International Nuclear Information System (INIS)

The decay channels of the Ar 2s"-"1 and 2p"-"1 and Kr 3p"-"1 and 3d"-"1 electronic hole states have been investigated by means of photoelectron-photoion coincidence measurements following innershell ionization using synchrotron radiation. With the method of final ion-charge resolving electron spectroscopy it has become possible to disentangle different contributions to the electron spectrum and to determine the decay probabilities P(nl"-"1#->#n+) of the above-mentioned hole states (nl"-"1) to the final ionic charge states n+. A high correlation with threefold or even fourfold charged ions has been found in all cases. Possible decay routes, via cascade or direct double Auger processes, are discussed on the basis of energy-level schemes calculated with the Hartree-Fock method. Special emphasis is laid on the examination of the Kr 3p"-"1 ...

Energy Technology Data Exchange (ETDEWEB)

Beam-foil spectroscopy techniques have been used to study intercombination transitions in Be-like Fe{sup 22+} and B-like Fe{sup 21+}. The method of time delayed spectroscopy was used to identify the Be-like 2s{sup 2} {sup 1}S{sub 0}-2s2p {sup 3}P{sub 1} and B-like 2s{sup 2}2p {sup 2}P{sub 3/2}-2s2p{sup 2} {sup 4}P{sub 5/2} transitions. Intensity decay curves for these transitions were recorded and level lifetimes were obtained. The latter were found to be 17.5 {+-} 1.5 ns for the Be-like 2s2p {sup 3}P{sub 1} level and 14.8 {+-} 1.0 ns for the B-like 2s2p{sup 2} {sup 4}P{sub 5/2} level. (orig.).

CERN Document Server

An electroweak singlet scalar can couple to pairs of vector bosons through loop-induced dimension five operators. Compared to a Standard Model Higgs boson, the singlet decay widths in the diphotons and Z gamma channels are generically enhanced, while decays into massive final states like WW and ZZ are kinematically disfavored. The overall event rates into gamma gamma and Z gamma can exceed the Standard Model expectations by orders of magnitude. Such a singlet may appear as a resonant signal in the gamma gamma and Z gamma channels, even with a mass above the WW kinematic threshold.

International Nuclear Information System (INIS)

A new channel of nonlinear ionization of quantum system in a strong laser field is discussed. The probability of spontaneous radiation decay from the ground state in a short-range potential to the final Volkov wave function, is calculated by the first order of the perturbation theory. It is shown that this process at high intensities of the laser field will be comparable with the high harmonic generation. (orig.)

CERN Document Server

Recent advances in our understanding of the higher-wave quarkonia have generated much interests in quarkonium physics. However most are devoted to inclusive decays and productions. Experimental data of several two-body exclusive decay channels of P-wave charmonia such as \\pi \\pi and p \\bar p are available and some have recently been re-measured by the BES collaboration. It is not clear from the outset that color octet is needed for these exclusive channels. Indeed only color singlet has been used in the past and reasonable agreement with data was found. Contrary to these old results, we provide theoretical arguments for the inclusion of color octet and perform explicit calculations to back this up.

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Doubly-excited 2s{sup -1}2p{sup -1}3pnp autoionizing resonance series of Ne atom as well as autoionizing resonances in the 2s region of Na and Mg atoms have been studied with monochromatized synchrotron radiation. Use of charge-separated photoion-yield method allowed us to detect these weak resonances in a clarified way in the yield curves of doubly-charged ions. The observed resonance states have been interpreted with the help of MCDF calculations, and the decay processes of these resonance states are discussed briefly.

International Nuclear Information System (INIS)

Neutron-hole states in /sup 87/Sr were studied by means of the /sup 88/Sr("3He,#alpha#)/sup 87/Sr reaction at 36 MeV. Angular distribution measurements were carried out from 3"0 to 41"0 (lab) and analyzed with the zero-range distorted-wave Born approximation method. Spectroscopic factors have been determined for about 50 discrete levels in /sup 87/Sr located below 6 MeV excitation energy and for the three lowest isobaric analog states 2p(3/2, 1f(5/2, and 2p(1/2 observed around 11 MeV. Many l = 1 and l = 3 discrete levels are observed in the 3--6 MeV excitation energy range. In addition, a large part of the 1f-2p strength is found to lie in the higher-lying continuum up to 13 MeV (about 10% and 40% for the l = 1 and 3 contributions, respectively). The distribution of the 1f-2p neutron-hole strength is compared to previous ...

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We investigate the two-body decay modes {rho}{rho}, {pi}{pi}{sup *} (1300) and {sigma}{sigma} of the f{sub 0}(1500), all leading to the four pion decay channel, in a three-state mixing scheme, where the f{sub 0}(1500) is a mixture of the lowest lying scalar glueball with the nearby isoscalar states of the 0{sup ++}Q Q-bar nonet. In the leading order of this scheme, the decay mechanism of the f{sub 0}(1500) proceeds dominantly via its quarkonium components, which can be described in the framework of the {sup 3}P{sub 0} pair creation model. We predict the hierarchy of decay branching ratios B with B({rho}{rho}) {>=} B({pi}{pi}) {>=} B({sigma}{sigma}) > B({pi}{pi}{sup *}), providing a key signature of the proposed mixing scheme in this leading order approach. (authors)

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A summary of the latest results of Standard Model Higgs boson searches from CDF and D0 presented at the DIS 2007 conference is reported in this paper. All analyses presented use 1 fb{sup -1} of Tevatron data. The strategy of the different analyses is determined by the Higgs production mechanism and decay channel.

CERN Document Server

A search for the doubly charged Higgs boson, a member of $SU(2)_L$ scalar triplet $\\Phi$ participating in the seesaw mechanism of type II, in $pp$ collisions at $\\sqrt{s}=7$~TeV is presented. The data correspond to an integrated luminosity of 36 $\\text{pb}^{-1}$ collected by the CMS experiment at the LHC. The inclusive search is performed in events with three and four isolated charged leptons of all flavours originating from the decays of pair produced triplet components $\\Phi^{++}\\Phi^{--}$ and $\\Phi^{++}\\Phi^{-}.$ With the present collected luminosity the CMS experiment is sensitive to the $\\Phi$ mass range in which the possible decays $\\Phi^{++}\\to W^{+}W^{+}$ are forbidden kinematically. No signal excess is observed and lower limits at the 95\\% confidence level are set on the $\\Phi^{++}$ mass of 156\\GeV in the $\\mu\\mu$ channel, $154\\GeV$ in e$\\mu$ channel, of $144\\GeV$ in $ee$ ...

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Decay mechanism of H{sub 2}{sup -} anions produced by {gamma}-ray or X-ray radiolysis of solid para-H{sub 2} (p-H{sub 2}) has been studied using high-resolution ESR spectroscopy in the temperature range between 2.7-6.6 K. The results can be summarized as follows; First, the decay rate constant of the H{sub 2}{sup -} anion is not proportional to initial yields of reactive species such as H radical and cation but proportional to concentrations of HD and D{sub 2} impurities in p-H{sub 2}. Second, ESR spectra assigned as electron bubbles were observed in solid p-H{sub 2} containing large amount of HD or D{sub 2} (11 mol %), while they were not observed in pure solid p-H{sub 2}. Third, the decay rate constant of the H{sub 2}{sup -} anion increases with the decrease in temperature between 2.7-5 K, while it decreases with the decrease between 5-6.6 K. Fourth, the decay ...

Energy Technology Data Exchange (ETDEWEB)

The thesis deals with measurement of the mass of the W boson at LEP2, based on the direct reconstruction of its decay products in the hadronic channel. A set of procedures necessary for the extraction of the W mass from the experimental data collected with the DELPHI detector in 1997 was developed (search of optimal variables for the event selection, development of a special method of kinematical reconstruction). The measured value of the mass was interpreted in the framework of the Standard Model, allowing to constrain the mass of the Higgs boson. A substantial part of the work is devoted to systematic effects due to the interactions between the hadronic decay products of the W bosons (colour reconnection and Bose-Einstein correlations), which may significantly influence the measurement of their mass. (author) 53 refs., 104 figs., 33 tabs.

International Nuclear Information System (INIS)

The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the ...

International Nuclear Information System (INIS)

Excitation functions (#alpha#,3n) and (#alpha#,4n) for "2"0"9Bi have been measured up to 60 MeV #alpha#-particle energy. The excitation functions are measured at 15#alpha#-particle energies by a stack foil technique in two steps. Excitation functions for the above two reactions have been reported for the first time in the energy range from 40 to 60 MeV. The measured experimental values are compared with the geometry-dependent hybrid (GDH) model in which the emission of particles prior to the equilibrium decay is taken into account whenever the interaction of projectile with the target nucleus is considered. It is found that the compound nucleus decay mechanism alone is unable to explain the experimental trend of our data. The initial exciton number 4 with different configurations has been tested and it is concluded that the configuration (2n + 2p + 0h) gives the best fit to the experimental data. ...

CERN Document Server

Several signatures of new physics accessible at the LHC either suffer from top-quark production as a significant background or contain top quarks themselves. In this talk, we present results on top quark physics obtained from the first LHC data collected by the CMS experiment.They include measurements of the top pair production cross section in various channels and their combination, measurements of the top quark mass, the single top cross section, a search for new particles decaying into top pairs, and a first look at the charge asymmetry.

British Library Electronic Table of Contents (United Kingdom)

Resonant scattering of atoms with formation of the Feshbach resonance in the presence of a laser radiation coupling the levels of two bound atoms (a molecule) is considered. The laser field leads to a second resonance in scattering and broadening of resonances, which facilitates the possibility of experimental observation of asymmetry of the total scattering cross-section arising because of interference between resonant and potential scatterings. The effects associated with interference of the two channels of decay of a bound system of two atoms (a molecule) in the laser field are studied. An expression is obtained for the scattering length in collision of two cold atoms in the field of laser radiation.

International Nuclear Information System (INIS)

Dysprosium ion doped fluorophosphate glasses with compositions of PKMAFDy: (56-x/2) P2O5+17K2O+8Al2O3+(15-x/2)MgO+4AlF3+xDy2O3 (x=0.01, 0.05, 0.1, 1.0 and 2.0 mol%) have been prepared by melt quenching technique and are characterized by optical absorption, emission spectra and fluorescence lifetime measurements. The observed bands in the absorption spectrum are analysed by using free-ion Hamiltonian (HFI) model. The Judd-Ofelt (JO) analysis has been performed and the intensity parameters (??, ?=2, 4, 6) have been evaluated that are used to predict radiative properties. From emission spectra, the effective bandwidth (??eff) and the stimulated emission cross-section (?(?p)) were evaluated. The fluorescence decay from the 4F9/2 level of Dy3+ ions have been measured by monitoring the intense 4F9/2#->#6H13/2 transition (573 nm). The lifetimes (?) are found to decrease with increasing concentration due to concentration ...

Energy Technology Data Exchange (ETDEWEB)

Condensing two-phase channel flow occurs in many industrial applications, including heating and refrigeration systems. It can also occur in certain nuclear reactor accidents. For example, during a small-break loss-of-coolant accident in a pressurized water reactor, following the partial depletion of the primary coolant, condensation of steam on the primary side of the steam generator tubes can provide a heat sink for disposal of the decay heat generated in the reactor core. Condensing two-phase flow can also play an important role in the operation of the passive emergency cooling system in the advanced simplified boiling water reactor. Here, steady-state condensation in the presence of a noncondensable in a concurrent two-phase channel flow is analyzed using a two-fluid model. The effect of noncondensables on the combined heat transfer at the liquid-gas mixture interphase is accounted for by using the stagnant film model, ...

CERN Document Server

Using 347.5 fb-1 of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244*10^3 signal events for the D+ --> K- pi+ e+ nu_e decay channel are analyzed. This decay mode is dominated by the \\bar{K}^*(892)^0 contribution. We determine the \\bar{K}^*(892)^0 parameters: m_{K^*(892)^0}=(895.4 +- 0.2 +- 0.2) MeV/c^{2}, \\Gamma^0_{K^*(892)^0}=(46.5 +- 0.3 +- 0.2) MeV/c^{2} and the Blatt-Weisskopf parameter $r_{BW}=2.1 +- 0.5 +- 0.5 (GeV/c)^{-1} where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q^{2}=0 (r_{V} = V(0) / A_{1}(0)=1.463 +- 0.017 +- 0.031, r_{2} = A_{2}(0) / A_{1}(0) = 0.801 +- 0.020 +- 0.020) and the value of the axial-vector pole mass parameterizing the q^2 variation of A_{1} and A_{2}: m_{A}=(2.63 +- 0.10 +- 0.13) GeV/c^{2}. The S-wave fraction is equal to ...

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For a better understanding of sulphidation mechanisms, some alloys (alloy 600, alloy 800, Uranus S, iron-chromium-aluminium-alloy) and metals (iron, chromium, nickel, molybdenum, titanium) were tested at 773, 873, 1 073 K in gaseous sulphur dioxide. Total pressure was 760 torrs. Sulphur dioxide pressure was 760, 100 and 10 torrs. Argon, oxygen, water vapor were used, successively, as pressure complement. Oxygen supply, generally speaking cause decay of corrosion resistance in SO/sub 2/ atmospheres especially at 1 073 K with low ratio p/sub O2//P/sub SO/sub 2//. Water vapor supply act similarly. Temperature laws and pressure laws do not give monotonous rise of corrosion values. There are maximas suggesting corrosion products undertaking a volatilization process. According to test conditions, Uranus S, chromium, alloy 800 (and titanium at some extent) showed good corrosion resistance. That results are supporting those ...

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Although experimental results so far agree with predictions of the standard model, it is widely felt to be incomplete. Many prospective theories beyond the standard model predict extra neutral gauge bosons, denoted by Z', which might be light enough to be accessible at the LHC. Observables sensitive to the properties of these extra gauge bosons might be used to discriminate between the different theories beyond the standard model. In the present work several of these observables (total decay width, leptonic cross-section and forward-backward asymmetries) are studied at generation level and with a full simulation in the ATLAS detector. The Z' {yields} e{sup +}e{sup -} decay channel was chosen and 2 values for the mass of Z': 1.5 TeV and 4 TeV. Background is studied as well and it is confirmed that a Z' boson could easily be discovered at the chosen masses. It is shown that even in full ...

CERN Document Server

The $\\phi$(1020) meson leptonic width has been determined from the combined analysis of 4 major decay modes of the resonance ($\\phi\\to K^+ K^-,K^0_LK^0_S,\\pi^+\\pi^-\\pi^0,\\eta\\gamma$) studied with the CMD-2 detector at the VEPP-2M $e^+e^-$ collider. The following value has been obtained: $\\Gamma(\\phi\\to e^+e^-) = 1.235\\pm 0.006\\pm 0.022$ keV. The $\\phi(1020)$ meson parameters in four main decay channels have been also recalculated: $B(\\phi\\to K^+K^-) = 0.493\\pm 0.003\\pm 0.007$, $B(\\phi\\to K_LK_S) = 0.336\\pm 0.002\\pm 0.006$, $B(\\phi\\to\\pi^+\\pi^-\\pi^0) = 0.155\\pm 0.002\\pm 0.005$, $B(\\phi\\to\\eta\\gamma) = 0.0138\\pm 0.0002\\pm 0.0002$.

CERN Document Server

In the presence of the T-parity violating Wess-Zumino-Witten (WZW) anomaly term, the otherwise stable heavy photon A_H in the Littlest Higgs model with T-parity (LHT) decays to either Standard Model (SM) gauge boson pairs, or to SM fermions via loop diagrams. We make a detailed study of the collider signatures where the A_H can be reconstructed from invariant mass peaks in the opposite sign same flavor dilepton or the four-lepton channels. This enables us to obtain information about the fundamental symmetry breaking scale f in the LHT and thereby the low-lying mass spectrum of the theory. In addition, indication of the presence of the WZW term gives us hints of the possible UV completion of the LHT via strong dynamics. The crucial observation is that the sum of all production processes of heavy T-odd quark pairs has a sizeable cross-section at the LHC and these T-odd particles eventually all cascade decay down to the heavy ...

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The deexcitation of quasi-projectiles (QP) released in binary Au on Au collisions as been studied from 60 to 100 MeV/u. Bimodality between two different decay patterns has been observed for intermediate violence collisions. The main experimental result is that the system jumps from one mode to the other on a narrow range of energy deposit and/or impact parameter. The sorting of the events (according to the violence of the collision) has been provided by the perpendicular energy of the light charged particles emitted on the quasi-target side. Such a sorting prevents spurious autocorrelation effects between the sorting variable and the observed mechanism. The two modes of the QP decay correspond on the one side to residue or fission fragments production, and on the other side to the multifragmentation channel. A detailed study has been performed in order to try to establish the origin of the observed bimodality in ...

International Nuclear Information System (INIS)

A series of tests were completed at the Fast Flux Test Facility to demonstrate the passive safety characteristics of liquid metal reactors with natural circulation flow. The first test consisted of transition from forced to natural circulation flow at an initial decay power of 0.3%. The second test represented an unprotected loss-of-flow transient to natural circulation from 50% power with the control rods prevented from scramming into the core. The third test was a steady-state, natural circulation condition with core fission powers up ato about 2.3%. Core sodium data and results of single and multi-channel computer models confirmed the reliability and effectiveness of natural circulation flow for liquid metal reactor safety.

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Resonant inelastic x-ray scattering (RIXS) with soft x-rays is uniquely suited to study the elec-tronic structure of a variety of materials, but is currently limited by low (fluorescence yield) count rates. This limitation is overcome with a new high-transmission spectrometer that allows to measure soft x-ray RIXS"maps." The S L2,3 RIXS map of CdS is discussed and compared with density functional calculations. The map allows the extraction of decay channel-specific"absorp-tion spectra," giving detailed insight into the wave functions of occupied and unoccupied elec-tronic states.

International Nuclear Information System (INIS)

The set of nonlinear equations describing the standard model kinematics of the top quark antiquark production system in the dilepton decay channel has at most a fourfold ambiguity due to two not fully reconstructed neutrinos. Its most precise solution is of major importance for measurements of top quark properties like the top quark mass and tt spin correlations. Simple algebraic operations allow one to transform the nonlinear equations into a system of two polynomial equations with two unknowns. These two polynomials of multidegree eight can in turn be analytically reduced to one polynomial with one unknown by means of resultants. The obtained univariate polynomial is of degree 16. The number of its real solutions is determined analytically by means of Sturm's theorem, which is as well used to isolate each real solution into a unique pairwise disjoint interval. The solutions are polished by seeking the sign change of the polynomial in a given ...

Science.gov (United States)

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CERN Document Server

Neutrinoless Double Beta Decay ($0\

International Nuclear Information System (INIS)

... no. 2) p. 27-28. economics hydrogen power reactors nonmetals (ELEMENTS

Energy Technology Data Exchange (ETDEWEB)

Measurements of the relaxation of the D{sub 2}O stretch mode in vitreous As{sub 2}S{sub 3} are presented. Because the bending mode of the molecule offers an intra-molecular decay channel for the stretch mode, the decay scheme of the D{sub 2}O molecule is more complex than that of diatomic molecules. The asymmetric stretch mode of D{sub 2}O has a frequency of 2680 cm{sup -1}. To study the relaxation of this mode we applied a pump-probe technique, using intense psec; pulses of the Stanford Free Electron Laser. Due to the small cross-section of the vibrational mode, successful efforts were made to improve the signal to noise ratio by using a laser stabilization system and a tightly focused beam to increase the intensity, by averaging the signal with a kHz repetition rate and by using samples with an optimized D{sub 2}O concentration. A rapid relaxation rate on the order of 5 x 10{sup 9} sec{sup -1} at low temperature is found ...

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... coincidence spectrometry decay excited states gamma spectra half-life

International Nuclear Information System (INIS)

... beta decay coincidence spectrometry energy levels energy-level transitions

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The future e{sup +}e{sup -} linear colliders can also operate in the e{gamma} or {gamma}{gamma} modes. In the context of the top-color assisted technicolor (TC2) model, we study the single charged top-pion production process {gamma}{gamma} {yields} tb-bar{pi}{sub t}{sup -}. The results show that the production rates can reach the level of tens fb with reasonable parameter values. So one can expect that enough signals could be produced in future high-energy linear collider experiments. Furthermore, the flavor-changing (FC) decay mode {pi}{sub t}{sup -} {yields} bc-bar is the best channel to detect the charged top pion due to the clean standard model background. With a large number of events and the clean background, the charged top pion should be observable at future linear colliders operating in {gamma}{gamma} mode at the TeV energy scale.

International Nuclear Information System (INIS)

English 2006 2 p. Brazil Rocha, RM Centro Tecnico Aeroespacial, Sao

International Nuclear Information System (INIS)

A diode-laser fluorescence experiment was performed in order to study fine-structure transitions between 5"2P states of rubidium atoms colliding with ground-state potassium or caesium atoms. The Rb(5"2P_3_/_2) state was optically excited and the intensity ratio of sensitized to direct fluorescence was measured. (author).

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Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

The experimental has been performed with a view to studying complete and incomplete fusion in "1"4N + "1"6"3D_y system below 7 MeV/nucleon. The excitation functions for several reactions have been measured using the activation technique and compared with the theoretical predictions based on statistical models. The codes ALICE-91 and CASCADE used earlier for the analysis of excitation functions in case of "1"2C + "1"6"5H_0 system have been used here also with the same set of input parameters. It has been observed that the theoretical calculations do not match with the experimental excitation functions well but the overall shape of the excitation function is reproduced satisfactorily. The composite nucleus ("1"7"7T_a) formed in this ("1"4N + "1"6"3D_y) case is the same as the one formed in "1"2C + "1"6"5H_0 system studied earlier. Measured excitation functions for the same decay channels in the two cases (i.e. "1"2C + "1"6"5H_0 and "1"4N + ...

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The physics and technology of this new Cerenkov detector are discussed, including materials studies, construction techniques, and resolution measurements. Sources of resolution error are individually identified and measured where possible. The results of all studied indicate that the measurement resolution is understood. This work has led to the adoption of a large scale ring imaging detector as part of a new high energy physics spectrometer, the SLD, at the Stanford Linear Accelerator Center. Results from an amplitude analysis of strange meson final states in K/sup /minus//p ..-->.. /ovr K/sub 0//..pi../sup /minus//p interactions are presented. The data derive from a 4 event/nb exposure of the LASS (large Aperture Superconducting Solenoid) spectrometer to an 11 GeV/c K/sup /minus// beam. The data sample consists of /approximately/100,000 vents distributed over the Dalitz plot of the channel. The process is observed to be dominated by the production and ...

International Nuclear Information System (INIS)

Detailed level and decay schemes are presented for the nuclei of the A = 101 mass chain. The level properties obtained from decay and reaction experiments are shown in the drawings. Experimental methods, references, and comments are given in the text.

International Nuclear Information System (INIS)

The electron capture decay scheme of "2"0"3Bi is studied. Energies and relative intensities of gamma rays are given.

CERN Document Server

The existence of n-particle n-hole deformed yrare bands in the N=28 isotones is explored using full pf-shell diagonalizations and the Lanczos Strength Function method. We find different 2p-2h and 4p-4h collective bands that, when allowed to mix, more often disappear. Only the 2p-2h yrare band in Cr-52 and the 4p-4h yrare band in Ni-56 survive, and only in this latter case, due to the reduced density of 2p-2h states, can the band be seen as a gamma-cascade.

International Nuclear Information System (INIS)

(Dec 1971). United States Ryan, MP Jr. v. 68(2) p. 541-555. cosmological

International Nuclear Information System (INIS)

... School of Plant Biology. v. 23(2) p. 316-322. carbon dioxide absorption carbon

International Nuclear Information System (INIS)

English 2004 [2 p.] Brazil Soares, SF Dire, Glaucio Abreu, Paulo Jesus,

UK PubMed Central (United Kingdom)

BackgroundUnderstanding the interactions between ion channels and blockers remains an important goal that has implications for delineating the basic mechanisms of ion channel function...Full Text Available

Science.gov (United States)

Measurement of local steam condensation rates of cocurrent stratified flow of steam and subcooled water was carried out at atmospheric pressure in a horizontal rectangular channel. The channel was constructed of stainless steel with pyrex glass windows, a...

British Library Electronic Table of Contents (United Kingdom)

In this study, the effects of channel surface wettability, cross-sectional geometry and orientation on the two-phase flow in parallel gas channels of proton exchange membrane fuel cells (PEMFCs) are investigated. Ex situ experiments were conducted in flow channels with three different surface wettability (hydrophilically coated, uncoated, and hydrophobically coated), three cross-sectional geometries (rectangular, sinusoidal and trapezoidal), and two orientations (vertical and horizontal). Flow pattern map, individual channel flow variation due to maldistribution, pressure drop and flow visualization images were used to analyze the two-phase flow characteristics. It is found that hydrophilically coated gas channels are advantageous over uncoated or slightly hydrophobic channels regarding un...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Several older and recent reports provided evidence for the oscillatory character of the exponential decay law in radioactive decay and attempted to explain it with basic physics. We show here that the measured effects observed in some of the cases, namely in the decay of {sup 226}Ra, {sup 32}Si in equilibrium, and {sup 36}Cl, can be explained with the temperature variations.

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No abstract prepared.

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International Nuclear Information System (INIS)

Levels in "7"2Se were observed via in-beam gamma spectroscopy following the "5"8Ni("1"6O,2p) reaction. Spectra and partial energy level schemes are shown. (3 figures) (U.S.).

Energy Technology Data Exchange (ETDEWEB)

This thesis contains the candidate's original work on excitonic structure and energy transfer dynamics of two bacterial antenna complexes as studied using spectral hole-burning spectroscopy. The general introduction is divided into two chapters (1 and 2). Chapter 1 provides background material on photosynthesis and bacterial antenna complexes with emphasis on the two bacterial antenna systems related to the thesis research. Chapter 2 reviews the underlying principles and mechanism of persistent nonphotochemical hole-burning (NPHB) spectroscopy. Relevant energy transfer theories are also discussed. Chapters 3 and 4 are papers by the candidate that have been published. Chapter 3 describes the application of NPHB spectroscopy to the Fenna-Matthews-Olson (FMO) complex from the green sulfur bacterium Prosthecochloris aestuarii; emphasis is on determination of the low energy vibrational structure that is important for understanding the energy transfer process associated within three ...

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In this report, I surveyed physics potential of the {gamma}{gamma} option of a linear e{sup +}e{sup -} collider with the following questions in mind: What new discovery can be expected at a {gamma}{gamma} collider in addition to what will be learned at its 'parent' e{sup +}e{sup -} linear collider? By taking account of the hard energy spectrum and polarization of colliding photons, produced by Compton back-scattering of laser light off incoming e{sup -} beams, we find that a {gamma}{gamma} collider is most powerful when new physics appears in the neutral spin-zero channel at an invariant mass below about 80% of the c.m. energy of the colliding e{sup -}e{sup -} system. If a light Higgs boson exists, its properties can be studied in detail, and if its heavier partners or a heavy Higgs boson exists in the above mass range, they may be discovered at a {gamma}{gamma} collider. CP property of the scalar sector can be explored in detail by making use of ...

International Nuclear Information System (INIS)

The paper discusses recent results on the development of localized arc filament plasma actuators and their use in controlling high-speed and high Reynolds number jet flows. Multiple plasma actuators (up to 8) are controlled using a custom-built 8-channel high-voltage pulsed plasma generator. The plasma generator independently controls pulse repetition rate (0-200 kHz), duty cycle and phase for each individual actuator. Current and voltage measurements demonstrated the power consumption of each actuator to be quite low (20 W at 20% duty cycle). Emission spectroscopy temperature measurements in the pulsed arc filament showed rapid temperature increase over the first 10-20 ?s of arc operation, from below 1000 deg. C to up to about 2000 deg. C. At longer discharge pulse durations, 20-100 ?s, the plasma temperature levels off at approximately 2000 deg. C. Modelling calculations using an unsteady, quasi-one-dimensional arc filament model showed that rapid localized ...

British Library Electronic Table of Contents (United Kingdom)

The A2P-X2+Dv=-3 bands of the 12C14N radical have been observed by time-resolved Fourier transform spectroscopy in the 1850-3100cm-1 region with a wavenumber resolution of 0.025cm-1. The radical was produced in a pulsed positive column discharge in a cyanogene and helium mixture. Seven bands of v=0-3, 1-4, 2-5, 3-6, 4-7, 5-8, and 6-9 were analyzed to give the molecular constants of each state by least-squares fitting of 801 lines. The pulsed discharge was found to be efficient for production of CN in the excited A2P state. The vibrational excitation temperature was determined to be 6680+-835K and 6757+-534K for the A2P and X2+ states, respectively. The population of the A2P was found to be 4% of that of the X2+ state in the time after turning off the discharge.

DEFF Research Database (Denmark)

Udgivelsesdato: 2002-May

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To simulate the effects of the breakup channel on rearrangement amplitudes, the conventional coupled-reaction-channel (CRC) expansion is augmented by pseudoreaction channels. The construction of the projector for the extended CRC space is discussed, and transition-operator equations on this space are given. By solving the full and post-approximation forms of the CRC equations for a model three-particle problem, the crucial role played by the nonorthogonality terms is demonstrated.

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Science.gov (United States)

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International Nuclear Information System (INIS)

Short note.

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DEFF Research Database (Denmark)

Udgivelsesdato: 2009

International Nuclear Information System (INIS)

Applying diode-laser resonant fluorescence method, the cross sections for the excitation energy transfer of the collisional process K"*(4"2P_1_/_2)+Cs(6"2S_1_/_2)#reversible#K"*(4"2P_3_/_2)+Cs(6"2S_1_/_2) have been measured. The values we have obtained are #sigma#(1/2#->#3/2)=77 A"2 and #sigma#(3/2#->#1/2)=48 A"2. These results complete the sequence of data for the fine-structure mixing of the first-resonance states of alkali atoms colliding with the ground-state caesium atoms. (orig.).

Energy Technology Data Exchange (ETDEWEB)

In the development of high performance heat transfer surface on a compact heat exchanger, it was clarified that how reattachment point heat transfer and fluid flow are affected by channel width, at the same time, an evaluation of heat transfer performance and an investigation of optimum channel width were carried out. The channel system used in the experiment is as follows; (1) blow-off type with rectangular section channel, (2) span length of 200 mm, (3) wave length (pitch) of 80 mm, and (4) channel length of 12.5 wave length. The channel Reynolds number was set at about 10/sup 4/ which is relatively higher than the current studies. The results of the experiment were summarized as follows. (1) The channel width H has relevance to the phase difference between the fluid flow in cone portion of main stream and wave shape, the flow patterns are ...

CERN Document Server

Experimental studies of charmless semileptonic B decays can be broadly categorized into inclusive and exclusive measurements depending on how the final states are treated. The inclusive method measures the decay rate $\\Gamma(B \\to X_u \\ell \

Energy Technology Data Exchange (ETDEWEB)

Detailed level and decay schemes and the experimental reaction and decay data on which they are based are presented for nuclei with mass number A = 242; the experimental data are evaluated. Adopted values for level and ..gamma..-ray energies, ..gamma..-intensities, as well as other nuclear properties are given.

CERN Document Server

We give a summary of the discussions in Working Group V of the CKM2010 workshop dealing with determinations of the angle gamma of the unitarity triangle of the Cabibbo-Kobayashi-Maskawa matrix from B-meson decays into charmed final states.

British Library Electronic Table of Contents (United Kingdom)

This paper introduces briefly neutrinoless Double Beta Decay and discusses its implications for neutrino physics. After a presentation of general experimental concepts, such as the various proposed methodological approaches and the sensitivity, the current experimental situation is concisely reviewed.

International Nuclear Information System (INIS)

... bismuth 203 chemical reactions cyclotrons decay helium 3 beams impurities

Science.gov (United States)

It is shown that there may be a correlation between the galactic cosmic rays and the solar neutrino

International Nuclear Information System (INIS)

The measurements of the nuclear decay of actinide isotopes and the evaluation of the radioactive properties of nuclide with the mass 242 is discussed in this paper.

International Nuclear Information System (INIS)

... comparative evaluations energy-level transitions half-life internal conversion

CERN Document Server

The absolute branching fractions for the decays $D^0 \\to K^-e ^+\

International Nuclear Information System (INIS)

Gamma-rays and conversion electrons emitted in the "1"1"7Cs and "1"1"7Xe decays have been studied from on-line mass-separated "1"1"7Cs sources at the ISOLDE facility. A new "1"1"7Xe decay scheme has been constructed and a level scheme has been established for the "1"1"7Cs decay. The results are discussed in the frame of our recent knowledge about odd-mass neutron-deficient I and Xe systematics.

CERN Document Server

LHC$b$ is one the four major experiments at the Large Hadron Collider (LHC) at CERN. It is custom built to look for CP violation and New Physics in rare decays of heavy flavor hadrons, like the B and D systems. Rare decays that occur via loop diagrams provide a way to probe New Physics at energy scales much higher than can be probed by direct production in experiment. In this article, the LHC$b$ prospects for such measurement with exclusive decays of the type $B \\to X_s\\gamma$ and $B\\to X_sl^+l^-$ are presented.

International Nuclear Information System (INIS)

... angiotensin gallium 67 lungs lysozyme patients sarcomas beta decay

Science.gov (United States)

The local heat transfer coefficient distribution of a square channel with two opposite ribbed walls was determined. The square channel was connected to a sudden contraction entrance in order to simulate the inlet condition of the turbine blade cooling passages. The test channel was heated by thin stainless steel foils with a thickness of 0.000025 m, and instrumented with 180 thermocouples. The brass ribs of a square cross-section were glued periodically, in line, onto the top and bottom walls of the foil-heated channel in patterns to achieve the desired spacing and angle-of-attack. The local heat transfer coefficients on the smooth side and the ribbed side walls, at the channel entrance and the downstream regions, were measured for eight rib configurations and three Reynolds numbers (Re = 10,000, 30,000, and 60,000).

UK PubMed Central (United Kingdom)

Genomic disorders are conditions that result from DNA rearrangements, such as deletions or duplications. The identification of the dosage-sensitive gene(s) within the rearranged genomic interval is...Full Text Available

Science.gov (United States)

Two manufacturing processes have been developed for fabricating PLZT bonded lens assemblies (BLA's) for the USAF EEU-2/P Thermal/Flash Protective Goggle. One process utilizes thin Sylgard spacers which remain in the BLA to establish bond thickness between...

UK PubMed Central (United Kingdom)

AimsThe experiments explored for atrial arrhythmogenesis and its possible physiological background in recently developed hetero-(RyR2^+/S) and homozygotic...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The nucleon decay of subbarrier single-particle states with large angular momentum and parity opposite to that of the shell in soft spherical nuclei is considered. It is shown that the reduced probabilities of the nucleon decay into the ground state (0{sup +}) and into the first excited (2{sup +}) state of the daughter nucleus have qualitatively different energy dependences. (orig.).

International Nuclear Information System (INIS)

Nucleon decay of underbarrier one-quasiparticle states with large angular momentum in soft spherical nuclei is considered. It is shown that energy dependences of differential probabilities of nucleon decay to the ground (0"+) and first excited (2"+) states of daughter nucleus differ qualitatively from each other due to strong interaction between quasiparticles and low-lying quadrupole states.

International Nuclear Information System (INIS)

New measurements of relative gamma-ray emission probabilities in the decay of "1"0"1Mo and "1"0"1Tc are reported. Previously published conversion-electron data have been used along with the gamma-ray data to formulate self-consistent decay schemes. (orig.).

Energy Technology Data Exchange (ETDEWEB)

The calculations of the photodetachment cross section for the C{sup -} negative ion has been performed within the newly-developed many-body theory method, the RPAE interchannel interaction and dynamic relaxation and polarization corrections being included. The 2s{sup 1}2p{sup 4} shape resonance is shifted to a higher photon energy and broadens as compared to the resonance parameters determined earlier within the RPAE, which is consistent with the experimental evidence and the recent R-matrix calculations. (orig.) 18 refs.

Energy Technology Data Exchange (ETDEWEB)

The first analysis of inelastic J/{psi} meson production in photoproduction (Q{sup 2}<2.5 GeV{sup 2}) of the H1 experiment for the second phase of HERA (HERA II) is presented. The analysis is carried out at low and medium elasticities. The production of heavy quarks (charm, or bottom) is of special interest since the mass of the quarks provides a hard scale for the application of perturbative QCD. The muonic decay channel is used to select the J/{psi} mesons. The data was collected by the H1 detector during the period 2003-2005, and corresponds to an integrated luminosity of 133 pb{sup -1}. However only a subset of this data could be analysed. At the start of HERA II the trigger system was affected by a sizeable background. Then a fault was introduced in the trigger software during the summer 2004 and was only discovered and solved in April 2006. This means that approximately 80 % of the triggered events at medium elasticities and 65 % ...

International Nuclear Information System (INIS)

Interleukin 2 (IL-2) is a T-cell-derived lymphokine critical in the activation and proliferation of T cells, B cells, and lymphokine-activated killer cells. It is a glycoprotein of #approx#15,500 daltons that is synthesized and secreted after activation by antigen or mitogen. By using the analogs 8-azidoadensoine 5'-[#gamma#-"3"2P]triphosphate ([#gamma#-"3"2P]8N_3ATP) and nicotinamide 2-azidoadenine [adenylate-"3"2P]dinucleotide ([#alpha#-"3"2P]2N_3NAD"+) as photoaffinity probes, the authors have detected specific, metal ion-requiring nucleotide binding sites on recombinant human IL-2 (rhIL-2). The specificity of these nucleotide interactions with rhIL-2 was demonstrated by saturation effects and by competition by the parent nucleotides at physiologically relevant concentrations. Saturation of photoinsertion into rhIL-2 ...

UK PubMed Central (United Kingdom)

SUMMARYIn voltage-gated sodium, potassium, and calcium channels the functions of ion conduction and voltage sensing are performed by two distinct structural units: the pore domain...Full Text Available

UK PubMed Central (United Kingdom)

SummaryTRPV1 is the founding and best-studied member of the family of temperature-activated transient receptor potential ion channels (thermoTRPs). Voltage, chemicals, and heat...Full Text Available

UK PubMed Central (United Kingdom)

We have used the two-electrode voltage clamp technique and the patch clamp technique to investigate the regulation of ROMK1 channels by protein-tyrosine phosphatase (PTP) and protein-tyrosine...Full Text Available

UK PubMed Central (United Kingdom)

Searching for the structural requirements improving the potency and the stereoselectivity of Na⁺ channel blockers as antimyotonic agents, new...Full Text Available

UK PubMed Central (United Kingdom)

We analyze transport through conical channels due to the difference in particle concentration on the two sides of the membrane. Because of the detailed balance, fluxes of non-interacting particles...Full Text Available

UK PubMed Central (United Kingdom)

In voltage-gated Na⁺, K⁺, and Ca²⁺ channels, four voltage-sensor domains operate on a central pore domain in response to membrane voltage. In contrast, the voltage-gated...Full Text Available

CERN Document Server

Consider the simultaneous relay channel which consists of a set of relay channels where the source wishes to transmit common and private information to each of the destinations. This problem is recognized as being equivalent to that of sending common and private information to several destinations in presence of helper relays where each channel outcome becomes a branch of the broadcast relay channel (BRC). Cooperative schemes and capacity region for a set of two relay channels are investigated. The proposed coding schemes, based on Decode-and-Forward (DF) and Compress-and-Forward (CF), must be capable of transmitting information simultaneously to all destinations in such set. Inner bounds on the capacity region of the general BRC are based on three cases. First the channels from source-to-relays of both destinations are assumed to be stronger than the others and ...

UK PubMed Central (United Kingdom)

Recent studies suggest that calcium influx via L-type calcium channels is necessary for psychostimulant-induced behavioral sensitization. In addition, chronic amphetamine upregulates subtype...Full Text Available

UK PubMed Central (United Kingdom)

T-type calcium channels are responsible for generating low-threshold spikes that facilitate burst firing and neurotransmitter release in neurons. GnRH neurons exhibit burst firing, but the underlying...Full Text Available

International Nuclear Information System (INIS)

The #gamma# rays following the #beta# decays of "8"8Kr and "8"8Rb have been studied, using both large volume Ge(Li) detectors for singles and coincidence measurements and anti-Compton spectrometry for singles measurements. Level schemes for "8"8Rb and "8"8Sr were constructed from the data and 74 of 81 #gamma# rays observed in the decay of "8"8Kr were placed in the "8"8Rb level scheme with 23 excited states. For the decay of "8"8Rb, all of the observed 27 #gamma# rays have been placed in the (well known) level structure of "8"8Sr. Spin and parity assignments have been deduced from #beta#-decay logft values and #gamma#-ray transition patterns. Possible shell model interpretations are presented for the level schemes.

Science.gov (United States)

... table (ASCAMP) system and the Military Strategic and Tactical Relay (Milstar) program. 10 ... Single Channel Antijam Milstar Portable Terminal ...

International Nuclear Information System (INIS)

... mixing coupled channel theory differential cross sections excited states helium

Science.gov (United States)

... measurement. Power spectral density measurements are made by the dynamic signal analyzer for each channel. A cross power ...

International Nuclear Information System (INIS)

Nuclear structure information for all nuclei with mass number A = 216 is summarized. Evaluated data and the adopted levels and spin and parity assignments are given. Only the #alpha#-decay mode has been observed for all nuclei in this mass chain. Possible epsilon-capture and/or #beta#-decay are expected to be quite weak for most of them. An upper limit of 0.6 percent was set by 68Va18 for "2"1"6Th epsilon-decay from #alpha#-yields. The compilers estimate any epsilon-capture decay from "2"1"6At to "2"1"6Po to be less than 1.5 x 10"-"6 percent; similarly, #beta#-decay from "2"1"6At to "2"1"6Rn ground state is expected to be less than 0.0004 percent, and allowed #beta#"- to any yet unobserved level in "2"1"6Rn can be estimated to be less than 0.005 percent from expected log ft values. Level scheme information for all nuclei is from #alpha#-decays of their parents ...

UK PubMed Central (United Kingdom)

Inhibition of large conductance calcium-activated potassium (BK_Ca) channels mediates, in part, oxygen sensing by carotid body type I cells. However, BK_Ca channels remain active...Full Text Available

CERN Document Server

A Multi-Channel Algebraic Scattering (MCAS) theory is presented with which the properties of a compound nucleus are found from a coupled-channel problem. The method defines both the bound states and resonances of the compound nucleus, even if the compound nucleus is particle unstable. All resonances of the system are found no matter how weak and/or narrow. Spectra of mass-7 nuclei and of {}^{15}F, and MCAS results for a radiative capture cross section are presented.

UK PubMed Central (United Kingdom)

Vacuolar ion channels in guard cells play important roles during stomatal movement and are regulated by many factors including Ca²⁺, calmodulin, protein kinases, and phosphatases....Full Text Available

International Nuclear Information System (INIS)

Planar channeling effects are studied in such well-oriented polycrystalline layers as NiSi_2 and Pb_2Si layers formed on single crystalline Si. Crystalline perfection of such layers is discussed by using the energy- and angular dependences of the axial and planar channeling yields. It has been shown that, in suitable conditions, the energy dependence of the planar yield is more sensitive to the spread of crystallite orientations in polycrystals than that of the axial one. (Auth.).

International Nuclear Information System (INIS)

This paper evaluates the electric current terms from the longitudinal gradient of the longitudinal electric field in Bipolar Field-Effect-Transistors (BiFETs) with a pure base and two MOS gates operating in the unipolar (electron) current mode. These nMOS-BiFETs, known as nMOS-FinFETs, usually have electrically short channels compared with their intrinsic Debye length of about 25 #mu#m at room temperatures. These longitudinal electric current terms are important short-channel current components, which have been neglected in the computation of the long-channel electrical characteristics. This paper shows that the long-channel electrical characteristics are substantially modified by the longitudinal electrical current terms when the physical channel length is less than 100 nm.

British Library Electronic Table of Contents (United Kingdom)

The investigation of steam, water, and air flow characteristics in horizontal channel is a part of major investigations program at the Lithuanian Energy Institute. The objective of this program is to identify condensation effects on two-phase flow stability and to predict conditions when rapid condensation could be induced in two-phase condensable flow. This article presents investigation of steam-water and air multiphase flow in nearly horizontal rectangular channel. The experimental data for pressure drop and interfacial and wall shear stresses in the channel with uniform distribution of void fraction are presented in this paper. Overall channel dimensions are length = 1.2 m, width = 0.02 m, height = 0.1 m; however, the test section was about 0.84 m in length. Three different flow types ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Sudden infant death syndrome (SIDS) is always a devastating and unexpected occurrence. SIDS is the leading cause of death in the first 6 months after birth in the industrialized world. Since the discovery in 1998 of long QT syndrome as an underlying substrate for SIDS, around 10-20% of SIDS cases have been proposed as being caused by genetic variants in either ion channel or ion channel-associated proteins. Until now, 10 cardiac channelopathy susceptibility genes have been found to be implicated in the pathogenesis of SIDS. Four of the genes encode cardiac ion channel a-subunits, 3 genes encode ion channel b-subunits, and 3 genes encode other channel-interacting proteins. All 10 genes have been associated with primary electrical heart diseases. SIDS may hereby be the initial sympt...

International Nuclear Information System (INIS)

Previous flow regime studies have been for horizontal, vertical, and inclined pipe flow. As such, only a few studies have been performed on bundle geometries. The present paper examines the flow regimes for a vertical hexagonal flow channel with and without a finned fuel bundle. This type of a 36 finned rod hexagonal fuel bundle in parallel hexagonal flow channels is used in a MAPLE (Multi- purpose Applied Physics Lattice Experimental) type nuclear reactor. An experiment apparatus was designed consisting of the flow channel, inlet plenum and an air-water separator. The inlet plenum is used to provide a uniform mixture of air and water before entering the hexagonal flow channel. A turbine flow meter is used to determine the water flow rate. The turbine flow meter is calibrated for a low flow range and limits the measurable flow to 50 l/min. Flow pattern observation is determined by a SONY video camera, ...

International Nuclear Information System (INIS)

TAPP-3 and 4 are the 540 MWe PHWRs having horizontal fuel channel. At normal 100% FP operation there is no boiling in the channel. However, when the power increases due to any transient, the boiling may start in the channel. The main application for critical heat flux (CHP) prediction is to set the operating power with a comfortable margin to avoid CHF occurrence. This margin of CHF can be expressed in terms of minimum critical heat flux ratio (MCHFR), which is the ratio of CHF to local heat flux for the same pressure, mass flux and quality. The CHF depends on power, coolant flow rate as well as coolant condition in the channel. As the power increases the flow reduces in the channel and cooling is degraded. The thermal hydraulic code is developed for present analysis. The output of analysis are CHF prediction quality calculation at axial locations of the maximum rated ...

International Nuclear Information System (INIS)

Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10"6n/cm"2-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,#integral#dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, and ...

CERN Document Server

Recent observations of a large excess of cosmic-ray positrons at high energies have raised a lot of interest in leptonic decay modes of dark matter particles. Nevertheless, dark matter particles in the Milky Way halo could also decay hadronically, producing not only a flux of antiprotons but also a flux of antideuterons. We show that for certain choices of parameters the antideuteron flux from dark matter decay can be much larger than the purely secondary flux from spallation of cosmic rays on the interstellar medium, while the total antiproton flux remains consistent with present observations. We show that if the dark matter particle is sufficiently light, the antideuteron flux from dark matter decay could even be within the reach of planned experiments such as AMS-02 or GAPS. Furthermore, we discuss the prospects to observe the antideuteron flux in the near future if the steep rise in the positron ...

CERN Document Server

We show that to explain the growth of the citation network by preferential attachment (PA), one has to accept that individual nodes exhibit heterogeneous fitness values that decay with time. While previous PA-based models assumed either heterogeneity or decay in isolation, we propose a simple analytically treatable model that combines these two factors. Depending on the input assumptions, the resulting degree distribution shows an exponential, log-normal or power-law decay, which makes the model an apt candidate for modeling a wide range of real systems.

Energy Technology Data Exchange (ETDEWEB)

Decay sequences based on the 1/2/sup +/(660) proton orbital have been identified in /sup 171/Ta and /sup 177/Re based on spin, parity, and large alignment. This decay sequence is observed higher in energy than predicted in cranking calculations based on modified oscillator potentials. Similarly known 1/2/sup -/(541) decay sequences in these and other neighbouring isotopes are observed lower in energy than predicted. A reduction in the strength of the spin-orbit potential for protons is suggested as a solution to these problem.

International Nuclear Information System (INIS)

Electron elastic and collisional excitation cross sections from the ground state of potassium are calculated using the noniterative integral-equation method of Henry, Rountree, and Smith [Comput. Phys. Commun. 23, 233 (1981)] in the electron energy range 4#<=#E#<=#200 eV. Configuration-interaction target wave functions that take account of correlation and polarization effects are used to represent the ground state and the six lowest excited states 4p "2P degree, 5s "2S, 3d "2D, 5p "2P degree, 4d "2D, and 6s "2S. Elastic and discrete excitation cross sections are obtained in a seven-state close-coupling (7CC) approximation. The 7CC elastic and excitation cross sections are compared and contrasted. Near threshold the elastic cross section dominates the resonance, 4s "2S#->#4p "2P degree, and the sum of the other remaining excitation cross sections. ...

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow in horizontal parallel channels has been experimentally investigated under fuel cell related operating conditions. Pronounced hysteresis is observed in the pressure drop versus flow characteristic curve when starting from either flooded or dry conditions. When gas is introduced into channels initially filled with water (flooded initial condition), both gas and liquid tend to flow predominantly in one channel at low gas or liquid flow velocities. As the gas flow velocity increases, even distribution of gas and liquid flow in both channels is observed, accompanied with a sudden decrease in the pressure drop. On the other hand, even gas and liquid flow distribution between both channels is found at comparatively lower gas flow velocities when starting with dry-gas flow conditions with liquid introduced into channels filled with gas (stratified flow ...

CERN Document Server

The near-threshold enhancement in the ppbar invariant mass spectrum from the B^+ -> K^+ ppbar decay reported recently by the BaBar Collaboration is studied within the J\\"ulich NNbar model. We illustrate that the invariant mass dependence of the ppbar spectrum close to the threshold can be reproduced by the final state interactions. This explanation is in line with our previous analysis of the ppbar invariant mass spectrum from the J/Psi -> gamma ppbar decay measured by the BES Collaboration. We also comment on a structure found recently in the pi^+ pi^- eta' mass spectrum of the radiative J/Psi decay by the BES Collaboration. In particular we argue that one should be rather cautions in bringing this structure in connection with the enhancement found in the ppbar invariant mass spectrum or with the existence of NNbar bound states.

International Nuclear Information System (INIS)

German 2001 p. 253-258 Germany Hages, P. Stratmann, W. STEAG encotec

International Nuclear Information System (INIS)

The decay of mass-separated samples of the previously unknown nuclide "7"1Br have been investigated by means of the Chalk River on-line isotope separator. Eleven #gamma#-transitions were assigned to the decay of this nuclide and its half-life was measured to be 21.4 +- 0.6 s. A simple decay scheme for "7"1Br has been constructed incorporating six levels in its daughter, "7"1Se. The half-life of the first excited state in "7"1Se was measured to be 5.5 +- 1.0 #mu#s and the transition from this state to the ground state was found to be highly converted. Systematic trends in the level schemes of "6"7Zn, "6"9Ge and "7"1Se are investigated. (orig.).

Energy Technology Data Exchange (ETDEWEB)

In April and May of 1999 the Berkeley Gas-filled Separator was used to search for the production and decay of element 118 from the {sup 86}Kr + {sup 208}Pb reaction, according to Smolanczuk's predictions of relatively large production rates. Three decay chains, each consisting of an implanted heavy ion, followed by a rapid (ms) succession of high-energy (>10 MeV) alpha-particle decays were detected. These chains are consistent with the production and decay of element 118 with mass number 293. These results a) show experimental evidence for the existence of shell-stabilized superheavy elements, b) provide experimental values for refinement of nuclear mass models in the superheavy element region, and, most importantly, c) present a new' reaction pathway for the production of superheavy elements. (author)

CERN Document Server

We report a measurement of the branching fractions for $B^{0} \\rightarrow \\pi^- \\ell^+\

Energy Technology Data Exchange (ETDEWEB)

The authors present the results of a search for W{prime} boson decaying to electron-neutrino pairs in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using a data sample corresponding to 205 pb{sup -1} of integrated luminosity collected by the CDF II detector at Fermilab. They observe no evidence for this decay mode and set limits on the production cross section times branching fraction, assuming the neutrinos from W{prime} boson decays to be light. If they assume the manifest left-right symmetric model, they exclude a W{prime} boson with mass less than 788 GeV/c{sup 2} at the 95% confidence level.

Energy Technology Data Exchange (ETDEWEB)

We study CP-violating phenomena in the production, mixing and decay of a coupled system of CP-violating neutral Higgs bosons at {gamma}{gamma} colliders, assuming a Minimal Supersymmetric Standard Model (MSSM) Higgs sector in which CP violation is radiatively induced by phases in the soft supersymmetry-breaking gaugino masses and third-generation trilinear squark couplings. We discuss CP asymmetries in the production and decays of {mu}{sup +}{mu}{sup -}, {tau}{sup +}{tau}{sup -}, b-bar b and t-bar t pairs. We find large asymmetries when two (or all three) neutral Higgs bosons are nearly degenerate with mass differences comparable to their decay widths, as happens naturally in the CP-violating MSSM for values of tan{beta}-bar 5 (30) and large (small) charged Higgs-boson masses.

Energy Technology Data Exchange (ETDEWEB)

The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and ...

International Nuclear Information System (INIS)

The available nuclear structure information for all nuclei with mass number A=242 is presented. Various decay and reaction data are evaluated. Adopted data, levels, spin and parity assignments are given.

Energy Technology Data Exchange (ETDEWEB)

This report discusses the following topics: study of Z{sup 0} decays; QCD; new particles; Higgs bosons; and forward hadron calorimeter system.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

... 45 p. absorption spectroscopy errors lead lead 203 beta decay radioisotopes

Energy Technology Data Exchange (ETDEWEB)

In the context of safety assessment of radioactive waste repositories, complex radionuclide transport models covering key safety-relevant processes play a major role. In recent Swiss safety assessments, such as Kristallin-I, an important drawback was the limitation in geosphere modelling capability to account for geosphere heterogeneities. In marked contrast to this limitation in modelling capabilities, great effort has been put into investigating the heterogeneity of the geosphere as it impacts on hydrology. Structural geological methods have been used to look at the geometry of the flow paths on a small scale and the diffusion and sorption properties of different rock materials have been investigated. This huge amount of information could however be only partially applied in geosphere transport modelling. To make use of these investigations the 'PICNIC project' was established as a joint cooperation of PSI/Nagra and QuantiSci to provide a new geosphere transport ...

Energy Technology Data Exchange (ETDEWEB)

The portion of the potential energy surface (PES) of acetylacetone relevant for the intramolecular proton transfer reaction is studied using ab initio and DFT methods. The best estimate of the barrier governing proton transfer was found to be 3.4 kcal mol{sup -1} at the MP4(FC)/6-311 + G(2d,2p)//MP2(FC)/6-311 + G(2d,2p) level of theory. Six stationary points on the PES were characterized as well as the reaction paths connecting these points. Special attention paid to the pathway of intramolecular proton transfer reveals that the internal rotation of the methyl group adjacent to the carbonyl group and the proton transfer reaction are consecutive processes.

CERN Document Server

This work presents accurate ab initio determination of the hyperfine splitting for the ground state and few low-lying excited states of 113Cd+; important candidates for the frequency standard in the microwave region, using coupled-cluster theory (CC) in the relativistic framework. The calculated hyperfine splitting are well in agreement with recent experimental results. We have also carried out the lifetimes of the 5p2P1=2 and 5p2P3=2 states, which are in well agreement with recent experimental result (Moehring et al., PRA 73 023413, 2006). The roles of different electron correlation effects in the determination of these quantities are discussed and their contributions are presented in the CC terms.

CERN Document Server

We consider a noisy Slepian-Wolf problem where two correlated sources are separately encoded and transmitted over two independent binary memoryless symmetric channels. Each channel capacity is assumed to be characterized by a single parameter which is not known at the transmitter. The receiver has knowledge of both the source correlation and the channel parameters. We call a system universal if it retains near-capacity performance without channel knowledge at the transmitter. Kudekar et al. recently showed that terminated low-density parity-check (LDPC) convolutional codes (a.k.a. spatially-coupled LDPC ensembles) can have belief-propagation thresholds that approach their maximum a-posteriori thresholds. This was proven for binary erasure channels and shown empirically for binary memoryless symmetric channels. They also conjectured that the principle of spatial ...

Energy Technology Data Exchange (ETDEWEB)

Crystallography and computer modeling have been used to exploit a previously unexplored channel in the glucocorticoid receptor (GR). Highly potent, nonsteroidal indazole amides showing excellent complementarity to the channel were designed with the assistance of the computational technique AlleGrow. The accuracy of the design process was demonstrated through crystallographic structural determination of the GR ligand-binding domain-agonist complex of the D-prolinamide derivative 11. The utility of the channel was further exemplified through the design of a potent phenylindazole in which structural motifs, seen to interact with the traditional GR ligand pocket, were abandoned and replaced by interactions within the new channel. Occupation of the channel was confirmed with a second GR crystal structure of this truncated D-alaninamide derivative 13. Compound 11 displays properties ...

Energy Technology Data Exchange (ETDEWEB)

To investigate the influence of equal channel angular pressing on the microstructure and texture of the magnesium alloy AZ31, electron backscattering diffraction and well as neutron diffraction experiments were carried out. Through these experiments it was possible to trace the microstructure and texture evolution with strain accumulated with the increasing number of equal channel angular pressing passes. It was further demonstrated by subsequent compression tests that the microstructural changes produced by equal channel angular pressing have a beneficial effect on both the compressive strength and ductility of AZ31. (orig.)

Science.gov (United States)

Lanthanide-ion doped oxide nanoparticles were functionalized for use as fluorescent biological labels. These nanoparticles are synthesized directly in water which facilitates their functionalization, and are very photostable without emission intermittency. Nanoparticles functionalized with guanidinium groups act as artificial toxins and specifically target sodium channels. They are individually detectable in cardiac myocytes, revealing a heterogeneous distribution of sodium channels. Functionalized oxide nanoparticles appear as a novel tool particularly well adapted to long-term single-molecule tracking.

International Nuclear Information System (INIS)

Cross sections for the elastic and inelastic scattering of "1"6O on "5"8Ni, "8"8Sr, "4"0Ca, and "4"8Ca have been calculated in a coupled-channels treatment, including the low-lying 2"+ and 3"- states of both projectile and target. Real, energy-independent ion-ion potentials and form factors were used, and fusion was simulated by ingoing wave boundary conditions in all channels. The agreement with the measured scattering data is qualitatively as good as obtained in previous optical-model calculations.

CERN Document Server

This paper focuses on the analysis of average Gaussian error probabilities in certain fading channels, i.e. we are interested in E[Q((p {\\gamma})^(1/2))] where Q(.) is the Gaussian Q-function, p is a positive real number and {\\gamma} is a nonnegative random variable. We present a unified analysis of the average Gaussian error probability, derive a compact expression in terms of the Lauricella FD^(n) function that is applicable to a broad class of fading channels, and discuss the relation of this expression and expressions of this type recently appeared in literature. As an intermediate step in our derivations, we also obtain a compact expression for the outage probability of the same class of fading channels. Finally, we show how this unified analysis allows us to obtain novel performance analytical results.

International Nuclear Information System (INIS)

The ROP margin in a CANDU reactor is decreasing over time due to the Primary Heat-Transport System (PHTS) aging effect. Adjustment of the ROP trip setpoint is required to maintain a high trip-probability and ROP trip effectiveness. Especially, for Wolsong-1, which is scheduled to change the old pressure tubes in 2009, the trend of ROPT after the retubing should be reevaluated. Before setting a ROPT, the main thermal characteristics including Critical Channel Power (CCP) should be calculated by the NUCIRC code. In this paper, the thermalhydraulic evaluation for Wolsung-1 was conducted with the updated Wolsung-1 PHTS data. Specifically, for the case of 0 EFPY (Effective Full Power Year) and 11 EFPY after the retubing, the distribution of the channel flow rate, channel exit quality, critical channel power, and critical power ratio (CPR) of the Wolsong-1 aged plant are calculated

Science.gov (United States)

We propose a quantum secure direct communication scheme based on non-orthogonal entangled pairs and local measurement. In this scheme, we use eight non-orthogonal entangled pairs to act as quantum channels. Due to the non-orthogonality of the quantum channels, the present protocol can availably prohibit from all kinds of valid eavesdropping and acquire a secure quantum channel. By local measurement, the sender acquires a secret random sequence. The process of encoding on the random sequence is identical to the one in one-time-pad. So the present protocol is secure. Even for a highly lossy channel, our scheme is also valid. The scheme is feasible with present-day techniques.

UK PubMed Central (United Kingdom)

Within the cardiac cell, the movements of calcium ions are tightly regulated by a number of regulatory proteins including pumps, and channels. The sarcoplasmic reticulum (SR) is in large part...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This report describes all time and frequency analysis parameters measured with the new Nuclear Weapons Identification System (NWIS) processor with three input channels: (1) the {sup 252}Cf source ionization chamber; (2) a detection channel; and (3) a second detection channel for active measurements. An intuitive and physical description of the various functions is given as well as a brief mathematical description and a brief description of how the data are acquired. If the full five channel capability is used, the number of functions increases in number but not in type. The parameters provided by this new NWIS processor can be divided into two general classes: time analysis signatures including multiplicities and frequency analysis signatures. Data from measurements with an 18.75 kg highly enriched uranium (93.2 wt%, {sup 235}U) metal casting for storage are presented to illustrate the various time and ...

Science.gov (United States)

A method for calculating flow through an airfoil cascade drawn on a surface of revolution is discussed. The three-dimensional flow was assumed to be represented by part-channels of varying width. The basic equations are the equation of continuity and the ...

Science.gov (United States)

... JTIDS) LPC-10 voice channel has been an important facet of a larger ongoing in-house research task on Digital Audio Technology for Aircraft ...

Science.gov (United States)

... thus can function as switches -6 ... Akkari, "Optical Channel Waveguide Switch and Coupler ... Wide-Band Guided Wave Acousto-Optic Bragg Diffraction ...

Energy Technology Data Exchange (ETDEWEB)

Experiments on heat transfer augmentation in a rectangular cross-section water channel are reported. The channel geometry is designed to excite normally damped Tollmein-Schlichting modes in order to enhance mixing. In this experiment, a hydrodynamically fully developed flow encounters a test section where one channel boundary is a series of periodic, saw-tooth, transverse grooves. Free shear layers span the groove openings, separating the main channel flow from the circulating vortices contained within each cavity. The periodicity length of the grooves is equal to one-half of the expected wavelength of the most unstable mode. The remaining channel walls are flat, and the channel has an aspect ratio of 10:1. Experiments are performed over the Reynolds number range of 300 to 15,000. Streakline flow visualization shows that the flow is steady at the entrance, but ...

Science.gov (United States)

of a stochastic network can be a. PERT-type network. After the terminal countdown, ...... pictorial representation of a single channel queueing system ...

British Library Electronic Table of Contents (United Kingdom)

Mixed convection heat transfer from longitudinal fins inside a horizontal channel has been investigated for a wide range of modified Rayleigh numbers and different fin heights and spacings. An experimental parametric study was made to investigate effects of fin spacing, fin height and magnitude of heat flux on mixed convection heat transfer from rectangular fin arrays heated from below in a horizontal channel. The optimum fin spacing to obtain maximum heat transfer has also been investigated. During the experiments constant heat flux boundary condition was realized and air was used as the working fluid. The velocity of fluid entering channel was kept nearly constant (0.15win0.16m/s) using a flow rate control valve so that Reynolds number was always about Re=1500. Experiments were conducted...

Science.gov (United States)

... time. The Paleozoic Era ended only 248 million years ago, the Mesozoic Era ended only 65 million years ago, and so on. ...

International Nuclear Information System (INIS)

During the last two decades, the demand for higher heat transfers in the heat exchangers has kept increasing. These high heat transfer rates can be obtained by using two-phase flows, or heat transfer augmented surfaces, or in some cases, both. Thus, the boiling flows and the associated two-phase flow instabilities have been studied by many investigators. Most of the work in boiling flows has been concentrated on single channel upflow systems or on parallel channel systems with plain heat transfer surfaces. The boiling flow instabilities in multi-channel systems should be covered to a greater extent, studying the effects of various parameters, such as inlet and outlet restriction, mass flow rates, the property variations, heat transfer coefficients, equal and unequal heat inputs on the stability. Also, the mathematical modeling needs to be developed for the parallel channel system to take into account ...

CERN Document Server

We consider a multiple-input multiple-output (MIMO) multiple access channel (MAC), where the channel between each transmitter and the receiver is modeled by the doubly-scattering channel model. Based on novel techniques from random matrix theory, we derive deterministic approximations of the mutual information, the signal-to-noise-plus-interference-ratio (SINR) at the output of the minimum-mean-square-error (MMSE) detector and the sum-rate with MMSE detection which are almost surely tight in the large system limit. Moreover, we derive the asymptotically optimal transmit covariance matrices. Our simulation results show that the asymptotic analysis provides very close approximations for realistic system dimensions.

International Nuclear Information System (INIS)

A two-phase flow regime map is developed experimentally and theoretically for a vertical hexagonal flow channel with and without a 36-finned rod hexagonal bundle. This type of flow channel is of interest to MAPLE-type nuclear research reactors. The flow regime maps are determined by visual observations and observation of waveforms shown by a capacitance-type void fraction meter. The experimental results show that the inclusion of the finned hexagonal bundle shifts the flow regime transition boundaries toward higher water flow rates. Existing flow regime maps based on pipe flow require slight modifications when applied to the hexagonal flow channel with and without a MAPLE-type finned hexagonal bundle. The proposed theoretical model agrees well with experimental results.

Science.gov (United States)

A comparison of benthic biodiversity in the North Sea, English Channel, and Celtic Seas. ICES J. Mar. Sci./J. Cons. int. Explor. Mer 56: 228-246. ...

Energy Technology Data Exchange (ETDEWEB)

A Bianchi type-IX cosmological model has been found as a solution of Einstien's vacuum field equations with a cosmological constant. The solution represents a rotating generalziation fo the de Sitter universe. This universe shows a transition to exponential expansion and the vorticity begins to decay exponentially at the grand-unified-theory time. The point of time for this transition is independent of the magnitude of the vorticity. During the Guth inflationary era the vorticity decays by a factor of the order 10 US.

International Nuclear Information System (INIS)

An investigation of the Ll x-#gamma# angular correlations following the decay of "2"0"7Bi is done by using a Si(Li) semiconductor counter as L x-ray detector. Coincidence measurements at five different angles were made between the 570-keV #gamma# ray (gated in the movable counter) and the Ll x spectrum (displayed in a multichannel analyzer).

CERN Document Server

Using data collected with the BESII detector at $e^{+}e^{-}$ storage ring Beijing Electron Positron Collider, the measurements of relative branching fractions for seven Cabibbo suppressed hadronic weak decays $D^0 \\to K^- K^+$, $\\pi^+ \\pi^-$, $K^- K^+ \\pi^+ \\pi^-$ and $\\pi^+ \\pi^+ \\pi^- \\pi^-$, $D^+ \\to \\bar{K^0} K^+$, $K^- K^+ \\pi^+$ and $\\pi^- \\pi^+ \\pi^+$ are presented.

Energy Technology Data Exchange (ETDEWEB)

It is shown that observations of the lithium isotope ratio in high surface temperature Population II stars may be critical to cosmological nucleosynthesis models. In particular, decaying particle scenarios as derived in some supersymmetric models may stand or fall with such observations. 18 references.

International Nuclear Information System (INIS)

The European Research and Development Program on decay heat removal by natural convection for the European Fast Reactor (EFR) covers the calculational methods and the model experiments performed for code validation. The studies concentrate on important physical effects of the cooling modes within the primary system and the direct reactor cooling circuits and include fundamental tests as well as reactor experiments. (author)

International Nuclear Information System (INIS)

The status of Monte Carlo system for the simulation of Bremsstrahlung in arbitrary decays and for the decay itself of #tau# -lepton is reviewed. During the last #tau# -lepton conference in 2010 several developments of the last two years have been presented: (i) For the TAUOLA Monte Carlo generator of #tau# -lepton decays, automated and simultaneous use of many versions of form-factors for the calculation of optional weights for fits was developed and checked to work in Belle and BaBar software environment. On-going work on alternative parameterizations of hadronic decays is presented too. (ii) The TAUOLA universal interface based on HepMC (the C++ event record) is now public. A similar interface for PHOTOS is now also public. (iii) Extension of PHOTOS Monte Carlo for QED Bremsstrahlung in decays featuring kernels based on complete first order matrix element are gradually becoming ...

UK PubMed Central (United Kingdom)

Using an anti-receptor mAb that blocks the attachment of echovirus 7 and related viruses (echoviruses 13, 21, 29 and 33), we have isolated a complementary DNA clone that encodes the human decay-accelerating...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The ..beta.. decay half-lives of neutron-rich isotopes with Z=24-28 are calculated in the QRPA with a Gamow-Teller residual interaction. For odd-mass and odd-odd systems QRPA phonon correlations are introduced to quasiparticle transitions in first-order perturbation. The calculated half-lives agree very well with the experimental values. For later application of this model to nuclei far from stability, we have examined the dependence of the calculated half-lives on the model parameters.

CERN Document Server

We consider the physics and collider phenomenology of quirks that transform nontrivially under QCD color, SU(2)_W as well as an SU(N)_{ic} infracolor group. Our main motivation is to show that the recent Wjj excess observed by CDF naturally arises in quirky models. The basic pattern is that several different quirky states can be produced, some of which beta-decay during or after spin-down, leaving the lightest electrically neutral quirks to hadronize into a meson that subsequently decays into gluon jets. We analyze LEP II, Tevatron, UA2, and electroweak precision constraints, identifying the simplest viable models: scalar quirks ("squirks") transforming as color triplets, SU(2)_W triplets and singlets, all with vanishing hypercharge. We calculate production cross sections, weak decay, spin-down, meson decay rates, and estimate efficiencies. The novel features of our quirky model includes: quirkonium ...

Energy Technology Data Exchange (ETDEWEB)

The authors measure the dipion mass spectrum in X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -} decays using 360 pb{sup -1} of {bar p}p collisions at {radical}s = 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ({sup 3}S{sub 1}, {sup 1}P{sub 1}, and {sup 3}D{sub J}) charmonia decaying to J/{psi}{pi}{sup +}{pi}{sup -}, as well as event C-parity states in which the pions are from {rho}{sup 0} decay. The latter case also encompasses exotic interpretations, such as a D{sup 0}{bar D}*{sup 0} molecule. Only the {sup 3}S{sub 1} and J/{psi} {rho} hypotheses are compatible with the data. Since {sup 3}S{sub 1} is untenable on other grounds, decay via J/{psi} {rho} is favored, which implies C = +1 for the X(3872). Models for different J/{psi}-{rho} angular momenta L are considered. Flexibility in the models, especially the introduction of {rho}-{omega} ...

UK PubMed Central (United Kingdom)

BackgroundWhen eukaryotic cells are deprived of amino acids, uncharged tRNAs accumulate and activate the conserved GCN2 protein kinase. Activated Gcn2p up-regulates the general amino...Full Text Available

Science.gov (United States)

A general palladium-catalyzed carbonylative Sonogashira coupling of benzyl chlorides with terminal acetylenes has been established. Depending on the alkyne 1,4-diaryl-3-butyn-2-ones or substituted furanones are obtained in moderate to good yields. Best catalytic performance is achieved applying a mixed Pd(PPh(3))Cl(2)/P(OPh)(3) catalyst system. PMID:21968528

UK PubMed Central (United Kingdom)

A multiple comparison approach using whole genome transcriptional arrays was used to identify genes and pathways involved in calorie restriction/dietary restriction (DR) life span extension in Drosophila....Full Text Available

International Nuclear Information System (INIS)

Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of ...

UK PubMed Central (United Kingdom)

Spider venoms provide a highly valuable source of peptide toxins that act on a wide diversity of membrane-bound receptors and ion channels. In this work, we report isolation, biochemical analysis, and...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow patterns and frictional pressure gradients in flow in small, rectangular channels are being studies as part of a larger research program addressing phase-change heat transfer of pure refrigerants and refrigerant mixtures in plate-fin heat exchangers. Small rectangular flow channels were selected as representative of plain fin geometries. The particular channel reported herein has dimensions of 19.05 {times} 3.18 mm. Adiabatic flows of air/water mixtures, with the flow channel horizontal and the channel exit at near-atmospheric conditions, were utilized in the experiments. Analysis and interpretation of the pressure data relative to observed flow pattern transitions led to an objective method for determining the plug/bubble-to-slug flow transition. This method, together with visual observations, supplemented with photographic data, was used to develop a flow pattern ...

British Library Electronic Table of Contents (United Kingdom)

The steady-state advective flow in a long horizontal rectangular channel with rigid adiabatic boundaries in the presence of a uniform longitudinal pressure gradient is investigated. The stability of this flow with respect to perturbations of various types is studied. The dependence of the critical Rayleigh number on the Prandtl number is found for various aspect ratios.

Science.gov (United States)

Channel plasmon polaritons (CPPs) propagating along the bottom of subwavelength grooves cut into a metal surface were recently shown to exhibit strong confinement combined with low propagation loss, a feature that makes this guiding configuration very promising for the realisation of ultra-compact photonic components. Here, the results of our investigations of CPP guiding by V-grooves cut into gold are presented, demonstrating efficient large-angle bending and splitting of radiation as well as waveguide-ring resonators and Bragg grating filters.

UK PubMed Central (United Kingdom)

We have shown previously that raising extracellular Ca²+ inhibited the apical 70-pS K channel in the thick ascending limb (TAL; Wang, W.H., M. Lu, and S.C. Hebert. 1996. Am....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

In scattering of channeled particles by point defects and in emission of gamma rays in the spontaneous-radiation spectral region conditions are attained where the momentum transferred to the defect is taken up by the crystal as a whole. This leads to coherent and interference effects in the radiation from the crystal defects. When the longitudinal momentum transferred is zero, an induced radiation effect appears in the transitions between the states of transverse motion.

British Library Electronic Table of Contents (United Kingdom)

The interaction between gravity convection and Marangoni convection in a horizontal rectangular channel filled with a liquid containing a surfactant and a drop of another liquid is numerically investigated. For large Schmidt numbers the occurring oscillatory regime of solutal convection is analyzed. In the model with a surface phase the effect of the adsorption and desorption processes on the convective flow structure is determined. The corresponding initial and boundary value problem is solved using a difference method.

Energy Technology Data Exchange (ETDEWEB)

An attempt was made to minimize the channeling tail by implantation along a random equivalent direction following a careful alignment of the target. In order to analytically determine the random equivalent directions, critical angles for channeling were mapped on a stereogram. Boron ions with energies of 17 and 45 keV are implanted along specified directions determined from the map. The depth distribution of the dopant is profiled by SIMS and the effects of water orientation upon the channeling tail are noted. Industrial common use of a 7/sup 0/ tilt is not optimum. However, implantation with the wafer tilted at 5.5 +/- 0.5/sup 0/ from the surface normal and rotated at 7.0 +/- 0.5/sup 0/ from a (100) plane shows the least channel-tail compared to implantation along other directions. Rapid thermal annealing (RTA) is a promising annealing method for shallow junction formation. Transient enhanced diffusion ...

International Nuclear Information System (INIS)

Obtained experimental data on integral cross sections (ICS) of inelastic scattering of 50.5 MeV #alpha# particles with the excitation of "6","7Li, "9Be, "1"2","1"3C, "1"4C, "1"4N, "2"0Ne, "2"4Mg, "2"8Si nucleus low-lying energy levels are discussed. Regularities, detected in the behaviour of ICS forward scattering for 20-90 deg angles and backscattering for 90-160 deg angles for the target-nucleus under investigation are considered. Effect of reaction open channel number on #alpha#-particle scattering ICS where n,p,d- and #alpha#-channels were considered as the main channels for all the target-nuclei, is discussed. Dependence of #alpha#-particle scattering ICS on the target-nucleus level excitation energy and dependences of reaction open channel number on the channel spin, calculated for 50.5 MeV #alpha# particles and different target nuclei are shown in the diagrams. It is noted ...

Energy Technology Data Exchange (ETDEWEB)

In CANDU reactors, the Regional Overpower Protection Trip (ROPT) system protects the reactor against overpowers in the reactor fuel, whether due to localized peaking within the core or a general increase in core power levels. Due to Primary Heat-Transport System (PHTS) aging the ROP trip setpoint is decreasing over time. Reductions in ROP trip setpoints are required to maintain the required trip-probability and ROP trip effectiveness, and results in a decrease of the ROP margin-to-trip during normal operation. In addition, full power operation can be threatened. In this point, to recover ROPT margin, channel power needs to be redistributed. ROPT setpoint is very conservative in normal operation because distortion of regional overpower is over 1.2 times as nominal power in slow loss of regulation (SLOR). Channel power ratio (CPR) is enough low except the limiting channel of which worst case of design basis flux shape. If the ...

Energy Technology Data Exchange (ETDEWEB)

A heat transfer (condenser) of a domestic freezer was tested in a vertical channel in order to study the influence of the chimney effect in the optimization of the heat transfer coefficient. The variation of the opening of the channel, position and the heating power of the heat exchanger in the heat transfer coefficient was considered. The influence of the surface emissivity on the heat transfer by thermal radiation was studied with the heat exchanger testes without paint and with black paint. The air velocity entering the channel was measured with a hot wire anemometer. In order to evaluate the chimney effect, the heat exchanger was testes in a open ambient. This situation simulates its operational conditions when installed on the freezer system. The variables collected in the experimental procedures was gathered in the form of dimensionless parameters as Nusselt, Rayleigh, Grashof and Prandtl numbers, and dimensional ...

Science.gov (United States)

Thesis. Five-particle shell-model calculations, using a spin-dependent potential, were performed for the nucleus /sup 101/Tc. The effects of varying the single-particle energy differences and the strengths of the spin-dependent and pairing terms are discussed. The isobars /sup 101/Mo and /sup 101/Tc were chemically separated to enable the detailed study of their decay schemes. As a result, 184 gamma rays were observed in the decay of /sup 101/Mo, and 169 of them were assigned to 45 levels in /sup 101/Tc. In the decay of /sup 101/Tc, 27 gamma rays were observed, and 26 of them were assigned to 11 levels in /sup 101/Ru. In a study of the decays of /sup 142/Xe and /sup 142/Cs the TRI STAN on-line isotope separator was used to separate the 142 mass chain produced in /sup 235/U fission with /sup 142/2Xe as the emanating and accelerated nuclide. Isobaric separation of /sup ...

Energy Technology Data Exchange (ETDEWEB)

An analysis is presented of the electron temperature in a linear device which includes the effect of thermal conduction, heat flux limit, radiation, and end plugs. It is found that the thermal conduction and the heat flux limit are dominant in the initial phase of cooling, while the later phase is almost completely controlled by radiation that spatially homogenizes the temperature distribution. In the case of bremsstrahlung, within the frame of the present model, the temperature decays to zero in a finite time. This process takes the form of a cooling wave that moves from the ends of the column to the center. Impurities cause a milder, exponential decay, which is still much faster than the algebraic conduction decay. The thermal effectiveness of the end plugs is described by a convective transfer coefficient h/sub p/. Its scaling law (in terms of the coupled plamsa-plug system) reveals that a very high plug-plasma density ...

CERN Document Server

We propose an X-ray mission called Xenia to search for decaying superweakly interacting Dark Matter particles (super-WIMP) with a mass in the keV range. The mission and its observation plan are capable of providing a major break through in our understanding of the nature of Dark Matter (DM). It will confirm, or reject, predictions of a number of particle physics models by increasing the sensitivity of the search for decaying DM by about two orders of magnitude through a wide-field imaging X-ray spectrometer in combination with a dedicated observation program. The proposed mission will provide unique limits on the mixing angle and mass of neutral leptons, right handed partners of neutrinos, which are important Dark Matter candidates. The existence of these particles is strongly motivated by observed neutrino flavor oscillations and the problem of baryon asymmetry of the Universe. In super-WIMP models, the details of the formation of the cosmic ...

CERN Document Server

We study the rates allowed for the Higgs-mediated decays $B_{s,d}^0\\to\\mu\\tau, e\\tau$ and $\\tau\\to \\mu\\mu\\mu, e\\mu\\mu$ in supersymmetric seesaw models, assuming that the only source of lepton flavour violation (LFV) is the renormalization of soft supersymmetry-breaking terms due to off-diagonal singlet-neutrino Yukawa interactions. These decays are strongly correlated with, and constrained by, the branching ratios for $B_{s,d}^0\\to\\mu\\mu$ and $\\tau\\to \\mu(e)\\gamma.$ Parametrizing the singlet-neutrino Yukawa couplings $Y_\