for deuterons in carbon and protons in silicon, and the data obtained is compared with predictions of Bohr and Bethe. The experimental method used is based on a reaction resonance widening, observed at backward angles in the thick targets. The incident energy determines the depth at which the resonant scattering occurs and the energy straggling can be measured from the backscattering spectra. The data obtained for the energy straggling of deuterons are approximately two times bigger than those predicted by Bohr's theory; nevertheless, the values found for the energy straggling of protons in silicon are in agreement with the values predicted by the aforesaid theory. This disagreement was explained by the fact that carbon targets used were amorphous and porous, in contrast with those of cristal silicon, (it is an experimental fact that porous materials are expected to give higher stragglings than non-porous ones). Thus, the method reviewed in this work is valid, but the porosity effects should be taken into account in comparing results among materials with different densities. (author)

  9. Excitation energy transfer and charge separation in photosystem II membranes revisited.

    Broess, Koen; Trinkunas, Gediminas; van der Weij-de Wit, Chantal D; Dekker, Jan P; van Hoek, Arie; van Amerongen, Herbert

    2006-11-15

    We have performed time-resolved fluorescence measurements on photosystem II (PSII) containing membranes (BBY particles) from spinach with open reaction centers. The decay kinetics can be fitted with two main decay components with an average decay time of 150 ps. Comparison with recent kinetic exciton annihilation data on the major light-harvesting complex of PSII (LHCII) suggests that excitation diffusion within the antenna contributes significantly to the overall charge separation time in PSII, which disagrees with previously proposed trap-limited models. To establish to which extent excitation diffusion contributes to the overall charge separation time, we propose a simple coarse-grained method, based on the supramolecular organization of PSII and LHCII in grana membranes, to model the energy migration and charge separation processes in PSII simultaneously in a transparent way. All simulations have in common that the charge separation is fast and nearly irreversible, corresponding to a significant drop in free energy upon primary charge separation, and that in PSII membranes energy migration imposes a larger kinetic barrier for the overall process than primary charge separation. PMID:16861268

  10. Charge state distributions and charge-changing cross sections of heavy ions in the energy range up to 10 MeV/u

    Charge state distributions and charge-changing cross sections have been measured for heavy ions with atomic numbers between 18 and 92, in charge states from +9 to +68, and at energies in the range from 0.2 to 10 MeV/u using various gaseous and solid target materials. The experimental cross sections are compared with the theory of Bohr and Lindhard. The accuracy of predictions by means of known empirical formulae for average equilibrium charge states is briefly discussed. (author)

  11. Ab initio calculation of the formation energy of charged vacancies in germanium

    Density functional theory (DFT) with local density approximation (LDA) has been used to calculate the formation energy (Ef) of the neutral and charged vacancies in germanium single crystal. The standard (four valence electrons) and harder (which treat the semicore 3d states of Ge as valence) projector augmented wave (PAW) potentials were used. Additionally, the effect of including on-site Coulomb interaction, U, for Ge semicore d states within the LDA+U approach was investigated. The LDA+U method improves the LDA band gap which allows investigating the dependence of formation energy of charged vacancies on Fermi level position in the band gap. It was shown that the calculated formation energies of the neutral and charged vacancies are in good agreement with published experimental data

  12. Charging-free electrochemical system for harvesting low-grade thermal energy

    Yang, Yuan; Lee, Seok Woo; Ghasemi, Hadi; Loomis, James; Li, Xiaobo; Kraemer, Daniel; Zheng, Guangyuan; Cui, Yi; Chen, Gang

    2014-01-01

    Tremendous low-grade heat is stored in industrial processes and the environment. Efficient and low-cost utilization of the low-grade heat is critical to imminent energy and environmental challenges. Here, a rechargeable electrochemical cell (battery) is used to harvest such thermal energy because its voltage changes significantly with temperature. Moreover, by carefully tuning the composition of electrodes, the charging process is purely powered by thermal energy and no electricity is require...

  13. Charge transfer activation energy for alkali atoms on Re and Ta

    Gładyszewski, Longin

    1993-09-01

    Ion and atom desorption energies for five alkali metals on Re and Ta were determined using the ion thermal emission noise method. The activation energies for the charge transfer process in the adsorbed state were calculated using a special energetic balance equation, which describes the surface ionization and thermal desorption effect. Energies for desorption of Li, Na, K, Rb and Cs from Re and Ta surfaces were determined by measuring the time autocorrelation function of the ion thermoemission current fluctuations.

  14. Charge and Mass Effects on Low Energy Ion Channeling in Carbon Nanotubes

    LI Yong; ZHENG Li-Ping; ZHANG Wei; XV Zi-Jian; REN Cui-Lan; HUAI Ping; ZHU Zhi-Yuan

    2011-01-01

    @@ Channeling phenomena of He, Ne, Ar and Kr ions at energy (200-5000eV) in single-wall carbon nanotubes (SWCNTs) are investigated by molecular dynamics simulation with analytical potentials.The critical angles for the particles to be channeled in an SWCNT are analyzed.In the incident energy range of 200-5000 eV, it is found that the ion energy dependence of the critical angle obeys an improved Lindhard equation which is closely related to the ratio of nuclear charge number to atomic mass Z/M.The critical angle for different types of ions channeling in SWCNTs is determined by both the atomic nuclear charge and mass.%Channeling phenomena of He, Ne, Ar and Kr ions at energy (200-5000eV) in single-wall carbon nanotubes (SWCNTs) are investigated by molecular dynamics simulation with analytical potentials. The critical angles for the particles to be channeled in an SWCNT are analyzed. In the incident energy range of 200-5000eV, it is found that the ion energy dependence of the critical angle obeys an improved Lindhard equation which is closely related to the ratio of nuclear charge number to atomic mass Z/M. The critical angle for different types of ions channeling in SWCNTs is determined by both the atomic nuclear charge and mass.

  15. Direct observation of Space Charge Dynamics by picosecond Low Energy Electron Scattering

    Cirelli, C; Hengsberger, M.; Dolocan, A; Over, H.; Osterwalder, J; Greber, T.

    2008-01-01

    The electric field governing the dynamics of space charge produced by high intensity femtosecond laser pulses focused on a copper surface is investigated by time-resolved low-energy-electron-scattering. The pump-probe experiment has a measured temporal resolution of better than 35 ps at 55 eV probe electron energy. The probe electron acceleration due to space charge is reproduced within a 3-dimensional non-relativistic model, which determines an effective number of electrons in the space char...

  16. Systematic study of individual charge-changing cross sections of intermediate-energy secondary beams

    Highlights: • Precision total and partial charge-changing cross section measurements of medium-mass nuclides were performed. • Systematic reaction data of intermediate-energy heavy-ion beams were obtained. • A significant odd-even effect is found in the partial charge-changing cross sections. -- Abstract: Charge-changing interactions of stable and unstable medium-mass nuclides have been systematically investigated at intermediate energies. Secondary beams ranging from Ar to Ge isotopes produced by projectile fragmentation of 56Fe and 70Ge were irradiated onto a carbon target, and their total and partial charge-changing cross sections were precisely measured. A clear odd–even effect found in the partial charge-changing cross sections monotonically varies as a function of the Z/N ratio among the isotopes, and grows toward the neutron-deficient side. The total charge-changing cross sections are sensitive to the Z number of nuclides, and tend to gradually increase toward the neutron-deficient side in some isotopes

  17. Synthetic system mimicking the energy transfer and charge separation of natural photosynthesis

    Gust, D.; Moore, T.A.

    1985-05-01

    A synthetic molecular triad consisting of a porphyrin P linked to both a quinone Q and a carotenoid polyene C has been prepared as a mimic of natural photosynthesis for solar energy conversion purposes. Laser flash excitation of the porphyrin moiety yields a charge-separated state Csup(+.)-P-Qsup(-.) within 100 ps with a quantum yield of more than 0.25. This charge-separated state has a lifetime on the microsecond time scale in suitable solvents. The triad also models photosynthetic antenna function and photoprotection from singlet oxygen damge. The successful biomimicry of photosynthetic charge separation is in part the result of multistep electron transfers which rapidly separate the charges and leave the system at high potential, but with a considerable barrier to recombination.

  18. Benchmark of Space Charge Simulations and Comparison with Experimental Results for High Intensity, Low Energy Accelerators

    Cousineau, Sarah M

    2005-01-01

    Space charge effects are a major contributor to beam halo and emittance growth leading to beam loss in high intensity, low energy accelerators. As future accelerators strive towards unprecedented levels of beam intensity and beam loss control, a more comprehensive understanding of space charge effects is required. A wealth of simulation tools have been developed for modeling beams in linacs and rings, and with the growing availability of high-speed computing systems, computationally expensive problems that were inconceivable a decade ago are now being handled with relative ease. This has opened the field for realistic simulations of space charge effects, including detailed benchmarks with experimental data. A great deal of effort is being focused in this direction, and several recent benchmark studies have produced remarkably successful results. This paper reviews the achievements in space charge benchmarking in the last few years, and discusses the challenges that remain.

  19. Fractionally Charged Zero-Energy Single-Particle Excitations in a Driven Fermi Sea

    Moskalets, Michael

    2016-07-01

    A voltage pulse of a Lorentzian shape carrying half of the flux quantum excites out of a zero-temperature Fermi sea an electron in a mixed state, which looks like a quasiparticle with an effectively fractional charge e /2 . A prominent feature of such an excitation is a narrow peak in the energy distribution function lying exactly at the Fermi energy μ . Another spectacular feature is that the distribution function has symmetric tails around μ , which results in a zero-energy excitation. This sounds improbable since at zero temperature all available states below μ are fully occupied. The resolution lies in the fact that such a voltage pulse also excites electron-hole pairs, which free some space below μ and thus allow a zero-energy quasiparticle to exist. I discuss also how to address separately electron-hole pairs and a fractionally charged zero-energy excitation in an experiment.

  20. Measurements of charge distributions of the fragments in the low energy fission reaction

    The measurement for charge distributions of fragments in spontaneous fission 252Cf has been performed by using a unique style of detector setup consisting of a typical grid ionization chamber and a ΔΕ−Ε particle telescope, in which a thin grid ionization chamber served as the ΔΕ-section and the E-section was an Au–Si surface barrier detector. The typical physical quantities of fragments, such as mass number and kinetic energies as well as the deposition in the gas ΔΕ detector and E detector were derived from the coincident measurement data. The charge distributions of the light fragments for the fixed mass number A2⁎ and total kinetic energy (TKE) were obtained by the least-squares fits for the response functions of the ΔΕ detector with multi-Gaussian functions representing the different elements. The results of the charge distributions for some typical fragments are shown in this article which indicates that this detection setup has the charge distribution capability of Ζ:ΔΖ>40:1. The experimental method developed in this work for determining the charge distributions of fragments is expected to be employed in the neutron induced fissions of 232Th and 238U or other low energy fission reactions.

  1. Energy dependence of muon charge ratio for incident momentum range < 1 GeV/c

    Full text: The charge ratio of the atmospheric muons is a quantity sensitive to hadronic interactions of cosmic rays and to the influence of the geomagnetic field. Experimental information is of current interest for tuning models used for the calculation of atmospheric neutrino fluxes. We are performing measurements of the charge ratio based on the observation of the lifetime of the muons stopped in the absorber layers (aluminum support) of the detector WILLI, mounted in a rotatable frame and installed at IFIN-HH Bucharest (vertical geomagnetic cut-off rigidity of 5.6 GV). Our method to determine the muon charge ratio by measuring the lifetime of muons stopped in the matter, overcomes the uncertainties appearing in measurements based on magnetic spectrometers, which are affected by systematic effects at low muon energies, due to problems in the particle and trajectory identification. The results obtained with the rotatable WILLI detector, inclined at 45 angle (i.e. a mean zenith angle of detected muons of 35 angle), relevant to the atmospheric neutrino anomaly, show a pronounced east-west effect. The energy dependence of the muon charge ratio indicates an increasing asymmetry of the muon charge ratio with decreasing incident energy. (author)

  2. Activation of the Pacidamycin PacL Adenylation Domain by MbtH-Like Proteins†

    Zhang, Wenjun; Heemstra, John R.; Walsh, Christopher T.; Imker, Heidi J.

    2010-01-01

    Nonribosomal peptide synthetase (NRPS) assembly lines are major avenues for the biosynthesis of a vast array of peptidyl natural products. Several hundred bacterial NRPS gene clusters contain a small (~70 residue) protein belonging to the MbtH family for which no function has been defined. Here we show that two strictly conserved Trp residues in MbtH-like proteins contribute to stimulation of amino acid adenylation in some NRPS modules. We also demonstrate that adenylation can be stimulated n...

  3. Oligo-2',5'-adenylate synthetase activity in peripheral blood mononuclear leukocytes in various diseases.

    Fujii, N; Kotake, S.; Hirose, S; Ohno, S; Yasuda, I.; Sagawa, A; Ishikawa, K.; Minagawa, T

    1984-01-01

    Interferon induces oligo-2',5'-adenylate synthetase in cells. In various diseases, interferon was detectable in the circulation or was produced spontaneously from peripheral blood mononuclear leukocytes. The oligo-2',5'-adenylate synthetase activity in peripheral blood mononuclear leukocytes was examined in various diseases, including systemic lupus erythematosus, sarcoidosis, Vogt-Koyanagi-Harada disease, and Behcet's disease. The activity of this enzyme was significantly increased in system...

  4. Aprataxin resolves adenylated RNA–DNA junctions to maintain genome integrity

    Tumbale, Percy [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States). Lab. of Structural Biology; Williams, Jessica S. [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States). Lab. of Structural Biology; Schellenberg, Matthew J. [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States). Lab. of Structural Biology; Kunkel, Thomas A. [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States). Lab. of Structural Biology and Lab. of Molecular Genetics; Williams, R. Scott [National Inst. of Environmental Health Sciences, Research Triangle Park, NC (United States). Lab. of Structural Biology and Lab. Molecular Genetics

    2013-12-22

    Faithful maintenance and propagation of eukaryotic genomes is ensured by three-step DNA ligation reactions used by ATP-dependent DNA ligases. Paradoxically, when DNA ligases encounter nicked DNA structures with abnormal DNA termini, DNA ligase catalytic activity can generate and/or exacerbate DNA damage through abortive ligation that produces chemically adducted, toxic 5'-adenylated (5'-AMP) DNA lesions. Aprataxin (APTX) reverses DNA adenylation but the context for deadenylation repair is unclear. Here we examine the importance of APTX to RNase-H2-dependent excision repair (RER) of a lesion that is very frequently introduced into DNA, a ribonucleotide. We show that ligases generate adenylated 5' ends containing a ribose characteristic of RNase H2 incision. APTX efficiently repairs adenylated RNA–DNA, and acting in an RNA–DNA damage response (RDDR), promotes cellular survival and prevents S-phase checkpoint activation in budding yeast undergoing RER. Structure–function studies of human APTX–RNA–DNA–AMP–Zn complexes define a mechanism for detecting and reversing adenylation at RNA–DNA junctions. This involves A-form RNA binding, proper protein folding and conformational changes, all of which are affected by heritable APTX mutations in ataxia with oculomotor apraxia 1. Together, these results indicate that accumulation of adenylated RNA–DNA may contribute to neurological disease.

  5. Optimization of ATP synthase function in mitochondria and chloroplasts via the adenylate kinase equilibrium

    Abir U Igamberdiev

    2015-01-01

    Full Text Available The bulk of ATP synthesis in plants is performed by ATP synthase, the main bioenergetics engine of cells, operating both in mitochondria and in chloroplasts. The reaction mechanism of ATP synthase has been studied in detail for over half a century; however, its optimal performance depends also on the steady delivery of ATP synthase substrates and the removal of its products. For mitochondrial ATP synthase, we analyze here the provision of stable conditions for (i the supply of ADP and Mg2+, supported by adenylate kinase (AK equilibrium in the intermembrane space, (ii the supply of phosphate via membrane transporter in symport with H+, and (iii the conditions of outflow of ATP by adenylate transporter carrying out the exchange of free adenylates. We also show that, in chloroplasts, AK equilibrates adenylates and governs Mg2+ contents in the stroma, optimizing ATP synthase and Calvin cycle operation, and affecting the import of inorganic phosphate in exchange with triose phosphates. It is argued that chemiosmosis is not the sole component of ATP synthase performance, which also depends on AK-mediated equilibrium of adenylates and Mg2+, adenylate transport and phosphate release and supply.

  6. Charge, quantum state, and energy distributions of impurities released in plasma-wall interaction processes

    Conventional wisdom has it that total sputtering yields correlate with high Z-impurity levels found in fusion plasmas. The charge, quantum states and energy distributions of sputtered atoms have been virtually ignored in these considerations. Impurity transport from the wall or limiter to the plasma is, however, strongly influenced by these factors which may play a crucial role in determining impurity levels in the deeper plasma regions. Preliminary calculations have shown that positively charged impurities would most likely be redeposited on their surfaces of origin. The conditions leading to charged or excited state atoms emission and the energy distributions of such species are reviewed. Techniques for measuring these quantities are discussed and the need for a wider data base in this field is pointed out

  7. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

    2014-02-15

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup −} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  8. The role of electron capture and energy exchange of positively charged particles passing through matter

    Ulmer, W

    2011-01-01

    The conventional treatment of the Bethe-Bloch equation for protons accounts for electron capture at the end of the projectile track by the small Barkas correction. This is only a possible way for protons, whereas for light and heavier charged nuclei the exchange of energy and charge along the track has to be accounted for by regarding the projectile charge q as a function of the residual energy. This leads to a significant modification of the Bethe-Bloch equation, otherwise the range in a medium is incorrectly determined. The LET in the Bragg peak domain and distal end is significantly influenced by the electron capture. A rather significant result is that in the domain of the Bragg peak the superiority of carbon ions is reduced compared to protons.

  9. Damaging impacts of energetic charge particles on materials in plasma energy explosive events

    Deng Bai-Quan; Peng Li-Lin; Yan Jian-Cheng; Luo Zheng-Ming; Chen Zhi

    2006-01-01

    To provide some reference data for estimation of the erosion rates and lifetimes of some candidate plasma facing component (PF3 materials in the plasma stored energy explosive events (PSEEE), this paper calculates the sputtering yields of Mo, W and deuterium saturated Li surface bombarded by energetic charged particles by a new sputtering physics description method based on bipartition model of charge particle transport theory. The comparisons with Monte Carlo data of TRIM code and experimental results are made. The dependences of maximum energy deposition,particle and energy reflection coefficients on the incident energy of energetic runaway electrons impinging on the different material surfaces are also calculated. Results may be useful for estimating the lifetime of PFC and analysing the impurity contamination extent, especially in the PSEEE for high power density and with high plasma current fusion reactor.

  10. Proposal of the Electrically Charged Stellar Black Holes as Accelerators of Ultra High Energy Cosmic Rays

    Soto-Manriquez, Jose

    2016-01-01

    A new mechanism for the acceleration of ultra high energy cosmic rays (UHECR) is presented here. It is based on the tunnel-ionization of neutral atoms approaching electrically charged stellar black holes and on the repulsion of the resulting positively charged atomic part by huge, long-range electric fields. Energies above $10^{18}$ eV for these particles are calculated in a simple way by means of this single-shot, all-electrical model. When this acceleration mechanism is combined with the supernova explosions in the galactic halo of the massive runaway stars expelled from the galactic disk, this model predicts nearly the correct values of the measured top energy of the UHECRs and their flux in a specified EeV energy range. It also explains the near isotropy of the arrivals of these energetic particles to Earth, as has been recently measured by the Auger Observatory.

  11. Elastic, excitation, ionization and charge transfer cross sections of current interest in fusion energy research

    Schultz, D.R.; Krstic, P.S. [Oak Ridge National Lab. TN (United States). Physics Div.

    1997-01-01

    Due to the present interest in modeling and diagnosing the edge and divertor plasma regions in magnetically confined fusion devices, we have sought to provide new calculations regarding the elastic, excitation, ionization, and charge transfer cross sections in collisions among relevant ions, neutrals, and isotopes in the low-to intermediate-energy regime. We summarize here some of our recent work. (author)

  12. Pseudo Open Drain IO Standards Based Energy Efficient Solar Charge Sensor Design on 20nm FPGA

    Kalia, K; Pandey, B; Nanda, K;

    2015-01-01

    In this paper an approach is made to design Pseudo open drain IO standards Based Energy efficient solar charge sensor design on 20nm and 28nm technology. We have used LVCMOS18, POD10, POD10_DCI and POD12 I/O standard. In this design, we have taken two main parameters for analysis that are frequen...

  13. Charge transfer and structured vibrational distributions in H++CH4 low-energy collisions

    Inelastic and charge transfer collisions of protons with methane molecules have been investigated in a perpendicular-plane crossed beam experiment via the detection of the scattered protons and H atoms, respectively. Time-of-flight analysis of the protons and H atoms at scattering angles 00≤θ≤100 and collision energies 10≤E≤30 eV provided information on internal energy distributions of the CH4 and CH+4 products. Excitation of the n(ν1 ,ν3) +m (ν2 ,ν4) type vibrations, with n,m = 0, 1, 2,xxxwas found to be the most probable assignment of the observed structured energy distributions of CH4 (1 A1 ) at θ≤40. At θ>40, the energy transfer increases steeply up to the dissociation limit while the vibrational structure was no longer resolved. In the case of charge transfer, the observed narrow internal energy distributions corresponding to a most probable average internal energy of CH+4 of about 0.95 eV was centered at the recombination energy of the proton indicative of quasiresonant charge transfer. In addition, fragmentation of CH+4 formed in charge transfer collisions of H+ with CH4 was investigated in an independent experiment using mass spectrometric analysis to identify the individual fragment species. The relative intensities of the parent and fragment ions (i.e., of CH+4, CH+3, and CH+2) were found to be in good agreement with the known values of the appearance potentials of the fragment ions and the distribution of the CH+4 internal energy as obtained from the differential cross sections

  14. A Schwinger-type variational principle for charge exchange at arbitrary energies

    An overview of difficulties encountered in charge exchange collision theory is presented. We emphasize problems in the most critical intermediate energy region where, as yet, no adequate method is available. A Schwinger-type variational principle, which is established at arbitrary energies, appears to exhibit many advantages over existing theories. It successfully connects the leading second Born approximation with the efficient L2-expansion methods. (orig.)

  15. Charge state and energy loss of relativistic heavy ions in matter

    Relativistic heavy-ion collisions of few-electron projectiles ranging from argon up to uranium have been investigated in solid and gaseous media. Electron-loss and electron-capture cross sections, charge-state distributions, as well as energy loss and energy deposition have been measured and are compared with theoretical predictions. Especially fully-ionized heavy projectiles represent a unique possibility to test atomic-collision theories. (orig.)

  16. High-resolving electrostatic charged particles energy analyzer with fine tuning for space investigations

    The paper presents results of numerical calculations of a high-resolving electrostatic energy analyzer, based on a bounded cylindrical field, for investigations of flows of charged particles in space. The analyzer possesses with ability of fine tuning of focusing characteristics, using an additional tuning potential, applied to one of electrodes. A combination of high energy resolution ability with high transmission, simple design and compactness makes this instrument very promising for space technologies

  17. Azimuthally-integrated HBT parameters for charged pions in nuclear-nuclear collisions versus initial energy

    Okorokov, V A

    2014-01-01

    In the paper energy dependence of space-time extent of charged pion source is studied for various ion collisions for all experimentally available energies. There are no sharp changing of femtoscopy parameter values with increasing of $\\sqrt{s_{NN}}$ in domain of collision energies $\\sqrt{s_{NN}} \\geq 5$ GeV. Energy dependence of estimations for emission duration is almost flat for all energy domain under study within large error bars. Analytic function is suggested for smooth approximation of energy dependence of main HBT parameters. Fit curves demonstrate reasonable agreement with experimental data for most femtoscopy parameters in energy domain $\\sqrt{s_{NN}} \\geq 5$ GeV. Estimations of femtoscopy observables are obtained for energies of the LHC and FCC project.

  18. Emittance growth in displaced, space-charge-dominated beams with energy spread

    Conversion of transverse energy associated with the coherent motion of displaced beams into thermal energy, and thus emittance growth, has been predicted theoretically by a number of authors. Here, the authors show, using 2-D particle-in-cell simulations, that emittance growth is inhibited for tune depressed beams, if the energy spread of the beam is not too large. Further, using a uniform density model to calculate the space charge field of the beam, they numerically determine the criteria for emittance growth as a function of tune depression, energy spread, and beam displacement over a wide range of parameters. A theoretical interpretation of their results is presented

  19. Total Energy of Charged Black Holes in Einstein-Maxwell-Dilaton-Axion Theory

    Murat Korunur

    2012-01-01

    Full Text Available We focus on the energy content (including matter and fields of the Møller energy-momentum complex in the framework of Einstein-Maxwell-Dilaton-Axion (EMDA theory using teleparallel gravity. We perform the required calculations for some specific charged black hole models, and we find that total energy distributions associated with asymptotically flat black holes are proportional to the gravitational mass. On the other hand, we see that the energy of the asymptotically nonflat black holes diverge in a limiting case.

  20. Energy loss straggling of heavy charged particles in thick silicon absorbers

    The energy loss straggling of heavy charged particles with relatively high energies passing through thick uniform Si detectors (1.0mm-9.2mm) has been studied in a wide range of the ratio ΔE/E0 where ΔE is the energy loss and E0 is the initial energy of the incident particles. The experimental results are compared with those predicted by straggling theories. It suggests that the measured distributions are in good agreement with those predicted from the Bohr's or Livingston-Bethe's theories when ΔE/E00>0.3. (author)

  1. Enhanced charge efficiency and reduced energy use in capacitive deionization by increasing the discharge voltage.

    Kim, T; Dykstra, J E; Porada, S; van der Wal, A; Yoon, J; Biesheuvel, P M

    2015-05-15

    Capacitive deionization (CDI) is an electrochemical method for water desalination using porous carbon electrodes. A key parameter in CDI is the charge efficiency, Λ, which is the ratio of salt adsorption over charge in a CDI-cycle. Values for Λ in CDI are typically around 0.5-0.8, significantly less than the theoretical maximum of unity, due to the fact that not only counterions are adsorbed into the pores of the carbon electrodes, but at the same time coions are released. To enhance Λ, ion-exchange membranes (IEMs) can be implemented. With membranes, Λ can be close to unity because the membranes only allow passage for the counterions. Enhancing the value of Λ is advantageous as this implies a lower electrical current and (at a fixed charging voltage) a reduced energy use. We demonstrate how, without the need to include IEMs, the charge efficiency can be increased to values close to the theoretical maximum of unity, by increasing the cell voltage during discharge, with only a small loss of salt adsorption capacity per cycle. In separate constant-current CDI experiments, where after some time the effluent salt concentration reaches a stable value, this value is reached earlier with increased discharge voltage. We compare the experimental results with predictions of porous electrode theory which includes an equilibrium Donnan electrical double layer model for salt adsorption in carbon micropores. Our results highlight the potential of modified operational schemes in CDI to increase charge efficiency and reduce energy use of water desalination. PMID:25278271

  2. Charge-changing reactions of secondary fragments produced in high-energy heavy ion collisions

    The authors have begun a program to measure charge changing cross sections of projectile fragments using a quite different technique that is capable of much higher data acquisition rates. The primary beam impinges on a stack of 50 Lucite strips having an average thickness of 3.17 mm, emitting Cerenkov light as its passes through them. Since at a given velocity the intensity of light is proportional to Z2, where Z is the charge of the particle, a fragmentation reaction in a particular strip will be registered as a drop in the light output from that and subsequent strips. The authors use total internal reflection to transport the light to photomultiplier tubes so that there is no wrapping between the strips. Since the energy threshold of the device is approx.1.1 GeV/nucleon, low energy target fragments will not contribute to the signal, a distinct advantage over similar schemes using energy loss to measure the fragment charge. The resolution of the individual strips is typically 0.58 charge units, full width at half maximum, allowing reactions to be well localized even for single unit charge changes. In addition to the C detectors, scintillators and Si(Li) detectors were used to measure precisely the position and charge of the incoming beam particle. The authors have taken data using two beams, 56Fe and 40Ar, at 1.88 and 1.82 GeV/nucleon respectively, and two trigger modes, a free trigger to measure the reaction rate of the incoming beam and an inelastic trigger in which a reaction was required to occur in one of the first 14 C detectors. A total of 909,000 56Fe interactions and 460,000 40Ar interactions have been analyzed so far

  3. Local vs. non-local energy loss of low energy ions: Influence of charge exchange processes in close collisions

    Primetzhofer, D., E-mail: daniel.primetzhofer@physics.uu.se [Ion Physics, Department of Physics and Astronomy, Ångström Laboratory, Uppsala University, Box 516, S-751 20 Uppsala (Sweden); Goebl, D.; Bauer, P. [Institut für Experimentalphysik, Johannes Kepler Universität Linz, A-4040 Linz (Austria)

    2013-12-15

    We investigate the contribution of charge exchange processes in close collisions between projectile and target atoms to the electronic energy loss of low energy ions. We measure the energy loss of slow hydrogen and He ions in ultrathin Al films through which the ions are transmitted before and after backscattering by the atoms of a Ta substrate. The individual contributions to the energy loss are analyzed. The roles of thresholds for reionization and of scattering kinematics as key parameters for the coupling between elastic and inelastic losses are discussed. The implications of the obtained results for different experimental approaches to deduce stopping cross sections are outlined.

  4. Production of a high energy beam of multiply charged Cn+60 ions

    For the first time fullerene ions have been accelerated to high energy (14-50 MeV). Negative ions of C-60 were produced in the ion source with a Cs gun and injected into the tandem accelerator. The change of charge from negative to positive was achieved in a N2 gas cell at the high voltage terminal before the second acceleration. To identify the accelerated molecular ions, the injected beam was pulsed, and time of flight measurements were performed. Unambiguous mass and charge assignments were obtained

  5. Twin boundary energy and characterization of charge redistribution near the twin boundaries of cupperate superconductors

    Highlights: • Ab initio simulation for twin boundary energy in YBCO system for the 1st time. • Study of the twin boundary energy variation versus the inserted strain. • Proportionality of twin lamella width by the inserted strain. • Local charge transfer and charge redistribution on the twin planes. • Total DOSs for the twined system at Fermi level is higher than the untwined one. • This explain the effect of twin boundaries in agreement with experimental data. - Abstract: Ab-initio calculations under general gradient approximation have been employed for the first time to find out twin boundary energy, γ, in twined YBCO systems. Despite a vast discrepancy in reported experimental values, our results show that the γ value falls in the range of 40–85 mJ/m2. On the other hand, functional form of γ versus inserted strains shows that the mean value for the twin width lamella would tend to approach zero as the strain goes to zero. We have also investigated the local charge transfer and the modification of the electronic states of the basal and twin planes in YBCO, because the charge redistribution at interfaces can modify transport across the grains considerably and determine the applicability of high-Tc superconductors in the electronic applications. The total density of electronic states at the Fermi level for the twined system is enhanced in comparison with the untwined one. Our results explain the influence of twin boundaries in superconductive properties of YBCO, in experimental situations

  6. Regional differences in system usage charges. Impediment to a fair energy transition?

    The conversion of the German electricity supply system to production from renewable resources under the national energy transition policy is making it necessary to expand and restructure the distribution networks. Based on the expansion goals of the federal government, expectations are that thinly populated regions with low conflict potential will see a continued growth in distributed generation. This will increase the geographic asymmetry that exists between the production of renewable energy in rural, peripheral regions and its consumption predominantly in urban regions, thus enlarging the regional differences in system usage charges seen already today. The geographic disparity between production and consumption may grow larger still with the continuing installation of new and repowering of existing renewable energy plants. Of the possibilities discussed so far for reforming the scheme of charges, some would only have a weak impact, while others would even exacerbate the problem. The solution proposed in the present article takes account of the costs incurred through upstream supply networks in accordance with Article 14 Section 1 Sentence 1 of the Ordinance on System Usage Charges. In effect it leads to an allocation of costs according to the user-pays principle, thus protecting consumers connected to rural distribution networks against an undue cost burden and charging a fair share of the costs to consumers in urban and industrial distribution networks.

  7. Interaction of low-energy highly charged ions with matter; Wechselwirkung niederenergetischer hochgeladener Ionen mit Materie

    Ginzel, Rainer

    2010-06-09

    The thesis presented herein deals with experimental studies of the interaction between highly charged ions and neutral matter at low collision energies. The energy range investigated is of great interest for the understanding of both charge exchange reactions between ions comprising the solar wind and various astrophysical gases, as well as the creation of near-surface nanostructures. Over the course of this thesis an experimental setup was constructed, capable of reducing the kinetic energy of incoming ions by two orders of magnitude and finally focussing the decelerated ion beam onto a solid or gaseous target. A coincidence method was employed for the simultaneous detection of photons emitted during the charge exchange process together with the corresponding projectile ions. In this manner, it was possible to separate reaction channels, whose superposition presumably propagated large uncertainties and systematic errors in previous measurements. This work has unveiled unexpectedly strong contributions of slow radiative decay channels and clear evidence of previously only postulated decay processes in charge exchange-induced X-ray spectra. (orig.)

  8. Calculation of Coulomb energies for uniform charge distributions of arbitrary shape

    Three distinct surface-integral formulas are derived for calculating the Coulomb energies of uniform charge distributions of arbitrary shape. Of particular interest is an equation obtained by applying Gauss' divergence theorem twice. It is shown that this equation can be simply transformed to another expression which has been widely used for calculating Coulomb energies, with this derivation implying a third formula. The three formulas are also expressed in cylindrical coordinates for charge distributions possessing axial symmetry. For such shapes, numerical studies are presented showing the computational times and errors involved in calculating the Coulomb energies and generalized forces using Gaussian-Legendre quadrature formulas. It is shown that the double-divergence-derived formula is faster and more accurate than the other two surface-integral formulas and other formulas used in the literature

  9. Scaling and charge ratio in the energy range 1-10 TeV

    The purpose of the investigation was to study the spectra of generation of neutral and charged pions in the upper atmosphere in order to establish the scaling behaviour of the multiple birth of particles at primary particle energies above the acceleration energies. The study of the spectrum gamma-quanta in the atmosphere and the muon spectrum at the sea level made it possible to adjust the pion generation spectrum. In experiments with emulsion chambers the spectra of gamma-quanta and electrons at different zenith angles at two levels in the atmosphere (225 and 700 gxcm-2) and the muon spectrum at the sea level were determined. The obtained data on pion birth in the atmosphere pointed to the conservation of scale and charge invariance in pion birth at nucleon energies of 1012-1014 eV

  10. Surface charging of phosphors and its effects on cathodoluminescence at low electron energies

    Measurements of the threshold for secondary electron emission and shifts of the carbon Auger line position have been used to deduce the surface potential of several common phosphors during irradiation by electrons in the 0.5--5.0 keV range. All of the insulating phosphors display similar behavior: the surface potential is within ±1 V of zero at low electron energies. However, above 2--3 kV it becomes increasingly negative, reaching hundreds of volts within 1 keV of the turn-on energy. The electron energy at which this charging begins decreases dramatically after Coulomb aging at 17 microA/cm2 for 30--60 min. Measurements using coincident electron beams at low and high electron energies to control the surface potential were made to investigate the dependence of the cathodoluminescence (CL) process on charging. Initially, the CL from the two beams is identical to the sum of the separate beam responses, but after Coulomb aging large deviations from this additivity are observed. These results indicate that charging has important, detrimental effects on CL efficiency after prolonged e-beam irradiation. Measurements of the electron energy dependence of the CL efficiency before and after Coulomb aging will also be presented, and the implications of these data on the physics of the low-voltage CL process will be discussed

  11. Experimental investigation on charging and discharging performance of absorption thermal energy storage system

    Highlights: • A prototype of ATES using LiBr/H2O was designed and built. • Charging and discharging performances of ATES system were investigated. • ESE and ESD for cooling, domestic hot water and heating were obtained. - Abstract: Because of high thermal storage density and little heat loss, absorption thermal energy storage (ATES) is known as a potential thermal energy storage (TES) technology. To investigate the performance of the ATES system with LiBr–H2O, a prototype with 10 kW h cooling storage capacity was designed and built. The experiments demonstrated that charging and discharging processes are successful in producing 7 °C chilled water, 65 °C domestic hot water, or 43 °C heating water to meet the user’s requirements. Characteristics such as temperature, concentration and power variation of the ATES system during charging and discharging processes were investigated. The performance of the ATES system for supplying cooling, heating or domestic hot water was analyzed and compared. The results indicate that the energy storage efficiencies (ESE) for cooling, domestic hot water and heating are 0.51, 0.97, 1.03, respectively, and the energy storage densities (ESD) for cooling, domestic hot water and heating reach 42, 88, 110 kW h/m3, respectively. The performance is better than those of previous TES systems, which proves that the ATES system using LiBr–H2O may be a good option for thermal energy storage

  12. Energy-dependent Charge States and Their Connection with Ion Abundances in Impulsive Solar Energetic Particle Events

    DiFabio, R.; Guo, Z.; Möbius, E.; Klecker, B.; Kucharek, H.; Mason, G. M.; Popecki, M.

    2008-11-01

    Impulsive solar energetic particle (SEP) events show substantial enhancements of heavy ions and 3He over the composition in the Sun's atmosphere. Mass per charge dependent acceleration mechanisms have been proposed to account for this preferential acceleration. However, a problem emerged for all the preferential acceleration models with the measurement of ionization states near 1 MeV nucleon-1, which showed that ions from C to Mg are fully stripped, a challenge that had been recognized early on. Since all models relied on differences in the charge-to-mass ratio to enable preferential acceleration, the proposed mechanisms were incompatible with this observation. Recent observations of the ionic charge states at lower energies have revealed a dependence on energy, with the charge states decreasing for lower energy ions. This raises the possibility that the low-energy charge states reflect the plasma conditions at the acceleration site, while the high-energy charge states are due to stripping low in the solar corona. In a survey of impulsive events we show that the increase of the Fe charge states with energy is highly significant for the sample of events and thus most likely a general feature of impulsive events. To see whether there is a connection between the enhancements and charge states, we extended the ACE SEPICA charge-state observations to lower energies and combined them with the ion fluxes from ACE ULEIS for impulsive events observed between 1997 and 2000. We find a positive correlation between the abundance ratios and the charge states at low energy, while the charge states at the highest energy do not demonstrate such dependence. This supports the idea that the higher mass particles are preferentially accelerated before being stripped.

  13. Charge exchange and energy loss of slowed down heavy ions channeled in silicon crystals

    This work is devoted to the study of charge exchange processes and of the energy loss of highly charged heavy ions channeled in thin silicon crystals. The two first chapters present the techniques of heavy ion channeling in a crystal, the ion-electron processes and the principle of our simulations (charge exchange and trajectory of channeled ions). The next chapters describe the two experiments performed at the GSI facility in Darmstadt, the main results of which follow: the probability per target atom of the mechanical capture (MEC) of 20 MeV/u U91+ ions as a function of the impact parameter (with the help of our simulations), the observation of the strong polarization of the target electron gas by the study of the radiative capture and the slowing down of Pb81+ ions from 13 to 8,5 MeV/u in channeling conditions for which electron capture is strongly reduced. (author)

  14. Energy and centrality dependences of charged multiplicity pseudorapidity density in relativistic nuclear collisions

    Zhou Dai Mei; Sá Ben-Hao; Li Zhong Dao

    2002-01-01

    Using a hadron and string cascade model, JPCIAE, and the corresponding Monte Carlo events generator, the energy and centrality dependences of charged particle pseudorapidity density in relativistic nuclear collisions were studied. Within the framework of this model, both the relativistic p anti p experimental data and the PHOBOS and PHENIX Au + Au data could be reproduced fairly well without retuning the model parameters. The author shows that since is not a well defined physical variable both experimentally and theoretically, the charged particle pseudorapidity density per participant pair can increase and also can decrease with increasing of , so it may be hard to use charged particle pseudorapidity density per participant pair as a function of to distinguish various theoretical models for particle production

  15. Charged particle assisted nuclear reactions in solid state environment: renaissance of low energy nuclear physics

    Kálmán, Péter

    2015-01-01

    The features of electron assisted neutron exchange processes in crystalline solids are survayed. It is stated that, contrary to expectations, the cross section of these processes may reach an observable magnitude even in the very low energy case because of the extremely huge increment caused by the Coulomb factor of the electron assisted processes and by the effect of the crystal-lattice. The features of electron assisted heavy charged particle exchange processes, electron assisted nuclear capure processes and heavy charged particle assisted nuclear processes are also overviewed. Experimental observations, which may be related to our theoretical findings, are dealt with. The anomalous screening phenomenon is related to electron assisted neutron and proton exchange processes in crystalline solids. A possible explanation of observations by Fleischmann and Pons is presented. The possibility of the phenomenon of nuclear transmutation is qualitatively explained with the aid of usual and charged particle assisted r...

  16. Energy and centrality dependences of charged multiplicity pseudorapidity density in relativistic nuclear collisions

    Using a hadron and string cascade model, JPCIAE, and the corresponding Monte Carlo events generator, the energy and centrality dependences of charged particle pseudorapidity density in relativistic nuclear collisions were studied. Within the framework of this model, both the relativistic p anti p experimental data and the PHOBOS and PHENIX Au + Au data could be reproduced fairly well without retuning the model parameters. The author shows that since part> is not a well defined physical variable both experimentally and theoretically, the charged particle pseudorapidity density per participant pair can increase and also can decrease with increasing of part>, so it may be hard to use charged particle pseudorapidity density per participant pair as a function of part> to distinguish various theoretical models for particle production

  17. Unusual features of charge carrier traps energy spectra in silicon organic polymers revealed by advanced TSL

    Highlights: ► The improved technique of the fractional TSL registration has been elaborated. ► The discrete energies of the charge carrier traps were observed for the PDHS film. ► The TSL activation energies correlate with the Raman Ag modes of the silicon chain. ► The width of TSL curve is generally due to the frequency factor dispersion. - Abstract: The peculiarities of charge carrier traps’ energy spectra in poly (di-n-hexylsilane) films have been studied by the enhanced fractional thermally stimulated luminescence (TSL) in the temperature range of 5–200 K. For the first time, we have shown that the majority of fractional energy values (>80%) is distributed between a set of horizontal energy levels suggesting a discontinuity of the traps’ energy spectrum. These data distinctly differ from the results of earlier studies where a quasilinear dependence of the activation energy on temperature was found. It is shown that the significant width of TSL bands originates from the dispersion of the frequency factor. It is also established that the values obtained for the activation energy correlate well with the frequencies of the symmetric Raman active Ag modes at 268 and 373 cm−1 of the silicon chain, which confirms the suggestion about the hole location on the segments of the silicon organic polymers backbone.

  18. Towards hot electron mediated charge exchange in hyperthermal energy ion-surface interactions

    Ray, M. P.; Lake, R. E.; Thomsen, Lasse Bjørchmar;

    2010-01-01

    electrons useful for driving chemical reactions at surfaces. Using the binary collision approximation and a nonadiabatic model that takes into account the time-varying nature of the ion–surface interaction, the energy loss of the ions is reproduced. The energy loss for Na + ions incident on the devices...... shows that the primary energy loss mechanism is the atomic displacement of Au atoms in the thin film of the metal–oxide–semiconductor device. We propose that neutral particle detection of the scattered flux from a biased device could be a route to hot electron mediated charge exchange....

  19. The Low-Energy Charged Particle (LECP) experiment on the Voyager Spacecraft

    The Low Energy Charged Particle (LECP) experiment on the Voyager spacecraft is designed to provide comprehensive measurements of energetic particles in the Jovian, Saturnian, Uranian and interplanetary environments. These measurements will be used in establishing the morphology of the magnetospheres of Saturn and Uranus, including bow shock, magnetosheath, magnetotail, trapped radiation, and satellite-energetic particle interactions. The experiment consists of two subsystems, the Low Energy Magnetospheric Particle Analyzer (LEMPA) whose design is optimized for magnetospheric measurements, and the Low Energy Particle Telescope (LEPT) whose design is optimized for measurements in the distant magnetosphere and the interplanetary medium. (Auth.)

  20. Energy losses of fast heavy multiply charged structural ions in collisions with complex atoms

    Matveev, V. I.; Sidorov, D. B.

    2007-07-01

    A nonperturbatve theory of energy losses of fast heavy multiply charged structural ions in collisions with neutral complex atoms is elaborated with allowance for simultaneous excitations of ionic and atomic electron shells. Formulas for the effective deceleration that are similar to the well-known Bethe-Bloch formulas are derived. By way of example, the energy lost by partially stripped U q+ ions (10 ≤ q ≤ 70) colliding with argon atoms and also the energy lost by Au, Pb, and Bi ions colliding with various targets are calculated. The results of calculation are compared with experimental data.

  1. Excitation Functions for Charged Particle Induced Reactions in Light Elements at Low Projectile Energies

    The present chapter has been formulated with the aim of making it useful in various fields of nuclear applications with emphasis on charged particle activation analysis. Activation analysis of light elements using charged particles has proved to be an important tool in solving various problems in analytical chemistry, e g those associated with metal surfaces. Scientists desiring to evaluate the distribution of light elements in the surface of various matrices using charged particle reactions require accurate data on cross sections in the MeV-region. A knowledge of cross section data and yield-functions is of great interest in many applied fields involving work with charged particles, such as radiological protection and health physics, material research, semiconductor material investigations and corrosion chemistry. The authors therefore decided to collect a limited number of data which find use in these fields. Although the compilation is far from being complete, it is expected to be of assistance in devising measurements of charged particle reactions in Van de Graaff or other low energy accelerators

  2. Design of the low energy beam transport line between CARIBU and the EBIS charge breeder

    An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed to breed radioactive beams from the CAlifornium Rare Isotope Breeder Upgrade (CARIBU) facility at ATLAS. The EBIS-CB will replace the existing ECR charge breeder to increase the intensity and improve the purity of reaccelerated radioactive ion beams. The EBIS-CB is in the final stage of off-line commissioning. Currently, we are developing a low energy beam transport (LEBT) system to transfer CARIBU beams to the EBIS-CB. As was originally planned, an RFQ cooler-buncher will precede the EBIS-CB. Recently, it was decided to include a multi-reflection time-of-flight (MR-TOF) mass-spectrometer following the RFQ. MR-TOF is a relatively new technology used to purify beams with a mass-resolving power up to 3×105 as was demonstrated in experiments at CERN/ISOLDE. Very high purity singly-charged radioactive ion beams will be injected into the EBIS for charge breeding and due to its inherent properties, the EBIS-CB will maintain the purity of the charge bred beams. Possible contamination of residual gas ions will be greatly suppressed by achieving ultra-high vacuum in the EBIS trap. This paper will present and discuss the design of the LEBT and the overall integration of the EBIS-CB into ATLAS

  3. Charging studies of heat packs using parabolic dish solar energy concentrator for extreme conditions

    Kumar, Rohitash; Vyas, Sumita; Kumar, Ravindra; Dixit, Ambesh

    2016-05-01

    Parabolic dish solar energy concentrator with aperture diameter 1.4 m and focal length 0.32 m is designed and fabricated to charge and store solar thermal energy in phase change material (PCM) based heat packs. Overall heat loss factor, heat duty, over all thermal efficiency, and optical efficiency factor are calculated using water sensible heating and cooling tests and values are 16.11 W m-2 K-1, 546.9 W, 49.2% and 0.62 respectively. The performance characteristic curve is generated using these parameters to understand its performance at different ambient temperatures and solar insolation. The fabricated concentrator has been used to charge 16 PCM heat packs with 150 g PCM in each heat pack, which took about 35 minutes for complete charging of PCM heat packs at average ambient temperature 39 °C and solar radiation flux density 715 W m-2 K-1. The charged heat packs are subjected to discharge studies at average ambient temperature about - 7 °C and observed heat release in the temperature range of 48 to 40 °C for 50 minutes, suggesting its applications for comfort and therapeutic applications in high altitude areas.

  4. Organic photovoltaic devices with concurrent solar energy harvesting and charge storage capability

    Takshi, Arash; Tevi, Tete; Rahimi, Fatemeh

    2015-09-01

    Due to large variation of the solar energy availability in a day, energy storage is required in many applications when solar cells are used. However, application of external energy storage devices, such as batteries and supercapacitors, increases the cost of solar energy systems and requires additional charging circuitry. This combination is bulky and relatively expensive, which is not ideal for many applications. In this work, a novel idea is presented for making electrochemical devices with dual properties of solar energy harvesting and internal charge storage. The device is essentially a supercapacitor with a photoactive electrode. Energy harvesting occurs through light absorption at one of the electrodes made of a composite of a conducting polymer (i.e. PEDOT:PSS) and a Porphyrin dye. The energy storage takes place in the both photoactive and counter electrode (CE). We have studied the effect of the CE material on the device characteristics. Using Y-Carbon (a commercial available electrode), an open circuit voltage of 0.49 V was achieved in light across the cell with ~1 mF capacitance. The other two choices for CE were activated carbon and carbon nanotube based electrodes. The cyclic voltammetry and impedance spectroscopy demonstrated that the Y Carbon electrode was a better match.

  5. Energy loss and charge state distribution of calcium ions in dense moderately coupled carbon plasma

    In this thesis the interaction of swift calcium ions (Energy: 3.5 MeV/u) with a dense and moderately coupled carbon plasma (Coupling parameter: Γ=0.1-0.5) is investigated. The plasma state is generated by heating a thin carbon foil volumetrically by thermal X-ray radiation. The thermal X-ray radiation itself is generated by the conversion of a high energy laser beam in a hohlraum cavity. Compared to earlier ion stopping experiments the electron density and the plasma coupling parameter could be increased by an order of magnitude. This work provides the first time experimental energy loss and charge state distribution data in this moderately coupled interaction regime. The thesis consists of a theoretical part where the ion beam plasma interaction is studied for a broad range of plasma parameters and an experimental part where the ion beam interaction with the hohlraum plasma target is measured. All the described experiments were carried out at the GSI Helmholtzzentrum fuer Schwerionenforschung in Darmstadt. This facility offers the unique possibility to combine a heavy ion beam from an accelerator with a high energy laser beam in one interaction chamber. An intense laser pulse (150 J of laser energy in 1 ns at λL=527 nm) is focused inside a 600 μm diameter spherical cavity and generates a hot gold plasma that emits X-rays. The absorbed and reemitted radiation establishes a spatially uniform temperature distribution in the cavity and serves as an intense, isotropic X-ray source with a quasi-thermal spectral distribution. These thermal X-rays with a radiation temperature of Tr=98±6 eV then propagate into a secondary cylindrical hohlraum (diameter: 1000 μm, length: 950 μm) where they volumetrically heat two thin carbon foils to the plasma state. The radiation temperature in the secondary hohlraum is Tr=33±5 eV. This indirect laser heating scheme has the advantage that the whole sample volume is instantaneously heated and that the plasma is inertially and

  6. Temporal evolution of ion energy distribution functions and ion charge states of Cr and Cr-Al pulsed arc plasmas

    To study the temporal evolution of ion energy distribution functions, charge-state-resolved ion energy distribution functions of pulsed arc plasmas from Cr and Cr-Al cathodes were recorded with high time resolution by using direct data acquisition from a combined energy and mass analyzer. The authors find increases in intensities of singly charged ions, which is evidence that charge exchange reactions took place in both Cr and Cr-Al systems. In Cr-Al plasmas, the distributions of high-charge-state ions exhibit high energy tails 50 μs after discharge ignition, but no such tails were observed at 500 μs. The energy ratios of ions of different charge states at the beginning of the pulse, when less neutral atoms were in the space in front of the cathode, suggest that ions are accelerated by an electric field. The situation is not so clear after 50 μs due to particle collisions. The initial mean ion charge state of Cr was about the same in Cr and in Cr-Al plasmas, but it decreased more rapidly in Cr-Al plasmas compared to the decay in Cr plasma. The faster decay of the mean ion charge state and ion energy caused by the addition of Al into a pure Cr cathode suggests that the mean ion charge state is determined not only by ionization processes at the cathode spot but also by inelastic collision between different elements

  7. Temporal evolution of ion energy distribution functions and ion charge states of Cr and Cr-Al pulsed arc plasmas

    Tanaka, Koichi, E-mail: tanak@mmc.co.jp [Central Research Institute, Mitsubishi Materials Corporation, 1002-14 Mukohyama, Naka-shi, Ibaraki 311-0102 (Japan); Anders, André [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 53, Berkeley, California 94720 (United States)

    2015-11-15

    To study the temporal evolution of ion energy distribution functions, charge-state-resolved ion energy distribution functions of pulsed arc plasmas from Cr and Cr-Al cathodes were recorded with high time resolution by using direct data acquisition from a combined energy and mass analyzer. The authors find increases in intensities of singly charged ions, which is evidence that charge exchange reactions took place in both Cr and Cr-Al systems. In Cr-Al plasmas, the distributions of high-charge-state ions exhibit high energy tails 50 μs after discharge ignition, but no such tails were observed at 500 μs. The energy ratios of ions of different charge states at the beginning of the pulse, when less neutral atoms were in the space in front of the cathode, suggest that ions are accelerated by an electric field. The situation is not so clear after 50 μs due to particle collisions. The initial mean ion charge state of Cr was about the same in Cr and in Cr-Al plasmas, but it decreased more rapidly in Cr-Al plasmas compared to the decay in Cr plasma. The faster decay of the mean ion charge state and ion energy caused by the addition of Al into a pure Cr cathode suggests that the mean ion charge state is determined not only by ionization processes at the cathode spot but also by inelastic collision between different elements.

  8. High-energy charged particle bursts in the near-Earth space as earthquake precursors

    S. Yu. Aleksandrin

    Full Text Available The experimental data on high-energy charged particle fluxes, obtained in various near-Earth space experiments (MIR orbital station, METEOR-3, GAMMA and SAMPEX satellites were processed and analyzed with the goal to search for particle bursts. Particle bursts have been selected in every experiment considered. It was shown that the significant part of high-energy charged particle bursts correlates with seismic activity. Moreover, the particle bursts are observed several hours before strong earthquakes; L-shells of particle bursts and corresponding earthquakes are practically the same. Some features of a seismo-magnetosphere connection model, based on the interaction of electromagnetic emission of seismic origin and radiation belt particles, were considered.

    Key words. Ionospheric physics (energetic particles, trapped; energetic particles, precipitating; magnetosphere-ionosphere interactions

  9. Low-energy pion double charge exchange and nucleon-nucleon correlations in nuclei

    Recent measurements of pion double-charge exchange (DCX) at energies 20 to 70 MeV are providing a new means for studying nucleon-nucleon correlations in nuclei. At these energies the nucleus is relatively transparent, allowing simpler theoretical models to be used in interpreting the data and leading to a clearer picture. Also the contribution to DCX of sequential charge-exchange scattering through the intermediate analog state is suppressed near 50 MeV and transitions through non-analog intermediate states become very important. Recent theoretical studies by several groups have shown that while transitions through the analog route involve relatively long nucleon-nucleon distances, those through non-analog intermediate states obtain nearly half their strength from nucleon pairs with less than 1 fermi separation. Thus DCX near 50 MeV is an excellent way to study short-range nucleon-nucleon correlations. 31 refs., 29 figs., 4 tabs

  10. Modeling Charge-Sign Asymmetric Solvation Free Energies With Nonlinear Boundary Conditions

    Bardhan, Jaydeep P

    2014-01-01

    We show that charge-sign-dependent asymmetric hydration can be modeled accurately using linear Poisson theory but replacing the standard electric-displacement boundary condition with a simple nonlinear boundary condition. Using a single multiplicative scaling factor to determine atomic radii from molecular dynamics Lennard-Jones parameters, the new model accurately reproduces MD free-energy calculations of hydration asymmetries for (i) monatomic ions, (ii) titratable amino acids in both their protonated and unprotonated states, and (iii) the Mobley "bracelet" and "rod" test problems [J. Phys. Chem. B, v. 112:2408, 2008]. Remarkably, the model also justifies the use of linear response expressions for charging free energies. Our boundary-element method implementation demonstrates the ease with which other continuum-electrostatic solvers can be extended to include asymmetry.

  11. Energy dependence of the charged multiplicity in deep inelastic scattering at HERA

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2008-03-15

    The charged multiplicity distributions and the mean charged multiplicity have been investigated in inclusive neutral current deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 38.6 pb{sup -1}. The measurements were performed in the current region of the Breit frame, as well as in the current fragmentation region of the hadronic centre-of-mass frame. The KNO-scaling properties of the data were investigated and the energy dependence was studied using different energy scales. The data are compared to results obtained in e{sup +}e{sup -} collisions and to previous DIS measurements as well as to leading-logarithm parton-shower Monte Carlo predictions. (orig.)

  12. Energy loss of charged particles at large distances from metal surfaces

    We present a theoretical study of the dissipative component of the force acting on a highly charged ion moving in front of a solid surface at large distances. The friction force (stopping power) of the surface is analyzed employing both the specular-reflection model and time-dependent density functional theory (TDDFT). Contributions from particle-hole and plasmon excitations are discussed. A simple method to include the correction due to the finite width of the plasmon resonance at large wavelength into the TDDFT description of the stopping power is suggested. We present applications to the energy loss of charged particles undergoing distant collisions at grazing incidence angles with the internal surface of the microcapillary. Our results indicate that the correlation between the angular distribution and the energy loss of transmitted ions can be used to probe the dielectric properties of the capillary material at large distances

  13. Universal behavior of charged particle production in heavy ion collisions at RHIC energies

    The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at √SNN = 19.6, 130 and 200 GeV. Two kinds of universal behavior are observed in charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/p-barp and e+e- data. ch>/part/2> in nuclear collisions at high energy scales with √s in a similar way as Nch in e+e- collisions and has a very weak centrality dependence. This feature may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions

  14. Computer simulation of coherent interaction of charged particles and photons with crystalline solids at high energies

    Apyan, A

    2007-01-01

    Monte Carlo simulation code has been developed and tested for studying the passage of charged particle beams and radiation through the crystalline matter at the energies from tens of MeV up to hundreds of GeV. The developed Monte Carlo code simulates electron, positron and photon shower in single crystals and amorphous media. The Monte Carlo code tracks the all generations of charged particles and photons through the aligned crystal by taking into account the parameters of incoming beam, multiple scattering, energy loss, emission angles, transverse dimension of beams, and linear polarization of produced photons. The simulation results are compared with the CERN-NA-59 experimental data. The realistic descriptions of the electron and photon beams and the physical processes within the silicon and germanium single crystals have been implemented.

  15. Charge transfer in the interactions of partially stripped ions with atoms at intermediate and high energies

    The Coulomb-Born (CB) approximation has been employed to study charge transfer cross sections in collisions of Cq+, Nq+ and Oq+ (q = 1-5) with atomic hydrogen in ground state in the energy range of 30-200 keV/amu. The interaction of the active electron with the incoming projectile ion has been approximated by a model potential containing both a long-range part and a short-range part. Variations of total capture cross sections with impact energy compare favourable well with the available experimental observations and with other theoretical findings. In addition, sub-shell distributions of total capture cross sections are given in graphical form. However, we are unable to find any oscillation in the charge-state dependence of total capture cross sections. (author)

  16. A 2-D Implicit, Energy and Charge Conserving Particle In Cell Method

    McPherson, Allen L. [Los Alamos National Laboratory; Knoll, Dana A. [Los Alamos National Laboratory; Cieren, Emmanuel B. [Los Alamos National Laboratory; Feltman, Nicolas [Los Alamos National Laboratory; Leibs, Christopher A. [Los Alamos National Laboratory; McCarthy, Colleen [Los Alamos National Laboratory; Murthy, Karthik S. [Los Alamos National Laboratory; Wang, Yijie [Los Alamos National Laboratory

    2012-09-10

    Recently, a fully implicit electrostatic 1D charge- and energy-conserving particle-in-cell algorithm was proposed and implemented by Chen et al ([2],[3]). Central to the algorithm is an advanced particle pusher. Particles are moved using an energy conserving scheme and are forced to stop at cell faces to conserve charge. Moreover, a time estimator is used to control errors in momentum. Here we implement and extend this advanced particle pusher to include 2D and electromagnetic fields. Derivations of all modifications made are presented in full. Special consideration is taken to ensure easy coupling into the implicit moment based method proposed by Taitano et al [19]. Focus is then given to optimizing the presented particle pusher on emerging architectures. Two multicore implementations, and one GPU (Graphics Processing Unit) implementation are discussed and analyzed.

  17. Study of a charge-coupled device for high-energy-particle detection

    This presentation is based on measurements made to evaluate the application of charge-coupled devices as detectors of high-energy particles. The experiment was performed with a Fairchild Linear 256-Cell CCD111 array (size 8μm x 17 μm/cell), utilizing a light source instead of a particle beam. It was observed that the minimum detectable signal was limited to approx. 488 electrons at -500C, where the readout and exposure times were about 260 ms and 400 ms respectively. The transfer inefficiency of the CCD111 was determined to be approx. 10-4. It has been concluded that at a lower temperature (approx. -1000C) or with faster readout (approx. 10 ms), the CCD111 would be able to detect the total deposited energy of minimum-ionizing charged particles

  18. UNIVERSAL BEHAVIOR OF CHARGED PARTICLE PRODUCTION IN HEAVY ION COLLISIONS AT RHIC ENERGIES

    The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at √(sNN) = 19.6, 130 and 200 GeV. Two observations indicate universal behavior of charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/(bar p)p and e+e- data. ch>/part/2> in nuclear collisions at high energy scales with √s in a similar way as Nch in e+e- collisions and has a very weak centrality dependence. These features may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions

  19. Low-energy pion double charge exchange and nucleon-nucleon correlations in nuclei

    Leitch, M.J.

    1989-01-01

    Recent measurements of pion double-charge exchange (DCX) at energies 20 to 70 MeV are providing a new means for studying nucleon-nucleon correlations in nuclei. At these energies the nucleus is relatively transparent, allowing simpler theoretical models to be used in interpreting the data and leading to a clearer picture. Also the contribution to DCX of sequential charge-exchange scattering through the intermediate analog state is suppressed near 50 MeV and transitions through non-analog intermediate states become very important. Recent theoretical studies by several groups have shown that while transitions through the analog route involve relatively long nucleon-nucleon distances, those through non-analog intermediate states obtain nearly half their strength from nucleon pairs with less than 1 fermi separation. Thus DCX near 50 MeV is an excellent way to study short-range nucleon-nucleon correlations. 31 refs., 29 figs., 4 tabs.

  20. Numerical Studies of Electromagnetic Instabilities in Intense Charged Particle Beams with Large Energy Anisotropy

    Startsev, Edward; Lee, Wei-li

    2005-01-01

    In intense charged particle beams with large energy anisotropy, free energy is available to drive transverse electromagnetic Weibel-type instabilities. Such slow-wave transverse electromagnetic instabilities can be described by the so-called Darwin model, which neglects the fast-wave portion of the displacement current. The Weibel instability may also lead to an increase in the longitudinal velocity spread, which would make the focusing of the beam difficult and impose a limit on the minimum spot size achievable in heavy ion fusion experiments. This paper reports the results of recent numerical studies of the Weibel instability using the Beam Eigenmode And Spectra (bEASt) code for space-charge-dominated, low-emittance beams with large tune depression. To study the nonlinear stage of the instability, the Darwin model is being developed and incorporated into the Beam Equilibrium Stability and Transport(BEST) code.

  1. Universal behavior of charged particle production in heavy ion collisions at RHIC energies

    Steinberg, Peter A.; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Ballintijn, M.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Holyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.; Phobos Collaboration

    2003-04-01

    The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at √ SNN = 19.6, 130 and 200 GeV. Two kinds of universal behavior are observed in charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/ overlinepp and e +e - data. / in nuclear collisions at high energy scales with √ s in a similar way as Nch in e +e - collisions and has a very weak centrality dependence. This feature may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions.

  2. Space distribution and energy straggling of charged particles via Fokker-Planck equation

    The Fokker-Planck equation describing a beam of charged particles entering a homogeneous medium is solved here for a stationary case. Interactions are taken into account through Coulomb cross-section. Starting from the charged-particle distribution as a function of velocity and penetration depth, some important kinetic quantities are calculated, like mean velocity, range and the loss of energy per unit space. In such quantities the energy straggling is taken into account. This phenomenon is not considered in the continuous slowing-down approximation that is commonly used to obtain the range and the stopping power. Finally the well-know Bohr of Bethe formula is found as a first-order approximation of the Fokker-Planck equation

  3. Development of low energy ion beam system for space charge compensation experiments

    A low energy ion beam system for space charge compensation (SCC) experiments was developed and evaluated. This system was designed for observation of SCC of a positive ion beam with an electron beam. The system consisted of the ion source chamber and the SCC experiment chamber. The ion source chamber was equipped with the compact microwave ion source for low voltage extraction. Ion current at initial position of the analysis chamber was 84 μA at extraction voltage of 500 V, and satisfied a condition to observe the SCC effect clearly. In order to evaluate the SCC, we measured the arrival ion current by supplying thermionic electrons, which were extracted from a tungsten filament driven by ac voltage. As the electron supply, the arrival ion current increased from 40 to 68 μA at the potential of filament of +3 eV which produced the thermionic electron with extremely low energy extracted by space charge of the ion beam

  4. Charge and energy transfer interplay in hybrid sensitized solar cells mediated by graphene quantum dots

    Highlights: • We report a one pot synthesis metod of GQD with controlled size and optoelectronic properties. • An improvement of common N3-DSSC characteristics is achieved when GQDs are used as co-sensitiser. • The role of GQD as cosensitisers in hybrid DSSC was investigated and the interplay between charge and energy transfer phenomena mediated by GQDs was demonstrated. • The GQDs presence determines an inhibition of the recombination processes at the TiO2/electrolyte interface. - Abstract: We explored the role of graphene quantum dots (GQDs) as co-sensitizers in hybrid dye sensitized solar cell (DSSC) architectures, focusing on various concurring mechanisms, such as: charge transfer, energy transfer and recombination rate, towards light harvesting improvement. GQDs were prepared by the hydrothermal method that allows the tuning of electronic levels and optical properties by employing appropriate precursors and synthesis conditions. The aim was to realize a type II alignment for TiO2/GQD/dye hybrid configuration, using standard N3 Ru-dye in order to improve charge transfer. When GQDs were used as co-sensitizers together with N3 Ru-dye, an improvement in power conversion efficiency was achieved, as shown by electrical measurements. The experimental analysis indicates that this improvement arises from the interplay of various mechanisms mediated by GQDs: (i) enhancement of charge separation and collection due to the cascaded alignment of the energy levels; (ii) energy transfer from GQDs to N3 Ru-dye due to the overlap between GQD photoluminescence and N3 Ru-dye absorption spectra; and (iii) reduction of the electron recombination to the redox couple due to the inhibition of the back electron transfer to the electrolyte by the GQDs

  5. Novel charge pump converter with Tunnel FET devices for ultra-low power energy harvesting sources

    Nunes Cavalheiro, David Manuel; Moll Echeto, Francisco de Borja; Valtchev, Stanimir

    2015-01-01

    Compared to conventional technologies, the superior electrical characteristics of III-V Tunnel FET (TFET) devices can highly improve the process of energy harvesting conversion at ultra-low input voltage operation (sub-0.25V). In order to extend the input voltage/power range of operation in conventional charge pump topologies with TFET devices, it is of the major importance to reduce the band-to-band tunneling current when the transistor is under reverse bias conditions. This paper p...

  6. Characterization and Modeling of Received Signal Strength and Charging Time for Wireless Energy Transfer

    Uthman Baroudi; Amin-ud-din Qureshi; Samir Mekid

    2015-01-01

    Wireless sensor networks can provide effective means for monitoring and controlling a wide range of applications. Recently, tremendous effort was directed towards devising sensors powered from ambient sources such as heat, wind, and vibration. Wireless energy transfer is another source that has attractive features that make it a promising candidate for supplying power to wireless sensor nodes. This paper is concerned with characterizing and modeling the charging time and received signal stren...

  7. Transport and effects of high-energy charged fusion-products in tokamaks

    An explicit expression that describes the guiding-center motion of a high-energy charged particle in a lossless, axisymmetric, low-beta (β less than or equal to 0.1) tokamak has been derived. The expression is valid in any type of toroidal and poloidal field configurations as long as the poloidal flux surfaces, specified by psi (r), are circular. A similar explicit expression is obtained for fields having a vertical stabilizing component, B/sub v/

  8. Plug-in vs. wireless charging: Life cycle energy and greenhouse gas emissions for an electric bus system

    Graphical abstract: In this study, plug-in and wireless charging for an all-electric bus system are compared from the life cycle energy and greenhouse gas (GHG) emissions perspectives. The comparison of life cycle GHG emissions is shown in the graph below. The major differences between the two systems, including the charger, battery and use-phase electricity consumption, are modeled separately and compared aggregately. In the base case, the wireless charging system consumes 0.3% less energy and emits 0.5% less greenhouse gases than plug-in charging system in the total life cycle. To further improve the energy and environmental performance of the wireless charging system, key parameters including grid carbon intensity and wireless charging efficiency are analyzed and discussed in this paper. - Highlights: • Compared life cycle energy and GHG emissions of wireless to plug-in charging. • Modeled a transit bus system to compare both charging methods as a case study. • Contrasted tradeoffs of infrastructure burdens with lightweighting benefits. • The wireless battery can be downsized to 27–44% of a plug-in charged battery. • Explored sensitivity of wireless charging efficiency & grid carbon intensity. - Abstract: Wireless charging, as opposed to plug-in charging, is an alternative charging method for electric vehicles (EVs) with rechargeable batteries and can be applicable to EVs with fixed routes, such as transit buses. This study adds to the current research of EV wireless charging by utilizing the Life Cycle Assessment (LCA) to provide a comprehensive framework for comparing the life cycle energy demand and greenhouse gas emissions associated with a stationary wireless charging all-electric bus system to a plug-in charging all-electric bus system. Life cycle inventory analysis of both plug-in and wireless charging hardware was conducted, and battery downsizing, vehicle lightweighting and use-phase energy consumption were modeled. A bus system in Ann Arbor

  9. Interconversion of functional motions between mesophilic and thermophilic adenylate kinases.

    Michael D Daily

    2011-07-01

    Full Text Available Dynamic properties are functionally important in many proteins, including the enzyme adenylate kinase (AK, for which the open/closed transition limits the rate of catalytic turnover. Here, we compare our previously published coarse-grained (double-well Gō simulation of mesophilic AK from E. coli (AKmeso to simulations of thermophilic AK from Aquifex aeolicus (AKthermo. In AKthermo, as with AKmeso, the LID domain prefers to close before the NMP domain in the presence of ligand, but LID rigid-body flexibility in the open (O ensemble decreases significantly. Backbone foldedness in O and/or transition state (TS ensembles increases significantly relative to AKmeso in some interdomain backbone hinges and within LID. In contact space, the TS of AKthermo has fewer contacts at the CORE-LID interface but a stronger contact network surrounding the CORE-NMP interface than the TS of AKmeso. A "heated" simulation of AKthermo at 375K slightly increases LID rigid-body flexibility in accordance with the "corresponding states" hypothesis. Furthermore, while computational mutation of 7 prolines in AKthermo to their AKmeso counterparts produces similar small perturbations, mutation of these sites, especially positions 8 and 155, to glycine is required to achieve LID rigid-body flexibility and hinge flexibilities comparable to AKmeso. Mutating the 7 sites to proline in AKmeso reduces some hinges' flexibilities, especially hinge 2, but does not reduce LID rigid-body flexibility, suggesting that these two types of motion are decoupled in AKmeso. In conclusion, our results suggest that hinge flexibility and global functional motions alike are correlated with but not exclusively determined by the hinge residues. This mutational framework can inform the rational design of functionally important flexibility and allostery in other proteins toward engineering novel biochemical pathways.

  10. Adenylate cyclase regulates elongation of mammalian primary cilia

    Ou, Young; Ruan, Yibing; Cheng, Min; Moser, Joanna J. [Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1 (Canada); Rattner, Jerome B. [Department of Cell Biology and Anatomy, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1 (Canada); Hoorn, Frans A. van der, E-mail: fvdhoorn@ucalgary.ca [Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1 (Canada)

    2009-10-01

    The primary cilium is a non-motile microtubule-based structure that shares many similarities with the structures of flagella and motile cilia. It is well known that the length of flagella is under stringent control, but it is not known whether this is true for primary cilia. In this study, we found that the length of primary cilia in fibroblast-like synoviocytes, either in log phase culture or in quiescent state, was confined within a range. However, when lithium was added to the culture to a final concentration of 100 mM, primary cilia of synoviocytes grew beyond this range, elongating to a length that was on average approximately 3 times the length of untreated cilia. Lithium is a drug approved for treating bipolar disorder. We dissected the molecular targets of this drug, and observed that inhibition of adenylate cyclase III (ACIII) by specific inhibitors mimicked the effects of lithium on primary cilium elongation. Inhibition of GSK-3{beta} by four different inhibitors did not induce primary cilia elongation. ACIII was found in primary cilia of a variety of cell types, and lithium treatment of these cell types led to their cilium elongation. Further, we demonstrate that different cell types displayed distinct sensitivities to the lithium treatment. However, in all cases examined primary cilia elongated as a result of lithium treatment. In particular, two neuronal cell types, rat PC-12 adrenal medulla cells and human astrocytes, developed long primary cilia when lithium was used at or close to the therapeutic relevant concentration (1-2 mM). These results suggest that the length of primary cilia is controlled, at least in part, by the ACIII-cAMP signaling pathway.

  11. Adenylate cyclase regulates elongation of mammalian primary cilia

    The primary cilium is a non-motile microtubule-based structure that shares many similarities with the structures of flagella and motile cilia. It is well known that the length of flagella is under stringent control, but it is not known whether this is true for primary cilia. In this study, we found that the length of primary cilia in fibroblast-like synoviocytes, either in log phase culture or in quiescent state, was confined within a range. However, when lithium was added to the culture to a final concentration of 100 mM, primary cilia of synoviocytes grew beyond this range, elongating to a length that was on average approximately 3 times the length of untreated cilia. Lithium is a drug approved for treating bipolar disorder. We dissected the molecular targets of this drug, and observed that inhibition of adenylate cyclase III (ACIII) by specific inhibitors mimicked the effects of lithium on primary cilium elongation. Inhibition of GSK-3β by four different inhibitors did not induce primary cilia elongation. ACIII was found in primary cilia of a variety of cell types, and lithium treatment of these cell types led to their cilium elongation. Further, we demonstrate that different cell types displayed distinct sensitivities to the lithium treatment. However, in all cases examined primary cilia elongated as a result of lithium treatment. In particular, two neuronal cell types, rat PC-12 adrenal medulla cells and human astrocytes, developed long primary cilia when lithium was used at or close to the therapeutic relevant concentration (1-2 mM). These results suggest that the length of primary cilia is controlled, at least in part, by the ACIII-cAMP signaling pathway.

  12. Calculations on charge state and energy loss of argon ions in partially and fully ionized carbon plasmas.

    Barriga-Carrasco, Manuel D; Casas, David; Morales, Roberto

    2016-03-01

    The energy loss of argon ions in a target depends on their velocity and charge density. At the energies studied in this work, it depends mostly on the free and bound electrons in the target. Here the random-phase approximation is used for analyzing free electrons at any degeneracy. For the plasma-bound electrons, an interpolation between approximations for low and high energies is applied. The Brandt-Kitagawa (BK) model is employed to depict the projectile charge space distribution, and the stripping criterion of Kreussler et al. is used to determine its equilibrium charge state Q(eq). This latter criterion implies that the equilibrium charge state depends slightly on the electron density and temperature of the plasma. On the other hand, the effective charge Q(eff) is obtained as the ratio between the energy loss of the argon ion and that of the proton for the same plasma conditions. This effective charge Q(eff) is larger than the equilibrium charge state Q(eq) due to the incorporation of the BK charge distribution. Though our charge-state estimations are not exactly the same as the experimental values, our energy loss agrees quite well with the experiments. It is noticed that the energy loss in plasmas is higher than that in the same cold target of about, ∼42-62.5% and increases with carbon plasma ionization. This confirms the well-known enhanced plasma stopping. It is also observed that only a small part of this energy loss enhancement is due to an increase of the argon charge state, namely only ∼2.2 and 5.1%, for the partially and the fully ionized plasma, respectively. The other contribution is connected with a better energy transfer to the free electrons at plasma state than to the bound electrons at solid state of about, ∼38.8-57.4%, where higher values correspond to a fully ionized carbon plasma. PMID:27078472

  13. Calculations on charge state and energy loss of argon ions in partially and fully ionized carbon plasmas

    Barriga-Carrasco, Manuel D.; Casas, David; Morales, Roberto

    2016-03-01

    The energy loss of argon ions in a target depends on their velocity and charge density. At the energies studied in this work, it depends mostly on the free and bound electrons in the target. Here the random-phase approximation is used for analyzing free electrons at any degeneracy. For the plasma-bound electrons, an interpolation between approximations for low and high energies is applied. The Brandt-Kitagawa (BK) model is employed to depict the projectile charge space distribution, and the stripping criterion of Kreussler et al. is used to determine its equilibrium charge state Qeq. This latter criterion implies that the equilibrium charge state depends slightly on the electron density and temperature of the plasma. On the other hand, the effective charge Qeff is obtained as the ratio between the energy loss of the argon ion and that of the proton for the same plasma conditions. This effective charge Qeff is larger than the equilibrium charge state Qeq due to the incorporation of the BK charge distribution. Though our charge-state estimations are not exactly the same as the experimental values, our energy loss agrees quite well with the experiments. It is noticed that the energy loss in plasmas is higher than that in the same cold target of about, ˜42 -62.5 % and increases with carbon plasma ionization. This confirms the well-known enhanced plasma stopping. It is also observed that only a small part of this energy loss enhancement is due to an increase of the argon charge state, namely only ˜2.2 and 5.1 % , for the partially and the fully ionized plasma, respectively. The other contribution is connected with a better energy transfer to the free electrons at plasma state than to the bound electrons at solid state of about, ˜38.8 -57.4 % , where higher values correspond to a fully ionized carbon plasma.

  14. Reaction mechanism and nuclear correlations study by low energy pion double charge exchange

    In pion double-charge-exchange (DCX) reactions, a positive (negative) pion is incident on a nucleus and a negative (positive) pion emerges. These reactions are of fundamental interest since the process must involve at least two nucleons in order to conserve charge. Although two nucleon processes are present in many reactions they are usually masked by the dominant single nucleon processes. DCX is unique in that respect since it is a two nucleon process in lowest order and thus may be sensitive to two-nucleon correlations. Measurements of low energy pion double-charge-exchange reactions to the double-isobaric-analog-state (DIAS) and ground-state (GS) of the residual nucleus provide new means for studying nucleon-nucleon correlations in nuclei. At low energies (Tπ 7/2 shell at energies ranging from 25 to 65 MeV. Cross sections were measured on 42,44,48Ca, 46,50Ti and 54Fe. The calcium isotopes make a good set of nuclei on which to study the effects of correlations in DCX reactions

  15. Design study of low-energy beam transport for multi-charge beams at RAON

    Bahng, Jungbae; Qiang, Ji; Kim, Eun-San

    2015-12-01

    The Rare isotope Accelerator Of Newness (RAON) at the Rare Isotope Science Project (RISP) is being designed to simultaneously accelerate beams with multiple charge states. It includes a driver superconducting (SC) linac for producing 200 MeV/u and 400 kW continuous wave (CW) heavy ion beams from protons to uranium. The RAON consists of a few electron cyclotron resonance ion sources, a low-energy beam transport (LEBT) system, a CW 81.25 MHz, 500 keV/u radio frequency quadrupole (RFQ) accelerator, a medium-energy beam transport system, the SC linac, and a charge-stripper system. The LEBT system for the RISP accelerator facility consists of a high-voltage platform, two 90° dipoles, a multi-harmonic buncher (MHB), solenoids, electrostatic quadrupoles, a velocity equalizer, and a diagnostic system. The ECR ion sources are located on a high-voltage platform to reach an initial beam energy of 10 keV/u. After extraction, the ion beam is transported through the LEBT system to the RFQ accelerator. The generated charge states are selected by an achromatic bending system and then bunched by the MHB in the LEBT system. The MHB is used to achieve a small longitudinal emittance in the RFQ by generating a sawtooth wave with three harmonics. In this paper, we present the results and issues of the beam dynamics of the LEBT system.

  16. Potential energy, force distribution and oscillatory motion of chloride ion inside electrically charged carbon nanotubes

    Sadeghi, F.; Ansari, R.; Darvizeh, M.

    2016-06-01

    In this research, a continuum-based model is presented to explore potential energy, force distribution and oscillatory motion of ions, and in particular chloride ion, inside carbon nanotubes (CNTs) decorated by functional groups at two ends. To perform this, van der Waals (vdW) interactions between ion and nanotube are modeled by the 6-12 Lennard-Jones (LJ) potential, whereas the electrostatic interactions between ion and functional groups are modeled by the Coulomb potential and the total interactions are analytically derived by summing the vdW and electrostatic interactions. Making the assumption that carbon atoms and charge of functional groups are all uniformly distributed over the nanotube surface and the two ends of nanotube, respectively, a continuum approach is utilized to evaluate the related interactions. Based on the actual force distribution, the equation of motion is also solved numerically to arrive at the time history of displacement and velocity of inner core. With respect to the proposed formulations, comprehensive studies on the variations of potential energy and force distribution are carried out by varying functional group charge and nanotube length. Moreover, the effects of these parameters together with initial conditions on the oscillatory behavior of system are studied and discussed in detail. It is found out that chloride ion escapes more easily from negatively charged CNTs which is followed by uncharged and positively charged ones. It is further shown that the presence of functional groups leads to enhancing the operating frequency of such oscillatory systems especially when the electric charges of ion and functional groups have different signs.

  17. Large impact of reorganization energy on photovoltaic conversion due to interfacial charge-transfer transitions.

    Fujisawa, Jun-ichi

    2015-05-14

    Interfacial charge-transfer (ICT) transitions are expected to be a novel charge-separation mechanism for efficient photovoltaic conversion featuring one-step charge separation without energy loss. Photovoltaic conversion due to ICT transitions has been investigated using several TiO2-organic hybrid materials that show organic-to-inorganic ICT transitions in the visible region. In applications of ICT transitions to photovoltaic conversion, there is a significant problem that rapid carrier recombination is caused by organic-inorganic electronic coupling that is necessary for the ICT transitions. In order to solve this problem, in this work, I have theoretically studied light-to-current conversions due to the ICT transitions on the basis of the Marcus theory with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. An apparent correlation between the reported incident photon-to-current conversion efficiencies (IPCE) and calculated reorganization energies was clearly found, in which the IPCE increases with decreasing the reorganization energy consistent with the Marcus theory in the inverted region. This activation-energy dependence was systematically explained by the equation formulated by the Marcus theory based on a simple excited-state kinetic scheme. This result indicates that the reduction of the reorganization energy can suppress the carrier recombination and enhance the IPCE. The reorganization energy is predominantly governed by the structural change in the chemical-adsorption moiety between the ground and ICT excited states. This work provides crucial knowledge for efficient photovoltaic conversion due to ICT transitions. PMID:25892453

  18. Heavy Inertial Confinement Energy: Interactions Involoving Low charge State Heavy Ion Injection Beams

    DuBois, Robert D

    2006-04-14

    During the contract period, absolute cross sections for projectile ionization, and in some cases for target ionization, were measured for energetic (MeV/u) low-charge-state heavy ions interacting with gases typically found in high and ultra-high vacuum environments. This information is of interest to high-energy-density research projects as inelastic interactions with background gases can lead to serious detrimental effects when intense ion beams are accelerated to high energies, transported and possibly confined in storage rings. Thus this research impacts research and design parameters associated with projects such as the Heavy Ion Fusion Project, the High Current and Integrated Beam Experiments in the USA and the accelerator upgrade at GSI-Darmstadt, Germany. Via collaborative studies performed at GSI-Darmstadt, at the University of East Carolina, and Texas A&M University, absolute cross sections were measured for a series of collision systems using MeV/u heavy ions possessing most, or nearly all, of their bound electrons, e.g., 1.4 MeV/u Ar{sup +}, Xe{sup 3+}, and U{sup 4,6,10+}. Interactions involving such low-charge-state heavy ions at such high energies had never been previously explored. Using these, and data taken from the literature, an empirical model was developed for extrapolation to much higher energies. In order to extend our measurements to much higher energies, the gas target at the Experimental Storage Ring in GSI-Darmstadt was used. Cross sections were measured between 20 and 50 MeV/u for U{sup 28+}- H{sub 2} and - N{sub 2}, the primary components found in high and ultra-high vacuum systems. Storage lifetime measurements, information inversely proportional to the cross section, were performed up to 180 MeV/u. The lifetime and cross section data test various theoretical approaches used to calculate cross sections for many-electron systems. Various high energy density research projects directly benefit by this information. As a result, the general

  19. Glucose Repression of Fbp1 Transcription in Schizosaccharomyces Pombe Is Partially Regulated by Adenylate Cyclase Activation by a G Protein α Subunit Encoded by Gpa2 (Git8)

    Nocero, M.; Isshiki, T.; Yamamoto, M.; Hoffman, C. S.

    1994-01-01

    In the fission yeast Schizosaccharomyces pombe, genetic studies have identified genes that are required for glucose repression of fbp1 transcription. The git2 gene, also known as cyr1, encodes adenylate cyclase. Adenylate cyclase converts ATP into the second messenger cAMP as part of many eukaryotic signal transduction pathways. The git1, git3, git5, git7, git8 and git10 genes act upstream of adenylate cyclase, presumably encoding an adenylate cyclase activation pathway. In mammalian cells, a...

  20. Energy dependence of the transverse momentum distributions of charged particles in pp collisions measured by ALICE

    Abelev, B.; Adam, J.; Adamová, Dagmar; Bielčíková, Jana; Kushpil, Svetlana; Kushpil, Vasilij; Mareš, Jiří A.; Šumbera, Michal; Vajzer, Michal; Závada, Petr

    2013-01-01

    Roč. 73, č. 12 (2013), s. 1-12. ISSN 1434-6044 R&D Projects: GA MŠk(CZ) LG13031 Institutional support: RVO:68378271 ; RVO:61389005 Keywords : energy dependence * transverse momentum * momentum spectrum * charged particle * p p * scattering Subject RIV: BF - Elementary Particles and High Energy Physics; BG - Nuclear, Atomic and Molecular Physics, Colliders (UJF-V) Impact factor: 5.436, year: 2013 http://link.springer.com/article/10.1140%2Fepjc%2Fs10052-013-2662-9

  1. Beam energy dependence of charged pion ratio in $^{28}$Si + In reactions

    Sako, M; Nakai, Y; Ichikawa, Y; Ieki, K; Imajo, S; Isobe, T; Matsushita, M; Murata, J; Nishimura, S; Sakurai, H; Sameshima, R D; Takada, E

    2014-01-01

    The double differential cross sections for $^{nat}$In($^{28}$Si, $\\pi ^{\\pm}$) reactions are measured at 400, 600, and 800 MeV/nucleon. Both $\\pi^+$ and $\\pi^-$ are found to be emitted isotropically from a single moving source. The $\\pi^- / \\pi^+$ yield ratio is determined as a function of the charged pion energy between 25 and 100 MeV. The experimental results significantly differ from the prediction of the standard transport model calculation using the code PHITS. This discrepancy suggests that more theoretical works are required to deduce firm information on the nuclear symmetry energy from the $\\pi^- / \\pi^+$ yield ratio.

  2. Effects of dark energy on P-V criticality of charged AdS black holes

    Li, Gu-Qiang

    2014-01-01

    In this Letter, we investigate the effects of dark energy on $P-V$ criticality of charged AdS black holes by considering the case of the RN-AdS black holes surrounded by quintessence. By treating the cosmological constant as thermodynamic pressure, we study its thermodynamics in the extended phase space. It is shown that quintessence dark energy does not affect the existence of small/large black hole phase transition. For the case $\\omega_q=-2/3$ we derive analytic expressions of critical phy...

  3. Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus

    1. The effect of melatonin on forskolin-stimulated adenylate cyclase activity was measured in homogenates of Syrian hamster hypothalamus. In addition, the saturation binding characteristics of the melatonin receptor ligand, [125I]iodomelatonin, was examined using an incubation temperature (30 degree C) similar to that used in enzyme assays. 2. At concentrations ranging from 10 pM to 1 nM, melatonin caused a significant decrease in stimulated adenylate cyclase activity with a maximum inhibition of approximately 22%. 3. Binding experiments utilizing [125I]iodomelatonin in a range of approximately 5-80 pM indicated a single class of high-affinity sites: Kd = 55 +/- 9 pM, Bmax = 1.1 +/- 0.3 fmol/mg protein. 4. The ability of picomolar concentrations of melatonin to inhibit forskolin-stimulated adenylate cyclase activity suggests that this affect is mediated by picomolar-affinity receptor binding sites for this hormone in the hypothalamus

  4. Swarm Intelligence-Based Smart Energy Allocation Strategy for Charging Stations of Plug-In Hybrid Electric Vehicles

    Imran Rahman; Pandian M. Vasant; Balbir Singh Mahinder Singh; Abdullah-Al-Wadud, M.

    2015-01-01

    Recent researches towards the use of green technologies to reduce pollution and higher penetration of renewable energy sources in the transportation sector have been gaining popularity. In this wake, extensive participation of plug-in hybrid electric vehicles (PHEVs) requires adequate charging allocation strategy using a combination of smart grid systems and smart charging infrastructures. Daytime charging stations will be needed for daily usage of PHEVs due to the limited all-electric range....

  5. Special charges related to household energy use. Documentations 1970-2012; Saeravgifter relatert til husholdningenes energiforbruk

    Wessmann, Sandra; Halvorsen, Bente; Larsen, Bodil M.

    2012-11-15

    This paper provides an overview of special charges related to household energy use in Norway from 1970 to 2012. Excise duties are presented by the object they apply (rather than to describe the fee arrangements separately). Moreover, they are categorized into three groups: tax on stationary energy, taxes on mobile purposes relating to the ownership and usage-dependent charges on mobile applications. Chapter 2 collects taxes in the first category. The author describes the special taxes imposed on households' stationary energy, such as heating the home. Chapter 3 discusses the various fees imposed on the owner of the vehicle, and how these fees are independent of the amount of transport used. Chapter 4 describes the history of usage-dependent charges on mobile purposes, which include taxes on fuel. This paper is intended to be an encyclopedia for use in future analyzes of the Special Tax behavioral effects in Norwegian households. It is first and foremost in the project households respond to energy and environmental policy measures, funded by the Research Council of the project is not only to look at the excise taxes separately but also how various energy and environmental policy instruments work together. This is one of the reasons for the division of special taxes that have been made in the note. Household energy use contributes to a significant proportion of greenhouse gas emissions and a reduction in household energy consumption is an important goal of climate policy. A number of policy instruments have been eager cat to move household energy consumption away from fossil fuels to renewable energy and increase energy efficiency in Norwegian homes. To ensure the effectiveness of current and future policies, and minimize adverse behavioral effects, information from analyzes of several means changing household adaptation would be of great importance. Project Support: The work of this paper is funded within the Research Council Renergie program (project {sup H

  6. Beam energy dependence of pseudorapidity distributions of charged particles produced in relativistic heavy-ion collisions

    Basu, Sumit; Nayak, Tapan K.; Datta, Kaustuv

    2016-06-01

    Heavy-ion collisions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider at CERN probe matter at extreme conditions of temperature and energy density. Most of the global properties of the collisions can be extracted from the measurements of charged-particle multiplicity and pseudorapidity (η ) distributions. We have shown that the available experimental data on beam energy and centrality dependence of η distributions in heavy-ion (Au +Au or Pb +Pb ) collisions from √{sNN}=7.7 GeV to 2.76 TeV are reasonably well described by the AMPT model, which is used for further exploration. The nature of the η distributions has been described by a double Gaussian function using a set of fit parameters, which exhibit a regular pattern as a function of beam energy. By extrapolating the parameters to a higher energy of √{sNN}=5.02 TeV, we have obtained the charged-particle multiplicity densities, η distributions, and energy densities for various centralities. Incidentally, these results match well with some of the recently published data by the ALICE Collaboration.

  7. Transverse energy distribution, charged particle multiplicities and spectra in 16O-nucleus collisions

    The HELIOS (High Energy Lepton and Ion Spectrometer) experiment, installed at the CERN Super Proton Synchrotron, proposes to examine in details the physical properties of a state of high energy created in nuclei by ultra-relativistic nucleus-nucleus collisions. It is generally believed that, at high densities or temperatures, a phase transition to a plasma of quark and gluons will occur. The dynamic of the expansion of such a plasma and its subsequent condensation into a hadron gas should markedly affect the composition and momentum distribution of the emerging particles and photons. The HELIOS experimental setup therefore combines 4π calorimetric coverage with measurements of inclusive particle spectra, two particle correlations, low and high mass lepton pairs and photons. The emphasis is placed on transverse energy flow (E/sub T/) measurements with good energy resolution, and the ability to trigger the acquisition of data in a variety of E/sub T/ ranges, thereby selecting the impact parameter or the violence of the collisions. This short note presents HELIOS results, for the most part still preliminary, on 16O-nucleus collisions at the incident energies of 60 and 200 GeV per nucleon. The E/sub T/ distributions from Al, Ag and W targets are discussed and compared to the associated charged particle multiplicities from W. Charged particle and (converted) photon spectra measured with the external magnetic spectrometer are compared for 16O + W and p + W collisions at 200 GeV per nucleon. 5 refs., 7 figs

  8. Photoprotection of reaction centers: thermal dissipation of absorbed light energy vs charge separation in lichens.

    Heber, Ulrich; Soni, Vineet; Strasser, Reto J

    2011-05-01

    During desiccation, fluorescence emission and stable light-dependent charge separation in the reaction centers (RCs) of photosystem II (PSII) declined strongly in three different lichens: in Parmelia sulcata with an alga as the photobiont, in Peltigera neckeri with a cyanobacterium and in the tripartite lichen Lobaria pulmonaria. Most of the decline of fluorescence was caused by a decrease in the quantum efficiency of fluorescence emission. It indicated the activation of photoprotective thermal energy dissipation. Photochemical activity of the RCs was retained even after complete desiccation. It led to light-dependent absorption changes and found expression in reversible increases in fluorescence or in fluorescence quenching. Lowering the temperature changed the direction of fluorescence responses in P. sulcata. The observations are interpreted to show that reversible light-induced increases in fluorescence emission in desiccated lichens indicate the functionality of the RCs of PSII. Photoprotection is achieved by the drainage of light energy to dissipating centers outside the RCs before stable charge separation can take place. Reversible quenching of fluorescence by strong illumination is suggested to indicate the conversion of the RCs from energy conserving to energy dissipating units. This permits them to avoid photoinactivation. On hydration, re-conversion occurs to energy-conserving RCs. PMID:21029105

  9. Accelerating QM/MM free energy calculations: representing the surroundings by an updated mean charge distribution.

    Rosta, Edina; Haranczyk, Maciej; Chu, Zhen T; Warshel, Arieh

    2008-05-01

    Reliable studies of enzymatic reactions by combined quantum mechanical/molecular mechanics (QM(ai)/MM) approaches with an ab initio description of the quantum region presents a major challenge to computational chemists. The main problem is the need for very large computer time to evaluate the QM energy, which in turn makes it extremely challenging to perform proper configurational sampling. One of the most obvious options for accelerating QM/MM simulations is the use of an average solvent potential. In fact, the idea of using an average solvent potential is rather obvious and has implicitly been used in Langevin dipole/QM calculations. However, in the case of explicit solvent models the practical implementations are more challenging, and the accuracy of the averaging approach has not been validated. The present study introduces the average effect of the fluctuating solvent charges by using equivalent charge distributions, which are updated every m steps. Several models are evaluated in terms of the resulting accuracy and efficiency. The most effective model divides the system into an inner region with N explicit solvent atoms and an external region with two effective charges. Different models are considered in terms of the division of the solvent system and the update frequency. Another key element of our approach is the use of the free energy perturbation (FEP) and/or linear response approximation treatments that guarantees the evaluation of the rigorous solvation free energy. Special attention is paid to the convergence of the calculated solvation free energies and the corresponding solute polarization. The performance of the method is examined by evaluating the solvation of a water molecule and a formate ion in water and also the dipole moment of water in water solution. Remarkably, it is found that different averaging procedures eventually converge to the same value but some protocols provide optimal ways of obtaining the final QM(ai)/MM converged results. The

  10. Emittance growth in displaced, space-charge-dominated beams with energy spread

    Barnard, J.J.; Miller, J. (Lawrence Livermore National Lab., CA (United States)); Haber, I. (Naval Research Lab., Washington, DC (United States))

    1993-05-11

    Conversion of transverse energy associated with the coherent motion of displaced beams into thermal energy, and thus emittance growth, has been predicted theoretically by a number of authors. Here, they authors show, using 2-D particle-in-cell simulations, that emittance growth is inhibited for tune depressed beams, if the energy spread of the beam is not too large. Further, using a uniform density model to calculate the space charge field of the beam, they numerically determine the criteria for emittance growth as a function of tune depression, energy spread, and beam displacement over a wide range of parameters. A theoretical interpretation of the results is presented. This study is applicable to an inertial fusion reactor driven by a heavy ion accelerator.

  11. Emittance growth in displaced, space-charge-dominated beams with energy spread

    Conversion of transverse energy associated with the coherent motion of displaced beams into thermal energy, and thus emittance growth, has been predicted theoretically by a number of authors. Here, they authors show, using 2-D particle-in-cell simulations, that emittance growth is inhibited for tune depressed beams, if the energy spread of the beam is not too large. Further, using a uniform density model to calculate the space charge field of the beam, they numerically determine the criteria for emittance growth as a function of tune depression, energy spread, and beam displacement over a wide range of parameters. A theoretical interpretation of the results is presented. This study is applicable to an inertial fusion reactor driven by a heavy ion accelerator

  12. Emittance growth in displaced, space-charge-dominated beams with energy spread

    Barnard, J. J.; Miller, J.; Haber, I.

    1993-05-01

    Conversion of transverse energy associated with the coherent motion of displaced beams into thermal energy, and thus emittance growth, has been predicted theoretically by a number of authors. Here, they authors show, using 2-D particle-in-cell simulations, that emittance growth is inhibited for tune depressed beams, if the energy spread of the beam is not too large. Further, using a uniform density model to calculate the space charge field of the beam, they numerically determine the criteria for emittance growth as a function of tune depression, energy spread, and beam displacement over a wide range of parameters. A theoretical interpretation of the results is presented. This study is applicable to an inertial fusion reactor driven by a heavy ion accelerator.

  13. Binding energy correction for atomic L-shell ionization by heavy charged particles

    During the process of inner shell ionization of atoms by low-velocity heavy charged particles the effective binding energy of the target electron is changed due to the presence of the incoming projectile. In the present work the binding energy corrections for the ionization of 2s and 2p sub-shells of the target atom have been calculated by employing approximate expressions for L-shell ionization based on a semi-classical approximation (SCA). The binding energy correction thus obtained has been incorporated in the classical binary encounter theory of ionization to calculate the L-shell ionization cross section of argon by the impact of low energy (50-200keV) protons. The results are compared with the available experimental data. (Auth.)

  14. Effects of dark energy on P–V criticality of charged AdS black holes

    In this Letter, we investigate the effects of dark energy on P–V criticality of charged AdS black holes by considering the case of the RN-AdS black holes surrounded by quintessence. By treating the cosmological constant as thermodynamic pressure, we study its thermodynamics in the extended phase space. It is shown that quintessence dark energy does not affect the existence of small/large black hole phase transition. For the case ωq=−2/3 we derive analytic expressions of critical physical quantities, while for cases ωq≠−2/3 we appeal to numerical method for help. It is shown that quintessence dark energy affects the critical physical quantities near the critical point. Critical exponents are also calculated. They are exactly the same as those obtained before for arbitrary other AdS black holes, which implies that quintessence dark energy does not change the critical exponents

  15. Azimuthally Integrated HBT Parameters for Charged Pions in Nucleus-Nucleus Interactions versus Collision Energy

    The energy dependence of spatiotemporal characteristics of particle emission region is studied for charged pions produced in nuclear collisions. No dramatic change is observed for the HBT parameters with increasing of the center-of-mass (c.m.) energy per nucleon-nucleon pair, √(sNN), for √(sNN) of a few GeV to a few TeV. The emission duration is obtained to be almost independent of the c.m. energy within the measurement uncertainties. The analytic function is suggested for a smooth approximation of the energy dependence of the main HBT parameters. The fits demonstrate reasonable agreement with the experimental data. Predictions are made for future LHC and FCC experiments

  16. Aprataxin resolves adenylated RNA-DNA junctions to maintain genome integrity

    Tumbale, Percy; Williams, Jessica S.; Schellenberg, Matthew J.; Kunkel, Thomas A.; Williams, R Scott

    2013-01-01

    Faithful maintenance and propagation of eukaryotic genomes is ensured by three-step DNA ligation reactions employed by ATP-dependent DNA ligases 1,2 . Paradoxically, when DNA ligases encounter nicked DNA structures with abnormal DNA termini, DNA ligase catalytic activity can generate and/or exacerbate DNA damage through abortive ligation that produces chemically adducted, toxic 5′-adenylated (5′-AMP) DNA lesions 3–6 (Fig. 1a). Aprataxin (Aptx) reverses DNA-adenylation but the context for dead...

  17. The polymerization of amino acid adenylates on sodium-montmorillonite with preadsorbed polypeptides

    Paecht-Horowitz, Mella; Eirich, Frederick R.

    1988-01-01

    The spontaneous polymerization of amino acid adenylates on Na-montmorillonite in dilute, neutral suspension, after polypeptides were adsorbed on the clay, is studied. It is found that the degrees of polymerization of the oligopeptides and polypeptides obtained is dependent on the amounts of polypeptides that were preadsorbed. It is concluded that a catalytic activity may derive from c-spacings that offer adsorption sites for the reagent amino acid adenylate within the peripheral recesses of irregularly stacked clay platelets by bringing the anhydride bonds and neutral amino groups into favorable reaction distances.

  18. Activation of the Pacidamycin PacL Adenylation Domain by MbtH-Like Proteins†

    Zhang, Wenjun; Heemstra, John R.; Walsh, Christopher T.; Imker, Heidi J.

    2010-01-01

    Nonribosomal peptide synthetase (NRPS) assembly lines are major avenues for the biosynthesis of a vast array of peptidyl natural products. Several hundred bacterial NRPS gene clusters contain a small (~70 residue) protein belonging to the MbtH family for which no function has been defined. Here we show that two strictly conserved Trp residues in MbtH-like proteins contribute to stimulation of amino acid adenylation in some NRPS modules. We also demonstrate that adenylation can be stimulated not only by cognate MbtH-like proteins but also by homologues from disparate natural product pathways. PMID:20964365

  19. Activation of the pacidamycin PacL adenylation domain by MbtH-like proteins.

    Zhang, Wenjun; Heemstra, John R; Walsh, Christopher T; Imker, Heidi J

    2010-11-23

    Nonribosomal peptide synthetase (NRPS) assembly lines are major avenues for the biosynthesis of a vast array of peptidyl natural products. Several hundred bacterial NRPS gene clusters contain a small (∼70-residue) protein belonging to the MbtH family for which no function has been defined. Here we show that two strictly conserved Trp residues in MbtH-like proteins contribute to stimulation of amino acid adenylation in some NRPS modules. We also demonstrate that adenylation can be stimulated not only by cognate MbtH-like proteins but also by homologues from disparate natural product pathways. PMID:20964365

  20. Beam energy dependence of pseudorapidity distributions of charged particles produced in heavy-ion collisions at RHIC and LHC energies

    Basu, Sumit; Datta, Kaustuv

    2016-01-01

    Heavy-ion collisions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider at CERN probe matter at extreme conditions of temperature and energy density. Most of the global properties of the collisions can be extracted from the measurements of charged particle multiplicity and pseudorapidity ($\\eta$) distributions. We have shown that the available experimental data on beam energy and centrality dependence of \\Eta-distributions in heavy-ion (Au+Au or Pb+Pb) collisions from \\sNN=7.7 GeV to 2.76 TeV are reasonably well described by the AMPT model, which is used for further exploration. The nature of the \\Eta-distributions has been described by a double Gaussian function using a set of fit parameters, which exhibit a regular pattern as a function of beam energy. By extrapolating the parameters to a higher energy of \\sNN~=~5.02 TeV, we have obtained the charged particle multiplicity densities, \\Eta-distributions and energy densities for various centralities. Incident...

  1. Flexible Local Load Controller for Fast ElectricVehicle Charging Station Supplemented with Flywheel Energy Storage System

    Dragicevic, Tomislav; SUN, BO; Schaltz, Erik;

    2014-01-01

    dedicated flywheel energy storage system (FESS) within the charging station and compensating some of the adverse effects of high power charging is explored in this paper. Although sharing some similarities with vehicle to grid (V2G) technology, the principal advantage of this strategy is the fact that many...

  2. Low-Energy Charge Transfer in Multiply-Charged Ion-Atom Collisions Studied with the Combined SCVB-MOCC Approach

    B. Zygelman

    2002-03-01

    Full Text Available A survey of theoretical studies of charge transfer involving collisions of multiply-charged ions with atomic neutrals (H and He is presented. The calculations utilized the quantum-mechanical molecular-orbital close-coupling (MOCC approach where the requisite potential curves and coupling matrix elements have been obtained with the spin-coupled valence bond (SCVB method. Comparison is made among various collision partners, for equicharged systems, where it is illustrated that even for total charge transfer cross sections, scaling-laws do not exist for low-energy collisions (i.e. < 1 keV/amu. While various empirical scaling-laws are well known in the intermediateand high-energy regimes, the multi-electron configurations of the projectile ions results in a rich and varied low-energy dependence, requiring an explicit calculation for each collision-partner pair. Future charge transfer problems to be addressed with the combined SCVB-MOCC approach are briefly discussed.

  3. Study of Charge Diffusion in a Silicon Detector Using an Energy Sensitive Pixel Readout Chip

    Schioppa, E. J.; van Beuzekom, M.; Visser, J.; Koffeman, E.; Heijne, E.; Engel, K. J.; Uher, J.

    2015-01-01

    A 300 μm thick thin p-on-n silicon sensor was connected to an energy sensitive pixel readout ASIC and exposed to a beam of highly energetic charged particles. By exploiting the spectral information and the fine segmentation of the detector, we were able to measure the evolution of the transverse profile of the charge carriers cloud in the sensor as a function of the drift distance from the point of generation. The result does not rely on model assumptions or electric field calculations. The data are also used to validate numerical simulations and to predict the detector spectral response to an X-ray fluorescence spectrum for applications in X-ray imaging.

  4. Fundamental Studies of Charge Migration and Delocalization Relevant to Solar Energy Conversion

    Michael J. Therien

    2012-06-01

    This program aimed to understand the molecular-level principles by which complex chemical systems carry out photochemical charge separation, transport, and storage, and how these insights could impact the design of practical solar energy conversion and storage devices. Towards these goals, this program focused on: (1) carrying out fundamental mechanistic and transient dynamical studies of proton-coupled electron-transfer (PCET) reactions; (2) characterizing and interrogating via electron paramagnetic resonance (EPR) spectroscopic methods novel conjugated materials that feature large charge delocalization lengths; and (3) exploring excitation delocalization and migration, as well as polaron transport properties of meso-scale assemblies that are capable of segregating light-harvesting antennae, nanoscale wire-like conduction elements, and distinct oxidizing and reducing environments.

  5. Charge collection efficiency degradation on Si diodes irradiated with high energy protons

    Garcia Lopez, J., E-mail: fjgl@us.es [CNA (U. Sevilla, J. Andalucia, CSIC), Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Dpto. Física Atómica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Jimenez-Ramos, M.C. [CNA (U. Sevilla, J. Andalucia, CSIC), Av. Thomas A. Edison 7, 41092 Sevilla (Spain)

    2014-08-01

    The charge collection efficiency (CCE) of several p-type Si diodes has been determined by the Ion Beam Induced Charge (IBIC) technique with 4 MeV protons. In addition, the time evolution of the collected carriers has been recorded as a function of the reverse bias voltage. The diodes were irradiated in our cyclotron with 17 MeV protons and fluences ranging from 3.3 × 10{sup 11} to 1.65 × 10{sup 13} p/cm{sup 2}. The high energy irradiation was selected because of the practically constant value of the proton stopping power across the samples, leading to a uniform vacancy profile with depth. It is observed that the CEE decreases linearly with radiation fluence while the leakage current increases with ion dose. From these results, the diffusion length of minority carriers, the damage constant and the damage coefficient of p-type Si diodes have been evaluated.

  6. Charge collection efficiency degradation on Si diodes irradiated with high energy protons

    The charge collection efficiency (CCE) of several p-type Si diodes has been determined by the Ion Beam Induced Charge (IBIC) technique with 4 MeV protons. In addition, the time evolution of the collected carriers has been recorded as a function of the reverse bias voltage. The diodes were irradiated in our cyclotron with 17 MeV protons and fluences ranging from 3.3 × 1011 to 1.65 × 1013 p/cm2. The high energy irradiation was selected because of the practically constant value of the proton stopping power across the samples, leading to a uniform vacancy profile with depth. It is observed that the CEE decreases linearly with radiation fluence while the leakage current increases with ion dose. From these results, the diffusion length of minority carriers, the damage constant and the damage coefficient of p-type Si diodes have been evaluated

  7. Energy loss of tens keV charged particles traveling in the hot dense carbon plasma

    Fu, ZhenGuo; Wang, ZhiGang; He, Bin; Li, DaFang; Zhang, Ping

    2016-08-01

    The energy loss of charged particles, including electrons, protons, and α-particles with tens keV initial energy E 0, traveling in the hot dense carbon (C) plasma for densities from 2.281 to 22.81 g/cm3 and temperatures from 400 to 1500 eV is systematically and quantitatively studied by using the dimensional continuation method. The behaviors of different charged particles are readily distinguishable from each other. Firstly, because an ion is thousands times heavier than an electron, the penetration distance of the electron is much longer than that of proton and α-particle traveling in the plasma. Secondly, most energy of electron projectile with E 0 < 100 keV deposits into the electron species of C plasma, while for the cases of proton and α-particle with E 0 < 100 keV, about more than half energy transfers into the ion species of C plasma. A simple decreasing law of the penetration distance as a function of the plasma density is fitted, and different behaviors of each projectile particle can be clearly found from the fitted data. We believe that with the advanced progress of the present experimental technology, the findings shown here could be confirmed in ion-stopping experiments in the near future.

  8. Stochastic optimal charging of electric-drive vehicles with renewable energy

    The paper presents the stochastic optimization algorithm that may eventually be used by electric energy suppliers to coordinate charging of electric-drive vehicles (EDVs) in order to maximize the use of renewable energy in transportation. Due to the stochastic nature of transportation patterns, the Monte Carlo simulation is applied to model uncertainties presented by numerous scenarios. To reduce the problem complexity, the simulated driving patterns are not individually considered in the optimization but clustered into fleets using the GAMS/SCENRED tool. Uncertainties of production of renewable energy sources (RESs) are presented by statistical central moments that are further considered in Hong’s 2-point + 1 estimation method in order to define estimate points considered in the optimization. Case studies illustrate the application of the proposed optimization in achieving maximal exploitation of RESs in transportation by EDVs. -- Highlights: ► Optimization model for EDV charging applying linear programming. ► Formation of EDV fleets based on the driving patterns assessment applying the GAMS/SCENRED. ► Consideration of uncertainties of RES production and energy prices in the market. ► Stochastic optimization. ► Application of Hong’s 2-point + 1 estimation method.

  9. An edge-on charge-transfer design for energy-resolved x-ray detection

    Shi, Zaifeng; Yang, Haoyu; Cong, Wenxiang; Wang, Ge

    2016-06-01

    As an x-ray beam goes through the human body, it will collect important information via interaction with tissues. Since this interaction is energy-sensitive, the state-of-the-art spectral CT technologies provide higher quality images of biological tissues with x-ray energy information (or spectral information). With existing energy-integrating technologies, a large fraction of energy information is ignored in the x-ray detection process. Although the recently proposed photon-counting technology promises to achieve higher image quality at a lower radiation dose, it suffers from limitations in counting rate, performance uniformity, and fabrication cost. In this paper, we focus on an alternative approach to resolve the energy distribution of transmitted x-ray photons. First, we analyze the x-ray attenuation in a silicon substrate and describe a linear approximation model for x-ray detection. Then, we design an edge-on architecture based on the proposed energy-resolving model. In our design, the x-ray-photon-induced charges are transferred sequentially resembling the working process of a CCD camera. Finally, we numerically evaluate the linear approximation of x-ray attenuation and derive the energy distribution of x-ray photons. Our simulation results show that the proposed energy-sensing approach is feasible and has the potential to complement the photon-counting technology.

  10. Bordetella adenylate cyclase toxin: a unique combination of a pore-forming moiety with a cell-invading adenylate cyclase enzyme

    Mašín, Jiří; Osička, Radim; Bumba, Ladislav; Šebo, Peter

    2015-01-01

    Roč. 73, č. 8 (2015). ISSN 2049-632X R&D Projects: GA ČR GAP302/12/0460; GA ČR GA15-09157S; GA ČR(CZ) GA15-11851S Institutional support: RVO:61388971 Keywords : adenylate cyclase toxin * membrane penetration * pore-formation Subject RIV: EE - Microbiology, Virology Impact factor: 2.403, year: 2014

  11. Dependence of the hormonal stimulation of adenylate cyclase on the fraction of the plasma membrane accessible for lateral displacement of proteins of the adenylate cyclase complex

    Hormonal activation of the adenylate cyclase complex is associated with lateral displacement in the membrane of the proteins that constitute this complex. In this work an experimental investigation was made of the changes in the interaction of the proteins of the adenylate cyclase complex with the changing fraction of fluid lipids in the cell membrane. A decrease in the fraction of fluid lipids of rat reticulocyte membranes led to a decrease (all the way down to a total suppression) of the interaction of the β-adrenoreceptors with the regulatory N-proteins. The interaction of the N-proteins with the catalytic proteins was also suppressed. On the other hand, an increase in the fraction of fluid lipids led to more effective interaction. It was shown that in this case the functional intactness of the interacting proteins is unimpaired. An analysis of the results obtained, performed on the basis of the percolation theory, suggests the conclusion that the hormonal stimulation of adenylate cyclase depends on the fraction of fluid lipids in the membrane, and the proteins are displaced during interaction over distances comparable with the size of the membrane itself. It was also shown that characteristic activity of the β-agonist 1-isoproterenol varies from 1.0 to 0, depending on the fraction of fluid lipids in the membrane. The data obtained suggest that in the absence of guanylic nucleotides in the membrane in vitro there are no preexisting complexes with a high affinity for the agonist

  12. Modeling and Control of Flexible HEV Charging Station upgraded with Flywheel Energy Storage

    Dragicevic, Tomislav; Shafiee, Qobad; Wu, Dan;

    2014-01-01

    This paper deals with the design of a fast DC charging station (FCS) for hybrid electric vehicles (HEVs) that is connected at a remote location. Power rating of this new technology can go up to a hundred kW and it represents a main challenge for its broad acceptance in distribution systems. In that...... sense, growing number of these stations, if operated in a nonflexible regime, will start to cause problems in future distribution systems such as overloads of local network’s corridors and reduction of its total equivalent spinning reserves. A power balancing strategy based on a local energy storage...... system (ESS) is proposed in this paper. Flywheel has been selected as the means of storing energy as it provides high power density and does not have significant performance degradation along its lifetime. Implemented control algorithm uses the energy stored in flywheel to compensate for the peak of...

  13. Pair Production of Majorana Neutrinos by Annihilation of Charged Particles in High Energy Collision

    Goh, Young Moon; Paeng, Won-Gi; Yoon, Yongsung

    2013-01-01

    Assuming that neutrinos have non-vanishing magnetic moments, we discuss the possibility of pair production through annihilation of charged fermions in high-energy collisions. Adopting the Pauli interaction for photon-neutrino coupling, we calculate the neutrino pair production cross section in the photon channel and compare the result with the standard model in $ Z^{0} $ channel. we demonstrated that the enhancement of the production rate for Majorana neutrino pairs over the standard model rate can be possible at the center-of-mass energy of $10 - 100$ TeV for the Large Hadron Collider or the ultra-high-energy cosmic Ray when the transition magnetic moment is not smaller than $10^{-9} - 10^{-10} \\mu_B$.

  14. Scaling of the transition temperature of hole-doped cuprate superconductors with the charge-transfer energy

    Weber, Cédric; Yee, Chuck-Hou; Haule, Kristjan; Kotliar, Gabriel

    2011-01-01

    We use first-principles calculations to extract two essential microscopic parameters, the charge-transfer energy and the inter-cell oxygen-oxygen hopping, which correlate with the maximum superconducting transition temperature $\\Tcmax$ across the cuprates. We explore the superconducting state in the three-band model of the copper-oxygen planes using cluster Dynamical Mean-Field Theory. We find that the variation in the charge-transfer energy largely accounts for the empirical trend in $\\Tcmax...

  15. Initial Energy Logistics Cost Analysis for Stationary, Quasi-Dynamic, and Dynamic Wireless Charging Public Transportation Systems

    Young Jae Jang

    2016-06-01

    Full Text Available This paper presents an initial investment cost analysis of public transportation systems operating with wireless charging electric vehicles (EVs. There are three different types of wireless charging systems, namely, stationary wireless charging (SWC, in which charging happens only when the vehicle is parked or idle, quasi-dynamic wireless charging (QWC, in which power is transferred when a vehicle is moving slowly or in stop-and-go mode, and dynamic wireless charging (DWC, in which power can be supplied even when the vehicle is in motion. This analysis compares the initial investment costs for these three types of charging systems for a wireless charging-based public transportation system. In particular, this analysis is focused on the energy logistics cost in transportation, which is defined as the cost of transferring and storing the energy needed to operate the transportation system. Performing this initial investment analysis is complicated, because it involves considerable tradeoffs between the costs of batteries in the EV fleet and different kinds of battery-charging infrastructure. Mathematical optimization models for each type of EV and infrastructure system are used to analyze the initial costs. The optimization methods evaluate the minimum initial investment needed to deploy the public transportation system for each type of EV charging solution. To deal with the variable cost estimates for batteries and infrastructure equipment in the current market, a cost-sensitivity analysis is performed. The goal of this analysis is to identify the market cost conditions that are most favorable for each type of wireless charging solution. Furthermore, the cost analysis quantitatively verifies the qualitative comparison of the three different wireless charging types conducted in the previous research.

  16. Influence of argon and oxygen on charge-state-resolved ion energy distributions of filtered aluminum arcs

    Rosen, Johanna; Anders, Andre; Mraz, Stanislav; Atiser, Adil; Schneider, Jochen M.

    2006-01-01

    The charge-state-resolved ion energy distributions (IEDs) in filtered aluminum vacuum arc plasmas were measured and analyzed at different oxygen and argon pressures in the range 0.5 8.0 mTorr. A significant reduction of the ion energy was detected as the pressure was increased, most pronounced in an argon environment and for the higher charge states. The corresponding average charge state decreased from 1.87 to 1.0 with increasing pressure. The IEDs of all metal ions in oxygen were fitte...

  17. HECTOR: a code for the study of high energy charged particles in axisymmetric tokamak plasmas

    A code for the study of high energy charged particles resulting primarily from thermonuclear reactions within the confining magnetic fields of non-circular axisymmetric tokamak plasmas is described. The trajectories of the particles are traced in the (C.O.M.) space using a new, fast, and efficient hybrid orbit following scheme based upon the drift equations in the guiding centre approximation and the constants of motion. The code includes the important Coulomb scattering processes of dynamical friction and pitch angle scattering. The code is specifically designed to operate within the experimental environment or in a predictive mode. (author)

  18. High resolution probe of coherence in low-energy charge exchange collisions with oriented targets

    Leredde, A.; Fléchard, X.; Cassimi, A.; Hennecart, D.; Pons, B.

    2013-01-01

    The trapping lasers of a magneto-optical trap (MOT) are used to bring Rb atoms into well defined oriented states. Coupled to recoil-ion momentum spectroscopy (RIMS), this yields a unique MOTRIMS setup which is able to probe scattering dynamics, including their coherence features, with unprecedented resolution. This technique is applied to the low-energy charge exchange processes Na$^+$+Rb($5p_{\\pm 1}$) $\\rightarrow$ Na($3p,4s$)+Rb$^+$. The measurements reveal detailed features of the collisio...

  19. High resolution probe of coherence in low-energy charge exchange collisions with oriented targets

    Leredde, A; Cassimi, A; Hennecart, D; Pons, B

    2013-01-01

    The trapping lasers of a magneto-optical trap (MOT) are used to bring Rb atoms into well defined oriented states. Coupled to recoil-ion momentum spectroscopy (RIMS), this yields a unique MOTRIMS setup which is able to probe scattering dynamics, including their coherence features, with unprecedented resolution. This technique is applied to the low-energy charge exchange processes Na$^+$+Rb($5p_{\\pm 1}$) $\\rightarrow$ Na($3p,4s$)+Rb$^+$. The measurements reveal detailed features of the collisional interaction which are employed to improve the theoretical description. All of this enables to gauge the reliability of intuitive pictures predicting the most likely capture transitions.

  20. Multiplicity of charged particles in Pb-Pb collisions at SPS energies

    Antinori, F; Badalà, A; Barbera, R; Belogianni, A; Bhasin, A; Bloodworth, Ian J; Bombara, M; Bruno, G; Bull, S A; Caliandro, R; Campbell, M; Carena, W; Carrer, N; Clarke, R F; Dainese, A; De Haas, A P; De Rijke, P C; Di Bari, D; Di Liberto, S; Divià, R; Elia, D; Evans, D; Feofilov, G A; Fini, R A; Ganoti, P; Ghidini, B; Grella, G; Helstrup, H; Hetland, K F; Holme, A K; Jacholkowski, A; Jones, G T; Jovanovic, P; Jusko, A; Kamermans, R; Kinson, J B; Knudson, K; Kolojvari, A A; Kondratiev, V; Králik, I; Kravcakova, A; Kuijer, P; Lenti, V; Lietava, R; Løvhøiden, G; Manzari, V; Martinská, G; Mazzoni, M A; Meddi, F; Michalon, A; Morando, M; Nappi, E; Navach, F; Norman, P I; Palmeri, A; Pappalardo, G S; Pastircák, B; Pisút, J; Pisútová, N; Platt, R J; Posa, F; Quercigh, Emanuele; Riggi, F; Röhrich, D; Romano, G; Safarík, K; Sándor, L; Schillings, E; Segato, G F; Sené, M; Sené, R; Snoeys, W; Soramel, F; Spyropoulou-Stassinaki, M; Staroba, P; Toulina, T A; Turrisi, R; Tveter, T S; Urbán, J; Valiev, F F; Van den Brink, A; Van de Ven, P; Van den Vyvre, P; van Eijndhoven, N; Van Hunen, J J; Vascotto, Alessandro; Vik, T; Villalobos Baillie, O; Vinogradov, L I; Virgili, T; Votruba, M F; Vrláková, J; Závada, P

    2005-01-01

    The multiplicity of charged particles in the central rapidity region has been measured by the NA57 experiment in Pb--Pb collisions at the CERN SPS at two beam momenta: 158 A GeV/{\\it c} and 40 A GeV/{\\it c}. The value of $dN_{ch}/d\\eta$ at the maximum has been determined and its behaviour as a function of centrality has been studied in the centrality range covered by NA57 (about 50% of the inelastic cross section). The multiplicity increases approximately logarithmically with the centre of mass energy.

  1. Deployment of Behind-The-Meter Energy Storage for Demand Charge Reduction

    Neubauer, J.; Simpson, M.

    2015-01-01

    This study investigates how economically motivated customers will use energy storage for demand charge reduction, as well as how this changes in the presence of on-site photovoltaic power generation, to investigate the possible effects of incentivizing increased quantities of behind-the-meter storage. It finds that small, short-duration batteries are most cost effective regardless of solar power levels, serving to reduce short load spikes on the order of 2.5% of peak demand. While profitable to the customer, such action is unlikely to adequately benefit the utility as may be desired, thus highlighting the need for modified utility rate structures or properly structured incentives.

  2. Survival of intestinal crypt cells after exposure to high Z, high energy charged particles

    The purpose of the experiments described is to evaluate the relative biological effectiveness (RBE) of high energy charged particles for cell killing in the mouse crypt-cell survival assay. The reference radiation, 225 kVp x rays, is slightly more effective than plateau helium ions. For carbon, neon and argon ions there is a suggestion of a saturation effect with increasing LET. Furthermore, it should be emphasized that there is a large difference associated with particles of different atomic number or mass at the same average LET

  3. Space charge compensation on the low energy beam transport of Linac4

    AUTHOR|(SzGeCERN)733270; Scrivens, Richard; Jesus Castillo, Santos

    Part of the upgrade program in the injector chains of the CERN accelerator complex is the replacement of the the proton accelerator Linac2 for the brand new Linac4 which will accelerate H$^-$ and its main goal is to increase the beam intensity in the next sections of the LHC accelerator chain. The Linac4 is now under commissioning and will use several ion sources to produce high intensity unbunched H$^-$ beams with different properties, and the low energy beam transport (LEBT) is the system in charge of match all these different beams to the Radio frequency quadrupole (RFQ). The space charge forces that spread the beam ions apart of each other and cause emittance growth limits the maximum intensity that can be transported in the LEBT, but the space charge of intense unbunched ion beams can be compensated by the generated ions by the impact ionization of the residual gas, which creates a source of secondary particles inside the beam pipe. For negative ion beams, the effect of the beam electric field is to ex...

  4. Theoretical and observed potential energy curves for neutral 4-unit charge Coulomb systems containing antihydrogen

    Van Hooydonk, G

    2005-01-01

    Comparing observed and theoretical potential energy curves for natural and exotic neutral 4-unit charge Coulomb systems like HH and HantiH leads to new conclusions on the effect of charge-antisymmetry in nature. With singularities in the HantiH PEC as found by Aldrovandi and Puget and by Junker and Bardsley, any cusp in the HantiH PEC significantly affects the annihilation cross section. This problem for the HantiH interaction generated many new wave mechanical calculations mainly to remove annoying cusps. We review all available PECs for 4-unit charge systems and find that corrections for the Morgan-Hughes HantiH PEC can either go to the repulsive side (to the conventionally expected annihilation channel) or to the opposite attractive side (to the attractive branch of the observed PEC of natural molecular HH). We observe that all theoretical HantiH PECs published thus far would intersect the observed PEC of natural HH. This is, however, impossible with the non-crossing rule. A classical ab initio calculation...

  5. Model calculation of the charge transfer in low-energy He+ scattering from metallic surfaces

    Charge-transfer mechanisms in low-energy helium-scattering spectroscopy are analyzed by using an Anderson-like description of the time-dependent collisional process, which allows us to include several electronic bands of extended and localized nature in the solid. The Hamiltonian parameters are obtained from a Hartree-Fock self-consistent-field calculation of the He-target atom dimeric system. We examine in particular cases such as Ca and Ga linear chain substrates. We found that at velocities large enough, the localized state in the solid contributes to the He+ neutralization, showing the characteristic oscillatory behavior of the nonadiabatic charge exchange between localized states, in agreement with other calculations. In the range of low velocities we found that if the hybridization between the He orbital and the localized states in the solid is able to produce the formation of an antibonding state having a predominant weight of the He-1s orbital, this promotes the charge exchange between the Helium and the extended bandstates of the solid

  6. Modulation of receptors and adenylate cyclase activity during sucrose feeding, food deprivation, and cold exposure

    Thermogenesis in brown adipose tissue (BAT) serves as a regulator of body temperature and weight maintenance. Thermogenesis can be stimulated by catecholamine activation of adenylate cyclase through the β-adrenergic receptor. To investigate the effects of sucrose feeding, food deprivation, and cold exposure on the β-adrenergic pathway, adenylate cyclase activity and β-adrenergic receptors were assessed in rat BAT after 2 wk of sucrose feeding, 2 days of food deprivation, or 2 days of cold exposure. β-Adrenergic receptors were identified in BAT using [125I]iodocyanopindolol. Binding sites had the characteristics of mixed β1- and β2-type adrenergic receptors at a ratio of 60/40. After sucrose feeding or cold exposure, there was the expected increase in BAT mitochondrial mass as measured by total cytochrome-c oxidase activity but a decrease in β-adrenergic receptor density due to a loss of the β1-adrenergic subtype. This BAT β-adrenergic receptor downregulation was tissue specific, since myocardial β-adrenergic receptors were unchanged with either sucrose feeding or cold exposure. Forskolin-stimulated adenylate cyclase activity increased in BAT after sucrose feeding or cold exposure but not after food deprivation. These data suggest that in BAT, sucrose feeding or cold exposure result in downregulation of β-adrenergic receptors and that isoproterenol-stimulated adenylate cyclase activity was limited by receptor availability

  7. Modulation of receptors and adenylate cyclase activity during sucrose feeding, food deprivation, and cold exposure

    Scarpace, P.J.; Baresi, L.A.; Morley, J.E. (Veterans Administration Medical Center, Los Angeles, CA (USA) Univ. of California, Los Angeles (USA))

    1987-12-01

    Thermogenesis in brown adipose tissue (BAT) serves as a regulator of body temperature and weight maintenance. Thermogenesis can be stimulated by catecholamine activation of adenylate cyclase through the {beta}-adrenergic receptor. To investigate the effects of sucrose feeding, food deprivation, and cold exposure on the {beta}-adrenergic pathway, adenylate cyclase activity and {beta}-adrenergic receptors were assessed in rat BAT after 2 wk of sucrose feeding, 2 days of food deprivation, or 2 days of cold exposure. {beta}-Adrenergic receptors were identified in BAT using ({sup 125}I)iodocyanopindolol. Binding sites had the characteristics of mixed {beta}{sub 1}- and {beta}{sub 2}-type adrenergic receptors at a ratio of 60/40. After sucrose feeding or cold exposure, there was the expected increase in BAT mitochondrial mass as measured by total cytochrome-c oxidase activity but a decrease in {beta}-adrenergic receptor density due to a loss of the {beta}{sub 1}-adrenergic subtype. This BAT {beta}-adrenergic receptor downregulation was tissue specific, since myocardial {beta}-adrenergic receptors were unchanged with either sucrose feeding or cold exposure. Forskolin-stimulated adenylate cyclase activity increased in BAT after sucrose feeding or cold exposure but not after food deprivation. These data suggest that in BAT, sucrose feeding or cold exposure result in downregulation of {beta}-adrenergic receptors and that isoproterenol-stimulated adenylate cyclase activity was limited by receptor availability.

  8. Energy loss and charge transfer effects of low energy protons in thin organic films

    Byrne, C M

    2000-01-01

    observed in TRIM simulations. It is possible that this might be attributed to a quasi-channelling effect in the 12-8 PDA at these low energies. Attempts were made to apply the same techniques to the study of thin films of double-stranded DNA. It proved difficult to produce reliable measurements over the considerable lengths of time the samples had to reside in a high vacuum. Energy loss measurements were nevertheless made for some of the DNA films although these, together with the estimates of film thickness, could not be used for any quantitative measurements. The energy loss and stopping power of protons with incident energies between 4.93 and 15 keV has been determined for self-supporting Langmiur-Blodgett films of polymerised 12-8 diacetylene (12-8 PDA), of 54 and 60 nm thicknesses, in a transmission mode. Energy loss as a function of both incident proton energy and energy loss as a function of angle has been determined for the two thicknesses of 12-8 PDA in this energy range and the experimental data com...

  9. Accretion of dark energy onto higher dimensional charged BTZ black hole

    In this work, we have studied the accretion of the (n+2)-dimensional charged BTZ black hole (BH). The critical point and square speed of sound have been obtained. The mass of the BTZ BH has been calculated and we have observed that the mass of the BTZ BH is related with the square root of the energy density of the dark energy which accretes onto the BH in our accelerating FRW universe. We have assumed modified Chaplygin gas (MCG) as a candidate of dark energy which accretes onto the BH and we have found the expression of BTZ BH mass. Since in our solution of MCG, this model generates only quintessence dark energy (not phantom) and so BTZ BH mass increases during the whole evolution of the accelerating universe. Next we have assumed five kinds of parametrizations of well-known dark-energy models. These models generate both quintessence and phantom scenarios i.e., phantom crossing models. So if these dark energies accrete onto the BTZ BH, then in the quintessence stage, the BH mass increases up to a certain value (finite value) and then decreases to a certain finite value for the phantom stage during the whole evolution of the universe. We have shown these results graphically. (orig.)

  10. Accretion of dark energy onto higher dimensional charged BTZ black hole

    Debnath, Ujjal [Indian Institute of Engineering Science and Technology, Department of Mathematics, Howrah (India)

    2015-09-15

    In this work, we have studied the accretion of the (n+2)-dimensional charged BTZ black hole (BH). The critical point and square speed of sound have been obtained. The mass of the BTZ BH has been calculated and we have observed that the mass of the BTZ BH is related with the square root of the energy density of the dark energy which accretes onto the BH in our accelerating FRW universe. We have assumed modified Chaplygin gas (MCG) as a candidate of dark energy which accretes onto the BH and we have found the expression of BTZ BH mass. Since in our solution of MCG, this model generates only quintessence dark energy (not phantom) and so BTZ BH mass increases during the whole evolution of the accelerating universe. Next we have assumed five kinds of parametrizations of well-known dark-energy models. These models generate both quintessence and phantom scenarios i.e., phantom crossing models. So if these dark energies accrete onto the BTZ BH, then in the quintessence stage, the BH mass increases up to a certain value (finite value) and then decreases to a certain finite value for the phantom stage during the whole evolution of the universe. We have shown these results graphically. (orig.)

  11. Adding high time resolution to charge-state-specific ion energy measurements for pulsed copper vacuum arc plasmas

    Tanaka, Koichi; Zhou, Xue; Anders, André

    2015-01-01

    Charge-state-resolved ion energy-time-distributions of pulsed Cu arc plasma were obtained by using direct (time dependent) acquisition of the ion detection signal from a commercial ion mass-per-charge and energy-per-charge analyzer. We find a shift of energies of Cu2+, Cu3+ and Cu4+ ions to lower values during the first few hundred microseconds after arc ignition, which is evidence for particle collisions in the plasma. The generation of Cu1+ ions in the later part of the pulse, measured by the increase of Cu1+ signal intensity and an associated slight reduction of the mean charge state point to charge exchange reactions between ions and neutrals. At the very beginning of the pulse, when the plasma expands into vacuum and the plasma potential strongly fluctuates, ions with much higher energy (over 200 eV) were observed. Early in the pulse, the ion energies observed are approximately proportional to the ion charge state, and we conclude that the acceleration mechanism is primarily based on acceleration in an e...

  12. Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC

    Adamczyk, L; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Sánchez, M Calderón de la Barca; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Leyva, A Davila; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; de Souza, R Derradi; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kosarzewski, L K; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; LeVine, M J; Li, C; Li, W; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Don, D M M D Madagodagettige; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Poniatowska, K; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen,, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-01-01

    Local parity-odd domains are theorized to form inside a Quark-Gluon-Plasma (QGP) which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect (CME). The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this paper, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39 and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy, and tends to vanish by 7.7 GeV. The implications of these results for the CME will be discussed.

  13. Electronic structure, stacking energy, partial charge, and hydrogen bonding in four periodic B-DNA models

    Poudel, Lokendra; Rulis, Paul; Liang, Lei; Ching, W. Y.

    2014-08-01

    We present a theoretical study of the electronic structure of four periodic B-DNA models labeled (AT)10,(GC)10, (AT)5(GC)5, and (AT-GC)5 where A denotes adenine, T denotes thymine, G denotes guanine, and C denotes cytosine. Each model has ten base pairs with Na counterions to neutralize the negative phosphate group in the backbone. The (AT)5(GC)5 and (AT-GC)5 models contain two and five AT-GC bilayers, respectively. When compared against the average of the two pure models, we estimate the AT-GC bilayer interaction energy to be 19.015 Kcal/mol, which is comparable to the hydrogen bonding energy between base pairs obtained from the literature. Our investigation shows that the stacking of base pairs plays a vital role in the electronic structure, relative stability, bonding, and distribution of partial charges in the DNA models. All four models show a highest occupied molecular orbital (HOMO) to lowest unoccupied molecular orbital (LUMO) gap ranging from 2.14 to 3.12 eV with HOMO states residing on the PO4 + Na functional group and LUMO states originating from the bases. Our calculation implies that the electrical conductance of a DNA molecule should increase with increased base-pair mixing. Interatomic bonding effects in these models are investigated in detail by analyzing the distributions of the calculated bond order values for every pair of atoms in the four models including hydrogen bonding. The counterions significantly affect the gap width, the conductivity, and the distribution of partial charge on the DNA backbone. We also evaluate quantitatively the surface partial charge density on each functional group of the DNA models.

  14. Energy-momentum conservation in pre-metric electrodynamics with magnetic charges

    Kaiser, Gerald [Center for Signals and Waves, Austin, TX (United States)

    2004-07-16

    A necessary and sufficient condition for energy-momentum conservation is proved within a topological, pre-metric approach to classical electrodynamics including magnetic as well as electric charges. The extended Lorentz force, consisting of mutual actions by F {approx} (E, B) on the electric current and G {approx} (H, D) on the magnetic current, can be derived from an energy-momentum 'potential' if and only if the constitutive relation G = G(F) satisfies a certain vanishing condition. The electric-magnetic reciprocity introduced by Hehl and Obukhov is shown to define a one-parameter family * {sub z} of complex structures on the product space of 2-form pairs (F, G), independent of any spacetime metric, which reduces to the product of two Hodge star operators once a Lorentzian metric is introduced. In contrast to a recent claim made in the literature, it does not define a complex structure on the space of 2-forms itself.

  15. Dynamic wireless charging of electric vehicles on the move with Mobile Energy Disseminators

    Leandros A. Maglaras

    2015-06-01

    Full Text Available Dynamic wireless charging of electric vehicles (EVs is becoming a preferred method since it enables power exchange between the vehicle and the grid while the vehicle is moving. In this article, we present mobile energy disseminators (MED, a new concept, that can facilitate EVs to extend their range in a typical urban scenario. Our proposed method exploits Inter-Vehicle (IVC communications in order to eco-route electric vehicles taking advantage of the existence of MEDs. Combining modern communications between vehicles and state of the art technologies on energy transfer, vehicles can extend their travel time without the need for large batteries or extremely costly infrastructure. Furthermore, by applying intelligent decision mechanisms we can further improve the performance of the method.

  16. Localized description of surface energy gap effects in the resonant charge exchange between atoms and surfaces

    Iglesias-Garcia, A; Garcia, Evelina A; Goldberg, E C, E-mail: aiglesiasg@santafe-conicet.gov.ar [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC-CONICET-UNL), Gueemes 3450, CC91, (S3000GLN) Santa Fe (Argentina)

    2011-02-02

    The resonant charge exchange between atoms and surfaces is described by considering a localized atomistic view of the solid within the Anderson model. The presence of a surface energy gap is treated within a simplified tight-binding model of the solid, and a proper calculation of the Hamiltonian terms based on a LCAO expansion of the solid eigenstates is performed. It is found that interference terms jointly with a surface projected gap maximum at the {Gamma} point and the Fermi level inside it, lead to hybridization widths negligible around the Fermi level. This result can explain experimental observations related to long-lived adsorbate states and anomalous neutral fractions of low energy ions in alkali/Cu(111) systems.

  17. Supercell convergence of charge-transfer energies in pentacene molecular crystals from constrained DFT

    Turban, David H P; O'Regan, David D; Hine, Nicholas D M

    2016-01-01

    Singlet fission (SF) is a multi-exciton generation process that could be harnessed to improve the efficiency of photovoltaic devices. Experimentally, systems derived from the pentacene molecule have been shown to exhibit ultrafast SF with high yields. Charge-transfer (CT) configurations are likely to play an important role as intermediates in the SF process in these systems. In molecular crystals, electrostatic screening effects and band formation can be significant in lowering the energy of CT states, enhancing their potential to effectively participate in SF. In order to simulate these, it desirable to adopt a computational approach which is acceptably accurate, relatively inexpensive, which and scales well to larger systems, thus enabling the study of screening effects. We propose a novel, electrostatically-corrected constrained Density Functional Theory (cDFT) approach as a low-cost solution to the calculation of CT energies in molecular crystals such as pentacene. Here we consider an implementation in th...

  18. Correlation of Resonance Charge Exchange Cross-Section Data in the Low-Energy Range

    Sheldon, John W.

    1962-01-01

    During the course of a literature survey concerning resonance charge exchange, an unusual degree of agreement was noted between an extrapolation of the data reported by Kushnir, Palyukh, and Sena and the data reported by Ziegler. The data of Kushnir et al. are for ion-atom relative energies from 10 to 1000 ev, while the data of Ziegler are for a relative energy of about 1 ev. Extrapolation of the data of Kushnir et al. was made in accordance with Holstein's theory, 3 which is a combination of time-dependent perturbation methods and classical orbit theory. The results of this theory may be discussed in terms of a critical impact parameter b(sub c).

  19. Localized description of surface energy gap effects in the resonant charge exchange between atoms and surfaces.

    Iglesias-García, A; García, Evelina A; Goldberg, E C

    2011-02-01

    The resonant charge exchange between atoms and surfaces is described by considering a localized atomistic view of the solid within the Anderson model. The presence of a surface energy gap is treated within a simplified tight-binding model of the solid, and a proper calculation of the Hamiltonian terms based on a LCAO expansion of the solid eigenstates is performed. It is found that interference terms jointly with a surface projected gap maximum at the Γ point and the Fermi level inside it, lead to hybridization widths negligible around the Fermi level. This result can explain experimental observations related to long-lived adsorbate states and anomalous neutral fractions of low energy ions in alkali/Cu(111) systems. PMID:21406877

  20. On the Binding Energy and the Charge Symmetry Breaking in A<=16 Lambda-hypernuclei

    Botta, E; Feliciello, A

    2016-01-01

    Recent achievements in hypernuclear spectroscopy, in particular the determination of the $\\Lambda$-binding energy B$_{\\Lambda}$ by high precision magnetic spectrometry, contributed to stimulate considerably the search for Charge Symmetry Breaking effects in $\\Lambda$-hypernuclei isomultiplets. We have reorganized the results from the FINUDA experiment and we have produced a list of B$_{\\Lambda}$ values for hypernuclei with A$\\leq$16 considering only the data from magnetic spectrometers with an absolute calibration of the energy scale (FINUDA at DA$\\Phi$NE and electroproduction experiments). By comparing them with the corresponding B$_{\\Lambda}$ from the emulsion experiments, we observe that there is a systematic small difference that is taken into account. A synopsis of all the results on B$_{\\Lambda}$ so far published is finally suggested. Several interesting conclusions are drawn, among which the equality within the errors of B$_{\\Lambda}$ for the A=7, 12, 16 isomultiplets, based only on recent spectrometri...

  1. Charge transport and activation energy of amorphous silicon carbide thin film on quartz at elevated temperature

    Dinh, Toan; Viet Dao, Dzung; Phan, Hoang-Phuong; Wang, Li; Qamar, Afzaal; Nguyen, Nam-Trung; Tanner, Philip; Rybachuk, Maksym

    2015-06-01

    We report on the temperature dependence of the charge transport and activation energy of amorphous silicon carbide (a-SiC) thin films grown on quartz by low-pressure chemical vapor deposition. The electrical conductivity as characterized by the Arrhenius rule was found to vary distinctly under two activation energy thresholds of 150 and 205 meV, corresponding to temperature ranges of 300 to 450 K and 450 to 580 K, respectively. The a-SiC/quartz system displayed a high temperature coefficient of resistance ranging from -4,000 to -16,000 ppm/K, demonstrating a strong feasibility of using this material for highly sensitive thermal sensing applications.

  2. An Energy- and Charge-conserving, Implicit, Electrostatic Particle-in-Cell Algorithm

    Chen, Guangye; Barnes, Daniel C

    2011-01-01

    This paper discusses a novel fully implicit formulation for a 1D electrostatic particle-in-cell (PIC) plasma simulation approach. Unlike earlier implicit electrostatic PIC approaches (which are based on a linearized Vlasov-Poisson formulation), ours is based on a nonlinearly converged Vlasov-Amp\\`ere (VA) model. By iterating particles and fields to a tight nonlinear convergence tolerance, the approach features superior stability and accuracy properties, avoiding most of the accuracy pitfalls in earlier implicit PIC implementations. In particular, the formulation is stable against temporal (CFL) and spatial (aliasing) instabilities. It is charge- and energy-conserving to numerical roundoff for arbitrary implicit time steps. While momentum is not exactly conserved, errors are kept small by an adaptive particle sub-stepping orbit integrator, which is instrumental to prevent particle tunneling. The VA model is orbit-averaged along particle orbits to enforce an energy conservation theorem with particle sub-steppin...

  3. Enhancing energy recovery in the steel industry: Matching continuous charge with off-gas variability smoothing

    Highlights: • A system based on phase change material is inserted into the off-gas-line of a continuous charge electric arc furnace. • The off-gas temperature profile after scrap preheating is smoothed. • A heat transfer fluid through phase change material containers allows to control overheating issues. • The smoothed off-gas profiles enable efficient downstream power generation. • The recovery system investment cost is decreased due to lower sizes of components. - Abstract: In order to allow an efficient energy recovery from off-gas in the steel industry, the high variability of heat flow should be managed. A temperature smoothing device based on phase change materials at high temperatures is inserted into the off-gas line of a continuous charge electric arc furnace process with scrap preheating. To address overheating issues, a heat transfer fluid flowing through containers is introduced and selected by developing an analytical model. The performance of the smoothing system is analyzed by thermo-fluid dynamic simulations. The reduced maximum temperature of off-gas allows to reduce the size and investment cost of the downstream energy recovery system, while the increased minimum temperature enhances the steam turbine load factor, thus increasing its utilization. Benefits on environmental issues due to dioxins generation are also gained

  4. Effect of functionalization and charging on resonance energy and radial breathing modes of metallic carbon nanotubes

    Öberg, S.; Adjizian, J.-J.; Erbahar, D.; Rio, J.; Humbert, B.; Dossot, M.; Soldatov, A.; Lefrant, S.; Mevellec, J.-Y.; Briddon, P.; Rayson, M. J.; Ewels, C. P.

    2016-01-01

    While changes in resonant Raman scattering measurements are commonly used to measure the effect of chemical functionalization on single-walled carbon nanotubes, the precise effects of functionalization on these spectra have yet to be clearly identified. In this density functional theory study, we explore the effects of functionalization on both the nanotube resonance energy and frequency shifts in radial breathing mode. Charge transfer effects cause a shift in the first Van Hove singularity spacings, and hence resonance excitation energy, and lead to a decrease in the radial breathing mode frequency, notably when the Fermi level decreases. By varying stochastically the effective mass of carbon atoms in the tube, we simulate the mass effect of functionalization on breathing mode frequency. Finally, full density functional calculations are performed for different nanotubes with varying functional group distribution and concentration using fluorination and hydrogenation, allowing us to determine overall effect on radial breathing mode and charge transfer. The results concur well with experiment, and we discuss the importance when using Raman spectroscopy to interpret experimental functionalization treatments.

  5. A closed parameterization of DNA-damage by charged particles as a function of energy

    D, Frank Van den Heuvel Ph

    2013-01-01

    Purpose: To present a closed formalism calculating charged particle radiation damage induced in DNA, based on a simplified molecular model. The formalism is valid for all types of charged particles and due to its closed nature is suited to provide fast conversion of dose to DNA-damage. Methods: The induction of complex DNA--damaged is modelled using the standard scattering theory with a simplified effective potential. This leads to a proposal to use the Breit-Wigner expression to model the probability of the complex damage inelastic scatter as a function of kinetic energy of the scattered particle. A microscopic phenomenological Monte Carlo code is used to predict the damage to a DNA molecule embedded in a cell. The model is fit to the result of the simulation for four particles: electrons, protons, alpha--particles, and Carbon ions. The model is then used to predict the damage in a cell as a function of kinetic energy. Finally, a framework is proposed and implemented to provide data that can be assessed expe...

  6. Studies on low energy beam transport for high intensity high charged ions at IMP

    Yang, Y., E-mail: yangyao@impcas.ac.cn; Lu, W.; Fang, X. [Institute of Modern Physics, CAS, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Sun, L. T.; Hu, Q.; Cao, Y.; Feng, Y. C.; Zhang, X. Z.; Zhao, H. W.; Xie, D. Z. [Institute of Modern Physics, CAS, Lanzhou 730000 (China)

    2014-02-15

    Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 18–24 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110° analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110° analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper.

  7. Studies on low energy beam transport for high intensity high charged ions at IMP.

    Yang, Y; Sun, L T; Hu, Q; Cao, Y; Lu, W; Feng, Y C; Fang, X; Zhang, X Z; Zhao, H W; Xie, D Z

    2014-02-01

    Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 18-24 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110° analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110° analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper. PMID:24593453

  8. Ionization and fragmentation of C60 by highly charged, high-energy xenon ions

    C60 vapor was bombarded by 136Xe35+ and 136Xe18+ ions in the energy range 420 endash 625 MeV to study the various ionization and fragmentation processes that occur. Since the center-of-mass energies used in this work exceeded those of previous studies by several orders of magnitude, new excitation and dissociation modes were expected and indeed found. Positive ions were extracted from the interaction region and their times of flight were measured both singly and in coincidence with other ionic fragments. A wide range of stable charge states and cluster sizes from monatomic carbon up to C60 was observed. Even-numbered carbon fragments dominated the heavier mass range but both even and odd carbon numbers occurred at lower masses. Evidence was found for three qualitatively different ionization and fragmentation channels suggesting different ranges of collision impact parameters: ionization of the parent C60 molecule, loss of even numbers of carbon atoms, and open-quote open-quote multifragmentation close-quote close-quote into many small fragments. This latter mode included the production of singly charged Cn+ fragments with all values of n being observed from n=1 up to at least n=19. We interpret our results in terms of a theoretical model that indicates that the total interaction cross section contains comparable contributions from (a) excitation of the giant dipole plasmon resonance, and (b) large-energy-transfer processes that lead to multiple fragmentation of the molecule. The distribution of fragment cluster masses for n approx-lt 20 is reproduced by a open-quote open-quote percolation theory close-quote close-quote description analogous to that used to describe multifragmentation of nuclei by high-energy protons. copyright 1996 The American Physical Society

  9. Self-regulation of charged defect compensation and formation energy pinning in semiconductors.

    Yang, Ji-Hui; Yin, Wan-Jian; Park, Ji-Sang; Wei, Su-Huai

    2015-01-01

    Current theoretical analyses of defect properties without solving the detailed balance equations often estimate Fermi-level pinning position by omitting free carriers and assume defect concentrations can be always tuned by atomic chemical potentials. This could be misleading in some circumstance. Here we clarify that: (1) Because the Fermi-level pinning is determined not only by defect states but also by free carriers from band-edge states, band-edge states should be treated explicitly in the same footing as the defect states in practice; (2) defect formation energy, thus defect density, could be pinned and independent on atomic chemical potentials due to the entanglement of atomic chemical potentials and Fermi energy, in contrast to the usual expectation that defect formation energy can always be tuned by varying the atomic chemical potentials; and (3) the charged defect compensation behavior, i.e., most of donors are compensated by acceptors or vice versa, is self-regulated when defect formation energies are pinned. The last two phenomena are more dominant in wide-gap semiconductors or when the defect formation energies are small. Using NaCl and CH3NH3PbI3 as examples, we illustrate these unexpected behaviors. Our analysis thus provides new insights that enrich the understanding of the defect physics in semiconductors and insulators. PMID:26584670

  10. Electron energy and charge albedos - calorimetric measurement vs Monte Carlo theory

    A new calorimetric method has been employed to obtain saturated electron energy albedos for Be, C, Al, Ti, Mo, Ta, U, and UO2 over the range of incident energies from 0.1 to 1.0 MeV. The technique was so designed to permit the simultaneous measurement of saturated charge albedos. In the cases of C, Al, Ta, and U the measurements were extended down to about 0.025 MeV. The angle of incidence was varied from 00 (normal) to 750 in steps of 150, with selected measurements at 82.50 in Be and C. In each case, state-of-the-art predictions were obtained from a Monte Carlo model. The generally good agreement between theory and experiment over this extensive parameter space represents a strong validation of both the theoretical model and the new experimental method. Nevertheless, certain discrepancies at low incident energies, especially in high-atomic-number materials, and at all energies in the case of the U energy albedos are not completely understood

  11. Energy Decomposition Analysis with a Stable Charge-Transfer Term for Interpreting Intermolecular Interactions.

    Lao, Ka Un; Herbert, John M

    2016-06-14

    Many schemes for decomposing quantum-chemical calculations of intermolecular interaction energies into physically meaningful components can be found in the literature, but the definition of the charge-transfer (CT) contribution has proven particularly vexing to define in a satisfactory way and typically depends strongly on the choice of basis set. This is problematic, especially in cases of dative bonding and for open-shell complexes involving cation radicals, for which one might expect significant CT. Here, we analyze CT interactions predicted by several popular energy decomposition analyses and ultimately recommend the definition afforded by constrained density functional theory (cDFT), as it is scarcely dependent on basis set and provides results that are in accord with chemical intuition in simple cases, and in quantitative agreement with experimental estimates of the CT energy, where available. For open-shell complexes, the cDFT approach affords CT energies that are in line with trends expected based on ionization potentials and electron affinities whereas some other definitions afford unreasonably large CT energies in large-gap systems, which are sometimes artificially offset by underestimation of van der Waals interactions by density functional theory. Our recommended energy decomposition analysis is a composite approach, in which cDFT is used to define the CT component of the interaction energy and symmetry-adapted perturbation theory (SAPT) defines the electrostatic, polarization, Pauli repulsion, and van der Waals contributions. SAPT/cDFT provides a stable and physically motivated energy decomposition that, when combined with a new implementation of open-shell SAPT, can be applied to supramolecular complexes involving molecules, ions, and/or radicals. PMID:27049750

  12. Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids

    Diederich, Geoffrey; O'Connor, Timothy; Moroz, Pavel; Kinder, Erich; Kohn, Elena; Perera, Dimuthu; Lorek, Ryan; Lambright, Scott; Imboden, Martene; Zamkov, Mikhail

    2012-01-01

    Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials offering a superior control over the spatial distribution of charge carriers across material interfaces. As this study demonstrates, a combination of donor-acceptor nanocrystal (NC) domains in a single nanoparticle can lead to the realization of efficient photocatalytic1-5 materials, while a layered assembly of donor- and acceptor-like nanocrystals films gives rise to photovoltaic materials. Initially the paper focuses on the synthesis of composite inorganic nanocrystals, comprising linearly stacked ZnSe, CdS, and Pt domains, which jointly promote photoinduced charge separation. These structures are used in aqueous solutions for the photocatalysis of water under solar radiation, resulting in the production of H2 gas. To enhance the photoinduced separation of charges, a nanorod morphology with a linear gradient originating from an intrinsic electric field is used5. The inter-domain energetics are then optimized to drive photogenerated electrons toward the Pt catalytic site while expelling the holes to the surface of ZnSe domains for sacrificial regeneration (via methanol). Here we show that the only efficient way to produce hydrogen is to use electron-donating ligands to passivate the surface states by tuning the energy level alignment at the semiconductor-ligand interface. Stable and efficient reduction of water is allowed by these ligands due to the fact that they fill vacancies in the valence band of the semiconductor domain, preventing energetic holes from degrading it. Specifically, we show that the energy of the hole is transferred to the ligand moiety, leaving the semiconductor domain functional. This enables us to return the entire nanocrystal-ligand system to a functional state, when the ligands are degraded, by simply adding fresh ligands to the system4. To promote a photovoltaic charge separation, we use a

  13. Integrated PEV Charging Solutions and Reduced Energy for Occupant Comfort (Brochure)

    2012-01-01

    Brochure on Vehicle Testing and Integration Facility, featuring the Vehicle Modification Facility, Vehicle Test Pad and ReCharge Integrated Demonstration System. Plug-in electric vehicles (PEVs) offer the opportunity to shift transportation energy demands from petroleum to electricity, but broad adoption will require integration with other systems. While automotive experts work to reduce the cost of PEVs, fossil fueled cars and trucks continue to burn hundreds of billions of gallons of petroleum each year - not only to get from point A to point B, but also to keep passengers comfortable with air conditioning and heat. At the National Renewable Energy Laboratory (NREL), three installations form a research laboratory known as the Vehicle Testing and Integration Facility (VTIF). At the VTIF, engineers are developing strategies to address two separate but equally crucial areas of research: meeting the demands of electric vehicle-grid integration and minimizing fuel consumption related to vehicle climate control. Part of NREL's Center for Transportation Technologies and Systems (CTTS), the VTIF is dedicated to renewable and energy efficient solutions. This facility showcases technology and systems designed to increase the viability of sustainably powered vehicles. NREL researchers instrument every class of on-road vehicle, conduct hardware and software validation for electric vehicle (EV) components and accessories, and develop analysis tools and technology for the Department of Energy, other government agencies and industry partners. Research conducted at the VTIF examines the interaction of building energy systems, utility grids, renewable energy sources and PEVs, integrating energy management solutions, and maximizing potential greenhouse gas (GHG) reduction, while smoothing the transition and reducing costs for EV owners. NREL's collaboration with automakers, charging station manufacturers, utilities and fleet operators to assess technologies using VTIF

  14. Identification and spectrometry of low-energy charged particles by means of ionization chamber with two grids

    The method of using an ionization chamber with two grids for identification and spectrometry of low-energy charged particles with the close energy, but different product of their mass and charge is described. The method enables to carry out multidimensional measurements of coincident pulses from the cathode and anode of ionization chamber. The selection circuit provides for relizble identification of different sorts of charged particles with close energy and essentially improves the raio of the effect and background at low energy resolution due to a radioactive target in the chamber. The method was used in investigation of reactions (n,p) on slow neutrons for radioactive targets 7Be, 36Cl, 88Y

  15. Charged-particle (pseudo)rapidity distributions in e+e-, pp, and AA collisions at high energies

    A unified formula which describes the (pseudo)rapidity distributions of charged particles produced in high energy collisions is presented. The calculated results are compared and found to be in agreement with the experimental data of e+e-, pp, and AA collisions at high energies

  16. Variational polaron self-interaction-corrected total-energy functional for charge excitations in insulators

    Sadigh, Babak; Erhart, Paul; Ã berg, Daniel

    2015-08-01

    We conduct a detailed investigation of the polaron self-interaction (pSI) error in standard approximations to the exchange-correlation (XC) functional within density-functional theory (DFT). The pSI leads to delocalization error in the polaron wave function and energy, as calculated from the Kohn-Sham (KS) potential in the native charge state of the polaron. This constitutes the origin of the systematic failure of DFT to describe the polaron formation in band insulators. It is shown that the delocalization error in these systems is, however, largely absent in the KS potential of the closed-shell neutral charge state. This leads to a modification of the DFT total-energy functional that corrects the pSI in the XC functional. The resulting pSIC-DFT method constitutes an accurate parameter-free ab initio methodology for calculating polaron properties in insulators at a computational cost that is orders of magnitude smaller than hybrid XC functionals. Unlike approaches that rely on parametrized localized potentials such as DFT+U , the pSIC-DFT method properly captures both site and bond-centered polaron configurations. This is demonstrated by studying formation and migration of self-trapped holes in alkali halides (bond-centered) as well as self-trapped electrons in an elpasolite compound (site-centered). The pSIC-DFT approach consistently reproduces the results obtained by hybrid XC functionals parametrized by DFT+G0W0 calculations. Finally, we generalize the pSIC approach to hybrid functionals, and show that in stark contrast to conventional hybrid calculations of polaron energies, the pSIC-hybrid method is insensitive to the parametrization of the hybrid XC functional. On this basis, we further rationalize the success of the pSIC-DFT approach.

  17. The dynamics of energy and charge transfer in lead sulfide quantum dot solids

    Lingley, Zachary [Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089 (United States); Lu, Siyuan [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089 (United States); Madhukar, Anupam, E-mail: madhukar@usc.edu [Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089 (United States); Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089 (United States)

    2014-02-28

    We report on a systematic time-resolved photoluminescence study of the competing energy and charge transfer rates in PbS QDs of differing sizes in the same QD solid as a function of both temperature and ligand-controlled different inter-QD average separations. This complements previous studies that typically varied only one parameter and reveals new aspects while also confirming some known features. For the smallest PbS QDs, the dominant decay process is nonradiative resonant energy transfer (NRET) to adjacent larger dots for all separations but at a rate that increases with decreasing temperature. For the largest QDs, NRET being forbidden, the decay is found to be exponential in the inter-QD separation consistent with carrier tunneling but, for each fixed tunneling distance, exhibiting a thermally activated tunneling carrier population with the activation energy dependent upon the ligand length controlling the inter-QD separation. A consistent understanding of this expanded and rich decay rate behavior of both large and small QDs, we show, can be obtained by accounting for the ligand length dependent (a) dielectric environment of the QD solid modeled using an effective medium description, (b) the energy cost of dissociating the exciton into electron and hole in neighboring QDs, and (c) the potential participation of midgap states. Implications of the findings for NRET based photovoltaics are discussed.

  18. Direct electron-pair production by high energy heavy charged particles

    Takahashi, Y.; Gregory, J. C.; Hayashi, T.; Dong, B. L.

    1989-01-01

    Direct electron pain production via virtual photons by moving charged particles is a unique electro-magnetic process having a substantial dependence on energy. Most electro-magnetic processes, including transition radiation, cease to be sensitive to the incident energy above 10 TeV/AMU. Thus, it is expected, that upon establishment of cross section and detection efficiency of this process, it may provide a new energy measuring technique above 10 TeV/AMU. Three accelerator exposures of emulsion chambers designed for measurements of direct electron-pains were performed. The objectives of the investigation were to provide the fundamental cross-section data in emulsion stacks to find the best-fit theoretical model, and to provide a calibration of measurements of direct electron-pairs in emulsion chamber configurations. This paper reports the design of the emulsion chambers, accelerator experiments, microscope measurements, and related considerations for future improvements of the measurements, and for possible applications to high energy cosmic ray experiments. Also discussed are the results from scanning 56m of emulsion tracks at 1200x magnification so that scanning efficiency is optimized. Measurements of the delta-ray range spectrum were also performed for much shorter track lengths, but with sufficiently large statistics in the number of measured delta-rays.

  19. Parton Energy Loss in Heavy-Ion Collisions via Direct-Photon and Charged-Particle Azimuthal Correlations

    Abelev, B. I.; Benedosso, F.; Braidot, E.; Mischke, A.; Peitzmann, T.(Institute for Subatomic Physics of Utrecht University, Utrecht, Netherlands); Russcher, M. J.

    2010-01-01

    Charged-particle spectra associated with direct photon ($\\gamma_{dir} $) and $\\pi^0$ are measured in $p$+$p$ and Au+Au collisions at center-of-mass energy $\\sqrt{s_{_{NN}}}=200$ GeV with the STAR detector at RHIC. A hower-shape analysis is used to partially discriminate between $\\gamma_{dir}$ and $\\pi^0$. Assuming no associated charged particles in the $\\gamma_{dir}$ direction (near side) and small contribution from fragmentation photons ($\\gamma_{frag}$), the associated charged-particle yiel...

  20. Energy loss of high velocity 6Li2+ ions in carbon foils in charge state non-equilibrium region

    Mean energy losses of high velocity H-like Li ions in thin carbon foils were measured in the charge state non-equilibrium region. Owing to the screening effect of the bound electron, the fixed-charge stopping power for 6Li2+ was smaller than that for 6Li3+. The projectile atomic number dependence of the fixed-charge stopping powers for H-like ions is discussed including our previous data of He, C and O ions with the same velocity. The present result is also compared with the theoretical prediction. (orig.)

  1. The Ionic Charge State Composition at High Energies in Large Solar Energetic Particle Events in Solar Cycle 23

    Leske, R. A.; Mewaldt, R. A.; Cummings, A. C.; Stone, E. C.; von Rosenvinge, T. T.

    2001-01-01

    The ionic charge states of solar energetic particles (SEPs) depend upon the temperature of the source material and on the environment encountered during acceleration and transport during which electron stripping may occur. Measurements of SEP charge states at relatively high energies (≳15 MeV/nucleon) are possible with the Mass Spectrometer Telescope (MAST) on the Solar, Anomalous, and Magnetospheric Particle Explorer satellite by using the Earth's magnetic field as a particle rigidity filter...

  2. Roles of Energy/Charge Cascades and Intermixed Layers at Donor/Acceptor Interfaces in Organic Solar Cells

    Nakano, Kyohei; Suzuki, Kaori; Chen, Yujiao; Tajima, Keisuke

    2016-01-01

    The secret to the success of mixed bulk heterojunctions (BHJs) in yielding highly efficient organic solar cells (OSCs) could reside in the molecular structures at their donor/acceptor (D/A) interfaces. In this study, we aimed to determine the effects of energy and charge cascade structures at the interfaces by using well-defined planar heterojunctions (PHJs) as a model system. The results showed that (1) the charge cascade structure enhanced VOC because it shuts down the recombination pathway through charge transfer (CT) state with a low energy, (2) the charge cascade layer having a wider energy gap than the bulk material decreased JSC because the diffusion of the excitons from the bulk to D/A interface was blocked; the energy of the cascade layers must be appropriately arranged for both the charges and the excitons, and (3) molecular intermixing in the cascade layer opened the recombination path through the low-energy CT state and decreased VOC. Based on these findings, we propose improved structures for D/A interfaces in BHJs. PMID:27404948

  3. A comparison of experimental thermal stratification parameters for an oil/pebble-bed thermal energy storage (TES) system during charging

    Highlights: → Six experimental thermal stratification parameters are evaluated in a TES system. → Stratification number and temperature difference evaluate stratification adequately. → Exergy efficiency and Reynolds number evaluate stratification qualitatively. → Richardson number and energy efficiency not clearly related with stratification. -- Abstract: Six different experimental thermal stratification evaluation parameters during charging for an oil/pebble-bed TES system are presented. The six parameters are the temperature distribution along the height of the storage tank at different time intervals, the charging energy efficiency, the charging exergy efficiency, the stratification number, the Reynolds number and the Richardson number. These parameters are evaluated under six different experimental charging conditions. Temperature distribution along the height of the storage tank at different time intervals and the stratification number are parameters found to describe thermal stratification quantitatively adequately. On the other-hand, the charging exergy efficiency and the Reynolds number give important information about describing thermal stratification qualitatively and should be used with care. The charging energy efficiency and the Richardson number have no clear relationship with thermal stratification.

  4. Concentration dependence of the transport energy level for charge carriers in organic semiconductors

    Oelerich, J. O.; Huemmer, D.; Weseloh, M.; Baranovskii, S. D.

    2010-10-01

    The concept of the transport energy (TE) has proven to be one of the most powerful theoretical approaches to describe charge transport in organic semiconductors. In the recent paper L. Li, G. Meller, and H. Kosina [Appl. Phys. Lett. 92, 013307 (2008)] have studied the effect of the partially filled localized states on the position of the TE level. We show that the position of the TE is essentially different to the one suggested by L. Li, G. Meller, and H. Kosina [Appl. Phys. Lett. 92, 013307 (2008)] We further modify the standard TE approach taking into account the percolation nature of the transport path. Our calculations show that the TE becomes dependent on the concentration of charge carriers n at much higher n values than those, at which the carrier mobility already strongly depends on n. Hence the calculations of the concentration-dependent carrier mobility cannot be performed within the approach, in which only the concentration dependence of the TE is taken into account.

  5. Cellular and molecular analysis of mutagenesis induced by charged particles of defined linear energy transfer

    Zhu, L. X.; Waldren, C. A.; Vannias, D.; Hei, T. K.; Chatterjee, A. (Principal Investigator)

    1996-01-01

    Mutation induction by charged particles of defined linear energy transfer (LET) and gamma rays was scored using human-hamster hybrid AL cells. The LET values for charged particles accelerated at the Radiological Research Accelerator Facility ranged from 10 keV/microm protons to 150 keV/microm 4He ions. The induced mutant fractions at both the S1 and HGPRT loci were dependent on the dose and LET. In addition, for each dose examined, the mutant yield at the S1 locus was 30-60 fold higher than at the corresponding HGPRT locus. To determine whether the mutation spectrum was comparably dependent on dose and LET, independent S1- and HGPRT- mutants induced by 150 keV/microm 4He ions and gamma rays were isolated, and their DNA was analyzed by both Southern blotting and multiplex PCR methods. While the majority of radiation-induced mutants showed deletions of varying sizes, the relative percentage of large deletions was found to be related to both the dose and LET of the radiation examined. Using a mutation system that can detect multilocus changes, results of the present study show that radiation-induced chromosomal loss can be in the millions of base pairs.

  6. Charged current antineutrino reactions from 12C at MiniBooNE energies

    A study of charged current induced antineutrino interactions from nuclei has been done for the intermediate energy antineutrinos and applied to 12C, relevant for ongoing experiment by MiniBooNE collaboration. The calculations have been done for the quasielastic and inelastic lepton production as well as for the incoherent and the coherent pion production processes. The calculations are done in local density approximation. In the case of the quasielastic reaction the effects of Pauli blocking, Fermi motion effects, renormalization of weak transition strengths in nuclear medium and the Coulomb distortion of the outgoing lepton have been taken into account. For the inelastic processes the calculations have been done in the Δ dominance model and take into account the effect of Pauli blocking, Fermi motion of the nucleon, and renormalization of Δ properties in a nuclear medium. The effect of final state interactions of pions is also taken into account. The numerical results for the total cross sections for the charged current quasielastic scattering and incoherent pion production processes are compared with earlier experimental results available in freon and freon-propane. It is found that nuclear medium effects give strong reduction in the cross sections leading to satisfactory agreement with the available data

  7. Correlation versus mean-field contributions to excitons, multiexcitons, and charging energies in semiconductor quantum dots

    Single-dot spectroscopy is now able to resolve the energies of excitons, multiexcitons, and charging of semiconductor quantum dots with ∼<1 meV resolution. We discuss the physical content of these energies and show how they can be calculated via quantum Monte Carlo (QMC) and configuration interaction (CI) methods. The spectroscopic energies have three pieces: (i) a ''perturbative part'' reflecting carrier-carrier direct and exchange Coulomb energies obtained from fixed single-particle orbitals, (ii) a ''self-consistency correction'' when the single particle orbitals are allowed to adjust to the presence of carrier-carrier interaction, and (iii) a ''correlation correction.'' We first apply the QMC and CI methods to a model single-particle Hamiltonian: a spherical dot with a finite barrier and single-band effective mass. This allows us to test the convergence of the CI and to establish the relative importance of the three terms (i)--(iii) above. Next, we apply the CI method to a realistic single-particle Hamiltonian for a CdSe dot, including via a pseudopotential description the atomistic features, multiband coupling, spin-orbit effects, and surface passivation. We include all bound states (up to 40000 Slater determinants) in the CI expansion. Our study shows that (1) typical exciton transition energies, which are ∼1 eV, can be calculated to better than 95% by perturbation theory, with only a ∼2 meV correlation correction; (2) typical electron addition energies are ∼40 meV, of which correlation contributes very little (∼1 meV); (3) typical biexciton binding energies are positive and ∼10 meV and almost entirely due to correlation energy, and exciton addition energies are ∼30 meV with nearly all contribution due to correlation; (4) while QMC is currently limited to a single-band effective-mass Hamiltonian, CI may be used with much more realistic models, which capture the correct symmetries and electronic structure of the dots, leading to qualitatively

  8. Six git genes encode a glucose-induced adenylate cyclase activation pathway in the fission yeast Schizosaccharomyces pombe

    Susan M. Byrne; Hoffman, Charles S.

    1993-01-01

    An important eukaryotic signal transduction pathway involves the regulation of the effector enzyme adenylate cyclase, which produces the second messenger, cAMP. Previous genetic analyses demonstrated that glucose repression of transcription of the Schizosaccharomyces pombe fbp1 gene requires the function of adenylate cyclase, encoded by the git2 gene. As mutations in git2 and in six additional git genes are suppressed by exogenous cAMP, these ‘upstream’ git genes were proposed to act to produ...

  9. The Crystal Structure of the Adenylation Enzyme VinN Reveals a Unique β-Amino Acid Recognition Mechanism*

    Miyanaga, Akimasa; Cieślak, Jolanta; Shinohara, Yuji; Kudo, Fumitaka; Eguchi, Tadashi

    2014-01-01

    Adenylation enzymes play important roles in the biosynthesis and degradation of primary and secondary metabolites. Mechanistic insights into the recognition of α-amino acid substrates have been obtained for α-amino acid adenylation enzymes. The Asp residue is invariant and is essential for the stabilization of the α-amino group of the substrate. In contrast, the β-amino acid recognition mechanism of adenylation enzymes is still unclear despite the importance of β-amino acid activation for the biosynthesis of various natural products. Herein, we report the crystal structure of the stand-alone adenylation enzyme VinN, which specifically activates (2S,3S)-3-methylaspartate (3-MeAsp) in vicenistatin biosynthesis. VinN has an overall structure similar to that of other adenylation enzymes. The structure of the complex with 3-MeAsp revealed that a conserved Asp230 residue is used in the recognition of the β-amino group of 3-MeAsp similar to α-amino acid adenylation enzymes. A mutational analysis and structural comparison with α-amino acid adenylation enzymes showed that the substrate-binding pocket of VinN has a unique architecture to accommodate 3-MeAsp as a β-amino acid substrate. Thus, the VinN structure allows the first visualization of the interaction of an adenylation enzyme with a β-amino acid and provides new mechanistic insights into the selective recognition of β-amino acids in this family of enzymes. PMID:25246523

  10. The crystal structure of the adenylation enzyme VinN reveals a unique β-amino acid recognition mechanism.

    Miyanaga, Akimasa; Cieślak, Jolanta; Shinohara, Yuji; Kudo, Fumitaka; Eguchi, Tadashi

    2014-11-01

    Adenylation enzymes play important roles in the biosynthesis and degradation of primary and secondary metabolites. Mechanistic insights into the recognition of α-amino acid substrates have been obtained for α-amino acid adenylation enzymes. The Asp residue is invariant and is essential for the stabilization of the α-amino group of the substrate. In contrast, the β-amino acid recognition mechanism of adenylation enzymes is still unclear despite the importance of β-amino acid activation for the biosynthesis of various natural products. Herein, we report the crystal structure of the stand-alone adenylation enzyme VinN, which specifically activates (2S,3S)-3-methylaspartate (3-MeAsp) in vicenistatin biosynthesis. VinN has an overall structure similar to that of other adenylation enzymes. The structure of the complex with 3-MeAsp revealed that a conserved Asp(230) residue is used in the recognition of the β-amino group of 3-MeAsp similar to α-amino acid adenylation enzymes. A mutational analysis and structural comparison with α-amino acid adenylation enzymes showed that the substrate-binding pocket of VinN has a unique architecture to accommodate 3-MeAsp as a β-amino acid substrate. Thus, the VinN structure allows the first visualization of the interaction of an adenylation enzyme with a β-amino acid and provides new mechanistic insights into the selective recognition of β-amino acids in this family of enzymes. PMID:25246523

  11. Identification of residues essential for catalysis and binding of calmodulin in Bordetella pertussis adenylate cyclase by site-directed mutagenesis.

    Glaser, P; Elmaoglou-Lazaridou, A; Krin, E.; Ladant, D.; Bârzu, O; Danchin, A

    1989-01-01

    In order to identify molecular features of the calmodulin (CaM) activated adenylate cyclase of Bordetella pertussis, a truncated cya gene was fused after the 459th codon in frame with the alpha-lacZ' gene fragment and expressed in Escherichia coli. The recombinant, 604 residue long protein was purified to homogeneity by ion-exchange and affinity chromatography. The kinetic parameters of the recombinant protein are very similar to that of adenylate cyclase purified from B.pertussis culture sup...

  12. Space-charge neutralization experiment with a low-energy proton beam

    The mechanism of space-charge neutralization of a low-energy proton beam is investigated both experimentally and theoretically. In the experiment, the transverse profile of a 500 keV proton beam delivered by a duoplasmatron source is accurately measured at the end of a 3 m long drift space. Profile measurements are performed by an imaging technique using a scintillating screen and an intensified CCD camera. Measurement results done with different beam intensities (between 0.5 and 15 mA) and various residual-gas pressures are described. They show that, at high beam current an increase of the gas pressure results in a reduction of the beam spot, which indicates an increase of the value of the neutralization coefficient. On the other hand, the behavior is the opposite at low beam current: the beam size increases with the gas pressure. An interpretation of these experimental results is proposed. (author)

  13. The Binding Energy, Spin-Excitation Gap, and Charged Gap in the Boson-Fermion Model

    YANG Kai-Hua; TIAN Guang-Shan; HAN Ru-Qi

    2003-01-01

    In this paper, by applying a simplified version of Lieb 's spin-refleetion-positivity method, which was recentlydeveloped by one of us [G.S. Tian and J.G. Wang, J. Phys. A: Math. Gen. 35 (2002) 941], we investigate some generalproperties of the boson-fermion Hamiltonian, which has been widely used as a phenomenological model to describe thereal-space pairing of electrons. On a mathematically rigorous basis, we prove that for either negative or positive couplingV, which represents the spontaneous decay and recombination process between boson and fermion in the model, thepairing energy of electrons is nonzero. Furthermore, we also show that the spin-excitation gap of the boson-fermionHamiltonian is always larger than its charged gap, as predicted by the pre-paired electron theory.

  14. The Binding Energy, Spin-Excitation Gap, and Charged Gap in the Boson-Fermion Model

    YANGKai-Hua; Guang-Shan; HANRu-Qi

    2003-01-01

    In this paper, by applying a simplified version of Lieb's spin-reflection-positivity method, which was recently developed by one of us [G.S. Tian and J.G. Wang, J. Phys. A: Math. Gen. 35 (2002) 941], we investigate some general properties of the boeon-fermion Hamiltonlan, which has been widely used as a phenomenological model to describe the real-space pairing of electrons. On a mathematically rigorous basis, we prove that for either negative or positive couping V, which represents the spontaneous decay and recombination process between boson and fermion in the model, the pairing energy of electrons is nonzero. Furthermore, we also show that the spin-excitation gap of the boson-fermion Hamiltonian is always larger than its charged gap, as predicted by the pre-palred electron theory.

  15. Charge neutralized low energy beam transport at Brookhaven 200 MeV linac

    The H− magnetron source provides about 100 mA H− beam to be match into the radio-frequency quadrupole accelerator. As H− beam traverses through low energy transport, it ionizes the residual gas and electrons are repelled and positive ions are trapped in the beam, due to negative potential of the beam, providing charge neutralization for the H− beam. The neutralization time for the critical density depends upon the background gas and its pressure. Critical density for xenon gas at 35 keV is about 43 times smaller than that of hydrogen and stripping cross section is only 5 times than that of hydrogen gas. We are using xenon gas to reduce neutralization time and to improve transmission through the 200 MeV linac. We are also using pulse nitrogen gas to improve transmission and stability of polarized H− beam from optically pumped polarized ion source

  16. Integrated bistable generator for wideband energy harvesting with optimized synchronous electric charge extraction circuit

    Bistable generators have been proposed as potential solutions to the challenge of variable vibration frequencies. In the authors' previous works, a specific BSM (Buckled-Spring-Mass) harvester architecture has been suggested. It presents some properties of interests: simplicity, compactness and wide bandwidth. Using a normalized model of the BSM generator for design and optimization at different scales, this paper presents a new integrated BSM bistable generator design with the OSECE (Optimized Synchronous Electric Charge Extraction) technique which is used for broadband energy harvesting. The experimental results obtained from an initial prototype device show that the BSM generator with the OSECE circuit exhibits better performance for low coupling cases or reverse sweep excitations. This is also confirmed by simulations for the proposed integrated generator. Good applications prospective is expected for the bistable generator with the nonlinear OSECE circuit

  17. A low energy ion beamline for highly charged ions at SpecTrap

    One of the precision experiments of the HITRAP facility at GSI Darmstadt is SpecTrap, which aims to trap heavy Highly Charged Ions (HCI) in a Penning trap and cool them to cryogenic temperatures. Using laser spectroscopy it is possible to measure their hyperfine structure with an envisaged relative accuracy of the order of 10-7 which will serve as a test of strong-field quantum electrodynamics. This poster presents the current status of the SpecTrap experiment and give an overview of the associated beamline from the Electron Beam Ion Source (EBIS) to the Penning trap. The EBIS can produce HCI up to Xe44+ and the beamline is able to transport these ions with small kinetic energy with a few keV to SpecTrap or other experimental setups. Additionally the methods and first experimental results for detecting, cooling and manipulating the ions inside the trap are shown.

  18. Charge neutralized low energy beam transport at Brookhaven 200 MeV linac.

    Raparia, D; Alessi, J; Atoian, G; Zelenski, A

    2016-02-01

    The H(-) magnetron source provides about 100 mA H(-) beam to be match into the radio-frequency quadrupole accelerator. As H(-) beam traverses through low energy transport, it ionizes the residual gas and electrons are repelled and positive ions are trapped in the beam, due to negative potential of the beam, providing charge neutralization for the H(-) beam. The neutralization time for the critical density depends upon the background gas and its pressure. Critical density for xenon gas at 35 keV is about 43 times smaller than that of hydrogen and stripping cross section is only 5 times than that of hydrogen gas. We are using xenon gas to reduce neutralization time and to improve transmission through the 200 MeV linac. We are also using pulse nitrogen gas to improve transmission and stability of polarized H(-) beam from optically pumped polarized ion source. PMID:26932107

  19. Supercell convergence of charge-transfer energies in pentacene molecular crystals from constrained DFT

    Turban, David H. P.; Teobaldi, Gilberto; O'Regan, David D.; Hine, Nicholas D. M.

    2016-04-01

    Singlet fission (SF) is a multiexciton generation process that could be harnessed to improve the efficiency of photovoltaic devices. Experimentally, systems derived from the pentacene molecule have been shown to exhibit ultrafast SF with high yields. Charge-transfer (CT) configurations are likely to play an important role as intermediates in the SF process in these systems. In molecular crystals, electrostatic screening effects and band formation can be significant in lowering the energy of CT states, enhancing their potential to effectively participate in SF. In order to simulate these, it desirable to adopt a computational approach which is acceptably accurate, relatively inexpensive, and which scales well to larger systems, thus enabling the study of screening effects. We propose an electrostatically corrected constrained density functional theory (cDFT) approach as a low-cost solution to the calculation of CT energies in molecular crystals such as pentacene. Here we consider an implementation in the context of the onetep linear-scaling DFT code, but our electrostatic correction method is in principle applicable in combination with any constrained DFT implementation, also outside the linear-scaling framework. Our newly developed method allows us to estimate CT energies in the infinite crystal limit, and with these to validate the accuracy of the cluster approximation.

  20. An energy harvester using self-powered feed forward converter charging approach

    The paper proposes a stand-alone energy harvester system that considers economical, environmental, and technological implications. The applications of this paper are maintenance free, low cost and environmentally friendly commercial devices. The stand-alone system contains a self starting/self powering circuitry which allows the system power to be turned off while not in use. This proposed system requires neither batteries nor a power supply unit; it constitutes a true stand-alone, low maintenance and pollution free system. Additionally, it proposes a feed forward charging scheme to eliminate the needs of using voltage feedback, current feedback, or both, and hence reduces electronic complexity and cost of the charger. A detailed analysis of the feed forward charger, and the self-starting/self power circuitry was carried out to obtain the relationship between the system parameters and the outputs of the system. This paper also presents simulation results and experimental data to reveal performance of the charger and the self-starting/self powering circuitry. - Highlights: ► We frame an energy harvester that requires neither batteries nor a power supply unit. ► The harvester can avoid impacting the lifetime quality of energy storage elements. ► We show a thorough operation analysis for both ideal and non-ideal cases. ► The harvester possesses simplicity, low cost, and commercialization potential. ► Design concept integrates technical, economic and environmental concerns

  1. 36-MeV-triton-induced charge exchange: Mass measurements and energy levels of neutron-rich nuclei and the charge exchange reaction mechanism

    Energy spectra and differential cross sections have been obtained for the charge exchange reaction (3H,3He) on targets of /sup 30,28/Si and /sup 26/Mg at an incident energy of 36 MeV. Previously unobserved energy levels of /sup 30/Al and /sup 26/Na are reported and compared to shell model predictions. Microscopic form factors based on the M3Y effective nucleon-nucleon interaction are used in distorted-wave Born approximation codes to fit the data. The sensitivity of the model to input parameters is discussed and some spin assignments made. Coupled channels calculations are performed to fit the two-step contributions to the data via sequential one-nucleon transfers

  2. The charge-energy-mass spectrometer for 0.3-300 keV/e ions on the AMPTE CCE

    Gloeckler, G.; Ipavich, F. M.; Hamilton, D. C.; Lundgren, R. A.; Studemann, W.; Wilken, B.; Kremser, G.; Hovestadt, D.; Gliem, F.; Rieck, W.

    1985-01-01

    The charge-energy-mass (CHEM) spectrometer on the Charge Composition Explorer (CCE) has the function to measure the energy spectra, pitch-angle distributions, and ionization states of ions in the earth's magnetosphere and magnetosheath in the energy range from 0.3 to 300 keV/charge with a time resolution of less than 1 min. The obtained data will provide essential information on outstanding problems related to ion sources and dynamical processes of space plasmas and of suprathermal ions. A description of the CHEM experiment is given, taking into account the principle of operation, the sensor, the electronics, instrument characteristics, specifications, and requirements. Questions of postlaunch performance are also discussed.

  3. Isotopic dependence of the nuclear charge radii and binding energies in the relativistic Hartree-Fock formalism

    Niembro, R., E-mail: niembror@unican.es; Marcos, S.; Lopez-Quelle, M. [Universidad de Cantabria (Spain); Savushkin, L. N. [St. Petersburg University for Telecommunications (Russian Federation)

    2012-03-15

    Relativistic nonlinear models based on the Hartree and Hartree-Fock approximations, including the {sigma}, {omega}, {pi}, and {rho} mesons, are worked out to explore the behavior of the nuclear charge radii and the binding energies of several isotopic chains. We find a correlation between the magnitude of the anomalous kink effect (KE) in the Pb isotopic family and the compressibility modulus (K) of nuclear matter. The KE appears to be sensitive, in particular, to the mechanisms which control the K value. The influence of the symmetry energy on the Ca isotopic chain is also studied. The behavior of the charge radii of single-particle states for some special cases and its repercussion on the nuclear charge radius is analyzed. The effect of pairing correlations on the models improves considerably the quality of the results in both binding energy and KE.

  4. Electric Vehicles Integration in the Electric Power System with Intermittent Energy Sources - The Charge/Discharge infrastructure

    Marra, Francesco

    The replacement of conventional fuelled vehicles with electric vehicles (EVs) is going to increase in the coming years, following the trend seen for renewable energy sources (RES), as photovoltaic (PV) and wind power. In this scenario, the electric power systems in Europe are going to accommodate...... increased levels of non-dispatchable and fluctuating energy sources, as well as additional power demand due to EV charging. If the charging of EVs can be intelligently managed, several advantages can be offered to the power system. How useful coordinated EV charging can be, in combination with RES...... and the power levels needed. Furthermore, during EV coordination, a number of nonlinearities and battery ageing issues should be taken into account, to ensure a correct EV coordination and to preserve the EV battery lifetime. The third part of this research exploits the use of EV load coordination as an energy...

  5. Lateral charged particle distribution of extensive air showers - source of information about energy and nature of the primary cosmic particles

    The CORSIKA simulated showers for H, C and Fe cosmic primaries in 8 energy intervals from 1016 eV to 1018 eV, taking into account the response of KASCADE-Grande detectors, have been used to reconstruct the charged particle density for KASCADE-Grande observations, based on the Linsley lateral distribution function (LDF). Extensive studies have been done to investigate features for energy estimation and mass discrimination of cosmic primaries around 1017 eV. It has been found that the charged particle density distribution of EAS exhibits interesting information for both aspects: at larger distances from shower core, around 500 m - 600 m the charge particle density could be used as energy identifier, and at shorter distances from shower core, around, 100 m - 200 m, it signals the mass of the EAS primary. (author)

  6. The knee in the cosmic ray energy spectrum from the simultaneous EAS charged particles and muon density spectra

    Bijay, Biplab; Bhadra, Arunava

    2015-01-01

    In this work we examine with the help of Monte Carlo simulation whether a consistent primary energy spectrum of cosmic rays emerges from both the experimentally observed total charged particles and muon size spectra of cosmic ray extensive air showers considering primary composition may or may not change beyond the knee of the energy spectrum. It is found that EAS-TOP observations consistently infer a knee in the primary energy spectrum provided the primary is pure unchanging iron whereas no consistent primary spectrum emerges from simultaneous use of the KASCADE observed total charged particle and muon spectra. However, it is also found that when primary composition changes across the knee the estimation of spectral index of total charged particle spectrum is quite tricky, depends on the choice of selection of points near the knee in the size spectrum.

  7. Invited Review Article: Contemporary instrumentation and application of charge exchange neutral particle diagnostics in magnetic fusion energy experiments

    An overview of the developments postcirca 1980s in the instrumentation and application of charge exchange neutral particle diagnostics on magnetic fusion energy experiments is presented. First, spectrometers that employ only electric fields and hence provide ion energy resolution but not mass resolution are discussed. Next, spectrometers that use various geometrical combinations of both electric and magnetic fields to provide both energy and mass resolutions are reviewed. Finally, neutral particle diagnostics based on utilization of time-of-flight techniques are presented

  8. Action of radioprotectors - venoms of Central Asian snakes and radiation on the adenylate cyclase system

    Action of venoms of Central Asian snakes (Maja oxiana and Vipera labertina turahica) as radioprotectors on 3'-5'-AMP content and activity of adenylate cyclase and phosphodiesterase in homogenates of liver and spleen of rats 1 and 24 hours after irradiation (800 R) has been studied. c-AMP content and adenylate cyclase activity have been shown to decrease drastically in the organs under study after the action of ionizing radiation. Preventive administration of venoms of cobra (150 μ g/kg) and (700 μ g/kg) one hour before irradiation restores the activity of the enzyme and c - AMP content of the spleen up to 53% and of the liver, to 30%. Phosphodiesterase activity increased markedly after irradiation being practically unaffected by the protector

  9. Characterization of Charge-Carrier Transport in Semicrystalline Polymers: Electronic Couplings, Site Energies, and Charge-Carrier Dynamics in Poly(bithiophene- alt -thienothiophene) [PBTTT

    Poelking, Carl

    2013-01-31

    We establish a link between the microscopic ordering and the charge-transport parameters for a highly crystalline polymeric organic semiconductor, poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT). We find that the nematic and dynamic order parameters of the conjugated backbones, as well as their separation, evolve linearly with temperature, while the side-chain dynamic order parameter and backbone paracrystallinity change abruptly upon the (also experimentally observed) melting of the side chains around 400 K. The distribution of site energies follows the behavior of the backbone paracrystallinity and can be treated as static on the time scale of a single-charge transfer reaction. On the contrary, the electronic couplings between adjacent backbones are insensitive to side-chain melting and vary on a much faster time scale. The hole mobility, calculated after time-averaging of the electronic couplings, reproduces well the value measured in a short-channel thin-film transistor. The results underline that to secure efficient charge transport in lamellar arrangements of conjugated polymers: (i) the electronic couplings should present high average values and fast dynamics, and (ii) the energetic disorder (paracrystallinity) should be small. © 2013 American Chemical Society.

  10. Absorbing Charged Rotating Metric in de Sitter Space in Advanced Time Coordinates and the Related Energy-Momentum Tensor

    XU Dian-Yah

    2000-01-01

    Absorbing charged rotating (ACR) metric in de Sitter space and related energy-momentum tensor are derived.The ACR metric is very simple in advanced time coordinates. The ACR metric involves 8 independent parameters which are divided into two classes: (1) the mass M, charge Q, angular momentum per unit mass a, and cosmological constant A; (2) M/ v, 2M/ v2, Q/ v, and 2Q/ v2. The non-stationary part of the energy-momentum tensor is positive definite everywhere.

  11. Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy Storage in DC Microgrids

    Li, Chendan; Dragicevic, Tomislav; Aldana, Nelson Leonardo Diaz; Vasquez, Juan Carlos; Guerrero, Josep M.

    2014-01-01

    Due to higher power quality, lower conversion loss, and more DC loads, there has been an increasing awareness on DC microgrid. Previous emphasis has been on equal power sharing among different units in the DC microgrid, whileoverlooking the coordination of the energy storage units to maintain the State-of-Charge balance. In this paper, a new droop method based on voltage scheduling for State-of-Charge balance is proposed to keep the SoC balance for the energy storage units. The proposed metho...

  12. Quantification of potassium levels in cells treated with Bordetella adenylate cyclase toxin

    Wald, Tomáš; Petry-Podgorska, Inga; Fišer, Radovan; Matoušek, Tomáš; Dědina, Jiří; Osička, Radim; Šebo, Peter; Mašín, Jiří

    2014-01-01

    Roč. 450, APR 2014 (2014), s. 57-62. ISSN 0003-2697 R&D Projects: GA ČR(CZ) GAP302/11/0580; GA ČR GA13-14547S; GA ČR GAP302/12/0460 Institutional support: RVO:61388971 ; RVO:68081715 Keywords : Potassium * Adenylate cyclase toxin * RTX Subject RIV: CE - Biochemistry Impact factor: 2.219, year: 2014

  13. Comprehensive behavioral analysis of pituitary adenylate cyclase-activating polypeptide (PACAP) knockout mice

    Koichi Tanda; Norihito Shintani; Akemichi Baba; Hitoshi Hashimoto; Tsuyoshi Miyakawa

    2012-01-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide acting as a neurotransmitter, neuromodulator, or neurotrophic factor. PACAP is widely expressed throughout the brain and exerts its functions through the PACAP-specific receptor (PAC1). Recent studies reveal that genetic variants of the PACAP and PAC1 genes are associated with mental disorders, and several behavioral abnormalities of PACAP knockout (KO) mice are reported. However, an insufficient number of backcrosse...

  14. Evidence for positive selection acting on microcystin synthetase adenylation domains in three cyanobacterial genera

    Rouhiainen Leo

    2008-09-01

    Full Text Available Abstract Background Cyanobacteria produce a wealth of secondary metabolites, including the group of small cyclic heptapeptide hepatotoxins that constitutes the microcystin family. The enzyme complex that directs the biosynthesis of microcystin is encoded in a single large gene cluster (mcy. mcy genes have a widespread distribution among cyanobacteria and are likely to have an ancient origin. The notable diversity within some of the Mcy modules is generated through various recombination events including horizontal gene transfer. Results A comparative analysis of the adenylation domains from the first module of McyB (McyB1 and McyC in the microcystin synthetase complex was performed on a large number of microcystin-producing strains from the Anabaena, Microcystis and Planktothrix genera. We found no decisive evidence for recombination between strains from different genera. However, we detected frequent recombination events in the mcyB and mcyC genes between strains within the same genus. Frequent interdomain recombination events were also observed between mcyB and mcyC sequences in Anabaena and Microcystis. Recombination and mutation rate ratios suggest that the diversification of mcyB and mcyC genes is driven by recombination events as well as point mutations in all three genera. Sequence analysis suggests that generally the adenylation domains of the first domain of McyB and McyC are under purifying selection. However, we found clear evidence for positive selection acting on a number of amino acid residues within these adenylation domains. These include residues important for active site selectivity of the adenylation domain, strongly suggesting selection for novel microcystin variants. Conclusion We provide the first clear evidence for positive selection acting on amino acid residues involved directly in the recognition and activation of amino acids incorporated into microcystin, indicating that the microcystin complement of a given strain may

  15. Interaction of Bordetella adenylate cyclase toxin with complement receptor 3 involves multivalent glycan binding

    Hasan, Shakir; Osičková, Adriana; Bumba, Ladislav; Novák, Petr; Šebo, Peter; Osička, Radim

    2015-01-01

    Roč. 589, č. 3 (2015), s. 374-379. ISSN 0014-5793 R&D Projects: GA ČR(CZ) GAP302/11/0580; GA ČR(CZ) GA15-09157S; GA ČR(CZ) GA15-11851S Institutional support: RVO:61388971 Keywords : Adenylate cyclase toxin * CD11b/CD18 * Complement receptor type 3 Subject RIV: CE - Biochemistry Impact factor: 3.169, year: 2014

  16. Bordetella adenylate cyclase toxin is a unique ligand of the integrin complement receptor 3

    Osička, Radim; Osičková, Adriana; Hasan, Shakir; Bumba, Ladislav; Černý, Jiří; Šebo, Peter

    2015-01-01

    Roč. 4, DEC 9 (2015). ISSN 2050-084X R&D Projects: GA ČR(CZ) GAP302/11/0580; GA ČR(CZ) GA15-11851S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 ; RVO:86652036 Keywords : E. coli * adenylate cyclase toxin * biochemistry Subject RIV: CE - Biochemistry Impact factor: 9.322, year: 2014

  17. Bordetella pertussis adenylate cyclase toxin translocation across a tethered lipid bilayer

    Veneziano, Rémi; Rossi, Claire; Chenal, Alexandre; Devoisselle, Jean-Marie; Ladant, Daniel; Chopineau, Joel

    2013-01-01

    Many bacterial toxins can cross biological membranes to reach the cytosol of mammalian cells, although how they pass through a lipid bilayer remains largely unknown. Bordetella pertussis adenylate cyclase (CyaA) toxin delivers its catalytic domain directly across the cell membrane. To characterize this unique translocation process, we designed an in vitro assay based on a tethered lipid bilayer assembled over a biosensor surface derivatized with calmodulin, a natural activator of the toxin. C...

  18. Final state effects on charge asymmetry of pion elliptic flow in high-energy heavy-ion collisions

    Ma, Guo-Liang

    2014-01-01

    Within a multi-phase transport (AMPT) model with string melting mechanism and an imported electric charge quadrupole distribution in the initial partonic coordinate space, the elliptic flow asymmetry between positive and negative pions is investigated. The slope parameter $r$ of the linear dependence of $\\Delta v_{2}=v_{2}(\\pi^{-})-v_{2}(\\pi^{+})$ on $A_{ch}=(N^{+}-N^{-})/(N^{+}+N^{-})$ is yielded by the conversion from an initial electric charge quadrupole distribution to a charge-dependent elliptic flow via a strong parton cascade process. The slope parameter $r$ is increased by the hadronization of coalescence, and then decreased by final resonance decays. Because the slope parameter $r$ is very sensitive to both initial electric charge quadrupole percentage and centrality, a helpful constraint of the effect from chiral magnetic wave is extracted out in Au+Au collisions at the top RHIC energy.

  19. XLF-Cernunnos promotes DNA ligase IV-XRCC4 re-adenylation following ligation.

    Riballo, Enriqueta; Woodbine, Lisa; Stiff, Thomas; Walker, Sarah A; Goodarzi, Aaron A; Jeggo, Penny A

    2009-02-01

    XLF-Cernunnos (XLF) is a component of the DNA ligase IV-XRCC4 (LX) complex, which functions during DNA non-homologous end joining (NHEJ). Here, we use biochemical and cellular approaches to probe the impact of XLF on LX activities. We show that XLF stimulates adenylation of LX complexes de-adenylated by pyrophosphate or following LX decharging during ligation. XLF enhances LX ligation activity in an ATP-independent and dependent manner. ATP-independent stimulation can be attributed to enhanced end-bridging. Whilst ATP alone fails to stimulate LX ligation activity, addition of XLF and ATP promotes ligation in a manner consistent with XLF-stimulated readenylation linked to ligation. We show that XLF is a weakly bound partner of the tightly associated LX complex and, unlike XRCC4, is dispensable for LX stability. 2BN cells, which have little, if any, residual XLF activity, show a 3-fold decreased ability to repair DNA double strand breaks covering a range of complexity. These findings strongly suggest that XLF is not essential for NHEJ but promotes LX adenylation and hence ligation. We propose a model in which XLF, by in situ recharging DNA ligase IV after the first ligation event, promotes double stranded ligation by a single LX complex. PMID:19056826

  20. Design and evaluation of a microgrid for PEV charging with flexible distribution of energy sources and storage

    Pyne, Moinak

    This thesis aspires to model and control, the flow of power in a DC microgrid. Specifically, the energy sources are a photovoltaic system and the utility grid, a lead acid battery based energy storage system and twenty PEV charging stations as the loads. Theoretical principles of large scale state space modeling are applied to model the considerable number of power electronic converters needed for controlling voltage and current thresholds. The energy storage system is developed using principles of neural networks to facilitate a stable and uncomplicated model of the lead acid battery. Power flow control is structured as a hierarchical problem with multiple interactions between individual components of the microgrid. The implementation is done using fuzzy logic with scheduling the maximum use of available solar energy and compensating demand or excess power with the energy storage system, and minimizing utility grid use, while providing multiple speeds of charging the PEVs.

  1. Probing the Origin of Neutrino Masses and Mixings via Doubly Charged Scalars: Complementarity of the Intensity and the Energy Frontiers

    Geib, Tanja; Merle, Alexander; No, Jose Miguel; Panizzi, Luca

    2015-01-01

    We discuss how the intensity and the energy frontiers provide complementary constraints within a minimal model of neutrino mass involving just one new field beyond the Standard Model at accessible energy, namely a doubly charged scalar $S^{++}$ and its antiparticle $S^{--}$. In particular we focus on the complementarity between high-energy LHC searches and low-energy probes such as lepton flavor violation. Our setting is a prime example of how high- and low-energy physics can cross-fertilize each other.

  2. Probing the origin of neutrino masses and mixings via doubly charged scalars: Complementarity of the intensity and the energy frontiers

    Geib, Tanja; King, Stephen F.; Merle, Alexander; No, Jose Miguel; Panizzi, Luca

    2016-04-01

    We discuss how the intensity and the energy frontiers provide complementary constraints within a minimal model of neutrino mass involving just one new field beyond the Standard Model at accessible energy, namely a doubly charged scalar S++ and its antiparticle S-- . In particular, we focus on the complementarity between high-energy LHC searches and low-energy probes such as lepton flavor violation. Our setting is a prime example of how high- and low-energy physics can cross-fertilize each other.

  3. Measurements of selected charge transfer processes at low energies. Final report, November 1977-November 1978

    Rutherford, J.A.; Neynaber, R.H.; Vroom, D.A.

    1978-11-01

    Measurement of the charge transfer cross section for the process N/sup +/ + O yields N + O/sup +/ was completed during the contract year. The experiment was conducted using a crossed beam apparatus. The O atoms were formed in a microwave or rf discharge using pure O/sub 2/ with traces of H/sub 2/O present. Varying the amount of H/sub 2/O present allowed the dissocation fraction in the O/sub 2/ to the varied. This variation was needed to allow determination of the effects of other competing processes. The cross section for the above reaction was determined in the energy range from 0.5 eV to 12 eV in the center-of-mass system. The signals obtained indicated that this process does not vary rapidly with energy. The cross section was determined to be 1.2 x 10/sup -17/ cm/sup 2/ at the lowest energies studied and increases to approximately 2.5 x 10/sup -17/ cm/sup 2/ at 12 eV in the center-of-mass. Cross sections for the reactions Al/sup +/ + O/sub 2/ yields AlO/sup +/ + O and Al + O/sub 2//sup +/ and Al/sup +/ + N/sub 2/ yields AlN/sup +/ + N and Al + N/sub 2//sup +/ were measured during the contract period. The values determined for these processes were essentially the same as those measured previously. In addition, the upper limits determined at energies where these processes have very small probabilities were pushed to lower values. The measurements were undertaken to resolve a conflict between our data and cross section values postulated to explain results obtained in another experiment.

  4. Charge and energy transfer by solitons in low-dimensional nanosystems with helical structure

    We study the nonlinear mechanism of the energy and charge transfer in low-dimensional nanosystems with helical structure. We show that the helical symmetry is important for the formation, stability and dynamical properties of the soliton-like self-trapped electron states. We obtain several types of stationary soliton solutions, namely single-band and hybrid two-band solitons which possess different energies. The two-band hybrid soliton spontaneously breaks the local translational and helical symmetries. For the values of the parameters of α-helical proteins this soliton possesses the lowest energy as compared with other types of solitons. This soliton has an inner structure which is manifested by a modulated multi-hump amplitude distribution of excitations on the individual strands of hydrogen bonds, identified in the helix. The displacement of such a soliton along the helix reveals distinctly the complex and composite structure of the soliton and causes oscillations of the energy distributions between the strands of hydrogen bonds. We show that the frequency of these oscillations is proportional to the soliton velocity. The radiative life-time of this hybrid soliton is calculated and shown to exceed by several orders of magnitude the life-time of a soliton excitation in a three-strand macromolecule without helical structure. The other two soliton solutions are formed by single-band states. These solitons preserve the helical symmetry, but in the α-helix they are dynamically unstable: once initially formed, they transform into the ground hybrid soliton state when propagating along the chain

  5. Charge and energy transfer by solitons in low-dimensional nanosystems with helical structure

    Brizhik, L. [Bogolyubov Institute for Theoretical Physics, 03143 Kyiv (Ukraine)], E-mail: brizhik@bitp.kiev.ua; Eremko, A. [Bogolyubov Institute for Theoretical Physics, 03143 Kyiv (Ukraine)], E-mail: eremko@bitp.kiev.ua; Piette, B. [Department of Mathematical Sciences, University of Durham, Durham DH1 3LE (United Kingdom)], E-mail: B.M.A.G.Piette@durham.ac.uk; Zakrzewski, W. [Department of Mathematical Sciences, University of Durham, Durham DH1 3LE (United Kingdom)], E-mail: W.J.Zakrzewski@durham.ac.uk

    2006-05-09

    We study the nonlinear mechanism of the energy and charge transfer in low-dimensional nanosystems with helical structure. We show that the helical symmetry is important for the formation, stability and dynamical properties of the soliton-like self-trapped electron states. We obtain several types of stationary soliton solutions, namely single-band and hybrid two-band solitons which possess different energies. The two-band hybrid soliton spontaneously breaks the local translational and helical symmetries. For the values of the parameters of {alpha}-helical proteins this soliton possesses the lowest energy as compared with other types of solitons. This soliton has an inner structure which is manifested by a modulated multi-hump amplitude distribution of excitations on the individual strands of hydrogen bonds, identified in the helix. The displacement of such a soliton along the helix reveals distinctly the complex and composite structure of the soliton and causes oscillations of the energy distributions between the strands of hydrogen bonds. We show that the frequency of these oscillations is proportional to the soliton velocity. The radiative life-time of this hybrid soliton is calculated and shown to exceed by several orders of magnitude the life-time of a soliton excitation in a three-strand macromolecule without helical structure. The other two soliton solutions are formed by single-band states. These solitons preserve the helical symmetry, but in the {alpha}-helix they are dynamically unstable: once initially formed, they transform into the ground hybrid soliton state when propagating along the chain.

  6. Determination of charge and energy for particles penetrating a silicon ΔExE telescope in space radiation

    A method of determination of charge and energy for energetic particles penetrating (not stopping) a multilayer silicon ΔExE telescope with a finite thickness (12mm) is examined in the energy region up to several hundreds of MeV/nucleon. From the results of the accelerator experiment, an energy resolution σE of 1.2% in rms and a charge resolution σZ of 0.11 charge unit in rms for Fe-group nuclei with energies between 190 and 230 MeV/nucleon are obtained. For lighter elements such as hydrogens and helium ions, an energy resolution σE of 2.9% is obtained in the energy region between 33 and 42 MeV/nucleon and even their individual isotopes are separated. Also, the energy dependences of these resolutions suggest that this method can be utilized for particles with energies about two times larger than that corresponding to the range of telescope thickness for the evaluation of the space radiation effects even under the limitations of weight, size, and electric power supply. (author)

  7. Charge equilibrium and radiation of low-energy cosmic rays passing through interstellar medium

    The charge equilibrium and radiation an oxygen and an iron beam in the MeV per nucleon energy range, representing a typical beam of low-energy cosmic rays passing through the interstellar medium, are considered. Electron loss of the beam has been taken into account by means of the first Born approximation allowing for the target atom to remain unexcited, or to be excited to all possible states. Electron-capture cross sections have been calculated by means of the scaled Oppenheimer-Brinkman-Kramers approximation, taking into account of atomic shells of the target atoms and capture into all excited states of the projectile. The capture and loss cross sections are found to be within 20%--30% of the existing experimental values for most of the cases considered. Radiation of the beam due to electron capture into the excited states of the ion, collisional excitation, and collisional inner-shell ionization, taking into account the fluorescence yield of the ions has been considered. Effective X-ray production cross sections and mutliplicities for the most energetic X-ray lines emitted by the Fe and O beams have been calculated, and error estimates made for the results

  8. Response of radiochromic dye films to low energy heavy charged particles

    Buenfil, A E; Gamboa-Debuen, I; Aviles, P; Avila, O; Olvera, C; Robledo, R; Rodriguez-Ponce, M; Mercado-Uribe, H; Rodriguez-Villafuerte, M; Brandan, M E

    2002-01-01

    We have studied the possible use of radiochromic dye films (RCF) as heavy charged particle dosemeters. We present the results of irradiating two commercial RCF (GafChromic HD-810 and MD-55-1) with 1.5, 2.9 and 4.4 MeV protons, 1.4, 2.8, 4.7, 5.9, 6.8 MeV sup 4 He ions and 8.5 and 12.4 MeV sup 1 sup 2 C ions, at proton doses from about 1 Gy up to 3 kGy, helium ions doses from 3 Gy to 5 kGy and carbon ion doses from 30 Gy to 20 kGy. The films were scanned and digitized using commercial equipment. For a given particle, the response per unit dose at different energies indicates an energy dependence of the sensitivity, which is discussed. Comparison was made for the use of a standard spectrophotometer to obtain optical density readings versus a white light scanner.

  9. Eikonal approximation in the theory of energy loss by fast charged particles

    Matveev, V. I.; Makarov, D. N.; Gusarevich, E. S.

    2011-05-01

    Energy losses in fast charged particles as a result of collisions with atoms are considered in the eikonal approximation. It is shown that the nonperturbative contribution to effective stopping in the range of intermediate impact parameters (comparable with the characteristic sizes of the electron shells of the target atoms) may turn out to be significant as compared to shell corrections to the Bethe-Bloch formula calculated in perturbation theory. The simplifying assumptions are formulated under which the Bethe-Bloch formula can be derived in the eikonal approximation. It is shown that the allowance for nonperturbative effects may lead to considerable (up to 50%) corrections to the Bethe-Bloch formula. The applicability range for the Bethe-Bloch formula is analyzed. It is concluded that calculation of the energy loss in the eikonal approximation (in the range of impact parameters for which the Bethe-Bloch formula is normally used) is much more advantageous than analysis based on the Bethe-Bloch formula and its modifications because not only the Bloch correction is included in the former calculations, the range of intermediate impact parameters is also taken into account nonperturbatively; in addition, direct generalization to the cases of collisions of complex projectiles and targets is possible in this case.

  10. Effect of bridge on energy transfer and photoinduced charge separation in perylene-diimide-naphthalene-bisimide-hexathiophene based donor-bridge-acceptor triads

    Tilley T.D.

    2013-03-01

    Full Text Available Femtosecond transient absorption spectroscopy is performed to assess bridge effects on energy transfer and charge separation in molecular junctions. A short, conjugated bridge can facilitate charge separation from both donor and acceptor, whereas in longer bridges charge separation only occurs from the excited donor.

  11. Three dimensional simulations of space charge dominated heavy ion beams with applications to inertial fusion energy

    Heavy ion fusion requires injection, transport and acceleration of high current beams. Detailed simulation of such beams requires fully self-consistent space charge fields and three dimensions. WARP3D, developed for this purpose, is a particle-in-cell plasma simulation code optimized to work within the framework of an accelerator's lattice of accelerating, focusing, and bending elements. The code has been used to study several test problems and for simulations and design of experiments. Two applications are drift compression experiments on the MBE-4 facility at LBL and design of the electrostatic quadrupole injector for the proposed ILSE facility. With aggressive drift compression on MBE-4, anomalous emittance growth was observed. Simulations carried out to examine possible causes showed that essentially all the emittance growth is result of external forces on the beam and not of internal beam space-charge fields. Dominant external forces are the dodecapole component of focusing fields, the image forces on the surrounding pipe and conductors, and the octopole fields that result from the structure of the quadrupole focusing elements. Goal of the design of the electrostatic quadrupole injector is to produce a beam of as low emittance as possible. The simulations show that the dominant effects that increase the emittance are the nonlinear octopole fields and the energy effect (fields in the axial direction that are off-axis). Injectors were designed that minimized the beam envelope in order to reduce the effect of the nonlinear fields. Alterations to the quadrupole structure that reduce the nonlinear fields further were examined. Comparisons were done with a scaled experiment resulted in very good agreement

  12. Three dimensional simulations of space charge dominated heavy ion beams with applications to inertial fusion energy

    Grote, D.P.

    1994-11-01

    Heavy ion fusion requires injection, transport and acceleration of high current beams. Detailed simulation of such beams requires fully self-consistent space charge fields and three dimensions. WARP3D, developed for this purpose, is a particle-in-cell plasma simulation code optimized to work within the framework of an accelerator`s lattice of accelerating, focusing, and bending elements. The code has been used to study several test problems and for simulations and design of experiments. Two applications are drift compression experiments on the MBE-4 facility at LBL and design of the electrostatic quadrupole injector for the proposed ILSE facility. With aggressive drift compression on MBE-4, anomalous emittance growth was observed. Simulations carried out to examine possible causes showed that essentially all the emittance growth is result of external forces on the beam and not of internal beam space-charge fields. Dominant external forces are the dodecapole component of focusing fields, the image forces on the surrounding pipe and conductors, and the octopole fields that result from the structure of the quadrupole focusing elements. Goal of the design of the electrostatic quadrupole injector is to produce a beam of as low emittance as possible. The simulations show that the dominant effects that increase the emittance are the nonlinear octopole fields and the energy effect (fields in the axial direction that are off-axis). Injectors were designed that minimized the beam envelope in order to reduce the effect of the nonlinear fields. Alterations to the quadrupole structure that reduce the nonlinear fields further were examined. Comparisons were done with a scaled experiment resulted in very good agreement.

  13. Charge-dependent and A-dependent effects in isotope shifts of Coulomb displacement energies

    Coulomb displacement energies in a series of isotopes generally decrease with A. This decrease can arise from an increase with A of the average distance of interaction between pairs of protons. In the shell model a decrease can also result from charge-independence-breaking effects if the neutron-proton interaction for the valence nucleons is more attractive than the neutron-neutron interaction. Using the model recently proposed by Sherr and Talmi for the 1d/sub 3/2/ shell, existing data for this shell and also the 1d/sub 5/2/ and 1f/sub 7/2/ shells were analyzed allowing all matrix elements to vary as A/sup -lambda/3/. Least squares calculations of the rms deviation sigma were carried out for varying values of lambda from -2 to +2. It was found that although there was a minimum in sigma vs lambda it was too shallow to exclude any lambda for -1 to +1 in the 1d/sub 3/2/ and 1f/sub 7/2/ shells or 0 to +1 in the 1d/sub 5/2/ shell. It is therefore not possible to distinguish between A dependence and charge dependence in this model. The magnitude of the latter as expressed in terms of (np-nn) matrix elements depends strongly on the former. As lambda increases from -1 to +1, these (np-nn) matrix elements decrease roughly linearly in absolute magnitude and eventually change sign. For lambda = 0 they have appreciable and reasonable magnitudes for the 1d/sub 3/2/ and 1f/sub 7/2/ shells but for the 1d/sub 5/2/ shell the values are too small to be considered significant

  14. Cation Recombination Energy/Coulomb Repulsion Effects in ETD/ECD as Revealed by Variation of Charge per Residue at Fixed Total Charge

    Mentinova, Marija; Crizer, David M.; Baba, Takashi; McGee, William M.; Glish, Gary L.; McLuckey, Scott A.

    2013-11-01

    Electron capture dissociation (ECD) and electron transfer dissociation (ETD) experiments in electrodynamic ion traps operated in the presence of a bath gas in the 1-10 mTorr range have been conducted on a common set of doubly protonated model peptides of the form X(AG)nX (X = lysine, arginine, or histidine, n = 1, 2, or 4). The partitioning of reaction products was measured using thermal electrons, anions of azobenzene, and anions of 1,3-dinitrobenzene as reagents. Variation of n alters the charge per residue of the peptide cation, which affects recombination energy. The ECD experiments showed that H-atom loss is greatest for the n = 1 peptides and decreases as n increases. Proton transfer in ETD, on the other hand, is expected to increase as charge per residue decreases (i.e., as n increases). These opposing tendencies were apparent in the data for the K(AG)nK peptides. H-atom loss appeared to be more prevalent in ECD than in ETD and is rationalized on the basis of either internal energy differences, differences in angular momentum transfer associated with the electron capture versus electron transfer processes, or a combination of the two. The histidine peptides showed the greatest extent of charge reduction without dissociation, the arginine peptides showed the greatest extent of side-chain cleavages, and the lysine peptides generally showed the greatest extent of partitioning into the c/z•-product ion channels. The fragmentation patterns for the complementary c- and z•-ions for ETD and ECD were found to be remarkably similar, particularly for the peptides with X = lysine.

  15. Charge-exchange, ionization and excitation in low-energy Li$^{+}-$ Ar, K$^{+}-$ Ar, and Na$^{+}-$He collisions

    Lomsadze, Ramaz A; Kezerashvili, RomanYa; Schulz, Michael

    2016-01-01

    Absolute cross sections are measured for charge-exchange, ionization, and excitation within the same experimental setup for the Li$^{+}-$Ar, K$^{+}-$ Ar, and Na$^{+}-$ He collisions in the ion energy range $0.5-10$ keV. Results of our measurements along with existing experimental data and the schematic correlation diagrams are used to analyze and determine the mechanisms for these processes. The experimental results show that the charge-exchange processes are realized with high probabilities and electrons are predominately captured in ground states. The cross section ratio for charge exchange, ionization and excitation processes roughly attains the value $10:2:1$, respectively. The contributions of various partial inelastic channels to the total ionization cross sections are estimated and a primary mechanism for the process is defined. The energy-loss spectrum, in addition, is applied to estimate the relative contribution of different inelastic channels and to determine the mechanisms for the ionization and f...

  16. On the fast multipole method for computing the energy of periodic assemblies of charged and dipolar particles

    In two dimensions, it is convenient to represent the coordinates (x, y) of particles as complex numbers z = x + iy. The energy of interaction of two point charges q1 and q 2 at points represented by the complex numbers z1 and z2 is then since the natural logarithm is the singular part of the Greens function for the two-dimensional Laplace equation. In performing molecular dynamics and Monte Carlo simulations of neutral systems of charged particles or of point dipoles, it is necessary to compute the energies and forces of an infinite periodic system in which the N charges or dipoles at the points z1 ... zn resident in the primary (usually square) simulation cell are replicated everywhere in the plane

  17. Charge-state dependence of energy loss of MeV dimers in GaAs(100)

    Carbon and oxygen dimers with charge states 1+ and 3+ were implanted into GaAs along the [100] direction at an energy of 0.5 MeV/atom. The defect depth profiles are extracted from Rutherford backscattering spectrometry and channeling. The depth profile of carbon is extracted from secondary ion mass spectrometry measurements. The defect density produced by dimer ions is larger than monomer ions. The depth profile of carbon in dimer implanted GaAs is deeper than that of monomer implanted GaAs showing negative molecular effect. The defect depth profile of oxygen dimer implanted GaAs is deeper for 3+ than that for 1+ charge state. This indicates that energy loss of O23+ is smaller than that of O2+. It is attributed to charge asymmetry and a higher degree of alignment of O23+ along the [100] axis of GaAs

  18. Interplay of low-energy bosonic collective modes with incipient charge order in Bi-2212 characterized by momentum-resolved electron energy loss spectroscopy

    Vig, Sean; Kogar, Anshul; Mishra, Vivek; Rak, Melinda; Husain, Ali; Gu, Genda; Norman, Mike; Abbamonte, Peter

    Classifying the collective electronic dynamics of materials is critical to addressing the high temperature superconductivity problem and understanding related collective phenomena. Most current probes are unable to measure the full energy and momentum dependence of the dynamic charge susceptibility in these strongly correlated materials at the meV energy scale relevant to superconductivity. We use our momentum-resolved electron energy loss spectroscopy (M-EELS) technique to perform this measurement, characterizing both the static charge density and the bosonic electronic excitations in the cuprate superconductor Bi2SrCaCu2O8+δ (Bi-2212). I present our measurement of a low temperature diffuse charge ordered state at optimal doping which modulates the observed dispersionless low energy collective excitations. Performing a one-loop correction to the bare electron dispersion, we show these modes reproduce the self-energy anomaly, or ``kink'', as measured by ARPES. I discuss the nature of the charge dynamics that we measured with our technique and its relation to the superconducting state. This work was supported as part of the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science.

  19. Reconstitution of the GTP-dependent adenylate cyclase from products of the yeast CYR1 and RAS2 genes in Escherichia coli.

    Uno, I.; Mitsuzawa, H.; Matsumoto, K.; Tanaka, K; Oshima, T.; Ishikawa, T

    1985-01-01

    Plasmids carrying the CYR1 gene of yeast Saccharomyces cerevisiae, which encodes adenylate cyclase, were introduced into the cya mutant strain of Escherichia coli. The transformants had a GTP-independent adenylate cyclase activity but did not produce cAMP. The E. coli transformant carrying the yeast RAS2 or RAS2val19 gene had no adenylate cyclase activity. Transformant cells carrying both CYR1 and RAS2 produced GTP-dependent adenylate cyclase and cAMP, and those carrying CYR1 and RAS2val19 pr...

  20. How High Local Charge Carrier Mobility and an Energy Cascade in a Three-Phase Bulk Heterojunction Enable >90% Quantum Efficiency

    Burke, Timothy M.

    2013-12-27

    Charge generation in champion organic solar cells is highly efficient in spite of low bulk charge-carrier mobilities and short geminate-pair lifetimes. In this work, kinetic Monte Carlo simulations are used to understand efficient charge generation in terms of experimentally measured high local charge-carrier mobilities and energy cascades due to molecular mixing. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. On the Komar Energy and the Generalized Smarr Formula for a Charged Black Hole of Noncommutative Geometry

    Larranaga, Alexis; Jimenez, Juan Carlos

    2012-01-01

    We calculate the Komar energy $E$ for a charged black hole inspired by noncommutative geometry and identify the total mass ($M_{0}$) by considering the asymptotic limit. We also found the generalized Smarr formula, which shows a deformation from the well known relation $M_{0}-\\frac{Q_{0}^{2}}{r}=2ST$ depending on the noncommutative scale length $\\ell$ .

  2. Charge deep-level transient spectroscopy study of high-energy-electron-beam-irradiated hydrogenated amorphous silicon

    Klaver, A.; Nádaždy, V.; Zeman, M.; Swaaiij, R.A.C.M.M.

    2006-01-01

    We present a study of changes in the defect density of states in hydrogenated amorphous silicon (a-Si:H) due to high-energy electron irradiation using charged deep-level transient spectroscopy. It was found that defect states near the conduction band were removed, while in other band gap regions the

  3. Coherence, energy and charge transfers in de-excitation pathways of electronic excited state of biomolecules in photosynthesis

    Bohr, Henrik; Malik, F. Bary

    2013-01-01

    The observed multiple de-excitation pathways of photo-absorbed electronic excited state in the peridinin–chlorophyll complex, involving both energy and charge transfers among its constituents, are analyzed using the bio-Auger (B-A) theory. It is also shown that the usually used F¨orster–Dexter...

  4. Charge versus Energy Transfer Effects in High-Performance Perylene Diimide Photovoltaic Blend Films.

    Singh, Ranbir; Shivanna, Ravichandran; Iosifidis, Agathaggelos; Butt, Hans-Jürgen; Floudas, George; Narayan, K S; Keivanidis, Panagiotis E

    2015-11-11

    Perylene diimide (PDI)-based organic photovoltaic devices can potentially deliver high power conversion efficiency values provided the photon energy absorbed is utilized efficiently in charge transfer (CT) reactions instead of being consumed in nonradiative energy transfer (ET) steps. Hitherto, it remains unclear whether ET or CT primarily drives the photoluminescence (PL) quenching of the PDI excimer state in PDI-based blend films. Here, we affirm the key role of the thermally assisted PDI excimer diffusion and subsequent CT reaction in the process of PDI excimer PL deactivation. For our study we perform PL quenching experiments in the model PDI-based composite made of poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b']dithiophene-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiophene)-2-6-diyl] (PBDTTT-CT) polymeric donor mixed with the N,N'-bis(1-ethylpropyl)-perylene-3,4,9,10-tetracarboxylic diimide (PDI) acceptor. Despite the strong spectral overlap between the PDI excimer PL emission and UV-vis absorption of PBDTTT-CT, two main observations indicate that no significant ET component operates in the overall PL quenching: the PL intensity of the PDI excimer (i) increases with decreasing temperature and (ii) remains unaffected even in the presence of 10 wt % content of the PBDTTT-CT quencher. Temperature-dependent wide-angle X-ray scattering experiments further indicate that nonradiative resonance ET is highly improbable due to the large size of PDI domains. The dominance of the CT over the ET process is verified by the high performance of devices with an optimum composition of 30:70 PBDTTT-CT:PDI. By adding 0.4 vol % of 1,8-diiodooctane we verify the plasticization of the polymer side chains that balances the charge transport properties of the PBDTTT-CT:PDI composite and results in additional improvement in the device efficiency. The temperature-dependent spectral width of the PDI excimer PL band suggests the presence of energetic disorder in the

  5. Workplace Charging. Charging Up University Campuses

    Giles, Carrie [ICF International, Fairfax, VA (United States); Ryder, Carrie [ICF International, Fairfax, VA (United States); Lommele, Stephen [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-01

    This case study features the experiences of university partners in the U.S. Department of Energy's (DOE) Workplace Charging Challenge with the installation and management of plug-in electric vehicle (PEV) charging stations.

  6. Study of the charge kinetics of MgO (1 1 0) subjected to high energy electron irradiation

    Boughariou, A., E-mail: aicha_boughariou@yahoo.fr [LaMaCoP, Université de Sfax pour le sud, Faculté des Sciences, 3038 Sfax Tunisie (Tunisia); Kallel, A. [LaMaCoP, Université de Sfax pour le sud, Faculté des Sciences, 3038 Sfax Tunisie (Tunisia); Blaise, G. [LPS, Université Paris-Sud XI, Batiment 510, Orsay 91405 (France)

    2014-09-15

    Highlights: • Variation of the logarithm of SEE yield with the injected dose in MgO (1 1 0) at high energy. • Critical energy E{sub C} of MgO (1 1 0). • Formation of an electrostatic mirror. • Breakdown phenomenon (current density effect). - Abstract: This article presents a study performed with a dedicated scanning electron microscope (SEM) on the electrical property evolution of magnesium oxide (1 1 0) single crystal during 15 and 30 keV irradiation. First, the charging behavior is studied during the charge injection process at low current density J{sub 0}, by measuring the logarithm of the secondary electron emission yield (lnσ). Next, we have investigated the dependence on the current density of the charge-trapping phenomena in MgO (1 1 0). The results shown that beyond the crossover energy E{sub 2}, the observed effects varies depending on whether the energy of the primary electrons is lower or higher than an energy called critical energy E{sub c} = 20 keV (in the case of MgO (1 1 0)). When irradiating the material at E{sub 0} < E{sub c} and at low J{sub 0}, self regulated regime is obtained, if J{sub 0} is sufficiently intense an aging regime is reached. This latter regime is characterized by a positive surface charge, when a negative charge was expected. At E{sub 0} > E{sub c}, and for low J{sub 0}, the detailed monitoring of the charge kinetic of MgO (1 1 0) at high primary energy E{sub 0} = 30 keV, permit to show that the combined effect of the increased negative surface potential during irradiation and extractor field below the surface of MgO fact that lnσ undergoes a strong slope failure at the beginning of the injection and stabilizes at a value much less than zero leading to the formation of an electrostatic mirror. At high J{sub 0}, the consequences of the charge accumulation are violent and a breakdown phenomenon is observed.

  7. Study of the charge kinetics of MgO (1 1 0) subjected to high energy electron irradiation

    Highlights: • Variation of the logarithm of SEE yield with the injected dose in MgO (1 1 0) at high energy. • Critical energy EC of MgO (1 1 0). • Formation of an electrostatic mirror. • Breakdown phenomenon (current density effect). - Abstract: This article presents a study performed with a dedicated scanning electron microscope (SEM) on the electrical property evolution of magnesium oxide (1 1 0) single crystal during 15 and 30 keV irradiation. First, the charging behavior is studied during the charge injection process at low current density J0, by measuring the logarithm of the secondary electron emission yield (lnσ). Next, we have investigated the dependence on the current density of the charge-trapping phenomena in MgO (1 1 0). The results shown that beyond the crossover energy E2, the observed effects varies depending on whether the energy of the primary electrons is lower or higher than an energy called critical energy Ec = 20 keV (in the case of MgO (1 1 0)). When irradiating the material at E0 < Ec and at low J0, self regulated regime is obtained, if J0 is sufficiently intense an aging regime is reached. This latter regime is characterized by a positive surface charge, when a negative charge was expected. At E0 > Ec, and for low J0, the detailed monitoring of the charge kinetic of MgO (1 1 0) at high primary energy E0 = 30 keV, permit to show that the combined effect of the increased negative surface potential during irradiation and extractor field below the surface of MgO fact that lnσ undergoes a strong slope failure at the beginning of the injection and stabilizes at a value much less than zero leading to the formation of an electrostatic mirror. At high J0, the consequences of the charge accumulation are violent and a breakdown phenomenon is observed

  8. Triboelectric-Potential-Regulated Charge Transport Through p-n Junctions for Area-Scalable Conversion of Mechanical Energy.

    Meng, Xian Song; Wang, Zhong Lin; Zhu, Guang

    2016-01-27

    Regulation of charge-transport direction is realized through the coupling of triboelectrification, electrostatic induction, and semiconducting properties for area-scalable conversion of mechanical energy. The output current from each unit triboelectric generator can always constructively add up due to the unidirectional flow of electrons. This work proposes a practical and general route to area-scalable applications of the triboelectric generator and other energy-harvesting techniques. PMID:26611707

  9. IMPROVING ENERGY EFFICIENCY VIA OPTIMIZED CHARGE MOTION AND SLURRY FLOW IN PLANT SCALE SAG MILLS

    Raj K. Rajamani; Sanjeeva Latchireddi; Sravan K. Prathy; Trilokyanath Patra

    2005-12-01

    The U.S. mining industry operates approximately 80 semi-autogenesis grinding mills (SAG) throughout the United States. Depending on the mill size the SAG mills draws between 2 MW and 17 MW. The product from the SAG mill is further reduced in size using pebble crushers and ball mills. Hence, typical gold or copper ore requires between 2.0 and 7.5 kWh per ton of energy to reduce the particle size. Considering a typical mining operation processes 10,000 to 100,000 tons per day the energy expenditure in grinding is 50 percent of the cost of production of the metal. A research team from the University of Utah is working to make inroads into saving energy in these SAG mills. In 2003, Industries of the Future Program of the Department of Energy tasked the University of Utah team to build a partnership between the University and the mining industry for the specific purpose of reducing energy consumption in SAG mills. A partnership was formed with Cortez Gold Mines, Kennecott Utah Copper Corporation, Process Engineering Resources Inc. and others. In the current project, Cortez Gold Mines played a key role in facilitating the 26-ft SAG mill at Cortez as a test mill for this study. According to plant personnel, there were a number of unscheduled shut downs to repair broken liners and the mill throughput fluctuated depending on ore type. The University team had two softwares, Millsoft and FlowMod to tackle the problem. Millsoft is capable of simulating the motion of charge in the mill. FlowMod calculates the slurry flow through the grate and pulp lifters. Based on this data the two models were fine-tuned to fit the Cortez SAG will. In the summer of 2004 a new design of shell lifters were presented to Cortez and in September 2004 these lifters were installed in the SAG mill. By December 2004 Cortez Mines realized that the SAG mill is drawing approximately 236-kW less power than before while maintaining the same level of production. In the first month there was extreme cycling

  10. Studies on density dependence of charge separation in a direct energy converter using slanted Cusp magnetic field

    In an advanced fusion, fusion-produced charged particles must be separated from each other for efficient energy conversion to electricity. The CuspDEC performs this function of separation and direct energy conversion. Analysis of working characteristics of CuspDEC on plasma density is an important subject. This paper summarizes and discusses experimental and theoretical works for high density plasma by using a small scale experimental device employing a slanted cusp magnetic field. When the incident plasma is low-density, good separation of the charged particles can be accomplished and this is explained by the theory based on a single particle motion. In high density plasma, however, this theory cannot be always applied due to space charge effects. In the experiment, as gradient of the field line increases, separation capability of the charged particles becomes higher. As plasma density becomes higher, however, separation capability becomes lower. This can be qualitatively explained by using calculations of the modified Störmer potential including space charge potential. (author)

  11. Beam hardening artefacts in computed tomography with photon counting, charge integrating and energy weighting detectors: a simulation study

    Shikhaliev, Polad M [Department of Radiological Sciences, University of California, Irvine, CA 92697 (United States)

    2005-12-21

    Photon counting x-ray imaging provides efficient rejection of the electronics noise, no pulse height (Swank) noise, less noise due to optimal photon energy weighting and the possibility of energy resolved image acquisition. These advantages apply also to CT when projection data are acquired using a photon counting detector. However, photon counting detectors assign a weighting factor of 1 to all detected photons whereas the weighting factor of a charge integrating detector is proportional to the energy of the detected photon. Therefore, data collected by photon counting and charge integrating detectors represent the 'hardening' of the photon beam passed through the object differently. This affects the beam hardening artefacts in the reconstructed CT images. This work represents the first comparative evaluation of the effect of photon counting, charge integrating and energy weighting photon detectors on beam hardening artefacts in CT. Beam hardening artefacts in CT images were evaluated for 20 cm and 14 cm diameter water cylinders with bone and low contrast inserts, at 120 kVp and 90 kVp x-ray tube voltages, respectively. It was shown that charge integrating results in 1.8% less beam hardening artefacts from bone inserts (i.e., CT numbers in the 'shadow' of the bone are less by 1.8% as compared to CT numbers over the periphery of the image), as compared to photon counting. However, optimal photon energy weighting, which provides highest SNR, results in 7.7% higher beam hardening artefacts from bone inserts as compared to photon counting. The magnitude of the 'cupping' artefacts was lower by 1% for charge integrating and higher by 6.1% for energy weighting acquisitions as compared to photon counting. Only the photon counting systems provide an accurate representation of the beam hardening effect due to its flat energy weighting. Because of their energy dependent weighting factors, the charge integrating and energy weighting systems do

  12. Impacts of side chain and excess energy on the charge photogeneration dynamics of low-bandgap copolymer-fullerene blends.

    Huo, Ming-Ming; Hu, Rong; Xing, Ya-Dong; Liu, Yu-Chen; Ai, Xi-Cheng; Zhang, Jian-Ping; Hou, Jian-Hui

    2014-02-28

    Primary charge photogeneration dynamics in neat and fullerene-blended films of a pair of alternating benzo[1,2-b:4,5-b(')]dithiophene (BDT) and thieno[3,4-b]thiophene (TT) copolymers are comparatively studied by using near-infrared, time-resolved absorption (TA) spectroscopy under low excitation photon fluence. PBDTTT-E and PBDTTT-C, differed merely in the respective TT-substituents of ester (-E) and carbonyl (-C), show distinctly different charge photogeneration dynamics. The pair of neat PBDTTT films show exciton lifetimes of ∼0.1 ns and fluorescence quantum yields below 0.2%, as well as prominent excess-energy enhanced exciton dissociation. In addition, PBDTTT-C gives rise to >50% higher P(•+) yield than PBDTTT-E does irrespective to the excitation photon energy. Both PBDTTT-E:PC61BM and PBDTTT-C:PC61BM blends show subpicosecond exciton lifetimes and nearly unitary fluorescence quenching efficiency and, with respect to the former blend, the latter one shows substantially higher branching ratio of charge separated (CS) state over interfacial charge transfer (ICT) state, and hence more efficient exciton-to-CS conversion. For PBDTTT-C:PC61BM, the ultrafast charge dynamics clearly show the processes of ICT-CS interconversion and P(•+) migration, which are possibly influenced by the ICT excess energy. However, such processes are relatively indistinctive in the case of PBDTTT-E:PC61BM. The results strongly prove the importance of ICT dissociation in yielding free charges, and are discussed in terms of the film morphology and the precursory solution-phase macromolecular conformation. PMID:24588194

  13. Impacts of side chain and excess energy on the charge photogeneration dynamics of low-bandgap copolymer-fullerene blends

    Huo, Ming-Ming, E-mail: hithuomm@163.com; Zhang, Jian-Ping, E-mail: jpzhang@chem.ruc.edu.cn, E-mail: hjhzlz@iccas.ac.cn [Center for Condensed Matter Science and Technology, Department of Physics, Harbin Institute of Technology, Harbin 150001 (China); Department of Chemistry, Renmin University of China, Beijing 100872 (China); Hu, Rong, E-mail: hurong-82@163.com; Xing, Ya-Dong, E-mail: xingyadong1130@126.com; Liu, Yu-Chen, E-mail: liuych@ruc.edu.cn; Ai, Xi-Cheng, E-mail: xcai@chem.ruc.edu.cn [Department of Chemistry, Renmin University of China, Beijing 100872 (China); Hou, Jian-Hui, E-mail: jpzhang@chem.ruc.edu.cn, E-mail: hjhzlz@iccas.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-02-28

    Primary charge photogeneration dynamics in neat and fullerene-blended films of a pair of alternating benzo[1,2-b:4,5-b{sup ′}]dithiophene (BDT) and thieno[3,4-b]thiophene (TT) copolymers are comparatively studied by using near-infrared, time-resolved absorption (TA) spectroscopy under low excitation photon fluence. PBDTTT-E and PBDTTT-C, differed merely in the respective TT-substituents of ester (-E) and carbonyl (-C), show distinctly different charge photogeneration dynamics. The pair of neat PBDTTT films show exciton lifetimes of ∼0.1 ns and fluorescence quantum yields below 0.2%, as well as prominent excess-energy enhanced exciton dissociation. In addition, PBDTTT-C gives rise to >50% higher P{sup •+} yield than PBDTTT-E does irrespective to the excitation photon energy. Both PBDTTT-E:PC{sub 61}BM and PBDTTT-C:PC{sub 61}BM blends show subpicosecond exciton lifetimes and nearly unitary fluorescence quenching efficiency and, with respect to the former blend, the latter one shows substantially higher branching ratio of charge separated (CS) state over interfacial charge transfer (ICT) state, and hence more efficient exciton-to-CS conversion. For PBDTTT-C:PC{sub 61}BM, the ultrafast charge dynamics clearly show the processes of ICT-CS interconversion and P{sup •+} migration, which are possibly influenced by the ICT excess energy. However, such processes are relatively indistinctive in the case of PBDTTT-E:PC{sub 61}BM. The results strongly prove the importance of ICT dissociation in yielding free charges, and are discussed in terms of the film morphology and the precursory solution-phase macromolecular conformation.

  14. Charge exchange and energy loss of slowed down heavy ions channeled in silicon crystals; Echanges de charge et perte d'energie d'ions lourds ralentis, canalises dans des cristaux de silicium

    Testa, E

    2005-10-15

    This work is devoted to the study of charge exchange processes and of the energy loss of highly charged heavy ions channeled in thin silicon crystals. The two first chapters present the techniques of heavy ion channeling in a crystal, the ion-electron processes and the principle of our simulations (charge exchange and trajectory of channeled ions). The next chapters describe the two experiments performed at the GSI facility in Darmstadt, the main results of which follow: the probability per target atom of the mechanical capture (MEC) of 20 MeV/u U{sup 91+} ions as a function of the impact parameter (with the help of our simulations), the observation of the strong polarization of the target electron gas by the study of the radiative capture and the slowing down of Pb{sup 81+} ions from 13 to 8,5 MeV/u in channeling conditions for which electron capture is strongly reduced. (author)

  15. Orientation dependence of the probability of close collisions during passage of high-energy negatively charged particle through a bent crystal

    The probability of close collisions of high-energy negatively charged particle with atoms in a bent crystal was considered as a function of the angle between the initial particle momentum and the bending plane. This allowed to compare the probability of close collisions of high-energy negatively charged particle in a bent crystal in two different regimes of deflection: planar channeling and stochastic deflection. The results of simulation of negatively charged particle motion in a bent crystal shown the great efficiency of high-energy negatively charged particle beam deflection by a bent crystal due to stochastic deflection and small efficiency of deflection due to planar channeling

  16. High throughput on-chip analysis of high-energy charged particle tracks using lensfree imaging

    We demonstrate a high-throughput charged particle analysis platform, which is based on lensfree on-chip microscopy for rapid ion track analysis using allyl diglycol carbonate, i.e., CR-39 plastic polymer as the sensing medium. By adopting a wide-area opto-electronic image sensor together with a source-shifting based pixel super-resolution technique, a large CR-39 sample volume (i.e., 4 cm × 4 cm × 0.1 cm) can be imaged in less than 1 min using a compact lensfree on-chip microscope, which detects partially coherent in-line holograms of the ion tracks recorded within the CR-39 detector. After the image capture, using highly parallelized reconstruction and ion track analysis algorithms running on graphics processing units, we reconstruct and analyze the entire volume of a CR-39 detector within ∼1.5 min. This significant reduction in the entire imaging and ion track analysis time not only increases our throughput but also allows us to perform time-resolved analysis of the etching process to monitor and optimize the growth of ion tracks during etching. This computational lensfree imaging platform can provide a much higher throughput and more cost-effective alternative to traditional lens-based scanning optical microscopes for ion track analysis using CR-39 and other passive high energy particle detectors

  17. High throughput on-chip analysis of high-energy charged particle tracks using lensfree imaging

    Luo, Wei; Shabbir, Faizan; Gong, Chao; Gulec, Cagatay; Pigeon, Jeremy; Shaw, Jessica; Greenbaum, Alon; Tochitsky, Sergei; Joshi, Chandrashekhar [Electrical Engineering Department, University of California, Los Angeles, California 90095 (United States); Ozcan, Aydogan, E-mail: ozcan@ucla.edu [Electrical Engineering Department, University of California, Los Angeles, California 90095 (United States); Bioengineering Department, University of California, Los Angeles, California 90095 (United States); California NanoSystems Institute (CNSI), University of California, Los Angeles, California 90095 (United States)

    2015-04-13

    We demonstrate a high-throughput charged particle analysis platform, which is based on lensfree on-chip microscopy for rapid ion track analysis using allyl diglycol carbonate, i.e., CR-39 plastic polymer as the sensing medium. By adopting a wide-area opto-electronic image sensor together with a source-shifting based pixel super-resolution technique, a large CR-39 sample volume (i.e., 4 cm × 4 cm × 0.1 cm) can be imaged in less than 1 min using a compact lensfree on-chip microscope, which detects partially coherent in-line holograms of the ion tracks recorded within the CR-39 detector. After the image capture, using highly parallelized reconstruction and ion track analysis algorithms running on graphics processing units, we reconstruct and analyze the entire volume of a CR-39 detector within ∼1.5 min. This significant reduction in the entire imaging and ion track analysis time not only increases our throughput but also allows us to perform time-resolved analysis of the etching process to monitor and optimize the growth of ion tracks during etching. This computational lensfree imaging platform can provide a much higher throughput and more cost-effective alternative to traditional lens-based scanning optical microscopes for ion track analysis using CR-39 and other passive high energy particle detectors.

  18. Charge neutralized low energy beam transport at Brookhaven 200 MeV linac

    Raparia, D., E-mail: raparia@bnl.gov; Alessi, J.; Atoian, G.; Zelenski, A. [Brookhaven National Laboratory, Upton, New York 11786 (United States)

    2016-02-15

    The H{sup −} magnetron source provides about 100 mA H{sup −} beam to be match into the radio-frequency quadrupole accelerator. As H{sup −} beam traverses through low energy transport, it ionizes the residual gas and electrons are repelled and positive ions are trapped in the beam, due to negative potential of the beam, providing charge neutralization for the H{sup −} beam. The neutralization time for the critical density depends upon the background gas and its pressure. Critical density for xenon gas at 35 keV is about 43 times smaller than that of hydrogen and stripping cross section is only 5 times than that of hydrogen gas. We are using xenon gas to reduce neutralization time and to improve transmission through the 200 MeV linac. We are also using pulse nitrogen gas to improve transmission and stability of polarized H{sup −} beam from optically pumped polarized ion source.

  19. Effect of charging energy on critical current of dc-SQUID comprising two sub-micron aluminum Josephson junctions

    Highlights: ► We measure the capacitance of Al Josephson junctions by using the dc-SQUID methods. ► Both the Josephson coupling energy and charging energy in the SQUID are evaluated. ► The interference pattern is found to be deviated from the classical theory. ► The deviation is enhanced by decreasing the Josephson coupling energy. ► Our model including the quantum phase fluctuation can explain the deviation. -- Abstract: Tiny Al/AlOx/Al tunnel junctions are widely used in single-electron, single-Cooper-pair, and quantum-bit devices. A crucial parameter for such devices is the charging energy of a single electron or a single Cooper-pair in the junctions, and hence, determination of the junction capacitance is quite important. In this paper, we report our experiments to determine the capacitance of sub-micron Al tunnel junctions. We employ a SQUID resonance technique. Differently from the work reported by Deppe et al. [4], the loop inductance is obtained by not only numerical calculation but also experimental results of quantum interference, which eliminates uncertainty about the field penetration depth of Al thin films. The specific capacitance is obtained as 54 fF/μm2. We have also found that the critical current of the dc-SQUID is smaller than the value given by the classical theory for large Josephson junctions. Calculation including the charging energy effect provides better fitting to the experiments, where the critical current is assumed to be proportional to the square root of the ratio of the Josephson coupling energy to the charging energy

  20. A minor conformation of a lanthanide tag on adenylate kinase characterized by paramagnetic relaxation dispersion NMR spectroscopy

    Hass, Mathias A. S.; Liu, Wei-Min [Leiden University, Leiden Institute of Chemistry (Netherlands); Agafonov, Roman V.; Otten, Renee; Phung, Lien A. [Brandeis University, Department of Biochemistry, Howard Hughes Medical Institute (United States); Schilder, Jesika T. [Leiden University, Leiden Institute of Chemistry (Netherlands); Kern, Dorothee [Brandeis University, Department of Biochemistry, Howard Hughes Medical Institute (United States); Ubbink, Marcellus, E-mail: m.ubbink@chem.leidenuniv.nl [Leiden University, Leiden Institute of Chemistry (Netherlands)

    2015-02-15

    NMR relaxation dispersion techniques provide a powerful method to study protein dynamics by characterizing lowly populated conformations that are in dynamic exchange with the major state. Paramagnetic NMR is a versatile tool for investigating the structures and dynamics of proteins. These two techniques were combined here to measure accurate and precise pseudocontact shifts of a lowly populated conformation. This method delivers valuable long-range structural restraints for higher energy conformations of macromolecules in solution. Another advantage of combining pseudocontact shifts with relaxation dispersion is the increase in the amplitude of dispersion profiles. Lowly populated states are often involved in functional processes, such as enzyme catalysis, signaling, and protein/protein interactions. The presented results also unveil a critical problem with the lanthanide tag used to generate paramagnetic relaxation dispersion effects in proteins, namely that the motions of the tag can interfere severely with the observation of protein dynamics. The two-point attached CLaNP-5 lanthanide tag was linked to adenylate kinase. From the paramagnetic relaxation dispersion only motion of the tag is observed. The data can be described accurately by a two-state model in which the protein-attached tag undergoes a 23° tilting motion on a timescale of milliseconds. The work demonstrates the large potential of paramagnetic relaxation dispersion and the challenge to improve current tags to minimize relaxation dispersion from tag movements.

  1. A minor conformation of a lanthanide tag on adenylate kinase characterized by paramagnetic relaxation dispersion NMR spectroscopy

    NMR relaxation dispersion techniques provide a powerful method to study protein dynamics by characterizing lowly populated conformations that are in dynamic exchange with the major state. Paramagnetic NMR is a versatile tool for investigating the structures and dynamics of proteins. These two techniques were combined here to measure accurate and precise pseudocontact shifts of a lowly populated conformation. This method delivers valuable long-range structural restraints for higher energy conformations of macromolecules in solution. Another advantage of combining pseudocontact shifts with relaxation dispersion is the increase in the amplitude of dispersion profiles. Lowly populated states are often involved in functional processes, such as enzyme catalysis, signaling, and protein/protein interactions. The presented results also unveil a critical problem with the lanthanide tag used to generate paramagnetic relaxation dispersion effects in proteins, namely that the motions of the tag can interfere severely with the observation of protein dynamics. The two-point attached CLaNP-5 lanthanide tag was linked to adenylate kinase. From the paramagnetic relaxation dispersion only motion of the tag is observed. The data can be described accurately by a two-state model in which the protein-attached tag undergoes a 23° tilting motion on a timescale of milliseconds. The work demonstrates the large potential of paramagnetic relaxation dispersion and the challenge to improve current tags to minimize relaxation dispersion from tag movements

  2. An initiation-promotion model of tumour prevalence from high-charge and energy radiations

    Cucinotta, F. A.; Wilson, J. W.

    1994-01-01

    A repair/misrepair kinetic model for multiple radiation-induced lesions (mutation inactivation) is coupled to a two-mutation model of initiation-promotion in tissue to provide a parametric description of tumour prevalence in the mouse Harderian gland from high-energy and charge radiations. Track-structure effects are considered using an action-cross section model. Dose-response curves are described for gamma rays and relativistic ions, and good agreement with experiment is found. The effects of nuclear fragmentation are also considered for high-energy proton and alpha-particle exposures. The model described provides a parametric description of age-dependent cancer induction for a wide range of radiation fields. Radiosensitivity parameters found in the model for an initiation mutation (sigma 0 = 7.6 x 10(-10) cm2 and D0 = 148.0 Gy) are somewhat different than previously observed for neoplastic transformation of C3H10T1/2 cell cultures (sigma 0 = 0.7 x 10(-10) cm2 and D0 = 117.0 Gy). We consider the two hypotheses that radiation acts solely as an initiator or as both initiator and promoter and make model calculations for fractionation exposures from gamma rays and relativistic Fe ions. For fractionated Fe exposures, an inverse-dose-rate effect is provided by a promotion hypothesis with an increase of 30% or more, dependent on the dose level and fractionation schedule, using a mutation rate for promotion similar to that of single-gene mutations.

  3. Dynamical investigation and parameter stability region analysis of a flywheel energy storage system in charging mode

    In this paper, the dynamic behavior analysis of the electromechanical coupling characteristics of a flywheel energy storage system (FESS) with a permanent magnet (PM) brushless direct-current (DC) motor (BLDCM) is studied. The Hopf bifurcation theory and nonlinear methods are used to investigate the generation process and mechanism of the coupled dynamic behavior for the average current controlled FESS in the charging mode. First, the universal nonlinear dynamic model of the FESS based on the BLDCM is derived. Then, for a 0.01 kWh/1.6 kW FESS platform in the Key Laboratory of the Smart Grid at Tianjin University, the phase trajectory of the FESS from a stable state towards chaos is presented using numerical and stroboscopic methods, and all dynamic behaviors of the system in this process are captured. The characteristics of the low-frequency oscillation and the mechanism of the Hopf bifurcation are investigated based on the Routh stability criterion and nonlinear dynamic theory. It is shown that the Hopf bifurcation is directly due to the loss of control over the inductor current, which is caused by the system control parameters exceeding certain ranges. This coupling nonlinear process of the FESS affects the stability of the motor running and the efficiency of energy transfer. In this paper, we investigate into the effects of control parameter change on the stability and the stability regions of these parameters based on the averaged-model approach. Furthermore, the effect of the quantization error in the digital control system is considered to modify the stability regions of the control parameters. Finally, these theoretical results are verified through platform experiments. (interdisciplinary physics and related areas of science and technology)

  4. Dynamical investigation and parameter stability region analysis of a flywheel energy storage system in charging mode

    Zhang, Wei-Ya; Li, Yong-Li; Chang, Xiao-Yong; Wang, Nan

    2013-09-01

    In this paper, the dynamic behavior analysis of the electromechanical coupling characteristics of a flywheel energy storage system (FESS) with a permanent magnet (PM) brushless direct-current (DC) motor (BLDCM) is studied. The Hopf bifurcation theory and nonlinear methods are used to investigate the generation process and mechanism of the coupled dynamic behavior for the average current controlled FESS in the charging mode. First, the universal nonlinear dynamic model of the FESS based on the BLDCM is derived. Then, for a 0.01 kWh/1.6 kW FESS platform in the Key Laboratory of the Smart Grid at Tianjin University, the phase trajectory of the FESS from a stable state towards chaos is presented using numerical and stroboscopic methods, and all dynamic behaviors of the system in this process are captured. The characteristics of the low-frequency oscillation and the mechanism of the Hopf bifurcation are investigated based on the Routh stability criterion and nonlinear dynamic theory. It is shown that the Hopf bifurcation is directly due to the loss of control over the inductor current, which is caused by the system control parameters exceeding certain ranges. This coupling nonlinear process of the FESS affects the stability of the motor running and the efficiency of energy transfer. In this paper, we investigate into the effects of control parameter change on the stability and the stability regions of these parameters based on the averaged-model approach. Furthermore, the effect of the quantization error in the digital control system is considered to modify the stability regions of the control parameters. Finally, these theoretical results are verified through platform experiments.

  5. Transverse Momentum Distributions of Charged Particles in Nuclear Collisions at RHIC Energies

    The paper reports on measurements of the transverse momentum distributions of produced particles from nuclear collisions at the highest center-of-mass energies provided by the Relativistic Heavy Ion Collider (RHIC). The transverse momentum spectra of charged hadrons produced in d + Au and Au + Au collisions at the top RHIC energy of 200 GeV in the nucleon-nucleon center-of-mass system are presented. For the Au + Au system, the measurements at the lower energy of 62.4 GeV are also reported. The analyzed data were collected by the PHOBOS experiment during several RHIC data-taking runs from 2001 to 2004. The main emphasis of this paper is the measurement of particle production at very low transverse momenta, a possibility uniquely available to the PHOBOS detector. A new non-standard method was developed to extract yields of (π+ + π-), (K+ + K-) and (p + p(bar)) at the lowest transverse momentum values accessible at RHIC. The results do not confirm the prediction of a significant enhancement in particle production at very low pT . The flattening of proton and antiproton pT spectra, consistent with the expectations of transverse expansion of the system, is clearly observed down to very low pT . In contrast to Au + Au collisions, such a flattening is not observed in yields of d + Au collisions at √sNN = 200 GeV. The scaling properties of mT spectra in Au + Au and d + Au collisions, as well as particle ratios, are discussed. Results obtained from the analysis of the transverse momentum distributions clearly show that the matter produced in nuclear collisions at RHIC energies is strongly coupled and undergoes a rapid transverse expansion. Comparison to the predictions of different models aiming to describe particle production in ultra-relativistic nuclear collisions is discussed. The characteristics of the system derived from this study of the transverse momentum distributions has provided a significant contribution to the RHIC discovery of a new state of matter, a

  6. CHARGE-TRANSFER AND ENERGY-TRANSFER IN THE PHOTO-INDUCED COPOLYMERIZATION OF 2-VINYLNAPHTHALENE WITH MALEIC ANHYDRIDE

    LI Tong; LUO Bin; LI Shanjun; CHU Guobei

    1990-01-01

    The initiation mechanism of the copolymerization of 2-vinylnaphthalene with maleic anhydride was studied under irradiation of 365 nm. The excited complex was formed from ( 1 ) the local excitation of 2-vinylnaphthalene followed by the charge-transfer interaction with maleic anhydride and ( 2 ) the excitation of the ground state charge-transfer complex, and then it collapsed to 1,4-tetramethylene biradical for initiation. A 1:1 alternating copolymer was formed in different monomer feeds. Addition of benzophenone could greatly enhance the rate of copolymerization through energy-transfer mechanism.

  7. Rapid heating tensile tests of hydrogen-charged high-energy-rate-forged 316L stainless steel

    Mosley, W.C.

    1989-05-19

    316L stainless steel is a candidate material for construction of equipment that will be exposed to tritium. Proper design of the equipment will require an understanding of how tritium and its decay product helium affect mechanical properties. This memorandum describes results of rapid heating tensile testing of hydrogen-charged specimens of high-energy-rate-forged (HERF) 316L stainless steel. These results provide a data base for comparison with uncharged and tritium-charged-and-aged specimens to distinguish the effects of hydrogen and helium. Details of the experimental equipment and procedures and results for uncharged specimens were reported previously. 3 refs., 10 figs.

  8. Squeezing out hydrated protons: low-frictional-energy triboelectric insulator charging on a microscopic scale

    Nikolaus Knorr

    2011-06-01

    Full Text Available Though triboelectric charging of insulators is common, neither its mechanism nor the nature of the charge is well known. Most research has focused on the integral amount of charge transferred between two materials upon contact, establishing, e.g., a triboelectric series. Here, the charge distribution of tracks on insulating polymer films rubbed by polymer-covered pointed swabs is investigated in high resolution by Kelvin probe force microscopy. Pronounced bipolar charging was observed for all nine rubbing combinations of three different polymers, with absolute surface potentials of up to several volts distributed in streaks along the rubbing direction and varying in polarity on μm-length scales perpendicular to the rubbing direction. Charge densities increased considerably for rubbing in higher relative humidity, for higher rubbing loads, and for more hydrophilic polymers. The ends of rubbed tracks had positively charged rims. Surface potential decay with time was strongly accelerated in increased humidity, particularly for polymers with high water permeability. Based on these observations, a mechanism is proposed of triboelectrification by extrusions of prevalently hydrated protons, stemming from adsorbed and dissociated water, along pressure gradients on the surface by the mechanical action of the swab. The validity of this mechanism is supported by explanations given recently in the literature for positive streaming currents of water at polymer surfaces and by reports of negative charging of insulators tapped by accelerated water droplets and of potential built up between the front and the back of a rubbing piece, observations already made in the 19th century. For more brittle polymers, strongly negatively charged microscopic abrasive particles were frequently observed on the rubbed tracks. The negative charge of those particles is presumably due in part to triboemission of electrons by polymer chain scission, forming radicals and negatively

  9. Swarm Intelligence-Based Smart Energy Allocation Strategy for Charging Stations of Plug-In Hybrid Electric Vehicles

    Imran Rahman

    2015-01-01

    Full Text Available Recent researches towards the use of green technologies to reduce pollution and higher penetration of renewable energy sources in the transportation sector have been gaining popularity. In this wake, extensive participation of plug-in hybrid electric vehicles (PHEVs requires adequate charging allocation strategy using a combination of smart grid systems and smart charging infrastructures. Daytime charging stations will be needed for daily usage of PHEVs due to the limited all-electric range. Intelligent energy management is an important issue which has already drawn much attention of researchers. Most of these works require formulation of mathematical models with extensive use of computational intelligence-based optimization techniques to solve many technical problems. In this paper, gravitational search algorithm (GSA has been applied and compared with another member of swarm family, particle swarm optimization (PSO, considering constraints such as energy price, remaining battery capacity, and remaining charging time. Simulation results obtained for maximizing the highly nonlinear objective function evaluate the performance of both techniques in terms of best fitness.

  10. Reduction and scientific analysis of data from the charge-energy-mass (CHEM) spectrometer on the AMPTE/CCE spacecraft

    Gloeckler, G.; Hamilton, D. C.; Ipavich, F. M.

    1987-01-01

    The Charge-Energy-Mass (CHEM) spectrometer instrument on the AMPTE/Charge Composition Explorer (CCE) spacecraft is designed to measure the mass and charge-state abundance of magnetospheric and magnetosheath ions between 0.3 and 315 keV/e, an energy range that includes the bulk of the ring current and the dynamically important portion of the plasma sheet population. Continuing research is being conducted using the AMPTE mission data set, and in particular, that of the CHEM spectrometer which has operated flawlessly since launch and still provides excellent quality data. The requirted routine data processing and reduction, and software develpment continues to be performed. Scientific analysis of composition data in a number of magnetospheric regions including the ring current region, near-earth plasma sheet and subsolar magnetosheath continues to be undertaken. Correlative studies using data from the sister instrument SULEICA, which determines the mass and charge states of ions in the energy range of approximately 10 to 250 keV/e on the IRM, as well as other data from the CCE and IRM spacecraft, particularly in the upstream region and plasma sheet have also been undertaken.

  11. Beam-Energy and System-Size Dependence of Dynamical Net Charge Fluctuations

    Abelev, B I; Ahammed, Z; Anderson, B D; Arkhipkin, D; Averichev, G S; Bai, Y; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Baumgart, S; Beavis, D R; Bellwied, R; Benedosso, F; Betts, R R; Bhardwaj, S; Bhasin, A; Bhati, A K; Bichsel, H; Bielcik, J; Bielcikova, J; Biritz, B; Bland, L C; Bombara, M; Bonner, B E; Botje, M; Bouchet, J; Braidot, E; Brandin, A V; Bültmann, S; Burton, T P; Bystersky, M; Cai, X Z; Caines, H; Sánchez, M Calderón de la Barca; Callner, J; Catu, O; Cebra, D; Cendejas, R; Cervantes, M C; Chajecki, Z; Chaloupka, P; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, J Y; Cheng, J; Cherney, M; Chikanian, A; Choi, K E; Christie, W; Chung, S U; Clarke, R F; Codrington, M J M; Coffin, J P; Cormier, T M; Cosentino, M R; Cramer, J G; Crawford, H J; Das, D; Dash, S; Daugherity, M; Dedovich, T G; DePhillips, M; Derevshchikov, A A; de Souza, R Derradi; Didenko, L; Djawotho, P; Dogra, S M; Dong, X; Drachenberg, J L; Draper, J E; Du, F; Dunlop, J C; Mazumdar, M R Dutta; Edwards, W R; Efimov, L G; Elhalhuli, E; Elnimr, M; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Estienne, M; Eun, L; Fachini, P; Fatemi, R; Fedorisin, J; Feng, A; Filip, P; Finch, E; Fine, V; Fisyak, Yu; Gagliardi, C A; Gaillard, L; Gangadharan, D R; Ganti, M S; García-Solis, E; Ghazikhanian, V; Ghosh, P; Gorbunov, Y N; Gordon, A; Grebenyuk, O; Grosnick, D; Grube, B; Guertin, S M; Guimaraes, K S F F; Sen-Gupta, A; Gupta, N; Guryn, W; Haag, B; Hallman, T J; Hamed, A; Harris, J W; He, W; Heinz, M; Heppelmann, S; Hippolyte, B; Hirsch, A; Hoffman, A M; Hoffmann, G W; Hofman, D J; Hollis, R S; Huang, H Z; Humanic, T J; Igo, G; Iordanova, A; Jacobs, P; Jacobs, W W; Jakl, P; Jin, F; Jones, P G; Judd, E G; Kabana, S; Kajimoto, K; Kang, K; Kapitan, J; Kaplan, M; Keane, D; Kechechyan, A; Kettler, D; Khodyrev, V Yu; Kiryluk, J; Kisiel, A; Klein, S R; Knospe, A G; Kocoloski, A; Koetke, D D; Kopytine, M; Kotchenda, L; Kouchpil, V; Kravtsov, P; Kravtsov, V I; Krüger, K; Kuhn, C; Kumar, L; Kurnadi, P; Lamont, M A C; Landgraf, J M; LaPointe, S; Lauret, J; Lebedev, A; Lednicky, R; Lee, C-H; Le Vine, M J; Li, C; Li, Y; Lin, G; Lin, X; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, J; Liu, L; Ljubicic, T; Llope, W J; Longacre, R S; Love, W A; Lu, Y; Ludlam, T; Lynn, D; Ma, G L; Ma, Y G; Mahapatra, D P; Majka, R; Mangotra, L K; Manweiler, R; Margetis, S; Markert, C; Matis, H S; Matulenko, Yu A; McShane, T S; Meschanin, A; Millane, J; Miller, M L; Minaev, N G; Mioduszewski, S; Mischke, A; Mitchell, J; Mohanty, B; Morozov, D A; Munhoz, M G; Nandi, B K; Nattrass, C; Nayak, T K; Nelson, J M; Nepali, C; Netrakanti, P K; Ng, M J; Nogach, L V; Nurushev, S B; Odyniec, Grazyna Janina; Ogawa, A; Okada, H; Okorokov, V; Olson, D; Pachr, M; Pal, S K; Panebratsev, Yu A; Pawlak, T; Peitzmann, T; Perevozchikov, V; Perkins, C; Peryt, W; Phatak, S C; Planinic, M; Pluta, J; Poljak, N; Porile, N; Poskanzer, A M; Potukuchi, B V K S; Prindle, D; Pruneau, C; Pruthi, N K; Putschke, J; Qattan, I A; Raniwala, R; Raniwala, S; Ray, R L; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Romero, J L; Rose, A; Roy, C; Ruan, L; Russcher, M J; Rykov, V; Sahoo, R; Sakrejda, I; Sakuma, T; Salur, S; Sandweiss, J; Sarsour, M; Schambach, J; Scharenberg, R P; Schmitz, N; Seger, J; Selyuzhenkov, I; Seyboth, P; Shabetai, A; Shahaliev, E; Shao, M; Sharma, M; Shi, S S; Shi, X-H; Sichtermann, E P; Simon, F; Singaraju, R N; Skoby, M J; Smirnov, N; Snellings, R; Sørensen, P; Sowinski, J; Spinka, H M; Srivastava, B; Stadnik, A; Stanislaus, T D S; Staszak, D; Strikhanov, M; Stringfellow, B; Suaide, A A P; Suarez, M C; Subba, N L; Sumbera, M; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Symons, T J M; de Toledo, A Szanto; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thein, D; Thomas, J H; Tian, J; Timmins, A R; Timoshenko, S; Tokarev, M; Trainor, T A; Tram, V N; Trattner, A L; Trentalange, S; Tribble, R E; Tsai, O D; Ulery, J; Ullrich, T; Underwood, D G; Van Buren, G; Van der Kolk, N; Van Leeuwen, M; Molen, A M Vander; Varma, R; Vasconcelos, G M S; Vasilevski, I M; Vasilev, A N; Videbaek, F; Vigdor, S E; Viyogi, Y P; Vokal, S; Voloshin, S A; Wada, M; Waggoner, W T; Wang, F; Wang, G; Wang, J S; Wang, Q; Wang, X; Wang, X L; Wang, Y; Webb, J C; Westfall, G D; Whitten, C; Wieman, H; Wissink, S W; Witt, R; Wu, J; Wu, Y; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yepes, P; Yoo, I-K; Yue, Q; Zawisza, M; Zbroszczyk, H; Zhan, W; Zhang, H; Zhang, S; Zhang, W M; Zhang, Y; Zhang, Z P; Zhao, Y; Zhong, C; Zhou, J; Zoulkarneev, R; Zoulkarneeva, Y; Zuo, J X

    2008-01-01

    We present measurements of net charge fluctuations in $Au + Au$ collisions at $\\sqrt{s_{NN}} = $ 19.6, 62.4, 130, and 200 GeV, $Cu + Cu$ collisions at $\\sqrt{s_{NN}} = $ 62.4, 200 GeV, and $p + p$ collisions at $\\sqrt{s} = $ 200 GeV using the dynamical net charge fluctuations measure $\

  12. Beam energy dependence of moments of the net-charge multiplicity distributions in Au+Au collisions at RHIC

    ,

    2014-01-01

    We report the first measurements of the moments -mean ($M$), variance ($\\sigma^{2}$), skewness ($S$) and kurtosis ($\\kappa$) -of the net-charge multiplicity distributions at mid-rapidity in Au+Au collisions at seven energies, ranging from $\\sqrt {{s_{\\rm NN}}}$=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net-charge, which are expected to diverge at the QCD critical point. We compare the products of the moments, $\\sigma^{2}/M$, $S\\sigma$ and $\\kappa\\sigma^{2}$ with the expectations from Poisson and negative binomial distributions (NBD). The $S\\sigma$ values deviate from Poisson and are close to NBD baseline, while the $\\kappa\\sigma^{2}$ values tend to lie between the two. Within the present uncertainties, our data do not show clear evidence of non-monotonic behavior as a function of collision energy.

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

    Regnier, D; Schunck, N; Verriere, M

    2016-01-01

    Accurate knowledge of fission fragment yields is an essential ingredient of numerous applications ranging from the formation of elements in the r-process to fuel cycle optimization for nuclear energy. The need for a predictive theory applicable where no data is available is an incentive to develop a fully microscopic approach to fission dynamics. In this work, we calculate the pre-neutron emission charge and mass distributions of the fission fragments formed in the neutron-induced fission of 239Pu using a microscopic method based on nuclear energy density functional (EDF) method, where large amplitude collective motion is treated adiabatically using the time dependent generator coordinate method (TDGCM) under the Gaussian overlap approximation (GOA). Fission fragment distributions are extracted from the flux of the collective wave packet through the scission line. We find that the main characteristics of the fission charge and mass distributions can be well reproduced by existing energy functionals even in tw...

  14. Measurement of charge composition of electron flows with an energy above hundreds MeV in inner radiaion belt

    A detector for studying the charge composition of a high-energy electron component of an internal radiation belt when measuring the precipitation of charged particles in the region of Brazil magnetic anomaly is suggested. The detector is a telescope consisting of two semiconductors and CsI crystal housed into a protection detector in the form of a cup made of plastic scintillator. An absorber of plastic scintillator is placed between semiconductive detections. The detector may record positrons with energy up to 5 MeV in the composition of precipitating particles from the belt in definite detector signal combination and specific energy release 511 keV in CsI crystal. 16 refs.; 3 figs

  15. A power management system for energy harvesting and wireless sensor networks application based on a novel charge pump circuit

    Aloulou, R.; De Peslouan, P.-O. Lucas; Mnif, H.; Alicalapa, F.; Luk, J. D. Lan Sun; Loulou, M.

    2016-05-01

    Energy Harvesting circuits are developed as an alternative solution to supply energy to autonomous sensor nodes in Wireless Sensor Networks. In this context, this paper presents a micro-power management system for multi energy sources based on a novel design of charge pump circuit to allow the total autonomy of self-powered sensors. This work proposes a low-voltage and high performance charge pump (CP) suitable for implementation in standard complementary metal oxide semiconductor (CMOS) technologies. The CP design was implemented using Cadence Virtuoso with AMS 0.35μm CMOS technology parameters. Its active area is 0.112 mm2. Consistent results were obtained between the measured findings of the chip testing and the simulation results. The circuit can operate with an 800 mV supply and generate a boosted output voltage of 2.835 V with 1 MHz as frequency.

  16. Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy Storage in DC Microgrids

    Li, Chendan; Dragicevic, Tomislav; Aldana, Nelson Leonardo Diaz;

    2014-01-01

    State-of-Charge balance. In this paper, a new droop method based on voltage scheduling for State-of-Charge balance is proposed to keep the SoC balance for the energy storage units. The proposed method has the advantage of avoiding the stability problem existed in traditional methods based on droop gain...... scheduling. Simulation experiment is taken in Matlab on a DC microgrid with two distributed energy storage units. The simulation results show that the proposed method has successfully achieved SoC balance during the load changes while maintaining the DC bus voltage within the allowable range.......Due to higher power quality, lower conversion loss, and more DC loads, there has been an increasing awareness on DC microgrid. Previous emphasis has been on equal power sharing among different units in the DC microgrid, while overlooking the coordination of the energy storage units to maintain the...

  17. Equilibrium fluid-crystal interfacial free energy of bcc-crystallizing aqueous suspensions of polydisperse charged spheres

    Palberg, Thomas; Wette, Patrick; Herlach, Dieter M.

    2016-02-01

    The interfacial free energy is a central quantity in crystallization from the metastable melt. In suspensions of charged colloidal spheres, nucleation and growth kinetics can be accurately measured from optical experiments. In previous work, from these data effective nonequilibrium values for the interfacial free energy between the emerging bcc nuclei and the adjacent melt in dependence on the chemical potential difference between melt phase and crystal phase were derived using classical nucleation theory (CNT). A strictly linear increase of the interfacial free energy was observed as a function of increased metastability. Here, we further analyze these data for five aqueous suspensions of charged spheres and one binary mixture. We utilize a simple extrapolation scheme and interpret our findings in view of Turnbull's empirical rule. This enables us to present the first systematic experimental estimates for a reduced interfacial free energy, σ0 ,b c c, between the bcc-crystal phase and the coexisting equilibrium fluid. Values obtained for σ0 ,b c c are on the order of a few kBT . Their values are not correlated to any of the electrostatic interaction parameters but rather show a systematic decrease with increasing size polydispersity and a lower value for the mixture as compared to the pure components. At the same time, σ0 also shows an approximately linear correlation to the entropy of freezing. The equilibrium interfacial free energy of strictly monodisperse charged spheres may therefore be still greater.

  18. Reducing greenhouse gas emissions by inducing energy conservation and distributed generation from elimination of electric utility customer charges

    This paper quantifies the increased greenhouse gas emissions and negative effect on energy conservation (or 'efficiency penalty') due to electric rate structures that employ an unavoidable customer charge. First, the extent of customer charges was determined from a nationwide survey of US electric tariffs. To eliminate the customer charge nationally while maintaining a fixed sum for electric companies for a given amount of electricity, an increase of 7.12% in the residential electrical rate was found to be necessary. If enacted, this increase in the electric rate would result in a 6.4% reduction in overall electricity consumption, conserving 73 billion kW h, eliminating 44.3 million metric tons of carbon dioxide, and saving the entire US residential sector over $8 billion per year. As shown here, these reductions would come from increased avoidable costs, thus leveraging an increased rate of return on investments in energy efficiency, energy conservation behavior, distributed energy generation, and fuel choices. Finally, limitations of this study and analysis are discussed and conclusions are drawn for proposed energy policy changes

  19. Measurements of the charge exchange and dissociation cross-sections of the H2+ ion in a wide energy range

    The dissociation, ionisation, and charge exchange cross-sections of molecular hydrogen ions H2+ passing through various gases, have been measured as a function of the energy of the ions. The energy range studied was from 25 to 250 keV. The reaction products, analysed by a magnetic field according to their e/m ratio, are collected on scintillation detectors. Two methods have made it possible to separate the various reactions leading to the formation of particles having the same e/m ratio. The first separates the particles according to their energy, the other selects those arriving simultaneously on two different detectors. The results show a large variation in the charge exchange cross-section with the energy of the H2+ ions. The variations in the dissociation and ionisation cross-sections are less pronounced. For a given energy, the values of the cross-sections increase with the atomic weight of the target particles. These measurements have been extended to the case of H2+ ions passing through a target of charged particles. Preliminary results show an increase in the cross-sections as compared to the preceding case. Finally the scattering of the reaction products has been studied; this scattering is due to the fact that the molecules formed during a reaction are in an unstable state and the nuclei or atoms diverge from each other. (author)

  20. Search for charged scalars in e+e- annihilation up to 64 GeV CM energy

    A search for the production of charged scalars has been carried out in e+e- annihilation at center of mass energies up to 64 GeV with 61.1 pb-1 of integrated luminosity using the VENUS detector at TRISTAN. The assumptions concerning the production and decay of hypothetical charged scalars are minimal; they are expected to be singly charged and decay into a pair of fermions. No positive evidence for their production has been found in a study of all combinations of the anti lν(lanti ν) and Uanti D(anti UD) decay channels. We have excluded the mass region of 8.0-20.0 GeV/c2 regardless of the decay mode. (orig.)

  1. Search for charged scalars in e sup + e sup - annihilation up to 64 GeV CM energy

    Yuzuki, T.; Haba, J.; Kanda, N.; Nagashima, Y.; Sugimoto, S.; Suzuki, A.; Takaki, H.; Takita, M. (Dept. of Physics, Osaka Univ., Toyonaka (Japan)); Abe, K. (Dept. of Physics, Tohoku Univ., Sendai (Japan)); Amako, K.; Arai, Y.; Fukawa, M.; Fukushima, Y.; Ishihara, N.; Kamitani, T.; Kanematsu, N.; Kanzaki, J.; Kondo, T.; Korhonen, T.T.; MacNaughton, J.; Matsui, T.; Odaka, S.; Ogawa, K.; Ohama, T.; Sakamoto, H.; Sakuda, M.; Shirai, J.; Sumiyoshi, T.; Takasaki, F.; Tsuboyama, T.; Uehara, S.; Unno, Y.; Watase, Y.; Yamada, Y. (KEK, National Lab. for High Energy Physics, Ibaraki (Japan)); Asano, Y.; Mori, S.; Shirakata, M.; Takada, Y.; Yonezawa, Y. (Inst. of Applied Physics, Univ. of Tsukuba, Ibaraki (Japan)); Chiba, M.; Fukui, T.; Hinode, F.; Hirose, T.; Minami, M.; Narita, Y.; Oyama, T.; Utsumi, M.; Watanabe, T.; Yabuki, F. (Dept. of Physics, Tokyo Metropolitan Univ. (Japan)); Chiba, Y.; Ohsugi, T.; Taketani, A.; Terunuma, N. (Dept. of Physics, Hiroshima Univ. (Japan)); Daigo, M. (Wak

    1991-09-12

    A search for the production of charged scalars has been carried out in e{sup +}e{sup -} annihilation at center of mass energies up to 64 GeV with 61.1 pb{sup -1} of integrated luminosity using the VENUS detector at TRISTAN. The assumptions concerning the production and decay of hypothetical charged scalars are minimal; they are expected to be singly charged and decay into a pair of fermions. No positive evidence for their production has been found in a study of all combinations of the anti l{nu}(lanti {nu}) and Uanti D(anti UD) decay channels. We have excluded the mass region of 8.0-20.0 GeV/c{sup 2} regardless of the decay mode. (orig.).

  2. Fusion Energy Advisory Committee: Advice and recommendations to the Department of Energy in partial response to the Charge Letter of September 24, 1991: Part D

    This document is a compilation of the written records that relate to the Fusion Energy Advisory Committee's deliberations with regard to the Letter of Charge received from the Director of Energy Research, dated September 24, 1991. During its fourth meeting, held in May 1992, FEAC provided a detailed response to that part of the charge that requested review of the potential effectiveness, and hence the advisability, of implementing a more diverse US fusion program. In particular, it responded to the paragraph: ''By May 1992, 1 would like to have your recommendations on a US concept improvement program, including relative priorities and taking into account ongoing and planned work abroad.'' In order to respond to this charge in a timely manner, FEAC established a working group, designated ''Panel number-sign 3'', which reviewed the US and international fusion programs in detail and prepared background material, included in this report as Appendix 1, to help FEAC in its deliberations

  3. Impact of plug-in hybrid electric vehicles charging demand on the optimal energy management of renewable micro-grids

    This paper suggests a new stochastic expert framework to investigate the charging effect of plug-in hybrid electric vehicles (PHEVs) on the optimal operation and management of micro-grids (MGs). In this way, a useful method based on smart charging approach is proposed to consider the charging demand of PHEVs in both residential location and public charging stations. The analysis is simulated for 24 h considering the uncertainties associated with the forecast error in the charging demand of PHEVs, hourly load consumption, hourly energy price and Renewable Energy Sources (RESs) output power. In order to see the effect of storage devices on the operation of the MG, NiMH-Battery is also incorporated in the MG. According to the high complexity of the problem, a new optimization method called θ-krill herd (θ-KH) algorithm is proposed which uses the phase angle vectors to update the velocity/position of krill animals with faster and more stable convergence. In addition, a new modification method is proposed to improve the search ability of the algorithm, effectively. The suggested problem is examined on an MG including different RESs such as photovoltaic (PV), fuel cells (FCs), wind turbine (WT), micro turbine (MT) and battery as the storage device. - Highlights: • Introducing an expert stochastic framework for optimal operation and management of MGs including PHEVs. • Introducing a new artificial optimization algorithm based on KH evolutionary technique. • Introducing a new version of KH algorithm called θ-KH for the optimization applications. • Modeling the uncertainty of forecast error in Wind turbine, Photovoltaics, market price, load data, PHEVs electric charging demand in an intelligent framework

  4. Experimental study of interactions of highly charged ions with atoms at keV energies: Progress report for period May 15, 1985-February 15, 1987

    Interest in interactions of low energy highly charged ions with electrons, atoms or ions is due to their importance to controlled thermonuclear fusion research and the interesting nature of the fundamental processes involved. Studies of such interactions have long been hampered by a lack of suitable ions sources. A superconducting solenoid, cryogenic Electron Beam Ion Source, CEBIS, has been constructed at Cornell University to produce low energy very highly charged ions. At present, using a pulsed 0.5A,8.5 keV electron beam, the source is capable of producing highly charged ions of C,N,O, including bare nuclei, and ions of Ar up to charge state 11 + in 1 millisecond of confinement time. The source is being used in experiments to investigate charge transfer and accompanying processes in low energy, highly charged ion-atom collisions

  5. U.S. Department of Energy's EV Everywhere Workplace Charging Challenge, Mid-Program Review: Employees Plug In

    2015-12-01

    This Program Review takes an unprecedented look at the state of workplace charging in the United States -- a report made possible by U.S. Department of Energy leadership and valuable support from our partners as they share their progress in developing robust workplace charging programs. Through the Workplace Charging Challenge, more than 250 participants are accelerating the development the nation's worksite PEV charging infrastructure and are supporting cleaner, more convenient transportation options within their communities. Challenge partners are currently providing access to PEV charging stations at more than 440 worksites across the country and are influencing countless other organizations to do the same.

  6. Measurement of the atmospheric muon charge ratio at TeV energies with the MINOS detector

    Adamson, P.; Andreopoulos, C.; Arms, K. E.; Armstrong, R.; Auty, D. J.; Avvakumov, S.; Ayres, D. S.; Baller, B.; Barish, B.; Barnes, JR; Falk Harris, E; Harris, P.G.; Hartnell, J.; Symes, P. A.; et al, ...

    2007-01-01

    The 5.4 kton MINOS far detector has been taking charge-separated cosmic ray muon data since the beginning of August, 2003 at a depth of 2070 meters-water-equivalent in the Soudan Underground Laboratory, Minnesota, USA. The data with both forward and reversed magnetic field running configurations were combined to minimize systematic errors in the determination of the underground muon charge ratio. When averaged, two independent analyses find the charge ratio underground to be 1.374 +/- 0.004 (...

  7. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. Rotarod test: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. Open field test: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. Morris water maze: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the central nervous system (CNS). ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process. (author)

  8. Low energy highly charged ion beam facility at Inter University Accelerator Centre: Measurement of the plasma potential and ion energy distributions

    A deceleration lens coupled to one of the beam lines of the electron cyclotron resonance based low energy beam facility at Inter University Accelerator Centre is reported. This system is capable of delivering low energy (2.5 eV/q–1 keV/q) highly charged ion beams. The presence of plasma potential hinders the measurements of low energies (<50 eV), therefore, plasma potential measurements have been undertaken using a retarding plate analyzer in unison with the deceleration assembly. The distributions of the ion energies have been obtained and the effect of different source parameters on these distributions is studied

  9. A universal self-charging system driven by random biomechanical energy for sustainable operation of mobile electronics

    Niu, Simiao; Wang, Xiaofeng; Yi, Fang; Zhou, Yu Sheng; Wang, Zhong Lin

    2015-12-01

    Human biomechanical energy is characterized by fluctuating amplitudes and variable low frequency, and an effective utilization of such energy cannot be achieved by classical energy-harvesting technologies. Here we report a high-efficient self-charging power system for sustainable operation of mobile electronics exploiting exclusively human biomechanical energy, which consists of a high-output triboelectric nanogenerator, a power management circuit to convert the random a.c. energy to d.c. electricity at 60% efficiency, and an energy storage device. With palm tapping as the only energy source, this power unit provides a continuous d.c. electricity of 1.044 mW (7.34 W m-3) in a regulated and managed manner. This self-charging unit can be universally applied as a standard `infinite-lifetime' power source for continuously driving numerous conventional electronics, such as thermometers, electrocardiograph system, pedometers, wearable watches, scientific calculators and wireless radio-frequency communication system, which indicates the immediate and broad applications in personal sensor systems and internet of things.

  10. Structural characterization of Burkholderia pseudomallei adenylate kinase (Adk): Profound asymmetry in the crystal structure of the 'open' state

    Buchko, G.W.; Robinson, H.; Abendroth, J.; Staker, B. L.; Myler, P. J.

    2010-04-16

    In all organisms adenylate kinases (Adks) play a vital role in cellular energy metabolism and nucleic acid synthesis. Due to differences in catalytic properties between the Adks found in prokaryotes and in the cytoplasm of eukaryotes, there is interest in targeting this enzyme for new drug therapies against infectious bacterial agents. Here we report the 2.1 {angstrom} resolution crystal structure for the 220-residue Adk from Burkholderia pseudomallei (BpAdk), the etiological agent responsible for the infectious disease melioidosis. The general structure of apo BpAdk is similar to other Adk structures, composed of a CORE subdomain with peripheral ATP-binding (ATP{sub bd}) and LID subdomains. The two molecules in the asymmetric unit have significantly different conformations, with a backbone RMSD of 1.46 {angstrom}. These two BpAdk conformations may represent 'open' Adk sub-states along the preferential pathway to the 'closed' substrate-bound state.

  11. An Accurate and Linear Scaling Method to Calculate Charge-Transfer Excitation Energies and Diabatic Couplings

    Pavanello, Michele; Visscher, Lucas; Neugebauer, Johannes

    2012-01-01

    Quantum--Mechanical methods that are both computationally fast and accurate are not yet available for electronic excitations having charge transfer character. In this work, we present a significant step forward towards this goal for those charge transfer excitations that take place between non-covalently bound molecules. In particular, we present a method that scales linearly with the number of non-covalently bound molecules in the system and is based on a two-pronged approach: The molecular electronic structure of broken-symmetry charge-localized states is obtained with the Frozen Density Embedding formulation of subsystem Density-Functional Theory; subsequently, in a post-SCF calculation, the full-electron Hamiltonian and overlap matrix elements among the charge-localized states are evaluated with an algorithm which takes full advantage of the subsystem DFT density partitioning technique. The method is benchmarked against Coupled-Cluster calculations and achieves chemical accuracy for the systems considered...

  12. Ultrafast energy and charge transfer in D2O/Ru(0001)

    Thin D2O layers on a Ru(0001) surface experiencing energy transfer from the photoexcited metal and charge confinement after UV illumination were studied with surface-sensitive optical techniques and in a time-resolved manner to gain a microscopic understanding of the fundamental processes within this system. The intrinsically interface-sensitive sum frequency generation (SFG) vibrational spectroscopy is employed to investigate the surface structure of an ice film grown on the Ru(0001) substrate with different thickness and thus with different interaction strength with the metal. The vibrational signatures of thicker ice samples show characteristic differences between the surfaces of amorphous and crystalline ice, but the structure of the wetting layer is significantly influenced by the metal and distinctly different from that of ice, which leads to the pronounced hydrophobic properties of the first water adlayer. The number of hydrogen bonds between this wetting layer and further multilayers is shown to be considerably limited, which most probably gives rise to the Stranski-Krastanov growth mechanism. In the present work, the reason for the stabilization is consistently explained. After an electron is excited from the metal into the (D2O) ice layer by an intense, ultrashort UV (4.66 eV) laser pulse and stabilized at its surface, the SFG vibrational spectrum in the OD stretch region is changed dramatically. Electron injection resonantly enhances the SFG signal up to a factor of 103, particularly in the frequency range of vibrations involved in hydrogen bonding. The signal from the ice surface is simultaneously overwhelmed by the contribution from the bulk. The observed changes do not spontaneously reverse back to the original state on a timescale of several hours and strongly depend on the D2O structure, since no change in the sum-frequency spectra of thin amorphous ice layers can be observed under otherwise identical conditions. The screening occurs on a timescale

  13. X-Ray Resonant Photoexcitation: Linewidths and Energies of Kα Transitions in Highly Charged Fe Ions

    Rudolph, J; Bernitt, S; Epp, S.; Steinbrügge, R.; Beilmann, C.; Brown, G.; Eberle, S.; A. Graf; Harman, Z.; Hell, N.; Leutenegger, M.; Müller, A.; Schlage, K.; Wille, H; Yavas, H.

    2013-01-01

    Photoabsorption by and fluorescence of the K{\\alpha} transitions in highly charged iron ions are essential mechanisms for X-ray radiation transfer in astrophysical environments. We study photoabsorption due to the main K{\\alpha} transitions in highly charged iron ions from heliumlike to fluorinelike (Fe 24+...17+) using monochromatic X-rays around 6.6 keV at the PETRA III synchrotron photon source. Natural linewidths were determined with hitherto unattained accuracy. The observed transitions ...

  14. Testing Partonic Charge Symmetry at a High-Energy Electron Collider

    Hobbs, T J; Murdock, D P; Thomas, A W

    2011-01-01

    We examine the possibility that one could measure partonic charge symmetry violation (CSV) by comparing neutrino or antineutrino production through charged-current reactions induced by electrons or positrons at a possible electron collider at the LHC. We calculate the magnitude of CSV that might be expected at such a facility. We show that this is likely to be a several percent effect, substantially larger than the typical CSV effects expected for partonic reactions.

  15. Impact of Fast Charging on Life of EV Batteries; NREL (National Renewable Energy Laboratory)

    Neubauer, Jeremy; Wood, Eric; Burton, Evan; Smith, Kandler; Pesaran, Ahmad

    2015-05-03

    Installation of fast charging infrastructure is considered by many as one of potential solutions to increase the utility and range of electric vehicles (EVs). This is expected to reduce the range anxiety of drivers of EVs and thus increase their market penetration. Level 1 and 2 charging in homes and workplaces is expected to contribute to the majority of miles driven by EVs. However, a small percentage of urban driving and most of inter-city driving could be only achieved by a fast-charging network. DC fast charging at 50 kW, 100 kW, 120 kW compared to level 1 (3.3 kW) and level 2 (6.6 kW) results in high-current charging that can adversely impact the life of the battery. In the last couple of years, we have investigated the impact of higher current rates in batteries and potential of higher temperatures and thus lower service life. Using mathematical models, we investigated the temperature increase of batteries due to higher heat generation during fast charge and have found that this could lead to higher temperatures. We compared our models with data from other national laboratories both for fine-tuning and calibration. We found that the incremental temperature rise of batteries during 1C to 3C fast charging may reduce the practical life of the batteries by less than 10% over 10 to 15 years of vehicle ownership. We also found that thermal management of batteries is needed for fast charging to prevent high temperature excursions leading to unsafe conditions.

  16. Final Technical Report for the Energy Frontier Research Center Understanding Charge Separation and Transfer at Interfaces in Energy Materials (EFRC:CST)

    Vanden Bout, David A. [Univ. of Texas, Austin, TX (United States)

    2015-09-14

    Our EFRC was founded with the vision of creating a broadly collaborative and synergistic program that would lead to major breakthroughs in the molecular-level understanding of the critical interfacial charge separation and charge transfer (CST) processes that underpin the function of candidate materials for organic photovoltaic (OPV) and electrical-energy-storage (EES) applications. Research in these energy contexts shares an imposing challenge: How can we understand charge separation and transfer mechanisms in the presence of immense materials complexity that spans multiple length scales? To address this challenge, our 50-member Center undertook a total of 28 coordinated research projects aimed at unraveling the CST mechanisms that occur at interfaces in these nanostructured materials. This rigorous multi-year study of CST interfaces has greatly illuminated our understanding of early-timescale processes (e.g., exciton generation and dissociation dynamics at OPV heterojunctions; control of Li+-ion charging kinetics by surface chemistry) occurring in the immediate vicinity of interfaces. Program outcomes included: training of 72 graduate student and postdoctoral energy researchers at 5 institutions and spanning 7 academic disciplines in science and engineering; publication of 94 peer-reviewed journal articles; and dissemination of research outcomes via 340 conference, poster and other presentations. Major scientific outcomes included: implementation of a hierarchical strategy for understanding the electronic communication mechanisms and ultimate fate of charge carriers in bulk heterojunction OPV materials; systematic investigation of ion-coupled electron transfer processes in model Li-ion battery electrode/electrolyte systems; and the development and implementation of 14 unique technologies and instrumentation capabilities to aid in probing sub-ensemble charge separation and transfer mechanisms.

  17. Comparison of the in vivo and in vitro activities of adenylate cyclase from Mycobacterium tuberculosis H37Ra(NCTC 7417)

    The incorporation of [14C] adenine into the adenosine 3', 5'-monophosphate (cyclic AMP) fraction by whole cells of Mycobacterium tuberculosis was taken as a measure of the in vivo activity of adenylate cyclase. The in vivo activity of adenylate cyclase was significantly inhibited by glucose, thus suggesting that the low level of cyclic AMP in the presence of glucose is due to the inhibited synthesis of cyclic AMP. In vitro activity of adenylate cyclase had optimum pH of 8.5 and Km of 1.33 mM for ATP. Glucose and other sugars did not show significant inhibition of in vitro activity. The results suggest that the adenylate cyclase activity becomes less sensitive to glucose when the bacterial cells are disrupted, an analogy with eukaryotic adenylate cyclase which loses sensitivity to hormones when the cells are disrupted. (auth.)

  18. Space Charge Correction on Emittance Measurement of Low Energy Electron Beams

    Treado, Colleen J.; /Massachusetts U., Amherst

    2012-09-07

    The goal of any particle accelerator is to optimize the transport of a charged particle beam along a set path by confining the beam to a small region close to the design trajectory and directing it accurately along the beamline. To do so in the simplest fashion, accelerators use a system of magnets that exert approximately linear electromagnetic forces on the charged beam. These electromagnets bend the beam along the desired path, in the case of bending magnets, and constrain the beam to the desired area through alternating focusing and defocusing effects, in the case of quadrupole magnets. We can model the transport of such a beam through transfer matrices representing the actions of the various beamline elements. However, space charge effects, produced from self electric fields within the beam, defocus the beam and must be accounted for in the calculation of beam emittance. We present below the preliminary results of a MATLAB code built to model the transport of a charged particle beam through an accelerator and measure the emittance under the influence of space charge effects. We demonstrate the method of correctly calculating the emittance of a beam under space charge effects using a least square fit to determine the initial properties of the beam given the beam size measured at a specific point after transport.

  19. The east-west effect of the muon charge ratio at energies relevant to the atmospheric neutrino anomaly

    The measurements of the muon charge ratio representing the ratio of positive to negative atmospheric muons are performed using a small compact device, WILLI, by detecting the life time of the muons in different materials. Avoiding the difficulties of measurements with magnetic spectrometers, this method gives precise results on muon charge ratio especially in the low energy range relevant for the atmospheric neutrino anomaly. In the present configuration the detector is constructed as a rotatable device which permits measurements on different azimuthal directions. The preliminary results for the energy of incident muon in the range of 0.3-0.5 GeV/c, at mean zenith angle of 35 angle, evidence the east-west effect similarly found in neutrino measurements. (authors)

  20. [Results of measuring the charge and energy spectra of heavy nuclei on board the artificial Earth satellite Kosmos-936].

    Dashin, S A; Marennyĭ, A M; Gertsen, G P

    1982-01-01

    The measurements were performed using a package of dielectric track detectors mounted behind the shield of 60-80 kg.m-2 thick. The charge of nuclei was determined from the complete track length. As a result, 1915 tracks of nuclei with Z greater than or equal to 6 in the energy range 100-450 MeV/nuclon were detected and identified. The differential charge spectrum of nuclei with 6 less than or equal to Z less than or equal to 28 and the energy spectrum of nuclei of the iron group were built. For iron nuclei the following ration of isotope groups was obtained: (Fe52 + Fe53 + Fe54): (Fe55 + Fe56 + Fe57) : (Fe58 + Fe59 + Fe60) = (0.30 +/- 0.08) = (0.49 +/- 0.10) : (0.21 +/- 0.05). PMID:7098416

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

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

    2016-01-01

    Accurate knowledge of fission fragment yields is an essential ingredient of numerous applications ranging from the formation of elements in the r-process to fuel cycle optimization for nuclear energy. The need for a predictive theory applicable where no data is available is an incentive to develop a fully microscopic approach to fission dynamics. In this work, we calculate the pre-neutron emission charge and mass distributions of the fission fragments formed in the neutron-induced fission of ...

  2. Energy-charge correlation in the π+π-π0 decay of K L and of tagged neutral kaons

    Buccella, F.; Pisanti, O.; Sannino, F.

    1995-03-01

    We relate the asymmetries in the charged pions energy in the decay into π+π-π0 of K L and of the tagged neutral kaons. The former asymmetry is a given combination ofRe (\\varepsilon ), Im (\\varepsilon ), and üɛ'ü. Moreover, the non-violating CP asymmetry allows a test for theχ PT predictions within the Zel'dovich approach for the final state interaction.

  3. Energy-charge correlation in the π+π-π0 decay of KL and of tagged neutral kaons

    We relate the asymmetries in the charged pion energy in the decay into π+π-π0 of KL and of the tagged neutral kaons. The former asymmetry is a given combination of R(ε), T(ε), and vertical stroke ε'vertical stroke . Moreover, the non-violating CP asymmetry allows a test for the χPT predictions within the Zel'dovich approach for the final state interaction. (orig.)

  4. A New Battery Energy Storage Charging/Discharging Scheme for Wind Power Producers in Real-Time Markets

    Minh Y Nguyen; Dinh Hung Nguyen; Yong Tae Yoon

    2012-01-01

    Under a deregulated environment, wind power producers are subject to many regulation costs due to the intermittence of natural resources and the accuracy limits of existing prediction tools. This paper addresses the operation (charging/discharging) problem of battery energy storage installed in a wind generation system in order to improve the value of wind power in the real-time market. Depending on the prediction of market prices and the probabilistic information of wind generation, wind pow...

  5. Transverse momentum and transverse mass distributions of charged hadrons produced in Au-Au collisions at high energies

    Liu Fu-Hu

    2008-01-01

    The transverse momentum distribution and the transverse mass distribution of charged hadrons produced in nucleus-nucleus collisions at high energies are described by using a two-cylinder model. The results calculated by the model are compared and found to be in agreement with the experimental data of the STAR and E895 Collaborations, measured in Au-Au collisions at the relativistic heavy ion collider (RHIC) and alternating-gradient synchrotron (AGS) energies, respectively. In the energy range concerned, the excitation degree of emission source close to the central axis of cylinders increases obviously with the collision centrality and incident energy increasing, but it does not show any obvious change with the increase of the (pseudo) rapidity in central collisions. The excitation degree of emission source close to the side-surface of cylinders does not show any obvious change with the collision centrality, the (pseudo) rapidity, and the incident energy increasing.

  6. The east-west effect of the muon charge ratio at energies relevant to the atmospheric neutrino anomaly

    During the propagation of cosmic rays in the atmosphere, pions and kaons are produced by the interactions with atmospheric nuclei, pions and kaons are produced, which subsequently decay in muons and neutrinos. Considering the decay chains, it is obviously that the ratio of positive to negative atmospheric muons, called the muon charge ratio: Rν = μ+/μ-, maps the neutrino production and carries information on the hadronic interactions, used in the calculations of atmospheric neutrino. Measurements of the charge ratio of atmospheric muons at low energy reveal information of interest for the atmospheric neutrino anomaly. Measurements of East-West effect of the muon charge ratio allow to check different models for the hadronic interaction and investigate the influence of the Earth's magnetic field. The WILLI detector, built in IFIN-HH (Horia Hulubei National Institute for Physics and Nuclear Engineering) Bucharest measures the charge ratio by the effective life-time of the stopped muons. While positive muons undergo a free decay with natural lifetime, negative muons form muonic atoms, leading to a shorter lifetime of negative muons. The measured decay curve of all muons is a superposition of several decay laws, containing 3 detector dependent constants, accounting for the stopping power in the materials and the detection efficiencies, which are determined by extensive detector simulations using GEANT. The investigation of the directional dependence of the muon charge ratio has been started with measurements in the East and West direction at a mean zenithal angle of 35 angle. Introducing the azimuthal anisotropy AEW = (RW - RE) / ( RW + RE) with RW and RE being the muon charge ratios measured in East and West direction, the preliminary results show a pronounced East-West effect. (authors)

  7. Synthesis and energy band characterization of hybrid molecular materials based on organic–polyoxometalate charge-transfer salts

    Tan, Chunxia [Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou City, Gansu Province (China); Traditional Chinese Medicine College of Gansu, Gansu (China); Bu, Weifeng, E-mail: buwf@lzu.edu.cn [Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou City, Gansu Province (China)

    2014-11-15

    A cationic amphiphilic molecule was synthesized and employed to encapsulate Lindqvist ([M{sub 6}O{sub 19}]{sup 2−}) and Keggin polyoxometalates ([SiM{sub 12}O{sub 40}]{sup 4−}, M=Mo, W) to form hybrid molecules through electrostatic interaction. The X-ray diffraction results illustrate that the former hybrids possess lamellar nanostructures in their solid states, while the latter hybrids show a cubic Im3m packing model with low intensities and poor long-range order. These hybrids have clear charge-transfer characters as shown in their deeper colors and UV–vis diffuse reflectance spectra. According to the reported reduction potentials of the POM acceptors and the band gaps deduced from their diffuse reflectance spectra, we have calculated the theoretical values of the lowest unoccupied molecular orbital (LUMO) position similar to the electron affinity (E{sub A}) of solid materials. Such energy level parameters are comparable to those of electroluminescence and electron-transport materials commonly used in organic electroluminescence devices. These organic–polyoxometalate charge-transfer salts have more advantages, such as higher decomposition temperatures, easier film fabrication and better electron affinities, which presumably would be used for electron-transport materials in the area of the electroluminescence. - Graphical abstract: Hybrid molecular materials with charge-transfer characters formed by a positively charged donor L and acceptors of the Lindqvist-type and Keggin-type POMs have lamellar and cubic structures in their solid state. - Highlights: • Charge-transfer salts are obtained by self-assembling POMs with an anthracene cation. • Their energy parameters are comparable to those of optoelectronic materials in OLEDs. • These POM-based hybrids could be applied in the area of optoelectronic devices.

  8. Synthesis and energy band characterization of hybrid molecular materials based on organic–polyoxometalate charge-transfer salts

    A cationic amphiphilic molecule was synthesized and employed to encapsulate Lindqvist ([M6O19]2−) and Keggin polyoxometalates ([SiM12O40]4−, M=Mo, W) to form hybrid molecules through electrostatic interaction. The X-ray diffraction results illustrate that the former hybrids possess lamellar nanostructures in their solid states, while the latter hybrids show a cubic Im3m packing model with low intensities and poor long-range order. These hybrids have clear charge-transfer characters as shown in their deeper colors and UV–vis diffuse reflectance spectra. According to the reported reduction potentials of the POM acceptors and the band gaps deduced from their diffuse reflectance spectra, we have calculated the theoretical values of the lowest unoccupied molecular orbital (LUMO) position similar to the electron affinity (EA) of solid materials. Such energy level parameters are comparable to those of electroluminescence and electron-transport materials commonly used in organic electroluminescence devices. These organic–polyoxometalate charge-transfer salts have more advantages, such as higher decomposition temperatures, easier film fabrication and better electron affinities, which presumably would be used for electron-transport materials in the area of the electroluminescence. - Graphical abstract: Hybrid molecular materials with charge-transfer characters formed by a positively charged donor L and acceptors of the Lindqvist-type and Keggin-type POMs have lamellar and cubic structures in their solid state. - Highlights: • Charge-transfer salts are obtained by self-assembling POMs with an anthracene cation. • Their energy parameters are comparable to those of optoelectronic materials in OLEDs. • These POM-based hybrids could be applied in the area of optoelectronic devices

  9. On the Remarkable Features of the Lower Limits of Charge and the Radiated Energy of Antennas as Predicted by Classical Electrodynamics

    Vernon Cooray; Gerald Cooray

    2016-01-01

    Electromagnetic energy radiated by antennas working in both the frequency domain and time domain is studied as a function of the charge associated with the current in the antenna. The frequency domain results, obtained under the assumption of sinusoidal current distribution, show that, for a given charge, the energy radiated within a period of oscillation increases initially with L/λ and then starts to oscillate around a steady value when L/λ > 1. The results show that for the energy radia...

  10. Charge state distributions of oxygen and carbon in the energy range 1 to 300 keV/e observed with AMPTE/CCE in the magnetosphere

    Observations of charge state distributions of oxygen and carbon are presented that were obtained with the charge-energy-mass spectrometer (CHEM) onboard the AMPTE/CCE space-craft. Data were selected for two different local time sectors (apogee at 1300 LT and 0300 LT, respectively), three L-ranges (48), and quiet to moderately disturbed days (Kp< or =4). The charge state distributions reveal the existence of all charge states of oxygen and carbon in the magnetosphere. The relative importance of the different charge states strongly depends on L and much less on local time. The observations confirm that the solar wind and the ionosphere contribute to the oxygen population, whereas carbon only originates from the solar wind. The L-dependence of the charge state distributions can be interpreted in terms of these different ion sources and of charge exchange and diffusion processes that largely influence the distribution of oxygen and carbon in the magnetosphere

  11. Effects of sevoflurane on adenylate cyclase and phosphodiesterases activity in brain of rats

    Objective: To investigate the effects of sevoflurane on c adenylate cyclase (AC) and phosphodiesterases (PDE) activity in the cerebrocortex, hippocampus and brain stem of rats, and to examine the role of cAMP in sevoflurane anesthesia. Methods: Fourty SD rats were delaminately designed and allocated randomly to 5 groups inhaling 1.5% sevoflurane i.e., no recovery (recovery group, n=8) and one hour after righting reflexrecovery (aware group, n=8). The brain tissues were rapidly dissected into cerebrocortex and hippocampus and brain stem.Then the adenylate cyclase and phosphodiesterases activity were assessed. Results: So far as the activity of AC is concerned, compared with the control group, the activity of AC in the cerebrocortex, hippocampus and brain stem brain stem of induction group and anesthesia group, the cerebrocortex, and hippocampus in the recovery group were significantly increased; compared with those in the anesthesia group, the activity of AC in the cerebrocortex, hippocampus and brain stem of aware group were significantly decreased (P<0.05); For the activity of PDE, compared with the control group, the activity of PDE in the cerebrocortex, hippocampus and brain stem in the induction group and anesthesia group was significantly decreased, compared with that in anesthesia group, the activity of PDE in the cerebrocortex, hippocampus and brain stem of recovery group and aware group was significantly increased (P<0.05). Conclusion: cAMP may play an important role in sevoflurane anesthesia. (authors)

  12. Path ensembles for conformational transitions in adenylate kinase using weighted--ensemble path sampling

    Bhatt, Divesh

    2009-01-01

    We perform first path sampling simulations of conformational transitions of semi--atomistic protein models. We generate an ensemble of pathways for conformational transitions between open and closed forms of adenylate kinase using weighted ensemble path sampling method. Such an ensemble of pathways is critical in determining the important regions of configuration space sampled during a transition. To different semi--atomistic models are used: one is a pure Go model, whereas the other includes level of residue specificity via use of Miyajawa--Jernigan type interactions and hydrogen bonding. For both the models, we find that the open form of adenylate kinase is more flexible and the the transition from open to close is significantly faster than the reverse transition. We find that the transition occurs via the AMP binding domain snapping shut at a fairly fast time scale. On the other hand, the flexible lid domain fluctuates significantly and the shutting of the AMP binding domain does not depend upon the positi...

  13. Leveraging the Mechanism of Oxidative Decay for Adenylate Kinase to Design Structural and Functional Resistances.

    Howell, Stanley C; Richards, David H; Mitch, William A; Wilson, Corey J

    2015-10-16

    Characterization of the mechanisms underlying hypohalous acid (i.e., hypochlorous acid or hypobromous acid) degradation of proteins is important for understanding how the immune system deactivates pathogens during infections and damages human tissues during inflammatory diseases. Proteins are particularly important hypohalous acid reaction targets in pathogens and in host tissues, as evidenced by the detection of chlorinated and brominated oxidizable residues. While a significant amount of work has been conducted for reactions of hypohalous acids with a range of individual amino acids and small peptides, the assessment of oxidative decay in full-length proteins has lagged in comparison. The most rigorous test of our understanding of oxidative decay of proteins is the rational redesign of proteins with conferred resistances to the decay of structure and function. Toward this end, in this study, we experimentally determined a putative mechanism of oxidative decay using adenylate kinase as the model system. In turn, we leveraged this mechanism to rationally design new proteins and experimentally test each system for oxidative resistance to loss of structure and function. From our extensive assessment of secondary structure, protein hydrodynamics, and enzyme activity upon hypochlorous acid or hypobromous acid challenge, we have identified two key strategies for conferring structural and functional resistance, namely, the design of proteins (adenylate kinase enzymes) that are resistant to oxidation requires complementary consideration of protein stability and the modification (elimination) of certain oxidizable residues proximal to catalytic sites. PMID:26266833

  14. The role of transcriptional regulation in maintaining the availability of mycobacterial adenylate cyclases

    Sarah J. Casey

    2014-03-01

    Full Text Available Mycobacterium species have a complex cAMP regulatory network indicated by the high number of adenylate cyclases annotated in their genomes. However the need for a high level of redundancy in adenylate cyclase genes remains unknown. We have used semiquantitiative RT-PCR to examine the expression of eight Mycobacterium smegmatis cyclases with orthologs in the human pathogen Mycobacterium tuberculosis, where cAMP has recently been shown to be important for virulence. All eight cyclases were transcribed in all environments tested, and only four demonstrated environmental-mediated changes in transcription. M. smegmatis genes MSMEG_0545 and MSMEG_4279 were upregulated during starvation conditions while MSMEG_0545 and MSMEG_4924 were downregulated in H2O2 and MSMEG_3780 was downregulated in low pH and starvation. Promoter fusion constructs containing M. tuberculosis H37Rv promoters showed consistent regulation compared to their M. smegmatis orthologs. Overall our findings indicate that while low levels of transcriptional regulation occur, regulation at the mRNA level does not play a major role in controlling cellular cyclase availability in a given environment.

  15. Mechanism of adenylate kinase: Site-directed mutagenesis versus x-ray and NMR

    Controversy is an integral part of scientific research and is often a precursor to the truth. However, this lesson has been learned in a very hard way in the case of the structure-function relationship of adenylate kinase (AK), which catalyzes the interconversion between MgATP+AMP and MgADP+ADP. While this small kinase has been considered a model kinase and the enzyme-substrate interaction of AK was among the first investigated by X-ray crystallography and NMR the substrate binding sites deduced from the early studies by these two powerful techniques (termed the X-ray model and the NMR model, respectively) were dramatically different. Ironically, both models have had substantial impact on researchers in related fields. The problems have finally been dealt with since 1987 by the interplay between site-directed mutagenesis, X-ray, and NMR. The purpose of this review is not only to summarize the current knowledge in the structure-function relationship of adenylate kinase but also to accurately document and critically analyze historical developments in the hope that history will not be repeated

  16. Identification of Adenyl Cyclase Activity in a Disease Resistance Protein in Arabidopsis thaliana

    Hussein, Rana

    2012-11-01

    Cyclic nucleotide, cAMP, is an important signaling molecule in animals and plants. However, in plants the enzymes that synthesize this second messenger, adenyl cyclases (ACs), remain elusive. Given the physiological importance of cAMP in signaling, particularly in response to biotic and abiotic stresses, it is thus important to identify and characterize ACs in higher plants. Using computational approaches, a disease resistance protein from Arabidopsis thaliana, At3g04220 was found to have an AC catalytic center motif. In an attempt to prove that this candidate has adenyl cyclases activity in vitro, the coding sequence of the putative AC catalytic domain of this protein was cloned and expressed in E. coli and the recombinant protein was purified. The nucleotide cyclase activity of the recombinant protein was examined using cyclic nucleotide enzyme immunoassays. In parallel, the expression of At3g04220 was measured in leaves under three different stress conditions in order to determine under which conditions the disease resistance protein could function. Results show that the purified recombinant protein has Mn2+ dependent AC activity in vitro, and the expression analysis supports a role for At3g04220 and cAMP in plant defense.

  17. Charge Dependence and Electric Quadrupole Effects on Single-Nucleon Removal in Relativistic and Intermediate Energy Nuclear Collisions

    Norbury, John W.

    1992-01-01

    Single nucleon removal in relativistic and intermediate energy nucleus-nucleus collisions is studied using a generalization of Weizsacker-Williams theory that treats each electromagnetic multipole separately. Calculations are presented for electric dipole and quadrupole excitations and incorporate a realistic minimum impact parameter, Coulomb recoil corrections, and the uncertainties in the input photonuclear data. Discrepancies are discussed. The maximum quadrupole effect to be observed in future experiments is estimated and also an analysis of the charge dependence of the electromagnetic cross sections down to energies as low as 100 MeV/nucleon is made.

  18. Calculation of the electrostatic energy of formed of two charged helices on rods in a generalized braid geometry

    Lee, D J

    2013-01-01

    This is a technical document that outlines a calculation of an electrostatic interaction energy between two rods, with charge helices on them, forming a braid. We deal here with screened electrostatics. A general braid geometry is considered, though to obtain local expressions for the energy the curvature of the rods is considered to be small. Further approximations are made for small tilt angle. This is a generalization of the calculations given in the supplemental material of [R. Cortini et Al, Biophys. J. 101 875 (2011)] for a straight symmetric braid structure, using a different method of calculation where the braid geometry does not need to be supposed a priori.

  19. Nonperturbative shell correction to the Bethe-Bloch formula for the energy losses of fast charged particles

    Matveev, V. I.; Makarov, D. N.

    2011-09-01

    A simple method including nonperturbative shell corrections has been developed for calculating energy losses on complex atoms. The energy losses of fast highly charged ions on neon, argon, krypton, and xenon atoms have been calculated and compared with experimental data. It has been shown that the inclusion of the non-perturbative shell corrections noticeably improves agreement with experimental data as compared to calculations by the Bethe-Bloch formula with the standard corrections. This undoubtedly helps to reduce the number of fitting parameters in various modifications of the Bethe-Bloch formula, which are usually determined semiempirically.

  20. Quightness: A proposed figure of merit for sources of low-energy, high-charge-state ions

    A variety of ion sources, including the EBIS and ECRIS, are distinguished by their ability to produce low-energy ions of very high charge state. It would be useful to have some figure of merit that is particularly sensitive to this performance. I propose here such a quantity, called ''Quightness,'' which is related to brightness but which enhances the contrast between sources supplying multicharged ions of low energy. The rationale for introducing this quantity, its etymology and relationship to other figures of merit, and some representative values are presented

  1. On the Remarkable Features of the Lower Limits of Charge and the Radiated Energy of Antennas as Predicted by Classical Electrodynamics

    Vernon Cooray

    2016-05-01

    Full Text Available Electromagnetic energy radiated by antennas working in both the frequency domain and time domain is studied as a function of the charge associated with the current in the antenna. The frequency domain results, obtained under the assumption of sinusoidal current distribution, show that, for a given charge, the energy radiated within a period of oscillation increases initially with L/λ and then starts to oscillate around a steady value when L/λ > 1. The results show that for the energy radiated by the antenna to be equal to or larger than the energy of one photon, the oscillating charge in the antenna has to be equal to or larger than the electronic charge. That is, U ≥ hν or UT ≥ h ⇒ q ≥ e, where U is the energy dissipated over a period, ν is the frequency of oscillation, T is the period, h is Planck’s constant, q is the rms value of the oscillating charge, and e is the electronic charge. In the case of antennas working in the time domain, it is observed that UΔt ≥ h/4π ⇒ q ≥ e, where U is the total energy radiated, Δt is the time over which the energy is radiated, and q is the charge transported by the current. It is shown that one can recover the time–energy uncertainty principle of quantum mechanics from this time domain result. The results presented in this paper show that when quantum mechanical constraints are applied to the electromagnetic energy radiated by a finite antenna as estimated using the equations of classical electrodynamics, the electronic charge emerges as the smallest unit of free charge in nature.

  2. Design of Solar/Electric Powered Hybrid Vehicle (SEPHV System with Charge Pattern Optimization for Energy Cost

    T.Balamurugan

    2014-01-01

    Full Text Available This paper proposes a Solar Electric Powered Hybrid Vehicle (SEPHV system which solves the major problems of fuel and pollution. An electric vehicle usually uses a battery which has been charged by external electrical power supply. All recent electric vehicles present a drive on AC power supplied motor. An inverter set is required to be connected with the battery through which AC power is converted to DC power. During this conversion many losses take place and also the maintenance cost of the AC System is very high. The proposed topology has the most feasible solar/electric power generation system mounted on the vehicle to charge the battery during all durations. With a view of providing ignited us to develop this “Solar/Electric Powered Hybrid Vehicle” [SEPHV].This multi charging vehicle can charge itself from both solar and electric power. The vehicle is altered out of a Maruti Omni vehicle by replacing its engine with a 1.2HP, 24V Permanent Magnet DC [PMDC] Motor. The Supply to the motor is obtained from a battery set of 12V, 150AH. The household electric supply of 230V is reduced with a step-down transformer to 48V and then it is converted to the DC with a rectifying unit to charge the battery. Two solar panels each with a rating of 230watts are attached to the top of the Vehicle to grab the solar energy and is controlled with a help of charge controller. The SEPHV can be driven by 1.2 HP PMDC motor consisting of two 230 watts PV panel in the voltage rating of 24 V. The power which is absorbed by the PV panel is stored into the four 150 AH 12 V batteries. When there is no presence of sun, electric power supply act as an auxiliary energy source. For controlling speed of the motor, a switch is designed with four tapping, provided with different values of resistance at each tapping. It acts as a speed control switch for Solar/Electric Powered Hybrid Vehicle. This type of technique is to reduce the running cost and increasing the running

  3. Effect of dense plasmas on exchange-energy shifts in highly charged ions: An alternative approach for arbitrary perturbation potentials

    Rosmej, F. [Sorbonne Universites, Pierre et Marie Curie, UMR 7605, case 128, 4 place Jussieu, F-75252 Paris (France); Ecole Polytechnique, Laboratoire pour l' Utilisation des Lasers Intenses LULI, Physique Atomique dans les Plasmas Denses PAPD, F-91228 Palaiseau (France); Bennadji, K. [Sorbonne Universites, Pierre et Marie Curie, UMR 7605, case 128, 4 place Jussieu, F-75252 Paris (France); ExtreMe Matter Institute EMMI, GSI Helmholtz Centre of Heavy Ion Research, Planckstrasse 1, D-64291 Darmstadt (Germany); Lisitsa, V. S. [Russian Research Center Kurchatov, Laboratory of Radiation Theory, Kurchatov Square 1, 123182 Moscow (Russian Federation)

    2011-09-15

    An alternative method of calculation of dense plasma effects on exchange-energy shifts {Delta}E{sub x} of highly charged ions is proposed which results in closed expressions for any plasma or perturbation potential. The method is based on a perturbation theory expansion for the inner atomic potential produced by charged plasma particles employing the Coulomb Green function method. This approach allows us to obtain analytic expressions and scaling laws with respect to the electron temperature T, density n{sub e}, and nuclear charge Z. To demonstrate the power of the present method, two specific models were considered in detail: the ion sphere model (ISM) and the Debye screening model (DSM). We demonstrate that analytical expressions can be obtained even for the finite temperature ISM. Calculations have been carried out for the singlet 1s2p{sup 1} P{sub 1} and triplet 1s2p{sup 3} P{sub 1} configurations of He-like ions with charge Z that can be observed in dense plasmas via the He-like resonance and intercombination lines. Finally we discuss recently available purely numerical calculations and experimental data.

  4. Plug-in hybrid electric vehicle charge pattern optimization for energy cost and battery longevity

    This paper examines the problem of optimizing the charge pattern of a plug-in hybrid electric vehicle (PHEV), defined as the timing and rate with which the PHEV obtains electricity from the power grid. The optimization goal is to simultaneously minimize (i) the total cost of fuel and electricity and (ii) the total battery health degradation over a 24-h naturalistic drive cycle. The first objective is calculated for a previously-developed stochastic optimal PHEV power management strategy, whereas the second objective is evaluated through an electrochemistry-based model of anode-side resistive film formation in lithium-ion batteries. The paper shows that these two objectives are conflicting, and trades them off using a non-dominated sorting genetic algorithm. As a result, a Pareto front of optimal charge patterns is obtained. The effects of electricity price and trip schedule on the optimal Pareto points and the PHEV charge patterns are analyzed and discussed. (author)

  5. Key elements of space charge compensation on a low energy high intensity beam injector.

    Peng, Shixiang; Lu, Pengnan; Ren, Haitao; Zhao, Jie; Chen, Jia; Xu, Yuan; Guo, Zhiyu; Chen, Jia'er; Zhao, Hongwei; Sun, Liangting

    2013-03-01

    Space charge effect (SCE) along the beam line will decrease beam quality. Space charge compensation (SCC) with extra gas injection is a high-efficiency method to reduce SCE. In this paper, we will report the experimental results on the beam profile, potential distribution, beam emittance, and beam transmission efficiency of a 35 keV∕90 mA H(+) beam and a 40 keV∕10 mA He(+) beam compensated by Ar∕Kr. The influence of gas type, gas flow, and injection location will be discussed. Emphasis is laid on the consideration of SCC when designing and commissioning a high intensity ion beam injector. Based on measured data, a new definition of space charge compensation degree is proposed. PMID:23556812

  6. Key elements of space charge compensation on a low energy high intensity beam injector

    Peng Shixiang; Lu Pengnan; Ren Haitao; Zhao Jie; Chen Jia; Xu Yuan; Guo Zhiyu; Chen Jia' er [Institution of Nuclear Science and Technology (INST), State Key Laboratory of Nuclear Physics and Technology (KLNPT), Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Zhao Hongwei; Sun Liangting [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2013-03-15

    Space charge effect (SCE) along the beam line will decrease beam quality. Space charge compensation (SCC) with extra gas injection is a high-efficiency method to reduce SCE. In this paper, we will report the experimental results on the beam profile, potential distribution, beam emittance, and beam transmission efficiency of a 35 keV/90 mA H{sup +} beam and a 40 keV/10 mA He{sup +} beam compensated by Ar/Kr. The influence of gas type, gas flow, and injection location will be discussed. Emphasis is laid on the consideration of SCC when designing and commissioning a high intensity ion beam injector. Based on measured data, a new definition of space charge compensation degree is proposed.

  7. Accurate Detection of Adenylation Domain Functions in Nonribosomal Peptide Synthetases by an Enzyme-linked Immunosorbent Assay System Using Active Site-directed Probes for Adenylation Domains.

    Ishikawa, Fumihiro; Miyamoto, Kengo; Konno, Sho; Kasai, Shota; Kakeya, Hideaki

    2015-12-18

    A significant gap exists between protein engineering and enzymes used for the biosynthesis of natural products, largely because there is a paucity of strategies that rapidly detect active-site phenotypes of the enzymes with desired activities. Herein, we describe a proof-of-concept study of an enzyme-linked immunosorbent assay (ELISA) system for the adenylation (A) domains in nonribosomal peptide synthetases (NRPSs) using a combination of active site-directed probes coupled to a 5'-O-N-(aminoacyl)sulfamoyladenosine scaffold with a biotin functionality that immobilizes probe molecules onto a streptavidin-coated solid support. The recombinant NRPSs have a C-terminal His-tag motif that is targeted by an anti-6×His mouse antibody as the primary antibody and a horseradish peroxidase-linked goat antimouse antibody as the secondary antibody. These probes can selectively capture the cognate A domains by ligand-directed targeting. In addition, the ELISA technique detected A domains in the crude cell-free homogenates from the Escherichia coli expression systems. When coupled with a chromogenic substrate, the antibody-based ELISA technique can visualize probe-protein binding interactions, which provides accurate readouts of the A-domain functions in NRPS enzymes. To assess the ELISA-based engineering of the A domains of NRPSs, we reprogramed 2,3-dihydroxybenzoic acid (DHB)-activating enzyme EntE toward salicylic acid (Sal)-activating enzymes and investigated a correlation between binding properties for probe molecules and enzyme catalysts. We generated a mutant of EntE that displayed negligible loss in the kcat/Km value with the noncognate substrate Sal and a corresponding 48-fold decrease in the kcat/Km value with the cognate substrate DHB. The resulting 26-fold switch in substrate specificity was achieved by the replacement of a Ser residue in the active site of EntE with a Cys toward the nonribosomal codes of Sal-activating enzymes. Bringing a laboratory ELISA technique

  8. Polarization Energies at Organic-Organic Interfaces: Impact on the Charge Separation Barrier at Donor-Acceptor Interfaces in Organic Solar Cells.

    Ryno, Sean M; Fu, Yao-Tsung; Risko, Chad; Brédas, Jean-Luc

    2016-06-22

    We probe the energetic landscape at a model pentacene/fullerene (C60) interface to investigate the interactions between positive and negative charges, which are critical to the processes of charge separation and recombination in organic solar cells. Using a polarizable force field, we find that polarization energy, i.e., the stabilization a charge feels due to its environment, is larger at the interface than in the bulk for both a positive and a negative charge. The combination of the charge being more stabilized at the interface and the Coulomb attraction between the charges results in a barrier to charge separation at the pentacene/C60 interface that can be in excess of 0.7 eV for static configurations of the donor and acceptor locations. However, the impact of molecular motions, i.e., the dynamics, at the interface at room temperature results in a distribution of polarization energies and in charge separation barriers that can be significantly reduced. The dynamic nature of the interface is thus critical, with the polarization energy distributions indicating that sites along the interface shift in time between favorable and unfavorable configurations for charge separation. PMID:27244215

  9. Polarization Energies at Organic–Organic Interfaces: Impact on the Charge Separation Barrier at Donor–Acceptor Interfaces in Organic Solar Cells

    Ryno, Sean

    2016-05-31

    We probe the energetic landscape at a model pentacene/fullerene-C60 interface to investigate the interactions between positive and negative charges, which are critical to the processes of charge separation and recombination in organic solar cells. Using a polarizable force field, we find that polarization energy, i.e. the stabilization a charge feels due to its environment, is larger at the interface than in the bulk for both a positive and a negative charge. The combination of the charge being more stabilized at the interface and the Coulomb attraction between the charges, results in a barrier to charge separation at the pentacene-C60 interface that can be in excess of 0.7 eV for static configurations of the donor and acceptor locations. However, the impact of molecular motions, i.e., the dynamics, at the interface at room temperature results in a distribution of polarization energies and in charge separation barriers that can be significantly reduced. The dynamic nature of the interface is thus critical, with the polarization energy distributions indicating that sites along the interface shift in time between favorable and unfavorable configurations for charge separation.

  10. Topmetal-II-: a direct charge sensor for high energy physics and imaging applications

    Gao, C.; Huang, G.; Sun, X.

    2016-01-01

    Topmetal-II-, a direct charge sensor, was manufactured in an XFAB 350 nm CMOS process. The Topmetal-II- sensor features a 72 × 72 pixel array with an 83 μm pixel pitch which collects and measures charge directly from the surrounding media. We introduce the implementation of the circuitry in the sensor including an analogue readout channel and a column based digital readout channel. The analogue readout channel allows the access to the full waveform from each pixel through a time-shared multiplexing. The digital readout channel records hits identified by an individually settable threshold in each pixel. Some simulation and preliminary test results are also discussed.

  11. Topmetal-II−: a direct charge sensor for high energy physics and imaging applications

    Topmetal-II−, a direct charge sensor, was manufactured in an XFAB 350 nm CMOS process. The Topmetal-II− sensor features a 72 × 72 pixel array with an 83 μm pixel pitch which collects and measures charge directly from the surrounding media. We introduce the implementation of the circuitry in the sensor including an analogue readout channel and a column based digital readout channel. The analogue readout channel allows the access to the full waveform from each pixel through a time-shared multiplexing. The digital readout channel records hits identified by an individually settable threshold in each pixel. Some simulation and preliminary test results are also discussed

  12. Physical chemistry of charged interfaces: multi-scale modelling and applications to energy

    This article presents the advantages of a multi-scale modelling strategy for the understanding of systems with charged interfaces. On the one hand, one can simulate a complex system at different levels, depending on the relevant length and time scales for a given physical chemistry problem. On the other hand, one should make the link between the various levels of description, e.g. following a bottom-up approach. The case of charged porous materials, in particular clay minerals, is illustrated here by discussing physical chemistry issues that arise in the context of geological disposal of nuclear wastes and CO2 sequestration. (author)

  13. X-ray resonant photoexcitation: linewidths and energies of Kα transitions in highly charged Fe ions.

    Rudolph, J K; Bernitt, S; Epp, S W; Steinbrügge, R; Beilmann, C; Brown, G V; Eberle, S; Graf, A; Harman, Z; Hell, N; Leutenegger, M; Müller, A; Schlage, K; Wille, H-C; Yavaş, H; Ullrich, J; Crespo López-Urrutia, J R

    2013-09-01

    Photoabsorption by and fluorescence of the Kα transitions in highly charged iron ions are essential mechanisms for x-ray radiation transfer in astrophysical environments. We study photoabsorption due to the main Kα transitions in highly charged iron ions from heliumlike to fluorinelike (Fe24+ to Fe17+) using monochromatic x rays around 6.6 keV at the PETRA III synchrotron photon source. Natural linewidths were determined with hitherto unattained accuracy. The observed transitions are of particular interest for the understanding of photoexcited plasmas found in x-ray binary stars and active galactic nuclei. PMID:25166661

  14. Improving charge transport property and energy transfer with carbon quantum dots in inverted polymer solar cells

    Liu, Chunyu; Chang, Kaiwen; Guo, Wenbin, E-mail: guowb@jlu.edu.cn, E-mail: chenwy@jlu.edu.cn, E-mail: dawei.yan@hotmail.com; Li, Hao; Shen, Liang [State Key Laboratory on Integrated Optoelectronics, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Chen, Weiyou, E-mail: guowb@jlu.edu.cn, E-mail: chenwy@jlu.edu.cn, E-mail: dawei.yan@hotmail.com [College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yan, Dawei, E-mail: guowb@jlu.edu.cn, E-mail: chenwy@jlu.edu.cn, E-mail: dawei.yan@hotmail.com [Research Center of Laser Fusion, CAEP, P.O. Box 919-983, Mianyang 621900 (China)

    2014-08-18

    Carbon quantum dots (Cdots) are synthesized by a simple method and introduced into active layer of polymer solar cells (PSCs). The performance of doped devices was apparently improved, and the highest power conversion efficiency of 7.05% was obtained, corresponding to a 28.2% enhancement compared with that of the contrast device. The charge transport properties, resistance, impedance, and transient absorption spectrum are systematically investigated to explore how the Cdots affect on PSCs performance. This study reveals the importance of Cdots in enhancing the efficiency of PSCs and gives insight into the mechanism of charge transport improvement.

  15. Advice and recommendations to the US Department of Energy in response to the charge letter of September 20, 1996

    In Jan. 1996, the Fusion Energy Advisory Committee (FEAC) provided recommendations to DOE on how to restructure the fusion program in light of compressional guidance and budget realities. DOE endorsed these recommendations and prepared a strategic plan. The FEAC report concluded that the goals of the restructured program could most effectively be accomplished at a funding level of $275 million per year, including Federal government management costs. DOE requested that Congress appropriate $255.6 million in FY97 for the fusion energy sciences program exclusive of Federal government management costs (about $8 million). On Sept. 11, 1996, the Energy and Water Development Conference Committee settled on a FY97 appropriation for the fusion energy sciences program of $232.5 million. This report contains the response to the charge letter, on how the program described in the strategic plan could be changed to make it consistent with the $232.5 million appropriation

  16. Charge Exchange in Low-Energy H, D + C4+ Collisions with Full Account of Electron Translation

    N. Vaeck

    2002-03-01

    Full Text Available We report the application of the quantum approach, which takes full account of electron translation at low collisional energies, to the charge exchange process H, D + C4+ → H+, D+ + C3+(3s; 3p; 3d. The partial and the total integral cross sections of the process are calculated in the energy range from 1 till 60 eV/amu. It is shown that the present results are independent from the upper integration limit for numerical solution of the coupled channel equations although nonadiabatic couplings remain nonzero up to infinity. The calculated partial and total cross sections are in agreement with the previous low-energy calculations and the available experimental data. It is shown that for low collisional energies the isotopic effect takes place. The observed effect is explained in terms of the nonadiabatic dynamics.

  17. Wideband energy harvesting using a combination of an optimized synchronous electric charge extraction circuit and a bistable harvester

    The challenge of variable vibration frequencies for energy harvesting calls for the development of wideband energy harvesters. Bistability has been proven to be a potential solution. Optimization of the energy extraction is another important objective for energy harvesting. Nonlinear synchronized switching techniques have demonstrated some of the best performances. This paper presents a novel energy harvesting solution which combines these two techniques: the OSECE (optimized synchronous electric charge extraction) technique is used along with a BSM (buckled-spring–mass) bistable generator to achieve wideband energy harvesting. The effect of the electromechanical coupling coefficient on the harvested power for the bistable harvester with the nonlinear energy extraction technique is discussed for the first time. The performances of the proposed solution for different levels of electromechanical coupling coefficients in the cases of chirp and noise excitations are compared against the performances of the bistable harvester with the standard technique. It is shown that the OSECE technique is a much better option for wideband energy harvesting than the standard circuit. Moreover, the harvested energy is drastically increased for all excitations in the case of low electromechanical coupling coefficients. When the electromechanical coupling coefficient is high, the performance of the OSECE technique is not as good as the standard circuit for forward sweeps, but superior for the reverse sweep and band-limited noise cases. However, considering that real excitation signals are more similar to noise signals, the OSECE technique enhances the performance. (paper)

  18. Electron-emission processes in highly charged Ar and Xe ions impinging on highly ordered pyrolytic graphite at energies just above the kinetic threshold

    Bodewits, E.; Hoekstra, R.; Dobes, K.; Aumayr, F.

    2014-01-01

    At keV energies, many electronic processes contribute to the emission of secondary electrons in the interaction of highly charged ions on surfaces. To unravel contributions resulting from isolated hollow atoms in front of the surface or embedded in the electron gas of the target, heavy highly charge

  19. Distributed Bus Signaling Control for a DC Charging Station with Multi Paralleled Flywheel Energy Storage System

    Sun, Bo; Dragicevic, Tomislav; Vasquez, Juan Carlos; Guerrero, Josep M.; Savaghebi, Mehdi

    Fast charging stations (FCS) will become an essential part of future transportation systems with an increasing number of electrical vehicles. However, since these FCS plugs have power ratings of up to 100 kW, serious stress caused by large number of FCS could threaten the stability of the main...

  20. BIOTIC STRESS IMPACT ON ACTIVITY OF VARIOUS FORMS OF ADENYLATE CYCLASE IN ORGANELLES OF POTATO PLANT CELLS

    Lomovatskaya L.A.

    2006-12-01

    Full Text Available Notwithstanding significant interest towards study of adenylate cyclase plant signal system, there is still no complete picture of functioning and regulation mechanisms of this signal system in plants under biotic stress. With this in view, our study was aimed at identification of various forms of adenylate cyclase (transmembrane and “soluble” in the nucleus and chloroplasts of potato cells and modulation of their activity under the impact of exopolysaсcharides ofpotato ring rot pathogen. The investigations conducted allowed to conclude that two forms of adenylate cyclase function in nuclei and chloroplasts of potato plants: transmembrane and “soluble”. Activity of these forms of the enzyme extracted from plant cells of the two potato varieties contrasted by resistance to potato ring rot pathogen Clavibacter michiganensis subsp. sepedonicus, changed in the reverse manner with the mediated impact of exopolysaсcharides secreted by virulent and mucinous strain of bacterial pathogen: in the plants of resistant сultivar it increased, in the plants of sensitive сultivar it was oppressed. It was concluded that activity of both forms of adenylate cyclase directly depended on the degree of resistance of a particular potato variety to given pathogen.