WorldWideScience

Sample records for frozen rydberg gas

  1. One-Dimensional Rydberg Gas in a Magnetoelectric Trap

    International Nuclear Information System (INIS)

    Mayle, Michael; Hezel, Bernd; Lesanovsky, Igor; Schmelcher, Peter

    2007-01-01

    We study the quantum properties of Rydberg atoms in a magnetic Ioffe-Pritchard trap which is superimposed by a homogeneous electric field. Trapped Rydberg atoms can be created in long-lived electronic states exhibiting a permanent electric dipole moment of several hundred Debye. The resulting dipole-dipole interaction in conjunction with the radial confinement is demonstrated to give rise to an effectively one-dimensional ultracold Rydberg gas with a macroscopic interparticle distance. We derive analytical expressions for the electric dipole moment and the required linear density of Rydberg atoms

  2. Evidence of Antiblockade in an Ultracold Rydberg Gas

    Science.gov (United States)

    Amthor, Thomas; Giese, Christian; Hofmann, Christoph S.; Weidemüller, Matthias

    2010-01-01

    We present the experimental observation of the antiblockade in an ultracold Rydberg gas recently proposed by Ates et al. [Phys. Rev. Lett. 98, 023002 (2007)PRLTAO0031-900710.1103/PhysRevLett.98.023002]. Our approach allows the control of the pair distribution in the gas and is based on a strong coupling of one transition in an atomic three-level system, while introducing specific detunings of the other transition. When the coupling energy matches the interaction energy of the Rydberg long-range interactions, the otherwise blocked excitation of close pairs becomes possible. A time-resolved spectroscopic measurement of the Penning ionization signal is used to identify slight variations in the Rydberg pair distribution of a random arrangement of atoms. A model based on a pair interaction Hamiltonian is presented which well reproduces our experimental observations and allows one to deduce the distribution of nearest-neighbor distances.

  3. Evolution from Rydberg gas to ultracold plasma in a supersonic atomic beam of Xe

    International Nuclear Information System (INIS)

    Hung, J; Sadeghi, H; Schulz-Weiling, M; Grant, E R

    2014-01-01

    A Rydberg gas of xenon, entrained in a supersonic atomic beam, evolves slowly to form an ultracold plasma. In the early stages of this evolution, when the free-electron density is low, Rydberg atoms undergo long-range ℓ-mixing collisions, yielding states of high orbital angular momentum. The development of high-ℓ states promotes dipole–dipole interactions that help to drive Penning ionization. The electron density increases until it reaches the threshold for avalanche. Ninety μs after the production of a Rydberg gas with the initial state, n 0 ℓ 0 =42d, a 432 V cm −1 electrostatic pulse fails to separate charge in the excited volume, an effect which is ascribed to screening by free electrons. Photoexcitation cross sections, observed rates of ℓ-mixing, and a coupled-rate-equation model simulating the onset of the electron-impact avalanche point consistently to an initial Rydberg gas density of 5×10 8 cm −3 . (paper)

  4. Evolution from Rydberg gas to ultracold plasma in a supersonic atomic beam of Xe

    Science.gov (United States)

    Hung, J.; Sadeghi, H.; Schulz-Weiling, M.; Grant, E. R.

    2014-08-01

    A Rydberg gas of xenon, entrained in a supersonic atomic beam, evolves slowly to form an ultracold plasma. In the early stages of this evolution, when the free-electron density is low, Rydberg atoms undergo long-range \\ell -mixing collisions, yielding states of high orbital angular momentum. The development of high-\\ell states promotes dipole-dipole interactions that help to drive Penning ionization. The electron density increases until it reaches the threshold for avalanche. Ninety μs after the production of a Rydberg gas with the initial state, {{n}_{0}}{{\\ell }_{0}}=42d, a 432 V cm-1 electrostatic pulse fails to separate charge in the excited volume, an effect which is ascribed to screening by free electrons. Photoexcitation cross sections, observed rates of \\ell -mixing, and a coupled-rate-equation model simulating the onset of the electron-impact avalanche point consistently to an initial Rydberg gas density of 5\\times {{10}^{8}}\\;c{{m}^{-3}}.

  5. Rydberg aggregates

    Science.gov (United States)

    Wüster, S.; Rost, J.-M.

    2018-02-01

    We review Rydberg aggregates, assemblies of a few Rydberg atoms exhibiting energy transport through collective eigenstates, considering isolated atoms or assemblies embedded within clouds of cold ground-state atoms. We classify Rydberg aggregates, and provide an overview of their possible applications as quantum simulators for phenomena from chemical or biological physics. Our main focus is on flexible Rydberg aggregates, in which atomic motion is an essential feature. In these, simultaneous control over Rydberg-Rydberg interactions, external trapping and electronic energies, allows Born-Oppenheimer surfaces for the motion of the entire aggregate to be tailored as desired. This is illustrated with theory proposals towards the demonstration of joint motion and excitation transport, conical intersections and non-adiabatic effects. Additional flexibility for quantum simulations is enabled by the use of dressed dipole-dipole interactions or the embedding of the aggregate in a cold gas or Bose-Einstein condensate environment. Finally we provide some guidance regarding the parameter regimes that are most suitable for the realization of either static or flexible Rydberg aggregates based on Li or Rb atoms. The current status of experimental progress towards enabling Rydberg aggregates is also reviewed.

  6. Orbital alignment effects in near-resonant Rydberg atoms-rare gas collisions

    International Nuclear Information System (INIS)

    Isaacs, W.A.; Morrison, M.A.

    1993-01-01

    Recent experimental and theoretical studies of near-resonant energy transfer collisions involving rare-gas atoms and alkali or alkaline earth atoms which have been initially excited to an aligned state via one or more linearly polarized rasters have yielded a wealth of insight into orbital alignment and related effects. We have extended this inquiry to initially aligned Rydberg states, examining state-to-state and alignment-selected cross sections using quantum collision theory augmented by approximations appropriate to the special characteristics of the Rydberg state (e.g., the quasi-free-electron model and the impulse approximation)

  7. Fermionic Collective Excitations in a Lattice Gas of Rydberg Atoms

    International Nuclear Information System (INIS)

    Olmos, B.; Gonzalez-Ferez, R.; Lesanovsky, I.

    2009-01-01

    We investigate the many-body quantum states of a laser-driven gas of Rydberg atoms confined to a large spacing ring lattice. If the laser driving is much stronger than the van der Waals interaction among the Rydberg atoms, these many-body states are collective fermionic excitations. The first excited state is a spin wave that extends over the entire lattice. We demonstrate that our system permits us to study fermions in the presence of disorder although no external atomic motion takes place. We analyze how this disorder influences the excitation properties of the fermionic states. Our work shows a route towards the creation of complex many-particle states with atoms in lattices.

  8. Positive-column plasma studied by fast-flow glow discharge mass spectrometry: Could it be a 'Rydberg gas?'

    International Nuclear Information System (INIS)

    Mason, Rod S.; Miller, Pat D.; Mortimer, Ifor; Mitchell, David J.; Dash, Neil A.

    2003-01-01

    Ions created from the fast-flowing positive column plasma of a glow discharge were monitored using a high voltage magnetic sector mass spectrometer. Since the field gradient and sheath potentials created by the plasma inside the source opposed cation transfer, it is inferred that the ions detected were the field-ionized Rydberg species. This is supported by the mass spectral changes which occurred when a negative bias was applied to the sampling aperture and by the contrasting behavior when attached to a quadrupole analyzer. Reaction with H 2 (titrated into the flowing plasma) quenched not only the ionization of discharge gas Rydberg atoms but also the passage of electric current through the plasma, without significant changes to the field and sheath potentials. Few 'free' ions were present and the lifetimes of the Rydberg atoms detected were much longer than seen in lower pressure experiments, indicating additional stabilization in the plasma environment. The observations support the model of the flowing plasma, given previously [R. S. Mason, P. D. Miller, and I. P. Mortimer, Phys. Rev. E 55, 7462 (1997)] as mainly a neutral Rydberg atom gas, rather than a conventional ion-electron plasma

  9. Polyatomic Trilobite Rydberg Molecules in a Dense Random Gas.

    Science.gov (United States)

    Luukko, Perttu J J; Rost, Jan-Michael

    2017-11-17

    Trilobites are exotic giant dimers with enormous dipole moments. They consist of a Rydberg atom and a distant ground-state atom bound together by short-range electron-neutral attraction. We show that highly polar, polyatomic trilobite states unexpectedly persist and thrive in a dense ultracold gas of randomly positioned atoms. This is caused by perturbation-induced quantum scarring and the localization of electron density on randomly occurring atom clusters. At certain densities these states also mix with an s state, overcoming selection rules that hinder the photoassociation of ordinary trilobites.

  10. Collisional destruction of fast hydrogen Rydberg atoms

    International Nuclear Information System (INIS)

    King, M.R.

    1984-01-01

    A new modulated electric field technique was developed to study Rydberg atom destruction processes in a fast beam. The process of destruction of a band of Rydberg atom destruction of a band of Rydberg atoms through the combined processes of ionization, excitation, and deexcitation was studied for collisions with gas targets. Rydberg atoms of hydrogen were formed by electron capture, and detected by field ionization. The modulated field technique described proved to be an effective technique for producing a large signal for accurate cross section measurements. The independent particle model for Rydberg atom destruction processes was found to hold well for collisions with molecular nitrogen, argon, and carbon dioxide. The resonances in the cross sections for the free electron scattering with these targets were found to also occur in Rydberg destruction. Suggestions for future investigations of Rydberg atom collision processes in the fast beam regime are given

  11. Fast-responding property of electromagnetically induced transparency in Rydberg atoms

    Science.gov (United States)

    Zhang, Qi; Bai, Zhengyang; Huang, Guoxiang

    2018-04-01

    We investigate the transient optical response property of an electromagnetically induced transparency (EIT) in a cold Rydberg atomic gas. We show that both the transient behavior and the steady-state EIT spectrum of the system depend strongly on Rydberg interaction. Especially, the response speed of the Rydberg-EIT can be five times faster (and even higher) than the conventional EIT without the Rydberg interaction. For comparison, two different theoretical approaches (i.e., two-atom model and many-atom model) are considered, revealing that Rydberg blockade effect plays a significant role for increasing the response speed of the Rydberg-EIT. The fast-responding Rydberg-EIT by using the strong, tunable Rydberg interaction uncovered here is not only helpful for enhancing the understanding of the many-body dynamics of Rydberg atoms but also useful for practical applications in quantum information processing by using Rydberg atoms.

  12. Dipole-dipole interactions in a hot atomic vapor and in an ultracold gas of Rydberg atoms

    Science.gov (United States)

    Sautenkov, V. A.; Saakyan, S. A.; Bronin, S. Ya; Klyarfeld, A. B.; Zelener, B. B.; Zelener, B. V.

    2018-01-01

    In our paper ideal and non-ideal gas media of neutral atoms are analyzed. The first we discuss a dipole broadening of atomic transitions in excited dilute and dense metal vapors. Then the theoretical studies of the dipole-dipole interactions in dense ultracold gas of Rydberg atoms are considered. Possible future experiments on a base of our experimental arrangement are suggested.

  13. Rydberg states

    International Nuclear Information System (INIS)

    Brouillard, F.

    1983-01-01

    This chapter considers the formation of Rydberg atoms; their radiative decay; their behavior in electric and electromagnetic fields; and their collisions with atoms and ions. Discusses electron capture into high excited states; laser excitation of Rydberg states; Stark shift and Stark mixing; field ionization; ionization in oscillating fields; thermal collisions of Rydberg atoms; fast collisions of Rydberg atoms; n-changing collisions; and charge exchange. Points out that a large amount of experimental work has been done on collisions of Rydberg atoms with neutral perturbers at thermal energies, and most of it concerns the destruction of Rydberg alkali atoms in collisions with rare gases

  14. Cooperative Excitation and Many-Body Interactions in a Cold Rydberg Gas

    DEFF Research Database (Denmark)

    Viteau, Matthieu; Huillery, Paul; Bason, Mark George

    2012-01-01

    of the dipole blockade is the suppression of fluctuations in the counting statistics of Rydberg excitations, of which some evidence has been found in previous experiments. Here we present experimental results on the dynamics and the counting statistics of Rydberg excitations of ultracold rubidium atoms both...... on and off resonance, which exhibit sub- and super-Poissonian counting statistics, respectively. We compare our results with numerical simulations using a novel theoretical model based on Dicke states of Rydberg atoms including dipole-dipole interactions, finding good agreement between experiment and theory.......The dipole blockade of Rydberg excitations is a hallmark of the strong interactions between atoms in these high-lying quantum states [ M. Saffman, T. G. Walker and K. Mølmer Rev. Mod. Phys. 82 2313 (2010); D. Comparat and P. Pillet J. Opt. Soc. Am. B 27 A208 (2010)]. One of the consequences...

  15. Cold Rydberg molecules

    Science.gov (United States)

    Raithel, Georg; Zhao, Jianming

    2017-04-01

    Cold atomic systems have opened new frontiers at the interface of atomic and molecular physics. These include research on novel types of Rydberg molecules. Three types of molecules will be reviewed. Long-range, homonuclear Rydberg molecules, first predicted in [1] and observed in [2], are formed via low-energy electron scattering of the Rydberg electron from a ground-state atom within the Rydberg atom's volume. The binding mostly arises from S- and P-wave triplet scattering. We use a Fermi model that includes S-wave and P-wave singlet and triplet scattering, the fine structure coupling of the Rydberg atom and the hyperfine structure coupling of the 5S1/2 atom (in rubidium [3]). The hyperfine structure gives rise to mixed singlet-triplet potentials for both low-L and high-L Rydberg molecules [3]. A classification into Hund's cases [3, 4, 5] will be discussed. The talk further includes results on adiabatic potentials and adiabatic states of Rydberg-Rydberg molecules in Rb and Cs. These molecules, which have even larger bonding length than Rydberg-ground molecules, are formed via electrostatic multipole interactions. The leading interaction term of neutral Rydberg-Rydberg molecules is between two dipoles, while for ionic Rydberg molecules it is between a dipole and a monopole. NSF (PHY-1506093), NNSF of China (61475123).

  16. Simulation of coherent interactions between Rydberg atoms

    International Nuclear Information System (INIS)

    Robicheaux, F.; Hernandez, J.V.; Topcu, T.; Noordam, L.D.

    2004-01-01

    The results of a theoretical investigation of the coherent interaction between many Rydberg atoms are reported. The atoms are assumed to move very little during the time range we investigate. We describe the basic interaction between atoms and show that (contrary to previous theoretical studies) the interaction between the atoms can be coherent. The band structure for a perfect lattice of atoms and the density of states for an amorphous distribution of atoms are presented. We also give results for when the atoms are roughly positioned in a lattice. Finally, we performed detailed calculations to understand when the Rydberg interactions are too strong for an essential states type of approximation. The relevance of our results to previous measurements in a Rydberg gas and to possible future experiments is discussed

  17. Correlations between interacting Rydberg atoms

    DEFF Research Database (Denmark)

    Paris-Mandoki, Asaf; Braun, Christoph; Hofferberth, Sebastian

    2018-01-01

    This paper is a short introduction to Rydberg physics and quantum nonlinear optics using Rydberg atoms. It has been prepared as a compliment to a series of lectures delivered during the Latin American School of Physics "Marcos Moshinsky" 2017. We provide a short introduction to the properties...... of individual Rydberg atoms and discuss in detail how the interaction potential between Rydberg atom pairs is calculated. We then discuss how this interaction gives rise to the Rydberg blockade mechanism. With the aid of hallmark experiments in the field applications of the blockade for creating correlated...

  18. Periodically Driven Array of Single Rydberg Atoms

    Science.gov (United States)

    Basak, Sagarika; Chougale, Yashwant; Nath, Rejish

    2018-03-01

    An array of single Rydberg atoms driven by a temporally modulated atom-field detuning is studied. The periodic modulation effectively modifies the Rabi coupling, leading to unprecedented dynamics in the presence of Rydberg-Rydberg interactions, in particular, blockade enhancement, antiblockades, and state-dependent population trapping. Interestingly, the Schrieffer-Wolf transformation reveals a fundamental process in Rydberg gases, correlated Rabi coupling, which stems from the extended nature of the Rydberg-Rydberg interactions. Also, the correlated coupling provides an alternative depiction for the Rydberg blockade, exhibiting a nontrivial behavior in the presence of periodic modulation. The dynamical localization of a many-body configuration in a driven Rydberg lattice is discussed.

  19. Carbon dioxide gas hydrates accumulation in freezing and frozen sediments

    Energy Technology Data Exchange (ETDEWEB)

    Chuvilin, E.; Guryeva, O. [Moscow State Univ., Moscow (Russian Federation). Dept. of Geology

    2008-07-01

    Carbon dioxide (CO{sub 2}) hydrates and methane hydrates can be formed, and exist under natural conditions. The permafrost area has been considered as an environment for the potential disposal of CO{sub 2}. The favorable factors for preserving CO{sub 2} in liquid and gas hydrate states in frozen sediments and under permafrost horizons are great thickness of frozen sediments; low permeability in comparison with thawed sediments; and favourable conditions for hydrates formation. Therefore, research on the formation and existence conditions of CO{sub 2} gas hydrates in permafrost and under permafrost sediments are of great importance for estimation of CO{sub 2} disposal conditions in permafrost, and for working out specific sequestration schemes. This paper presented the results of an experimental study on the process of carbon dioxide (CO{sub 2}) gas hydrates formation in the porous media of sediments under positive and negative temperatures. Sediment samples of various compositions including those selected in the permafrost area were used. The research was conducted in a special pressure chamber, which allowed to monitor pressure and temperature. The study used the monitoring results in order to make quantitative estimation of the kinetics of CO{sub 2} hydrates accumulation in the model sediments. Results were presented in terms of kinetics of CO{sub 2} hydrates accumulation in the porous media at positive and negative temperatures; kinetics of CO{sub 2} hydrates accumulation in various porous media; gas hydrate-former influence on kinetics of hydrates accumulation in frozen sediments; and influence of freezing on CO{sub 2} hydrates accumulation in porous media. It was concluded that hydrate accumulation took an active place in porous media not only under positive, but also under high negative temperatures, when the water was mainly in the form of ice in porous media. 27 refs., 3 tabs., 5 figs.

  20. Janne Rydberg - his life and work

    International Nuclear Information System (INIS)

    Martinson, I.; Curtis, L.J.

    2005-01-01

    The Rydberg formula is emblematic of atomic spectroscopy. We review here the personal background, research accomplishments, and academic career of its discoverer, Janne Rydberg. Although his formula is often introduced as a generalization of the hydrogenic Balmer formula, Rydberg's work was independent of Balmer's, and displayed great ingenuity and a rare ability to recognize hidden patterns in complex numerical data. Although his discoveries attracted wide attention, experimental physics was then considered inseparable from measurement, and the fact that Rydberg's insightful formulations used the data of others impeded his academic career. Although Rydberg did not live to see the full theoretical implications of his discoveries, the vigorous study of Rydberg atoms continues today

  1. Accurate values of polarizabilities from Rydberg states

    International Nuclear Information System (INIS)

    Patil, S.H.

    1997-01-01

    From the theoretical point of view, there are several properties of Rydberg states which are of interest, interaction of Rydberg atoms with each other, scattering of electrons from Rydberg atoms, interaction of Rydberg atoms with external electromagnetic fields, etc. In this paper the discussion is confined to the particular aspect: the deviations of the energies of Rydberg states from hydrogenic energies, their calculations and their implications from the properties of the core, i.e. the system that remains after Rydberg electron is removed

  2. Correlations between interacting Rydberg atoms

    Science.gov (United States)

    Paris-Mandoki, Asaf; Braun, Christoph; Hofferberth, Sebastian

    2018-04-01

    This paper is a short introduction to Rydberg physics and quantum nonlinear optics using Rydberg atoms. It has been prepared as a compliment to a series of lectures delivered during the Latin American School of Physics "Marcos Moshinsky" 2017. We provide a short introduction to the properties of individual Rydberg atoms and discuss in detail how the interaction potential between Rydberg atom pairs is calculated. We then discuss how this interaction gives rise to the Rydberg blockade mechanism. With the aid of hallmark experiments in the field applications of the blockade for creating correlated quantum systems are discussed. Our aim is to give an overview of this exciting and rapidly evolving field. The interested reader is referred to original work and more comprehensive reviews and tutorials for further details on these subjects.

  3. The l-mixing cross section of Rydberg states of atomic Rb and the scaling LAW

    International Nuclear Information System (INIS)

    Liu Hong; Chen Aiqiu; Li Baiwen

    1991-01-01

    On the basis of impulse approximate method, a kind of analytical wavefunctions based on a potential model was used to calculate the l mixing cross section of thermal collision of Rydberg states of atomic Rb with rare gas (He, Ne). The results were compared with the experimental results and other theoretical values. These results show that there exists a kind of scaling law for the l mixing cross section of Rydberg alkali atoms

  4. Auto transfer to Rydberg states and indirect stabilization following double capture

    Energy Technology Data Exchange (ETDEWEB)

    Roncin, P.; Gaboriaud, M.N.; Barat, M. (Paris-11 Univ., 91 - Orsay (France)); Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Benhenni, M. (Toulouse-3 Univ., 31 (France)); Bachau, H.; Harel, C. (Bordeaux-1 Univ., 33 (France))

    1993-11-28

    Two-electron capture by slow multiply charged ions colliding on rare-gas target at keV energies is known to populate doubly excited states of the projectile with large cross sections. Though these states are dominantly autoionizing, important radiative decay following double capture have been reported, among which the direct observation of the fluorescence from Rydberg states. A mechanism based on post-collisional effects was proposed, in which Rydberg states are fed from the quasi-symmetrical doubly excited states initially populated. In this paper, a quantitative analysis of this effect is developed leading to a simple model which is applied to N[sup 7+] on He and Ar collisions. (author).

  5. Auto transfer to Rydberg states and indirect stabilization following double capture

    International Nuclear Information System (INIS)

    Roncin, P.; Gaboriaud, M.N.; Barat, M.; Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Benhenni, M.; Bachau, H.; Harel, C.

    1993-01-01

    Two-electron capture by slow multiply charged ions colliding on rare-gas target at keV energies is known to populate doubly excited states of the projectile with large cross sections. Though these states are dominantly autoionizing, important radiative decay following double capture have been reported, among which the direct observation of the fluorescence from Rydberg states. A mechanism based on post-collisional effects was proposed, in which Rydberg states are fed from the quasi-symmetrical doubly excited states initially populated. In this paper, a quantitative analysis of this effect is developed leading to a simple model which is applied to N 7+ on He and Ar collisions. (author)

  6. High Angular Momentum Rydberg Wave Packets

    Science.gov (United States)

    Wyker, Brendan

    2011-12-01

    High angular momentum Rydberg wave packets are studied. Application of carefully tailored electric fields to low angular momentum, high- n (n ˜ 300) Rydberg atoms creates coherent superpositions of Stark states with near extreme values of angular momentum, ℓ. Wave packet components orbit the parent nucleus at rates that depend on their energy, leading to periods of localization and delocalization as the components come into and go out of phase with each other. Monitoring survival probability signals in the presence of position dependent probing leads to observation of characteristic oscillations based on the composition of the wave packet. The discrete nature of electron energy levels is observed through the measurement of quantum revivals in the wave packet localization signal. Time-domain spectroscopy of these signals allows determination of both the population and phase of individual superposition components. Precise manipulation of wave packets is achieved through further application of pulsed electric fields. Decoherence effects due to background gas collisions and electrical noise are also detailed. Quantized classical trajectory Monte-Carlo simulations are introduced and agree remarkably well with experimental results.

  7. Bohmian picture of Rydberg atoms

    Indian Academy of Sciences (India)

    Abstract. Unlike the previous theoretical results based on standard quantum mechanics that established the nearly elliptical shapes for the centre-of-mass motion in Rydberg atoms using numerical simulations, we show analytically that the Bohmian trajectories in Rydberg atoms are nearly elliptical.

  8. Electromagnetically Induced Transparency In Rydberg Atomic Medium

    Science.gov (United States)

    Deng, Li; Cong, Lu; Chen, Ai-Xi

    2018-03-01

    Due to possessing big principal quantum number, Rydberg atom has some unique properties, for example: its radiative lifetime is long, dipole moment is large, and interaction between atoms is strong and so on. These properties make one pay attention to Rydberg atoms. In this paper we investigate the effects of Rydberg dipole-dipole interactions on electromagnetically induced transparency (EIT) schemes and group velocity in three-level systems of ladder type, which provides theoretical foundation for exploring the linear and nonlinear characteristics of light in a Rydberg electromagnetically-induced-transparency medium.

  9. Expansion of an ultracold Rydberg plasma

    Science.gov (United States)

    Forest, Gabriel T.; Li, Yin; Ward, Edwin D.; Goodsell, Anne L.; Tate, Duncan A.

    2018-04-01

    We report a systematic experimental and numerical study of the expansion of ultracold Rydberg plasmas. Specifically, we have measured the asymptotic expansion velocities, v0, of ultracold neutral plasmas (UNPs) which evolve from cold, dense samples of Rydberg rubidium atoms using ion time-of-flight spectroscopy. From this, we have obtained values for the effective initial plasma electron temperature, Te ,0=mionv02/kB (where mion is the Rb+ ion mass), as a function of the original Rydberg atom density and binding energy, Eb ,i. We have also simulated numerically the interaction of UNPs with a large reservoir of Rydberg atoms to obtain data to compare with our experimental results. We find that for Rydberg atom densities in the range 107-109 cm-3, for states with principal quantum number n >40 , Te ,0 is insensitive to the initial ionization mechanism which seeds the plasma. In addition, the quantity kBTe ,0 is strongly correlated with the fraction of atoms which ionize, and is in the range 0.6 ×| Eb ,i|≲ kBTe ,0≲2.5 ×|Eb ,i| . On the other hand, plasmas from Rydberg samples with n ≲40 evolve with no significant additional ionization of the remaining atoms once a threshold number of ions has been established. The dominant interaction between the plasma electrons and the Rydberg atoms is one in which the atoms are deexcited, a heating process for electrons that competes with adiabatic cooling to establish an equilibrium where Te ,0 is determined by their Coulomb coupling parameter, Γe˜0.01 .

  10. Calculation of Rydberg interaction potentials

    International Nuclear Information System (INIS)

    Weber, Sebastian; Büchler, Hans Peter; Tresp, Christoph; Urvoy, Alban; Hofferberth, Sebastian; Menke, Henri; Firstenberg, Ofer

    2017-01-01

    The strong interaction between individual Rydberg atoms provides a powerful tool exploited in an ever-growing range of applications in quantum information science, quantum simulation and ultracold chemistry. One hallmark of the Rydberg interaction is that both its strength and angular dependence can be fine-tuned with great flexibility by choosing appropriate Rydberg states and applying external electric and magnetic fields. More and more experiments are probing this interaction at short atomic distances or with such high precision that perturbative calculations as well as restrictions to the leading dipole–dipole interaction term are no longer sufficient. In this tutorial, we review all relevant aspects of the full calculation of Rydberg interaction potentials. We discuss the derivation of the interaction Hamiltonian from the electrostatic multipole expansion, numerical and analytical methods for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source. (tutorial)

  11. Magnetic trapping of Rydberg atoms

    NARCIS (Netherlands)

    Niestadt, D.; Naber, J.; Kokkelmans, S.J.J.M.F.; Spreeuw, R.J.C.

    2016-01-01

    Magnetic trapping is a well-established technique for ground state atoms. We seek to extend this concept to Rydberg atoms. Rydberg atoms are important for current visions of quantum simulators that will be used in the near future to simulate and analyse quantum problems. Current efforts in Amsterdam

  12. Trapping of Rydberg atoms in tight magnetic microtraps

    NARCIS (Netherlands)

    Boetes, A.Q.G.; Skannrup, R.V.; Naber, J.; Kokkelmans, S.J.J.M.F.; Spreeuw, R.J.C.

    2018-01-01

    We explore the possibility to trap Rydberg atoms in tightly confining magnetic microtraps. The trapping frequencies for Rydberg atoms are expected to be influenced strongly by magnetic-field gradients. We show that there are regimes where Rydberg atoms can be trapped. Moreover, we show that

  13. Efficient Multiparticle Entanglement via Asymmetric Rydberg Blockade

    DEFF Research Database (Denmark)

    Saffman, Mark; Mølmer, Klaus

    2009-01-01

    We present an efficient method for producing N particle entangled states using Rydberg blockade interactions. Optical excitation of Rydberg states that interact weakly, yet have a strong coupling to a second control state is used to achieve state dependent qubit rotations in small ensembles. On t....... On the basis of quantitative calculations, we predict that an entangled quantum superposition state of eight atoms can be produced with a fidelity of 84% in cold Rb atoms.......We present an efficient method for producing N particle entangled states using Rydberg blockade interactions. Optical excitation of Rydberg states that interact weakly, yet have a strong coupling to a second control state is used to achieve state dependent qubit rotations in small ensembles...

  14. Correlated Photon Dynamics in Dissipative Rydberg Media

    Science.gov (United States)

    Zeuthen, Emil; Gullans, Michael J.; Maghrebi, Mohammad F.; Gorshkov, Alexey V.

    2017-07-01

    Rydberg blockade physics in optically dense atomic media under the conditions of electromagnetically induced transparency (EIT) leads to strong dissipative interactions between single photons. We introduce a new approach to analyzing this challenging many-body problem in the limit of a large optical depth per blockade radius. In our approach, we separate the single-polariton EIT physics from Rydberg-Rydberg interactions in a serialized manner while using a hard-sphere model for the latter, thus capturing the dualistic particle-wave nature of light as it manifests itself in dissipative Rydberg-EIT media. Using this approach, we analyze the saturation behavior of the transmission through one-dimensional Rydberg-EIT media in the regime of nonperturbative dissipative interactions relevant to current experiments. Our model is able to capture the many-body dynamics of bright, coherent pulses through these strongly interacting media. We compare our model with available experimental data in this regime and find good agreement. We also analyze a scheme for generating regular trains of single photons from continuous-wave input and derive its scaling behavior in the presence of imperfect single-photon EIT.

  15. Two electron Rydberg states

    International Nuclear Information System (INIS)

    Cooke, W.E.

    1981-01-01

    This paper addresses the study of two-electron Rydberg atoms. With Multichannel Quantum Defect Theory (MQDT), there is a technique for characterizing a spectra in terms of a small number of parameters. A survey of some important effects specific to two-electon Rydberg states, using primarily the alkaline earth atoms for examples, is made. The remainder of the paper deals with a discussion of the electron-electron interaction, including some of the basic points of MQDT. Energy exchange between two electrons is also addressed

  16. Electromagnetically induced transparency of ultra-long-range Rydberg molecules

    DEFF Research Database (Denmark)

    Mirgorodskiy, Ivan; Christaller, Florian; Braun, Christoph

    2017-01-01

    We study the impact of Rydberg molecule formation on the storage and retrieval of Rydberg polaritons in an ultracold atomic medium. We observe coherent revivals appearing in the storage and retrieval efficiency of stored photons that originate from simultaneous excitation of Rydberg atoms and Ryd...

  17. Auto transfer to Rydberg states during ion-atom collisions

    International Nuclear Information System (INIS)

    Bachau, H.; Harel, C.; Barat, M.; Roncin, P.; Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Benoit-Cattin, P.; Gleizes, A.; Benhenni, M.

    1993-01-01

    Electron capture by slow multiply charged ions colliding on rare-gas targets is known to populate highly excited states of the projectile. On the basis of experimental measurement of energy and angle differential cross-sections we have shown that capture to a resonant doubly excited state may lead to Autoionizing Double Capture (ADC) as well as to True Double Capture (TDC). In this model TDC appears as a two step post-collisional process, the state populated by the collision decays to (or delutes into) a dense adjacent Rydberg series, followed by radiative deexcitation of the inner electron of the (3,n) Rydberg states. We report here new experimental observations in electron spectra measured in N 7+ +He. Auto transfer to Rydber states has also important consequences on the determination of the lifetime of the autoionizing states, some discrepancies between theoretical width values for low N 5+ (4,4) resonant states will be discussed and partially resolved

  18. Auto transfer to Rydberg states during ion-atom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Bachau, H.; Harel, C. (Laboratoire des Collisions Atomiques, Unite Propre de Recherche 260 du CNRS, Universite Bordeaux I, 351 Cours de la Liberation, 33405 Talence (France)); Barat, M.; Roncin, P. (Laboratoire des Collisions Atomiques et Moleculaires, Unite associee 281 du CNRS, Universite de Paris Sud, Batiment 351, 91405 Orsay (France)); Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Benoit-Cattin, P.; Gleizes, A.; Benhenni, M. (IRSAMC, Unite associee 770 du CNRS, Universite Paul Sabatier, 118 route de Narbonne, 31062 Toulouse (France))

    1993-06-05

    Electron capture by slow multiply charged ions colliding on rare-gas targets is known to populate highly excited states of the projectile. On the basis of experimental measurement of energy and angle differential cross-sections we have shown that capture to a resonant doubly excited state may lead to Autoionizing Double Capture (ADC) as well as to True Double Capture (TDC). In this model TDC appears as a two step post-collisional process, the state populated by the collision decays to (or delutes into) a dense adjacent Rydberg series, followed by radiative deexcitation of the inner electron of the (3,n) Rydberg states. We report here new experimental observations in electron spectra measured in [ital N][sup 7+]+[ital He]. Auto transfer to Rydber states has also important consequences on the determination of the lifetime of the autoionizing states, some discrepancies between theoretical width values for low [ital N][sup 5+](4,4) resonant states will be discussed and partially resolved.

  19. revivals of Rydberg wave packets

    International Nuclear Information System (INIS)

    Bluhm, R.; Kostelecky, V.A.; Tudose, B.

    1998-01-01

    We examine the revival structure of Rydberg wave packets. The effects of quantum defects on wave packets in alkali-metal atoms and a squeezed-state description of the initial wave packets are also described. We then examine the revival structure of Rydberg wave packets in the presence of an external electric field, i.e., the revival structure of Stark wave packets. These wave packets have energies that depend on two quantum numbers and exhibit new types of interference behaviour

  20. D-state Rydberg electrons interacting with ultracold atoms

    Energy Technology Data Exchange (ETDEWEB)

    Krupp, Alexander Thorsten

    2014-10-02

    This thesis was established in the field of ultracold atoms where the interaction of highly excited D-state electrons with rubidium atoms was examined. This work is divided into two main parts: In the first part we study D-state Rydberg molecules resulting from the binding of a D-state Rydberg electron to a ground state rubidium atom. We show that we can address specific rovibrational molecular states by changing our laser detuning and thus create perfectly aligned axial or antialigned toroidal molecules, in good agreement with our theoretical calculations. Furthermore the influence of the electric field on the Rydberg molecules was investigated, creating novel states which show a different angular dependence and alignment. In the second part of this thesis we excite single D-state Rydberg electrons in a Bose-Einstein condensate. We study the lifetime of these Rydberg electrons, the change of the shape of our condensate and the atom losses in the condensate due to this process. Moreover, we observe quadrupolar shape oscillations of the whole condensate created by the consecutive excitation of Rydberg atoms and compare all results to previous S-state measurements. In the outlook we propose a wide range of further experiments including the proposal of imaging a single electron wavefunction by the imprint of its orbit into the Bose-Einstein condensate.

  1. Many-body physics with alkaline-earth Rydberg lattices

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, R; Nath, R; Pohl, T [Max Planck Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, 01187 Dresden (Germany); Millen, J; Jones, M P A, E-mail: rick@pks.mpg.de [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom)

    2011-09-28

    We explore the prospects for confining alkaline-earth Rydberg atoms in an optical lattice via optical dressing of the secondary core-valence electron. Focussing on the particular case of strontium, we identify experimentally accessible magic wavelengths for simultaneous trapping of ground and Rydberg states. A detailed analysis of relevant loss mechanisms shows that the overall lifetime of such a system is limited only by the spontaneous decay of the Rydberg state, and is not significantly affected by photoionization or autoionization. The van der Waals C{sub 6} coefficients for the Sr(5sns {sup 1}S{sub 0}) Rydberg series are calculated, and we find that the interactions are attractive. Finally we show that the combination of magic-wavelength lattices and attractive interactions could be exploited to generate many-body Greenberger-Horne-Zeilinger states.

  2. Calculation of Rydberg interaction potentials

    DEFF Research Database (Denmark)

    Weber, Sebastian; Tresp, Christoph; Menke, Henri

    2017-01-01

    The strong interaction between individual Rydberg atoms provides a powerful tool exploited in an ever-growing range of applications in quantum information science, quantum simulation and ultracold chemistry. One hallmark of the Rydberg interaction is that both its strength and angular dependence...... for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up...

  3. Rydberg atoms in strong fields

    International Nuclear Information System (INIS)

    Kleppner, D.; Tsimmerman, M.

    1985-01-01

    Experimental and theoretical achievements in studying Rydberg atoms in external fields are considered. Only static (or quasistatic) fields and ''one-electron'' atoms, i.e. atoms that are well described by one-electron states, are discussed. Mainly behaviour of alkali metal atoms in electric field is considered. The state of theoretical investigations for hydrogen atom in magnetic field is described, but experimental data for atoms of alkali metals are presented as an illustration. Results of the latest experimental and theoretical investigations into the structure of Rydberg atoms in strong fields are presented

  4. Quantum information with Rydberg atoms

    DEFF Research Database (Denmark)

    Saffman, Mark; Walker, T.G.; Mølmer, Klaus

    2010-01-01

    Rydberg atoms with principal quantum number n»1 have exaggerated atomic properties including dipole-dipole interactions that scale as n4 and radiative lifetimes that scale as n3. It was proposed a decade ago to take advantage of these properties to implement quantum gates between neutral atom...... of multiqubit registers, implementation of robust light-atom quantum interfaces, and the potential for simulating quantum many-body physics. The advances of the last decade are reviewed, covering both theoretical and experimental aspects of Rydberg-mediated quantum information processing....

  5. Coopetition and manipulation of quantum correlations in Rydberg atoms

    International Nuclear Information System (INIS)

    Fan, Chu-Hui; Yan, Dong; Liu, Yi-Mou; Wu, Jin-Hui

    2017-01-01

    We study the steady-state quantum correlations arising from the atom–field and interatomic interplays in two-level Rydberg atoms coherently driven by an external laser field. Three kinds of quantum correlations, i.e., atom–atom correlation, atom–field entanglement and photon–photon correlation, are simultaneously examined by considering dipole–dipole interactions (DDI) for pairwise Rydberg atoms. They are shown to be closely linked with single and double Rydberg excitations, which can be modulated to work in the blockade or antiblockade regime depending on the driving field frequency, the DDI strength and the Rydberg decay rate. As a result, we obtain strongly correlated atoms and highly antibunching photons (indispensable resources in applications of quantum information processing) intermediated with robust atom–field entanglement. (paper)

  6. Jahn-Teller effect in Rydberg series: A multi-state vibronic coupling problem

    International Nuclear Information System (INIS)

    Staib, A.; Domcke, W.; Sobolewski, A.L.

    1990-01-01

    Two simple limiting cases of Jahn-Teller (JT) coupling in Rydberg states of polyatomic molecules are considered, namely (i) JT coupling in Rydberg orbitals as well as in the ionization continuum (nondegenerate ion core, degenerate Rydberg series) and (ii) JT coupling in the ion core (degenerate ion core, nondegenerate Rydberg series). For both models simple and efficient algorithms for the computation of spectra (dynamical JT effect) are developed. The orbital JT effect is shown to represent a novel type of multi-state vibronic coupling, giving rise to interesting spectroscopic phenomena, among them resonant inter-Rydberg perturbations and JT induced autoionization. Particular attention is paid to the demonstration of the characteristic spectroscopic signatures of the two types of JT coupling in Rydberg states. (orig.)

  7. Rydberg-Stark states of Positronium for atom optics

    International Nuclear Information System (INIS)

    Alonso, A M; Cooper, B S; Deller, A; Hogan, S D; Wall, T E; Cassidy, D B

    2015-01-01

    Positronium atoms were produced in Rydberg states by means of a two-step optical excitation process (1s→2p→nd/ns). The n = 11 Rydberg-Stark manifold has been studied using different laser polarizations providing greater control over the electric dipole moment. (paper)

  8. Optical spectroscopy of rubidium Rydberg atoms with a 297 nm frequency doubled dye laser

    International Nuclear Information System (INIS)

    Becker, Th.; Germann, Th.; Thoumany, P.; Stania, G.; Urbonas, L.; Haensch, T.

    2008-01-01

    Full text: Rydberg atoms have played an important role in atomic physics and optical spectroscopy since many years. Due to their long lifetime and the big dipole matrix element between neighbouring Rydberg levels they are an essential tool in microwave cavity-qed experiments. Ultracold Rydberg gases are a promising candidate for realizing controlled quantum gates in atomic ensembles. In most experiments Rydberg atoms are detected destructively, where the optically excited atoms are first ionized followed by an electronic detection of the ionization products. A Doppler-free purely optical detection was reported in a room temperature cell and in an atomic beam apparatus using the technique of electromagnetically induced transparency. In all these experiments the Rydberg atoms are excited with two lasers in a two-step ladder configuration. Here we show that Doppler-free purely optical spectroscopy is also possible with a one step excitation scheme involving a UV laser at 297 nm. We excite the 85 Rb isotope from the 5S 1/2 ground state to the 63P 3/2 state with a frequency doubled dye laser in a room temperature gas cell without buffer gas. Rydberg transitions are detected by monitoring the absorption of 780 nm laser light which is superimposed on the UV light and resonant with one hyperfine component of the Rubidium D2 line. With these two lasers we realize a V-scheme and utilize the quantum amplification effect due to the different natural lifetimes of the upper levels of the two transitions: an excitation into the 63P level hinders many absorption-emission cycles of the D2 transition and leads to a reduced absorption on that line. We discuss the shape of the observed spectra in the context of electron shelving and EIT experiments. By applying a frequency modulation to the UV laser, we can obtain dispersive signals which can be used to stabilize the laser to a specific Rydberg transition. By shifting the frequency of the 780 nm laser to crossover resonances in the

  9. Theory of long-range interactions for Rydberg states attached to hyperfine-split cores

    Science.gov (United States)

    Robicheaux, F.; Booth, D. W.; Saffman, M.

    2018-02-01

    The theory is developed for one- and two-atom interactions when the atom has a Rydberg electron attached to a hyperfine-split core state. This situation is relevant for some of the rare-earth and alkaline-earth atoms that have been proposed for experiments on Rydberg-Rydberg interactions. For the rare-earth atoms, the core electrons can have a very substantial total angular momentum J and a nonzero nuclear spin I . In the alkaline-earth atoms there is a single (s ) core electron whose spin can couple to a nonzero nuclear spin for odd isotopes. The resulting hyperfine splitting of the core state can lead to substantial mixing between the Rydberg series attached to different thresholds. Compared to the unperturbed Rydberg series of the alkali-metal atoms, the series perturbations and near degeneracies from the different parity states could lead to qualitatively different behavior for single-atom Rydberg properties (polarizability, Zeeman mixing and splitting, etc.) as well as Rydberg-Rydberg interactions (C5 and C6 matrices).

  10. Revivals of Rydberg wave packets

    International Nuclear Information System (INIS)

    Bluhm, R.; Kostelecky, V.A.; Tudose, B.

    1998-01-01

    We examine the revival structure of Rydberg wave packets. These wave packets exhibit initial classical periodic motion followed by a sequence of collapse, fractional (or full) revivals, and fractional (or full) superrevivals. The effects of quantum defects on wave packets in alkali-metal atoms and a squeezed-state description of the initial wave packets are also considered. We then examine the revival structure of Rydberg wave packets in the presence of an external electric field - that is, the revival structure of Stark wave packets. These wave packets have energies that depend on two quantum numbers and exhibit new types of interference behavior

  11. Resonant inelastic x-ray scattering and photoemission measurement of O2: Direct evidence for dependence of Rydberg-valence mixing on vibrational states in O 1s → Rydberg states

    Science.gov (United States)

    Gejo, T.; Oura, M.; Tokushima, T.; Horikawa, Y.; Arai, H.; Shin, S.; Kimberg, V.; Kosugi, N.

    2017-07-01

    High-resolution resonant inelastic x-ray scattering (RIXS) and low-energy photoemission spectra of oxygen molecules have been measured for investigating the electronic structure of Rydberg states in the O 1s → σ* energy region. The electronic characteristics of each Rydberg state have been successfully observed, and new assignments are made for several states. The RIXS spectra clearly show that vibrational excitation is very sensitive to the electronic characteristics because of Rydberg-valence mixing and vibronic coupling in O2. This observation constitutes direct experimental evidence that the Rydberg-valence mixing characteristic depends on the vibrational excitation near the avoided crossing of potential surfaces. We also measured the photoemission spectra of metastable oxygen atoms (O*) from O2 excited to 1s → Rydberg states. The broadening of the 4p Rydberg states of O* has been found with isotropic behavior, implying that excited oxygen molecules undergo dissociation with a lifetime of the order of 10 fs in 1s → Rydberg states.

  12. Scaling laws of Rydberg excitons

    Science.gov (United States)

    Heckötter, J.; Freitag, M.; Fröhlich, D.; Aßmann, M.; Bayer, M.; Semina, M. A.; Glazov, M. M.

    2017-09-01

    Rydberg atoms have attracted considerable interest due to their huge interaction among each other and with external fields. They demonstrate characteristic scaling laws in dependence on the principal quantum number n for features such as the magnetic field for level crossing or the electric field of dissociation. Recently, the observation of excitons in highly excited states has allowed studying Rydberg physics in cuprous oxide crystals. Fundamentally different insights may be expected for Rydberg excitons, as the crystal environment and associated symmetry reduction compared to vacuum give not only optical access to many more states within an exciton multiplet but also extend the Hamiltonian for describing the exciton beyond the hydrogen model. Here we study experimentally and theoretically the scaling of several parameters of Rydberg excitons with n , for some of which we indeed find laws different from those of atoms. For others we find identical scaling laws with n , even though their origin may be distinctly different from the atomic case. At zero field the energy splitting of a particular multiplet n scales as n-3 due to crystal-specific terms in the Hamiltonian, e.g., from the valence band structure. From absorption spectra in magnetic field we find for the first crossing of levels with adjacent principal quantum numbers a Br∝n-4 dependence of the resonance field strength, Br, due to the dominant paramagnetic term unlike for atoms for which the diamagnetic contribution is decisive, resulting in a Br∝n-6 dependence. By contrast, the resonance electric field strength shows a scaling as Er∝n-5 as for Rydberg atoms. Also similar to atoms with the exception of hydrogen we observe anticrossings between states belonging to multiplets with different principal quantum numbers at these resonances. The energy splittings at the avoided crossings scale roughly as n-4, again due to crystal specific features in the exciton Hamiltonian. The data also allow us to

  13. Rydberg atoms ionization by microwave field and electromagnetic pulses

    International Nuclear Information System (INIS)

    Kaulakys, B.; Vilutis, G.

    1995-01-01

    A simple theory of the Rydberg atoms ionization by electromagnetic pulses and microwave field is presented. The analysis is based on the scale transformation which reduces the number of parameters and reveals the functional dependencies of the processes. It is shown that the observed ionization of Rydberg atoms by subpicosecond electromagnetic pulses scale classically. The threshold electric field required to ionise a Rydberg state may be simply evaluated in the photonic basis approach for the quantum dynamics or from the multiphoton ionization theory

  14. Changes in liquid water alter nutrient bioavailability and gas diffusion in frozen antarctic soils contaminated with petroleum hydrocarbons.

    Science.gov (United States)

    Harvey, Alexis Nadine; Snape, Ian; Siciliano, Steven Douglas

    2012-02-01

    Bioremediation has been used to remediate petroleum hydrocarbon (PHC)-contaminated sites in polar regions; however, limited knowledge exists in understanding how frozen conditions influence factors that regulate microbial activity. We hypothesized that increased liquid water (θ(liquid) ) would affect nutrient supply rates (NSR) and gas diffusion under frozen conditions. If true, management practices that increase θ(liquid) should also increase bioremediation in polar soils by reducing nutrient and oxygen limitations. Influence of θ(liquid) on NSR was determined using diesel-contaminated soil (0-8,000 mg kg(-1)) from Casey Station, Antarctica. The θ(liquid) was altered between 0.007 and 0.035 cm(3) cm(-3) by packing soil cores at different bulk densities. The nutrient supply rate of NH 4+ and NO 3-, as well as gas diffusion coefficient, D(s), were measured at two temperatures, 21°C and -5°C, to correct for bulk density effects. Freezing decreased NSR of both NH 4+ and NO 3-, with θ(liquid) linked to nitrate and ammonia NSR in frozen soil. Similarly for D(s), decreases due to freezing were much more pronounced in soils with low θ(liquid) compared to soils with higher θ(liquid) contents. Additional studies are needed to determine the relationship between degradation rates and θ(liquid) under frozen conditions. Copyright © 2011 SETAC.

  15. Contaminant-State Broadening Mechanism in a Driven Dissipative Rydberg System

    Science.gov (United States)

    Porto, J. V.

    2017-04-01

    The strong interactions in Rydberg atoms make them an ideal system for the study of correlated many-body physics, both in the presence and absence of dissipation. Using such highly excited atomic states requires addressing challenges posed by the dense spectrum of Rydberg levels, the detrimental effects of spontaneous emission, and strong interactions. A full understanding of the scope and limitations of many Rydberg-based proposals requires simultaneously including these effects, which typically cannot be described by a mean-field treatment due to correlations in the quantum coherent and dissipative processes. We study a driven, dissipative system of Rydberg atoms in a 3D optical lattice, and observe substantial deviation from single-particle excitation rates, both on and off resonance. The observed broadened spectra cannot be explained by van der Waals interactions or a mean-field treatment of the system. Based on the magnitude of the broadening and the scaling with density and two-photon Rabi frequency, we attribute these effects to unavoidable blackbody-induced transitions to nearby Rydberg states of opposite parity, which have large, resonant dipole-dipole interactions with the state of interest. Even at low densities of Rydberg atoms, uncontrolled production of atoms in other states significantly modifies the energy levels of the remaining atoms. These off-diagonal exchange interactions result in complex many-body states of the system and have implications for off-resonant Rydberg dressing proposals. This work was partially supported by the ARL-CDQI program.

  16. Theoretical Analysis of Rydberg and Autoionizing State Spectra of Antimony

    Institute of Scientific and Technical Information of China (English)

    Shuang-Fei Lv; Ruohong Li; Feng-Dong Jia; Xiao-Kang Li; Jens Lassen; Zhi-Ping Zhong

    2017-01-01

    We calculate the Rydberg and autoionization Rydberg spectra of antimony (Sb) from first principles by relativistic multichannel theory within the framework of multichannel quantum defect theory.Our calculation can be used to classify and assign the atomic states described in recently reported three Rydberg series and four autoionizing states.The perturbation effects on line intensity,variation and line profile are discussed.Assignments of the perturber states and autoionizing states are presented.

  17. Strong enhancement of Penning ionization for asymmetric atom pairs in cold Rydberg gases: the Tom and Jerry effect

    KAUST Repository

    Efimov, D K

    2016-05-18

    We consider Penning ionization of Rydberg atom pairs as an Auger-type process induced by the dipole-dipole interaction and employ semiclassical formulae for dipole transitions to calculate the autoionization width as a function of the principal quantum numbers, n d, n i, of both atoms. While for symmetric atom pairs with the well-known increase of the autoionization width with increasing n 0 is obtained, the result for asymmetric pairs is counterintuitive - for a fixed n i of the ionizing atom of the pair, the autoionization width strongly increases with decreasing n d of the de-excited atom. For H Rydberg atoms this increase reaches two orders of magnitude at the maximum of the n d dependence, and the same type of counterintuitive behavior is exhibited also by Na, Rb and Cs atoms. This is a purely quantum-mechanical effect, which points towards existence of optimal (we call them \\'Tom\\' and \\'Jerry\\' for \\'big\\' and \\'small\\') pairs of Rydberg atoms with respect to autoionization efficiency. Building on the model of population redistribution in cold Rydberg gases proposed in [1], we demonstrate that population evolution following the initial laser excitation of Rydberg atoms in state n 0 would eventually lead to the formation of such Tom-Jerry pairs with which feature autoionization widths that are enhanced by several orders of magnitude compared to that of two atoms in the initial laser-excited state n 0. We also show that in the high-density regime of cold Rydberg gas experiments the ionization rate of Tom-Jerry pairs can be substantially larger than the blackbody radiation-induced photoionization rate. © 2016 IOP Publishing Ltd.

  18. The role of high Rydberg states in the generation of negative ions in negative-ion discharges

    International Nuclear Information System (INIS)

    Hiskes, J.R.

    1995-01-01

    The generation of substantial yields of H - ions in a laser excited H 2 gas has been reported by Pinnaduwage and Christoforu. These H - yields have been attributed to (2 + 1) REMP photoexcitation processes leading to dissociative attachment of doubly-excited or superexcited states (SES), or dissociative attachment of high Rydberg product states. The new feature of these experiments is the implied large dissociative attachment rates, of order 10 -6 cm 3 sec -1 , values that are orders-of-magnitude larger than the dissociative attachment of the vibrationally excited levels of the ground electronic state. While these laser excitations are not directly applicable to a hydrogen negative-ion discharge, the implication of large dissociative attachment rates to the high Rydberg states may affect both the total negative-ion density and the interpretation of discharge performance. Within the discharge energetic electrons will collisionally excite the higher Rydberg states, and the relative contribution of the dissociative attachment of these states when compared with the dissociative attachment to the ground state vibrational levels, is the topic of this paper

  19. Self-interaction corrected density functional calculations of molecular Rydberg states

    International Nuclear Information System (INIS)

    Gudmundsdóttir, Hildur; Zhang, Yao; Weber, Peter M.; Jónsson, Hannes

    2013-01-01

    A method is presented for calculating the wave function and energy of Rydberg excited states of molecules. A good estimate of the Rydberg state orbital is obtained using ground state density functional theory including Perdew-Zunger self-interaction correction and an optimized effective potential. The total energy of the excited molecule is obtained using the Delta Self-Consistent Field method where an electron is removed from the highest occupied orbital and placed in the Rydberg orbital. Results are presented for the first few Rydberg states of NH 3 , H 2 O, H 2 CO, C 2 H 4 , and N(CH 3 ) 3 . The mean absolute error in the energy of the 33 molecular Rydberg states presented here is 0.18 eV. The orbitals are represented on a real space grid, avoiding the dependence on diffuse atomic basis sets. As in standard density functional theory calculations, the computational effort scales as NM 2 where N is the number of orbitals and M is the number of grid points included in the calculation. Due to the slow scaling of the computational effort with system size and the high level of parallelism in the real space grid approach, the method presented here makes it possible to estimate Rydberg electron binding energy in large molecules

  20. Spectroscopy of strontium Rydberg states using electromagnetically induced transparency

    International Nuclear Information System (INIS)

    Mauger, S; Millen, J; Jones, M P A

    2007-01-01

    We report on the all-optical detection of Rydberg states in an effusive atomic beam of strontium atoms using electromagnetically induced transparency (EIT). Using narrow-linewidth CW lasers we obtain an EIT linewidth of 5 MHz. To illustrate the high spectroscopic resolution offered by this method, we have measured isotope shifts of the 5s18d 1 D 2 and 5s19s 1 S 0 Rydberg states. This technique could be applied to high-resolution, non-destructive measurements of ultra-cold Rydberg gases and plasmas. (fast track communication)

  1. Stimulated adiabatic passage in a dissipative ensemble of atoms with strong Rydberg-state interactions

    DEFF Research Database (Denmark)

    Petrosyan, David; Molmer, Klaus

    2013-01-01

    We study two-photon excitation of Rydberg states of atoms under stimulated adiabatic passage with delayed laser pulses. We find that the combination of strong interaction between the atoms in Rydberg state and the spontaneous decay of the intermediate exited atomic state leads to the Rydberg exci...... for deterministic creation and, possibly, extraction of Rydberg atoms or ions one at a time. The sympathetic monitoring via decay of ancilla particles may find wider applications for state preparation and probing of interactions in dissipative many-body systems.......We study two-photon excitation of Rydberg states of atoms under stimulated adiabatic passage with delayed laser pulses. We find that the combination of strong interaction between the atoms in Rydberg state and the spontaneous decay of the intermediate exited atomic state leads to the Rydberg...

  2. Metastability and Rydberg states of triatomic hydrogen

    International Nuclear Information System (INIS)

    Helm, H.

    1991-01-01

    The np,nd and nf Rydberg series of H 3 have been studied by one- or two-photon excitation from the lowest metastable state of H 3 :B2p 2 A 2 ''. The lifetime of the metastable state has been measured and the influence of an external electric field on the Rydberg states has been studied under both aspects of dynamics (field-ionization and field-induced predissociation) and structure (Strak effect)

  3. Robustness of high-fidelity Rydberg gates with single-site addressability

    Science.gov (United States)

    Goerz, Michael H.; Halperin, Eli J.; Aytac, Jon M.; Koch, Christiane P.; Whaley, K. Birgitta

    2014-09-01

    Controlled-phase (cphase) gates can be realized with trapped neutral atoms by making use of the Rydberg blockade. Achieving the ultrahigh fidelities required for quantum computation with such Rydberg gates, however, is compromised by experimental inaccuracies in pulse amplitudes and timings, as well as by stray fields that cause fluctuations of the Rydberg levels. We report here a comparative study of analytic and numerical pulse sequences for the Rydberg cphase gate that specifically examines the robustness of the gate fidelity with respect to such experimental perturbations. Analytical pulse sequences of both simultaneous and stimulated Raman adiabatic passage (STIRAP) are found to be at best moderately robust under these perturbations. In contrast, optimal control theory is seen to allow generation of numerical pulses that are inherently robust within a predefined tolerance window. The resulting numerical pulse shapes display simple modulation patterns and can be rationalized in terms of an interference between distinct two-photon Rydberg excitation pathways. Pulses of such low complexity should be experimentally feasible, allowing gate fidelities of order 99.90-99.99% to be achievable under realistic experimental conditions.

  4. Strong enhancement of Penning ionization for asymmetric atom pairs in cold Rydberg gases: the Tom and Jerry effect

    KAUST Repository

    Efimov, D K; Miculis, K; Bezuglov, N N; Ekers, Aigars

    2016-01-01

    with which feature autoionization widths that are enhanced by several orders of magnitude compared to that of two atoms in the initial laser-excited state n 0. We also show that in the high-density regime of cold Rydberg gas experiments the ionization rate

  5. Transient localization in the kicked Rydberg atom

    OpenAIRE

    Persson, E.; Fürthauer, S.; Wimberger, S.; Burgdörfer, J.

    2006-01-01

    We investigate the long-time limit of quantum localization of the kicked Rydberg atom. The kicked Rydberg atom is shown to possess in addition to the quantum localization time $\\tau_L$ a second cross-over time $t_D$ where quantum dynamics diverges from classical dynamics towards increased instability. The quantum localization is shown to vanish as either the strength of the kicks at fixed principal quantum number or the quantum number at fixed kick strength increases. The survival probability...

  6. High resolution studies of barium Rydberg states

    International Nuclear Information System (INIS)

    Eliel, E.R.

    1982-01-01

    The subtle structure of Rydberg states of barium with orbital angular momentum 0, 1, 2 and 3 is investigated. Some aspects of atomic theory for a configuration with two valence electrons are reviewed. The Multi Channel Quantum Defect Theory (MQDT) is concisely introduced as a convenient way to describe interactions between Rydberg series. Three high-resolution UV studies are presented. The first two, presenting results on a transition in indium and europium serve as an illustration of the frequency doubling technique. The third study is of hyperfine structure and isotope shifts in low-lying p states in Sr and Ba. An extensive study of the 6snp and 6snf Rydberg states of barium is presented with particular emphasis on the 6snf states. It is shown that the level structure cannot be fully explained with the model introduced earlier. Rather an effective two-body spin-orbit interaction has to be introduced to account for the observed splittings, illustrating that high resolution studies on Rydberg states offer an unique opportunity to determine the importance of such effects. Finally, the 6sns and 6snd series are considered. The hyperfine induced isotope shift in the simple excitation spectra to 6sns 1 S 0 is discussed and attention is paid to series perturbers. It is shown that level mixing parameters can easily be extracted from the experimental data. (Auth.)

  7. Many-body quantum simulation with Rydberg atoms and ions

    International Nuclear Information System (INIS)

    Mueller, M.

    2010-01-01

    This thesis presents my work that is located at the interface between the fields of atomic physics, quantum optics and quantum information. The work was performed at the Institute of Theoretical Physics of the University of Innsbruck and the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences under the supervision of Prof. Peter Zoller. The main topic of this thesis is the investigation of new schemes for quantum simulation of interacting many-body systems. The thesis is divided into three parts, which cover my work on i) chains of trapped Rydberg ions ii) quantum information processing and simulation with Rydberg atoms and iii) quantum simulation with ground state ions. The first part of this thesis is concerned with the study of Rydberg ions trapped in a linear Paul trap. The properties of ionic Rydberg states in the presence of the static and time-dependent electric trapping fields are investigated. First it is analyzed under which conditions laser-excited Rydberg ions can be trapped in a stable configuration. Furthermore, it is shown that strong dipole-dipole interactions among the ions can be achieved by microwave dressing fields. These interactions can give rise to dynamics of Rydberg excitations through the ion crystal, which take place on a nanosecond timescale and can be described by effective spin-models. In addition, it is discussed how to achieve fast two-qubit entangling gates between pairs of Rydberg ions. In the second part of this thesis, novel possibilities of using neutral Rydberg atoms for quantum-information processing and quantum simulation are investigated. A new scheme for a multi-atom quantum gate is proposed and theoretically analyzed. This parallelized gate allows one to entangle a mesoscopic ensemble of atoms with a single control atom in a single step, with high fidelity and on a microsecond time scale. The operation relies on strong and long-ranged interactions between Rydberg atoms triggering a

  8. Nonadiabatic holonomic quantum computation using Rydberg blockade

    Science.gov (United States)

    Kang, Yi-Hao; Chen, Ye-Hong; Shi, Zhi-Cheng; Huang, Bi-Hua; Song, Jie; Xia, Yan

    2018-04-01

    In this paper, we propose a scheme for realizing nonadiabatic holonomic computation assisted by two atoms and the shortcuts to adiabaticity (STA). The blockade effect induced by strong Rydberg-mediated interaction between two Rydberg atoms provides us the possibility to simplify the dynamics of the system, and the STA helps us design pulses for implementing the holonomic computation with high fidelity. Numerical simulations show the scheme is noise immune and decoherence resistant. Therefore, the current scheme may provide some useful perspectives for realizing nonadiabatic holonomic computation.

  9. Ionization of Rydberg atoms by the kicks of half-cycle pulses

    Indian Academy of Sciences (India)

    Rydberg atom; half-cycle pulses; ionization; quantum mechanical model. ... packet which represents a non-stationary quantum state formed by coherent ...... Wetzels, Impulsive interactions of half cycle pulse radiation with Rydberg atoms, Ph.D.

  10. Molecular Rydberg transitions in carbon monoxide

    International Nuclear Information System (INIS)

    Fock, J.H.; Guertler, P.; Koch, E.E.

    1979-10-01

    The linear correlation between the term value and ionization energy for molecular Rydberg transitions is tested for the sequence of isoelectronic molecules BF, CO and N 2 based on a new measurement of the absorption spectrum of CO and data for BF and N 2 . For the npsigma series and npπ series converging on the first ionization potential, we find an excellent linear behavior (within 10 meV) corroborating (I) the correlation and (II) the individual assignments. For Rydberg series leading to the A 2 DELTA and B 2 EPSILON + states, where no data for BF are available, a comparison of term values for CO and N 2 is presented. (orig.)

  11. Microscopic Characterization of Scalable Coherent Rydberg Superatoms

    Directory of Open Access Journals (Sweden)

    Johannes Zeiher

    2015-08-01

    Full Text Available Strong interactions can amplify quantum effects such that they become important on macroscopic scales. Controlling these coherently on a single-particle level is essential for the tailored preparation of strongly correlated quantum systems and opens up new prospects for quantum technologies. Rydberg atoms offer such strong interactions, which lead to extreme nonlinearities in laser-coupled atomic ensembles. As a result, multiple excitation of a micrometer-sized cloud can be blocked while the light-matter coupling becomes collectively enhanced. The resulting two-level system, often called a “superatom,” is a valuable resource for quantum information, providing a collective qubit. Here, we report on the preparation of 2 orders of magnitude scalable superatoms utilizing the large interaction strength provided by Rydberg atoms combined with precise control of an ensemble of ultracold atoms in an optical lattice. The latter is achieved with sub-shot-noise precision by local manipulation of a two-dimensional Mott insulator. We microscopically confirm the superatom picture by in situ detection of the Rydberg excitations and observe the characteristic square-root scaling of the optical coupling with the number of atoms. Enabled by the full control over the atomic sample, including the motional degrees of freedom, we infer the overlap of the produced many-body state with a W state from the observed Rabi oscillations and deduce the presence of entanglement. Finally, we investigate the breakdown of the superatom picture when two Rydberg excitations are present in the system, which leads to dephasing and a loss of coherence.

  12. Transient localization in the kicked Rydberg atom

    International Nuclear Information System (INIS)

    Persson, Emil; Fuerthauer, S.; Burgdoerfer, J.; Wimberger, S.

    2006-01-01

    We investigate the long-time limit of quantum localization of the kicked Rydberg atom. The kicked Rydberg atom is shown to possess in addition to the quantum localization time τ L a second crossover time t D where quantum dynamics diverges from classical dynamics towards increased instability. The quantum localization is shown to vanish as either the strength of the kicks at fixed principal quantum number or the quantum number at fixed kick strength increases. The survival probability as a function of frequency in the transient localization regime τ L D is characterized by highly irregular, fractal-like fluctuations

  13. Interactions of circular Rydberg atoms with charged particles

    International Nuclear Information System (INIS)

    Wang, J.

    1994-01-01

    Recent progress in experimental cross-field techniques has made it possible to produce oriented Rydberg atoms of any angular momentum l within a given n manifold. The largest angular momentum state l max = n - 1 of a given n manifold is of particular interest because of its semiclassical properties for n much-gt 1. The corresponding classical Kepler orbit is circular with highly localized phase space distribution. The circular Rydberg atoms afford the opportunity to study various interactions in the semiclassical regime. The authors report electron capture from circular Rydberg atoms by protons and positrons at speeds comparable to the electron orbital speed. They find orientation dependent, novel peak structures for both protons and positrons in the angular scattering of the particles. The structures may be understood in terms of quasi Thomas double scattering mechanism for capture. Other related aspects including final state population and orientation indulged scattering asymmetry will also be discussed

  14. Observation of pendular butterfly Rydberg molecules

    Science.gov (United States)

    Niederprüm, Thomas; Thomas, Oliver; Eichert, Tanita; Lippe, Carsten; Pérez-Ríos, Jesús; Greene, Chris H.; Ott, Herwig

    2016-01-01

    Engineering molecules with a tunable bond length and defined quantum states lies at the heart of quantum chemistry. The unconventional binding mechanism of Rydberg molecules makes them a promising candidate to implement such tunable molecules. A very peculiar type of Rydberg molecules are the so-called butterfly molecules, which are bound by a shape resonance in the electron–perturber scattering. Here we report the observation of these exotic molecules and employ their exceptional properties to engineer their bond length, vibrational state, angular momentum and orientation in a small electric field. Combining the variable bond length with their giant dipole moment of several hundred Debye, we observe counter-intuitive molecules which locate the average electron position beyond the internuclear distance. PMID:27703143

  15. Correlated Photon Emission from Multiatom Rydberg Dark States

    DEFF Research Database (Denmark)

    Pritchard, J.D.; Adams, C.S.; Mølmer, Klaus

    2012-01-01

    We consider three-level atoms driven by two resonant light fields in a ladder scheme where the upper level is a highly excited Rydberg state. We show that the dipole-dipole interactions between Rydberg excited atoms prevents the formation of single particle dark states and leads to strongly corre...... correlated photon pairs from atoms separated by distances large compared to the emission wavelength. For a pair of atoms, this enables realization of an efficient photon-pair source with on average one pair every 30 μs....

  16. Non-adiabatic quantum state preparation and quantum state transport in chains of Rydberg atoms

    Science.gov (United States)

    Ostmann, Maike; Minář, Jiří; Marcuzzi, Matteo; Levi, Emanuele; Lesanovsky, Igor

    2017-12-01

    Motivated by recent progress in the experimental manipulation of cold atoms in optical lattices, we study three different protocols for non-adiabatic quantum state preparation and state transport in chains of Rydberg atoms. The protocols we discuss are based on the blockade mechanism between atoms which, when excited to a Rydberg state, interact through a van der Waals potential, and rely on single-site addressing. Specifically, we discuss protocols for efficient creation of an antiferromagnetic GHZ state, a class of matrix product states including a so-called Rydberg crystal and for the state transport of a single-qubit quantum state between two ends of a chain of atoms. We identify system parameters allowing for the operation of the protocols on timescales shorter than the lifetime of the Rydberg states while yielding high fidelity output states. We discuss the effect of positional disorder on the resulting states and comment on limitations due to other sources of noise such as radiative decay of the Rydberg states. The proposed protocols provide a testbed for benchmarking the performance of quantum information processing platforms based on Rydberg atoms.

  17. Semiclassical calculation of ionisation rate for Rydberg helium atoms in an electric field

    International Nuclear Information System (INIS)

    Wang De-Hua

    2011-01-01

    The ionisation of Rydberg helium atoms in an electric field above the classical ionisation threshold has been examined using the semiclassical method, with particular emphasis on discussing the influence of the core scattering on the escape dynamics of electrons. The results show that the Rydberg helium atoms ionise by emitting a train of electron pulses. Unlike the case of the ionisation of Rydberg hydrogen atom in parallel electric and magnetic fields, where the pulses of the electron are caused by the external magnetic field, the pulse trains for Rydberg helium atoms are created through core scattering. Each peak in the ionisation rate corresponds to the contribution of one core-scattered combination trajectory. This fact further illustrates that the ionic core scattering leads to the chaotic property of the Rydberg helium atom in external fields. Our studies provide a simple explanation for the escape dynamics in the ionisation of nonhydrogenic atoms in external fields. (atomic and molecular physics)

  18. Radio-frequency-modulated Rydberg states in a vapor cell

    Science.gov (United States)

    Miller, S. A.; Anderson, D. A.; Raithel, G.

    2016-05-01

    We measure strong radio-frequency (RF) electric fields using rubidium Rydberg atoms prepared in a room-temperature vapor cell as field sensors. Electromagnetically induced transparency is employed as an optical readout. We RF-modulate the 60{{{S}}}1/2 and 58{{{D}}}5/2 Rydberg states with 50 and 100 MHz fields, respectively. For weak to moderate RF fields, the Rydberg levels become Stark-shifted, and sidebands appear at even multiples of the driving frequency. In high fields, the adjacent hydrogenic manifold begins to intersect the shifted levels, providing rich spectroscopic structure suitable for precision field measurements. A quantitative description of strong-field level modulation and mixing of S and D states with hydrogenic states is provided by Floquet theory. Additionally, we estimate the shielding of DC electric fields in the interior of the glass vapor cell.

  19. Cavity electromagnetically induced transparency with Rydberg atoms

    Science.gov (United States)

    Bakar Ali, Abu; Ziauddin

    2018-02-01

    Cavity electromagnetically induced transparency (EIT) is revisited via the input probe field intensity. A strongly interacting Rydberg atomic medium ensemble is considered in a cavity, where atoms behave as superatoms (SAs) under the dipole blockade mechanism. Each atom in the strongly interacting Rydberg atomic medium (87 Rb) follows a three-level cascade atomic configuration. A strong control and weak probe field are employed in the cavity with the ensemble of Rydberg atoms. The features of the reflected and transmitted probe light are studied under the influence of the input probe field intensity. A transparency peak (cavity EIT) is revealed at a resonance condition for small values of input probe field intensity. The manipulation of the cavity EIT is reported by tuning the strength of the input probe field intensity. Further, the phase and group delay of the transmitted and reflected probe light are studied. It is found that group delay and phase in the reflected light are negative, while for the transmitted light they are positive. The magnitude control of group delay in the transmitted and reflected light is investigated via the input probe field intensity.

  20. Rydberg energies using excited state density functional theory

    International Nuclear Information System (INIS)

    Cheng, C.-L.; Wu Qin; Van Voorhis, Troy

    2008-01-01

    We utilize excited state density functional theory (eDFT) to study Rydberg states in atoms. We show both analytically and numerically that semilocal functionals can give quite reasonable Rydberg energies from eDFT, even in cases where time dependent density functional theory (TDDFT) fails catastrophically. We trace these findings to the fact that in eDFT the Kohn-Sham potential for each state is computed using the appropriate excited state density. Unlike the ground state potential, which typically falls off exponentially, the sequence of excited state potentials has a component that falls off polynomially with distance, leading to a Rydberg-type series. We also address the rigorous basis of eDFT for these systems. Perdew and Levy have shown using the constrained search formalism that every stationary density corresponds, in principle, to an exact stationary state of the full many-body Hamiltonian. In the present context, this means that the excited state DFT solutions are rigorous as long as they deliver the minimum noninteracting kinetic energy for the given density. We use optimized effective potential techniques to show that, in some cases, the eDFT Rydberg solutions appear to deliver the minimum kinetic energy because the associated density is not pure state v-representable. We thus find that eDFT plays a complementary role to constrained DFT: The former works only if the excited state density is not the ground state of some potential while the latter applies only when the density is a ground state density.

  1. Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

    Science.gov (United States)

    Davtyan, D.; Machluf, S.; Soudijn, M. L.; Naber, J. B.; van Druten, N. J.; van Linden van den Heuvell, H. B.; Spreeuw, R. J. C.

    2018-02-01

    Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than 0.2 V /cm at 78 μ m from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.

  2. Effect of storage duration on frozen inoculum to be used for the in vitro gas production technique in rabbit

    Directory of Open Access Journals (Sweden)

    Antonino Nizza

    2010-01-01

    Full Text Available The present study aimed to investigate the effect of storage duration of frozen inoculum on fermentation parametersobtained with the in vitro gas production technique. Two non-predigested diets differing in chemical composition andespecially crude fibre content (low fibre diet: 13.8%; high-fibre diet: 22.6% were ground to pass a 1 mm screen andsubjected to fermentation with the same inoculum frozen for different periods: after 1 month (inoculum 1, after 2months (inoculum 2 and after 3 months (inoculum 3. The inoculum used was obtained from the caecal content of 75-day-old NZW rabbits. After defrosting, the caecal content was diluted with the medium 1:1 (V/V and squeezed throughsix layers of gauze to obtain the inoculum. The substrate affected several fermentation parameters. In particular, thehigh-fibre diet had lower potential and cumulative gas production (A = ml/g 220 vs 256; P vs 221; P acids (mmol/g 56.2 vs 49.8; P P values of degraded organic matter (62.4%, 62.7% and 62.7% respectively for inocula 1, 2 and 3 and similarproduction of VFA (54.0, 52.2 and 52.8 mmol/g, respectively for inocula 1, 2 and 3. This research showed it is possibleto use frozen inoculum for at least 3 months and in this time interval obtain the same parameters of in vitro fermentation.

  3. High-fidelity Rydberg quantum gate via a two-atom dark state

    DEFF Research Database (Denmark)

    Petrosyan, David; Motzoi, Felix; Saffman, Mark

    2017-01-01

    We propose a two-qubit gate for neutral atoms in which one of the logical state components adiabatically follows a two-atom dark state formed by the laser coupling to a Rydberg state and a strong, resonant dipole-dipole exchange interaction between two Rydberg excited atoms. Our gate exhibits...

  4. Electromagnetically induced grating with Rydberg atoms

    Science.gov (United States)

    Asghar, Sobia; Ziauddin, Qamar, Shahid; Qamar, Sajid

    2016-09-01

    We present a scheme to realize electromagnetically induced grating in an ensemble of strongly interacting Rydberg atoms, which act as superatoms due to the dipole blockade mechanism. The ensemble of three-level cold Rydberg-dressed (87Rb) atoms follows a cascade configuration where a strong standing-wave control field and a weak probe pulse are employed. The diffraction intensity is influenced by the strength of the probe intensity, the control field strength, and the van der Waals (vdW) interaction. It is noticed that relatively large first-order diffraction can be obtained for low-input intensity with a small vdW shift and a strong control field. The scheme can be considered as an amicable solution to realize the atomic grating at the microscopic level, which can provide background- and dark-current-free diffraction.

  5. Wave-packet approach to Rydberg resonances in dissociative recombination

    International Nuclear Information System (INIS)

    Morisset, Sabine; Pichl, Lukas; Orel, Ann E.; Schneider, Ioan F.

    2007-01-01

    We report the time-dependent approach to resonant electron capture into Rydberg states in collisions with molecular cations at low impact energy, as an alternative to the method based on multichannel quantum defect theory (MQDT), and present the results for the HD + ion. The propagation of the initial wave function on 13 Rydberg states (besides one valence state) correctly describes the indirect dissociative recombination mechanism in the time domain. Notably, the nonlocal coupling operator between the ionization and dissociation channels is accounted for in the indirect process, extending previous work on the case of direct coupling. The present approach compares to the MQDT framework with remarkable precision: resonant structures in the cross section correctly emerge from the wave-packet propagation; the time-dependent result also forms a cross section envelope for the dense series of ultrafine MQDT resonances corresponding to the quasicontinuous part of the Rydberg state manifold

  6. Many-body dynamics of holes in a driven, dissipative spin chain of Rydberg superatoms

    Science.gov (United States)

    Letscher, Fabian; Petrosyan, David; Fleischhauer, Michael

    2017-11-01

    Strong, long-range interactions between atoms in high-lying Rydberg states can suppress multiple Rydberg excitations within a micron-sized trapping volume and yield sizable Rydberg level shifts at larger distances. Ensembles of atoms in optical microtraps then form Rydberg superatoms with collectively enhanced transition rates to the singly excited state. These superatoms can represent mesoscopic, strongly interacting spins. We study a regular array of such effective spins driven by a laser field tuned to compensate the interaction-induced level shifts between neighboring superatoms. During the initial transient, a few excited superatoms seed a cascade of resonantly facilitated excitation of large clusters of superatoms. Due to spontaneous decay, the system then relaxes to the steady state having nearly universal Rydberg excitation density {ρ }{{R}}=2/3. This state is characterized by highly non-trivial equilibrium dynamics of quasi-particles—excitation holes in the lattice of Rydberg excited superatoms. We derive an effective many-body model that accounts for hole mobility as well as continuous creation and annihilation of holes upon collisions with each other. We find that holes exhibit a nearly incompressible liquid phase with highly sub-Poissonian number statistics and finite-range density-density correlations.

  7. Dynamics of Rydberg atom lattices in the presence of noise and dissipation

    International Nuclear Information System (INIS)

    Abdussalam, Wildan

    2017-01-01

    The work presented in this dissertation concerns dynamics of Rydberg atom lattices in the presence of noise and dissipation. Rydberg atoms possess a number of exaggerated properties, such as a strong van der Waals interaction. The interplay of that interaction, coherent driving and decoherence leads to intriguing non-equilibrium phenomena. Here, we study the non-equilibrium physics of driven atom lattices in the presence of decoherence caused by either laser phase noise or strong decay. In the first case, we compare between global and local noise and explore their effect on the number of excitations and the full counting statistics. We find that both types of noise give rise to a characteristic distribution of the Rydberg excitation number. The main method employed is the Langevin equation but for the sake of efficiency in certain regimes, we use a Markovian master equation and Monte Carlo rate equations, respectively. In the second case, we consider dissipative systems with more general power-law interactions. We determine the phase diagram in the steady state and analyse its generation dynamics using Monte Carlo rate equations. In contrast to nearest-neighbour models, there is no transition to long-range-ordered phases for realistic interactions and resonant driving. Yet, for finite laser detunings, we show that Rydberg atom lattices can undergo a dissipative phase transition to a long-range-ordered antiferromagnetic phase. We identify the advantages of Monte Carlo rate equations over mean field predictions. Having studied the dynamics of Rydberg atom lattices, we study an application of the strong interactions in such systems for quantum information processing. We investigate the coherent exchange of a single photon between a superconducting microwave cavity and a lattice of strongly interacting Rydberg atoms in the presence of local electric field fluctuations plaguing the cavity surface. We show that despite the increased sensitivity of Rydberg states to

  8. Dynamics of Rydberg atom lattices in the presence of noise and dissipation

    Energy Technology Data Exchange (ETDEWEB)

    Abdussalam, Wildan

    2017-08-07

    The work presented in this dissertation concerns dynamics of Rydberg atom lattices in the presence of noise and dissipation. Rydberg atoms possess a number of exaggerated properties, such as a strong van der Waals interaction. The interplay of that interaction, coherent driving and decoherence leads to intriguing non-equilibrium phenomena. Here, we study the non-equilibrium physics of driven atom lattices in the presence of decoherence caused by either laser phase noise or strong decay. In the first case, we compare between global and local noise and explore their effect on the number of excitations and the full counting statistics. We find that both types of noise give rise to a characteristic distribution of the Rydberg excitation number. The main method employed is the Langevin equation but for the sake of efficiency in certain regimes, we use a Markovian master equation and Monte Carlo rate equations, respectively. In the second case, we consider dissipative systems with more general power-law interactions. We determine the phase diagram in the steady state and analyse its generation dynamics using Monte Carlo rate equations. In contrast to nearest-neighbour models, there is no transition to long-range-ordered phases for realistic interactions and resonant driving. Yet, for finite laser detunings, we show that Rydberg atom lattices can undergo a dissipative phase transition to a long-range-ordered antiferromagnetic phase. We identify the advantages of Monte Carlo rate equations over mean field predictions. Having studied the dynamics of Rydberg atom lattices, we study an application of the strong interactions in such systems for quantum information processing. We investigate the coherent exchange of a single photon between a superconducting microwave cavity and a lattice of strongly interacting Rydberg atoms in the presence of local electric field fluctuations plaguing the cavity surface. We show that despite the increased sensitivity of Rydberg states to

  9. Rydberg-state reionization of multiply charged ions escaping from solid surfaces

    International Nuclear Information System (INIS)

    Nedeljkovic, Lj.D.; Nedeljkovic, N.N.

    2003-01-01

    Reionization rates of Rydberg states (n>>1 and l=0, 1, and 2) of multiply charged ionic projectiles escaping solid surfaces are calculated. These rates are obtained in an analytic form as a function of the ion-surface distance R. A phenomenological model of the reionization process, based on two-state quantum dynamics, is adopted for the vicinity of the potential barrier top. The results of calculations show that ionization rates for different Rydberg states are strictly localized and relatively separated. Universality of the reionization rate as a function of the scaling parameter α, describing the turning point configurations, is demonstrated. The reionization is discussed within the framework of a nonresonant population-reionization process at intermediate ionic velocities (v∼1 a.u.). The influence of reionization on the population of ionic Rydberg states is expressed in terms of a renormalized neutralization rate. It is demonstrated that the reionization effect significantly changes the population curves for all Rydberg states. The population curves obtained correlate with beam-foil experimental data concerning the S VI, Cl VII, and Ar VIII ions

  10. Autoionizing np Rydberg states of H2

    International Nuclear Information System (INIS)

    Xu, E.Y.; Helm, H.; Kachru, R.

    1989-01-01

    We report a study of the autoionizing np Rydberg states near the lowest ionization threshold of H 2 . Using resonant two-photon excitation, intermediate states in specific rotovibrational levels in the double well, E,F 1 Σ/sub g/ + states are prepared. Then, a second, tunable laser is used to photoionize via excitation of the np Rydberg states. Because of the stepwise laser excitation scheme employed in our experiment the photoionization occurs from states with vibrational wave functions very similar to those of the H 2 + core. As a consequence, the autoionizing states appear as nearly symmetric resonances, rather than the highly asymmetric Beutler-Fano profiles observed from the direct photoexcitation from the ground state of H 2 . Our experiments show that the J = 1 np states are broader than the J = 3 np states converging to the same limit, suggesting that the two states autoionize into the epsilon-cp and epsilon-cf continuum, respectively. We compare our observations with a theoretical analysis using a multichannel quantum defect theory. The J = 1 states reveal the profound effect caused by the perturbation of the autoionizing Rydberg series converging to the lowest vibrational and rotational state of H 2 + by low-n states converging to higher vibrational states of the H 2 -ion core

  11. Trojan wavepackets in helium - by core-Rydberg interaction

    International Nuclear Information System (INIS)

    Kalinski, M.; Eberly, J.H.

    1996-01-01

    The authors exhibit the existence of core-induced shape invariant wave packets in helium analogous to the Trojan wave packets predicted for hydrogen. They show that the core dipole moment oscillating with the Rabi frequency in the presence of a laser field will cause both radical and angular confinement of an outer Rydberg electron moving around a nearly circular orbit if the parameters of the orbit are properly chosen. They find the relation between the Rabi frequency of the core electron oscillations, laser field strength and the parameters of the Rydberg orbit of the outer electron

  12. GHz Rabi Flopping to Rydberg States in Hot Atomic Vapor Cells

    International Nuclear Information System (INIS)

    Huber, B.; Baluktsian, T.; Schlagmueller, M.; Koelle, A.; Kuebler, H.; Loew, R.; Pfau, T.

    2011-01-01

    We report on the observation of Rabi oscillations to a Rydberg state on a time scale below 1 ns in thermal rubidium vapor. We use a bandwidth-limited pulsed excitation and observe up to 6 full Rabi cycles within a pulse duration of ∼4 ns. We find good agreement between the experiment and numerical simulations based on a surprisingly simple model. This result shows that fully coherent dynamics with Rydberg states can be achieved even in thermal atomic vapor, thus suggesting small vapor cells as a platform for room-temperature quantum devices. Furthermore, the result implies that previous coherent dynamics in single-atom Rydberg gates can be accelerated by 3 orders of magnitude.

  13. Newton's Cradle and Entanglement Transport in a Flexible Rydberg Chain

    International Nuclear Information System (INIS)

    Wuester, S.; Ates, C.; Eisfeld, A.; Rost, J. M.

    2010-01-01

    In a regular, flexible chain of Rydberg atoms, a single electronic excitation localizes on two atoms that are in closer mutual proximity than all others. We show how the interplay between excitonic and atomic motion causes electronic excitation and diatomic proximity to propagate through the Rydberg chain as a combined pulse. In this manner entanglement is transferred adiabatically along the chain, reminiscent of momentum transfer in Newton's cradle.

  14. Wavepacket dynamics of a Rydberg atom monitored by a pair of time-delayed laser pulses

    Science.gov (United States)

    Xin, PeiPei; Cheng, Hong; Zhang, ShanShan; Wang, HanMu; Liu, HongPing

    2018-02-01

    We have investigated the Rydberg state population of an argon atom by an intense laser pulse and its wavepacket dynamics monitored by another successive laser pulse in the tunneling regime. A wavepacket comprising a superposition of close high-lying Rydberg states is irradiated by a multicycle laser pulse, where the sub-wave components in the wavepacket have fixed relative phases. A time-delayed second laser pulse is employed to apply on the excited Rydberg atom. If the time is properly chosen, one of the sub-wave components will be guided towards the ionization area while the rest remains intact. By means of this pump-probe technique, we could control and monitor the Rydberg wavepacket dynamics and reveal some interesting phenomenon such as the survival rate of individual Rydberg states related to the classical orbital period of electron.

  15. Multibit CkNOT quantum gates via Rydberg blockade

    DEFF Research Database (Denmark)

    Isenhower, L.; Saffman, Mark; Mølmer, Klaus

    2011-01-01

    Long range Rydberg blockade interactions have the potential for efficient implementation of quantum gates between multiple atoms. Here we present and analyze a protocol for implementation of a k-atom controlled NOT (CkNOT) neutral atom gate. This gate can be implemented using sequential or simult......Long range Rydberg blockade interactions have the potential for efficient implementation of quantum gates between multiple atoms. Here we present and analyze a protocol for implementation of a k-atom controlled NOT (CkNOT) neutral atom gate. This gate can be implemented using sequential...... or simultaneous addressing of the control atoms which requires only 2k + 3 or 5 Rydberg π pulses respectively. A detailed error analysis relevant for implementations based on alkali atom Rydberg states is provided which shows that gate errors less than 10% are possible for k = 35....

  16. Formation of Rydberg states in fast ion-atom collisions

    International Nuclear Information System (INIS)

    Schneider, D.; Kanter, E.P.; Vager, Z.; Gemmell, D.; Koch, P.; Mariani, D.; Van de Water, W.

    1983-01-01

    Previous results from beam-foil spectroscopy and from experiments using field ionization techniques have shown that a significant fraction of fast ionic projectiles traversing solid targets can be excited to high Rydberg states. We report an experimental investigation of Rydberg states formed in atomic and molecular ion beams (MeV) emerging from thin-carbon foils. Different field arrangements, including μ-wave fields, have been applied to study the effects of field ionization. The yields of electrons produced via field ionization are compared for different projectile atoms and molecules

  17. Charge-state-distributions of foil-excited heavy Rydberg atoms

    International Nuclear Information System (INIS)

    Faibis, A.; Kanter, E.P.; Koenig, W.; Zabransky, B.J.

    1985-01-01

    Studies of foil-excited fast (MeV/amu) heavy ions have demonstrated large yields of high Rydberg atoms formed in such beams. Further experiments have suggested a strong target-thickness dependence of the yields of such atoms. These results have been puzzling in view of the supposed short mean free paths of such atoms in solids. In an effort to better understand these results, the authors have measured the yields of Rydberg atoms (napprox.100-200) in foil-excited 32 S ions at an incident energy of 125 MeV

  18. Autoionizing process of double rydberg states in atom

    International Nuclear Information System (INIS)

    Xu, X. Y.; Huang, W.; Xu, C. B.; Xue, P.; Chen, D. Y.

    1997-01-01

    We have studied the autoionization distribution of penetrating double Rydberg (DR) states NLnl(N< n;L,l<4) experimentally in calcium by using five-laser resonance excitation and sequential ionization with a pulsed and a strong constant electric field, as well as theoretically in helium by using the hyperspherical close-coupling method. We have found the DR states autoionize with the ejected electron having its average kinetic energy nearly independent of n but apparently related to the binding energy of the ionic Rydberg orbit NL. We have also discussed the dynamics in DR states and described two types of autoionizing processes, i.e., 'penetration autoionization' and 'polarization autoionization' in DR states

  19. Spin-interaction effects for ultralong-range Rydberg molecules in a magnetic field

    Science.gov (United States)

    Hummel, Frederic; Fey, Christian; Schmelcher, Peter

    2018-04-01

    We investigate the fine and spin structure of ultralong-range Rydberg molecules exposed to a homogeneous magnetic field. Each molecule consists of a 87Rb Rydberg atom the outer electron of which interacts via spin-dependent s - and p -wave scattering with a polarizable 87Rb ground-state atom. Our model includes also the hyperfine structure of the ground-state atom as well as spin-orbit couplings of the Rydberg and ground-state atom. We focus on d -Rydberg states and principal quantum numbers n in the vicinity of 40. The electronic structure and vibrational states are determined in the framework of the Born-Oppenheimer approximation for varying field strengths ranging from a few up to hundred Gauss. The results show that the interplay between the scattering interactions and the spin couplings gives rise to a large variety of molecular states in different spin configurations as well as in different spatial arrangements that can be tuned by the magnetic field. This includes relatively regularly shaped energy surfaces in a regime where the Zeeman splitting is large compared to the scattering interaction but small compared to the Rydberg fine structure, as well as more complex structures for both weaker and stronger fields. We quantify the impact of spin couplings by comparing the extended theory to a spin-independent model.

  20. Rabi Oscillations between Ground and Rydberg States with Dipole-Dipole Atomic Interactions

    International Nuclear Information System (INIS)

    Johnson, T. A.; Urban, E.; Henage, T.; Isenhower, L.; Yavuz, D. D.; Walker, T. G.; Saffman, M.

    2008-01-01

    We demonstrate Rabi oscillations of small numbers of 87 Rb atoms between ground and Rydberg states with n≤43. Coherent population oscillations are observed for single atoms, while the presence of two or more atoms decoheres the oscillations. We show that these observations are consistent with van der Waals interactions of Rydberg atoms

  1. Evidence of circular Rydberg states in beam-foil experiments: Role of the surface wake field

    Science.gov (United States)

    Sharma, Gaurav; Puri, Nitin K.; Kumar, Pravin; Nandi, T.

    2017-12-01

    We have employed the concept of the surface wake field to model the formation of the circular Rydberg states in the beam-foil experiments. The experimental studies of atomic excitation processes show the formation of circular Rydberg states either in the bulk of the foil or at the exit surface, and the mechanism is explained by several controversial theories. The present model is based on the interesting fact that the charge state fraction as well as the surface wake field depend on the foil thickness and it resolves a long-standing discrepancy on the mechanism of the formation of circular Rydberg states. The influence of exit layers is twofold. Initially, the high angular momentum Rydberg states are produced in the last layers of the foil by the Stark switching due to the bulk wake field and finally, they are transferred to the circular Rydberg states as a single multiphoton process due to the influence of the surface wake field.

  2. Photoionization of Rydberg hydrogen atom in a magnetic field

    International Nuclear Information System (INIS)

    Wang, Dehua; Cheng, Shaohao; Chen, Zhaohang

    2015-01-01

    Highlights: • The ionization of Rydberg hydrogen atom in a magnetic field has been studied. • Oscillatory structures appear in the electron probability density distributions. • This study can guide the experimental research on the photoionization microscopy. - Abstract: The ionization of Rydberg hydrogen atom in a magnetic field has been studied on the basis of a semiclassical analysis of photoionization microscopy. The photoionization microscopy interference patterns of the photoelectron probability density distribution on a given detector plane are calculated at different scaled energies. We find that due to the interference effect of different types of electron trajectories arrived at a given point on the detector plane, oscillatory structures appear in the electron probability density distributions. The oscillatory structure of the interference pattern, which contains the spatial component of the electronic wave function, evolves sensitively on the scaled energy, through which we gain a deep understanding on the probability density distribution of the electron wave function. This study provides some reference values for the future experiment research on the photoionization microscopy of the Rydberg atom in the presence of magnetic field

  3. Rydberg phases of Hydrogen and low energy nuclear reactions

    Science.gov (United States)

    Olafsson, Sveinn; Holmlid, Leif

    2016-03-01

    For over the last 26 years the science of cold fusion/LENR has been researched around the world with slow pace of progress. Modest quantity of excess heat and signatures of nuclear transmutation and helium production have been confirmed in experiments and theoretical work has only resulted in a large flora of inadequate theoretical scenarios. Here we review current state of research in Rydberg matter of Hydrogen that is showing strong signature of nuclear processes. In the presentation experimental behavior of Rydberg matter of hydrogen is described. An extensive collaboration effort of surface physics, catalysis, atomic physics, solid state physics, nuclear physics and quantum information is need to tackle the surprising experimental results that have so far been obtained. Rydberg matter of Hydrogen is the only known state of matter that is able to bring huge collection of protons to so short distances and for so long time that tunneling becomes a reasonable process for making low energy nuclear reactions. Nuclear quantum entanglement can also become realistic process at theses conditions.

  4. Quantum localization in the three-dimensional kicked Rydberg atom

    International Nuclear Information System (INIS)

    Persson, Emil; Yoshida, Shuhei; Burgdoerfer, Joachim; Tong, X.-M.; Reinhold, Carlos O.

    2003-01-01

    We study the three-dimensional (3D) unidirectionally kicked Rydberg atom. For parabolic initial states elongated in the direction of the kicks we show that the ionization of the quantum system is suppressed as compared to the classical counterpart and that the quantum wave function is localized along all degrees of freedom, whereas the classical system is globally diffusive. We discuss the connection to the previously studied one-dimensional (1D) model of the kicked Rydberg atom and verify that the 1D model is a good approximation to the 3D quantum case in the limiting case of the most elongated initial states. We further study the quantum phase-space distribution (Husimi distribution) of the eigenstates of the period-one time-evolution (Floquet) operator and show that the eigenstates are localized in phase space. For the most elongated parabolic initial state, we are able to identify the unstable periodic orbits around which Floquet states localize. We discuss the possibility of observing quantum localization in high Rydberg states in n>100

  5. Single-photon cesium Rydberg excitation spectroscopy using 318.6-nm UV laser and room-temperature vapor cell.

    Science.gov (United States)

    Wang, Jieying; Bai, Jiandong; He, Jun; Wang, Junmin

    2017-09-18

    We demonstrate a single-photon Rydberg excitation spectroscopy of cesium (Cs) atoms in a room-temperature vapor cell. Cs atoms are excited directly from 6S 1/2 ground state to nP 3/2 (n = 70 - 100) Rydberg states with a 318.6 nm ultraviolet (UV) laser, and Rydberg excitation spectra are obtained by transmission enhancement of a probe beam resonant to Cs 6S 1/2 , F = 4 - 6P 3/2 , F' = 5 transition as partial population on F = 4 ground state are transferred to Rydberg state. Analysis reveals that the observed spectra are velocity-selective spectroscopy of Rydberg state, from which the amplitude and linewidth influenced by lasers' Rabi frequency have been investigated. Fitting to energies of Cs nP 3/2 (n = 70 -100) states, the determined quantum defect is 3.56671(42). The demodulated spectra can also be employed as frequency references to stabilize the UV laser frequency to specific Cs Rydberg transition.

  6. Dissipation-induced dipole blockade and antiblockade in driven Rydberg systems

    Science.gov (United States)

    Young, Jeremy T.; Boulier, Thomas; Magnan, Eric; Goldschmidt, Elizabeth A.; Wilson, Ryan M.; Rolston, Steven L.; Porto, James V.; Gorshkov, Alexey V.

    2018-02-01

    We study theoretically and experimentally the competing blockade and antiblockade effects induced by spontaneously generated contaminant Rydberg atoms in driven Rydberg systems. These contaminant atoms provide a source of strong dipole-dipole interactions and play a crucial role in the system's behavior. We study this problem theoretically using two different approaches. The first is a cumulant expansion approximation, in which we ignore third-order and higher connected correlations. Using this approach for the case of resonant drive, a many-body blockade radius picture arises, and we find qualitative agreement with previous experimental results. We further predict that as the atomic density is increased, the Rydberg population's dependence on Rabi frequency will transition from quadratic to linear dependence at lower Rabi frequencies. We study this behavior experimentally by observing this crossover at two different atomic densities. We confirm that the larger density system has a smaller crossover Rabi frequency than the smaller density system. The second theoretical approach is a set of phenomenological inhomogeneous rate equations. We compare the results of our rate-equation model to the experimental observations [E. A. Goldschmidt et al., Phys. Rev. Lett. 116, 113001 (2016), 10.1103/PhysRevLett.116.113001] and find that these rate equations provide quantitatively good scaling behavior of the steady-state Rydberg population for both resonant and off-resonant drives.

  7. Observation of the Borromean Three-Body Förster Resonances for Three Interacting Rb Rydberg Atoms.

    Science.gov (United States)

    Tretyakov, D B; Beterov, I I; Yakshina, E A; Entin, V M; Ryabtsev, I I; Cheinet, P; Pillet, P

    2017-10-27

    Three-body Förster resonances at long-range interactions of Rydberg atoms were first predicted and observed in Cs Rydberg atoms by Faoro et al. [Nat. Commun. 6, 8173 (2015)NCAOBW2041-172310.1038/ncomms9173]. In these resonances, one of the atoms carries away an energy excess preventing the two-body resonance, leading thus to a Borromean type of Förster energy transfer. But they were in fact observed as the average signal for the large number of atoms N≫1. In this Letter, we report on the first experimental observation of the three-body Förster resonances 3×nP_{3/2}(|M|)→nS_{1/2}+(n+1)S_{1/2}+nP_{3/2}(|M^{*}|) in a few Rb Rydberg atoms with n=36, 37. We have found here clear evidence that there is no signature of the three-body Förster resonance for exactly two interacting Rydberg atoms, while it is present for N=3-5 atoms. This demonstrates the assumption that three-body resonances can generalize to any Rydberg atom. As such resonance represents an effective three-body operator, it can be used to directly control the three-body interactions in quantum simulations and quantum information processing with Rydberg atoms.

  8. Anisotropic Interactions between Cold Rydberg Atoms

    Science.gov (United States)

    2015-09-28

    AFRL-AFOSR-CL-TR-2015-0002 Anisotropic interactions between cold Rydberg atoms Luis Marcassa INSTITUTO DE FISICA DE SAO CARLOS Final Report 09/28...problem with the report +551633739806 Organization / Institution name Instituto de Fisica de Sao Carlos Grant/Contract Title The full title of the

  9. Proposal for the determination of nuclear masses by high-precision spectroscopy of Rydberg states

    International Nuclear Information System (INIS)

    Wundt, B J; Jentschura, U D

    2010-01-01

    The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to the nuclear mass. As a consequence, spectroscopic measurements of Rydberg transitions can be used in order to precisely deduce nuclear masses. A possible application of this approach to hydrogen and deuterium, and hydrogen-like lithium and carbon is explored in detail. In order to complete the analysis, numerical and analytic calculations of the quantum electrodynamic self-energy remainder function for states with principal quantum number n = 5, ..., 8 and with angular momentum l = n - 1 and l = n - 2 are described (j = l +- 1/2).

  10. Proposal for the determination of nuclear masses by high-precision spectroscopy of Rydberg states

    Energy Technology Data Exchange (ETDEWEB)

    Wundt, B J; Jentschura, U D [Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409-0640 (United States)

    2010-06-14

    The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to the nuclear mass. As a consequence, spectroscopic measurements of Rydberg transitions can be used in order to precisely deduce nuclear masses. A possible application of this approach to hydrogen and deuterium, and hydrogen-like lithium and carbon is explored in detail. In order to complete the analysis, numerical and analytic calculations of the quantum electrodynamic self-energy remainder function for states with principal quantum number n = 5, ..., 8 and with angular momentum l = n - 1 and l = n - 2 are described (j = l {+-} 1/2).

  11. Interaction of K(nd) Rydberg atoms with an amorphous gold surface

    International Nuclear Information System (INIS)

    Gray, D.F.

    1988-01-01

    This thesis reports the first controlled study of the interactions of Rydberg atoms with a metal surface. In these experiments, a collimated beam of potassium Rydberg atoms is directed at a plane surface at near grazing incidence. Positive ions formed by surface ionization are attracted to the surface by their image charge, which is counterbalanced by an external electric field applied perpendicular to the surface. The ions are detected by a position-sensitive detector (PSD). At some critical value of the external field, the ion trajectories just miss the surface, suggesting that analysis of the dependence of the ion signals of external electric field can be used to determine the distance from the surface at which ionization occurs. This distance, and thus the corresponding critical electric field, is expected to be n-dependent. Experimentally, however, it was observed that the ion signal had a sudden n-independent onset when only a small positive perpendicular electric field was applied at the surface. This observation requires, surprisingly, that the ions produced by surface ionization can readily escape from the surface. The data do, however, show that Rydberg atoms are efficiently ionized in collisions with the surface. This process may provide a useful new detection technique for Rydberg atoms

  12. Rydberg excitation of neutral nitric oxide molecules in strong UV and near-IR laser fields

    International Nuclear Information System (INIS)

    Lv Hang; Zhang Jun-Feng; Zuo Wan-Long; Xu Hai-Feng; Jin Ming-Xing; Ding Da-Jun

    2015-01-01

    Rydberg state excitations of neutral nitric oxide molecules are studied in strong ultraviolet (UV) and near-infra-red (IR) laser fields using a linear time-of-flight (TOF) mass spectrometer with the pulsed electronic field ionization method. The yield of Rydberg molecules is measured as a function of laser intensity and ellipticity, and the results in UV laser fields are compared with those in near-IR laser fields. The present study provides the first experimental evidence of neutral Rydberg molecules surviving in a strong laser field. The results indicate that a rescattering-after-tunneling process is the main contribution to the formation of Rydberg molecules in strong near-IR laser fields, while multi-photon excitation may play an important role in the strong UV laser fields. (paper)

  13. Optical Measurements of Strong Radio-Frequency Fields Using Rydberg Atoms

    Science.gov (United States)

    Miller, Stephanie Anne

    There has recently been an initiative toward establishing atomic measurement standards for field quantities, including radio-frequency, millimeter-wave, and micro-wave electric fields. Current measurement standards are obtained using dipole antennas, which are fundamentally limited in frequency bandwidth (set by the physical size of the antenna) and accuracy (due to the metal perturbing the field during the measurement). Establishing an atomic standard rectifies these problems. My thesis work contributes to an ongoing effort towards establishing the viability of using Rydberg electromagnetically induced transparency (EIT) to perform atom-based measurements of radio-frequency (RF) fields over a wide range of frequencies and field strengths, focusing on strong-field measurements. Rydberg atoms are atoms with an electron excited to a high principal quantum number, resulting in a high sensitivity to an applied field. A model based on Floquet theory is implemented to accurately describe the observed atomic energy level shifts from which information about the field is extracted. Additionally, the effects due to the different electric field domains within the measurement volume are accurately modeled. Absolute atomic measurements of fields up to 296 V/m within a +/-0.35% relative uncertainty are demonstrated. This is the strongest field measured at the time of data publication. Moreover, the uncertainty is over an order of magnitude better than that of current standards. A vacuum chamber setup that I implemented during my graduate studies is presented and its unique components are detailed. In this chamber, cold-atom samples are generated and Rydberg atoms are optically excited within the ground-state sample. The Rydberg ion detection and imaging procedure are discussed, particularly the high magnification that the system provides. By analyzing the position of the ions, the spatial correlation g(2) (r) of Rydberg-atom distributions can be extracted. Aside from ion

  14. Application of the Faddeev-Watson expansion to thermal collisions of Rydberg atoms with neutral particles

    International Nuclear Information System (INIS)

    de Prunele, E.

    1983-01-01

    The Faddeev-Watson expansion (FWE) for the T operator is applied to the study of thermal collisions between Rydberg atom and neutral atom. These collisions are considered as a three-body problem (the perturber, the Rydberg electron, and its parent core) and it is assumed, as already done in most theoretical works dealing with Rydberg-atom--atom collisions, that the core-perturber interaction can be neglected. Then the evaluation of the FWE first- and second-order terms is made tractable by using an appropriate separable potential for the Rydberg-electron--perturber interaction. The evaluation of the second-order term allows us to estimate the importance of taking into account explicitly the Rydberg-electron--core interaction in the expression of the (three-body) T operator for the thermal collisions considered. Detailed calculations for the process Rb(n, l = 0)+He →Rb(n',l')+He are presented and discussed. The FWE second-order term has been evaluated for the first time by taking the (two-body) t operator associated with the Rydberg atom (valence electron plus parent core) as the Coulomb potential. The contribution of the FWE second-order term to the scattering amplitude decreases as n increases and is found especially significant when both the momentum transfers involved in the collision are large and the values of l and l' are small

  15. Rydberg states of chloroform studied by VUV photoabsorption spectroscopy

    International Nuclear Information System (INIS)

    Singh, Param Jeet; Shastri, Aparna; D’Souza, R.; Jagatap, B.N.

    2013-01-01

    The VUV photoabsorption spectra of CHCl 3 and CDCl 3 in the energy region 6.2–11.8 eV (50,000–95,000 cm −1 ) have been investigated using synchrotron radiation from the Indus-1 source. Rydberg series converging to the first four ionization limits at 11.48, 11.91, 12.01 and 12.85 eV corresponding to excitation from the 1a 2 , 4a 1 , 4e, 3e, orbitals of CHCl 3 respectively are identified and analyzed. Quantum defect values are observed to be consistent with excitation from the chlorine lone pair orbitals. Vibrational progressions observed in the region of 72,500–76,500 cm −1 have been reassigned to ν 3 and combination modes of ν 3 +ν 6 belonging to the 1a 2 →4p transition in contrast to earlier studies where they were assigned to a ν 3 progression superimposed on the 3e→4p Rydberg transition. The assignments are further confirmed based on isotopic substitution studies on CDCl 3 whose VUV photoabsorption spectrum is reported here for the first time. The frequencies of the ν 3 and ν 6 modes in the 4p Rydberg state of CHCl 3 (CDCl 3 ) are proposed to be ∼454 (409) cm −1 and∼130 (129) cm −1 respectively based on the vibronic analysis. DFT calculations of neutral and ionic ground state vibrational frequencies support the vibronic analysis. Experimental spectrum is found to be in good agreement with that predicted by TDDFT calculations. This work presents a consolidated analysis of the VUV photoabsorption spectrum of chloroform. -- Highlights: •VUV photoabsorption spectra of CHCl 3 and CDCl 3 studied using synchrotron radiation. •Quantum defect analysis of Rydberg series converging to first four ionization limits. •Vibronic bands in 72,500–76,500 cm −1 region assigned to 1a 2 →4p Rydberg transition. •Vibrational progressions assigned to ν 3 and ν 3 +ν 6 using ab initio calculations. •Excellent agreement of TDDFT vertical excited energies with experimental spectrum

  16. Analysis of imperfections in the coherent optical excitation of single atoms to Rydberg states

    Science.gov (United States)

    de Léséleuc, Sylvain; Barredo, Daniel; Lienhard, Vincent; Browaeys, Antoine; Lahaye, Thierry

    2018-05-01

    We study experimentally various physical limitations and technical imperfections that lead to damping and finite contrast of optically driven Rabi oscillations between ground and Rydberg states of a single atom. Finite contrast is due to preparation and detection errors, and we show how to model and measure them accurately. Part of these errors originates from the finite lifetime of Rydberg states, and we observe its n3 scaling with the principal quantum number n . To explain the damping of Rabi oscillations, we use simple numerical models taking into account independently measured experimental imperfections and show that the observed damping actually results from the accumulation of several small effects, each at the level of a few percent. We discuss prospects for improving the coherence of ground-Rydberg Rabi oscillations in view of applications in quantum simulation and quantum information processing with arrays of single Rydberg atoms.

  17. Wave packet fractional revivals in a one-dimensional Rydberg atom

    International Nuclear Information System (INIS)

    Veilande, Rita; Bersons, Imants

    2007-01-01

    We investigate many characteristic features of revival and fractional revival phenomena via derived analytic expressions for an autocorrelation function of a one-dimensional Rydberg atom with weighting probabilities modelled by a Gaussian or a Lorentzian distribution. The fractional revival phenomenon in the ionization probabilities of a one-dimensional Rydberg atom irradiated by two short half-cycle pulses is also studied. When many states are involved in the formation of the wave packet, the revival is lower and broader than the initial wave packet and the fractional revivals overlap and disappear with time

  18. Quantum simulation of transverse Ising models with Rydberg atoms

    Science.gov (United States)

    Schauss, Peter

    2018-04-01

    Quantum Ising models are canonical models for the study of quantum phase transitions (Sachdev 1999 Quantum Phase Transitions (Cambridge: Cambridge University Press)) and are the underlying concept for many analogue quantum computing and quantum annealing ideas (Tanaka et al Quantum Spin Glasses, Annealing and Computation (Cambridge: Cambridge University Press)). Here we focus on the implementation of finite-range interacting Ising spin models, which are barely tractable numerically. Recent experiments with cold atoms have reached the interaction-dominated regime in quantum Ising magnets via optical coupling of trapped neutral atoms to Rydberg states. This approach allows for the tunability of all relevant terms in an Ising spin Hamiltonian with 1/{r}6 interactions in transverse and longitudinal fields. This review summarizes the recent progress of these implementations in Rydberg lattices with site-resolved detection. Strong correlations in quantum Ising models have been observed in several experiments, starting from a single excitation in the superatom regime up to the point of crystallization. The rapid progress in this field makes spin systems based on Rydberg atoms a promising platform for quantum simulation because of the unmatched flexibility and strength of interactions combined with high control and good isolation from the environment.

  19. Many-body dynamics of driven-dissipative Rydberg cavity polaritons

    Science.gov (United States)

    Pistorius, Tim; Fan, Jingtao; Weimer, Hendrik

    2017-04-01

    The usage of photons as long-range information carriers has greatly increased the interest in systems with nonlinear optical properties in recent years. The nonlinearity is easily achievable in Rydberg mediums through the strong van der Waals interaction which makes them one of the best candidates for such a system. Here, we propose a way to analyze the steady state solutions of a Rydberg medium in a cavity through the combination of the variational principle for open quantum systems and the P-distribution of the density matrix. To get a better understanding of the many-body-dynamics a transformation into the polariton picture is performed and investigated. Volkswagen Foundation, Deutsche Forschungsgemeinschaft.

  20. Rydberg Molecules for Ion-Atom Scattering in the Ultracold Regime.

    Science.gov (United States)

    Schmid, T; Veit, C; Zuber, N; Löw, R; Pfau, T; Tarana, M; Tomza, M

    2018-04-13

    We propose a novel experimental method to extend the investigation of ion-atom collisions from the so far studied cold, essentially classical regime to the ultracold, quantum regime. The key aspect of this method is the use of Rydberg molecules to initialize the ultracold ion-atom scattering event. We exemplify the proposed method with the lithium ion-atom system, for which we present simulations of how the initial Rydberg molecule wave function, freed by photoionization, evolves in the presence of the ion-atom scattering potential. We predict bounds for the ion-atom scattering length from ab initio calculations of the interaction potential. We demonstrate that, in the predicted bounds, the scattering length can be experimentally determined from the velocity of the scattered wave packet in the case of ^{6}Li^{+}-^{6}Li and from the molecular ion fraction in the case of ^{7}Li^{+}-^{7}Li. The proposed method to utilize Rydberg molecules for ultracold ion-atom scattering, here particularized for the lithium ion-atom system, is readily applicable to other ion-atom systems as well.

  1. Fundamental constants and tests of theory in Rydberg states of hydrogenlike ions.

    Science.gov (United States)

    Jentschura, Ulrich D; Mohr, Peter J; Tan, Joseph N; Wundt, Benedikt J

    2008-04-25

    A comparison of precision frequency measurements to quantum electrodynamics (QED) predictions for Rydberg states of hydrogenlike ions can yield information on values of fundamental constants and test theory. With the results of a calculation of a key QED contribution reported here, the uncertainty in the theory of the energy levels is reduced to a level where such a comparison can yield an improved value of the Rydberg constant.

  2. Fundamental Constants and Tests of Theory in Rydberg States of Hydrogenlike Ions

    International Nuclear Information System (INIS)

    Jentschura, Ulrich D.; Mohr, Peter J.; Tan, Joseph N.; Wundt, Benedikt J.

    2008-01-01

    A comparison of precision frequency measurements to quantum electrodynamics (QED) predictions for Rydberg states of hydrogenlike ions can yield information on values of fundamental constants and test theory. With the results of a calculation of a key QED contribution reported here, the uncertainty in the theory of the energy levels is reduced to a level where such a comparison can yield an improved value of the Rydberg constant

  3. Entropy and complexity analysis of hydrogenic Rydberg atoms

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Rosa, S. [Instituto Carlos I de Fisica Teorica y Computacional, Universidad de Granada, 18071-Granada (Spain); Departamento de Fisica Aplicada II, Universidad de Sevilla, 41012-Sevilla (Spain); Toranzo, I. V.; Dehesa, J. S. [Instituto Carlos I de Fisica Teorica y Computacional, Universidad de Granada, 18071-Granada (Spain); Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, 18071-Granada (Spain); Sanchez-Moreno, P. [Instituto Carlos I de Fisica Teorica y Computacional, Universidad de Granada, 18071-Granada (Spain); Departamento de Matematica Aplicada, Universidad de Granada, 18071-Granada (Spain)

    2013-05-15

    The internal disorder of hydrogenic Rydberg atoms as contained in their position and momentum probability densities is examined by means of the following information-theoretic spreading quantities: the radial and logarithmic expectation values, the Shannon entropy, and the Fisher information. As well, the complexity measures of Cramer-Rao, Fisher-Shannon, and Lopez Ruiz-Mancini-Calvet types are investigated in both reciprocal spaces. The leading term of these quantities is rigorously calculated by use of the asymptotic properties of the concomitant entropic functionals of the Laguerre and Gegenbauer orthogonal polynomials which control the wavefunctions of the Rydberg states in both position and momentum spaces. The associated generalized Heisenberg-like, logarithmic and entropic uncertainty relations are also given. Finally, application to linear (l= 0), circular (l=n- 1), and quasicircular (l=n- 2) states is explicitly done.

  4. Molecular ions, Rydberg spectroscopy and dynamics

    International Nuclear Information System (INIS)

    Jungen, Ch.

    2015-01-01

    Ion spectroscopy, Rydberg spectroscopy and molecular dynamics are closely related subjects. Multichannel quantum defect theory is a theoretical approach which draws on this close relationship and thereby becomes a powerful tool for the study of systems consisting of a positively charged molecular ion core interacting with an electron which may be loosely bound or freely scattering

  5. Molecular ions, Rydberg spectroscopy and dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Jungen, Ch. [Laboratoire Aimé Cotton, Université de Paris-Sud, 91405 Orsay (France)

    2015-01-22

    Ion spectroscopy, Rydberg spectroscopy and molecular dynamics are closely related subjects. Multichannel quantum defect theory is a theoretical approach which draws on this close relationship and thereby becomes a powerful tool for the study of systems consisting of a positively charged molecular ion core interacting with an electron which may be loosely bound or freely scattering.

  6. Formation of Antihydrogen Rydberg atoms in strong magnetic field traps

    International Nuclear Information System (INIS)

    Pohl, T.; Sadeghpour, H. R.

    2008-01-01

    It is shown that several features of antihydrogen production in nested Penning traps can be described with accurate and efficient Monte Carlo simulations. It is found that cold deeply-bound Rydberg states of antihydrogen (H-bar) are produced in three-body capture in the ATRAP experiments and an additional formation mechanism -Rydberg charge transfer-, particular to the nested Penning trap geometry, is responsible for the observed fast (hot) H-bar atoms. Detailed description of the numerical propagation technique for following extreme close encounters is given. An analytic derivation of the power law behavior of the field ionization spectrum is provided

  7. Nuclear spin transitions in the kHz range in Rydberg matter clusters give precise values of the internal magnetic field from orbiting Rydberg electrons

    International Nuclear Information System (INIS)

    Holmlid, Leif

    2009-01-01

    Clusters of the electronically excited condensed matter Rydberg matter (RM) are planar and sixfold symmetric with specific magic numbers N as shown by rotational spectroscopy of potassium K N clusters [L. Holmlid, Mol. Phys. 105 (2007) 933; L. Holmlid, J. Mol. Struct. 885 (2008) 122]. In radio frequency emission spectra from such clusters, features are observed that are due to the hyperfine interaction between the atomic nucleus 39 K and two Rydberg electrons. These electrons exist in a doubly excited K atom at n'' = 5 or 6 in a 'sleeping-top' type rotating cluster. Such low excited electrons were observed recently in optical intra-cavity experiments in K(RM), where the electrons in the conduction band are involved in the angular momentum conservation in the stimulated emission. Here we show that the agreement with the theoretical description of circular Rydberg states is excellent within ±0.2% in the magnetic field, invoking angular momentum conservation by electrons in the condensed phase. Sleeping-top clusters may form stacks of clusters, and it is likely that such stacks are the emitting entities involved in the two nuclear spin series observed.

  8. Heavy Rydberg behaviour in high vibrational levels of some ion-pair states of the halogens and inter-halogens

    International Nuclear Information System (INIS)

    Donovan, Robert J.; Lawley, Kenneth P.; Ridley, Trevor

    2015-01-01

    We report the identification of heavy Rydberg resonances in the ion-pair spectra of I 2 , Cl 2 , ICl, and IBr. Extensive vibrational progressions are analysed in terms of the energy dependence of the quantum defect δ(E b ) rather than as Dunham expansions. This is shown to define the heavy Rydberg region, providing a more revealing fit to the data with fewer coefficients and leads just as easily to numbering data sets separated by gaps in the observed vibrational progressions. Interaction of heavy Rydberg states with electronic Rydberg states at avoided crossings on the inner wall of the ion-pair potential is shown to produce distinctive changes in the energy dependence of δ(E b ), with weak and strong interactions readily distinguished. Heavy Rydberg behaviour is found to extend well below near-dissociation states, down to vibrational levels ∼18 000-20 000 cm −1 below dissociation. The rapid semi-classical calculation of δ(E b ) for heavy Rydberg states is emphasised and shows their absolute magnitude to be essentially the volume of phase space excluded from the vibrational motion by avoiding core-core penetration of the ions

  9. Evaluation of Container Closure System Integrity for Frozen Storage Drug Products.

    Science.gov (United States)

    Nieto, Alejandra; Roehl, Holger; Brown, Helen; Nikoloff, Jonas; Adler, Michael; Mahler, Hanns-Christian

    2016-01-01

    Sometimes, drug product for parenteral administration is stored in a frozen state (e.g., -20 °C or -80 °C), particularly during early stages of development of some biotech molecules in order to provide sufficient stability. Shipment of frozen product could potentially be performed in the frozen state, yet possibly at different temperatures, for example, using dry ice (-80 °C). Container closure systems of drug products usually consist of a glass vial, rubber stopper, and an aluminum crimped cap. In the frozen state, the glass transition temperature (Tg) of commonly used rubber stoppers is between -55 and -65 °C. Below their Tg, rubber stoppers are known to lose their elastic properties and become brittle, and thus potentially fail to maintain container closure integrity in the frozen state. Leaks during frozen temperature storage and transportation are likely to be transient, yet, can possibly risk container closure integrity and lead to microbial contamination. After thawing, the rubber stopper is supposed to re-seal the container closure system. Given the transient nature of the possible impact on container closure integrity in the frozen state, typical container closure integrity testing methods (used at room temperature conditions) are unable to evaluate and thus confirm container closure integrity in the frozen state. Here we present the development of a novel method (thermal physical container closure integrity) for direct assessment of container closure integrity by a physical method (physical container closure integrity) at frozen conditions, using a modified He leakage test. In this study, different container closure systems were evaluated with regard to physical container closure integrity in the frozen state to assess the suitability of vial/stopper combinations and were compared to a gas headspace method. In summary, the thermal physical container closure integrity He leakage method was more sensitive in detecting physical container closure

  10. Effect of finite detection efficiency on the observation of the dipole-dipole interaction of a few Rydberg atoms

    International Nuclear Information System (INIS)

    Ryabtsev, I. I.; Tretyakov, D. B.; Beterov, I. I.; Entin, V. M.

    2007-01-01

    We have developed a simple analytical model describing multiatom signals that are measured in experiments on dipole-dipole interaction at resonant collisions of a few Rydberg atoms. It has been shown that finite efficiency of the selective field-ionization detector leads to the mixing up of the spectra of resonant collisions registered for various numbers of Rydberg atoms. The formulas which help to estimate an appropriate mean Rydberg atom number for a given detection efficiency are presented. We have found that a measurement of the relation between the amplitudes of collisional resonances observed in the one- and two-atom signals provides a straightforward determination of the absolute detection efficiency and mean Rydberg atom number. We also performed a testing experiment on resonant collisions in a small excitation volume of a sodium atomic beam. The resonances observed for 1-4 detected Rydberg atoms have been analyzed and compared with theory

  11. Entropy and complexity analysis of hydrogenic Rydberg atoms

    International Nuclear Information System (INIS)

    López-Rosa, S.; Toranzo, I. V.; Dehesa, J. S.; Sánchez-Moreno, P.

    2013-01-01

    The internal disorder of hydrogenic Rydberg atoms as contained in their position and momentum probability densities is examined by means of the following information-theoretic spreading quantities: the radial and logarithmic expectation values, the Shannon entropy, and the Fisher information. As well, the complexity measures of Crámer-Rao, Fisher-Shannon, and López Ruiz-Mancini-Calvet types are investigated in both reciprocal spaces. The leading term of these quantities is rigorously calculated by use of the asymptotic properties of the concomitant entropic functionals of the Laguerre and Gegenbauer orthogonal polynomials which control the wavefunctions of the Rydberg states in both position and momentum spaces. The associated generalized Heisenberg-like, logarithmic and entropic uncertainty relations are also given. Finally, application to linear (l= 0), circular (l=n− 1), and quasicircular (l=n− 2) states is explicitly done.

  12. Determination of first ionization potential of samarium atom using Rydberg series convergence

    International Nuclear Information System (INIS)

    Jayasekharan, T.; Razvi, M.A.N.; Bhale, G.L.

    1999-01-01

    The study of Rydberg states has recently received more attention partially because an efficient isotope selective ionization is possible via these states. In addition, their investigation provides useful information on the atomic structure. An electron in a shell with a high principal quantum number is a sensitive probe for the interaction with the ionic core of the atom. Measurements of these Rydberg levels give valuable data on quantum defects, anomalies in fine structure splitting, polarizabilities, configuration interactions, ionization potentials etc

  13. From the Rydberg constant to the fundamental constants metrology; De la constante de Rydberg a la metrologie des constantes fondamentales

    Energy Technology Data Exchange (ETDEWEB)

    Nez, F

    2005-06-15

    This document reviews the theoretical and experimental achievements of the author since the beginning of his scientific career. This document is dedicated to the spectroscopy of hydrogen, deuterium and helium atoms. The first part is divided into 6 sub-sections: 1) the principles of hydrogen spectroscopy, 2) the measurement of the 2S-nS/nD transitions, 3) other optical frequency measurements, 4) our contribution to the determination of the Rydberg constant, 5) our current experiment on the 1S-3S transition, 6) the spectroscopy of the muonic hydrogen. Our experiments have improved the accuracy of the Rydberg Constant by a factor 25 in 15 years and we have achieved the first absolute optical frequency measurement of a transition in hydrogen. The second part is dedicated to the measurement of the fine structure constant and the last part deals with helium spectroscopy and the search for optical references in the near infrared range. (A.C.)

  14. Observation and measurement of interaction-induced dispersive optical nonlinearities in an ensemble of cold rydberg atoms

    DEFF Research Database (Denmark)

    Parigi, V.; Bimbard, E.; Stanojevic, J.

    2012-01-01

    We observe and measure dispersive optical nonlinearities in an ensemble of cold Rydberg atoms placed inside an optical cavity. The experimental results are in agreement with a simple model where the optical nonlinearities are due to the progressive appearance of a Rydberg blockaded volume within...

  15. Investigation by high resolution electron spectroscopy of the helium-like 3lnl' Rydberg series in double capture processes at low collision velocity: auto transfer to Rydberg states and electron stabilization

    International Nuclear Information System (INIS)

    Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Gonzalez, A.; Benhenni, M.; Bachau, H.; Sanchez, I.

    1994-01-01

    A high resolution electron spectrometry of the (3lnl') Ryberg series populated in N 7+ + He and Ne 10+ + He collisions at 10 q keV, 10 o allows us to observe, for the first time by this method, two post-collisional effects. First, it is found with nitrogen ions that, when n increases from n = 4 to 9, the L-distribution peaks more and more on the high angular momentum states. This is qualitatively understood as a Stark deformation of the Rydberg orbit by the Coulomb field of the receding ion. Also, in the n range where the double capture process populates symmetrical 4l4l' states (n>9), an enhancement of the intensities of the 3lnl' Rydberg lines is observed for both collisonal systems. This is thought to be a signature of the so-called auto transfer to Rydberg states effect. The transfer of population from the 3l4l' to the 3lnl' states is found to be favoured against a direct autoionization of these 4l4l' states into the n = 2 continuum. These experimental findings together with preliminary spectroscopic calculations concerning the configuration interaction of the Ne 8+ (4l4l') states with the Ne 8+ (3lnl') Rydberg series are also discussed within the context of the electron stabilization which follows a double capture. (Author)

  16. Predissociation of high-lying Rydberg states of molecular iodine via ion-pair states

    Energy Technology Data Exchange (ETDEWEB)

    Bogomolov, Alexandr S. [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation); Grüner, Barbara; Mudrich, Marcel [Physikalisches Institut, Universität Freiburg, D-79104 Freiburg (Germany); Kochubei, Sergei A. [Institute of Semiconductor Physics, ac. Lavrent' yev ave., 13, Novosibirsk 630090 (Russian Federation); Baklanov, Alexey V. [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090 (Russian Federation)

    2014-03-28

    Velocity map imaging of the photofragments arising from two-photon photoexcitation of molecular iodine in the energy range 73 500–74 500 cm{sup −1} covering the bands of high-lying gerade Rydberg states [{sup 2}Π{sub 1/2}]{sub c}6d;0{sub g}{sup +} and [{sup 2}Π{sub 1/2}]{sub c}6d;2{sub g} has been applied. The ion signal was dominated by the atomic fragment ion I{sup +}. Up to 5 dissociation channels yielding I{sup +} ions with different kinetic energies were observed when the I{sub 2} molecule was excited within discrete peaks of Rydberg states and their satellites in this region. One of these channels gives rise to images of I{sup +} and I{sup −} ions with equal kinetic energy indicating predissociation of I{sub 2} via ion-pair states. The contribution of this channel was up to about 50% of the total I{sup +} signal. The four other channels correspond to predissociation via lower lying Rydberg states giving rise to excited iodine atoms providing I{sup +} ions by subsequent one-photon ionization by the same laser pulse. The ratio of these channels varied from peak to peak in the spectrum but their total ionic signal was always much higher than the signal of (2 + 1) resonance enhanced multi-photon ionization of I{sub 2}, which was previously considered to be the origin of ionic signal in this spectral range. The first-tier E0{sub g}{sup +} and D{sup ′}2{sub g} ion-pair states are concluded to be responsible for predissociation of Rydberg states [{sup 2}Π{sub 1/2}]{sub c}6d;0{sub g}{sup +} and [{sup 2}Π{sub 1/2}]{sub c}6d;2{sub g}, respectively. Further predissociation of these ion-pair states via lower lying Rydberg states gives rise to excited I(5s{sup 2}5p{sup 4}6s{sup 1}) atoms responsible for major part of ion signal. The isotropic angular distribution of the photofragment recoil directions observed for all channels indicates that the studied Rydberg states are long-lived compared with the rotational period of the I{sub 2} molecule.

  17. Hypervelocity Launching and Frozen Fuels as a Major Contribution to Spaceflight

    Science.gov (United States)

    Cocks, F. H.; Harman, C. M.; Klenk, P. A.; Simmons, W. N.

    Acting as a virtual first stage, a hypervelocity launch together with the use of frozen hydrogen/frozen oxygen propellant, offers a Single-Stage-To-Orbit (SSTO) system that promises an enormous increase in SSTO mass-ratio. Ram acceleration provides hypervelocity (2 km/sec) to the orbital vehicle with a gas gun supplying the initial velocity required for ram operation. The vehicle itself acts as the center body of a ramjet inside a launch tube, filled with gaseous fuel and oxidizer, acting as an engine cowling. The high acceleration needed to achieve hypervelocity precludes a crew, and it would require greatly increased liquid fuel tank structural mass if a liquid propellant is used for post-launch vehicle propulsion. Solid propellants do not require as much fuel- chamber strengthening to withstand a hypervelocity launch as do liquid propellants, but traditional solid fuels have lower exhaust velocities than liquid hydrogen/liquid oxygen. The shock-stability of frozen hydrogen/frozen oxygen propellant has been experimentally demonstrated. A hypervelocity launch system using frozen hydrogen/frozen oxygen propellant would be a revolutionary new development in spaceflight.

  18. Calculation of Rydberg interaction potentials

    DEFF Research Database (Denmark)

    Weber, Sebastian; Tresp, Christoph; Menke, Henri

    2017-01-01

    for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up...... to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source....

  19. Excitation of helium Rydberg states and doubly excited resonances in strong extreme ultraviolet fields: Full-dimensional quantum dynamics using exponentially tempered Gaussian basis sets

    Czech Academy of Sciences Publication Activity Database

    Kaprálová-Žďánská, Petra Ruth; Šmydke, Jan; Civiš, S.

    2013-01-01

    Roč. 139, č. 10 (2013), s. 104314 ISSN 0021-9606 R&D Projects: GA AV ČR IAAX00100903; GA MŠk(CZ) ME10046; GA ČR GAP205/11/0571 Institutional support: RVO:68378271 Keywords : Gaussian distribution * helium * oscillator strengths * quantum chemistry * rotational states * Rydberg states * two-photon processes Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.122, year: 2013

  20. Systematics in Rydberg state excitations for ion-atom collisions

    International Nuclear Information System (INIS)

    Andresen, B.; Jensen, K.; Petersen, N.B.; Veje, E.

    1976-01-01

    Rydberg state excitations in the Ne + , Mg + -He collisions have been studied in the projectile energy range 10-75 keV by means of optical spectrometry in a search for systematic trends. The relative excitation cross sections for levels of a Rydberg term series are found to follow a general (nsup(x))sup(P) behaviour with P < approximately -3 varying with collision energy and particles, regardless of whether the excited state population results from direct excitation, single electron transfer, or double electron transfer. At higher collision energies P is approximately -3 as predicted by theory. Polarization of the emitted line radiation indicates that there is no general rule for the relative excitation of the different magnetic substates of the same level. A statistical distribution of excitation is found for levels within the same term when the fine structure splitting is small. (Auth.)

  1. Mean-field energy-level shifts and dielectric properties of strongly polarized Rydberg gases

    OpenAIRE

    Zhelyazkova, V.; Jirschik, R.; Hogan, S. D.

    2016-01-01

    Mean-field energy-level shifts arising as a result of strong electrostatic dipole interactions within dilute gases of polarized helium Rydberg atoms have been probed by microwave spectroscopy. The Rydberg states studied had principal quantum numbers n=70 and 72, and electric dipole moments of up to 14 050 D, and were prepared in pulsed supersonic beams at particle number densities on the order of 108 cm−3. Comparisons of the experimental data with the results of Monte Carlo calculations highl...

  2. MgH Rydberg series: Transition energies from electron propagator theory and oscillator strengths from the molecular quantum defect orbital method

    Science.gov (United States)

    Corzo, H. H.; Velasco, A. M.; Lavín, C.; Ortiz, J. V.

    2018-02-01

    Vertical excitation energies belonging to several Rydberg series of MgH have been inferred from 3+ electron-propagator calculations of the electron affinities of MgH+ and are in close agreement with experiment. Many electronically excited states with n > 3 are reported for the first time and new insight is given on the assignment of several Rydberg series. Valence and Rydberg excited states of MgH are distinguished respectively by high and low pole strengths corresponding to Dyson orbitals of electron attachment to the cation. By applying the Molecular Quantum Defect Orbital method, oscillator strengths for electronic transitions involving Rydberg states also have been determined.

  3. Ionization Spectroscopic Measurement of nP Rydberg Levels of 87Rb Cold Atoms

    Science.gov (United States)

    Li, Yufan; Zaheeruddin, Syed; Zhao, Dongmei; Ma, Xinwen; Yang, Jie

    2018-05-01

    We created an ultracold plasma via the spontaneous ionization of cold dense Rydberg atoms of 87Rb in a magneto-optical trap (MOT), and measured the nS1/2 (n = 50-80), nP1/2 (n = 16-23), nP3/2 (n = 16-98), and nD5/2 (n = 49-96) Rydberg levels by detecting the electrons in the ultracold plasma. By fitting the energy levels of Rydberg states, the first ionization potential of 33690.950(11) cm-1 and the quantum defects of S, P, and D orbitals were obtained. The absolute transition energies of nS1/2 (n = 66-80), nP1/2 (n = 16-23), nP3/2 (n = 16-98), and nD5/2 (n = 58-96) states of 87Rb, as well as the quantum defects for p1/2 and p3/2 series, are given for the first time.

  4. Lithium atoms on helium nanodroplets: Rydberg series and ionization dynamics

    Science.gov (United States)

    Lackner, Florian; Krois, Günter; Ernst, Wolfgang E.

    2017-11-01

    The electronic excitation spectrum of lithium atoms residing on the surface of helium nanodroplets is presented and analyzed employing a Rydberg-Ritz approach. Utilizing resonant two-photon ionization spectroscopy, two different Rydberg series have been identified: one assigned to the nS(Σ) series and the other with predominantly nP(Π) character. For high Rydberg states, which have been resolved up to n = 13, the surrounding helium effectively screens the valence electron from the Li ion core, as indicated by the apparent red-shift of Li transitions and lowered quantum defects on the droplet with respect to their free atom counterparts. For low n states, the screening effect is weakened and the prevailing repulsive interaction gives rise to strongly broadened and blue-shifted transitions. The red-shifts originate from the polarization of nearby He atoms by the positive Li ion core. As a consequence of this effect, the ionization threshold is lowered by 116 ± 10 cm-1 for Li on helium droplets with a radius of about 40 Å. Upon single-photon ionization, heavy complexes corresponding to Li ions attached to intact helium droplets are detected. We conclude that ionization close to the on-droplet ionization threshold triggers a dynamic process in which the Li ion core undergoes a transition from a surface site into the droplet.

  5. Alkali Rydberg states in electromagnetic fields: computational physics meets experiment

    International Nuclear Information System (INIS)

    Krug, A.

    2001-11-01

    We study highly excited hydrogen and alkali atoms ('Rydberg states') under the influence of a strong microwave field. As the external frequency is comparable to the highly excited electron's classical Kepler frequency, the external field induces a strong coupling of many different quantum mechanical energy levels and finally leads to the ionization of the outer electron. While periodically driven atomic hydrogen can be seen as a paradigm of quantum chaotic motion in an open (decaying) quantum system, the presence of the non-hydrogenic atomic core - which unavoidably has to be treated quantum mechanically - entails some complications. Indeed, laboratory experiments show clear differences in the ionization dynamics of microwave driven hydrogen and non-hydrogenic Rydberg states. In the first part of this thesis, a machinery is developed that allows for numerical experiments on alkali and hydrogen atoms under precisely identical laboratory conditions. Due to the high density of states in the parameter regime typically explored in laboratory experiments, such simulations are only possible with the most advanced parallel computing facilities, in combination with an efficient parallel implementation of the numerical approach. The second part of the thesis is devoted to the results of the numerical experiment. We identify and describe significant differences and surprising similarities in the ionization dynamics of atomic hydrogen as compared to alkali atoms, and give account of the relevant frequency scales that distinguish hydrogenic from non-hydrogenic ionization behavior. Our results necessitate a reinterpretation of the experimental results so far available, and solve the puzzle of a distinct ionization behavior of periodically driven hydrogen and non-hydrogenic Rydberg atoms - an unresolved question for about one decade. Finally, microwave-driven Rydberg states will be considered as prototypes of open, complex quantum systems that exhibit a complicated temporal decay

  6. Electric Dipole Echoes in Rydberg Atoms

    International Nuclear Information System (INIS)

    Yoshida, S.; Reinhold, C. O.; Burgdoerfer, J.; Zhao, W.; Mestayer, J. J.; Lancaster, J. C.; Dunning, F. B.

    2007-01-01

    We report the first observation of echoes in the electric dipole moment of an ensemble of Rydberg atoms precessing in an external electric field F. Rapid reversal of the field direction is shown to play a role similar to that of a π pulse in NMR in rephasing a dephased ensemble of electric dipoles resulting in the buildup of an echo. The mechanisms responsible for this are discussed with the aid of classical trajectory Monte Carlo simulations

  7. Motion of Rydberg atoms with strong permanent-electric-dipole interactions

    International Nuclear Information System (INIS)

    Gonçalves, Luís Felipe; Thaicharoen, Nithiwadee; Raithel, Georg

    2016-01-01

    Using classical trajectories simulations, we investigate the dynamics of a cold sample of Rydberg atoms with high permanent electric dipole moments. The dipolar state can be created using an adiabatic passage through an avoided crossing between an S-like state and a linear Stark state. The simulations yield the pair-correlation functions (PCF) of the atom samples, which allow us to extract the motion of Rydberg-atom pairs in the many-body system. The results reveal the strength and the anisotropic character of the underlying interaction. The simulation is employed to test the suitability of experimental methods designed to derive interaction parameters from PCF. Insight is obtained about the stability of the method against variation of experimentally relevant parameters. Transient correlations due to interaction-induced heating are observed. (paper)

  8. A theoretical investigation of valence and Rydberg electronic states of acrolein

    International Nuclear Information System (INIS)

    Aquilante, Francesco; Barone, Vincenzo; Roos, Bjoern O.

    2003-01-01

    The main features of the ultraviolet spectrum of acrolein have been studied by a multireference perturbative treatment and by a time dependent density functional approach. The valence and Rydberg transition energies have been calculated and the assignment of the experimental bands has been clarified. The different relaxation trends of the three lowest singlet and triplet excited states have been analyzed by unconstrained geometry optimizations. This has allowed, in particular, the characterization of a twisted 3 (ππ*) state, which is crucial for the interesting photophysics and photochemistry of the acrolein molecule and, more generally, of the α,β-enones. Solvatochromic shifts in aqueous solution have been investigated using a combined discrete/continuum approach based on the so called polarizable continuum model. The experimental trends are well reproduced by this approach and a closer degeneracy in the triplet manifold has been detected in solution with respect to gas phase

  9. Investigation by high resolution electron spectroscopy of the helium-like 3lnl' Rydberg series in double capture processes at low collision velocity: auto transfer to Rydberg states and electron stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Gonzalez, A.; Benhenni, M. (Toulouse-3 Univ., 31 (France)); Bachau, H.; Sanchez, I. (Bordeaux-1 Univ., 33 - Talence (France). Lab. des Collisions Atomiques)

    1994-09-28

    A high resolution electron spectrometry of the (3lnl') Ryberg series populated in N[sup 7+] + He and Ne[sup 10+] + He collisions at 10 q keV, 10[sup o] allows us to observe, for the first time by this method, two post-collisional effects. First, it is found with nitrogen ions that, when n increases from n = 4 to 9, the L-distribution peaks more and more on the high angular momentum states. This is qualitatively understood as a Stark deformation of the Rydberg orbit by the Coulomb field of the receding ion. Also, in the n range where the double capture process populates symmetrical 4l4l' states (n>9), an enhancement of the intensities of the 3lnl' Rydberg lines is observed for both collisonal systems. This is thought to be a signature of the so-called auto transfer to Rydberg states effect. The transfer of population from the 3l4l' to the 3lnl' states is found to be favoured against a direct autoionization of these 4l4l' states into the n = 2 continuum. These experimental findings together with preliminary spectroscopic calculations concerning the configuration interaction of the Ne[sup 8+] (4l4l') states with the Ne[sup 8+](3lnl') Rydberg series are also discussed within the context of the electron stabilization which follows a double capture. (Author).

  10. Rydberg gas theory of a glow discharge plasma: I. Application to the electrical behaviour of a fast flowing glow discharge plasma.

    Science.gov (United States)

    Mason, Rod S; Mitchell, David J; Dickinson, Paul M

    2010-04-21

    model, the complex electrical (and mass spectrometric) behaviour fits qualitatively, but can be understood well, with the Rydberg gas model described in papers II and III (R. S. Mason, and R. S. Mason and P. Douglas, PCCP, 2010, DOI: 10.1039/b918081h and b918083d) over a wide range of probe bias voltages. The full cycle of behavior is then described for the development of a true secondary discharge within the downstream plasma.

  11. Analytical investigation of one-dimensional Rydberg atoms interacting with half-cycle pulses

    International Nuclear Information System (INIS)

    Bersons, I.; Veilande, R.

    2004-01-01

    Classical, quantum-mechanical, and semiclassical expressions for the transition probability in one-dimensional Rydberg atom irradiated by short half-cycle pulse are derived and compared. The simple formulas obtained for excitation of Rydberg atom by two time delayed weak half-cycle pulses reproduce well the experimental data and the solutions of time-dependent Schroedinger equation. When the transferred momenta are stronger and positive, the transition probabilities exhibit fast oscillations with time delay between the pulses. The classical transition probability is constant in time. For negative transferred momenta a focusing phenomenon is observed, and there is a region in time delay, where the transition probabilities oscillate with the Kepler period

  12. Hydrogen Balmer series measurements and determination of Rydberg's constant using two different spectrometers

    International Nuclear Information System (INIS)

    Amrani, D

    2014-01-01

    This paper investigates the use of two different methods, the optical and the computer-aided diffraction-grating spectrometer, to measure the wavelength of visible lines of Balmer series from the hydrogen atomic spectrum and estimate the value of Rydberg's constant. Analysis and interpretation of data showed that both methods, despite their difference in terms of the type of equipment used, displayed good performance in terms of precision of measurements of wavelengths of spectral lines. A comparison was carried out between the experimental value of Rydberg's constant obtained with both methods and the accepted value. The results of Rydberg's constant obtained with both the optical and computer-aided spectrometers were 1.099 28 × 10 −7  m −1  and 1.095 13 × 10 −7  m −1  with an error difference of 0.17% and 0.20% compared to the accepted value 1.097 373 × 10 −7  m −1 , respectively. (paper)

  13. Creating high-purity angular-momentum-state Rydberg atoms by a pair of unipolar laser pulses

    Science.gov (United States)

    Xin, PeiPei; Cheng, Hong; Zhang, ShanShan; Wang, HanMu; Xu, ZiShan; Liu, HongPing

    2018-04-01

    We propose a method of producing high-purity angular-momentum-state Rydberg atoms by a pair of unipolar laser pulses. The first positive-polarity optical half-cycle pulse is used to prepare an excited-state wave packet while the second one is less intense, but with opposite polarity and time delayed, and is employed to drag back the escaping free electron and clip the shape of the bound Rydberg wave packet, selectively increasing or decreasing a fraction of the angular-momentum components. An intelligent choice of laser parameters such as phase and amplitude helps us to control the orbital-angular-momentum composition of an electron wave packet with more facility; thus, a specified angular-momentum state with high purity can be achieved. This scheme of producing high-purity angular-momentum-state Rydberg atoms has significant application in quantum-information processing.

  14. From the Rydberg constant to the fundamental constants metrology

    International Nuclear Information System (INIS)

    Nez, F.

    2005-06-01

    This document reviews the theoretical and experimental achievements of the author since the beginning of his scientific career. This document is dedicated to the spectroscopy of hydrogen, deuterium and helium atoms. The first part is divided into 6 sub-sections: 1) the principles of hydrogen spectroscopy, 2) the measurement of the 2S-nS/nD transitions, 3) other optical frequency measurements, 4) our contribution to the determination of the Rydberg constant, 5) our current experiment on the 1S-3S transition, 6) the spectroscopy of the muonic hydrogen. Our experiments have improved the accuracy of the Rydberg Constant by a factor 25 in 15 years and we have achieved the first absolute optical frequency measurement of a transition in hydrogen. The second part is dedicated to the measurement of the fine structure constant and the last part deals with helium spectroscopy and the search for optical references in the near infrared range. (A.C.)

  15. Cavity quantum electrodynamics with a Rydberg-blocked atomic ensemble

    DEFF Research Database (Denmark)

    Guerlin, Christine; Brion, Etienne; Esslinger, Tilman

    2010-01-01

    The realization of a Jaynes-Cummings model in the optical domain is proposed for an atomic ensemble. The scheme exploits the collective coupling of the atoms to a quantized cavity mode and the nonlinearity introduced by coupling to high-lying Rydberg states. A two-photon transition resonantly cou...

  16. Survival of Rydberg atoms in intense laser fields and the role of nondipole effects

    Science.gov (United States)

    Klaiber, Michael; Dimitrovski, Darko

    2015-02-01

    We consider the interaction of Rydberg atoms with strong infrared laser pulses using an approach based on the Magnus expansion of the time evolution operator. First-order corrections beyond the electric dipole approximation are also included in the theory. We illustrate the dynamics of the interaction at the parameters of the experiment [Eichmann et al., Phys. Rev. Lett. 110, 203002 (2013), 10.1103/PhysRevLett.110.203002]. It emerges that the depletion of Rydberg atoms in this regime comes predominantly from the nondipole effects.

  17. Rydberg states of chloroform studied by VUV photoabsorption spectroscopy

    Science.gov (United States)

    Singh, Param Jeet; Shastri, Aparna; D'Souza, R.; Jagatap, B. N.

    2013-11-01

    The VUV photoabsorption spectra of CHCl3 and CDCl3 in the energy region 6.2-11.8 eV (50,000-95,000 cm-1) have been investigated using synchrotron radiation from the Indus-1 source. Rydberg series converging to the first four ionization limits at 11.48, 11.91, 12.01 and 12.85 eV corresponding to excitation from the 1a2, 4a1, 4e, 3e, orbitals of CHCl3 respectively are identified and analyzed. Quantum defect values are observed to be consistent with excitation from the chlorine lone pair orbitals. Vibrational progressions observed in the region of 72,500-76,500 cm-1 have been reassigned to ν3 and combination modes of ν3+ν6 belonging to the 1a2→4p transition in contrast to earlier studies where they were assigned to a ν3 progression superimposed on the 3e→4p Rydberg transition. The assignments are further confirmed based on isotopic substitution studies on CDCl3 whose VUV photoabsorption spectrum is reported here for the first time. The frequencies of the ν3 and ν6 modes in the 4p Rydberg state of CHCl3 (CDCl3) are proposed to be ~454 (409) cm-1 and~130 (129) cm-1 respectively based on the vibronic analysis. DFT calculations of neutral and ionic ground state vibrational frequencies support the vibronic analysis. Experimental spectrum is found to be in good agreement with that predicted by TDDFT calculations. This work presents a consolidated analysis of the VUV photoabsorption spectrum of chloroform.

  18. Radiative lifetime measurements of rubidium Rydberg states

    International Nuclear Information System (INIS)

    Branden, D B; Juhasz, T; Mahlokozera, T; Vesa, C; Wilson, R O; Zheng, M; Tate, D A; Kortyna, A

    2010-01-01

    We have measured the radiative lifetimes of ns, np and nd Rydberg states of rubidium in the range 28 ≤ n ≤ 45. To enable long-lived states to be measured, our experiment uses slow-moving (∼100 μK) 85 Rb atoms in a magneto-optical trap (MOT). Two experimental techniques have been adopted to reduce random and systematic errors. First, a narrow-bandwidth pulsed laser is used to excite the target nl Rydberg state, resulting in minimal shot-to-shot variation in the initial state population. Second, we monitor the target state population as a function of time delay from the laser pulse using a short-duration, millimetre-wave pulse that is resonant with a one- or two-photon transition to a higher energy 'monitor state', n'l'. We then selectively field ionize the monitor state, and detect the resulting electrons with a micro-channel plate. This signal is an accurate mirror of the nl target state population, and is uncontaminated by contributions from other states which are populated by black body radiation. Our results are generally consistent with other recent experimental results obtained using a method which is more prone to systematic error, and are also in excellent agreement with theory.

  19. New innershell phenomena from Rydberg series of highly charged ions

    International Nuclear Information System (INIS)

    Rosmej, F.B.

    1997-01-01

    Dielectronic satellite spectra near the He-like resonance line W are investigated experimentally and theoretically. We propose that under certain plasma conditions the resonance line structure plays a minor role and can be mixed with the accumulation of Rydberg satellites. (orig.)

  20. Topological matter with collective encoding and Rydberg blockade

    DEFF Research Database (Denmark)

    Nielsen, Anne E. B.; Mølmer, Klaus

    2010-01-01

    We propose to use a permutation symmetric sample of multilevel atoms to simulate the properties of topologically ordered states. The Rydberg blockade interaction is used to prepare states of the sample which are equivalent to resonating valence bond states, Laughlin states, and string-net condens......-net condensates and to create and study the properties of their quasi-particle-like fundamental excitations....

  1. l- and n-changing collisions during interaction of a pulsed beam of Li Rydberg atoms with CO2

    Science.gov (United States)

    Dubreuil, B.; Harnafi, M.

    1989-07-01

    The pulsed Li atomic beam produced in our experiment is based on controlled transversely-excited-atmospheric CO2 laser-induced ablation of a Li metal target. The atomic beam is propagated in vacuum or in CO2 gas at low pressure. Atoms in the beam are probed by laser-induced fluorescence spectroscopy. This allows the determination of time-of-flight and velocity distributions. Li Rydberg states (n=5-13) are populated in the beam by two-step pulsed-laser excitation. The excited atoms interact with CO2 molecules. l- and n-changing cross sections are deduced from the time evolution of the resonant or collision-induced fluorescence following this selective excitation. l-changing cross sections of the order of 104 AṦ are measured; they increase with n as opposed to the plateau observed for Li* colliding with a diatomic molecule. This behavior is qualitatively well explained in the framework of the free-electron model. n-->n' changing processes with large cross sections (10-100 AṦ) are also observed even in the case of large electronic energy change (ΔEnn'>103 cm-1). These results can be interpreted in terms of resonant-electronic to vibrational energy transfers between Li Rydberg states and CO2 vibrational modes.

  2. Population of Rydberg states by electron capture in fast-ion--atom collisions

    International Nuclear Information System (INIS)

    Burgdoerfer, J.; Dube, L.J.

    1985-01-01

    The l,m-substate distribution in low-lying Rydberg manifolds (nroughly-equal10) following electron capture H + +H(1s)→H(n)+H + is calculated at high velocities (v>1 a.u.) in the continuum-distorted-wave (CDW) approximation. The standard CDW approximation is modified to account for final-state Stark mixing of the Rydberg manifold in the exit channel using the post-collision-interaction model. The influence of multiple-scattering contributions is analyzed and comparison is made with sigma/sub l/m predicted by the Born approximation. We find that the double-scattering contribution, closely connected with the classical Thomas process, becomes visible in the CDW approximation at surprisingly low nonasymptotic velocities

  3. Laser diagnostics of the energy spectrum of Rydberg states of the lithium-7 atom

    Energy Technology Data Exchange (ETDEWEB)

    Zelener, B. B., E-mail: bobozel@mail.ru; Saakyan, S. A.; Sautenkov, V. A.; Manykin, E. A.; Zelener, B. V.; Fortov, V. E. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2015-12-15

    The spectra of excited lithium-7 atoms prepared in a magneto-optical trap are studied using a UV laser. The laser diagnostics of the energy of Rydberg atoms is developed based on measurements of the change in resonance fluorescence intensity of ultracold atoms as the exciting UV radiation frequency passes through the Rydberg transition frequency. The energies of various nS configurations are obtained in a broad range of the principal quantum number n from 38 to 165. The values of the quantum defect and ionization energy obtained in experiments and predicted theoretically are discussed.

  4. Magnetic resonance of field-frozen and zero-field-frozen magnetic fluids

    International Nuclear Information System (INIS)

    Pereira, A.R.; Pelegrini, F.; Neto, K. Skeff; Buske, N.; Morais, P.C.

    2004-01-01

    In this study magnetic resonance was used to investigate magnetic fluid samples frozen under zero and non-zero (15 kG) external fields. The magnetite-based sample containing 2x10 17 particle/cm 3 was investigated from 100 to 400 K. Analysis of the temperature dependence of the resonance field revealed bigger magnetic structures in the frozen state than in the liquid phase. Also, differences in the mesoscopic organization in the frozen state may explain the data obtained from samples frozen under zero and non-zero fields

  5. New innershell phenomena from Rydberg series of highly charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Rosmej, F.B. [Bochum Univ. (Germany). Inst. fuer Experimentalphysik; Faenov, A.Ya. [MISDC, VNIIFTRI, Mendeleevo (Russian Federation)

    1997-12-31

    Dielectronic satellite spectra near the He-like resonance line W are investigated experimentally and theoretically. We propose that under certain plasma conditions the resonance line structure plays a minor role and can be mixed with the accumulation of Rydberg satellites. (orig.). 7 refs.

  6. The Closed-Orbit Theory for General Rydberg Atoms in External Fields

    International Nuclear Information System (INIS)

    Carboni, R.

    1997-01-01

    The photoabsorption spectra of hydrogen Rydberg atoms, as well of model Rydberg atoms in pure magnetic or electric fields have been successfully calculated using the semiclassical closed-orbit theory. The theory relates the resonances of the spectra to closed classical orbits of the excited electron. The dynamics of multielectron atoms is more complicated than the hydrogenic one; additionally, when the atoms are in the presence of perpendicular magnetic and electric fields becomes more complex than when they are in pure fields, due to the fact that the Hamiltonian is non-separable in three degrees of freedom, instead of two non-separable degrees of freedom. In this work, I present an extension of the closed-orbit theory to three degrees of freedom, considering arbitrary quantum defects, i.e., general atoms. (Author) [es

  7. Experimental studies of pipeline uplift resistance in frozen ground

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.; Crooks, J. [Golder Associates Ltd., Calgary, AB (Canada); Nixon, J.F. [Nixon Geotech Ltd., Calgary, AB (Canada); Zhou, J. [TransCanada PipeLines Ltd., Calgary, AB (Canada)

    2004-07-01

    Gas pipelines buried in permafrost are subjected to the mechanisms of frost heave and thaw settlement which induce movement in the pipe. The magnitude of loads depend on the relative displacement and the load-displacement characteristics of the surrounding soils. This paper presented the results of laboratory tests that investigated the geomechanical properties and uplift resistance of frozen Calgary silt. Compacted soil was frozen 24 hours prior to the uplift testing. A thick-wall steel pipe was laid down and more soil was subsequently placed and compacted around and above the pipe until the desired burial depth was achieved. The temperature of the frozen soil was monitored along with deformations of the soil surface in order to determine the impact of loading rate, ice content and freezing direction. The geomechanical tests included triaxial compression tests as well as tensile and creep tests. The stiffness, tensile strain limits and time dependent behaviour of the frozen soil were also defined. The issue of crack development in the frozen soil was addressed and a numerical model was developed based on measured load-displacement relationships and geomechanical properties of the frozen soil. Bilinear stress-strain relationships were consistently noted for the frozen samples under triaxial compression. The stress-strain behaviour was found to be independent of the confining stress. The measured tensile limits were found to be in good agreement with published literature. Peak uplift resistance and post-peak decreases were consistently noted in the uplift resistance. Tensile fractures were observed vertically above the crown of the pipe. Uplift resistance was highly affected by the loading rate, but the load-displacement curve prior to the peak was not affected by radial freezing or ice lenses. A new peak uplift resistance was reached following the freeze/thaw cycle, suggesting the healing of the tensile fractures. 9 refs., 1 tab., 11 figs.

  8. Ionization of nS, nP, and nD lithium, potassium, and cesium Rydberg atoms by blackbody radiation

    Science.gov (United States)

    Beterov, I. I.; Ryabtsev, I. I.; Tretyakov, D. B.; Bezuglov, N. N.; Ékers, A.

    2008-07-01

    The results of theoretical calculations of the blackbody ionization rates of lithium, potassium, and cesium atoms residing in Rydberg states are presented. The calculations are performed for nS, nP, and nD states in a wide range of principal quantum numbers, n = 8-65, for blackbody radiation temperatures T = 77, 300, and 600 K. The calculations are performed using the known quasi-classical formulas for the photoionization cross sections and for the radial matrix elements of transitions in the discrete spectrum. The effect of the blackbody-radiation-induced population redistribution between Rydberg states on the blackbody ionization rates measured under laboratory conditions is quantitatively analyzed. Simple analytical formulas that approximate the numerical results and that can be used to estimate the blackbody ionization rates of Rydberg atoms are presented. For the S series of lithium, the rate of population of high-lying Rydberg levels by blackbody radiation is found to anomalously behave as a function of n. This anomaly is similar to the occurrence of the Cooper minimum in the discrete spectrum.

  9. Dissipative preparation of steady Greenberger-Horne-Zeilinger states for Rydberg atoms with quantum Zeno dynamics

    Science.gov (United States)

    Shao, X. Q.; Wu, J. H.; Yi, X. X.; Long, Gui-Lu

    2017-12-01

    Inspired by a recent work [F. Reiter, D. Reeb, and A. S. Sørensen, Phys. Rev. Lett. 117, 040501 (2016), 10.1103/PhysRevLett.117.040501], we present a simplified proposal for dissipatively preparing a Greenberger-Horne-Zeilinger (GHZ) state of three Rydberg atoms in a cavity. The Z pumping is implemented under the action of the spontaneous emission of Λ -type atoms and the quantum Zeno dynamics induced by strong continuous coupling. In the meantime, a dissipative Rydberg pumping breaks up the stability of the state | GHZ+〉 in the process of Z pumping, making | GHZ-〉 the unique steady state of the system. Compared with the former scheme, the number of driving fields acting on atoms is greatly reduced and only a single-mode cavity is required. The numerical simulation of the full master equation reveals that a high fidelity ˜98 % can be obtained with the currently achievable parameters in the Rydberg-atom-cavity system.

  10. Electronic structure of molecular Rydberg states of some small molecules and molecular ion

    International Nuclear Information System (INIS)

    Sun Biao; Li Jiaming

    1993-01-01

    Based on an independent-particle-approximation (i.e. the multiple scattering self-consistent-field theory), the electronic structures of Rydberg states of the small diatomic molecules H 2 , He 2 and the He 2 + molecular ion were studied. The principal quantum number of the first state of the Rydberg series is determined from a convention of the limit of the molecular electronic configuration. The dynamics of the excited molecules and molecular ion has been elucidated. The theoretical results are in fair agreement with the existing experimental measurements, thus they can serve as a reliable basis for future refined treatment such as the configuration interaction calculation

  11. 21 CFR 101.95 - “Fresh,” “freshly frozen,” “fresh frozen,” “frozen fresh.”

    Science.gov (United States)

    2010-04-01

    ... freezing will not preclude use of the term “fresh frozen” to describe the food. “Quickly frozen” means... 21 Food and Drugs 2 2010-04-01 2010-04-01 false âFresh,â âfreshly frozen,â âfresh frozen,â âfrozen fresh.â 101.95 Section 101.95 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  12. Experiments with Rydberg atoms on a current-carrying atom chip

    NARCIS (Netherlands)

    Cisternas San Martín, N.V.

    2018-01-01

    On one side, atom-chip experiments have demonstrated to be a versatile tool to study quantum physics in cold atoms systems. On the other side, Rydberg atoms have exaggerated properties that makes them good candidates to study quantum information and quantum simulations protocols. In this thesis both

  13. An investigation of electronic states of some molecules and molecular cations using mass analyzed threshold ionization and photoinduced Rydberg ionization spectroscopy

    Science.gov (United States)

    Hofstein, Jason David

    1999-11-01

    Mass analyzed threshold ionization (MATI) experiments have enabled mapping of the n-dependent Rydberg state survival probability for a series of molecules. Utilizing vacuum and extreme ultraviolet (VUV/XUV) photons, one photon Rydberg manifold spectra of argon, hydrogen chloride, nitrogen, benzene, and oxygen were produced, and the prospects of photoinduced Rydberg ionization (PIRI) experiments examined. It was found that the widths of Rydberg manifolds for the molecules studied are quite different. Hydrogen chloride and nitrogen have the narrowest manifold width, followed by benzene, and then oxygen. These varying widths are most strongly correlated with the angular momentum (i.e., quantum defect) of the initially prepared Rydberg orbital. PIRI experiments required the use of a static cell, rather than a molecular jet assembly, for the more efficient production of higher amounts of VUV/XUV radiation, and hence more Rydberg signal needed to observe PIRI. Armed with the ability to produce tunable VUV/XUV radiation, and to determine the feasibility of a PIRI experiment, the MATI and fragment PIRI spectra of trans-1,3-butadiene (BD) were recorded. The MATI spectrum is vibrationally resolved and was analyzed with the help of ab initio calculations and other published results. The fragment PIRI spectrum of the Aproduction of C3H3+ dominates, but at higher photon energies, C2H4 + is also produced. The production of each fragment showed a definite PIRI wavelength dependence.

  14. Role of ion-pair states in the predissociation dynamics of Rydberg states of molecular iodine.

    Science.gov (United States)

    von Vangerow, J; Bogomolov, A S; Dozmorov, N V; Schomas, D; Stienkemeier, F; Baklanov, A V; Mudrich, M

    2016-07-28

    Using femtosecond pump-probe ion imaging spectroscopy, we establish the key role of I(+) + I(-) ion-pair (IP) states in the predissociation dynamics of molecular iodine I2 excited to Rydberg states. Two-photon excitation of Rydberg states lying above the lowest IP state dissociation threshold (1st tier) is found to be followed by direct parallel transitions into IP states of the 1st tier asymptotically correlating to a pair of I ions in their lowest states I(+)((3)P2) + I(-)((1)S0), of the 2nd tier correlating to I(+)((3)P0) + I(-)((1)S0), and of the 3rd tier correlating to I(+)((1)D2) + I(-)((1)S0). Predissociation via the 1st tier proceeds presumably with a delay of 1.6-1.7 ps which is close to the vibrational period in the 3rd tier state (3rd tier-mediated process). The 2nd tier IP state is concluded to be the main precursor for predissociation via lower lying Rydberg states proceeding with a characteristic time of 7-8 ps and giving rise to Rydberg atoms I(5s(2)5p(4)6s(1)). The channel generating I((2)P3/2) + I((2)P1/2) atoms with total kinetic energy corresponding to one-photon excitation is found to proceed via a pump - dump mechanism with dramatic change of angular anisotropy of this channel as compared with earlier nanosecond experiments.

  15. Quantum localization of the kicked rydberg atom

    Science.gov (United States)

    Yoshida; Reinhold; Burgdorfer

    2000-03-20

    We investigate the quantum localization of the one-dimensional Rydberg atom subject to a unidirectional periodic train of impulses. For high frequencies of the train the classical system becomes chaotic and leads to fast ionization. By contrast, the quantum system is found to be remarkably stable. We find this quantum localization to be directly related to the existence of "scars" of the unstable periodic orbits of the system. The localization length is given by the energy excursion along the periodic orbits.

  16. Coherent excitation of a single atom to a Rydberg state

    DEFF Research Database (Denmark)

    Miroshnychenko, Yevhen; Gaëtan, Alpha; Evellin, Charles

    2010-01-01

    We present the coherent excitation of a single Rubidium atom to the Rydberg state 58d3/2 using a two-photon transition. The experimental setup is described in detail, as are experimental techniques and procedures. The coherence of the excitation is revealed by observing Rabi oscillations between...

  17. Ionization of Rb Rydberg atoms in the attractive nsnp dipole-dipole potential

    International Nuclear Information System (INIS)

    Park, Hyunwook; Shuman, E. S.; Gallagher, T. F.

    2011-01-01

    We have observed the ionization of a cold gas of Rb Rydberg atoms which occurs when nsns van der Waals pairs of ns atoms of n≅ 40 on a weakly repulsive potential are transferred to an attractive dipole-dipole nsnp potential by a microwave transition. Comparing the measurements to a simple model shows that the initial 300-μK thermal velocity of the atoms plays an important role. Excitation to a repulsive dipole-dipole potential does not lead to more ionization on a 15-μs time scale than leaving the atoms in the weakly repulsive nsns state. This observation is slightly surprising since a radiative transition must occur to allow ionization in the latter case. Finally, by power broadening of the microwave transition, to allow transitions from the initial nsns state to the nsnp state over a broad range of internuclear spacings, it is possible to accelerate markedly the evolution to a plasma.

  18. Systematic observation of tunneling field-ionization in highly excited Rb Rydberg atoms

    International Nuclear Information System (INIS)

    Kishimoto, Y.; Tada, M.; Kominato, K.; Shibata, M.; Yamada, S.; Haseyama, T.; Ogawa, I.; Funahashi, H.; Yamamoto, K.; Matsuki, S.

    2002-01-01

    Pulsed field ionization of high-n (90≤n≤150) manifold states in Rb Rydberg atoms has been investigated in high slew-rate regime. Two peaks in the field ionization spectra were systematically observed for the investigated n region, where the field values at the lower peak do not almost depend on the excitation energy in the manifold, while those at the higher peak increase with increasing excitation energy. The fraction of the higher peak component to the total ionization signals increases with increasing n, exceeding 80% at n=147. Characteristic behavior of the peak component and the comparison with theoretical predictions indicate that the higher peak component is due to the tunneling process. The obtained results show that the tunneling process plays increasingly the dominant role at such highly excited nonhydrogenic Rydberg atoms

  19. Experimental efforts at NIST towards one-electron ions in circular Rydberg states

    International Nuclear Information System (INIS)

    Tan, Joseph N; Guise, Nicholas D; Brewer, Samuel M

    2011-01-01

    Experimental effort is underway at NIST to enable tests of theory with one-electron ions synthesized in circular Rydberg states from captured bare nuclei. Problematic effects that limit the accuracy of predicted energy levels for low-lying states are vanishingly small for high-angular-momentum (high-L) states; in particular, the nuclear size correction for high-L states is completely negligible for any foreseeable improvement of measurement precision. As an initial step towards realizing such states, highly charged ions are extracted from the NIST electron beam ion trap (EBIT) and steered through the electrodes of a Penning trap. The goal is to capture bare nuclei in the Penning trap for experiments to make one-electron atoms in circular Rydberg states with dipole (E1) transitions in the optical domain accessible to a frequency comb.

  20. Spin--orbit configuration-interaction study of valence and Rydberg states of LiBe

    International Nuclear Information System (INIS)

    Marino, M.M.; Ermler, W.C.; Kern, C.W.; Bondybey, V.E.

    1992-01-01

    Ab initio spin--orbit full configuration-interaction calculations in the context of relativistic effective core potentials are reported for the weakly bound metal dimer LiBe, a three-valence-electron system. The effects of basis set on the energies of valence and Rydberg states of the cluster are discussed, as are the effects of configuration space selection on the energy of the latter states. Results at the dissociative limit are compared to the experimental atomic spectra. Potential-energy curves and spectroscopic constants are presented for the ground state and fourteen excited states, which includes the Li and Be 2p valence states, the Li 3s, 3p, 3d, and 4s Rydberg states, as well as three low-lying states of the molecular cation

  1. Rydberg dressing of atoms in optical lattices

    Science.gov (United States)

    Macrı, T.; Pohl, T.

    2014-01-01

    We study atoms in optical lattices whose electronic ground state is off-resonantly coupled to a highly excited state with strong binary interactions. We present a time-dependent treatment of the resulting quantum dynamics, which—contrary to recent predictions [36 Li, Ates, and Lesanovsky, Phys. Rev. Lett. 110, 213005 (2013), 10.1103/PhysRevLett.110.213005]—proves that the strong repulsion between the weakly admixed Rydberg states does not lead to atomic trap loss. This finding provides an important basis for creating and manipulating coherent long-range interactions in optical lattice experiments.

  2. Long-term evolution and revival structure of Rydberg wave packets

    International Nuclear Information System (INIS)

    Bluhm, R.

    1995-01-01

    It is known that, after formation, a Rydberg wave packet undergoes a series of collapses and revivals within a time period called the revival time, t rev , at the end of which it is close to its original shape. We study the behavior of Rydberg wave packets on time scales much greater than t rev . We show that after a few revival cycles the wave packet ceases to reform at multiples of the revival time. Instead, a new series of collapses and revivals commences, culminating after a time period t sr >>t rev with the formation of a wave packet that more closely resembles the initial packet than does the full revival at time t rev . Furthermore, at times that are rational fractions of t sr , the square of the autocorrelation function exhibits large peaks with periodicities that can be expressed as fractions of the revival time t rev . These periodicities indicate a new type of fractional revival occurring for times much greater than t rev . A theoretical explanation of these effects is outlined. ((orig.))

  3. Ionization of Rydberg atoms by the kicks of half-cycle pulses

    Indian Academy of Sciences (India)

    2015-11-27

    Home; Journals; Pramana – Journal of Physics; Volume 86; Issue 4. Ionization of Rydberg atoms by the kicks of half-cycle pulses ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015. Guest Editors: ...

  4. 21 CFR 160.110 - Frozen eggs.

    Science.gov (United States)

    2010-04-01

    ... Frozen eggs. (a) Frozen eggs, frozen whole eggs, frozen mixed eggs is the food prepared by freezing... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen eggs. 160.110 Section 160.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  5. Optimal control of Rydberg lattice gases

    Science.gov (United States)

    Cui, Jian; van Bijnen, Rick; Pohl, Thomas; Montangero, Simone; Calarco, Tommaso

    2017-09-01

    We present optimal control protocols to prepare different many-body quantum states of Rydberg atoms in optical lattices. Specifically, we show how to prepare highly ordered many-body ground states, GHZ states as well as some superposition of symmetric excitation number Fock states, that inherit the translational symmetry from the Hamiltonian, within sufficiently short excitation times minimising detrimental decoherence effects. For the GHZ states, we propose a two-step detection protocol to experimentally verify the optimised preparation of the target state based only on standard measurement techniques. Realistic experimental constraints and imperfections are taken into account by our optimisation procedure making it applicable to ongoing experiments.

  6. Optimal control of Rydberg lattice gases

    DEFF Research Database (Denmark)

    Cui, Jian; Bijnen, Rick van; Pohl, Thomas

    2017-01-01

    the translational symmetry from the Hamiltonian, within sufficiently short excitation times minimising detrimental decoherence effects. For the GHZ states, we propose a two-step detection protocol to experimentally verify the optimised preparation of the target state based only on standard measurement techniques....... Realistic experimental constraints and imperfections are taken into account by our optimisation procedure making it applicable to ongoing experiments.......We present optimal control protocols to prepare different many-body quantum states of Rydberg atoms in optical lattices. Specifically, we show how to prepare highly ordered many-body ground states, GHZ states as well as some superposition of symmetric excitation number Fock states, that inherit...

  7. Basic study on promotion of thawing frozen soil by shock loading

    Directory of Open Access Journals (Sweden)

    Toshiaki WATANABE

    2008-06-01

    Full Text Available The aim of study is to confirm a new technique that can crush the frozen soil and/or ice block using underwater shock wave generated by the underwater explosion of explosive. This technique can lead to the earlier sowing, which can have the larger harvest because the duration of sunshine increases. Especially, in Hokkaido prefecture, Japan, if the sowing is carried out in April, we can expect to have 150% of harvest in the ordinary season. In the case of small processing area such as road repairing, frozen soil is thawed by using the heat of gas burner and/or the electric heater. It is not a suitable plan to apply these heating methods to agriculture, from the point of view enormous amount of processing area. Thawing technique for frozen soil is effective against the cold regions, for example, Russia, Norway, and Sweden, etc. At first, we carried out experiments using a detonating fuse and ice block. The propagation process of shock wave into the ice block was observed by means of a high-speed camera. In order to check about that influence we tried to give an actual frozen soil a shock wave. We could get a result that existence of water layer serves an important role in promotion of thawing by the shock loading to the frozen soil.

  8. Energy redistribution in the dissociation of low Rydberg states of HeH and 02

    International Nuclear Information System (INIS)

    Zande, W.J.A. van der.

    1988-01-01

    In this thesis the dissocation process is studied of the diatomic molecules, heliumhydride and molecular oxygen. In ch.'s 2-4 results on the spectroscopy and dissociative decay of the excited states of heliumhydride (HeH) are explained. The positions and dissociation pathways of the A 2 Σ + and B 2 Π states are determined and a theoretical description of the decay of these states are given. An isotope dependent dissociation behaviour of the C 2 /σ + Rydberg state is reported which explained with this theory. In ch.'s 5-7 observations are presented regarding the first Rydberg states of molecular oxygen. The spectroscopy of the (3sσ)d 1 Π g and C 3 Π g states is treated, and the stability and decay of these Rydberg states is discussed qualitatively. An experimental study is described of the (3sσ)d 1 Π g , v=4-8 states. By isotope studies and resolving rotational lines and the measurements of natural linewidths quantitative estimates have been acquired on coupling strengths, positions of repulsive valence states and perturbations reported in literature from REMPI experiments. The electronic coupling strengths between the C 3 Π g state and the 3 Π g valence state has been established. Observed spin-orbit interactions have been quantified and the dissociation of the multiplet states (C 3 Π g , ω=0-2 has been correlated with the multiplet states of the fragment O 3 P J=0-2 . The spectroscopy of the (3sσ3) Rydberg states which con- verge to and are formed in collisions with the O + 2 , a 4 Π μ ion state, is treated. The (3sσ) 5 /π μ state competition between auto-ionizations and (pre-)dissociation has been observed. 207 refs.; 36 figs.; 18 tabs

  9. Effects of enzymes to improve sensory quality of frozen dough bread and analysis on its mechanism.

    Science.gov (United States)

    Wang, Xuan; Pei, Dudu; Teng, Yuefei; Liang, Jianfen

    2018-01-01

    Baking quality of frozen dough is negatively affected by dough weakening and by a reduction in both yeast viability and activity during freezing and frozen storage. The objective of this study was to investigate effects of different enzymes, such as α-amylase, xylanase, celluase, glucose oxidase, and lipase on the texture and sensory quality of bread after frozen storage, as well as on dough properties, in terms of fermentation characteristics, freezable water contents and microstructure. Except for α-amylase, other enzymes improved the bread sensory quality and got higher overall acceptability, especially xylanase. Dough fermentative behavior showed that the maximum heights of frozen dough were increased by 33.2, 19.7 and 7.4%, respectively with xylanase, cellulase and lipase. Cellulase lowered gas holding ability of dough. Thermodynamic properties indicated that addition of enzyme decreased the freezable water contents in frozen dough. Scanning electronic microscopy revealed that freezing and frozen storage disrupted dough gluten network causing separation of starch granules from the gluten matrix. Inclusion of cellulase, xylanase and lipase made the frozen dough having a more continuous gluten network and smoother surface, and glucose oxidase increased the stability of the gluten work.

  10. Implementation of quantum logic gates via Stark-tuned Förster resonance in Rydberg atoms

    Science.gov (United States)

    Huang, Xi-Rong; Hu, Chang-Sheng; Shen, Li-Tuo; Yang, Zhen-Biao; Wu, Huai-Zhi

    2018-02-01

    We present a scheme for implementation of controlled-Z and controlled-NOT gates via rapid adiabatic passage and Stark-tuned Förster resonance. By sweeping the Förster resonance once without passing through it and adiabatically tuning the angle-dependent Rydberg-Rydberg interaction of the dipolar nature, the system can be effectively described by a two-level system with the adiabatic theorem. The single adiabatic passage leads to a gate fidelity as high as 0.999 and a greatly reduced gate operation time. We investigate the scheme by considering an actual atomic level configuration with rubidium atoms, where the fidelity of the controlled-Z gate is still higher than 0.99 under the influence of the Zeeman effect.

  11. Quasi-free scattering in the ionization and destruction of hydrogen and helium Rydberg atoms in collision with neutral targets

    International Nuclear Information System (INIS)

    Renwick, S.P.

    1992-01-01

    Hydrogen and helium Rydberg atoms (H** and He**), with principal quantum number n ranging from 10 to 20, have been used in collision experiments from 1 to 40 keV/amu. These were produced by electron capture in a charge-exchange cell and analyzed by ionization in a modulated electric field combined with phase-sensitive detection. Three experiments have been conducted. In the first, spectra of the band of H and He Rydberg states from electron capture were produced by the modulated field technique and compared. Considerable differences were found between the two. Both types of spectra were analyzed with calculations of Stark energies and field ionization rates. Attempts were made to simulate the spectra using this information and some assumptions about the state distribution produced in the electron capture. In the second experiment, destruction cross sections for H** incident on N 2 , Ar, and SF 6 were measured. This was a further test of the independent-particle model for Rydberg atom scattering; in this model, the atom is destroyed by quasi-free scattering of either the ionic core or the outer electron. Already proven valid for n = 20-35, this has been extended to n as low as 10, as measurements with n = 10 showed full compliance with the model. In the third experiment, not only destruction cross sections but also ionization cross sections for H** and He** incident on Xe, AR, and N 2 were measured. The ionization measurement is a more sensitive test of the quasi-free scattering of the Rydberg electron. This was especially important for the Xe and Ar targets, which exhibits a Ramsauer-Townsend minimum in their free-electron scattering cross sections. The quasi-free Rydberg electron should reproduce these data. Unmistakable deviations from the quasi-free prediction were seen in Xe and N 2 but not in Ar. This represents the first measurement of a breakdown of the Independent Particle Model for fast Rydberg atom scattering

  12. Accurate Mapping of Multilevel Rydberg Atoms on Interacting Spin-1 /2 Particles for the Quantum Simulation of Ising Models

    Science.gov (United States)

    de Léséleuc, Sylvain; Weber, Sebastian; Lienhard, Vincent; Barredo, Daniel; Büchler, Hans Peter; Lahaye, Thierry; Browaeys, Antoine

    2018-03-01

    We study a system of atoms that are laser driven to n D3 /2 Rydberg states and assess how accurately they can be mapped onto spin-1 /2 particles for the quantum simulation of anisotropic Ising magnets. Using nonperturbative calculations of the pair potentials between two atoms in the presence of electric and magnetic fields, we emphasize the importance of a careful selection of experimental parameters in order to maintain the Rydberg blockade and avoid excitation of unwanted Rydberg states. We benchmark these theoretical observations against experiments using two atoms. Finally, we show that in these conditions, the experimental dynamics observed after a quench is in good agreement with numerical simulations of spin-1 /2 Ising models in systems with up to 49 spins, for which numerical simulations become intractable.

  13. Effects of confinement on the Rydberg molecule NeH

    International Nuclear Information System (INIS)

    Lo, J M H; Klobukowski, M; Bielinska-Waz, D; Diercksen, G H F; Schreiner, E W S

    2005-01-01

    Ab initio potential energy curves of the Rydberg NeH molecule in the presence of cylindrical spatial confinement were computed by the method of multi-reference configuration interaction with extended basis sets. The influence of the applied potential to the structures and spectra of the ground and excited states of NeH was analysed in terms of perturbation theory. In addition, the phenomenon of field-induced ionization was discussed

  14. Properties of Ni^+ from microwave spectroscopy of n=9 Rydberg levels of Nickel

    Science.gov (United States)

    Woods, Shannon; Keele, Julie; Smith, Chris; Lundeen, Stephen

    2012-06-01

    The microwave/RESIS method was used to determine the relative positions of 15 of the n=9 Rydberg levels of Nickel with L >= 6. Because the ground state of the Ni^+ ion is a ^2D5/2 level, each Rydberg level (n,L) splits into six eigenstates whose relative positions are determined by long-range e-Ni^+ interactions present in addition to the dominant Coulomb interaction. A previous study with the optical RESIS method determined these positions with precision of +/- 30 MHz [1]. Using the microwave/RESIS method improves that precision by a factor of 300, and leads to much improved determinations of the Ni+ properties that control the long-range interactions. [4pt] [1] Julie A. Keele, Shannon L. Woods, M.E. Hanni, and S.R. Lundeen Phys. Rev. 81, 022506 (2010)

  15. Entanglement of two ground state neutral atoms using Rydberg blockade

    DEFF Research Database (Denmark)

    Miroshnychenko, Yevhen; Browaeys, Antoine; Evellin, Charles

    2011-01-01

    We report on our recent progress in trapping and manipulation of internal states of single neutral rubidium atoms in optical tweezers. We demonstrate the creation of an entangled state between two ground state atoms trapped in separate tweezers using the effect of Rydberg blockade. The quality...... of the entanglement is measured using global rotations of the internal states of both atoms....

  16. Rydberg atoms in weak magnetic fields

    International Nuclear Information System (INIS)

    Kazantsev, A.P.; Pokrovsky, V.L.; Bergou, J.

    1983-01-01

    The quadratic Zeeman effect of Rydberg atoms in the framework of perturbation theory is dealt with and a special quasiclassical approximation scheme is applied. The Bohr-Sommerfeld quantization condition is given in terms of complete elliptic integrals. It is shown that part of the spectrum is doubly degenerate, the corresponding states are asymmetric with respect to the Coulomb centre and have a non-zero dipole moment; the rest of the spectrum is nondegenerate, the states are symmetric and their dipole-moment vanishes. The transition from the symmetric to the asymmetric region is similar to a phase transition and it gives an experimental possibility to distinguish between the two types of states. (author)

  17. Microwave-to-optical frequency conversion with a Rydberg atom coupled to a coplanar waveguide

    Science.gov (United States)

    Gard, Bryan; Jacobs, Kurt; McDermott, Robert; Saffman, Mark

    2017-04-01

    A primary candidate for converting quantum information from microwave to optical frequencies is the use of Rydberg states of a single atom trapped near a surface. The fact that the Rydberg states possess both large electric dipole moments and microwave transition frequencies allows them to interact with superconducting mesoscopic circuits. By considering a concrete example, that of a Cesium atom, and using numerical search methods to optimize the control protocols, we determine the fidelities and transmission rates that could be achievable with such a device. We show that while protocols that exploit the adiabatic STIRAP mechanism provide the best raw transfer fidelities, the fastest communication speeds can be obtained by using heralding, which allows one to remove the adiabatic constraint. Support from Oak Ridge Associated Universities.

  18. Use of fresh versus frozen or blast-frozen grapes for small-scale fermentation

    Directory of Open Access Journals (Sweden)

    Schmid F

    2011-10-01

    Full Text Available Frank Schmid, Vladimir Jiranek School of Agriculture, Food and Wine, The University of Adelaide; and Wine Innovation Cluster, The Waite Campus, Glen Osmond, South Australia, Australia Background: This paper firstly examines the validity of using laboratory-scale fermentations as a means of correlating winemaking outcomes with larger industrial scale fermentations. Secondly, conventional and blast-freezing of whole bunches were investigated for their relative suitability as methods of preservation as determined by the nature of the resulting wines. Methods: Red must fermentations were compared at the laboratory 80 kg scale, and the more industrially representative 500 kg pilot scale. Fermentation profiles and duration for both scales were found to be very similar. Whole bunches were either slow/conventionally frozen (−20°C, or quickly/blast-frozen (−25°C. Results: Wines made from frozen grapes compared well with the wine made from the fresh must. Color and chemical analyses of the wines revealed few differences. A duo-trio sensory evaluation showed that wine from blast-frozen grapes was more similar to the fresh wines than wines from conventional frozen grapes. Conclusion: The findings of this research suggest that whole-bunch blast-freezing of grapes is preferable to conventional freezing. Keywords: wine color, research winemaking, frozen grapes

  19. Rydberg atoms in circular polarization: Classical stabilization in optical frequency fields

    International Nuclear Information System (INIS)

    Chism, Will; Reichl, L.E.

    2002-01-01

    We investigate the classical dynamics of the Rydberg atom in circularly polarized laser fields, restricted to the two-dimensional plane of polarization. We use a Poincare surface of section to study nonlinear resonance structures for optical frequency driving fields. We demonstrate the existence and morphology of these structures as the laser intensity transitions from moderate to intense

  20. Asymptotics of Rydberg states for the hydrogen atom

    International Nuclear Information System (INIS)

    Thomas, L.E.

    1997-01-01

    The asymptotics of Rydberg states, i.e., highly excited bound states of the hydrogen atom Hamiltonian, and various expectations involving these states are investigated. We show that suitable linear combinations of these states, appropriately rescaled and regarded as functions either in momentum space or configuration space, are highly concentrated on classical momentum space or configuration space Kepler orbits respectively, for large quantum numbers. Expectations of momentum space or configuration space functions with respect to these states are related to time-averages of these functions over Kepler orbits. (orig.)

  1. The kicked Rydberg atom: Regular and stochastic motion

    International Nuclear Information System (INIS)

    Burgdoerfer, J.

    1988-01-01

    We have investigated the dynamics of a three-dimensional classical Rydberg atom driven by a sequence of pulses. Both the deterministic system with periodic pulses and the closely related ''noisy'' system with random pulses have been studied in parallel. The Lyapunov exponent is calculated as a function of pulse height and the angular momentum of the initial state. We find differences between noisy and deterministic perturbations to be most pronounced for small pulse heights. Low angular momentum orbits show enhanced diffusion in agreement with recent experimental data for ion-solid interaction. 22 refs., 6 figs

  2. Autoionizing Rydberg series in alkali atoms

    International Nuclear Information System (INIS)

    Kulov, M.A.; Ivanov, V.K.; Cherepkov, N.A.

    2004-01-01

    Full text: The results of many-body calculations of autoionizing resonance structure in neutral potassium, rubidium and cesium associated with the ns 2 np 6 (n+1)s → nsnp 6 (n+1)smp Rydberg excitations are presented. The numerical method based on the Many-Body Perturbation Theory takes into account the dynamic polarization and screening of electron-electron interaction by collective motion of the whole electronic system. The many-electron effects are shown to determine the resonance shapes. The numerically obtained cross section for photoionization of 3p electrons in neutral K in the vicinity of the 3s threshold is presented. The structure has the complex shape of 3s → mp resonances due to different behavior of electrons with the opposite spin projections

  3. Improving Rydberg Excitations within Time-Dependent Density Functional Theory with Generalized Gradient Approximations: The Exchange-Enhancement-for-Large-Gradient Scheme.

    Science.gov (United States)

    Li, Shaohong L; Truhlar, Donald G

    2015-07-14

    Time-dependent density functional theory (TDDFT) with conventional local and hybrid functionals such as the local and hybrid generalized gradient approximations (GGA) seriously underestimates the excitation energies of Rydberg states, which limits its usefulness for applications such as spectroscopy and photochemistry. We present here a scheme that modifies the exchange-enhancement factor to improve GGA functionals for Rydberg excitations within the TDDFT framework while retaining their accuracy for valence excitations and for the thermochemical energetics calculated by ground-state density functional theory. The scheme is applied to a popular hybrid GGA functional and tested on data sets of valence and Rydberg excitations and atomization energies, and the results are encouraging. The scheme is simple and flexible. It can be used to correct existing functionals, and it can also be used as a strategy for the development of new functionals.

  4. 21 CFR 146.137 - Frozen orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen orange juice. 146.137 Section 146.137 Food... Beverages § 146.137 Frozen orange juice. (a) Frozen orange juice is orange juice as defined in § 146.135, except that it is frozen. (b) The name of the food is “Frozen orange juice”. Such name may be preceded on...

  5. Toxigenic penicillia spoiling frozen chicken nuggets

    DEFF Research Database (Denmark)

    Wigmann, Evelin Francine; Saccomori, Fernanda; Bernardi, Angelica Olivier

    2015-01-01

    Frozen chicken nuggets are classified as pre-prepared frozen meals. These products are convenient to consumers as they are easy to prepare and allow for long storage by freezing. Over the years, spoilage of frozen food products caused by fungi has been a continual problem for the food industry...... of filamentous fungi involved in the spoilage of frozen chicken nuggets and determine their ability to produce mycotoxins under laboratorial conditions. A total of 7 samples of frozen chicken nuggets were analyzed by dilution plating in potato dextrose agar (PDA). These products had been returned by customers...

  6. The Eccentric Behavior of Nearly Frozen Orbits

    Science.gov (United States)

    Sweetser, Theodore H.; Vincent, Mark A.

    2013-01-01

    Frozen orbits are orbits which have only short-period changes in their mean eccentricity and argument of periapse, so that they basically keep a fixed orientation within their plane of motion. Nearly frozen orbits are those whose eccentricity and argument of periapse have values close to those of a frozen orbit. We call them "nearly" frozen because their eccentricity vector (a vector whose polar coordinates are eccentricity and argument of periapse) will stay within a bounded distance from the frozen orbit eccentricity vector, circulating around it over time. For highly inclined orbits around the Earth, this distance is effectively constant over time. Furthermore, frozen orbit eccentricity values are low enough that these orbits are essentially eccentric (i.e., off center) circles, so that nearly frozen orbits around Earth are bounded above and below by frozen orbits.

  7. Orthogonal flexible Rydberg aggregates

    Science.gov (United States)

    Leonhardt, K.; Wüster, S.; Rost, J. M.

    2016-02-01

    We study the link between atomic motion and exciton transport in flexible Rydberg aggregates, assemblies of highly excited light alkali-metal atoms, for which motion due to dipole-dipole interaction becomes relevant. In two one-dimensional atom chains crossing at a right angle adiabatic exciton transport is affected by a conical intersection of excitonic energy surfaces, which induces controllable nonadiabatic effects. A joint exciton-motion pulse that is initially governed by a single energy surface is coherently split into two modes after crossing the intersection. The modes induce strongly different atomic motion, leading to clear signatures of nonadiabatic effects in atomic density profiles. We have shown how this scenario can be exploited as an exciton switch, controlling direction and coherence properties of the joint pulse on the second of the chains [K. Leonhardt et al., Phys. Rev. Lett. 113, 223001 (2014), 10.1103/PhysRevLett.113.223001]. In this article we discuss the underlying complex dynamics in detail, characterize the switch, and derive our isotropic interaction model from a realistic anisotropic one with the addition of a magnetic bias field.

  8. Ultrafast non-adiabatic dynamics of methyl substituted ethylenes: The π3s Rydberg state

    Science.gov (United States)

    Wu, Guorong; Boguslavskiy, Andrey E.; Schalk, Oliver; Schuurman, Michael S.; Stolow, Albert

    2011-10-01

    Excited state unimolecular reactions of some polyenes exhibit localization of their dynamics at a single ethylenic double bond. Here we present studies of the fundamental photophysical processes in the ethylene unit itself. Combined femtosecond time-resolved photoelectron spectroscopy (TRPES) and ab initio quantum chemical calculations was applied to the study of excited state dynamics in cis-butene, trans-butene, trimethylethylene, and tetramethylethylene, following initial excitation to their respective π3s Rydberg states. The wavelength dependence of the π3s Rydberg state dynamics of tetramethylethylene was investigated in more detail. The π3s Rydberg to ππ* valence state decay rate varies greatly with substituent: the 1,2-di- and tri-methyl substituted ethylenes (cis-butene, trans-butene, and trimethylethylene) show an ultrafast decay (˜20 fs), whereas the fully methylated tetramethylethylene shows a decay rate of 2 to 4 orders of magnitude slower. These observations are rationalized in terms of topographical trends in the relevant potential energy surfaces, as found from ab initio calculations: (1) the barrier between the π3s state and the ππ* state increases with increasing methylation, and (2) the π3s/ππ* minimum energy conical intersection displaces monotonically away from the π3s Franck-Condon region with increasing methylation. The use of systematic methylation in combination with TRPES and ab initio computation is emerging as an important tool in discerning the excited state dynamics of unsaturated hydrocarbons.

  9. A universal representation of Rydberg spectral line shapes in plasmas

    International Nuclear Information System (INIS)

    Mosse, C.; Calisti, A.; Stamm, R.; Talin, B.; Bureyeva, L.; Lisitsa, V. S.

    2001-01-01

    A universal representation of Rydberg atom line shapes in plasmas is obtained. It bases on analytical formulas for intensity distribution in radiation transitions n→n' between highly excited atomic states with large values of principle quantum numbers n, n'>>1, Δn=n-n'<< n and the frequency fluctuation model (FFM) for account of ion thermal motion effects. The line shapes are presented in a universal manner as functions of plasma temperatures and densities

  10. Radio-over-fiber using an optical antenna based on Rydberg states of atoms

    Science.gov (United States)

    Deb, A. B.; Kjærgaard, N.

    2018-05-01

    We provide an experimental demonstration of a direct fiber-optic link for RF transmission ("radio-over-fiber") using a sensitive optical antenna based on a rubidium vapor cell. The scheme relies on measuring the transmission of laser light at an electromagnetically induced transparency resonance that involves highly excited Rydberg states. By dressing pairs of Rydberg states using microwave fields that act as local oscillators, we encoded RF signals in the optical frequency domain. The light carrying the information is linked via a virtually lossless optical fiber to a photodetector where the signal is retrieved. We demonstrate a signal bandwidth in excess of 1 MHz limited by the available coupling laser power and atomic optical density. Our sensitive, non-metallic and readily scalable optical antenna for microwaves allows extremely low-levels of optical power (˜1 μW) throughput in the fiber-optic link. It offers a promising future platform for emerging wireless network infrastructures.

  11. n l -> n' l' transition rates in electron and proton - Rydberg atom collision

    Science.gov (United States)

    Vrinceanu, Daniel

    2017-04-01

    Electrons and protons drive the recombination dynamics of highly excited Rydberg atoms in cold rarefied plasmas found in astrophysical conditions such as primordial recombination or star formation in H-II clouds. It has been recognized that collisions induce both energy and angular momentum transitions in Rydberg atoms, although in different proportions, depending on the initial state, temperature and the given species considered in the collision (electron or proton). Most studies focused on one collision type at a time, under the assumption that collision types are independent or their effects are not competing. The classical Monte-Carlo trajectory simulations presented in this work calculate the rates for both energy and angular momentum transfers and show their interdependence. For example, energy transfer with small angular momentum change are more efficient for target states with initial large angular momentum. The author acknowledges support received from the National Science Foundation through a Grant for the Center for Research on Complex Networks (HRD-1137732).

  12. Lamb shift of Rydberg atoms in a resonator

    International Nuclear Information System (INIS)

    Belov, A.A.; Lozovik, Yu.E.; Pokrovsky, V.L.

    1988-08-01

    The Lamb shift of a Rydberg atom in a cavity is shown to be enhanced with the resonance interaction of a virtual atomic transition and cavity modes. The dependence of the Lamb shift on quantum numbers and atomic number changes drastically. Shifting cavity walls and scanning the atomic beam one can vary the Lamb shift. The value of the Lamb shift in a cavity may exceed a typical magnitude of the fine structure energy. For a rough resonance tuning the Coulumb multiplet occurs to be strongly mixed and a novel classification is necessary. (author). 8 refs, 2 figs

  13. Mesoscopic Rydberg Gate Based on Electromagnetically Induced Transparency

    International Nuclear Information System (INIS)

    Mueller, M.; Lesanovsky, I.; Zoller, P.; Weimer, H.; Buechler, H. P.

    2009-01-01

    We demonstrate theoretically a parallelized C-NOT gate which allows us to entangle a mesoscopic ensemble of atoms with a single control atom in a single step, with high fidelity and on a microsecond time scale. Our scheme relies on the strong and long-ranged interaction between Rydberg atoms triggering electromagnetically induced transparency. By this we can robustly implement a conditional transfer of all ensemble atoms between two logical states, depending on the state of the control atom. We outline a many-body interferometer which allows a comparison of two many-body quantum states by performing a measurement of the control atom.

  14. Frozen shoulder and risk of cancer

    DEFF Research Database (Denmark)

    Pedersen, Alma B; Horváth-Puhó, Erzsébet; Ehrenstein, Vera

    2017-01-01

    BACKGROUND: Frozen shoulder might be a complication or a presenting symptom of cancer. We examined the risk of a cancer diagnosis after an incident diagnosis of frozen shoulder. METHODS: We used prospectively collected data from Danish registries to identify patients with frozen shoulder during 1...

  15. Adiabatic potential-energy curves of long-range Rydberg molecules: Two-electron R -matrix approach

    Czech Academy of Sciences Publication Activity Database

    Tarana, Michal; Čurík, Roman

    2016-01-01

    Roč. 93, č. 1 (2016), 012515 ISSN 0556-2791 R&D Projects: GA ČR(CZ) GP14-15989P Institutional support: RVO:61388955 Keywords : adiabatic-potential- energy curves * Rydberg molecules * theoretical chemistry Subject RIV: CF - Physical ; Theoretical Chemistry

  16. Adiabatic potential-energy curves of long-range Rydberg molecules: Two-electron R -matrix approach

    Czech Academy of Sciences Publication Activity Database

    Tarana, Michal; Čurík, Roman

    2016-01-01

    Roč. 93, č. 1 (2016), 012515 ISSN 0556-2791 R&D Projects: GA ČR(CZ) GP14-15989P Institutional support: RVO:61388955 Keywords : adiabatic-potential-energy curves * Rydberg molecules * theoretical chemistry Subject RIV: CF - Physical ; Theoretical Chemistry

  17. Term value/band-gap energy correlations for solid rare gas excitons

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Term value/ionization energy correlation algorithms have proven to be of considerable utility in the assignment of atomic and molecular Rydberg states. Many examples of empirical term value/ionization energy correlations are known for diverse classes of atoms and molecules. The purpose of this paper is to demonstrate that similar correlations are also obtained for excitons in rare gas solids

  18. 21 CFR 158.170 - Frozen peas.

    Science.gov (United States)

    2010-04-01

    ... CONSUMPTION FROZEN VEGETABLES Requirements for Specific Standardized Frozen Vegetables § 158.170 Frozen peas... two or more, of the following safe and suitable optional ingredients: (i) Natural and artificial... “early June” shall precede or follow the name in the case of smooth-skin or substantially smooth-skin...

  19. 21 CFR 160.150 - Frozen egg whites.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by freezing...

  20. 21 CFR 160.190 - Frozen egg yolks.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks that...

  1. Frozen heat: Global outlook on methane gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Beaudoin, Yannick; Solgaard, Anne

    2010-09-15

    The United Nations Environment Programme via its collaborating center in Norway, UNEP/GRID-Arendal, is undertaking an assessment of the state of the knowledge of methane gas hydrates. The Global Outlook on Methane Gas Hydrates seeks to bridge the gap between the science, research and development activities related to this potential large scale unconventional source of natural gas and the needs of decision makers and the general public to understand the underlying societal and environmental drivers and impacts. The Outlook aims to provide credible and unbiased information sourced from stakeholders representing the environment, government, industry and society.

  2. Frozen shoulder and the Big Five personality traits.

    Science.gov (United States)

    Debeer, Philippe; Franssens, Fien; Roosen, Isabelle; Dankaerts, Wim; Claes, Laurence

    2014-02-01

    In the past, several studies have suggested the existence of a "periarthritic personality" in patients with frozen shoulder. We conducted a study to determine differences in personality traits in patients with primary and secondary frozen shoulders. We prospectively evaluated 118 patients (84 women and 34 men; mean age, 53.8 years; SD 7.56) with a frozen shoulder. Of these patients, 48 had an idiopathic frozen shoulder and 70 had a secondary frozen shoulder. Personality traits were determined by the NEO Five-Factor Inventory (NEO-FFI) scale. This questionnaire measures the 5 major personality traits and is based on the norms determined in a neutral test situation for 2415 controls. Compared with healthy controls, no differences in personality traits were found in patients with primary and secondary frozen shoulder, except for Conscientiousness and Extraversion, for which patients with secondary frozen shoulder scored significantly higher than healthy controls. Patients with primary frozen shoulder scored significantly higher on Openness to Experience than did patients with secondary frozen shoulder; on the other 4 Big Five personality traits, no significant differences were found between patients with primary and secondary frozen shoulder. More specifically, patients with idiopathic frozen shoulder did not score higher on the trait Neuroticism as would be expected from previous publications. Our study results do not indicate that patients with an idiopathic frozen shoulder have a specific personality compared with healthy controls. Only a few differences were found in personality traits when the entire frozen shoulder group was compared with healthy controls and between patients with primary and secondary frozen shoulders. The results of this study suggest that these differences are not sufficient to speak about a specific "frozen shoulder personality." Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights

  3. Observation of electric quadrupole transitions to Rydberg nd states of ultracold rubidium atoms

    NARCIS (Netherlands)

    Tong, D.; Farooqi, S.M.; Kempen, van E.G.M.; Pavlovic, Z.; Stanojevic, J.; Coté, R.; Eyler, E.E.; Gould, P.L.

    2009-01-01

    We report the observation of dipole-forbidden, but quadrupole-allowed, one-photon transitions to high-Rydberg states in Rb. Using pulsed uv excitation of ultracold atoms in a magneto-optical trap, we excite 5s¿nd transitions over a range of principal quantum numbers n=27–59. Compared to

  4. Optical spectroscopy of high-L Rydberg states of argon

    International Nuclear Information System (INIS)

    Wright, L. E.; Snow, E. L.; Lundeen, S. R.; Sturrus, W. G.

    2007-01-01

    High-L fine structure patterns in n=9 and n=17 Rydberg levels of argon have been studied using a Doppler-tuned CO 2 laser and a fast beam of argon atoms. Analysis of the measured pattern using the polarization model yields the scalar dipole polarizability and quadrupole moment of the 2 P 3 at ∼sol∼ at 2 Ar + ion. The results are α S =6.83(8)a 0 3 and Q=-0.5177(15)ea 0 2 . Within the precision of this study, no vector component of the structure was observed

  5. Comparison of chemical, microbiological and histological changes in fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Peter Popelka

    2014-01-01

    Full Text Available The final quality of fish meat depends on the chemical and microbiological quality of fish at the time of freezing as well as on other factors including storage temperature and freezing rate. Analysis of chemical composition (water, protein and fat content, expressible drip, total volatile nitrogen levels, microbiological analyses (total viable counts, Enterobacteriaceae, psychrotrophic bacteria and histological examinations on dorsal skeletal muscles were carried out to distinguish fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss. Significantly higher expressible drip and total volatile base nitrogen concentrations (P Enterobacteriaceae and psychrotrophic bacteria were determined in double frozen trout. The light microscopy of fresh trout muscles did not show any microstructural changes, whereas deformations of muscle fibres and optically empty areas were found in frozen trout. Remarkable defects of the muscle structure in double frozen trout were demonstrated and total disruption of muscle fibres was found. The freezing of trout resulted in various structural changes in the dorsal skeletal musculature. This is a first study comparing changes in fresh, frozen and repeatedly frozen trout. Chemical, microbiological and subsequent histological examinations can be used for revealing the foul practices confusing the consumer with offering thawed fish instead of fresh cooled fish.

  6. Comparative biomechanical study between fresh frozen bone and fresh frozen pasteurized bone process

    International Nuclear Information System (INIS)

    Ferdiansyah Abdurrahman

    1999-01-01

    To observe the biomechanical properties difference between fresh frozen bone and fresh frozen pasteurized bone process Thirty eight femurs bones taken from 6 years old primate.(macaca fascicularis) from Primate Nursery Center LIPI Bogor, 20 bones were 6 cm cut for bending test and 18 remains were 3 cm cut for compression test. All bones were frozen and then divided into two groups for each biomechanical study. First group (I 0 bones for bending test and 9 bones for compression test) were undergone fresh frozen procession only. The second group with the same amount was undergone fresh frozen and pasteurized on 60 degree C for three hours. Bending test was done until the bones were broken on control group and pasteurized group and the result was compared, the same procedure was done for compression test. The study was done in room temperature. The biomechanical test result was analyzed by two independent T tests. The bending test control group has ( mean 0.097 N / mm sup 2 (SD = 0.007) and the pasteurized group ( mean 0. I 0 1 N / mm sup 2 (SD = 0.0 1 3), there was no significant difference (p 0.399). The compression test control group has ( = mean 0.71 N / mm sup 2 (SD=0.128)where as the pasteurized group has(mean 0.50N/mm sup 2 (SD=0.111),there was significant difference (p =0.004) From the result biomechanical study on bending test, there was no significant difference of bone strength, whereas on compression test the fresh frozen with pasteurized bone group is 125% stronger than control group. The result of this study will be very useful for reconstruction bone allograft

  7. Rydberg-atom based radio-frequency electrometry using frequency modulation spectroscopy in room temperature vapor cells.

    Science.gov (United States)

    Kumar, Santosh; Fan, Haoquan; Kübler, Harald; Jahangiri, Akbar J; Shaffer, James P

    2017-04-17

    Rydberg atom-based electrometry enables traceable electric field measurements with high sensitivity over a large frequency range, from gigahertz to terahertz. Such measurements are particularly useful for the calibration of radio frequency and terahertz devices, as well as other applications like near field imaging of electric fields. We utilize frequency modulated spectroscopy with active control of residual amplitude modulation to improve the signal to noise ratio of the optical readout of Rydberg atom-based radio frequency electrometry. Matched filtering of the signal is also implemented. Although we have reached similarly, high sensitivity with other read-out methods, frequency modulated spectroscopy is advantageous because it is well-suited for building a compact, portable sensor. In the current experiment, ∼3 µV cm-1 Hz-1/2 sensitivity is achieved and is found to be photon shot noise limited.

  8. The search For Closed Orbits Of General Rydberg Atoms in External Fields And Their Classification

    International Nuclear Information System (INIS)

    Carboni, R.

    1997-01-01

    A program of high precision that find closed orbits for the classical motion of the electron of general Rydberg atoms in crossed magnetic and electric fields is explained. Investigations of the influence of the ionic core on the electronic trajectories using a phenomenological model potential were done. Additional closed orbits that are not present in hydrogen atoms and that seem to be composed of hydrogenic orbits were found. The stability and formation of orbits are explained. Using the generalized closed-orbit theory, the scaled recurrence spectra for rubidium Rydberg atoms were calculated. The results are in good agreement with reported experiments. Two important features of the expectra can be explained by classical core scattering: The additional non-hydrogenic resonances associated to composite orbits and the vanishing of hydrogenic resonances related to closed or whose trajectories approach the core. (Author) [es

  9. Molecular physics. Production of trilobite Rydberg molecule dimers with kilo-Debye permanent electric dipole moments.

    Science.gov (United States)

    Booth, D; Rittenhouse, S T; Yang, J; Sadeghpour, H R; Shaffer, J P

    2015-04-03

    Permanent electric dipole moments are important for understanding symmetry breaking in molecular physics, control of chemical reactions, and realization of strongly correlated many-body quantum systems. However, large molecular permanent electric dipole moments are challenging to realize experimentally. We report the observation of ultralong-range Rydberg molecules with bond lengths of ~100 nanometers and kilo-Debye permanent electric dipole moments that form when an ultracold ground-state cesium (Cs) atom becomes bound within the electronic cloud of an extended Cs electronic orbit. The electronic character of this hybrid class of "trilobite" molecules is dominated by degenerate Rydberg manifolds, making them difficult to produce by conventional photoassociation. We used detailed coupled-channel calculations to reproduce their properties quantitatively. Our findings may lead to progress in ultracold chemistry and strongly correlated many-body physics. Copyright © 2015, American Association for the Advancement of Science.

  10. Strongly perturbed Rydberg series originating from KrII 4p45s ionic states

    International Nuclear Information System (INIS)

    Petrov, I.D.; Demekhin, Ph.V.; Lagutin, B.M.; Sukhorukov, V.L.; Kammer, S.; Mickat, S.; Schartner, K.-H.; Ehresmann, A.; Klumpp, S.; Werner, L.; Schmoranzer, H.

    2005-01-01

    Photoionization cross-sections for the 4p 4 ( 3 P) 5s 4 P 5/2,3/2,1/2 satellites and 4s, 4p main levels of Kr II in the exciting-photon energy range between 28.48 and 28.70-bar eV with extremely narrow bandwidth (1.7-bar meV at 28.55-bar eV) of the monochromatized synchrotron radiation were measured utilizing the photon-induced fluorescence spectroscopy. The observed resonances were assigned to the 4p 4 5s( 4 P 1/2 )n p and 4p 4 5s( 2 P 3/2 )n p Rydberg series on the basis of calculations performed with taking into account core relaxation and interaction between many resonances and many continua. The calculation shows that the resonance structure in the photoionization channels exists due to 4p 4 ( 1 D) 5s 2 D 5/2 6p 3/2 promoter state which also strongly perturbs the above Rydberg series.

  11. Oscillatory behaviour of Rydberg state total cross sections in the collisions Ne+-He and He+-Ne

    International Nuclear Information System (INIS)

    Andresen, B.; Jensen, K.; Veje, E.

    1976-01-01

    The Ne + -He and He + -Ne collisions have been studied by means of optical spectrometry in the projectile energy range 10-150 keV. Very similar and regular oscillations in the Rydberg state total cross sections are found for HeI in both collisions and for singlet as well as triplet excitation. These oscillations are well described by the Rosenthal model. The HeI 4d sup(1,3)D states display two superimposed oscillations for center-of-mass collision energies above 6.4 keV. This is interpreted as the opening of a third exit channel, believed to be the HeI 4f sup(1,3)F. No, or very little structure is found in the Rydberg state total cross sections for HeII, NeI, NeII and NeIII levels. (Auth.)

  12. Project to develop and demonstrate methods to eliminate frozen coal handling problems. Status report I

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-15

    For too many years, problems associated with frozen coal have plagued the companies who mine it, the companies who handle it in transit and the utilities and other industrial concerns that finally burn it. But never before has the magnitude of the frozen coal problem been as great as it is today because of two primary factors, i.e. (1) the majority of coal currently transported and used has been ground to a very fine mesh that absorbs water readily, thus providing more surface area for freezing, and (2) the substantially increased importance of coal, indeed, the now critical necessity for more coal to be used in displacing dangerously uncertain foreign oil supplies that currently account for 50 percent of our daily domestic oil consumption. Frozen coal problems can and do have a devastating effect upon the ability to provide energy from coal during harsh winter months when it is not needed. The majority of these problems have been involved with removing frozen coal from rail cars. To allay the problem, numerous techniques have been tried, all with some measure of success. As an example, certain chemicals have been sprayed on the coal; another common treatment has been widespread use of thaw sheds, which, whether electrically or gas-fired, are all energy intensive, time consuming, hard on rail equipment and expensive to operate over long periods of time. From sledge hammers and crow bars to gas-fired jets and electric thaw sheds, available mechanical de-icing methods often damage coal handling equipment, are time consuming and, therefore, very expensive when demurrage losses must be added to significant investment and/or operating costs.

  13. Effect of Oven Types on the Characteristics of Biscuits Made from Refrigerated and Frozen Doughs

    Directory of Open Access Journals (Sweden)

    Ismail Sait Dogan

    2006-01-01

    Full Text Available Characteristics of sugar snap and chocolate chip cookies, and hazelnut biscuits made from refrigerated and frozen dough were studied. Doughs were stored at 4 °C for 6 weeks and at –18 °C for 6 months, respectively. Physical characteristics of the biscuit samples such as spread, baking loss, surface colour and density were determined. Dough colour was not affected by storage time and temperatures. Biscuit characteristics did not change significantly during storage. Spread ratio was significantly lower for the biscuits baked in the gas oven than for the biscuits baked in the electric oven. Biscuit dough can be refrigerated for 6 weeks, and frozen for 6 months. Results also suggest that unique quality differences exist between the two ovens. For sugar snap cookies and hazelnut biscuits the electric oven without air circulation was better, while for chocolate chip cookies gas oven with air circulation was more suitable.

  14. Decay, excitation, and ionization of lithium Rydberg states by blackbody radiation

    Science.gov (United States)

    Ovsiannikov, V. D.; Glukhov, I. L.

    2010-09-01

    Details of interaction between the blackbody radiation and neutral lithium atoms were studied in the temperature ranges T = 100-2000 K. The rates of thermally induced decays, excitations and ionization were calculated for S-, P- and D-series of Rydberg states in the Fues' model potential approach. The quantitative regularities for the states of the maximal rates of blackbody-radiation-induced processes were determined. Approximation formulas were proposed for analytical representation of the depopulation rates.

  15. Investigation of the Impact of Different Terms in the Second Order Hamiltonian on Excitation Energies of Valence and Rydberg States.

    Science.gov (United States)

    Tajti, Attila; Szalay, Péter G

    2016-11-08

    Describing electronically excited states of molecules accurately poses a challenging problem for theoretical methods. Popular second order techniques like Linear Response CC2 (CC2-LR), Partitioned Equation-of-Motion MBPT(2) (P-EOM-MBPT(2)), or Equation-of-Motion CCSD(2) (EOM-CCSD(2)) often produce results that are controversial and are ill-balanced with their accuracy on valence and Rydberg type states. In this study, we connect the theory of these methods and, to investigate the origin of their different behavior, establish a series of intermediate variants. The accuracy of these on excitation energies of singlet valence and Rydberg electronic states is benchmarked on a large sample against high-accuracy Linear Response CC3 references. The results reveal the role of individual terms of the second order similarity transformed Hamiltonian, and the reason for the bad performance of CC2-LR in the description of Rydberg states. We also clarify the importance of the T̂ 1 transformation employed in the CC2 procedure, which is found to be very small for vertical excitation energies.

  16. Strongly perturbed Rydberg series originating from Kr II 4p45s ionic states

    International Nuclear Information System (INIS)

    Petrov, I.D.; Demekhin, P.V.; Lagutin, B.M.; Sukhorukov, V.L.; Kammer, S.; Mickat, S.; Schartner, K.-H.; Ehresmann, A.; Klumpp, S.; Werner, L.; Schmoranzer, H.

    2004-01-01

    Full text:Dispersed fluorescence excitation spectra for KrII fluorescence transitions to the 4p 4 5s 4 P 3/2 , 5/2 states were observed after excitation out of the KrI ground state with photons of energies between 28.4 eV and 28.7 eV and very narrow exciting-photon bandwidth of 1.7 meV. With this energy resolution it was possible to observe Rydberg series of doubly excited atomic states. The observed series were assigned to the states 4p 4 5s( 4 P 1/2 )np and 4p 4 5s( 2 P 3/2 )np ,based on calculations performed within theory taking into account interaction between many resonances and many continua. Calculated and measured cross sections are compared for the 4p - level (upper panel, ion yield) and for the 4p 4 5s 4 P 5/2 level (lower panel). An analysis of the computed photoionization (PI) cross sections shows that high - n members of Rydberg series are strongly perturbed by interaction with low - n ones of other series. In particular, the series shown are well pronounced because they borrow intensity from the low - n 4p 4 5s( 2 D 5/2 )6p 3/2 doublyexcited state. The above Rydberg series are predicted to be observable in photoelectron experiments, too. FIG. 1 shows, e.g., that members of the 4p 4 5s( 2 P 3/2 )np series starting from n 14 could also be observed in the 4p 4 5s 4P 1/2 observer channel at low photoelectron energies

  17. Resonance-enhanced multiphoton ionization photoelectron spectroscopy of even-parity autoionizing Rydberg states of atomic sulphur

    NARCIS (Netherlands)

    Woutersen, S.; de Milan, J.B.; de Lange, C.A.; Buma, W.J.

    1997-01-01

    Several previously unobserved Rydberg states of the sulphur atom above the lowest ionization threshold are identified and assigned using (2 + 1) resonance-enhanced multiphoton-ionization photoelectron spectroscopy. All states were accessed by two-photon transitions from either the 3P ground or the

  18. ARC: An open-source library for calculating properties of alkali Rydberg atoms

    Science.gov (United States)

    Šibalić, N.; Pritchard, J. D.; Adams, C. S.; Weatherill, K. J.

    2017-11-01

    We present an object-oriented Python library for the computation of properties of highly-excited Rydberg states of alkali atoms. These include single-body effects such as dipole matrix elements, excited-state lifetimes (radiative and black-body limited) and Stark maps of atoms in external electric fields, as well as two-atom interaction potentials accounting for dipole and quadrupole coupling effects valid at both long and short range for arbitrary placement of the atomic dipoles. The package is cross-referenced to precise measurements of atomic energy levels and features extensive documentation to facilitate rapid upgrade or expansion by users. This library has direct application in the field of quantum information and quantum optics which exploit the strong Rydberg dipolar interactions for two-qubit gates, robust atom-light interfaces and simulating quantum many-body physics, as well as the field of metrology using Rydberg atoms as precise microwave electrometers. Program Files doi:http://dx.doi.org/10.17632/hm5n8w628c.1 Licensing provisions: BSD-3-Clause Programming language: Python 2.7 or 3.5, with C extension External Routines: NumPy [1], SciPy [1], Matplotlib [2] Nature of problem: Calculating atomic properties of alkali atoms including lifetimes, energies, Stark shifts and dipole-dipole interaction strengths using matrix elements evaluated from radial wavefunctions. Solution method: Numerical integration of radial Schrödinger equation to obtain atomic wavefunctions, which are then used to evaluate dipole matrix elements. Properties are calculated using second order perturbation theory or exact diagonalisation of the interaction Hamiltonian, yielding results valid even at large external fields or small interatomic separation. Restrictions: External electric field fixed to be parallel to quantisation axis. Supplementary material: Detailed documentation (.html), and Jupyter notebook with examples and benchmarking runs (.html and .ipynb). [1] T.E. Oliphant

  19. Fertility test of frozen boar semen.

    Science.gov (United States)

    Osinowa, O; Salamon, S

    1976-10-01

    The fertility results of two experiments are presented. In experiment 1, the semen was frozen in tris-fructose-EDTA or BF3 diluents at 0-25 X 10(9)/ml sperm concentration and extended after thawing with either seminal plasma (SP) or the freezing medium (FM) containing no cryoprotective agent. In the second experiment the semen was glycerolated by two methods, frozen at 1-0 X 10(9)/ml sperm concentration, and extended wtih FM before insemination. Fertility after double insemination within one oestrus with semen frozen in tris-fructose-EDTA or BF3 diluents varied depending on the medium used for extension of thawed semen. The farrowing rates for semen frozen in the former diluent with FM and SP post-thawing media were 4/8 and 1/8 respectively, and for semen frozen BF3 diluent with FM and SP post-thawing extenders 1/8 and 5/8. The mean farrowing for the 32 animals inseminasted was 34-4%. Pregnancies for semen frozen in tris-fructose-EDTA and glycerolated at 30 or 5 degrees C were 5/12 and 4/12 respectively, and for single and double inseminations 6/12 and 3/12 respectively. Of 24 animals inseminated 37-5% farrowed.

  20. Observation of the Stark effect in υ+ = 0 Rydberg states of NO: a comparison between predissociating and bound states

    International Nuclear Information System (INIS)

    Jones, N J A; Minns, R S; Patel, R; Fielding, H H

    2008-01-01

    The Stark spectra of Rydberg states of NO below the υ + = 0 ionization limit, with principal quantum numbers n = 25-30, have been investigated in the presence of dc electric fields in the range 0-150 V cm -1 . The Stark states were accessed by two-colour, double-resonance excitation via the υ' = 0, N' = 0 rovibrational state of the A 2 Σ + state. The N( 2 D) atoms produced by predissociation were measured by (2 + 1) resonance-enhanced multiphoton ionization, and compared with pulsed-field ionization spectra of the bound Rydberg state population (Patel et al 2007 J. Phys. B: At. Mol. Opt. Phys. 40 1369)

  1. Ionization of xenon Rydberg atoms at Si(1 0 0) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Dunham, H.R. [Department of Physics and Astronomy, Rice University MS-61, 6100 Main Street, Houston, TX 77005-1892 (United States); Wethekam, S. [Institut fuer Physik der Humboldt-Universitaet zu Berlin, Newtonstra. 15, D-12489, Berlin (Germany); Lancaster, J.C. [Department of Physics and Astronomy, Rice University MS-61, 6100 Main Street, Houston, TX 77005-1892 (United States); Dunning, F.B. [Department of Physics and Astronomy, Rice University MS-61, 6100 Main Street, Houston, TX 77005-1892 (United States)]. E-mail: fbd@rice.edu

    2007-03-15

    The ionization of xenon Rydberg atoms excited to the lowest states in the n = 17 and n = 20 Stark manifolds at Si(1 0 0) surfaces is investigated. It is shown that, under appropriate conditions, a sizable fraction of the incident atoms can be detected as ions. Although the onset in the ion signal is perturbed by stray fields present at the surface, the data are consistent with ionization rates similar to those measured earlier at metal surfaces.

  2. Interaction of Rydberg atoms in circular states with the alkaline-earth Ca(4s{sup 2}) and Sr(5s{sup 2}) atoms

    Energy Technology Data Exchange (ETDEWEB)

    Mironchuk, E. S.; Narits, A. A.; Lebedev, V. S., E-mail: vlebedev@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2015-11-15

    The resonant mechanism of interaction of alkaline-earth atoms having a low electron affinity to Rydberg atoms in circular (l = vertical bar m vertical bar = n–1) and near-circular states has been studied. To describe the dynamics of resonant processes accompanied by nonadiabatic transitions between ionic and Rydberg covalent terms of a quasimolecule, an approach based on the integration of coupled equations for the probability amplitudes has been developed taking into account the possibility of the decay of an anion in the Coulomb field of the positive ionic core of a highly excited atom. The approach involves the specific features of the problem associated with the structure of the wavefunction of a Rydberg electron in states with high orbital angular momenta l ∼ n–1. This approach provides a much more accurate description of the dynamics of electronic transitions at collisions between atoms than that within the modified semiclassical Landau–Zener model. In addition, this approach makes it possible to effectively take into account many channels of the problem. The cross sections for resonant quenching of Rydberg states of the Li(nlm) atom with given principal n, orbital l = n–1, and magnetic m quantum numbers at thermal collisions with the Ca(4s{sup 2}) and Sr(5s{sup 2}) atoms have been calculated. The dependences of the results on n, m, and angle α between the relative velocity of the atoms and the normal to the plane of the orbit of the Rydberg electron have been obtained. The influence of orientational effects on the efficiency of the collisional destruction of circular and near-circular states has been studied. The results indicate a higher stability of such states to their perturbations by neutral particles as compared to usually studied nl states with low values of l (l ≪ n)

  3. Properties of Fr-like Th^3+ from microwave spectroscopy of high-L Rydberg states of Th^2+

    Science.gov (United States)

    Keele, Julie; Smith, Chris; Woods, Shannon; Lundeen, Stephen; Fehrenbach, Charles

    2012-06-01

    Spectroscopy of high-L n= 28 Rydberg levels of Th^2+ was recently reported using the optical RESIS method [1]. Because the ground state of Fr-like Th^3+ is a ^2F5/2 level, each (n,L) Rydberg level of Th^2+ is split into six eigenstates whose relative positions are determined by long-range e-Th^3+ interactions. Measurements of those positions can be used to determine the Th^3+ properties that control those interactions, such as polarizabilities and permanent moments. We report a much improved study of n=28 levels with 9 Hanni, Shannon L. Woods, S.R. Lundeen, and C.W. Fehrenbach, Phys. Rev. A 83, 062501 (2011)[0pt] [2] U.I. Safronova, W.R. Johnson, and M.S. Safronova, Phys. Rev. A 74, 042511 (2006)

  4. Photoionization microscopy of Rydberg hydrogen atom in a non-uniform electrical field

    International Nuclear Information System (INIS)

    Cheng Shao-Hao; Wang De-Hua; Chen Zhao-Hang; Chen Qiang

    2016-01-01

    In this paper, we investigate the photoionization microscopy of the Rydberg hydrogen atom in a gradient electric field for the first time. The observed oscillatory patterns in the photoionization microscopy are explained within the framework of the semiclassical theory, which can be considered as a manifestation of interference between various electron trajectories arriving at a given point on the detector plane. In contrast with the photoionization microscopy in the uniform electric field, the trajectories of the ionized electron in the gradient electric field will become chaotic. An infinite set of different electron trajectories can arrive at a given point on the detector plane, which makes the interference pattern of the electron probability density distribution extremely complicated. Our calculation results suggest that the oscillatory pattern in the electron probability density distribution depends sensitively on the electric field gradient, the scaled energy and the position of the detector plane. Through our research, we predict that the interference pattern in the electron probability density distribution can be observed in an actual photoionization microscopy experiment once the external electric field strength and the position of the electron detector plane are reasonable. This study provides some references for the future experimental research on the photoionization microscopy of the Rydberg atom in the non-uniform external fields. (paper)

  5. A laser system for the spectroscopy on highly charged ions, tellurium molecules, and Rydberg states of rubidium atoms; Ein Lasersystem zur Spektroskopie von hochgeladenen Ionen, Tellurmolekuelen und Rubidium-Rydberg-Zustaenden

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, Sebastian

    2014-08-15

    Optical measuring methods allow the detection and identification of the atomic structure with extraordinary precision. Deviations to theoretical predictions can indicate unknown physical effects. Therefore, precise measurements on the atomic structure continue to be of large relevance. In this work, a laser system for precision spectroscopy on Bismuth ({sup 209}Bi{sup 82+}), Tellurium ({sup 130}Te{sub 2}) and Rydberg states of Rubidium ({sup 85}Rb) has been built and characterized. Spectroscopic measurements on Tellurium and Rubidium have been achieved with this setup. The system consists of a two-stage frequency doubled diode laser, stabilized via a cavity and an RF-offsetlock to arbitrary wavelengths with absolute high stability. The setup of the laser system will be presented and the systematic error caused by the refractive index of air inside the transfer cavity will be discussed. A stability of better then 6.14 MHz at 244 nm is obtained for planned experiments on the ground state hyperfine splitting of {sup 209}Bi{sup 82+}. This will allow an increase in precision of more then four orders of magnitude for this measurement. Further increase in precision can be achieved by using an evacuated cavity. The obtained stability is measured by comparison of the laser frequency to absorption lines of Tellurium ({sup 130}Te{sub 2}). Eight reference lines, known from literature, spanning the region from 613720.717 GHz to 616803.545 GHz have been measured. The frequency measurements of three lines, coinciding with the emission spectrum of an argon-ion-laser, show deviations with respect to the published frequencies. Further inconsistencies in literature are cleared. Part of this work is also the precise measurement of 843 Doppler-free {sup 130}Te{sub 2} reference lines spanning the frequency range from 613881.150 GHz to 616614.258 GHz at a precision of better then 4 MHz for most lines. Additionally, measurements on electromagnetically induced transparency (EIT) using

  6. Self-excitation of Rydberg atoms at a metal surface

    DEFF Research Database (Denmark)

    Bordo, Vladimir

    2017-01-01

    The novel effect of self-excitation of an atomic beam propagating above a metal surface is predicted and a theory is developed. Its underlying mechanism is positive feedback provided by the reflective surface for the atomic polarization. Under certain conditions the atomic beam flying in the near...... field of the metal surface acts as an active device that supports sustained atomic dipole oscillations, which generate, in their turn, an electromagnetic field. This phenomenon does not exploit stimulated emission and therefore does not require population inversion in atoms. An experiment with Rydberg...... atoms in which this effect should be most pronounced is proposed and the necessary estimates are given....

  7. Short-term Clinical Results of Manipulation Under Ultrasound-Guided Brachial Plexus Block in Patients with Idiopathic Frozen Shoulder and Diabetic Secondary Frozen Shoulder.

    Science.gov (United States)

    Ando, Akira; Hamada, Junichiro; Hagiwara, Yoshihiro; Sekiguchi, Takuya; Koide, Masashi; Itoi, Eiji

    2018-01-01

    This study examined the effectiveness of manipulation under ultrasound-guided brachial plexus block in patients with recalcitrant idiopathic frozen shoulder and diabetic secondary frozen shoulder (diabetic frozen shoulder). Forty-four idiopathic frozen shoulders and 10 diabetic frozen shoulders with failed conservative treatment for at least 3 months were included in this study. The manipulation was performed under ultrasound-guided brachial plexus block and visual analogue scale, range of motion, and Constant scores were measured before manipulation and at the last follow-up examination. No major complications were observed during the procedure. Sufficient improvement was not obtained in two patients during the procedure and to avoid complications, the procedure was discontinued and subsequently arthroscopic capsular release was performed. Visual analogue scale, range of motion towards all directions, and Constant scores were significantly improved after the manipulation in both the idiopathic frozen shoulder and diabetic frozen shoulder groups, however the diabetic group showed inferior results compared with those of the idiopathic group. This manipulation was effective and shortened the duration of symptoms in most of the idiopathic and diabetic frozen shoulders without major complications during the procedure. Diabetic frozen shoulder showed inferior clinical results and difficulty in recovery in range of motion, which indicated that diabetic frozen shoulder should be discussed as a different entity.

  8. Nonspreading Wave Packets for Rydberg Electrons in Rotating Molecules with Electric Dipole Moments

    International Nuclear Information System (INIS)

    Bialynicki-Birula, I.; Bialynicka-Birula, Z.

    1996-01-01

    Nonspreading wave packets for Rydberg electrons are predicted in rotating molecules with electric dipole moments. We have named them the Trojan wave packets since their stability is due to the same mechanism that governs the motion of the Trojan asteroids in the Sun-Jupiter system. Unlike all previously predicted Trojan wave packets in atoms, molecular Trojan states do not require external fields for their existence

  9. Ramsey interferometry of Rydberg ensembles inside microwave cavities

    Science.gov (United States)

    Sommer, Christian; Genes, Claudiu

    2018-06-01

    We study ensembles of Rydberg atoms in a confined electromagnetic environment such as is provided by a microwave cavity. The competition between standard free space Ising type and cavity-mediated interactions leads to the emergence of different regimes where the particle‑particle couplings range from the typical van der Waals r ‑6 behavior to r ‑3 and to r-independence. We apply a Ramsey spectroscopic technique to map the two-body interactions into a characteristic signal such as intensity and contrast decay curves. As opposed to previous treatments requiring high-densities for considerable contrast and phase decay (Takei et al 2016 Nat. Comms. 7 13449; Sommer et al 2016 Phys. Rev. A 94 053607), the cavity scenario can exhibit similar behavior at much lower densities.

  10. Observation of Rydberg transitions from the inner valence shell of ethane

    International Nuclear Information System (INIS)

    Dillon, M.A.; Tanaka, H.; Spence, D.

    1987-01-01

    The electron impact spectrum of ethane has been examined in a region that includes ionization out of the inner valence shell. One diffuse structure and a progression of ten vibrational bands have been found in a 4 eV range below and to some degree overlapping the 2 A 2 /sub u/ ion threshold. Evidence indicates that the observed transitions belong to the symmetry forbidden Rydberg series (2a 2 /sub u/) 2 →(2a 2 /sub u/, npσ or npπ)

  11. Gas hydrate in nature

    Science.gov (United States)

    Ruppel, Carolyn D.

    2018-01-17

    Gas hydrate is a naturally occurring, ice-like substance that forms when water and gas combine under high pressure and at moderate temperatures. Methane is the most common gas present in gas hydrate, although other gases may also be included in hydrate structures, particularly in areas close to conventional oil and gas reservoirs. Gas hydrate is widespread in ocean-bottom sediments at water depths greater than 300–500 meters (m; 984–1,640 feet [ft]) and is also present in areas with permanently frozen ground (permafrost). Several countries are evaluating gas hydrate as a possible energy resource in deepwater or permafrost settings. Gas hydrate is also under investigation to determine how environmental change may affect these deposits.

  12. 48 CFR 852.246-72 - Frozen processed foods.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Frozen processed foods. 852.246-72 Section 852.246-72 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Frozen processed foods. As prescribed in 846.302-72, insert the following clause: Frozen Processed Foods...

  13. 48 CFR 846.302-72 - Frozen processed foods.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Frozen processed foods... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Clauses 846.302-72 Frozen processed foods. The contracting officer shall insert the clause at 852.246-72, Frozen processed foods, in solicitations and contracts for...

  14. Excited states of ethylene interpreted in terms of perturbed Rydberg series

    International Nuclear Information System (INIS)

    Yamamoto, Shigeyoshi; Tatewaki, Hiroshi

    2003-01-01

    We have investigated the excited states of the ethylene molecule by the multireference configuration interaction (MRCI) method. In particular, the nature of the V state (1 1 B 1u π→π*) was interpreted in terms of perturbed Rydberg series. To clarify the role of the perturbers, we use pseudo-restricted Hartree-Fock natural orbitals (PRHFNO), which would be the most suitable molecular orbital set to describe Rydberg series. It is well known that the expectation value of x 2 for the V state is reduced from 44a 0 2 (RHF) to around 17a 0 2 by considering electron correlation effects, where x is the direction out of the molecular plane. In the present study, a reasonable 2 > value was obtained from small multireference configuration interaction with single excitations (MRCIS), where the π→π* configurations and a few perturbers were assigned as the reference configurations. The major perturbers were found to be five configurations represented by 3a g → 3b 1u , 1b 3g → 3b 2u , 2b 1u → 4a g , 2a g → 3b 1u , and 1b 2u → 2b 3g with respect to the ground state configuration. The V state can therefore be described as a scattering process of the π→π* state by these perturbers. Other low-lying excited states are also investigated by the MRCI method

  15. The importance of Rydberg orbitals in dissociative ionization of small hydrocarbon molecules in intense laser fields.

    Science.gov (United States)

    Jochim, Bethany; Siemering, R; Zohrabi, M; Voznyuk, O; Mahowald, J B; Schmitz, D G; Betsch, K J; Berry, Ben; Severt, T; Kling, Nora G; Burwitz, T G; Carnes, K D; Kling, M F; Ben-Itzhak, I; Wells, E; de Vivie-Riedle, R

    2017-06-30

    Much of our intuition about strong-field processes is built upon studies of diatomic molecules, which typically have electronic states that are relatively well separated in energy. In polyatomic molecules, however, the electronic states are closer together, leading to more complex interactions. A combined experimental and theoretical investigation of strong-field ionization followed by hydrogen elimination in the hydrocarbon series C 2 D 2 , C 2 D 4 and C 2 D 6 reveals that the photofragment angular distributions can only be understood when the field-dressed orbitals rather than the field-free orbitals are considered. Our measured angular distributions and intensity dependence show that these field-dressed orbitals can have strong Rydberg character for certain orientations of the molecule relative to the laser polarization and that they may contribute significantly to the hydrogen elimination dissociative ionization yield. These findings suggest that Rydberg contributions to field-dressed orbitals should be routinely considered when studying polyatomic molecules in intense laser fields.

  16. The Rydberg constant and proton size from atomic hydrogen

    Science.gov (United States)

    Beyer, Axel; Maisenbacher, Lothar; Matveev, Arthur; Pohl, Randolf; Khabarova, Ksenia; Grinin, Alexey; Lamour, Tobias; Yost, Dylan C.; Hänsch, Theodor W.; Kolachevsky, Nikolai; Udem, Thomas

    2017-10-01

    At the core of the “proton radius puzzle” is a four-standard deviation discrepancy between the proton root-mean-square charge radii (rp) determined from the regular hydrogen (H) and the muonic hydrogen (µp) atoms. Using a cryogenic beam of H atoms, we measured the 2S-4P transition frequency in H, yielding the values of the Rydberg constant R∞ = 10973731.568076(96) per meterand rp = 0.8335(95) femtometer. Our rp value is 3.3 combined standard deviations smaller than the previous H world data, but in good agreement with the µp value. We motivate an asymmetric fit function, which eliminates line shifts from quantum interference of neighboring atomic resonances.

  17. Microwave spectroscopy of high-L Rydberg states of nickel

    Science.gov (United States)

    Lindsay, Mark D.; Keele, Julie A.; Woods, Shannon L.; Lundeen, Stephen R.

    2010-03-01

    High-L non-penetrating Rydberg levels of nickel display a fine structure pattern consisting of six levels for each value of L. This pattern was studied recently with the optical RESIS technique, determining initial values of the quadrupole moment and polarizabilities of the ^2D5/2 ground state of Ni^+ [1]. Measurements are now in progress using the microwave RESIS technique [2], which promises much more precise measurements of the fine structure and of the related core properties, including the permanent hexadecapole moment.[4pt] [1] Julie A. Keele, et. al., to be published, Phys. Rev. A[0pt] [2] M.E. Hanni, et. al., Phys. Rev. A 78, 062510 (2008)

  18. Use of frozen section in genitourinary pathology.

    Science.gov (United States)

    Shen, Steven S; Truong, Luan D; Ro, Jae Y; Ayala, Alberto G

    2012-08-01

    Frozen section diagnosis provides critical information for immediate surgical management decision making. Over the last several years, there have been some significant advances in treatment of genitourinary cancer, particularly with regard to surgical techniques. These changes in turn impact the type and frequency of intraoperative frozen section requests. In this review, we describe the main indications and diagnostic challenges of frozen section diagnosis during surgeries of each genitourinary organ system including prostate, kidney, bladder, testis, and penis. The pitfalls and approaches to different diagnostic situations are discussed. It is also stressed that pathologists must not only be familiar with the histological diagnosis, but also understand the limitations of frozen section diagnosis and communicate with urologists during the intraoperative treatment decision making process.

  19. 21 CFR 146.146 - Frozen concentrated orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen concentrated orange juice. 146.146 Section... Fruit Juices and Beverages § 146.146 Frozen concentrated orange juice. (a) Frozen concentrated orange juice is the food prepared by removing water from the juice of mature oranges as provided in § 146.135...

  20. A new method for detecting the contribution of high Rydberg states to electron-ion recombination

    International Nuclear Information System (INIS)

    Orban, I; Boehm, S; Fogle, M; Paal, A; Schuch, R

    2007-01-01

    A position sensitive detector for measuring field ionized electrons in the fringe field of a dipole magnet is presented. The detector provides a means to study, in a state selective fashion, recombination into high Rydberg states and offers a new method to investigate recombination enhancement effects. Several experimental considerations and possibilities are discussed in the text

  1. Improvement of bacteriological quality of frozen chicken by gamma radiation

    International Nuclear Information System (INIS)

    Nouchpramool, K.; Prachasitthisak, Y.; Charoen, S.; Kanarat, S.; Kanignunta, K.; Tangwongsupang, S.

    1986-12-01

    The possible use of gamma irradiation at doses of 1.6 to 4.0 kGy to improve bacteriological quality of frozen chicken was investigated. The effects of gamma irradiation on salmonella viability in frozen chicken and on sensory quality of frozen chicken were also evaluated. D 10 -values for different isolated strains of salmonella in frozen chicken varied from 0.41 to 0.57 kGy. A dose of 4 kGy is required for a seven log cycle reduction of salmonella contamination in frozen chicken. Approximately 21 per cent of frozen chicken examined were contaminated with salmonella. Salmonella typhimurium, salmonella virchow, and salmonella java were predominant. Irradiation of frozen chicken at a minimum dose of 3.2 kGy eliminated salmonella, coliform, Escherichia coli, and Staphylococcus aureus and, in addition, reduced baterial load by 2 log cycles. Faecal streptococci was still present in a 3.2 kGy samples but in a very small percentage and the count was not over 100 colonies per g. Discoloring of chicken meat was noted after a 2 kGy treatment. The sensory quality of frozen chicken irradiated at 3 and 4 kGy tended to decrease during frozen storage but was within the acceptable range on a nine point hedonic scale even after eight months of frozen storage. Dosage at 3.2 kGy appeared to be sufficient for improving bacteriological quality of frozen chicken

  2. Fundamentals of gas particle flow

    CERN Document Server

    Rudinger, G

    1980-01-01

    Fundamentals of Gas-Particle Flow is an edited, updated, and expanded version of a number of lectures presented on the "Gas-Solid Suspensions” course organized by the von Karman Institute for Fluid Dynamics. Materials presented in this book are mostly analytical in nature, but some experimental techniques are included. The book focuses on relaxation processes, including the viscous drag of single particles, drag in gas-particles flow, gas-particle heat transfer, equilibrium, and frozen flow. It also discusses the dynamics of single particles, such as particles in an arbitrary flow, in a r

  3. Irradiation of Frozen Mincemeat for public Health protection

    International Nuclear Information System (INIS)

    El-Mongy, T.M.; Mohamed, H.M.; Sallam, Y.I.; El-Magoli, B.M.S.

    2000-01-01

    Exposure of frozen mincemeat samples to gamma radiation reduced the initial total bacterial count (8.5x10 5 ) by 0.6, 1.5, 2.9 and 3.6 log cycles, when 2, 4, 6 and 8 kGy doses were applied, respectively. Irradiation, even at the lowest dose applied (2 kGy). destroyed almost the pathogenic and indicator bacteria contaminated mincemeat samples. During frozen storage (-18 degree), the microbial population slightly decreased. No organoleptic of spoilage were detected throughout the storage period (6 months) in irradiated samples receiving doses up to 8 kGy and frozen storage (-18 degree C) of mincemeat for 6 months had no effect on the major constituents of these products (moisture, protein and lipids). Irradiation dose could be increased up to 8 kGy in case of deep frozen mincemeat stored for long period, without any detectable effect upon the acceptability of the product. In the same time 8 kGy is considered quite sufficient to decontaminate potentially pathogens from frozen mincemeat samples. On the basis of economic consideration and the results of this study, 4 kGy could be recommended for irradiation of frozen mincemeat

  4. Sub-wavelength imaging and field mapping via electromagnetically induced transparency and Autler-Townes splitting in Rydberg atoms

    Energy Technology Data Exchange (ETDEWEB)

    Holloway, Christopher L., E-mail: holloway@boulder.nist.gov; Gordon, Joshua A. [National Institute of Standards and Technology (NIST), Electromagnetics Division, U.S. Department of Commerce, Boulder Laboratories, Boulder, Colorado 80305 (United States); Schwarzkopf, Andrew; Anderson, David A.; Miller, Stephanie A.; Thaicharoen, Nithiwadee; Raithel, Georg [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-06-16

    We present a technique for measuring radio-frequency (RF) electric field strengths with sub-wavelength resolution. We use Rydberg states of rubidium atoms to probe the RF field. The RF field causes an energy splitting of the Rydberg states via the Autler-Townes effect, and we detect the splitting via electromagnetically induced transparency (EIT). We use this technique to measure the electric field distribution inside a glass cylinder with applied RF fields at 17.04 GHz and 104.77 GHz. We achieve a spatial resolution of ≈100 μm, limited by the widths of the laser beams utilized for the EIT spectroscopy. We numerically simulate the fields in the glass cylinder and find good agreement with the measured fields. Our results suggest that this technique could be applied to image fields on a small spatial scale over a large range of frequencies, up into the sub-terahertz regime.

  5. Defective Reduction in Frozen Pie Manufacturing Process

    Science.gov (United States)

    Nooted, Oranuch; Tangjitsitcharoen, Somkiat

    2017-06-01

    The frozen pie production has a lot of defects resulting in high production cost. Failure mode and effect analysis (FMEA) technique has been applied to improve the frozen pie process. Pareto chart is also used to determine the major defects of frozen pie. There are 3 main processes that cause the defects which are the 1st freezing to glazing process, the forming process, and the folding process. The Risk Priority Number (RPN) obtained from FMEA is analyzed to reduce the defects. If RPN of each cause exceeds 45, the process will be considered to be improved and selected for the corrective and preventive actions. The results showed that RPN values decreased after the correction. Therefore, the implementation of FMEA technique can help to improve the performance of frozen pie process and reduce the defects approximately 51.9%.

  6. Physiotherapy in frozen shoulder syndrome - literature review

    Directory of Open Access Journals (Sweden)

    Katarzyna Korabiusz

    2017-08-01

    Full Text Available Introduction: The frozen shoulder syndrome is seen as civilization illness. A significant amount of people suffer from it. The frozen shoulder syndrome is one of the most frequent dysfunctions of pectoral girdle. It is seen as a second frequent reason for visits at General Practicioner. There are three stages of this illness, there are a lot of symptoms, but one that occurs most commonly is pain. This illness can be completely curable. Research goal: Goal of this dissertation is a review of literature about available physiotherapy methods used in frozen shoulder syndrome. Conclusion: Kinesiotherapy, kinesiotaping, criotherapy, LASER, Traebert’s currents, iontophoresis, magnetic fields, ultrasounds, massage, manual therapy and combined therapy   are effective physiotherapy methods used in treating frozen shoulder syndrome. Those methods reduce pain indispositions and increase range of movement in shoulder joint.

  7. Ionization due to the interaction between two Rydberg atoms

    International Nuclear Information System (INIS)

    Robicheaux, F

    2005-01-01

    Using a classical trajectory Monte Carlo method, we have computed the ionization resulting from the interaction between two cold Rydberg atoms. We focus on the products resulting from close interaction between two highly excited atoms. We give information on the distribution of ejected electron energies, the distribution of internal atom energies and the velocity distribution of the atoms and ions after the ionization. If the potential for the atom is not purely Coulombic, the average interaction between two atoms can change from attractive to repulsive giving a Van de Graaff-like mechanism for accelerating atoms. In a small fraction of ionization cases, we find that the ionization leads to a positive molecular ion where all of the distances are larger than 1000 Bohr radii

  8. 48 CFR 870.111-5 - Frozen processed food products.

    Science.gov (United States)

    2010-10-01

    ... products. (3) Frozen bakery products. (b) All procured frozen processed food products that contain meat... frozen bakery products that ship products in interstate commerce are required to comply with the Federal... products. 870.111-5 Section 870.111-5 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS...

  9. Dissociative electron attachment to vibrationally excited H2 molecules involving the 2Σg+ resonant Rydberg electronic state

    International Nuclear Information System (INIS)

    Celiberto, R.; Janev, R.K.; Wadehra, J.M.; Tennyson, J.

    2012-01-01

    Graphical abstract: Dissociative electron attachment cross sections as a function of the incident electron energy and for the initial vibration levels v i = 0–5, 10 of the H 2 molecule. Highlights: ► We calculated electron–hydrogen dissociative attachment cross sections and rates coefficients. ► Collision processes occurring through a resonant Rydberg state are considered. ► Cross sections and rates were obtained for vibrationally excited hydrogen molecules. ► The cross sections exhibit pronounced oscillatory structures. ► A comparison with the process involving the electron–hydrogen resonant ground state is discussed. - Abstract: Dissociative electron attachment cross sections (DEA) on vibrationally excited H 2 molecule taking place via the 2 Σ g + Rydberg-excited resonant state are studied using the local complex potential (LCP) model for resonant collisions. The cross sections are calculated for all initial vibrational levels (v i = 0–14) of the neutral molecule. In contrast to the previously noted dramatic increase in the DEA cross sections with increasing v i , when the process proceeds via the X 2 Σ u + shape resonance of H 2 , for the 2 Σ g + Rydberg resonance the cross sections increase only gradually up to v i = 3 and then decrease. Moreover, the cross sections for v i ⩾ 6 exhibit pronounced oscillatory structures. A discussion of the origin of the observed behavior of calculated cross sections is given. The DEA rate coefficients for all v i levels are also calculated in the 0.5–1000 eV temperature range.

  10. Exciton induced directed motion of unconstrained atoms in an ultracold gas

    Science.gov (United States)

    Leonhardt, K.; Wüster, S.; Rost, J. M.

    2017-03-01

    We demonstrate that through localised Rydberg excitation in a three-dimensional cold atom cloud atomic motion can be rendered directed and nearly confined to a plane, without spatial constraints for the motion of individual atoms. This enables creation and observation of non-adiabatic electronic Rydberg dynamics in atoms accelerated by dipole-dipole interactions under natural conditions. Using the full l = 0, 1 m=0,+/- 1 angular momentum state space, our simulations show that conical intersection crossings are clearly evident, both in atomic position information and excited state spectra of the Rydberg system. Hence, flexible Rydberg aggregates suggest themselves for probing quantum chemical effects in experiments on length scales much inflated as compared to a standard molecular situation.

  11. Frozen soil parameterization in a distributed biosphere hydrological model

    Directory of Open Access Journals (Sweden)

    L. Wang

    2010-03-01

    Full Text Available In this study, a frozen soil parameterization has been modified and incorporated into a distributed biosphere hydrological model (WEB-DHM. The WEB-DHM with the frozen scheme was then rigorously evaluated in a small cold area, the Binngou watershed, against the in-situ observations from the WATER (Watershed Allied Telemetry Experimental Research. First, by using the original WEB-DHM without the frozen scheme, the land surface parameters and two van Genuchten parameters were optimized using the observed surface radiation fluxes and the soil moistures at upper layers (5, 10 and 20 cm depths at the DY station in July. Second, by using the WEB-DHM with the frozen scheme, two frozen soil parameters were calibrated using the observed soil temperature at 5 cm depth at the DY station from 21 November 2007 to 20 April 2008; while the other soil hydraulic parameters were optimized by the calibration of the discharges at the basin outlet in July and August that covers the annual largest flood peak in 2008. With these calibrated parameters, the WEB-DHM with the frozen scheme was then used for a yearlong validation from 21 November 2007 to 20 November 2008. Results showed that the WEB-DHM with the frozen scheme has given much better performance than the WEB-DHM without the frozen scheme, in the simulations of soil moisture profile at the cold regions catchment and the discharges at the basin outlet in the yearlong simulation.

  12. Frozen orbit realization using LQR analogy

    Science.gov (United States)

    Nagarajan, N.; Rayan, H. Reno

    In the case of remote sensing orbits, the Frozen Orbit concept minimizes altitude variations over a given region using passive means. This is achieved by establishing the mean eccentricity vector at the orbital poles i.e., by fixing the mean argument of perigee at 90 deg with an appropriate eccentricity to balance the perturbations due to zonal harmonics J2 and J3 of the Earth's potential. Eccentricity vector is a vector whose magnitude is the eccentricity and direction is the argument of perigee. The launcher dispersions result in an eccentricity vector which is away from the frozen orbit values. The objective is then to formulate an orbit maneuver strategy to optimize the fuel required to achieve the frozen orbit in the presence of visibility and impulse constraints. It is shown that the motion of the eccentricity vector around the frozen perigee can be approximated as a circle. Combining the circular motion of the eccentricity vector around the frozen point and the maneuver equation, the following discrete equation is obtained. X(k+1) = AX(k) + Bu(k), where X is the state (i.e. eccentricity vector components), A the state transition matrix, u the scalar control force (i.e. dV in this case) and B the control matrix which transforms dV into eccentricity vector change. Based on this, it is shown that the problem of optimizing the fuel can be treated as a Linear Quadratic Regulator (LQR) problem in which the maneuver can be solved by using control system design tools like MATLAB by deriving an analogy LQR design.

  13. Dynamic polarizabilities and Rydberg states of the argon isoelectronic sequence

    International Nuclear Information System (INIS)

    Ghosh, T.K.; Das, A.K.; Castro, M.; Canuto, S.; Mukherjee, P.K.

    1993-01-01

    Dynamic dipole polarizabilities α d (ω) have been calculated within and beyond the normal-dispersion region for the isoelectronic members of argon up to Mn 7+ using time-dependent coupled Hartree-Fock theory. Excitation energies, oscillator strengths, and quantum-defect values have been estimated for the dipole-allowed transitions 3p 6 1 Se→3p 5 ( 2 P)ns 1 Po (n=4,...,7) and 3p 6 1 Se→3p 5 ( 2 P)nd 1 Po (n=3,...,7). Analytic representations of the singly excited Rydberg orbitals have been obtained. The results compare favorably with the existing theoretical and experimental data. The oscillator strengths show an interesting trend of variation along the isoelectronic sequence

  14. Radiative transitions from Rydberg states of lithium atoms in a blackbody radiation environment

    Science.gov (United States)

    Glukhov, I. L.; Ovsiannikov, V. D.

    2012-05-01

    The radiative widths induced by blackbody radiation (BBR) were investigated for Rydberg states with principal quantum number up to n = 1000 in S-, P- and D-series of the neutral lithium atom at temperatures T = 100-3000 K. The rates of BBR-induced decays and excitations were compared with the rates of spontaneous decays. Simple analytical approximations are proposed for accurate estimations of the ratio of thermally induced decay (excitation) rates to spontaneous decay rates in wide ranges of states and temperatures.

  15. The population transfer of high excited states of Rydberg lithium atoms in a microwave field

    International Nuclear Information System (INIS)

    Jiang Lijuan; Zhang Xianzhou; Ma Huanqiang; Jia Guangrui; Zhang Yonghui; Xia Lihua

    2012-01-01

    Using the time-dependent multilevel approach (TDMA), the properties of high excited Rydberg lithium atom have been obtained in the microwave field. The population transfer of lithium atom are studied on numerical calculation, quantum states are controlled and manipulated by microwave field. It shows that the population can be completely transferred to the target state by changing the chirped rate and field amplitude. (authors)

  16. 78 FR 45907 - United States Standards for Grades of Frozen Vegetables

    Science.gov (United States)

    2013-07-30

    ..., frozen cooked squash, frozen summer squash, frozen sweetpotatoes, frozen turnip greens with turnips, and... standards to better serve the industry. A 60-day period was provided for interested persons to submit... and their suppliers. AFFI's more than 500 member companies represent approximately 90 percent of the...

  17. Inner-shell spectroscopy and exchange interaction of Rydberg electrons bound by singly and doubly charged Kr and Xe atoms in small clusters

    International Nuclear Information System (INIS)

    Nagasaka, Masanari; Hatsui, Takaki; Setoyama, Hiroyuki; Ruehl, Eckart; Kosugi, Nobuhiro

    2011-01-01

    Surface-site resolved Kr 3d 5/2 -1 5p and 3d 5/2 -1 6p and Xe 4d 5/2 -1 6p and 4d 5/2 -1 7p Rydberg excited states in small van der Waals Kr and Xe clusters with a mean size of = 15 are investigated by X-ray absorption spectroscopy. Furthermore, surface-site resolved Kr 4s -2 5p, 4s -2 6p, and 4s -1 4p -1 5p shakeup-like Rydberg states in small Kr clusters are investigated by resonant Auger electron spectroscopy. The exchange interaction of the Rydberg electron with the surrounding atoms and the induced polarization of the surrounding atoms in the singly and doubly ionized atoms are deduced from the experimental spectra to analyze different surface-site contributions in small clusters, assuming that the corner, edge, face, and bulk sites have 3, 5-6, 8, and 12 nearest neighbor atoms. These energies are almost proportional to the number of the nearest neighbor atoms. The present analysis indicates that small Kr and Xe clusters with = 15 have an average or mixture structure between the fcc-like cubic and icosahedron-like spherical structures.

  18. Biochemical effects on long-term frozen human costal cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Santin, Stefany P.; Martinho Junior, Antonio C.; Yoshito, Daniele; Soares, Fernando A.N.; Mathor, Monica B., E-mail: mathor@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Currently, the progresses on treatment of musculoskeletal diseases with the evolving of artificial implants and the success of tissue transplantation between genetically different individuals have conducted to an increase in radiosterilization. Regarding to tissue transplantation, it is essential to have sterile tissue and many tissue banks use radiosterilization as an effective method to sterilize these tissues. However, high doses of ionizing radiation and the preservation method may induce structural modifications in the tissues, as degradation of structural scaffold, decreasing its mechanical properties. Particularly, cartilage have been preserved in high concentrations of glycerol or deep-frozen at -70 degree C for storage after radiosterilization. Therefore, it is important to study the modifications induced in cartilage by preservation methods and by radiosterilization to determine the appropriated parameters for high quality of human allografts. Costal cartilages were obtained from cadaveric donors and were frozen at -20 degree C for 2 years long in order to compare with previous studies for fresh, deep-frozen and glycerolised cartilages. The mechanical tests were carried out in a universal testing machine until sample failure. According our results, there is no significant statistical difference between stress at break of fresh, long-term - 20 degree C frozen cartilages and deep-frozen cartilage. This early result suggests, regarding to tensile property, that long-term - 20 degree C frozen cartilages corresponds to glycerolised costal cartilages irradiated with 25 kGy or deep-frozen cartilages irradiated with 25 and 50 kGy. Thus, this long-term frozen cartilages may be used for tissue banks, but more studies about effects of ionizing radiation are necessary. (author)

  19. Biochemical effects on long-term frozen human costal cartilage

    International Nuclear Information System (INIS)

    Santin, Stefany P.; Martinho Junior, Antonio C.; Yoshito, Daniele; Soares, Fernando A.N.; Mathor, Monica B.

    2011-01-01

    Currently, the progresses on treatment of musculoskeletal diseases with the evolving of artificial implants and the success of tissue transplantation between genetically different individuals have conducted to an increase in radiosterilization. Regarding to tissue transplantation, it is essential to have sterile tissue and many tissue banks use radiosterilization as an effective method to sterilize these tissues. However, high doses of ionizing radiation and the preservation method may induce structural modifications in the tissues, as degradation of structural scaffold, decreasing its mechanical properties. Particularly, cartilage have been preserved in high concentrations of glycerol or deep-frozen at -70 degree C for storage after radiosterilization. Therefore, it is important to study the modifications induced in cartilage by preservation methods and by radiosterilization to determine the appropriated parameters for high quality of human allografts. Costal cartilages were obtained from cadaveric donors and were frozen at -20 degree C for 2 years long in order to compare with previous studies for fresh, deep-frozen and glycerolised cartilages. The mechanical tests were carried out in a universal testing machine until sample failure. According our results, there is no significant statistical difference between stress at break of fresh, long-term - 20 degree C frozen cartilages and deep-frozen cartilage. This early result suggests, regarding to tensile property, that long-term - 20 degree C frozen cartilages corresponds to glycerolised costal cartilages irradiated with 25 kGy or deep-frozen cartilages irradiated with 25 and 50 kGy. Thus, this long-term frozen cartilages may be used for tissue banks, but more studies about effects of ionizing radiation are necessary. (author)

  20. Lactose-free frozen yogurt: production and characteristics.

    Science.gov (United States)

    Skryplonek, Katarzyna; Gomes, David; Viegas, Jorge; Pereira, Carlos; Henriques, Marta

    2017-01-01

    Nowadays, consumer demand is driving better and more nutritious dairy products. Changing from traditional to new lactose-free products poses technological challenges for the food industry in order to maintain or improve their food characteristics and consumer preferences. This study investigates the production of lactose-free frozen yogurt by enzymati- cally hydrolysis of lactose, and its influence on the final product characteristics. In the case of lactose-free products, commercial Ha-lactase® was used for hydrolysis, and the reaction occurred simultaneously with fermentation. The effect of lactose hydrolysis on the physicochemical properties, texture, viscosity, overrun and sensory attributes in the final product was investigated. After yogurt maturation, the acidity of the lactose-free product was significantly higher than in the control, suggesting that breaking down lactose enhances the fermentation process. Lactose-free frozen yogurt had significantly lower hardness and stickiness and higher viscosity than control frozen yogurt. Moreover, lactose hydrolysis promoted a smooth and creamy consistency, whereas in the case of conventional prod- ucts a coarse structure, due to the presence of large ice crystals, was identified. Hydrolysis of lactose also improved the sweetness and brightness of frozen yogurt. The improved textural properties of lactose-free product results from the fact that monosaccharides produced during lactose hydrolysis depress the freezing point of the mix, which enables product with softer structure and bigger resistance to ice recrystallization to be obtained. The study showed that lactose-free frozen yogurt may be used successfully for production of novel lactose-free frozen desserts. Lactose hydrolysis improves the texture and viscosity of the product,     as well as enhancing its sensory quality.

  1. Inactivation of Salmonellae in Frozen Catfish by Gamma Irradiation

    International Nuclear Information System (INIS)

    Nouchpramoon, Kovit; Amsiri, Jarurat

    2003-06-01

    The effect of gamma irradiation on salmonellae viability in frozen catfish was investigated using fresh cut of catfish artificially contaminated with stationary phase cells of salmonellae, frozen at-18 οC and irradiated with does ranging from 0.0 to 2.4 kGy. The D 10 values for ten serovars of salmonellae ranged from 0.47 to 0.77 kGy. Salmonella Enteritidis was the most resistant serovars found in frozen catfish. Dosage at 2.5 kGy would be sufficient to kill 10 3 . 2 Salmonella Enteritidis that may occasionally present in frozen catfish

  2. Influence of increasing nuclear charge on the Rydberg spectra of Xe, Cs+, and Ba++: Correlation, term dependence, and autoionization

    International Nuclear Information System (INIS)

    Hill, W.T. III; Cheng, K.T.; Johnson, W.R.; Lucatorto, T.B.; McIlrath, T.J.; Sugar, J.

    1982-01-01

    The first experimental-theoretical study of Rydberg autoionizing resonances along an isoelectronic sequence is presented. This analysis demonstrates the intimate connection between electron-electron correlation, term-dependence, and autoionization and underscores the power of multichannel quantum defect theory in analyzing complex spectra

  3. Ionization of H Rydberg atoms

    International Nuclear Information System (INIS)

    Hillermier, C.F.; Bluemental, R.; Smilansky, U.

    1991-07-01

    Concepts from the theory of transient chaos are applied to study the classical ionization process of one dimensional model of kicked hydrogen Rydberg atoms. The phase-space dynamics is represented by a mapping T which is proved to be hyperbolic. The fraction of atoms not ionized after time t, P B (t), decays asymptotically according to P B (t)∼t -α with α ∼ 1.65. The observed algebraic decay, which seems to contradict the hyperbolicity of T, is explained by (i) the symbolic dynamics of T consists of a countably infinite number of symbols and (ii) the invariant manifold of phase-space points which never ionize is an anomalously scaling fractal. Therefore, the one-dimensional kicked hydrogen atom provides a counterexample to the hypothesis that algebraic decay marks regular dynamics, whereas hyperbolic systems decay exponentially. The algebraic decay is reproduced by an analytically solvable diffusion model which predicts α = 3/2. Replacing zero-width δ-kicks by smooth finite-width pulses, the mapping T is no longer completely hyperbolic, and a subset of phase-space is regular. For this case we observe that P B (t) shows a transition between two power-law decays with α ∼ 1.65 for short times and α ∼ 2.1 for long times where the effect of the regular domain is felt. (author)

  4. Competition between font face="Symbol">Lfont>- and V-type transitions in interference stabilization of Rydberg atoms.

    Science.gov (United States)

    Fedorov, M; Poluektov, N

    1998-01-19

    The problem of Interference Stabilization of Rydberg atoms is considered. Two kinds of Raman-type transitions can be responsible for the effect: L-type transitions via the continuum and V-type transitions via lower resonant atomic levels. The main distinctions between L- and V- stabilization are described. The conditions under which each of these two effects can exist are found and discussed.

  5. Lifetime measurements of highly excited Rydberg states of strontium. Pt. 1

    International Nuclear Information System (INIS)

    Kunze, S.; Hohmann, R.; Kluge, H.J.; Lantzsch, J.; Monz, L.; Stenner, J.; Stratmann, K.; Wendt, K.; Zimmer, K.

    1993-01-01

    Lifetimes of Rydberg states of triplet-series 5s ns 3 S 1 with n=19-23, 35 and 5s nd 3 D 3 with n=18-20, 23-28 in the spectrum of neutral strontium have been determined. Observation of the exponential decay after excitation by a pulsed laser in a fast atomic beam and subsequent state-selective field ionization was employed. The lifetimes of the states of the 3 S 1 -series show the expected n* 3 dependence on the effective principal quantum number, while the 3 D 3 -series is disturbed by configuration mixing. Furthermore, state re-populations induced by black-body radiation have been observed. (orig.)

  6. Line shapes and time dynamics of the Förster resonances between two Rydberg atoms in a time-varying electric field

    KAUST Repository

    Yakshina, E. A.

    2016-10-21

    The observation of the Stark-tuned Förster resonances between Rydberg atoms excited by narrowband cw laser radiation requires usage of a Stark-switching technique in order to excite the atoms first in a fixed electric field and then to induce the interactions in a varied electric field, which is scanned across the Förster resonance. In our experiments with a few cold Rb Rydberg atoms, we have found that the transients at the edges of the electric pulses strongly affect the line shapes of the Förster resonances, since the population transfer at the resonances occurs on a time scale of ∼100 ns, which is comparable with the duration of the transients. For example, a short-term ringing at a certain frequency causes additional radio-frequency-assisted Förster resonances, while nonsharp edges lead to asymmetry. The intentional application of the radio-frequency field induces transitions between collective states, whose line shape depends on the interaction strengths and time. Spatial averaging over the atom positions in a single interaction volume yields a cusped line shape of the Förster resonance. We present a detailed experimental and theoretical analysis of the line shape and time dynamics of the Stark-tuned Förster resonances Rb(nP3/2)+Rb(nP3/2)→Rb(nS1/2)+Rb([n+1]S1/2) for two Rb Rydberg atoms interacting in a time-varying electric field.

  7. Line shapes and time dynamics of the Förster resonances between two Rydberg atoms in a time-varying electric field

    KAUST Repository

    Yakshina, E. A.; Tretyakov, D. B.; Beterov, I. I.; Entin, V. M.; Andreeva, C.; Cinins, A.; Markovski, A.; Iftikhar, Z.; Ekers, Aigars; Ryabtsev, I. I.

    2016-01-01

    The observation of the Stark-tuned Förster resonances between Rydberg atoms excited by narrowband cw laser radiation requires usage of a Stark-switching technique in order to excite the atoms first in a fixed electric field and then to induce the interactions in a varied electric field, which is scanned across the Förster resonance. In our experiments with a few cold Rb Rydberg atoms, we have found that the transients at the edges of the electric pulses strongly affect the line shapes of the Förster resonances, since the population transfer at the resonances occurs on a time scale of ∼100 ns, which is comparable with the duration of the transients. For example, a short-term ringing at a certain frequency causes additional radio-frequency-assisted Förster resonances, while nonsharp edges lead to asymmetry. The intentional application of the radio-frequency field induces transitions between collective states, whose line shape depends on the interaction strengths and time. Spatial averaging over the atom positions in a single interaction volume yields a cusped line shape of the Förster resonance. We present a detailed experimental and theoretical analysis of the line shape and time dynamics of the Stark-tuned Förster resonances Rb(nP3/2)+Rb(nP3/2)→Rb(nS1/2)+Rb([n+1]S1/2) for two Rb Rydberg atoms interacting in a time-varying electric field.

  8. Combined theoretical and experimental study of the valence, Rydberg and ionic states of fluorobenzene

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, Michael H., E-mail: m.h.palmer@ed.ac.uk; Ridley, Trevor [School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, Scotland EH9 3FJ (United Kingdom); Vrønning Hoffmann, Søren, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: Teng.Zhang@physics.uu.se, E-mail: biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu; Jones, Nykola C., E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: Teng.Zhang@physics.uu.se, E-mail: biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Coreno, Marcello, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: Teng.Zhang@physics.uu.se, E-mail: biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [CNR-ISM, Basovizza Area Science Park, 1-34149 Trieste (Italy); De Simone, Monica, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: Teng.Zhang@physics.uu.se, E-mail: biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [CNR-IOM Laboratorio TASC, Trieste (Italy); Grazioli, Cesare [CNR-IOM Laboratorio TASC, Trieste (Italy); Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste (Italy); Zhang, Teng, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: Teng.Zhang@physics.uu.se, E-mail: biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [Department of Physics and Astronomy, University of Uppsala, Uppsala (Sweden); and others

    2016-05-28

    New photoelectron spectra (PES) and ultra violet (UV) and vacuum UV (VUV) absorption spectra of fluorobenzene recorded at higher resolution than previously, have been combined with mass-resolved (2 + 1) and (3 + 1) resonance enhanced multiphoton ionization (REMPI) spectra; this has led to the identification of numerous Rydberg states. The PES have been compared with earlier mass-analyzed threshold ionization and photoinduced Rydberg ionization (PIRI) spectra to give an overall picture of the ionic state sequence. The analysis of these spectra using both equations of motion with coupled cluster singles and doubles (EOM-CCSD) configuration interaction and time dependent density functional theory (TDDFT) calculations have been combined with vibrational analysis of both the hot and cold bands of the spectra, in considerable detail. The results extend several earlier studies on the vibronic coupling leading to conical intersections between the X{sup 2}B{sub 1} and A{sup 2}A{sub 2} states, and a further trio (B, C, and D) of states. The conical intersection of the X and A states has been explicitly identified, and its structure and energetics evaluated. The energy sequence of the last group is only acceptable to the present study if given as B{sup 2}B{sub 2}

  9. Quantum-optical magnets with competing short- and long-range interactions: Rydberg-dressed spin lattice in an optical cavity

    Directory of Open Access Journals (Sweden)

    Jan Gelhausen, Michael Buchhold, Achim Rosch, Philipp Strack

    2016-10-01

    Full Text Available The fields of quantum simulation with cold atoms [1] and quantum optics [2] are currently being merged. In a set of recent pathbreaking experiments with atoms in optical cavities [3,4] lattice quantum many-body systems with both, a short-range interaction and a strong interaction potential of infinite range -mediated by a quantized optical light field- were realized. A theoretical modelling of these systems faces considerable complexity at the interface of: (i spontaneous symmetry-breaking and emergent phases of interacting many-body systems with a large number of atoms $N\\rightarrow\\infty$, (ii quantum optics and the dynamics of fluctuating light fields, and (iii non-equilibrium physics of driven, open quantum systems. Here we propose what is possibly the simplest, quantum-optical magnet with competing short- and long-range interactions, in which all three elements can be analyzed comprehensively: a Rydberg-dressed spin lattice [5] coherently coupled to a single photon mode. Solving a set of coupled even-odd sublattice Master equations for atomic spin and photon mean-field amplitudes, we find three key results. (R1: Superradiance and a coherent photon field can coexist with spontaneously broken magnetic translation symmetry. The latter is induced by the short-range nearest-neighbor interaction from weakly admixed Rydberg levels. (R2: This broken even-odd sublattice symmetry leaves its imprint in the light via a novel peak in the cavity spectrum beyond the conventional polariton modes. (R3: The combined effect of atomic spontaneous emission, drive, and interactions can lead to phases with anomalous photon number oscillations. Extensions of our work include nano-photonic crystals coupled to interacting atoms and multi-mode photon dynamics in Rydberg systems.

  10. Microwave spectroscopy of the 1 s n p P3J fine structure of high Rydberg states in 4He

    Science.gov (United States)

    Deller, A.; Hogan, S. D.

    2018-01-01

    The 1 s n p P3J fine structure of high Rydberg states in helium has been measured by microwave spectroscopy of single-photon transitions from 1 s n s S31 levels in pulsed supersonic beams. For states with principal quantum numbers in the range from n =34 to 36, the J =0 →2 and J =1 →2 fine structure intervals were both observed. For values of n between 45 and 51 only the larger J =0 →2 interval was resolved. The experimental results are in good agreement with theoretical predictions. Detailed characterization of residual uncanceled electric and magnetic fields in the experimental apparatus and calculations of the Stark and Zeeman structures of the Rydberg states in weak fields were used to quantify systematic contributions to the uncertainties in the measurements.

  11. Analysis of high-n dielectronic Rydberg satellites in the spectra of Na-like Zn XX and Mg-like Zn XIX

    International Nuclear Information System (INIS)

    Fournier, K.B.; Faenov, A.Ya.; Pikuz, T.A.; Magunov, A.I.; Skobelev, I.Yu.; Flora, F.; Bollanti, S.; Di Lazzaro, P.; Murra, D.; Belyaev, V.S.; Vinogradov, V.I.; Kyrilov, A.S.; Matafonov, A.P.; Francucci, M.; Martellucci, S.; Petrocelli, G.

    2004-01-01

    We have observed spectra from highly charged zinc ions in a variety of laser-produced plasmas. Spectral features that are Na- and Mg-like satellites to high-n Rydberg transitions in the Ne-like Zn XXI spectrum are analyzed and modeled. Identifications and analysis are made by comparison with highly accurate atomic structure calculations and steady state collisional-radiative models. Each observed Zn XX and Zn XIX feature comprises up to ≅2 dozen individual transitions, these transitions are excited principally by dielectronic recombination through autoionizing levels in Na- and Mg-like Zn 19+ and Zn 18+ . We find these satellites to be ubiquitous in laser-produced plasmas formed by lasers with pulse lengths that span four orders of magnitude, from 1 ps to ≅10 ns. The diagnostic potential of these Rydberg satellite lines is demonstrated

  12. Splitting of an electromagnetically induced transparency window of a cascade system with 133Cs Rydberg atoms in a static magnetic field

    International Nuclear Information System (INIS)

    Bao Shanxia; Yang Wenguang; Zhang Hao; Zhang Linjie; Zhao Jianming; Jia Suotang

    2015-01-01

    We investigate the electromagnetically induced transparency (EIT) of 133 Cs vapor at the room temperature in a magnetic field. In a cascade three-level system involved Rydberg state, two collinearly counter-propagating and orthogonally linear-polarized laser fields act on cascaded two transitions, 6S 1/2 → 6P 3/2 and 6P 3/2 ↔ 47D 5/2 , respectively. The EIT window become broadening and split into several sub-EIT windows when the magnetic field is applied. The dependences of splitting shape and intervals of sub-EIT windows on magnetic field are measured experimentally and compared with the theoretical calculation considering the different magnetic effects on ground state, low excited state and Rydberg state. The splitting intervals of sub-EIT windows are well consistent with theoretical calculation. (author)

  13. The rate coefficients for the processes of (n - n')-mixing in collisions of Rydberg atoms H*(n) with H(1s) atoms

    International Nuclear Information System (INIS)

    Mihajlov, A A; Ignjatovic, Lj M; Djuric, Z; Ljepojevic, N N

    2004-01-01

    This paper presents the results of semi-classical calculations of rate coefficients of (n - n')-mixing processes in collisions of Rydberg atoms H*(n) with H(1s) atoms. These processes have been modelled by the mechanism of the resonant energy exchange within the electron component of the H*(n) + H collisional system. The calculations of the rate coefficients, based on this model, were performed for the series of principal quantum numbers, n and n', and atomic, T a , and electronic, T e , temperatures. It was shown that these processes can be of significant influence on the populations of Rydberg atoms in weakly ionized plasmas (ionization degree ∼ -4 ), and therefore have to be included in appropriate models of such plasmas

  14. Modeling snowmelt infiltration in seasonally frozen ground

    Science.gov (United States)

    Budhathoki, S.; Ireson, A. M.

    2017-12-01

    In cold regions, freezing and thawing of the soil govern soil hydraulic properties that shape the surface and subsurface hydrological processes. The partitioning of snowmelt into infiltration and runoff has also important implications for integrated water resource management and flood risk. However, there is an inadequate representation of the snowmelt infiltration into frozen soils in most land-surface and hydrological models, creating the need for improved models and methods. Here we apply, the Frozen Soil Infiltration Model, FroSIn, which is a novel algorithm for infiltration in frozen soils that can be implemented in physically based models of coupled flow and heat transport. In this study, we apply the model in a simple configuration to reproduce observations from field sites in the Canadian prairies, specifically St Denis and Brightwater Creek in Saskatchewan, Canada. We demonstrate the limitations of conventional approaches to simulate infiltration, which systematically over-predict runoff and under predict infiltration. The findings show that FroSIn enables models to predict more reasonable infiltration volumes in frozen soils, and also represent how infiltration-runoff partitioning is impacted by antecedent soil moisture.

  15. Time-resolved Fourier-transform infrared emission spectroscopy of Au in the 1800-4000-cm(-1) region: Rydberg transitions

    Czech Academy of Sciences Publication Activity Database

    Civiš, Svatopluk; Matulková, Irena; Cihelka, Jaroslav

    2010-01-01

    Roč. 81, č. 1 (2010), 012510 ISSN 1050-2947 R&D Projects: GA AV ČR IAA400400705; GA AV ČR KAN100500652 Institutional research plan: CEZ:AV0Z40400503 Keywords : spectroscopy * Rydberg transitions * theoretical chemistry Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.861, year: 2010

  16. Microwave multiphoton excitation of helium Rydberg atoms: The analogy with atomic collisions

    International Nuclear Information System (INIS)

    van de Water, W.; van Leeuwen, K.A.H.; Yoakum, S.; Galvez, E.J.; Moorman, L.; Bergeman, T.; Sauer, B.E.; Koch, P.M.

    1989-01-01

    We study multiphoton transitions in helium Rydberg atoms subjected to a microwave electric field of fixed frequency but varying intensity. For each principal quantum number in the range n=25--32, the n 3 S to n 3 (L>2), n=25--32, transition probability exhibits very sharp structures as a function of the field amplitude. Their positions could be reproduced precisely using a Floquet Hamiltonian for the interaction between atom and field. Their shapes are determined by the transients of field turn-on and turn-off in a way that makes a close analogy with the theory of slow atomic collisions

  17. Rydberg states in a microwave field: regularity and chaos; Atomes de rydberg en champ micro-onde: regularite et chaos

    Energy Technology Data Exchange (ETDEWEB)

    Buchleitner, A

    1993-12-15

    We develop a theoretical formalism which provides a powerful tool for the detailed numerical analysis of the interaction of three-dimensional hydrogen atoms with an intense radiation field. The application of this approach to the microwave ionization of Rydberg states of hydrogen provides the most realistic numerical experiments ever made in this area. A thorough analysis of ionization signals and thresholds, of level dynamics and of the phase space projections of associated wave functions is provided for a one-dimensional model of the atom. The comparison to the ionization of three-dimensional atoms confirms the validity of the one-dimensional model for extended initial states and, hence, dynamical localization theory, as far as the ionization threshold is concerned. Three classes of three-dimensional initial states with distinct symmetries are identified and they appear to be more or less adapted to the symmetries of the eigenstates of the microwave problem. 'Scarred' wavefunctions of the three-dimensional hydrogen atom exposed to microwave field are shown. Finally, the dynamics of a circular state in a microwave and in an intense laser field are compared. (author)

  18. Population coherent control of Rydberg potassium atom via adiabatic passage

    International Nuclear Information System (INIS)

    Jiang Li-Juan; Zhang Xian-Zhou; Jia Guang-Rui; Zhang Yong-Hui; Xia Li-Hua

    2013-01-01

    The time-dependent multilevel approach (TDMA) and B-spline expansion technique are used to study the coherent population transfer between the quantum states of a potassium atom by a single frequency-chirped microwave pulse. The Rydberg potassium atom energy levels of n = 6–15, l = 0–5 states in zero field are calculated and the results are in good agreement with other theoretical values. The time evolutions of the population transfer of the six states from n = 70 to n = 75 in different microwave fields are obtained. The results show that the coherent control of the population transfer from the lower states to the higher ones can be accomplished by optimizing the microwave pulse parameters. (atomic and molecular physics)

  19. Detailed Balance of Thermalization Dynamics in Rydberg-Atom Quantum Simulators.

    Science.gov (United States)

    Kim, Hyosub; Park, YeJe; Kim, Kyungtae; Sim, H-S; Ahn, Jaewook

    2018-05-04

    Dynamics of large complex systems, such as relaxation towards equilibrium in classical statistical mechanics, often obeys a master equation that captures essential information from the complexities. Here, we find that thermalization of an isolated many-body quantum state can be described by a master equation. We observe sudden quench dynamics of quantum Ising-like models implemented in our quantum simulator, defect-free single-atom tweezers in conjunction with Rydberg-atom interaction. Saturation of their local observables, a thermalization signature, obeys a master equation experimentally constructed by monitoring the occupation probabilities of prequench states and imposing the principle of the detailed balance. Our experiment agrees with theories and demonstrates the detailed balance in a thermalization dynamics that does not require coupling to baths or postulated randomness.

  20. Detailed Balance of Thermalization Dynamics in Rydberg-Atom Quantum Simulators

    Science.gov (United States)

    Kim, Hyosub; Park, YeJe; Kim, Kyungtae; Sim, H.-S.; Ahn, Jaewook

    2018-05-01

    Dynamics of large complex systems, such as relaxation towards equilibrium in classical statistical mechanics, often obeys a master equation that captures essential information from the complexities. Here, we find that thermalization of an isolated many-body quantum state can be described by a master equation. We observe sudden quench dynamics of quantum Ising-like models implemented in our quantum simulator, defect-free single-atom tweezers in conjunction with Rydberg-atom interaction. Saturation of their local observables, a thermalization signature, obeys a master equation experimentally constructed by monitoring the occupation probabilities of prequench states and imposing the principle of the detailed balance. Our experiment agrees with theories and demonstrates the detailed balance in a thermalization dynamics that does not require coupling to baths or postulated randomness.

  1. Calculation of thermal conductivity of frozen food

    International Nuclear Information System (INIS)

    Orrego A, Carlos E.

    1998-01-01

    A simple model is presented for the presage of the thermal conductivities of frozen foods that combines different authors' proposals. For varied materials on those that there is available information of the modification of this property with the temperature in frozen systems, the comparison of the dear and empiric values is made to evaluate these predictions

  2. Clinical Outcomes after Arthroscopic Release for Recalcitrant Frozen Shoulder

    OpenAIRE

    Ebrahimzadeh, Mohammad H; Moradi, Ali; Pour, Mostafa Khalili; Moghadam, Mohammad Hallaj; Kachooei, Amir Reza

    2014-01-01

    Background: To explain the role of arthroscopic release in intractable frozen shoulders. We used different questionnaires and measuring tools to understand whether arthroscopic release is the superior modality to treat patients with intractable frozen shoulders. Methods: Between 2007 and 2013, in a prospective study, we enrolled 80 patients (52 females and 28 males) with recalcitrant frozen shoulder, who underwent arthroscopic release at Ghaem Hospital, a tertiary referral center, in Mashhad,...

  3. 21 CFR 146.148 - Reduced acid frozen concentrated orange juice.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Reduced acid frozen concentrated orange juice. 146... Canned Fruit Juices and Beverages § 146.148 Reduced acid frozen concentrated orange juice. (a) Reduced acid frozen concentrated orange juice is the food that complies with the requirements for composition...

  4. Theory of collisional excitation transition between Rydberg states of atoms. Non-inertial mechanism

    International Nuclear Information System (INIS)

    Kaulakys, B.P.

    1982-01-01

    The transitions between highly states of an atom due to the collision of its core with another atom are considered. The cross sections of the change of highly excited electron angular momentum, in the case of the transitions when the main quantum number is constant, are expressed in terms of transport cross sections of the perturbing atom scattering on the ion of Rydberg atom. It is shown that the cross sections of the momentum mixing at thermal rapidities are lower than the cross sections of the atom-ion elastic scattering

  5. Chemical reaction dynamics of Rydberg atoms with neutral molecules: A comparison of molecular-beam and classical trajectory results for the H(n)+D2→HD+D(n') reaction

    International Nuclear Information System (INIS)

    Song Hui; Dai Dongxu; Wu Guorong; Wang, C.-C.; Harich, Steven A.; Hayes, Michael Y.; Wang Xiuyan; Gerlich, Dieter; Yang Xueming; Skodje, Rex T.

    2005-01-01

    Recent molecular-beam experiments have probed the dynamics of the Rydberg-atom reaction, H(n)+D 2 →HD+D(n) at low collision energies. It was discovered that the rotationally resolved product distribution was remarkably similar to a much more limited data set obtained at a single scattering angle for the ion-molecule reaction H + +D 2 →D + +HD. The equivalence of these two problems would be consistent with the Fermi-independent-collider model (electron acting as a spectator) and would provide an important new avenue for the study of ion-molecule reactions. In this work, we employ a classical trajectory calculation on the ion-molecule reaction to facilitate a more extensive comparison between the two systems. The trajectory simulations tend to confirm the equivalence of the ion+molecule dynamics to that for the Rydberg-atom+molecule system. The theory reproduces the close relationship of the two experimental observations made previously. However, some differences between the Rydberg-atom experiments and the trajectory simulations are seen when comparisons are made to a broader data set. In particular, the angular distribution of the differential cross section exhibits more asymmetry in the experiment than in the theory. The potential breakdown of the classical model is discussed. The role of the 'spectator' Rydberg electron is addressed and several crucial issues for future theoretical work are brought out

  6. Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

    Science.gov (United States)

    Abdelazez, Amro; Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao; Abdelmotaal, Heba; Sami, Rokayya; Meng, Xiang-Chen

    2017-01-01

    Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. ( Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture ( Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at -18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

  7. Radiotreated cocoa powder for frozen elaboration

    International Nuclear Information System (INIS)

    Rodriguez Jorge, M.; Alvarez Gil, M.; Prieto Miranda, E.; Morales Valladares, M.

    1995-01-01

    The aim of the present papers is to study the possibilities of 2.0 kGy gamma radiotreated cocoa powder to be used in the elaboration of powder mixture for the preparation of chocolate frozen. Three industrial productions were carried out. Microbiological and organoleptic evaluations of the final product were performed. The results showed that the use of radurized cocoa powder in the frozen elaboration is feasible. A good hygienic quality of this product was obtained and no organoleptic alterations were detected [es

  8. Thawing of Frozen Tuna Meat

    Science.gov (United States)

    Tanaka, Takeo; Nishiwaki, Kôji; Kakuda, Kitonari; Tomimatsu, Takao

    Frozen southern bluefin tuna meat discolors easily and sometimes contracts when thawed caused by thaw rigor. These phenomenon often become problematic in the transaction or handling of this kind of frozen tuna. Frozen meat blocks of southern Bluefin tuna were thawed separately by air thawing, running water thawing and microwave thawing. Changes occurring during thawing were checked for meat color by met-myoglobin ratio determination and for contract by microscopic observation. Results are as follows : (1) Discoloration scarcely occurred in the process of running water thawing (at 10°C for 50 min, or at 0°C for 6 hr). (2) No contraction was observed during thawing with running water described above and air thawing (at 18-20°C for 6 hr). (3) Discoloration and contraction seemed to be minimized, as to latently contractile blocks, when meat temperature passed through rapidly between -10°C and -5°C, and slowly (for 5-6 hr) between -5°C and -1°C. When the block was originally not contractile, discloration was minimized by rising meat temperature rapidly from -10°C to -l°C.

  9. An audit of intraoperative frozen section in Johor.

    Science.gov (United States)

    Khoo, J J

    2004-03-01

    A 4-year-review was carried out on intraoperative frozen section consultations in Sultanah Aminah Hospital, Johor Bahru. Two hundred and fifteen specimens were received from 79 patients in the period between January 1999 and December 2002. An average of 2.72 specimens per patient was received. The overall diagnostic accuracy was high, 97.56%. The diagnoses were deferred in 4.65% of the specimens. False positive diagnoses were made in 3 specimens (1.46%) and false negative diagnoses in 2 specimens (0.98%). This gave an error rate of 2.44%. The main cause of error was incorrect interpretation of the pathologic findings. In the present study, frozen sections showed good sensitivity (97.98%) and specificity (97.16%). Despite its limitations, frozen section is still generally considered to be an accurate mode of intraoperative consultation to assist the surgeon in deciding the best therapeutic approach for his patient at the operating table. The use of frozen section with proper indications was cost-effective as it helped lower the number of reoperations. An audit of intraoperative frozen section from time to time serves as part of an ongoing quality assurance program and should be recommended where the service is available.

  10. Electron scattering in dense He-Ar gas mixtures: A pressure shift study

    International Nuclear Information System (INIS)

    Asaf, U.; Felps, W.S.; McGlynn, S.P.

    1989-01-01

    The dependence of the energies of high-n Rydberg states of CH 3 I on the molar composition of helium-argon mixtures (in the number density range 1.3x10 20 --5.6x10 20 cm -3 ) is reported. The energy shifts, when normalized to a given density value, are found to vary linearly with the mole fraction of either component of the binary, rare-gas mixture. The observed change in sign of the energy shift is attributable to the different signs of the electron scattering lengths for the two rare-gas components. As a result, there exists a mixture composition, at a mole ratio [He]/[Ar]=2.0, at which the shift is null. The experimental results for the gas mixture agree with the Fermi formula, as modified to include the Alekseev-Sobel'man polarization term. Effective electron scattering lengths and cross sections, polarizabilities, and thermal velocities are used to characterize the effects of the binary gas perturber system

  11. The rate coefficients for the processes of (n - n')-mixing in collisions of Rydberg atoms H*(n) with H(1s) atoms

    Energy Technology Data Exchange (ETDEWEB)

    Mihajlov, A A [Institute of Physics, PO Box 57, 11001 Belgrade (Serbia and Montenegro); Ignjatovic, Lj M [Institute of Physics, PO Box 57, 11001 Belgrade (Serbia and Montenegro); Djuric, Z [Silvaco Data Systems, Compass Point, St Ives PE27 5JL (United Kingdom); Ljepojevic, N N [Silvaco Data Systems, Compass Point, St Ives PE27 5JL (United Kingdom)

    2004-11-28

    This paper presents the results of semi-classical calculations of rate coefficients of (n - n')-mixing processes in collisions of Rydberg atoms H*(n) with H(1s) atoms. These processes have been modelled by the mechanism of the resonant energy exchange within the electron component of the H*(n) + H collisional system. The calculations of the rate coefficients, based on this model, were performed for the series of principal quantum numbers, n and n', and atomic, T{sub a}, and electronic, T{sub e}, temperatures. It was shown that these processes can be of significant influence on the populations of Rydberg atoms in weakly ionized plasmas (ionization degree {approx}<10{sup -4}), and therefore have to be included in appropriate models of such plasmas.

  12. Study on irradiation preservation of frozen shelled shrimps

    International Nuclear Information System (INIS)

    Liu Chunquan; Zhu Jiating; Zhao Yongfu; Yu Gang; Zhang Weidong; Jin Yudong; Ji Ping

    2004-01-01

    The effect of irradiaiton preservation of frozen shelled shrimps for export was studied. The microbial indexd, nutritional ingredient, physico-chemical index for irradiation frozen shelled shrimps were detected. The results showed that 3-5 kGy irradiation dose could kill more than 99% of all kinds of microorganisms in frozen shelled shrimps, the content of most amino acids in shelled shrimps increased, after being irradiated by 1-9 kGy dose, the total amino acids had been obvisouly higher than CK, the increased range was 0.33%-24.6%, the content of the total volatile basic nitrogen (TVBN) decreased. Compared with the CK, the content of the heavy metal elements etc had no obvious change, the presrvation duration of irradiated shelled shrimp was twelve months longer than that of CK when storage temperature was under -7 degree C soft frozen, Compared with -18 degree C the effect of irradiation preservation had no obvious change. (authors)

  13. Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

    Science.gov (United States)

    Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao

    2017-01-01

    Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only. PMID:28691028

  14. Presentation of frozen shoulder among diabetic and non-diabetic patients☆

    Science.gov (United States)

    Uddin, Mohammad Moin; Khan, Aminuddin A.; Haig, Andrew J.; Uddin, Mohammad Kafil

    2014-01-01

    Objective The literature is inconsistent regarding the level of pain and disability in frozen shoulder patients with or without diabetes mellitus. The aim of this study is to evaluate some demographic features of frozen shoulder patients and to look into the disparity of information by comparing the level of pain and disability due to frozen shoulder between diabetic and non-diabetic people. Design This is a prospective comparative study. People with frozen shoulder attending an outpatient department were selected by consecutive sampling. Disability levels were assessed by the Shoulder Pain & Disability Index (SPADI). Means of pain and disability scores were compared using unpaired t-test. Results Among 140 persons with shoulder pain 99 (71.4%) had frozen shoulder. From the participating 40 frozen shoulder patients, 26 (65%) were males and 14 (35%) were females. Seventeen participants (42.5%) were diabetic, two (5%) had impaired glucose tolerance and 21 (52.5%) patients were non-diabetic. Mean disability scores (SPADI) were 51 ± 15.5 in diabetic and 57 ± 16 in non-diabetic persons. The differences in pain and disability level were not statistically significance (respectively, p = 0.24 and p = 0.13 at 95% confidence interval). Conclusions No difference was found in level of pain and disability level between frozen shoulder patients with and without diabetes. PMID:25983497

  15. Presentation of frozen shoulder among diabetic and non-diabetic patients.

    Science.gov (United States)

    Uddin, Mohammad Moin; Khan, Aminuddin A; Haig, Andrew J; Uddin, Mohammad Kafil

    2014-12-01

    The literature is inconsistent regarding the level of pain and disability in frozen shoulder patients with or without diabetes mellitus. The aim of this study is to evaluate some demographic features of frozen shoulder patients and to look into the disparity of information by comparing the level of pain and disability due to frozen shoulder between diabetic and non-diabetic people. This is a prospective comparative study. People with frozen shoulder attending an outpatient department were selected by consecutive sampling. Disability levels were assessed by the Shoulder Pain & Disability Index (SPADI). Means of pain and disability scores were compared using unpaired t-test. Among 140 persons with shoulder pain 99 (71.4%) had frozen shoulder. From the participating 40 frozen shoulder patients, 26 (65%) were males and 14 (35%) were females. Seventeen participants (42.5%) were diabetic, two (5%) had impaired glucose tolerance and 21 (52.5%) patients were non-diabetic. Mean disability scores (SPADI) were 51 ± 15.5 in diabetic and 57 ± 16 in non-diabetic persons. The differences in pain and disability level were not statistically significance (respectively, p = 0.24 and p = 0.13 at 95% confidence interval). No difference was found in level of pain and disability level between frozen shoulder patients with and without diabetes.

  16. Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

    Directory of Open Access Journals (Sweden)

    Amro Abdelazez

    2017-01-01

    Full Text Available Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548 were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044 for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

  17. Radiation resistivity of frozen insulin solutions and suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Soboleva, N N; Ivanova, A I; Talrose, V L; Trofimov, V I; Fedotov, V P [AN SSSR, Moscow. Inst. Fizicheskoj Khimii; Research Institute for Biological Testing of Chemicals, Moscow (USSR); Institute of Experimental Endocrinology and Hormon Chemistry, Moscow (USSR))

    1981-10-01

    The effect of great increase in radiation resistance of insulin solutions and suspensions after irradiation at low temperatures in the frozen state was observed by absorption spectrophotometry, paper chromatography and biological analysis. The data obtained suggest irradiation of frozen insulin solutions and suspensions as a method for its sterilization.

  18. Researches on the Constitutive Models of Artificial Frozen Silt in Underground Engineering

    Directory of Open Access Journals (Sweden)

    Yugui Yang

    2014-01-01

    Full Text Available The researches on the mechanical characteristic and constitutive models of frozen soil have important meanings in structural design of deep frozen soil wall. In the present study, the triaxial compression and creep tests have been carried out, and the mechanical characteristic of frozen silt is obtained. The experiment results show that the deformation characteristic of frozen silt is related to confining pressure under conventional triaxial compression condition. The frozen silt presents strain softening in shear process; with increase of confining pressure, the strain softening characteristic gradually decreases. The creep curves of frozen silt present the decaying and the stable creep stages under low stress level; however, under high stress level, once the strain increases to a critical value, the creep strain velocity gradually increases and the specimen quickly happens to destroy. To reproduce the deformation behavior, the disturbed state elastoplastic and new creep constitutive models of frozen silt are developed. The comparisons between experimental results and calculated results from constitutive models show that the proposed constitutive models could describe the conventional triaxial compression and creep deformation behaviors of frozen silt.

  19. 75 FR 22551 - United States Standards for Grades of Frozen Blueberries

    Science.gov (United States)

    2010-04-29

    ...] United States Standards for Grades of Frozen Blueberries AGENCY: Agricultural Marketing Service, USDA... United States Standards for Grades of Frozen Blueberries. After considering the comments received... . The United States Standards for Grades of Frozen Blueberries are available by accessing the AMS Web...

  20. Prevention of ligneous conjunctivitis by topical and subconjunctival fresh frozen plasma.

    Science.gov (United States)

    Tabbara, Khalid F

    2004-08-01

    To present a case of ligneous conjunctivitis where the recurrence of membranous conjunctivitis was prevented by subconjunctival and topical instillation of fresh frozen plasma. Interventional case report. A case of ligneous conjunctivitis with multiple recurrences since the age of 3 years developed recurrent membranous conjunctivitis after transconjunctival levator recession. Blood plasminogen activity was determined. The membrane was excised, and the membrane reappeared 4 days later. The patient was treated with excision of the membrane and subconjunctival injection of fresh frozen plasma and topical fresh frozen plasma. Plasminogen activity of the fresh frozen plasma was normal. Plasminogen blood functional activity was 52% (normal is 80%-120%). The patient had complete remission with no recurrences of membranous conjunctivitis after topical and subconjunctival fresh frozen plasma. Prophylactic use of topical and subconjunctival fresh frozen plasma may help in the prevention of membranes in susceptible patients with plasminogen deficiency.

  1. Stark effect in Rydberg states of helium and barium

    International Nuclear Information System (INIS)

    Lahaije, C.T.W.

    1989-01-01

    This thesis, which deals with the effect of an electric field up to moderate field strengths on atoms with two valence electrons outside closed shells, in casu helium and barium, contains chapter in which the linear Stark effect in the 1 snp 1, 3 p Rydberg states of helium (n around 40) has been studied in a CW laser-atomic beam experiment. The evolution of the angular momentum manifolds into the n-mixing regime was followed and avoided level crossings were observed. Stark manifolds were also calculated by diagonalization of the complete energy matrix in the presence of an electric field. It turned out to be necessary to include up to five n-values in the calculations already at moderate values of the field to reproduce the data within the experimental accuracy (a few MHz), especially in the regime of the avoided crossings. (author). 147 refs.; 30 figs.; 8 tabs

  2. Energy-level repulsion by spin-orbit coupling in two-dimensional Rydberg excitons

    Science.gov (United States)

    Stephanovich, V. A.; Sherman, E. Ya.; Zinner, N. T.; Marchukov, O. V.

    2018-05-01

    We study the effects of Rashba spin-orbit coupling on two-dimensional Rydberg exciton systems. Using analytical and numerical arguments we demonstrate that this coupling considerably modifies the wave functions and leads to a level repulsion that results in a deviation from the Poissonian statistics of the adjacent level distance distribution. This signifies the crossover to nonintegrability of the system and hints at the possibility of quantum chaos emerging. Such behavior strongly differs from the classical realization, where spin-orbit coupling produces highly entangled, chaotic electron trajectories in an exciton. We also calculate the oscillator strengths and show that randomization appears in the transitions between states with different total momenta.

  3. Effect of gamma-irradiation on frozen shrimps for decontamination of pathogenic bacteria

    Science.gov (United States)

    Ito, Hitoshi; Rashid, Harun Or; Sangthong, Naruemon; Adulyatham, Pitaya; Rattagool, Pongpen; Ishigaki, Isao

    1993-07-01

    Twelve samples of imported frozen shrimps were used in this study. The total aerobic bacteria were at 2 × 10 4 to 6 × 10 6 per gram. A few of Vibrio parahaemolyticus, V. mimicus, V. alginolyticus, V. vulnificus, V. fluvialis and Listeria monocytogenes were isolated from many samples. However, Salmonella was not detected in any of the samples. After exposure to 4-5 kGy of gamma-rays, the total aerobic bacteria in frozen shrimps were reduced by approximately 2-3 log cycles. The dose necessary to reduce the vibrio isolates and Aeromonas hydrophila at a level of below 10 -4 per gram was about 3 kGy in frozen shrimps, whereas about 3.5 kGy was required for L. monocytogenes and Salmonella typhimurium. In this study, unpleasant off-odor was clearly detected in the non-frozen shrimps irradiated at 2.5 kGy. On the other hand, off-odor was negligible in the frozen product below 5 kGy irradiation. No remarkable changes of peroxide values were also obtained up to 9 kGy of irradiation in the frozen shrimps. However peroxide values of non-frozen shrimps were clearly increased even irradiated at 4 kGy. Trimethylamine content was not changed at doses below 10 kGy in both of frozen and non-frozen shrimps. Shelf-life of defrosted shrimps were extended ca. 2 times under non-frozen market conditions.

  4. Rates of surgery for frozen shoulder: an experience in England.

    Science.gov (United States)

    Kwaees, Tariq A; Charalambous, Charalambos P

    2015-01-01

    the aim of this study was to identify the incidence of surgical treatment for frozen shoulder in a western population. patients included in this study all resided within a well-defined area in the North West of England, all had surgery for frozen shoulder over a 3-year period and were identified from theatre logbooks of two local hospitals. Cases having surgery for shoulder stiffness other than frozen shoulder were excluded. Local and national population size estimates were based on data obtained from the UK Office for National Statistics. 117 patients underwent surgery for frozen shoulder during the period examined; of these 101 had arthroscopic arthrolysis and 16 had manipulation under anaesthesia. The overall incidence of frozen shoulder surgery was calculated at 2.67 procedures per 10,000 general population per year, and at 7.55 for those aged 40-60. surgical intervention for frozen shoulder is common, estimated at over 14,180 cases per year in England. Given the variation in costs associated with arthroscopic arthrolysis and manipulation under anaesthesia, comparative studies of the cost effectiveness of the two procedures would be of great value. 2C (outcome research).

  5. Storage tests on irradiated deep-frozen chickens

    International Nuclear Information System (INIS)

    Gruenewald, T.

    1975-01-01

    Salmonellae infections in deep-frozen roasting chicken can be dealt with by ionising radiation as this process involves hardly any heating of the product. Deep-frozen chickens irradiated with doses up to 800 krad were stored at -30 0 C for two years and were regularly submitted to sensory tests. There was no significant difference in quality between the irradiated samples and the non-irradiated controls. (orig.) [de

  6. Low temperature electrochemistry at normal conductor/frozen electrolyte interface

    International Nuclear Information System (INIS)

    Borkowska, Z.; Stimming, U.

    1991-01-01

    The frozen electrolyte technique (FREECE = FRozen Electrolyte ElectroChEmistry) is based on the experimental result that frozen electrolytes are suitable for electrochemical studies. This technique has been used in our laboratory and also by others to investigate interfacial electrochemical behavior. An argument will be given as to why the FREECE technique is advantageous in a number of respects and what kind of electrolyte systems can be used. Reference is made to electrochemical results such as interfacial reactions and double layer properties. 26 refs

  7. Two-electron excitation to Rydberg levels in fast I6+ on hydrogen collisions

    International Nuclear Information System (INIS)

    Liao, C.; Hagmann, S.; Zouros, T.J.M.; Montenegro, E.C.; Toth, G.; Richard, P.; Grabbe, S.; Bhalla, C.P.

    1995-01-01

    The emission of electrons in the forward direction in collisions of 0.3 MeV/u I 6+ with H 2 has been studied, and strong autoionization peaks are observed on the shoulder of the cusp peak. The energies of these autoionization lines in the projectile rest frame are determined by high-resolution electron spectroscopy. Using the electron projectile final charge state coincidence technique, we probe different collision mechanisms, which create continuum electrons that are slow in the projectile rest frame. We conclude that the observed autoionization lines are due to two electron excitation to projectile Rydberg levels. (orig.)

  8. Rydberg states in a microwave field: regularity and chaos; Atomes de rydberg en champ micro-onde: regularite et chaos

    Energy Technology Data Exchange (ETDEWEB)

    Buchleitner, A

    1993-12-15

    We develop a theoretical formalism which provides a powerful tool for the detailed numerical analysis of the interaction of three-dimensional hydrogen atoms with an intense radiation field. The application of this approach to the microwave ionization of Rydberg states of hydrogen provides the most realistic numerical experiments ever made in this area. A thorough analysis of ionization signals and thresholds, of level dynamics and of the phase space projections of associated wave functions is provided for a one-dimensional model of the atom. The comparison to the ionization of three-dimensional atoms confirms the validity of the one-dimensional model for extended initial states and, hence, dynamical localization theory, as far as the ionization threshold is concerned. Three classes of three-dimensional initial states with distinct symmetries are identified and they appear to be more or less adapted to the symmetries of the eigenstates of the microwave problem. 'Scarred' wavefunctions of the three-dimensional hydrogen atom exposed to microwave field are shown. Finally, the dynamics of a circular state in a microwave and in an intense laser field are compared. (author)

  9. 7 CFR 58.318 - Butter, frozen or plastic cream melting machines.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Butter, frozen or plastic cream melting machines. 58... Service 1 Equipment and Utensils § 58.318 Butter, frozen or plastic cream melting machines. Shavers, shredders or melting machines used for rapid melting of butter, frozen or plastic cream shall be of...

  10. Lifetime measurements of highly excited Rydberg states of strontium. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Kunze, S.; Hohmann, R.; Kluge, H.J.; Lantzsch, J.; Monz, L.; Stenner, J.; Stratmann, K.; Wendt, K.; Zimmer, K. (Mainz Univ. (Germany). Inst. fuer Physik)

    1993-06-01

    Lifetimes of Rydberg states of triplet-series 5s ns[sup 3]S[sub 1] with n=19-23, 35 and 5s nd[sup 3]D[sub 3] with n=18-20, 23-28 in the spectrum of neutral strontium have been determined. Observation of the exponential decay after excitation by a pulsed laser in a fast atomic beam and subsequent state-selective field ionization was employed. The lifetimes of the states of the [sup 3]S[sub 1]-series show the expected n*[sup 3] dependence on the effective principal quantum number, while the [sup 3]D[sub 3]-series is disturbed by configuration mixing. Furthermore, state re-populations induced by black-body radiation have been observed. (orig.).

  11. Millimeter wave detection via Autler-Townes splitting in rubidium Rydberg atoms

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Joshua A., E-mail: josh.gordon@nist.gov; Holloway, Christopher L. [National Institute of Standards and Technology (NIST), Electromagnetics Division, U.S. Department of Commerce, Boulder Laboratories, Boulder, Colorado 80305 (United States); Schwarzkopf, Andrew; Anderson, Dave A.; Miller, Stephanie; Thaicharoen, Nithiwadee; Raithel, Georg [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-07-14

    In this paper, we demonstrate the detection of millimeter waves via Autler-Townes splitting in {sup 85}Rb Rydberg atoms. This method may provide an independent, atom-based, SI-traceable method for measuring mm-wave electric fields, which addresses a gap in current calibration techniques in the mm-wave regime. The electric-field amplitude within a rubidium vapor cell in the WR-10 wave guide band is measured for frequencies of 93.71 GHz and 104.77 GHz. Relevant aspects of Autler-Townes splitting originating from a four-level electromagnetically induced transparency scheme are discussed. We measured the E-field generated by an open-ended waveguide using this technique. Experimental results are compared to a full-wave finite element simulation.

  12. Semiclassical analysis of quantum localization of the periodically kicked Rydberg atom

    International Nuclear Information System (INIS)

    Yoshida, S.; Persson, E.; Burgdoerfer, J.; Grossmann, F.

    2004-01-01

    The periodically kicked Rydberg atom displays quantum localization, features of which depend on the orientation and strength of the unidirectional kicks. They include scarring of the wave function, localization by cantori, and exponential localization in the regime of strong perturbation resembling dynamical localization. Using the semiclassical Herman-Kluk propagator we investigate the degree to which semiclassical dynamics can mimic quantum localization. While the semiclassical approximation has difficulties to reproduce the scarred wave functions, the exponential tail which is a typical signature of the dynamical localization is well represented in the case of strong classical diffusion. Also the localization by broken tori is observed in the semiclassical recurrence probability for short times but the deviation from the corresponding quantum dynamics becomes more pronounced for the long-time evolution

  13. Calculation of the thermal conductivity of frozen foods

    International Nuclear Information System (INIS)

    Orrego A, C.E.

    1998-01-01

    A simple model is presented for the presage of the thermal conductivity of frozen foods those combines different authors' proposals. For varied materials on those that there is available information of the modification of this property with the temperature in frozen systems, the comparison of the dear and empiric values is made to evaluate these predictions

  14. Role of frozen section in surgery of benign thyroid

    Directory of Open Access Journals (Sweden)

    Tomaž Štupnik

    2007-04-01

    Full Text Available Background: Fine-needle aspiration biopsy can very reliably discriminate between benign and malignant thyroid tumors. The role of additional intraoperative frozen section to guide intraoperative management was questioned.Methods: A retrospective analysis of all thyroid resections at our department between 2000 and 2004 was performed.Results: 420 patients with benign thyroid lesions underwent surgical resections. 169 lobectomies and 251 total thyroidectomies were performed and 57 (13.5 % thyroid cancers discovered (mostly papillary carcinomas. 54 frozen sections were performed and sensitivity rate of 11.1 % and specificity rate of 97.8 % was estimated.Conclusions: Our data supports the fact that intraoperative frozen section is not sensitive enough to substantially add to preoperative fine-needle aspiration biopsy, even with more selective use. We conclude that routine use of frozen section is not cost-effective in surgery of the benign thyroid and can therefore be abandoned.

  15. Dynamical localization in the 3-D kicked Rydberg atom

    International Nuclear Information System (INIS)

    Persson, E.; Yoshida, S.; Tong, X.-M.; Reinhold, C.; Burgdoerfer, J.

    2001-01-01

    Full text: The dynamical localization for the 3D periodically kicked Rydberg atom is analyzed. For the 1D kicked atom, earlier work shows dynamical localization as the quantum suppression of classically fast ionization associated with unbounded chaotic trajectories. The corresponding wave functions localize around unstable periodic orbits. For the experimental observation, the crucial question is the dependence of the dynamical localization on the dimension. As the first step, we simulate the full 3D evolution of an extreme parabolic initial state elongated in the direction of the unidirectional kicks. We compare this simulation with the 1D model and find signatures of localization also in 3D. We further examine the dependence of quantum localization on the parabolic quantum number of the initial state. In the limit of high kick frequencies, the origin of the localization can be understood in terms of Stark states in the average field. We discuss conditions for where an experimental observation of the localization is most likely. (author)

  16. 40 CFR 407.40 - Applicability; description of the frozen potato products subcategory.

    Science.gov (United States)

    2010-07-01

    ... frozen potato products subcategory. 407.40 Section 407.40 Protection of Environment ENVIRONMENTAL... PROCESSING POINT SOURCE CATEGORY Frozen Potato Products Subcategory § 407.40 Applicability; description of the frozen potato products subcategory. The provisions of this subpart are applicable to discharges...

  17. Aspects of three field approximations: Darwin, frozen, EMPULSE

    International Nuclear Information System (INIS)

    Boyd, J.K.; Lee, E.P.; Yu, S.S.

    1985-01-01

    The traditional approach used to study high energy beam propagation relies on the frozen field approximation. A minor modification of the frozen field approximation yields the set of equations applied to the analysis of the hose instability. These models are constrasted with the Darwin field approximation. A statement is made of the Darwin model equations relevant to the analysis of the hose instability

  18. Coherent Microwave-to-Optical Conversion via Six-Wave Mixing in Rydberg Atoms

    Science.gov (United States)

    Han, Jingshan; Vogt, Thibault; Gross, Christian; Jaksch, Dieter; Kiffner, Martin; Li, Wenhui

    2018-03-01

    We present an experimental demonstration of converting a microwave field to an optical field via frequency mixing in a cloud of cold 87Rb atoms, where the microwave field strongly couples to an electric dipole transition between Rydberg states. We show that the conversion allows the phase information of the microwave field to be coherently transferred to the optical field. With the current energy level scheme and experimental geometry, we achieve a photon-conversion efficiency of ˜0.3 % at low microwave intensities and a broad conversion bandwidth of more than 4 MHz. Theoretical simulations agree well with the experimental data, and they indicate that near-unit efficiency is possible in future experiments.

  19. Cytochrome oxidase as an indicator of ice storage and frozen storage

    DEFF Research Database (Denmark)

    Godiksen, Helene; Jessen, Flemming

    2001-01-01

    in different cods was 21%, and the coefficient of variation of different analyses on the same homogenate was 5%. It was shown that ice storage of muscle samples before they were frozen and thawed resulted in a major freezing-induced activation of cytochrome oxidase activity. The enzyme may therefore be used...... as an indicator of frozen fish to determine if the fish has been stored on ice before freezing. Cytochrome oxidase activity showed also potential as an indicator of frozen storage, as it was possible to distinguish between the frozen storage temperatures -9, -20, and -40 degreesC....

  20. Cooking frozen and thawed roasts: beef, pork, and lamb cuts.

    Science.gov (United States)

    Fulton, C; Davis, C

    1975-09-01

    Cooking time, yield, and palatability of paired beef, pork, and lamb roasts cooked from the frozen and thawed states were compared. Cooking time for all roasts averaged from 3 to 22 min. per pound longer for meat cooked from the frozen state. The longer cooking time from the frozen state. The longer cooking time from the frozen state was greater for roasts with a large amount of bone and for cuts cooked by braising than for less bony roasts and cuts cooked by roasting. Except for thawed beef rump roasts, which had a higher yield of cooked lean meat, yield of cooked lean meat from the various cuts of beef, pork, and lamb was not affected by the state at the start of cooking. Collectively, all pork roasts had a higher yield of cooked lean meat when cooked from the frozen state. Juiciness and natural flavor of the roasts were not affected by the state at the start of cooking. Lamb leg and rib roasts were more tender when cooked from the thawed state.

  1. Shipping trial of irradiated frozen shrimp from Thailand to the Netherlands

    International Nuclear Information System (INIS)

    Prachasitthisak, Y.; Nouchpramool, K.; Charoen, S.; Adulyatham, P.; Williams, J.L.; Stegeman, H.; Farkas, J.

    1988-01-01

    Quality of non-irradiated and irradiated frozen shrimp after shipping trial from Thailand to the Netherlands were investigated. Commercial frozen shell on headless shrimp and pre-cooked and peeled shrimp were irradiated with 0, 2, and 3 kGy at the Office of Atomic Energy for Peace (OAEP), Thailand, and transported by sea to the International Facility for Food Irradiation Technology (IFFIT), the Netherlands. It was found that both types of frozen shrimp before shipment are of good quality. Radiation with 3 kGy resulted in 2-3 log cycles reduction of mesophilic and psychrotrophic colony counts and caused no significant change in sensory quality. The irradiated products were found to be free from coliforms, faecal coliforms, Escherichia coli, salmonella, vibrio parahaemolyticus and Staphylococcus aureus. There was no increase in bacterial count in irradiated frozen shrimps after two months of transportation. The results of flora analysis show that radiation does not present any hazard resulting from a shift in the microflora. The surviving microflora in both types of irradiated frozen shrimp consisted mainly of Micrococcus spp.. Besides, irradiation with dose of 3 kGy did not affect the sensory quality of the frozen shrimp within duration of transportation. It can be concluded that irradiation improves the bacteriological quality of frozen shrimp for transportation to the Netherlands

  2. Frozen assets

    Energy Technology Data Exchange (ETDEWEB)

    1988-12-02

    In June this year, delegates from more than 30 Antarctic Treaty nations met and agreed on a set of rules under the 'Convention on the Regulation of Antartic Mineral Resource Activities'. The convention presents a legal basis for mining which previously did not exist but it requires the two-third approval of a regulatory committee comprising countries both with and without territorial claims. However, the environment of the Antarctic is so harsh that very few in the international mining industry consider mining in the frozen continent a viable proposition.

  3. Cryogenic freezing of fresh date fruits for quality preservation during frozen storage

    Directory of Open Access Journals (Sweden)

    Abdullah Alhamdan

    2018-01-01

    Full Text Available Fresh date fruits, especially Barhi cultivar, are favored and widely consumed at the Khalal maturity stage (first color edible stage. These fruits are seasonal and perishable and there is a need for extending their shelf life. This study evaluates two different freezing methods, namely cryogenic freezing using liquid nitrogen and conventional deep freezing on preserving the quality and stability of date fruits (cv. Barhi at Khalal maturity stage. Fresh date fruits (cv. Barhi at Khalal stage were frozen utilizing the two methods. The produced frozen dates were stored under frozen storage conditions for nine months (at −20 °C and −40 °C for the conventional and cryogenic freezing, respectively. Color values, textural properties (hardness, elasticity, chewiness and resilience, and nutrition attributes (enzymes and sugars for fresh dates before freezing and for the frozen dates were measured every three months during the frozen storage. Color values of the frozen dates were affected by the freezing method and the frozen storage period. There are substantial differences in the quality of the frozen fruits in favor of cryogenic freezing compared to the conventional slow freezing. The results revealed a large disparity between the times of freezing of the two methods. The freezing time accounted to 10 min in the cryogenic freezing method, whereas it was 1800 min for the conventional slow freezing system.

  4. Semiclassical study of the collision of a highly excited Rydberg atom with the molecules HF and HCl

    International Nuclear Information System (INIS)

    Kimura, M.; Lane, N.F.

    1990-01-01

    The semiclassical impact-parameter method is applied to the processes of state changing and energy transfer in the collision of a highly excited Rydberg atom (n≥20) with the polar molecules HF and HCl. The relative motion of the molecule and atomic nucleus is taken to be rectilinear; the electron-molecule and ion core-molecule interactions are represented by cutoff dipole forms. Cross sections for transitions involving quantum numbers n and l of the atom and rotational quantum number j of the molecule are obtained for a range of collision energies and initial atomic and molecular states. Comparisons are made with the results of earlier classical studies and with the quantum-mechanical impulse approximation. Collision rates are calculated and compared with experimental values for l mixing and n and j changing. The agreement between experiment and theory is shown to be satisfactory, within the uncertainties of both the measurements and the theory. Cases of agreement and disagreement between various theories are examined. One finding of the present work is that the quantum-mechanical impulse approximation appears to significantly overestimate the values of various state-changing cross sections when the internal energy defect is small. The validity of the impulse approximation for collisions of Rydberg atoms with polar molecules is discussed

  5. The role of Rydberg and continuum levels in computing high harmonic generation spectra of the hydrogen atom using time-dependent configuration interaction

    International Nuclear Information System (INIS)

    Luppi, Eleonora; Head-Gordon, Martin

    2013-01-01

    We study the role of Rydberg bound-states and continuum levels in the field-induced electronic dynamics associated with the High-Harmonic Generation (HHG) spectroscopy of the hydrogen atom. Time-dependent configuration-interaction (TD-CI) is used with very large atomic orbital (AO) expansions (up to L= 4 with sextuple augmentation and off-center functions) to describe the bound Rydberg levels, and some continuum levels. To address the lack of ionization losses in TD-CI with finite AO basis sets, we employed a heuristic lifetime for energy levels above the ionization potential. The heuristic lifetime model is compared against the conventional atomic orbital treatment (infinite lifetimes), and a third approximation which is TD-CI using only the bound levels (continuum lifetimes go to zero). The results suggest that spectra calculated using conventional TD-CI do not converge with increasing AO basis set size, while the zero lifetime and heuristic lifetime models converge to qualitatively similar spectra, with implications for how best to apply bound state electronic structure methods to simulate HHG. The origin of HHG spectral features including the cutoff and extent of interference between peaks is uncovered by separating field-induced coupling between different types of levels (ground state, bound Rydberg levels, and continuum) in the simulated electronic dynamics. Thus the origin of deviations between the predictions of the semi-classical three step model and the full simulation can be associated with particular physical contributions, which helps to explain both the successes and the limitations of the three step model

  6. Yeasts associated with fresh and frozen pulps of Brazilian tropical fruits.

    Science.gov (United States)

    Trindade, Rita C; Resende, Maria Aparecida; Silva, Claudia M; Rosa, Carlos A

    2002-08-01

    The occurrence of yeasts on ripe fruits and frozen pulps of pitanga (Eugenia uniflora L), mangaba (Hancornia speciosa Gom.), umbu (Spondias tuberosa Avr. Cam.), and acerola (Malpighia glaba L) was verified. The incidence of proteolytic, pectinolytic, and mycocinogenic yeasts on these communities was also determined. A total of 480 colonies was isolated and grouped in 405 different strains. These corresponded to 42 ascomycetous and 28 basidiomycetous species. Candida sorbosivorans, Pseudozyma antarctica, C. spandovensis-like, C. spandovensis, Kloeckera apis, C. parapsilosis, Rhodotorula graminis, Kluyveromyces marxianus, Cryptococcus laurentii, Metchnikowia sp (isolated only from pitanga ripe fruits), Issatchenkia occidentalis and C. krusei (isolated only from mangaba frozen pulps), were the most frequent species. The yeast communities from pitanga ripe fruits exhibited the highest frequency of species, followed by communities from acerola ripe fruits and mangaba frozen pulps. Yeast communities from frozen pulp and ripe fruits of umbu had the lowest number of species. Except the yeasts from pitanga, yeast communities from frozen pulp exhibited higher number of yeasts than ripe fruit communities. Mycocinogenic yeasts were found in all of the substrates studied except in communities from umbu ripe fruits and pitanga frozen pulps. Most of the yeasts found to produce mycocins were basidiomycetes and included P. antarctica, Cryptococcus albidus, C. bhutanensis-like, R. graminis and R. mucilaginosa-like from pitanga ripe fruits as well as black yeasts from pitanga and acerola ripe fruits. The umbu frozen pulps community had the highest frequency of proteolytic species. Yeasts able to hydrolyse casein at pH 5.0 represented 38.5% of the species isolated. Thirty-seven percent of yeast isolates were able to hydrolyse casein at pH 7.0. Pectinolytic yeasts were found in all of the communities studied, excepted for those of umbu frozen pulps. The highest frequency of

  7. Phase diagram of Rydberg atoms with repulsive van der Waals interaction

    International Nuclear Information System (INIS)

    Osychenko, O. N.; Astrakharchik, G. E.; Boronat, J.; Lutsyshyn, Y.; Lozovik, Yu. E.

    2011-01-01

    We report a quantum Monte Carlo calculation of the phase diagram of bosons interacting with a repulsive inverse sixth power pair potential, a model for assemblies of Rydberg atoms in the local van der Waals blockade regime. The model can be parametrized in terms of just two parameters, the reduced density and temperature. Solidification happens to the fcc phase. At zero temperature, the transition density is found with the diffusion Monte Carlo method at density ρ=3.9 ((ℎ/2π) 2 /mC 6 ) 3/4 , where C 6 is the strength of the interaction. The solidification curve at nonzero temperature is studied with the path-integral Monte Carlo approach and is compared with transitions in corresponding harmonic and classical crystals. Relaxation mechanisms are considered in relation to present experiments.

  8. Study of process frozen dough of steamed bread added black rice

    International Nuclear Information System (INIS)

    Liu Shuang; Wang Chonglin

    2014-01-01

    The aim of the present work is to extent the storage period of wheat steamed bread added black rice. Based on index of sensory evaluation steamed bread. Effects of the use of film, Effects of electron beam irradiation on processing characteristics of wheat flour, yeast content, fermentation time before frozen, second fermentation time before steaming, combination of differerent additives on bread properties of frozen dough were investigate. The result showed that: the best frozen dough recipe were film processing, l% yeast, 1 h fermentation time before frozen , 45 min second fermentation time before steaming, 0.075% CMC, O.21 % Vc, 0.35% GMS. (authors)

  9. Ionization photophysics and Rydberg spectroscopy of diacetylene

    KAUST Repository

    Schwell, Martin

    2012-11-01

    Photoionization of diacetylene was studied using synchrotron radiation over the range 8-24 eV, with photoelectron-photoion coincidence (PEPICO) and threshold photoelectron-photoion coincidence (TPEPICO) techniques. Mass spectra, ion yields, total and partial ionization cross-sections were measured. The adiabatic ionization energy of diacetylene was determined as IE ad=(10.17±0.01) eV, and the appearance energy of the principal fragment ion C4H+ as AE=(16.15±0.03) eV. Calculated appearance energies of other fragment ions were used to infer aspects of dissociation pathways forming the weaker fragment ions C+ 4, C3H+, C+3 and C 4H+. Structured autoionization features observed in the PEPICO spectrum of diacetylene in the 11-13 eV region were assigned to vibrational components of three new Rydberg series, R1(nsσg, n=4-11), R2(ndσg, n=4-7) and R3(ndδg, n=4-6) converging to the A2Πu state of the cation, and to a new series R01(nsσg, n=3) converging to the B\\' 2Σ+u state of the cation. The autoionization mechanisms and their consistence with specific selection rules are discussed. © 2012 Taylor and Francis.

  10. Ionization photophysics and Rydberg spectroscopy of diacetylene

    KAUST Repository

    Schwell, Martin; Bé nilan, Yves; Fray, Nicolas; Gazeau, Marie Claire; Es-sebbar, Et-touhami; Gaie-Levrel, Franç ois; Champion, Norbert; Leach, Sydney Sydney

    2012-01-01

    Photoionization of diacetylene was studied using synchrotron radiation over the range 8-24 eV, with photoelectron-photoion coincidence (PEPICO) and threshold photoelectron-photoion coincidence (TPEPICO) techniques. Mass spectra, ion yields, total and partial ionization cross-sections were measured. The adiabatic ionization energy of diacetylene was determined as IE ad=(10.17±0.01) eV, and the appearance energy of the principal fragment ion C4H+ as AE=(16.15±0.03) eV. Calculated appearance energies of other fragment ions were used to infer aspects of dissociation pathways forming the weaker fragment ions C+ 4, C3H+, C+3 and C 4H+. Structured autoionization features observed in the PEPICO spectrum of diacetylene in the 11-13 eV region were assigned to vibrational components of three new Rydberg series, R1(nsσg, n=4-11), R2(ndσg, n=4-7) and R3(ndδg, n=4-6) converging to the A2Πu state of the cation, and to a new series R01(nsσg, n=3) converging to the B' 2Σ+u state of the cation. The autoionization mechanisms and their consistence with specific selection rules are discussed. © 2012 Taylor and Francis.

  11. Assessment of frozen storage duration effect on quality characteristics of various horse muscles

    Directory of Open Access Journals (Sweden)

    Pil Nam Seong

    2017-12-01

    Full Text Available Objective The study aimed at assessing the effects of frozen storage duration on quality characteristics, lipid oxidation and sensory quality of various horse muscles. Methods Five representative muscles: longissimus dorsi (LD, gluteus medius (GM, semimembranosus (SM, biceps femoris (BF, and triceps brachii (TB at 24 h post-mortem obtained from 28-mo-old Jeju female breed horses (n = 8 were used in the present investigation. The muscles were vacuum-packaged and frozen at −20°C for 120, 240, and 360 days. All the samples were analyzed for thawing and cooking losses, pH, Warner–Bratzler shear forces (WBSF, color traits, total volatile basic nitrogen (TVBN, thiobarbituric acid reactive substances (TBARS and sensory traits. The muscle samples analyzed on day 0 of frozen storage (fresh, non-frozen were used for comparison. Results Results revealed that thawing and cooking losses significantly (p<0.05 increased in all the muscles after 120 days and then remained unchanged up to 360 days of frozen storage. The TBARS and TVBN contents significantly increased as increasing frozen storage time up to 360 days (p<0.05. While, significant decreases in WBSF values were observed for all the muscles with increased frozen storage time (p<0.05. Frozen storage variously affected the color traits of the muscles for instance; the redness of LD, GM, and BF muscles showed a decreasing tendency during frozen storage while it was not changed in TB and SM muscles. Furthermore, the frozen storage did not produce detrimental effects on sensory quality as it did not cause flavor and juiciness defects whereas it partially improved the tenderness of all the muscles studied. Conclusion Based on the results obtained from our work, it is concluded that frozen storage could be applied to increase the long-term shelf life of horsemeat while still retaining its sensory quality.

  12. Marketing functions and determinants of profit among frozen chicken ...

    African Journals Online (AJOL)

    This study attempted to estimate the cost of performing some functions in frozen chicken marketing and determined the major factors affecting the profit level of the marketers. Using data collected from 10 wholesalers and 29 retailers in Ibadan metropolis, the transportation costs per kilogram of frozen chicken were N1.20 ...

  13. Association between Propionibacterium acnes and frozen shoulder: a pilot study.

    Science.gov (United States)

    Bunker, Tim D; Boyd, Matthew; Gallacher, Sian; Auckland, Cressida R; Kitson, Jeff; Smith, Chris D

    2014-10-01

    Frozen shoulder has not previously been shown to be associated with infection. The present study set out to confirm the null hypothesis that there is no relationship between infection and frozen shoulder using two modern scientific methods, extended culture and polymerase chain reaction (PCR) for bacterial nucleic acids. A prospective cohort of 10 patients undergoing arthroscopic release for stage II idiopathic frozen shoulder had two biopsies of tissue taken from the affected shoulder joint capsule at the time of surgery, along with control biopsies of subdermal fat. The biopsies and controls were examined with extended culture and PCR for microbial nucleic acid. Eight of the 10 patients had positive findings on extended culture in their shoulder capsule and, in six of these, Propionibacterium acnes was present. The findings mean that we must reject the null hypothesis that there is no relationship between infection and frozen shoulder. More studies are urgently needed to confirm or refute these findings. If they are confirmed, this could potentially lead to new and effective treatments for this common, painful and disabling condition. Could P. acnes be the Helicobacter of frozen shoulder?

  14. Positronium in the AEgIS experiment: study on its emission from nanochanneled samples and design of a new apparatus for Rydberg excitations

    CERN Document Server

    Di Noto, Lea

    This experimental thesis has been done in the framework of AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy), an experiment installed at CERN, whose primary goal is the measurement of the Earth's gravitational acceleration on anti-hydrogen. The antiatoms will be produced by the charge exchange reaction, where a cloud of Ps in Rydberg states interacts with cooled trapped antiprotons. Since the charge exchange cross section depends on Ps velocity and quantum number, the velocity distribution of Ps emitted by a positron-positronium converter as well as its excitation in Rydberg states have to be studied and optimized. In this thesis Ps cooling and emission into vacuum from nanochannelled silicon targets was studied by performing Time of Flight measurements with a dedicated apparatus conceived to receive the slow positron beam as produced at the Trento laboratory or at the NEPOMUC facility at Munich. Measurements were done by varying the positron implantation energy, the sample temperature and ...

  15. 75 FR 76754 - Non-Frozen Apple Juice Concentrate From China

    Science.gov (United States)

    2010-12-09

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-841 (Second Review)] Non-Frozen Apple Juice Concentrate From China AGENCY: United States International Trade Commission. ACTION: Termination... whether revocation of the antidumping duty order on non- frozen apple juice concentrate from China would...

  16. Semi-classical description of Rydberg atoms in strong, single-cycle electromagnetic pulses

    International Nuclear Information System (INIS)

    Jensen, R.V.; Sanders, M.M.

    1993-01-01

    Recent experimental measurements of the excitation and ionization of Rydberg atoms by single-cycle, electromagnetic pulses have revealed a variety of novel features. Because many quantum states are strongly coupled by the broadband radiation in the short pulse, the traditional methods of quantum mechanics are inadequate to account for the experimental results. We have therefore developed a semi-classical description of the interaction of both hydrogenic and non-hydrogenic atoms with single-cycle pulses of intense, electromagnetic radiation which is based on the strong correspondence theory of Percival and Richards. This theory, which was originally introduced for the description of strong atomic collisions, accounts for some of the surprising features of the experimental measurements and provides new predictions for future experimental studies

  17. An internal superconducting ''holding-coil'' for frozen spin targets

    International Nuclear Information System (INIS)

    Dutz, H.; Gehring, R.; Goertz, S.; Kraemer, D.; Meyer, W.; Reicherz, G.; Thomas, A.

    1995-01-01

    A new concept of a small superconducting holding magnet, placed inside a polarizing refrigerator, has been developed for frozen spin targets. The superconducting wire has been wound on the inner cooling shield of the vertical dilution refrigerator of the Bonn frozen spin target. The maximum field of the magnet is 0.35 T. The total thickness of the superconducting coil consisting of the wire and the copper carrier is of the order of 500 μm. Based on this concept, a frozen spin target is under construction for the measurement of the Gerasimov-Drell-Hearn sum rule with polarized real photons at the Mainz microtron MAMI and the Bonn electron stretcher accelerator ELSA. ((orig.))

  18. An internal superconducting ``holding-coil`` for frozen spin targets

    Energy Technology Data Exchange (ETDEWEB)

    Dutz, H. [Bonn Univ. (Germany). Physikalisches Inst.; Gehring, R. [Bonn Univ. (Germany). Physikalisches Inst.; Goertz, S. [Bonn Univ. (Germany). Physikalisches Inst.; Kraemer, D. [Bonn Univ. (Germany). Physikalisches Inst.; Meyer, W. [Bonn Univ. (Germany). Physikalisches Inst.; Reicherz, G. [Bonn Univ. (Germany). Physikalisches Inst.; Thomas, A. [Bonn Univ. (Germany). Physikalisches Inst.

    1995-03-01

    A new concept of a small superconducting holding magnet, placed inside a polarizing refrigerator, has been developed for frozen spin targets. The superconducting wire has been wound on the inner cooling shield of the vertical dilution refrigerator of the Bonn frozen spin target. The maximum field of the magnet is 0.35 T. The total thickness of the superconducting coil consisting of the wire and the copper carrier is of the order of 500 {mu}m. Based on this concept, a frozen spin target is under construction for the measurement of the Gerasimov-Drell-Hearn sum rule with polarized real photons at the Mainz microtron MAMI and the Bonn electron stretcher accelerator ELSA. ((orig.))

  19. Distribution of bacteria in frozen shrimps and their decontamination by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Adulyatham, P.; Ishigaki, Isao

    1987-11-01

    Six samples of frozen shrimps were obtained through importing company mainly from South-east Asian countries. Five samples of frozen shrimps contained 1.5 x 10/sup 5/ to 6.2 x 10/sup 6/ per gram of total aerobic bacteria, and 4 samples contained 1.4 x 10/sup 2/ to 2.2 x 10/sup 3/ per gram of coliforms, which are higher contamination than Japanese standard of hygenic level for frozen food products (total counts below 10/sup 5/ per gram and no coliforms). The dominant bacteria in total counts were consisted with psychrotrophic Moraxella, Arthrobacter, Micrococcus, Acinetobacter, Flavobacterium, Corynebacterium, Pseudomonas and etc, in all kinds of frozen shrimps. Salmonellae or enteric Vibrio were could not isolated by ordinary isolation methods, and there were isolated many strains of Proteus mirabilis instead of these bacteria. Necessary dose of gamma irradiation for decontamination of bacteria to hygenic level was decided as 3 approx. 5 kGy from the inactivation curves of total bacteria, coliforms, Proteus mirabilis and Salmonella typhymurium in frozen shrimps. Off-odor was suppressed by frozen condition of irradiation.

  20. Distribution of bacteria in frozen shrimps and their decontamination by gamma irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Adulyatham, P.; Ishigaki, Isao

    1987-01-01

    Six samples of frozen shrimps were obtained through importing company mainly from South-east Asian countries. Five samples of frozen shrimps contained 1.5 x 10 5 to 6.2 x 10 6 per gram of total aerobic bacteria, and 4 samples contained 1.4 x 10 2 to 2.2 x 10 3 per gram of coliforms, which are higher contamination than Japanese standard of hygenic level for frozen food products (total counts below 10 5 per gram and no coliforms). The dominant bacteria in total counts were consisted with psychrotrophic Moraxella, Arthrobacter, Micrococcus, Acinetobacter, Flavobacterium, Corynebacterium, Pseudomonas and etc, in all kinds of frozen shrimps. Salmonellae or enteric Vibrio were could not isolated by ordinary isolation methods, and there were isolated many strains of Proteus mirabilis instead of these bacteria. Necessary dose of gamma irradiation for decontamination of bacteria to hygenic level was decided as 3 ∼ 5 kGy from the inactivation curves of total bacteria, coliforms, Proteus mirabilis and Salmonella typhymurium in frozen shrimps. Off-odor was suppressed by frozen condition of irradiation. (author)

  1. 21 CFR 135.110 - Ice cream and frozen custard.

    Science.gov (United States)

    2010-04-01

    ...) of this section, the name of the food is “frozen custard” or “french ice cream” or “french custard... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Ice cream and frozen custard. 135.110 Section 135.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED...

  2. Asymptotically exact expression for the energies of the 3Se Rydberg series in a two-electron system

    International Nuclear Information System (INIS)

    Ivanov, I.A.; Bromley, M.W.J.; Mitroy, J.

    2002-01-01

    The 1sns 3 S e Rydberg series in a two-electron system with the charge of the nucleus, Z≅1, is treated by means of the quantum-defect theory. Comparison with configuration interaction calculations suggests that the quantum-defect expression for the energy levels becomes asymptotically exact as Z→1. This provides an analytic description of the disappearance of the 1sns 3 S e bound states when Z approaches the critical value of 1

  3. A Controlled-Phase Gate via Adiabatic Rydberg Dressing of Neutral Atoms

    Science.gov (United States)

    Keating, Tyler; Deutsch, Ivan; Cook, Robert; Biederman, Grant; Jau, Yuan-Yu

    2014-05-01

    The dipole blockade effect between Rydberg atoms is a promising tool for quantum information processing in neutral atoms. So far, most efforts to perform a quantum logic gate with this effect have used resonant laser pulses to excite the atoms, which makes the system particularly susceptible to decoherence through thermal motional effects. We explore an alternative scheme in which the atomic ground states are adiabatically ``dressed'' by turning on an off-resonant laser. We analyze the implementation of a CPHASE gate using this mechanism and find that fidelities of >99% should be possible with current technology, owing primarily to the suppression of motional errors. We also discuss how such a scheme could be generalized to perform more complicated, multi-qubit gates; in particular, a simple generalization would allow us to perform a Toffoli gate in a single step.

  4. Rydberg states in a microwave field: regularity and chaos

    International Nuclear Information System (INIS)

    Buchleitner, A.

    1993-12-01

    We develop a theoretical formalism which provides a powerful tool for the detailed numerical analysis of the interaction of three-dimensional hydrogen atoms with an intense radiation field. The application of this approach to the microwave ionization of Rydberg states of hydrogen provides the most realistic numerical experiments ever made in this area. A thorough analysis of ionization signals and thresholds, of level dynamics and of the phase space projections of associated wave functions is provided for a one-dimensional model of the atom. The comparison to the ionization of three-dimensional atoms confirms the validity of the one-dimensional model for extended initial states and, hence, dynamical localization theory, as far as the ionization threshold is concerned. Three classes of three-dimensional initial states with distinct symmetries are identified and they appear to be more or less adapted to the symmetries of the eigenstates of the microwave problem. 'Scarred' wavefunctions of the three-dimensional hydrogen atom exposed to microwave field are shown. Finally, the dynamics of a circular state in a microwave and in an intense laser field are compared. (author)

  5. Electromagnetically induced transparency in thermal Rydberg atoms: superatom model with finite Doppler broadening

    Science.gov (United States)

    Bai, Si-Yin; Bao, Qian-Qian; Tian, Xue-Dong; Liu, Yi-Mou; Wu, Jin-Hui

    2018-04-01

    We study the steady optical responses of a cold atomic ensemble driven into the three-level ladder configuration involving a Rydberg state at finite temperatures. By improving the superatom model with thermal movement included, we calculate relevant atomic coherence effects and find that the residual Doppler broadening at the mK-K temperatures will weaken the nonclassical properties of transmitted probe photons. Furthermore, propagation directions of the probe and coupling fields have a great influence on various properties related to electromagnetically induced transparency. That is, the residual Doppler effect is more destructive to relevant atomic coherence effects in the co-propagation case but can be partially eliminated in the counter-propagation case.

  6. Experimental Analysis and Discussion on the Damage Variable of Frozen Loess

    Directory of Open Access Journals (Sweden)

    Cong Cai

    2017-01-01

    Full Text Available The damage variable is very important to study damage evolution of material. Taking frozen loess as an example, a series of triaxial compression and triaxial loading-unloading tests are performed under five strain rates of 5.0 × 10−6–1.3 × 10−2/s at a temperature of −6°C. A damage criterion of frozen loess is defined and a damage factor Dc is introduced to satisfy the requirements of the engineering application. The damage variable of frozen loess is investigated using the following four methods: the stiffness degradation method, the deformation increase method, the dissipated energy increase method, and the constitutive model deducing method during deformation process. In addition, the advantages and disadvantages of the four methods are discussed when they are used for frozen loess material. According to the discussion, the plastic strain may be the most appropriate variable to characterize the damage evolution of frozen loess during the deformation process based on the material properties and the nature of the material service.

  7. The biochemical textural and sensory properties of frozen stored ...

    African Journals Online (AJOL)

    Post-rigor king scallop meats (Pecten maximus) were frozen individually for 24 h at -80°C and kept vacuum packed at -22°C for up to 301 days. Sampling was carried out on fresh meats and at days 1, 28, 91, 154, 210 and 301 of frozen storage. Tests related to muscle integrity ( -hydroxy-acyl-coenzyme –A dehydrogenase ...

  8. Stiffness Evolution in Frozen Sands Subjected to Stress Changes

    KAUST Repository

    Dai, Sheng; Santamarina, Carlos

    2017-01-01

    Sampling affects all soils, including frozen soils and hydrate-bearing sediments. The authors monitor the stiffness evolution of frozen sands subjected to various temperature and stress conditions using an oedometer cell instrumented with P-wave transducers. Experimental results show the stress-dependent stiffness of freshly remolded sands, the dominant stiffening effect of ice, creep after unloading, and the associated exponential decrease in stiffness with time. The characteristic time for stiffness loss during creep is of the order of tens of minutes; therefore it is inevitable that frozen soils experience sampling disturbances attributable to unloading. Slow unloading minimizes stiffness loss; conversely, fast unloading causes a pronounced reduction in stiffness probably attributable to the brittle failure of ice or ice-mineral bonding.

  9. Stiffness Evolution in Frozen Sands Subjected to Stress Changes

    KAUST Repository

    Dai, Sheng

    2017-04-21

    Sampling affects all soils, including frozen soils and hydrate-bearing sediments. The authors monitor the stiffness evolution of frozen sands subjected to various temperature and stress conditions using an oedometer cell instrumented with P-wave transducers. Experimental results show the stress-dependent stiffness of freshly remolded sands, the dominant stiffening effect of ice, creep after unloading, and the associated exponential decrease in stiffness with time. The characteristic time for stiffness loss during creep is of the order of tens of minutes; therefore it is inevitable that frozen soils experience sampling disturbances attributable to unloading. Slow unloading minimizes stiffness loss; conversely, fast unloading causes a pronounced reduction in stiffness probably attributable to the brittle failure of ice or ice-mineral bonding.

  10. Chemical Changes of Short-Bodied Mackerel (Rastrelliger Brachysoma) Muscle at Chilled and Frozen Storage

    International Nuclear Information System (INIS)

    Emilia Azrina Mohd Bakri; Norizzah Abd Rashid; Seng, C.C.; Anida Yusoff; Fazilah Fazilin Juhari

    2016-01-01

    This study was carried out to evaluate the chemical changes in short-bodied mackerel during chilled (4 degree Celcius) and frozen (-18 degree Celicus) storage for 18 days. The chemical changes were monitored at three days interval using Peroxide Value (PV), Thiobarbituric Acid (TBA), Total Volatile Base Nitrogen (TVBN) and Trimethylamine (TMA) tests. The PV of both chilled and frozen mackerel significantly increased (p<0.05) with storage time and the rate was significantly higher in chilled than frozen mackerel. Based on the results, the chilled and frozen mackerel started to become rancid at day 15 and day 18, respectively. Similar trend was observed for TBA value, where the malonaldehyde content significantly increased (p<0.05) for both chilled and frozen mackerel with storage time, and the rate of increase was higher in chilled than frozen mackerel. The TVBN and TMA of chilled mackerel increased significantly during storage time, but the values declined in frozen mackerel which might be due to inhibitory effects of freezing on the bacterial activities and hence avoid accumulation of TMA. Based on the chemical analyses, chilled mackerel spoiled rapidly compared to frozen mackerel. (author)

  11. Microparticles variability in fresh frozen plasma: preparation protocol and storage time effects.

    Science.gov (United States)

    Kriebardis, Anastasios G; Antonelou, Marianna H; Georgatzakou, Hara T; Tzounakas, Vassilis L; Stamoulis, Konstantinos E; Papassideri, Issidora S

    2016-05-01

    Extracellular vesicles or microparticles exhibiting procoagulant and thrombogenic activity may contribute to the haemostatic potential of fresh frozen plasma. Fresh frozen plasma was prepared from platelet-rich plasma at 20 °C (Group-1 donors) or directly from whole blood at 4 °C (Group-2 donors). Each unit was aseptically divided into three parts, stored frozen for specific periods of time, and analysed by flow cytometry for procoagulant activity immediately after thaw or following post-thaw storage for 24 h at 4 °C. Donors' haematologic, biochemical and life-style profiles as well as circulating microparticles were analysed in parallel. Circulating microparticles exhibited a considerable interdonor but not intergroup variation. Fresh frozen plasma units were enriched in microparticles compared to plasma in vivo. Duration of storage significantly affected platelet- and red cell-derived microparticles. Fresh frozen plasma prepared directly from whole blood contained more residual platelets and more platelet-derived microparticles compared to fresh frozen plasma prepared from platelet-rich plasma. Consequently, there was a statistically significant difference in total, platelet- and red cell-derived microparticles between the two preparation protocols over storage time in the freezer. Preservation of the thawed units for 24 h at 4 °C did not significantly alter microparticle accumulation. Microparticle accumulation and anti-oxidant capacity of fresh frozen plasma was positively or negatively correlated, respectively, with the level of circulating microparticles in individual donors. The preparation protocol and the duration of storage in the freezer, independently and in combination, influenced the accumulation of microparticles in fresh frozen plasma units. In contrast, storage of thawed units for 24 h at 4 °C had no significant effect on the concentration of microparticles.

  12. Accuracy of frozen section in borderline ovarian tumor

    Directory of Open Access Journals (Sweden)

    Maryam Dadzan

    2015-01-01

    Full Text Available Borderline ovarian tumor or low malignant ovarian tumor presents in 10-15% of all ovarian cancers, which usually affects younger women and have favorable prognosis even with conservative surgery, in which fertility can be preserved. Lack of reliable diagnostic tool to indicate the type of malignancy before or at the time of surgery makes the borderline ovarian tumor one of the most controversial topics in gynecology. This might lead to many overtreatment cases with radical surgery or undertreatment with conservative surgery with the higher rate of overtreatment compared to under treatment.In this review article, we extensively searched for all reported data regarding the accuracy of frozen section in borderline ovarian tumor. Reviewing the results of six studies, which specifically considered the accuracy of frozen section in borderline ovarian tumors, revealed an accuracy of 60% with an agreement between final pathology and frozen section results. Overall, 24.5% of under-diagnosed malignant cases interpreted to be benign and 4.9% overdiagnosed cases with benign tumor considered as a malignant. Frozen section is a reliable tool to exclude benign tumor from borderline and malignant but underdiagnosed percentage is higher. There are limitations in this review including the small number of enrolled cases, different time of diagnosis and different investigated countries and the discrepancies between the studied articles in this review.

  13. Crystallization of Trehalose in Frozen Solutions and its Phase Behavior during Drying

    Energy Technology Data Exchange (ETDEWEB)

    Sundaramurthi, Prakash; Patapoff, Thomas W.; Suryanarayanan, Raj (Genentech); (UMM)

    2015-02-19

    To study the crystallization of trehalose in frozen solutions and to understand the phase transitions during the entire freeze-drying cycle. Aqueous trehalose solution was cooled to -40 C in a custom-designed sample holder. The frozen solution was warmed to -18 C and annealed, and then dried in the sample chamber of the diffractometer. XRD patterns were continuously collected during cooling, annealing and drying. After cooling, hexagonal ice was the only crystalline phase observed. However, upon annealing, crystallization of trehalose dihydrate was evident. Seeding the frozen solution accelerated the solute crystallization. Thus, phase separation of the lyoprotectant was observed in frozen solutions. During drying, dehydration of trehalose dihydrate yielded a substantially amorphous anhydrous trehalose. Crystallization of trehalose, as trehalose dihydrate, was observed in frozen solutions. The dehydration of the crystalline trehalose dihydrate to substantially amorphous anhydrate occurred during drying. Therefore, analyzing the final lyophile will not reveal crystallization of the lyoprotectant during freeze-drying. The lyoprotectant crystallization can only become evident by continuous monitoring of the system during the entire freeze-drying cycle. In light of the phase separation of trehalose in frozen solutions, its ability to serve as a lyoprotectant warrants further investigation.

  14. Mapping Agricultural Frozen Soil on the Watershed Scale Using Remote Sensing Data

    International Nuclear Information System (INIS)

    Khaldoune, J; Bernier, M; Van Bochove, E; Nolin, M.C

    2011-01-01

    This paper presents an empirical model for classifying frozen/unfrozen soils in the entire Bras d Henri River watershed (167 km 2 ) near Quebec City (Quebec, Canada). It was developed to produce frozen soil maps under snow cover using RADARSAT-1 fine mode images and in situ data during three winters. Twelve RADARSAT-1 images were analyzed from fall 2003 to spring 2006 to discern the intra- and inter annual variability of frozen soil characteristics. Regression models were developed for each soil group (parent material-drainage-soil type) and land cover to establish a threshold for frozen soil from the backscattering coefficients (HH polarization). Tilled fields showed higher backscattering signal (+3 db) than the untilled fields. The overall classification accuracy was 87% for frozen soils and 94% for unfrozen soils. With respect to land use, that is, tilled versus untilled fields, an overall accuracy of 89% was obtained for the tilled fields and 92% for the untilled fields. Results show that this new mapping approach using RADARSAT-1 images can provide estimates of surface soil status (frozen/unfrozen) at the watershed scale in agricultural areas.

  15. Fresh frozen cadaver workshops for advanced vascular surgical training.

    Science.gov (United States)

    Jansen, Shirley; Cowie, Margaret; Linehan, John; Hamdorf, Jeffery M

    2014-11-01

    Reduction in working hours, streamlined training schemes and increasing use of endovascular techniques has meant a reduction in operative experience for newer vascular surgical trainees, especially those exposures which are not routinely performed such as thoracoabdominal, thoracotomy and retroperitoneal aortic, for example. This paper describes an Advanced Anatomy of Exposure course which was designed and convened at the Clinical Training & Evaluation Centre in Western Australia and uses fresh frozen cadavers. Feedback was obtained from the participants who attended over three courses by questionnaire. Feedback was strongly positive for the course meeting both its learning outcomes and personal learning objectives, and in addition, making a significant contribution to specialty skills. Most participants thought the fresh frozen cadaveric model significantly improved the learning objectives for training. The fresh frozen cadaver is an excellent teaching model highly representative of the living open surgical scenario where advanced trainees and newly qualified consultants can improve their operative confidence and consequently patient safety in vascular surgery. An efficient fresh frozen cadaver teaching programme can benefit many health professionals simultaneously maximizing the use of donated human tissue. © 2013 Royal Australasian College of Surgeons.

  16. Charge transfer rates for xenon Rydberg atoms at metal and semiconductor surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Dunning, F.B. [Department of Physics and Astronomy, Rice University, MS 61, 6100 Main Street, Houston, TX 77005-1892 (United States)]. E-mail: fbd@rice.edu; Wethekam, S. [Institut fuer Physik der Humboldt-Universitaet zu Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Dunham, H.R. [Department of Physics and Astronomy, Rice University, MS 61, 6100 Main Street, Houston, TX 77005-1892 (United States); Lancaster, J.C. [Department of Physics and Astronomy, Rice University, MS 61, 6100 Main Street, Houston, TX 77005-1892 (United States)

    2007-05-15

    Recent progress in the study of charge exchange between xenon Rydberg atoms and surfaces is reviewed. Experiments using Au(1 1 1) surfaces show that under appropriate conditions each incident atom can be detected as an ion. The ionization dynamics, however, are strongly influenced by the perturbations in the energies and structure of the atomic states that occur as the ion collection field is applied and as the atom approaches the surface. These lead to avoided crossings between different atomic levels causing the atom to successively assume the character of a number of different states and lose much of its initial identity. The effects of this mixing are discussed. Efficient surface ionization is also observed at Si(1 0 0) surfaces although the ion signal is influenced by stray fields present at the surface.

  17. Nonlinear spectroscopy of the Rydberg atoms

    International Nuclear Information System (INIS)

    Delone, N.B.; Krajnov, V.P.; Shepelyanskij, D.L.

    1984-01-01

    The results of investigation into perturbation of Rydberg states (RS) of atoms in an outer alternating field (OAF) are discussed. Both highly excited states of hydrogen atom at the energy Esub(n)=-1/2n -2 (n>>1 - basic quantum number) and excited states of compound atoms with energy Esub(nl)=-1/2(n*) -2 where n*=n-delta sub(e)-effective basic quantum number, delta sub(e)-quantum defect, are implied by RS. Perturbation of atomic state in the OAF is determined not only by field strength E, but by its frequency ω as well. During OAF inclusion the initial state Esub(lambda) transits to quasienergetic at the energy Esub(lambda)(E)+-kω, where K=0, +-1, +-2, .... Solutions of the problem of quasienergetic level population is obtained only for some simple particular cases. A simple case, when a real multilevel atom is replaced by a model system comprising one bound electron state with the basic quantum number n-model of the insulated level (MIL) is considered. Conditions of MIL applicability are discussed. Estimation of critical OAF strength at which MIL approximation becomes faulty are discussed. It is stated that any consideration of RS perturbation in OAF claiming to exceeding MIL frames should comprise consideration of ionization processes. If one keeps to the frames of OAF; the strength of which is lower than the determined critical values then MIL is true and use of this model permits to correctly describe the main features of RS perturbation in an alternating field

  18. Range of motion of diabetic frozen shoulder recovers to the contralateral level

    Science.gov (United States)

    Vastamäki, Heidi; Ristolainen, Leena

    2016-01-01

    Objective To determine whether frozen shoulder heals equally well in patients with and without diabetes and whether dependency on insulin affects the outcome. Methods We retrospectively examined 178 patients with idiopathic frozen shoulder; 27 patients had diabetes. We evaluated range of motion, pain, and functional results. The mean follow-up was 9.7 years (SD, 7.1 years). Results In the presence of frozen shoulder, range of motion did not differ between patients with and without diabetes. At follow-up, range of motion in all directions of both the affected and unaffected shoulders of patients with diabetes was inferior to that of patients without diabetes. Among patients with diabetes, range of motion of the once-frozen shoulder reached the level of the unaffected shoulder. Patients with and without diabetes experienced similar pain except during exertion. The Constant–Murley score was not significantly different between the two groups, and insulin dependency did not lead to worse outcomes. Conclusion Frozen shoulder heals well in patients with diabetes. PMID:27856934

  19. Utility of intraoperative frozen sections in surgical decision making for acute invasive fungal rhinosinusitis.

    Science.gov (United States)

    Papagiannopoulos, Peter; Lin, Diana Murro; Al-Khudari, Samer; Rajan, Kumar; Reddy, Swathi; Gattuso, Paulo; Tajudeen, Bobby; Batra, Pete S

    2017-05-01

    Acute invasive fungal rhinosinusitis (AIFRS) represents a fulminant, potentially fatal, disease process in immunocompromised patients. The diagnosis often rests on high index of clinical suspicion, with relative paucity of data on the diagnostic and therapeutic implications of intraoperative frozen sections. Retrospective review was performed for 18 cases undergoing endoscopic sinus surgery for AIFRS. Reliability of intraoperative frozen section diagnosis was evaluated for all patients using final pathology as the gold standard. A total of 66 frozen sections were performed. Diagnostic accuracy of frozen sections illustrated sensitivity of 72.7% (95% confidence interval [CI], 0.57 to 0.85), specificity of 100% (95% CI, 0.85 to 1.00), positive predictive value (PPV) of 100% (95% CI, 0.89 to 1.00), and negative predictive value (NPV) of 64.7% (95% CI, 0.46 to 0.80). There was no statistically significant difference in sensitivity of frozen sections in cases of Mucor and Aspergillus at 68.8%% and 76.2%, respectively (p = 0.61). This study represents the largest series assessing the diagnostic accuracy of frozen section analysis in AIFRS. Frozen section analysis is an effective tool for guiding intraoperative decision making in patients with AIFRS with a high PPV. A Low NPV underscores the importance of clinical suspicion and intraoperative decision making based on endoscopic findings when negative frozen section results are encountered. Further, frozen section analysis appears to be equally effective in detecting either Mucor or Aspergillus. © 2017 ARS-AAOA, LLC.

  20. Combined theoretical and experimental study of the valence, Rydberg, and ionic states of chlorobenzene

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, Michael H., E-mail: m.h.palmer@ed.ac.uk; Ridley, Trevor, E-mail: tr01@staffmail.ed.ac.uk, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: malgorzata.biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, Scotland (United Kingdom); Vrønning Hoffmann, Søren, E-mail: tr01@staffmail.ed.ac.uk, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: malgorzata.biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu; Jones, Nykola C., E-mail: tr01@staffmail.ed.ac.uk, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: malgorzata.biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Coreno, Marcello, E-mail: tr01@staffmail.ed.ac.uk, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: malgorzata.biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [CNR-ISM, Basovizza Area Science Park, 1-34149 Trieste (Italy); De Simone, Monica, E-mail: tr01@staffmail.ed.ac.uk, E-mail: vronning@phys.au.dk, E-mail: nykj@phys.au.dk, E-mail: marcello.coreno@elettra.eu, E-mail: desimone@iom.cnr.it, E-mail: malgorzata.biczysko@shu.edu.cn, E-mail: alberto.baiardi@sns.it, E-mail: kipeters@wsu.edu [CNR-IOM Laboratorio TASC, Trieste (Italy); Grazioli, Cesare [CNR-IOM Laboratorio TASC, Trieste (Italy); Department of Chemical and Pharmaceutical Sciences, University of Trieste, Trieste (Italy); Zhang, Teng [Department of Physics and Astronomy, University of Uppsala, Uppsala (Sweden); and others

    2016-03-28

    New photoelectron (PE) and ultra violet (UV) and vacuum UV (VUV) spectra have been obtained for chlorobenzene by synchrotron study with higher sensitivity and resolution than previous work and are subjected to detailed analysis. In addition, we report on the mass-resolved (2 + 1) resonance enhanced multiphoton ionization (REMPI) spectra of a jet-cooled sample. Both the VUV and REMPI spectra have enabled identification of a considerable number of Rydberg states for the first time. The use of ab initio calculations, which include both multi-reference multi-root doubles and singles configuration interaction (MRD-CI) and time dependent density functional theoretical (TDDFT) methods, has led to major advances in interpretation of the vibrational structure of the ionic and electronically excited states. Franck-Condon (FC) analyses of the PE spectra, including both hot and cold bands, indicate much more complex envelopes than previously thought. The sequence of ionic states can be best interpreted by our multi-configuration self-consistent field computations and also by comparison of the calculated vibrational structure of the B and C ionic states with experiment; these conclusions suggest that the leading sequence is the same as that of iodobenzene and bromobenzene, namely: X{sup 2}B{sub 1}(3b{sub 1}{sup −1}) < A{sup 2}A{sub 2}(1a{sub 2}{sup −1}) < B{sup 2}B{sub 2}(6b{sub 2}{sup −1}) < C{sup 2}B{sub 1}(2b{sub 1}{sup −1}). The absorption onset near 4.6 eV has been investigated using MRD-CI and TDDFT calculations; the principal component of this band is {sup 1}B{sub 2} and an interpretation based on the superposition of FC and Herzberg-Teller contributions has been performed. The other low-lying absorption band near 5.8 eV is dominated by a {sup 1}A{sub 1} state, but an underlying weak {sup 1}B{sub 1} state (πσ{sup ∗}) is also found. The strongest band in the VUV spectrum near 6.7 eV is poorly resolved and is analyzed in terms of two ππ{sup ∗} states of

  1. Van-der-Waals interaction of atoms in dipolar Rydberg states

    Science.gov (United States)

    Kamenski, Aleksandr A.; Mokhnenko, Sergey N.; Ovsiannikov, Vitaly D.

    2018-02-01

    An asymptotic expression for the van-der-Waals constant C 6( n) ≈ -0.03 n 12 K p ( x) is derived for the long-range interaction between two highly excited hydrogen atoms A and B in their extreme Stark states of equal principal quantum numbers n A = n B = n ≫ 1 and parabolic quantum numbers n 1(2) = n - 1, n 2(1) = m = 0 in the case of collinear orientation of the Stark-state dipolar electric moments and the interatomic axis. The cubic polynomial K 3( x) in powers of reciprocal values of the principal quantum number x = 1/ n and quadratic polynomial K 2( y) in powers of reciprocal values of the principal quantum number squared y = 1/ n 2 were determined on the basis of the standard curve fitting polynomial procedure from the calculated data for C 6( n). The transformation of attractive van-der-Waals force ( C 6 > 0) for low-energy states n < 23 into repulsive force ( C 6 < 0) for all higher-energy states of n ≥ 23, is observed from the results of numerical calculations based on the second-order perturbation theory for the operator of the long-range interaction between neutral atoms. This transformation is taken into account in the asymptotic formulas (in both cases of p = 2, 3) by polynomials K p tending to unity at n → ∞ ( K p (0) = 1). The transformation from low- n attractive van-der-Waals force into high- n repulsive force demonstrates the gradual increase of the negative contribution to C 6( n) from the lower-energy two-atomic states, of the A(B)-atom principal quantum numbers n'A(B) = n-Δ n (where Δ n = 1, 2, … is significantly smaller than n for the terms providing major contribution to the second-order series), which together with the states of n″B(A) = n+Δ n make the joint contribution proportional to n 12. So, the hydrogen-like manifold structure of the energy spectrum is responsible for the transformation of the power-11 asymptotic dependence C 6( n) ∝ n 11of the low-angular-momenta Rydberg states in many-electron atoms into the power

  2. Historical and future changes of frozen ground in the upper Yellow River Basin

    Science.gov (United States)

    Wang, Taihua; Yang, Dawen; Qin, Yue; Wang, Yuhan; Chen, Yun; Gao, Bing; Yang, Hanbo

    2018-03-01

    Frozen ground degradation resulting from climate warming on the Tibetan Plateau has aroused wide concern in recent years. In this study, the maximum thickness of seasonally frozen ground (MTSFG) is estimated by the Stefan equation, which is validated using long-term frozen depth observations. The permafrost distribution is estimated by the temperature at the top of permafrost (TTOP) model, which is validated using borehole observations. The two models are applied to the upper Yellow River Basin (UYRB) for analyzing the spatio-temporal changes in frozen ground. The simulated results show that the areal mean MTSFG in the UYRB decreased by 3.47 cm/10 a during 1965-2014, and that approximately 23% of the permafrost in the UYRB degraded to seasonally frozen ground during the past 50 years. Using the climate data simulated by 5 General Circulation Models (GCMs) under the Representative Concentration Pathway (RCP) 4.5, the areal mean MTSFG is projected to decrease by 1.69 to 3.07 cm/10 a during 2015-2050, and approximately 40% of the permafrost in 1991-2010 is projected to degrade into seasonally frozen ground in 2031-2050. This study provides a framework to estimate the long-term changes in frozen ground based on a combination of multi-source observations at the basin scale, and this framework can be applied to other areas of the Tibetan Plateau. The estimates of frozen ground changes could provide a scientific basis for water resource management and ecological protection under the projected future climate changes in headwater regions on the Tibetan Plateau.

  3. Determination of several common disinfection by-products in frozen foods.

    Science.gov (United States)

    Cardador, Maria Jose; Gallego, Mercedes

    2018-01-01

    Disinfected water and/or disinfectants are commonly used by the freezing industry in such processes as sanitising, washing, blanching, cooling and transporting the final product. For this reason, disinfection by-products (DBPs) can be expected in frozen foods. This study focused on the presence of DBPs in a wide variety of frozen vegetables, meats and fish. For this purpose, the 14 halogenated DBPs more prevalent in disinfected water were selected (four trihalomethanes, seven haloacetic acids, two haloacetonitriles and trichloronitromethane). Up to seven DBPs were found in vegetables, whereas only four DBPs were present in meats and fish, and at lower concentrations, since their contact with disinfected water is lower than in frozen vegetables. It is important to emphasise that trichloronitromethane (the most abundant nitrogenous DBP in disinfected water) was found for the first time in foods. Finally, it was concluded that the freezing process can keep the compounds stable longer than other preservation processes (viz. sanitising, canning) and, therefore, frozen foods present higher DBP concentrations than other food categories (minimally processed vegetables, or canned vegetables and meats).

  4. Production of Molecular Iodine and Tri-iodide in the Frozen Solution of Iodide: Implication for Polar Atmosphere.

    Science.gov (United States)

    Kim, Kitae; Yabushita, Akihiro; Okumura, Masanori; Saiz-Lopez, Alfonso; Cuevas, Carlos A; Blaszczak-Boxe, Christopher S; Min, Dae Wi; Yoon, Ho-Il; Choi, Wonyong

    2016-02-02

    The chemistry of reactive halogens in the polar atmosphere plays important roles in ozone and mercury depletion events, oxidizing capacity, and dimethylsulfide oxidation to form cloud-condensation nuclei. Among halogen species, the sources and emission mechanisms of inorganic iodine compounds in the polar boundary layer remain unknown. Here, we demonstrate that the production of tri-iodide (I3(-)) via iodide oxidation, which is negligible in aqueous solution, is significantly accelerated in frozen solution, both in the presence and the absence of solar irradiation. Field experiments carried out in the Antarctic region (King George Island, 62°13'S, 58°47'W) also showed that the generation of tri-iodide via solar photo-oxidation was enhanced when iodide was added to various ice media. The emission of gaseous I2 from the irradiated frozen solution of iodide to the gas phase was detected by using cavity ring-down spectroscopy, which was observed both in the frozen state at 253 K and after thawing the ice at 298 K. The accelerated (photo-)oxidation of iodide and the subsequent formation of tri-iodide and I2 in ice appear to be related with the freeze concentration of iodide and dissolved O2 trapped in the ice crystal grain boundaries. We propose that an accelerated abiotic transformation of iodide to gaseous I2 in ice media provides a previously unrecognized formation pathway of active iodine species in the polar atmosphere.

  5. Sensory Properties of Frozen Herring (Clupea harengus) from Different Catch Seasons and Locations

    DEFF Research Database (Denmark)

    Hyldig, Grethe; Jørgensen, Bo Munk; Undeland, Ingrid

    2012-01-01

    Freezing of herring (Clupea harengus) for human consumption is increasing in the Nordic herring industry, either onboard the fishing vessels or right after landing. The quality of frozen herring as a raw material does not only depend on the frozen storage conditions applied, but also...... on compositional features, something which in turn can vary with season and catching ground. To unravel the link between biological variations, basic muscle composition, and sensory properties of frozen herring, a unique herring raw material was caught by commercial fishing vessels at three locations: around...... the utilization of herring for frozen storage for human consumption....

  6. Properties of concrete mixed with sand frozen by liquid nitrogen

    International Nuclear Information System (INIS)

    Negami, Yoshiaki; Kurita, Morio; Kuwahara, Takashi; Goto, Sadao.

    1990-01-01

    This paper presents a new precooling method which reduces the temperature of mixed concrete by mixing it with sand frozen by liquid nitrogen. The authors tried to clarify the properties of both the frozen sand and the concrete mixed with the frozen sand. The results of a series of experimental studies indicate that the temperature of mixed concrete can be reduced about 25degC, which is a larger reduction quantity than that achieved by conventional precooling methods; and that this method contributes to improvement of the consistency and the compressive strength of the concrete. Furthermore, the advantageous effect of this precooling method is confirmed from the results of laboratory tests using massive concrete members. (author)

  7. Construction and test of the Bonn frozen spin target

    International Nuclear Information System (INIS)

    Dutz, H.

    1989-04-01

    For γN→ΠN and γd→pn scattering experiments at the PHOENICS detector, a new 'bonn frozen spin target' (BOFROST) is developed. The target with a maximum volume of 30 cm 3 is cooled in a vertical 3 He- 4 He dilution kryostat. The lowest temperature of the dilution kryostat in the frozen spin mode should be 50 mk. In a first stage, the magnet system consist of two superconducting solenoids: A polarisation magnet with a maximum field of 7 T with a homogenity of 10 -5 over the target area and a 'vertical holding' magnet with a maximum field in the target area of 0.57 T. This work describes the construction and the set-up of the 'frozen spin target' in the laboratory and the first tests of the dilution kryostat and the superconducting magnet system. (orig.) [de

  8. Treatment for Frozen Shoulder Combined with Calcific Tendinitis of the Supraspinatus

    Directory of Open Access Journals (Sweden)

    Shen-Kai Chen

    2008-02-01

    Full Text Available Calcific tendinitis of the shoulder is a process that involves calcium deposition in the rotator cuff tendons. It is usually a self-limiting process and is often chronic in nature. However, it can lead to acute pain resulting in frozen shoulder syndrome. We report 32 cases in which frozen shoulder was associated with calcific tendinitis of the supraspinatus. The aim of this study was to use arthroscopic brisement of the glenohumeral joint and make multiple punctures in the calcific spot to treat the frozen shoulder associated with calcific tendinitis of the supraspinatus. In our study, 30 patients had satisfactory results after a 2-year follow-up. Five patients experienced some postoperative calcium shadows, but there was also greater improvement in the range of motion and pain relief in this study compared with other reports in the literature of frozen shoulder cases.

  9. Detection method of prawn irradiated in frozen state using tyrosine isomers as a marker

    International Nuclear Information System (INIS)

    Oikawa, H.; Satomi, M.; Omura, Y.; Yano, Y.

    2001-01-01

    Internationally the use of food irradiation has been expanding. And therefore a method is needed to detect whether food has been irradiated or not. We examined the content of the tyrosine isomers, m-tyrosine and omicron-tyrosine, of prawns irradiated in the frozen state (< -30 deg C) as a marker of the detection method. The tyrosine isomer content linearly increased with increasing dose, and the level of tyrosine isomers in the frozen-irradiated prawn was 50 - 60 % of the un frozen ones. But the difference in the content of tyrosine isomers between non-irradiated and irradiated at 5.0 kGy, that is the approved dose for frozen shellfish in countries where this technique is approved, is enough for discrimination. In addition, the content of tyrosine isomers showed little change during the frozen storage for 120 days. So we think the method using tyrosine isomers is suitable for practical use in Japan for imports of many kinds of frozen shellfish

  10. Incidence and prognostic factors for postoperative frozen shoulder after shoulder surgery: a prospective cohort study.

    Science.gov (United States)

    Koorevaar, Rinco C T; Van't Riet, Esther; Ipskamp, Marcel; Bulstra, Sjoerd K

    2017-03-01

    Frozen shoulder is a potential complication after shoulder surgery. It is a clinical condition that is often associated with marked disability and can have a profound effect on the patient's quality of life. The incidence, etiology, pathology and prognostic factors of postoperative frozen shoulder after shoulder surgery are not known. The purpose of this explorative study was to determine the incidence of postoperative frozen shoulder after various operative shoulder procedures. A second aim was to identify prognostic factors for postoperative frozen shoulder after shoulder surgery. 505 consecutive patients undergoing elective shoulder surgery were included in this prospective cohort study. Follow-up was 6 months after surgery. A prediction model was developed to identify prognostic factors for postoperative frozen shoulder after shoulder surgery using the TRIPOD guidelines. We nominated five potential predictors: gender, diabetes mellitus, type of physiotherapy, arthroscopic surgery and DASH score. Frozen shoulder was identified in 11% of the patients after shoulder surgery and was more common in females (15%) than in males (8%). Frozen shoulder was encountered after all types of operative procedures. A prediction model based on four variables (diabetes mellitus, specialized shoulder physiotherapy, arthroscopic surgery and DASH score) discriminated reasonably well with an AUC of 0.712. Postoperative frozen shoulder is a serious complication after shoulder surgery, with an incidence of 11%. Four prognostic factors were identified for postoperative frozen shoulder: diabetes mellitus, arthroscopic surgery, specialized shoulder physiotherapy and DASH score. The combination of these four variables provided a prediction rule for postoperative frozen shoulder with reasonable fit. Level II, prospective cohort study.

  11. Frozen reaction fronts in steady flows: A burning-invariant-manifold perspective

    Science.gov (United States)

    Mahoney, John R.; Li, John; Boyer, Carleen; Solomon, Tom; Mitchell, Kevin A.

    2015-12-01

    The dynamics of fronts, such as chemical reaction fronts, propagating in two-dimensional fluid flows can be remarkably rich and varied. For time-invariant flows, the front dynamics may simplify, settling in to a steady state in which the reacted domain is static, and the front appears "frozen." Our central result is that these frozen fronts in the two-dimensional fluid are composed of segments of burning invariant manifolds, invariant manifolds of front-element dynamics in x y θ space, where θ is the front orientation. Burning invariant manifolds (BIMs) have been identified previously as important local barriers to front propagation in fluid flows. The relevance of BIMs for frozen fronts rests in their ability, under appropriate conditions, to form global barriers, separating reacted domains from nonreacted domains for all time. The second main result of this paper is an understanding of bifurcations that lead from a nonfrozen state to a frozen state, as well as bifurcations that change the topological structure of the frozen front. Although the primary results of this study apply to general fluid flows, our analysis focuses on a chain of vortices in a channel flow with an imposed wind. For this system, we present both experimental and numerical studies that support the theoretical analysis developed here.

  12. Frozen fruit skin prick test for the diagnosis of fruit allergy.

    Science.gov (United States)

    Garriga, Teresa; Guilarte, Mar; Luengo, Olga; Guillén, Mercé; Labrador-Horrillo, Moisés; Fadeeva, Tatiana; Sala, Anna; Cardona, Victória

    2010-12-01

    Diagnosis of fruit sensitisation by skin prick test (SPT) is fast and easy to perform. Nevertheless, some fruit is not available throughout the year. Freezing aliquots of these fresh fruits to be defrosted would be a good solution to perform SPT at any time. To compare the reproducibility of SPT with Rosaceae and Cucurbitaceae frozen fruit with fresh and commercial fruit extracts. SPT with the following fruit were performed: apricot, cherry, strawberry, nectarine, Japanese medlar, peach, (peel and pulp), yellow and red plum, melon and watermelon. We compared fresh fruit, commercial extract and fruit which had been frozen at -18 degrees C. Results were read by planimetry (Inmunotek prick-film) after 15 minutes. The study group comprised 48 patients (9 males, 39 females) with a mean age of 31, 6 +/- 2.0 years. Concordance of positive and negative results was extremely high and significant in all cases. Correlation between frozen fruit and commercial extract, frozen fruit and fresh and commercial extract and fresh fruit was statistically significant in all cases except for strawberry. The use of frozen fruit is a valid method, as the performance of the SPT is similar to that of fresh fruit. This enables diagnostic procedures with seasonal fruit at any time of the year.

  13. Gas-assisted injection moulding: adding two components and moveable inserts

    NARCIS (Netherlands)

    Neerincx, P.E.; Meijer, H.E.H.

    2009-01-01

    Gas assisted injection moulding (GAIM) is a technique that is successfully used for compensating shrinkage during injection moulding of thick walled but still accurate products with low levels of internal stresses and frozen-in orientation. In this study the authors apply GAIM in moulding 28 mm

  14. The Jefferson Lab Frozen Spin Target

    Energy Technology Data Exchange (ETDEWEB)

    Christopher Keith, James Brock, Christopher Carlin, Sara Comer, David Kashy, Josephine McAndrew, David Meekins, Eugene Pasyuk, Joshua Pierce, Mikell Seely

    2012-08-01

    A frozen spin polarized target, constructed at Jefferson Lab for use inside a large acceptance spectrometer, is described. The target has been utilized for photoproduction measurements with polarized tagged photons of both longitudinal and circular polarization. Protons in TEMPO-doped butanol were dynamically polarized to approximately 90% outside the spectrometer at 5 T and 200-300 mK. Photoproduction data were acquired with the target inside the spectrometer at a frozen-spin temperature of approximately 30 mK with the polarization maintained by a thin, superconducting coil installed inside the target cryostat. A 0.56 T solenoid was used for longitudinal target polarization and a 0.50 T dipole for transverse polarization. Spin relaxation times as high as 4000 hours were observed. We also report polarization results for deuterated propanediol doped with the trityl radical OX063.

  15. Analytical procedures for bulk frozen-hydrated biological tissues

    International Nuclear Information System (INIS)

    Echlin, P.; Hayes, T.L.; McKoon, M.

    1983-01-01

    The main advantage of using solid frozen samples for elemental x-ray microanalysis is the ease with which they may be prepared and maintained in the frozen-hydrated state. Within the limits imposed by the reduced spatial resolution of the method, the morphological identification of the tissue components is comparatively easy. Bearing in mind these limitations, the authors have carried out an analysis for several elements in the developing root tips of Lemna minor L (Duckweed). Fresh root tips of Lemna minor L, briefly encapsulated in a polymeric cryoprotectant, are quench frozen in melting nitrogen at ca. 70 0 K and transferred to the pre-cooled cold stage of an AMray Biochamber. The analysis was carried out by means of a Kevex energy-dispersive detector by use of the peak-to-background ratio method. These procedures allow the authors to obtain flat fracture faces in which they have been able to measure the relative concentrations of various elements at the various stages of differentiation in the root tissue

  16. Exponential and nonexponential localization of the one-dimensional periodically kicked Rydberg atom

    International Nuclear Information System (INIS)

    Yoshida, S.; Reinhold, C. O.; Kristoefel, P.; Burgdoerfer, J.

    2000-01-01

    We investigate the quantum localization of the one-dimensional Rydberg atom subject to a unidirectional periodic train of impulses. For high frequencies of the train the classical system becomes chaotic and leads to fast ionization. By contrast, the quantum system is found to be remarkably stable. We identify for this system the coexistence of different localization mechanisms associated with resonant and nonresonant diffusion. We find for the suppression of nonresonant diffusion an exponential localization whose localization length can be related to the classical dynamics in terms of the ''scars'' of the unstable periodic orbits. We show that the localization length is determined by the energy excursion along the periodic orbits. The suppression of resonant diffusion along the sequence of photonic peaks is found to be nonexponential due to the presence of high harmonics in the driving force. (c) 2000 The American Physical Society

  17. Multiphoton microscopy based cryo-imaging of inflated frozen human lung sections at -60°C in healthy and COPD lungs

    Science.gov (United States)

    Abraham, Thomas; Kayra, Damian; Zhang, Angela; Suzuki, Masaru; McDonough, John; Elliott, W. M.; Cooper, Joel D.; Hogg, James C.

    2013-02-01

    Lung is a complex gas exchanger with interfacial area (where the gas exchange takes place) is about the size of a tennis court. Respiratory function is linked to the biomechanical stability of the gas exchange or alveolar regions which directly depends on the spatial distributions of the extracellular matrix fibers such fibrillar collagens and elastin fibers. It is very important to visualize and quantify these fibers at their native and inflated conditions to have correct morphometric information on differences between control and diseased states. This can be only achieved in the ex vivo states by imaging directly frozen lung specimens inflated to total lung capacity. Multiphoton microscopy, which uses ultra-short infrared laser pulses as the excitation source, produces multiphoton excitation fluorescence (MPEF) signals from endogenously fluorescent proteins (e.g. elastin) and induces specific second harmonic generation (SHG) signals from non-centrosymmetric proteins such as fibrillar collagens in fresh human lung tissues [J. Struct. Biol. (2010)171,189-196]. Here we report for the first time 3D image data obtained directly from thick frozen inflated lung specimens (~0.7- 1.0 millimeter thick) visualized at -60°C without prior fixation or staining in healthy and diseased states. Lung specimens donated for transplantation and released for research when no appropriate recipient was identified served as controls, and diseased lung specimens donated for research by patients receiving lung transplantation for very severe COPD (n=4) were prepared as previously described [N. Engl. J. Med. (2011) 201, 1567]. Lung slices evenly spaced between apex and base were examined using multiphoton microscopy while maintained at -60°C using a temperature controlled cold stage with a temperature resolution of 0.1°C. Infrared femto-second laser pulses tuned to 880nm, dry microscopic objectives, and non-de-scanned detectors/spectrophotometer located in the reflection geometry were

  18. Fine needle aspiration cytology versus frozen section in branchial cleft cysts.

    Science.gov (United States)

    Begbie, F; Visvanathan, V; Clark, L J

    2015-02-01

    Branchial cleft cysts occur because of a failure of involution of the second branchial cleft. However, as well-differentiated squamous cell carcinoma can mimic branchial cleft cysts, there is a lack of consensus on the appropriate management of cystic neck lumps. To report our experience of fine needle aspiration cytology and frozen section examination in the management of cystic neck lumps. Retrospective case note review of patients managed in the Southern General Hospital, Scotland, UK. The sensitivity of fine needle aspiration cytology and frozen section for detecting branchial cleft cysts was 75 per cent and 100 per cent respectively. Two patients who did not undergo intra-operative frozen section examination were either over- or under-treated, which is discussed. Adult patients subjected to surgical excision of a suspected branchial cyst should undergo intra-operative frozen section analysis regardless of clinical suspicion for malignancy. This part of management is critical to ensure patients are offered appropriate treatment.

  19. Recoil halogen reactions in liquid and frozen aqueous solutions of biomolecules

    International Nuclear Information System (INIS)

    Arsenault, L.J.; Blotcky, A.J.; Firouzbakht, M.L.; Rack, E.P.; Nebraska Univ., Omaha

    1982-01-01

    Reactions of recoil 38 Cl, 80 Br and 128 I have been studied in crystalline systems of 5-halouracil, 5-halo-2'-deoxyuridine and 5-halouridine as well as liquid and frozen aqueous solutions of these halogenated biomolecules. In all systems expect crystalline 5-iuodouracil the major product was the radio-labelled halide ion. There was no evidence for other halogen inorganic species. The major labelled organic product was the parent molecule. A recoil atom tracer technique was developed to acquire site information of the biomolecule solutes in the liquid and frozen aqueous systems. For all liquid and frozen aqueous systems, the halogenated biomolecules tended to aggregate. For liquid systems, the tendency for aggregation diminished as the solute concentration approached zero, where the probable state of the solute approached a monomolecular dispersion. Unlike the liquid state, the frozen ice lattice demonstated a ''caging effect'' for the solute aggregates which resulted in constant product yields over the whole concentration range. (orig.)

  20. Analytical Method for Differentiation of Chilled and Frozen-Thawed Chicken Meat

    Directory of Open Access Journals (Sweden)

    Ivanova Ivelina

    2014-12-01

    Full Text Available : Chilled and frozen chicken breast and thigh meat were stored at +4±1 oC and - 20±1 oC, respectively. Maillard reaction between ribose and meat proteins of the chicken samples was initiated. The changes in the ribose-induced Maillard reaction rate during chilled and frozen storage of chicken meat were evaluated on the bases of corrected absorbance values (A420* and bovine melanoidin equivalent values (mg BME/g. Application of BME as a measure of ribose-induced Maillard reaction rate enables comparability of the data obtained by different spectrophotometers. It was found that the BME values of chicken meat frozen stored for more than 15 days were significantly (P<0.05 lower than BME values of chilled-stored samples. According to the suggested threshold limit values the chicken thigh and breast meat with BME values lower than 30 mg BME/g and 51 mg BME/g, respectively could be classified as frozen-thawed.

  1. Effects of finite temperature on two-photon transitions in a Rydberg atom in a high-Q cavity

    International Nuclear Information System (INIS)

    Puri, R.R.; Joshi, A.

    1989-01-01

    The effects of cavity temperature on an effective two-level atom undergoing two-photon transitions in a high-Q cavity are investigated. The quantum statistical properties of the field and the dynamical properties of the atom in this case are studied and compared with those for an atom making one-photon transitions between the two levels. The analysis is based on the solution of the equation for the density matrix in the secular approximation which is known to be a valid approximation in the case of a Rydberg atom in a high-Q cavity. (orig.)

  2. Diagnostic power and pitfalls of intraoperative consultation (frozen section) in rhabdomyosarcoma.

    Science.gov (United States)

    Kurtulan, Olcay; Kösemehmetoğlu, Kemal

    2015-01-01

    Intraoperative consultation plays an important role in the management of soft tissue sarcomas, such as rhabdomyosarcoma. In this study, we aimed to draw attention to the important points during frozen section interpretation, and analyse the accuracy of frozen diagnosis in rhabdomyosarcoma patients. The cases, both diagnosed as rhabdomyosarcoma or followed with a history of rhabdomyosarcoma, and interpreted with intraoperative consultation (frozen section) between 2000 and 2013 were culled from pathology archives. The diagnoses were confirmed by desmin and myogenin, immunohistochemically. The frozen and final diagnoses were noted of 21 biopsy specimens of 19 patients. Sensitivity and specificity of intraoperative consultation were calculated regarding to the major diagnostic discrepancies leading to a change in surgical management of the patient, after exclusion of the cases deferred to paraffin section. Of the evaluated 21 biopsy material, 3 (14%) were misdiagnosed: Of the 2 false negative embryonal rhabdomyosarcoma cases, sample was not representative of the tumor, and there was chemo/radiotherapy induced changes in the other case. In the only false positively diagnosed case with a known history of rhabdomyosarcoma, inflammatory cells were misinterpreted as small round cell neoplasm. In 5 (29%) of 21 biopsies, a frozen diagnosis could not be given, and the diagnosis was deferred. Six cases (29%) were evaluated with cytological squash or imprint preparation; none of the misdiagnosed cases was evaluated with adjunct cytological preparation. Six of 8 misdiagnosed or deferred biopsies showed morphological changes secondary to radiotherapy and/or chemotherapy. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated as 85%, 67%, 92% and 50%, respectively. Intraoperative consultation for rhabdomyosarcoma is a reliable tool with high sensitivity and fair specificity. Cases with treatment effect may lead to diagnostic difficulties

  3. Frozen in time: permafrost and engineering problems

    National Research Council Canada - National Science Library

    Muller, Siemon W; French, Hugh M; Nelson, Frederick E

    2008-01-01

    ...), author of the first English-language book about perennially frozen ground.". "This book reads like a "how-to" manual for engineering personnel working in pioneering or primitive circumstances...

  4. Generation of tunable coherent far-infrared radiation using atomic Rydberg states

    International Nuclear Information System (INIS)

    Bookless, W.

    1980-12-01

    A source of tunable far-infrared radiation has been constructed. The system has been operated at 91.6 cm -1 with a demonstrated tunability of .63 cm -1 . The system is based on a Rydberg state transition in optically pumped potassium vapor. The transition energy is tuned by the application of an electric field to the excited vapor. The transition wavelength and the shifted wavelength were detected and measured by the use of a Michelson interferometer and a liquid helium cooled Ga:Ge bolometer and the data was reduced using Fast Fourier transform techniques. Extensive spectroscopy was done on the potassium vapor to elucidate the depopulation paths and rates of the excited levels. Both theoretical and experimental results are presented to support the conclusions of the research effort. Additionally, possible alternative approaches to the population of the excited state are explored and recommendations are made for the future development of this source as well as the potential uses of it in molecular spectroscopy

  5. Exciton Rydberg series in mono- and few-layer WS2

    Science.gov (United States)

    Chernikov, Alexey; Berkelbach, Timothy C.; Hill, Heather M.; Rigosi, Albert; Li, Yilei; Aslan, Özgur B.; Hybertsen, Mark S.; Reichman, David R.; Heinz, Tony F.

    2014-03-01

    Considered a long-awaited semiconducting analogue to graphene, the family of atomically thin transition metal dichalcogenides (TMDs) attracted intense interest in the scientific community due to their remarkable physical properties resulting from the reduced dimensionality. A fundamental manifestation of the two-dimensional nature is a strong increase in the Coulomb interaction. The resulting formation of tightly bound excitons plays a crucial role for a majority of optical and transport phenomena. In our work, we investigate the excitons in atomically thin TMDs by optical micro-spectroscopy and apply a microscopic, ab-initio theoretical approach. We observe a full sequence of excited exciton states, i.e., the Rydberg series, in the monolayer WS2, identifying tightly bound excitons with energies exceeding 0.3 eV - almost an order of magnitude higher than in the corresponding, three-dimensional crystal. We also find significant deviations of the excitonic properties from the conventional hydrogenic physics - a direct evidence of a non-uniform dielectric environment. Finally, an excellent quantitative agreement is obtained between the experimental findings and the developed theoretical approach.

  6. Cryoprotectant redistribution along the frozen straw probed by Raman spectroscopy.

    Science.gov (United States)

    Karpegina, Yu A; Okotrub, K A; Brusentsev, E Yu; Amstislavsky, S Ya; Surovtsev, N V

    2016-04-01

    The distribution of cryoprotectant (10% glycerol) and ice along the frozen plastic straw (the most useful container for freezing mammalian semen, oocytes and embryos) was studied by Raman scattering technique. Raman spectroscopy being a contactless, non-invasive tool was applied for the straws filled with the cryoprotectant solution and frozen by controlled rate programs commonly used for mammalian embryos freezing. Analysis of Raman spectra measured at different points along the straw reveals a non-uniform distribution of the cryoprotectant. The ratio between non-crystalline solution and ice was found to be increased by several times at the bottom side of the solution column frozen by the standard freezing program. The increase of the cryoprotectant fraction occurs in the area where embryos or oocytes are normally placed during their freezing. Possible effects of the cooling rate and the ice nucleation temperature on the cryoprotectant fraction at the bottom side of the solution column were considered. Our findings highlight that the ice fraction around cryopreserved embryos or oocytes can differ significantly from the averaged one in the frozen plastic straws. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. The effects of commercial fibres on frozen bread dough

    Directory of Open Access Journals (Sweden)

    JELENA FILIPOVIĆ

    2010-02-01

    Full Text Available The daily intake of dietary fibres in highly industrialized countries is at a low level and, therefore, adversely affecting human health. The objective of this research was to analyze the influence of different commercial fibres (originating from sugar beet pulp fibrex, and Jerusalem artichoke inulin HPX and GR in yeast dough at a level of 5 %, on the rheological properties of dough and the quality of bread during frozen storage. Frozen dough characteristics were determined using a Brabender maturograph and test baking was followed according the AACC procedure. The dough was frozen at –18 °C and stored over a period of 60 days. The results concerning the dough (proving time and stability and bread quality (volume and crumb quality were statistically analyzed by multivariance Manova and discriminative analysis, which indicated that there was a significant difference between dough without fibres and dough with different fibres (fibrex, inulin HPX and GR. The discrimination coefficient points that the greatest influence of fibres on the final proof and proving stability is after 30 days (6.250 and after 0 days (6.158, respectively, but the greatest influence of fibres on bread volume and bread crumb quality (15.488 and 3.638, respectively can be expected on non frozen dough, due to above mention their adverse the effect on gluten network.

  8. Improving survival of culture bacteria in frozen desserts by microentrapment.

    Science.gov (United States)

    Sheu, T Y; Marshall, R T; Heymann, H

    1993-07-01

    Lactobacillus bulgaricus cells were entrapped in beads of calcium alginate and evaluated for their ability to survive freezing processes. Cells survived freezing (without agitation) in ice milk mix much better than in distilled water, and more entrapped cells survived than did cells that were not entrapped. Glycerol and mannitol were cryoprotective, but glucose was not, when each was added (6%) separately to the beads. Entrapment protected the lactobacilli in batch frozen and continuously frozen ice milk mixes. The percentage of survival for entrapped and unentrapped cells in continuously frozen ice milk approximated 90 and 40%, respectively. Lactobacilli survived better in beads with mean diameters > 30 microns than in those averaging 15 microns. Addition of entrapped lactobacilli had no measurable effect on the sensory characteristics of the ice milk.

  9. Microbial quality of equine frozen semen.

    Science.gov (United States)

    Corona, A; Cherchi, R

    2009-10-01

    Bacteriological surveillance is little applied in management of equine frozen semen but it is quite important to verify the microbial contamination in order to find out the chance of transmission of pathology to the mare in AI. Authors describe a qualitative and quantitative analysis for bacterial contamination on long time (3-17 years) equine frozen semen stored in liquid nitrogen. The semen checked, produced in Italy and in another Europe country, was cryopreserved in liquid nitrogen inside sealed plastic straws. One hundred and ten straws were checked out for pathogenic and no pathogenic bacteria, aerobes and anaerobes and fungi (moulds and yeasts). The Total Microbial Charge was quite variable with an average of about 1.4 x 10(5)CFU/ml. Mostly the microbial agents identified were fungi (17.5%), Enterobacter-coccus spp. (15%), Pseudomonas spp. (6.25%), Stenothophomonas maltophila (6.25%) and anaerobic bacteria like Propionibacterium granulosum (7.5%) and Clostridium spp. (3.75%). 3.75% were unidentified Gram-negative rod and cocci. Streptococcus spp., Staph. aureus, E. coli, Th. equigenitalis and Mycoplasma spp. were not detected. The most represented species were Enterobacter-coccus spp. (1.1 x 10(5)CFU/ml), St. maltophila (8 x 10(4)CFU/ml) and Pr. granulosum (7 x 10(4)CFU/ml) while yeast and even more moulds were little abundant (4.7 x 10(4) and 3.4 x 10(4)CFU/ml respectively). The knowledge of equine frozen semen microbial quality is essential to check out transmission of venereal disease and improve the quality of cryopreserved germplasm.

  10. Effect of gamma irradiation on the sensitivities of escherichia coli at deep frozen conditions

    International Nuclear Information System (INIS)

    Takigami, Machiko; Ito, Hitoshi

    1996-01-01

    Phosphate buffer suspensions of three strains of Escherichia coli were irradiated with gamma-rays at room temperature and deep frozen conditions. They were inoculated on MacConkey agar plates to see the comparative sensitivities to the irradiation. Compared to the irradiation at room temperature, the sensitivities of the strains decreased by irradiation at deep frozen conditions. Addition of glycerol to the E. coli suspensions decreased the sensitivities of E. coli to gamma-rays not only at room temperature but also at deep frozen conditions. These phenomena were elucidated by the decrease of production and mobility of OH radicals at deep frozen conditions. (author)

  11. Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

    OpenAIRE

    Abdelazez, Amro; Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao; Abdelmotaal, Heba; Sami, Rokayya; Meng, Xiang-Chen

    2017-01-01

    Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adoles...

  12. Verification of the validity of the short-pulse approximation for one-dimensional Rydberg atoms

    International Nuclear Information System (INIS)

    Kopyciuk, T; Grajek, M

    2011-01-01

    In this paper, we investigate the short-pulse approximation (SPA) for one-dimensional Rydberg atoms. We analyse the limits that SPA has to fulfil in order to be applicable. These concern the shape, the duration and the displacement caused by the pulse. The correctness of SPA is tested by comparing the results obtained using SPA with a numerical solution of the set of time-dependent Schroedinger equations. We show that the limit for the displacement caused by the pulse is of greatest importance. Violation of the limit for the duration of the pulse is shown to lead to concurrent violation of the limit for the displacement. We also show that the shape of the pulse has no influence on the created wave packet.

  13. Ionic Impurity in a Bose-Einstein Condensate at Submicrokelvin Temperatures

    Science.gov (United States)

    Kleinbach, K. S.; Engel, F.; Dieterle, T.; Löw, R.; Pfau, T.; Meinert, F.

    2018-05-01

    Rydberg atoms immersed in a Bose-Einstein condensate interact with the quantum gas via electron-atom and ion-atom interaction. To suppress the typically dominant electron-neutral interaction, Rydberg states with a principal quantum number up to n =190 are excited from a dense and tightly trapped micron-sized condensate. This allows us to explore a regime where the Rydberg orbit exceeds the size of the atomic sample by far. In this case, a detailed line shape analysis of the Rydberg excitation spectrum provides clear evidence for ion-atom interaction at temperatures well below a microkelvin. Our results may open up ways to enter the quantum regime of ion-atom scattering for the exploration of charged quantum impurities and associated polaron physics.

  14. VUV spectroscopy of rare gas van der Waals dimers

    International Nuclear Information System (INIS)

    Dehmer, P.M.; Pratt, S.T.

    1982-01-01

    We have undertaken a systematic study of the photoionization spectra of the homonuclear and heteronuclear rare gas dimers in order to better understand the nature of the bonding in the Rydberg states adnd ions of these molecules. We have obtained results for Ar 2 , Kr 2 , Xe 2 , NeAr, NeKr, NeXe, ArKr, ArXe, and KrXe. Of the remaining dimer species (Ne 2 and the Herare gas dimers), only Ne 2 has been studied using photoionization mass spectrometry. The results of the present series of experiments provide information both on the excited states of the neutral dimers and on the ground and excited states of the dimer ions. Using the data obtained in these measurements, we are able to compile for the first time a nearly complete list of ground state dissociation energies for the homonuclear and heteronuclear rare gas dimer ions. Somewhat less complete results are obtained for the excited states of these species. The observed trends in binding energy provide an excellent example of the systematic changes that occur as a result of changes in atomic orbital energies, polarizability, and internuclear distance, and these trends can be explained qualitatively in terms of simple molecular orbital theory

  15. Numerical modeling of frozen wave instability in fluids with high viscosity contrast

    Energy Technology Data Exchange (ETDEWEB)

    Lyubimov, D V; Ivantsov, A O; Lyubimova, T P [Theoretical Physics Department, Perm State University, Perm (Russian Federation); Khilko, G L, E-mail: lyubimovat@mail.ru [Institute of Continuous Media Mechanics UB RAS, Perm (Russian Federation)

    2016-12-15

    This paper deals with the direct numerical simulation of quasi-stationary (frozen) wave formation at the interface of two immiscible fluids with large viscosity contrast, in a rectangular container subjected to the horizontal vibrations of finite frequency and amplitude. The critical conditions for the origination of a frozen wave as well as the dependences of the frozen wave height and wavelength on the vibration intensity are obtained. The time-evolution of the interface shape during the vibration period is analyzed. Numerical results are found to be in a good agreement with known experimental and linear stability results. The average deformation of the interface and the structure of average flows are calculated for different vibration intensities. It is shown that a change in the dependencies of the frozen wave characteristics on the vibration intensity follows a change in average flow structure. (paper)

  16. Breed differences of bull frozen-thawed semen.

    Science.gov (United States)

    Ntemka, A; Tsousis, G; Brozos, C; Kiossis, E; Boscos, C M; Tsakmakidis, I A

    2016-12-01

    The objective of this study was to investigate the quality of frozen-thawed semen from different bull breeds. Commercial frozen-thawed bull semen samples (26 per breed, 130 totally) of five breeds (Holstein [Η], Brown Swiss [BS], Limousin [L], Belgian Blue [BB], Blonde d' Aquitaine [BA]) were used. After thawing, each semen sample was subjected to thermal resistance test (TR) for 0.5 and 1 hr at 38°C and hypo-osmotic swelling test (HOST) for 1 hr at 150 mOsm at 37°C. Additionally, all samples were evaluated at times 0 hr (thawing), 0.5 hr (TR), 1 hr (TR) for kinetics by CASA [progressive, immotile, rapid, medium, slow moving spermatozoa, curvilinear velocity (VCL), average path velocity (VAP), straight line velocity (VSL), linearity (LIN), straightness (STR), beat cross-frequency (BCF), amplitude of lateral head displacement (ALH), wobble (WOB)]. Moreover, directly after thawing, all semen samples were evaluated for morphometry, morphology, viability and DNA fragmentation. Statistical analysis was conducted using a mixed model for repeated measures. The results showed (a) higher VCL after thawing in H, L breeds compared to BB and BA, (b) higher VAP after thawing in L compared to BB, BA, (c) higher values of progressive spermatozoa after TR in H, BS compared to BB, BA, (d) higher values of rapid spermatozoa after thawing and 0.5 hr of TR in H, BS, L compared to BB, BA, (e) lower viability in BA after thawing compared to H, BS, BB, (f) lower morphological abnormalities in H compared to L, BB, (g) higher head length in Η compared to BB. No significant differences were observed in the results from HOST and DNA fragmentation between breeds. In conclusion, quality characteristics of frozen-thawed bull semen are dependent on the breed. Frozen semen from BB and BA breeds should be handled more carefully after thawing, as it is more sensitive to stress. © 2016 Blackwell Verlag GmbH.

  17. A STUDY ON MANAGEMENT OF ADHESIVE CAPSULITIS (FROZEN SHOULDER BY HYDRODILATATION METHOD

    Directory of Open Access Journals (Sweden)

    S. Lakshmi Narayana

    2016-08-01

    Full Text Available AIMS AND OBJECTIVES To study the efficacy of hydraulic distension under local anaesthesia in the management of frozen shoulder. To study the age and sex distribution of frozen shoulder. MATERIALS AND METHODS 50 Patients with 54 shoulders of frozen shoulder syndrome, 4 cases with bilateral shoulder involvement were studied. A detailed history was elicited with particular reference to frozen shoulder (as shown in the proforma. A preliminary general physical examination was done. RESULTS Fifty patients with 54 shoulders of frozen shoulder syndrome were treated with hydraulic distension under local anaesthesia. The maximum and minimum age in this study was found to be 85 years and 41 years respectively. The average age of the patients in this study was calculated as 54.16 years. Out of 50 patients followed up, 32 were females and 18 were males. The Female: Male ratio was 1.77:1. In this series, 4 patients had bilateral involvement. In 17 patients, side involved was the dominant that is right arm. In 29 cases, the left arm that is non-dominant arm was involved. Associated conditions in this series are 7 patients had diabetes mellitus, 4 patients had hypertension, 5 patients had osteoarthritis of knee, 2 had peptic ulcer, 1 pulmonary Koch’s and 1 had bilateral cataract. CONCLUSION Concomitant home exercises program is a must and is the hallmark of success following hydraulic distension. Hydraulic distension is a safe, reliable, cost effective without requiring specialised equipment in the management of frozen shoulder.

  18. Effects of addition of sodium lauryl sulfate on frozen-thawed canine spermatozoa.

    Science.gov (United States)

    Hori, Tatsuya; Kaseki, Hanae; Fukuhara, Youko; Oba, Hiromichi; Mizutani, Tatsuji; Kawakami, Eiichi; Tsutsui, Toshihiko

    2006-10-01

    The addition of Orvus ES paste (OEP) to extender may be essential for preparing frozen dog semen. The major ingredient of OEP is sodium lauryl sulfate (SLS). In this study, we compared the effect of SLS on frozen dog semen with that of OEP. There were no significant differences between the 2-mg/ml SLS group and OEP group concerning sperm motility, viability and the percentage of viable sperm with intact acrosomes after freeze-thawing. These results suggest that the effectiveness of frozen dog semen extender containing 2 mg/ml of SLS is similar effective to that demonstrated for OEP.

  19. Exploring the outcomes in studies of primary frozen shoulder

    DEFF Research Database (Denmark)

    Rodgers, Sara; Brealey, Stephen; Jefferson, Laura

    2014-01-01

    PURPOSE: In our study we explored the need to define a core outcome set for primary frozen shoulder. METHODS: We investigated the outcomes used by studies included in a systematic review of the management of primary frozen shoulder; surveyed which primary outcome measures health care professionals...... and 104 respondents, respectively) were most often cited by health care professionals as the primary outcome measure that should be used. Searches identified one paper that included patients' views. Outcomes of importance to patients were pain at night, general pain, reduced mobility (resulting...

  20. THE INFLUENCE OF MICROWAVE OVENS ON THE DEMAND FOR FRESH AND FROZEN POTATOES

    OpenAIRE

    Guenthner, Joseph F.; Lin, Biing-Hwan; Levi, Annette E.

    1991-01-01

    Growth in the number of homes with microwave ovens has changed food preferences and preparation methods. The objective of this study was to determine the impact that microwave oven ownership has had on the demand for fresh and frozen potatoes. Using data from the 1970-88 period, demand equations were estimated for fresh potatoes, frozen potatoes in the retail market and frozen potatoes in the food service market. Results indicate that increases in the percentage of homes that own microwave ov...

  1. Clinical outcomes after arthroscopic release for recalcitrant frozen shoulder.

    Science.gov (United States)

    Ebrahimzadeh, Mohammad H; Moradi, Ali; Pour, Mostafa Khalili; Moghadam, Mohammad Hallaj; Kachooei, Amir Reza

    2014-09-01

    To explain the role of arthroscopic release in intractable frozen shoulders. We used different questionnaires and measuring tools to understand whether arthroscopic release is the superior modality to treat patients with intractable frozen shoulders. Between 2007 and 2013, in a prospective study, we enrolled 80 patients (52 females and 28 males) with recalcitrant frozen shoulder, who underwent arthroscopic release at Ghaem Hospital, a tertiary referral center, in Mashhad, Iran. Before operation, all patients filled out the Disability of Arm, Shoulder and Hand (DASH), Constant, University of California Los Angeles (UCLA), ROWE and Visual Analogue Scale (VAS) for pain questionnaires. We measured the difference in range of motion between both the normal and the frozen shoulders in each patient. The average age of the patients was 50.8±7.1 years. In 49 patients, the right shoulder was affected and in the remaining 31 the left side was affected. Before surgery, the patients were suffering from this disease on average for 11.7±10.3 months. The average time to follow-up was 47.2±6.8 months (14 to 60 months). Diabetes mellitus (38%) and history of shoulder trauma (23%) were the most common comorbidities in our patients. We did not find any significant differences between baseline characteristics of diabetics patients with non-diabetics ones. After surgery, the average time to achieve maximum pain improvement and range of motion were 3.6±2.1 and 3.6±2 months, respectively. The VAS score, constant shoulder score, Rowe score, UCLA shoulder score, and DASH score showed significant improvement in shoulder function after surgery, and shoulder range of motion improved in all directions compared to pre-operation range of motion. According to our results, arthroscopic release of recalcitrant frozen shoulder is a valuable modality in treating this disease. This method could decrease pain and improve both subjective and objective mid-term outcomes.

  2. Clinical Outcomes after Arthroscopic Release for Recalcitrant Frozen Shoulder

    Directory of Open Access Journals (Sweden)

    Mohammad Hosein Ebrahimzadeh

    2014-09-01

    Full Text Available Background: To explain the role of arthroscopic release in intractable frozen shoulders. We used different questionnaires and measuring tools to understand whether arthroscopic release is the superior modality to treat patients with intractable frozen shoulders. Methods: Between 2007 and 2013, in a prospective study, we enrolled 80 patients (52 females and 28 males with recalcitrant frozen shoulder, who underwent arthroscopic release at Ghaem Hospital, a tertiary referral center, in Mashhad, Iran. Before operation, all patients filled out the Disability of Arm, Shoulder and Hand (DASH, Constant, University of California Los Angeles (UCLA, ROWE and Visual Analogue Scale (VAS for pain questionnaires. We measured the difference in range of motion between both the normal and the frozen shoulders in each patient. Results: The average age of the patients was 50.8±7.1 years. In 49 patients, the right shoulder was affected and in the remaining 31 the left side was affected. Before surgery, the patients were suffering from this disease on average for 11.7±10.3 months.  The average time to follow-up was 47.2±6.8 months (14 to 60 months. Diabetes mellitus (38% and history of shoulder trauma (23% were the most common comorbidities in our patients. We did not find any significant differences between baseline characteristics of diabetics patients with non-diabetics ones. After surgery, the average time to achieve maximum pain improvement and range of motion were 3.6±2.1 and 3.6±2 months, respectively. The VAS score, constant shoulder score, Rowe score, UCLA shoulder score, and DASH score showed significant improvement in shoulder function after surgery, and shoulder range of motion improved in all directions compared to pre-operation range of motion. Conclusions: According to our results, arthroscopic release of recalcitrant frozen shoulder is a valuable modality in treating this disease. This method could decrease pain and improve both subjective and

  3. Effect of fructo-oligosaccharide and isomalto-oligosaccharide addition on baking quality of frozen dough.

    Science.gov (United States)

    Park, Eun Young; Jang, Sung-Bum; Lim, Seung-Taik

    2016-12-15

    The baking quality of frozen doughs containing different levels of fructo-oligosaccharides (FO) or isomalto-oligosaccharides (IMO) (3-9%, w/w flour), and stored for 0-8weeks at -18°C, was examined. The addition of FO or IMO increased the proof volume of the dough and the loaf volume of bread prepared from frozen dough. A 6% addition of FO or IMO was optimum, giving the highest proof volume and bread loaf volume, but a higher concentration than 6% induced low baking quality including lower proof volume and bread loaf volume. The bread crumb was moister and softer after the addition of FO or IMO before, and even after, frozen storage. Darker crumb colour was observed in the bread after the addition of FO or IMO. The oligosaccharides added to the frozen dough were effective in improving the quality of bread made from frozen dough, except for resulting in a darker bread crumb. Copyright © 2016. Published by Elsevier Ltd.

  4. Photochemical processing of aldrin and dieldrin in frozen aqueous solutions under arctic field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, Glenn A.; Bausch, Alexandra R. [Department of Chemistry, Villanova University, Villanova, PA 19085 (United States); Grannas, Amanda M., E-mail: amanda.grannas@villanova.edu [Department of Chemistry, Villanova University, Villanova, PA 19085 (United States)

    2011-05-15

    Organochlorine (OC) contaminants are transported to the Polar Regions, where they have the potential to bioaccumulate, presenting a threat to the health of wildlife and indigenous communities. They deposit onto snowpack during winter, and accumulate until spring, when they experience prolonged solar irradiation until snowmelt occurs. Photochemical degradation rates for aldrin and dieldrin, in frozen aqueous solution made from MilliQ water, 500 {mu}M hydrogen peroxide solution or locally-collected melted snow were measured in a field campaign near Barrow, AK, during spring-summer 2008. Significant photoprocessing of both pesticides occurs; the reactions depend on temperature, depth within the snowpack and whether the predominant phase is ice or liquid water. The effect of species present in natural snowpack is comparable to 500 {mu}M hydrogen peroxide, pointing to the potential significance of snowpack-mediated reactions. Aldrin samples frozen at near 0 deg. C were more reactive than comparable liquid samples, implying that the microenvironments experienced on frozen ice surfaces are an important consideration. - Highlights: > Photodegradation rates for aldrin and dieldrin in frozen aqueous solutions made from MilliQ water, H{sub 2}O{sub 2} or melted snow are reported. > Photoprocessing depends on temperature, depth beneath the snowpack surface and dominant phase. > Species present in natural snowpack have a photosensitizing effect comparable to 500 {mu}M H{sub 2}O{sub 2}. > Aldrin samples frozen at near 0 deg. C were more reactive than comparable liquid samples. > Collectively we find that frozen aqueous surfaces play a unique role in aldrin and dieldrin photochemistry. - A field study finds that frozen aqueous solutions of aldrin and dieldrin undergo photochemical degradation under arctic snowpack conditions. The reactions are enhanced in frozen systems and by natural snowpack constituents.

  5. Xanthogranuloma of the sellar region diagnosed by frozen section

    Directory of Open Access Journals (Sweden)

    Ji Kun

    2016-01-01

    Full Text Available Xanthogranuloma (XG of the sellar region is uncommon and is difficult to diagnose based on intraoperative frozen sections. This study is a case presentation and review of the literature, highlighting the need to explore underlying diseases in order to guarantee an accurate patient diagnosis. Herein, we presented the case of a 43-year-old woman who was afflicted with xanthogranuloma of the sellar region; the patient had a history of headache and lengthened menstrual cycles over the 6 months prior to presentation. Endocrinology tests revealed that the patient’s levels of prolactin were high and the MRI of the patient showed a clearly defined sellar mass. As a result, the patient was considered to have prolactinoma prior to undergoing surgery. The tumor was completely removed using a transsphenoidal approach, and intraoperative frozen section revealed histology similar to xanthogranuloma. When the tumor was removed by surgical operation, the patient’s visual field defects and headache were relieved. Although intraoperative frozen section should provide some guidance with regard to the diagnosis, a pathological study is conducted to confirm the actual diagnosis.

  6. A new frozen-spin target for 4π particle detection

    International Nuclear Information System (INIS)

    Bradtke, Ch.; Dutz, H.; Peschel, H.; Goertz, S.; Harmsen, J.; Hasegawa, S.; Horikawa, N.; Iwata, T.; Kageya, T.; Matsuda, T.; Meier, A.; Meyer, W.; Radtke, E.; Reicherz, G.; Rohlof, Ch.; Thomas, A.; Wakai, A.

    1999-01-01

    A new frozen-spin target has been developed, that allows the detection of emitted particles in an angular acceptance of almost 4π in the laboratory frame. The central part of this new target represents a 3 He/ 4 He dilution refrigerator that is installed horizontally along the beam axis. The refrigerator includes an internal superconducting holding coil to maintain the nucleon polarization in the frozen-spin mode longitudinally to the beam. The design of the dilution refrigerator and the use of an internal holding coil enabled for the first time the measurement of a spin-dependent total cross section in combination with a polarized solid state target. This new frozen-spin target was used successfully to measure the helicity asymmetry of the total photoabsorption cross-section at the Mainz accelerator facility MAMI. This experiment has been performed in order to verify for the first time the GDH sum rule

  7. Laboratory determination of the infrared band strengths of pyrene frozen in water ice: Implications for the composition of interstellar ices

    Energy Technology Data Exchange (ETDEWEB)

    Hardegree-Ullman, E. E. [New York Center for Astrobiology and Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States); Gudipati, M. S.; Werner, M. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Boogert, A. C. A. [Infrared Processing and Analysis Center, Mail Code 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Lignell, H. [Department of Chemistry, University of California Irvine, Irvine, CA 92697-2025 (United States); Allamandola, L. J. [Space Science Division, Mail Stop 245-6, NASA Ames Research Center, Moffett Field, CA 94035 (United States); Stapelfeldt, K. R., E-mail: hardee@rpi.edu, E-mail: gudipati@jpl.nasa.gov [NASA Goddard Space Flight Center, Exoplanets and Stellar Astrophysics Laboratory, Code 667, Greenbelt, MD 20771 (United States)

    2014-04-01

    Broad infrared emission features (e.g., at 3.3, 6.2, 7.7, 8.6, and 11.3 μm) from the gas phase interstellar medium have long been attributed to polycyclic aromatic hydrocarbons (PAHs). A significant portion (10%-20%) of the Milky Way's carbon reservoir is locked in PAH molecules, which makes their characterization integral to our understanding of astrochemistry. In molecular clouds and the dense envelopes and disks of young stellar objects (YSOs), PAHs are expected to be frozen in the icy mantles of dust grains where they should reveal themselves through infrared absorption. To facilitate the search for frozen interstellar PAHs, laboratory experiments were conducted to determine the positions and strengths of the bands of pyrene mixed with H{sub 2}O and D{sub 2}O ices. The D{sub 2}O mixtures are used to measure pyrene bands that are masked by the strong bands of H{sub 2}O, leading to the first laboratory determination of the band strength for the CH stretching mode of pyrene in water ice near 3.25 μm. Our infrared band strengths were normalized to experimentally determined ultraviolet band strengths, and we find that they are generally ∼50% larger than those reported by Bouwman et al. based on theoretical strengths. These improved band strengths were used to reexamine YSO spectra published by Boogert et al. to estimate the contribution of frozen PAHs to absorption in the 5-8 μm spectral region, taking into account the strength of the 3.25 μm CH stretching mode. It is found that frozen neutral PAHs contain 5%-9% of the cosmic carbon budget and account for 2%-9% of the unidentified absorption in the 5-8 μm region.

  8. 77 FR 73424 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Partial Rescission of...

    Science.gov (United States)

    2012-12-10

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... order on certain frozen fish fillets (``fish fillets'') from the Socialist Republic of Vietnam..., 2011. \\1\\ See Notice of Antidumping Duty Order: Certain Frozen Fish Fillets from the Socialist Republic...

  9. 78 FR 40100 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Rescission of Antidumping...

    Science.gov (United States)

    2013-07-03

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... frozen fish fillets from the Socialist Republic of Vietnam (``Vietnam'') covering the period August 1... Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Initiation of Antidumping Duty New...

  10. Frozen shoulder : long-term outcome following arthrographic distension.

    Science.gov (United States)

    Clement, Rhys G E; Ray, Andrew G; Davidson, Colin; Robinson, C Mike; Perks, Fergus J

    2013-08-01

    Arthrographic distension of the glenohumeral joint was adopted as a mainstream treatment for frozen shoulder before any randomised controlled trials were performed. Interpretation of the effectiveness of this procedure rests mostly on data from cohort studies of which there are few of high quality. Papers reporting long-term results have either excluded diabetic patients or failed to report patient orientated outcomes. The authors present a long-term prospective cohort study of 51 patients (12 diabetics and 39 non-diabetics), with 53 frozen shoulders, who had an arthrographic distension performed by a single radiologist as a primary intervention. Oxford shoulder score (OSS), visual analogue pain score (VAS), and range of movement (ROM) were recorded pre-distension, at 2 days and 1 month post-distension. OSS and VAS were recorded again at a mean of 14 months post distension (range : 8-26 months). OSS improved from a pre-distension mean of 22.3 by 16.9 points at final follow-up (p diabetic patients was the same as in non-diabetic patients. Arthrographic distension is a safe and effective treatment for frozen shoulder; it is also effective in diabetic patients. It gives long-term improvement. The authors believe that the low number of patients requiring a secondary procedure makes arthrographic distension preferable to manipulation under anaesthesia.

  11. Interference effects at photoionization of Rydberg atoms by a strong electromagnetic field

    International Nuclear Information System (INIS)

    Movsesyan, A.M.; Fedorov, M.V.

    1989-01-01

    The photoionization of Rydberg atoms in a strong electromagnetic field is considered. Degeneration of the levels with respect to the orbital moment, their Stark splitting and the possibility of resonant interaction with levels of lower energy are taken into account. The complex quasi-energies of the system, photoelectron spectrum in the limit of an infinite duration of interaction and the time dependence of the total ionization probability are found. It is shown that a narrowing of the quasi-energy levels occurs in a strong field. Against a background of the quasi- continuum the quasi-energy spectrum consists of more or less narrow levels. In this case the photoelectron spectrum acquires a multi-peak form. With increasing field strength the height of the peaks increases, whereas their width decreases. The ionization rate decreases with increasing field strength. The presence of a quasi-continuum is the cause of the partially non-exponential nature of the atomic disintegration

  12. Absolute high-resolution Se+ photoionization cross-section measurements with Rydberg-series analysis

    International Nuclear Information System (INIS)

    Esteves, D. A.; Bilodeau, R. C.; Sterling, N. C.; Phaneuf, R. A.; Kilcoyne, A. L. D.; Red, E. C.; Aguilar, A.

    2011-01-01

    Absolute single photoionization cross-section measurements for Se + ions were performed at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory using the photo-ion merged-beams technique. Measurements were made at a photon energy resolution of 5.5 meV from 17.75 to 21.85 eV spanning the 4s 2 4p 3 4 S 3/2 o ground-state ionization threshold and the 2 P 3/2 o , 2 P 1/2 o , 2 D 5/2 o , and 2 D 3/2 o metastable state thresholds. Extensive analysis of the complex resonant structure in this region identified numerous Rydberg series of resonances and obtained the Se 2+ 4s 2 4p 23 P 2 and 4s 2 4p 21 S 0 state energies. In addition, particular attention was given to removing significant effects in the measurements due to a small percentage of higher-order undulator radiation.

  13. Comparison of the target-thickness dependence of the convoy electron yield and the Rydberg electron yield measured in coincidence with exit charge states in fast ion-solid collisions

    International Nuclear Information System (INIS)

    Gaither, C.C. III; Breinig, M.; Freyou, J.; Underwood, T.A.

    1988-01-01

    We have simultaneously measured the yield of convoy electrons and the yield of electrons in high Rydberg states of the projectile (n /approx gt/ 70), produced by 2MeV/u C projectiles passing through C foils, whose thicknesses range from 4--10 ug/cm 2 , for incident charge states q/sub i/ = 4--6 and exit charge states q/sub e/ = 4--6. We have found that these yields exhibit similar trends as a function of foil thickness, but that, nevertheless, the ratio of the number of convoy electrons detected in coincidence with ions of exit charge state q/sub e/ to the number of electrons detected in high Rydberg states of ions with the same exit charge state is a function of foil thickness. This may be due to a broadening of the convoy electron energy spectrum with increasing foil thickness. 6 refs., 3 figs

  14. 77 FR 20008 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Initiation of Antidumping...

    Science.gov (United States)

    2012-04-03

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... four new shipper reviews (``NSRs'') of the antidumping duty order on certain frozen fish fillets... Antidumping Duty Order: Certain Frozen Fish Fillets From the Socialist Republic of Vietnam, 68 FR 47909...

  15. Deutsch, Toffoli, and cnot Gates via Rydberg Blockade of Neutral Atoms

    Science.gov (United States)

    Shi, Xiao-Feng

    2018-05-01

    Universal quantum gates and quantum error correction (QEC) lie at the heart of quantum-information science. Large-scale quantum computing depends on a universal set of quantum gates, in which some gates may be easily carried out, while others are restricted to certain physical systems. There is a unique three-qubit quantum gate called the Deutsch gate [D (θ )], from which a circuit can be constructed so that any feasible quantum computing is attainable. We design an easily realizable D (θ ) by using the Rydberg blockade of neutral atoms, where θ can be tuned to any value in [0 ,π ] by adjusting the strengths of external control fields. Using similar protocols, we further show that both the Toffoli and controlled-not gates can be achieved with only three laser pulses. The Toffoli gate, being universal for classical reversible computing, is also useful for QEC, which plays an important role in quantum communication and fault-tolerant quantum computation. The possibility and speed of realizing these gates shed light on the study of quantum information with neutral atoms.

  16. The Excitation of Rydberg Atoms of Thallium in an Electric Field

    Science.gov (United States)

    Bokhan, P. A.; Zakrevskii, D. E.; Kim, V. A.; Fateev, N. V.

    2018-01-01

    The spectrum of excitation of Rydberg states of thallium atoms has been investigated using a collimated atomic beam in a two-step isotope selective laser scheme 62 P 1/2 → 62 D 3/2 → Tl** in the presence of an electric field with a strength of up to 1.5 kV/cm near the level 16 F 5/2. The optical transitions 6 D 3/2 → 18 D 3/2 and 6 D 3/2 → 16 G 7/2, which were induced by an external electric field and dipole-forbidden, have been studied experimentally. The values for the scalar polarizabilities (in units cm-1/(kV/cm)2) α0(16 F 5/2) = 3.71 ± 0.3, α0(18 D 3/2) = 11.70 ± 0.25, and α0(16 G 7/2) = 44.1 ± 0.9, which are compared with the calculated one, have been obtained. The new values of energy parameters for the states 18 D 3/2 and 16 G 7/2 have been determined.

  17. Sewage Effluent Infiltrates Frozen Forest Soil

    Science.gov (United States)

    Alfred Ray Harris

    1976-01-01

    Secondarily treated sewage effluent, applied at the rate of 1 and 2 inches per week, infiltrated a frozen Sparta sand soil forested with jack pine and scrub oak. Maximum frost depth in treated plots averaged 60 cm and in check plots averages 35 cm. Nitrogen was mobile with some accumulation. Phosphorus was absorbed.

  18. HPTAM, a two-dimensional Heat Pipe Transient Analysis Model, including the startup from a frozen state

    Science.gov (United States)

    Tournier, Jean-Michel; El-Genk, Mohamed S.

    1995-01-01

    A two-dimensional Heat Pipe Transient Analysis Model, 'HPTAM,' was developed to simulate the transient operation of fully-thawed heat pipes and the startup of heat pipes from a frozen state. The model incorporates: (a) sublimation and resolidification of working fluid; (b) melting and freezing of the working fluid in the porous wick; (c) evaporation of thawed working fluid and condensation as a thin liquid film on a frozen substrate; (d) free-molecule, transition, and continuum vapor flow regimes, using the Dusty Gas Model; (e) liquid flow and heat transfer in the porous wick; and (f) thermal and hydrodynamic couplings of phases at their respective interfaces. HPTAM predicts the radius of curvature of the liquid meniscus at the liquid-vapor interface and the radial location of the working fluid level (liquid or solid) in the wick. It also includes the transverse momentum jump condition (capillary relationship of Pascal) at the liquid-vapor interface and geometrically relates the radius of curvature of the liquid meniscus to the volume fraction of vapor in the wick. The present model predicts the capillary limit and partial liquid recess (dryout) in the evaporator wick, and incorporates a liquid pooling submodel, which simulates accumulation of the excess liquid in the vapor core at the condenser end.

  19. Experimental research of joint influence of salinization and petroleum pollution on thermal capacity of frozen ground

    International Nuclear Information System (INIS)

    Motenko, R.G.

    2010-01-01

    Most gas and petroleum fields are located in permafrost zones, with some being on saline territories. Oil pollution of soils can occur in different ways and at different points such as during the extraction, processing and storage, and during transportation of oil and petroleum products. Oil producing pollution and salinization of soil often happen together. In this case, the sources of salts are the formation fluid, commercial waste water, the contents of the granaries and other geochemically active substances used for the extraction and desalting of crude oil. Joint salinization and contamination can also happen during the rupture of oil pipelines in saline areas. Although there is research available on the properties of saline soils and on properties of soils polluted with petroleum, there are no studies that describe changes of ground properties with joint pollution of salt and petroleum. This paper presented a study that examined the joint influence of salinization and petroleum pollution on the thermal characteristics of thawed and frozen grounds, particularly on thermal capacity. The paper outlined the purpose of the research and described the experimental methods. It was concluded that an increase of salinization increases the heat capacity of frozen soil because the amount of unfrozen water increases with increasing salinization. 10 refs., 5 figs.

  20. Experimental research of joint influence of salinization and petroleum pollution on thermal capacity of frozen ground

    Energy Technology Data Exchange (ETDEWEB)

    Motenko, R.G. [Moscow State Univ., Moscow (Russian Federation). Dept. of Geocryology; Grechishcheva, E.S. [Fundamentproek, Moscow (Russian Federation)

    2010-07-01

    Most gas and petroleum fields are located in permafrost zones, with some being on saline territories. Oil pollution of soils can occur in different ways and at different points such as during the extraction, processing and storage, and during transportation of oil and petroleum products. Oil producing pollution and salinization of soil often happen together. In this case, the sources of salts are the formation fluid, commercial waste water, the contents of the granaries and other geochemically active substances used for the extraction and desalting of crude oil. Joint salinization and contamination can also happen during the rupture of oil pipelines in saline areas. Although there is research available on the properties of saline soils and on properties of soils polluted with petroleum, there are no studies that describe changes of ground properties with joint pollution of salt and petroleum. This paper presented a study that examined the joint influence of salinization and petroleum pollution on the thermal characteristics of thawed and frozen grounds, particularly on thermal capacity. The paper outlined the purpose of the research and described the experimental methods. It was concluded that an increase of salinization increases the heat capacity of frozen soil because the amount of unfrozen water increases with increasing salinization. 10 refs., 5 figs.

  1. 75 FR 22370 - Certain Frozen Warmwater Shrimp From Brazil, Ecuador, India, the People's Republic of China...

    Science.gov (United States)

    2010-04-28

    ...-893, A-549-822, A-552-802] Certain Frozen Warmwater Shrimp From Brazil, Ecuador, India, the People's... certain frozen warmwater shrimp from Brazil, Ecuador, India, the People's Republic of China, Thailand, and... Frozen and Canned Warmwater Shrimp From Ecuador, 69 FR 76913 (December 23, 2004) (Ecuador Final...

  2. Light in Condensed Matter in the Upper Atmosphere as the Origin of Homochirality: Circularly Polarized Light from Rydberg Matter

    Science.gov (United States)

    Holmlid, Leif

    2009-08-01

    Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

  3. Light in condensed matter in the upper atmosphere as the origin of homochirality: circularly polarized light from Rydberg matter.

    Science.gov (United States)

    Holmlid, Leif

    2009-01-01

    Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

  4. A new frozen-spin target for 4 pi particle detection

    CERN Document Server

    Bradtke, C; Peschel, H; Görtz, S; Harmsen, J; Hasegawa, S; Horikawa, N; Iwata, T; Kageya, T; Matsuda, T; Meier, A; Meyer, Werner T; Radtke, E; Reicherz, G; Rohlof, C; Thomas, A; Wakai, A

    1999-01-01

    A new frozen-spin target has been developed, that allows the detection of emitted particles in an angular acceptance of almost 4 pi in the laboratory frame. The central part of this new target represents a sup 3 He/ sup 4 He dilution refrigerator that is installed horizontally along the beam axis. The refrigerator includes an internal superconducting holding coil to maintain the nucleon polarization in the frozen-spin mode longitudinally to the beam. The design of the dilution refrigerator and the use of an internal holding coil enabled for the first time the measurement of a spin-dependent total cross section in combination with a polarized solid state target. This new frozen-spin target was used successfully to measure the helicity asymmetry of the total photoabsorption cross-section at the Mainz accelerator facility MAMI. This experiment has been performed in order to verify for the first time the GDH sum rule.

  5. The infrared spectral properties of frozen volatiles. [in cometary nuclei

    Science.gov (United States)

    Fink, U.; Sill, G. T.

    1982-01-01

    Since Whipple's dirty snowball model of comet nuclei, it has been generally accepted that volatile ices help to explain cometary phenomena. The infrared spectral properties of many substances that are potential candidates for frozen volatiles in the solar system are being pursued; indeed some of these frozen materials have been found in the solar system: H2O, CO2, and SO2. A review of laboratory spectra in the range 1 to 20 microns of H2O, CO2, SO2, CH4, NH3, H2S, CO, NH4HS and NH3.H2O is presented. Both reflection spectra of thick frosts and transmission spectra of thin films are shown, and their main characteristics are described. Hydrates, clathrates, and composite spectra are discussed. When it is possible to observe the nuclei of comets at close range, it may be possible to identify frozen volatiles by their infrared spectra.

  6. Static equilibria of the interstellar gas in the presence of magnetic and gravitational fields

    International Nuclear Information System (INIS)

    Mouschovias, T.C.

    1975-01-01

    No exact self-consistent equilibrium calculations exist for (any model of) the system of the interstellar gas and the frozen-in magnetic field. On a large scale (approximately 1 kpc) this system is affected by the vertical galactic gravitational field, while on a small scale (approximately 1 pc) the self-gravitation of the gas comes into play and is responsible for the collapse of some clouds to form stars. Accessible equilibrium states are determined for the gas--field system on both of these scales. (U.S.)

  7. Temporal Bell-type inequalities for two-level Rydberg atoms coupled to a high-Q resonator

    International Nuclear Information System (INIS)

    Huelga, S.F.; Marshall, T.W.; Santos, E.

    1996-01-01

    Following the strategy of showing specific quantum effects by means of the violation of a classical inequality, a pair of Bell-type inequalities is derived on the basis of certain additional assumptions, whose plausibility is discussed in detail. Such inequalities are violated by the quantum mechanical predictions for the interaction of a two-level Rydberg atom with a single mode sustained by a high-Q resonator. The experimental conditions required in order to show the existence of forbidden values, according to a hidden variables formalism, in a real experiment are analyzed for various initial field statistics. In particular, the revival dynamics expected for the interaction with a coherent field leads to classically forbidden values, which would indicate a purely quantum effect. copyright 1996 The American Physical Society

  8. Successful artificial insemination in the Asian elephant (Elephas maximus using chilled and frozen-thawed semen

    Directory of Open Access Journals (Sweden)

    Wongkalasin Warut

    2009-07-01

    Full Text Available Abstract Background Artificial insemination (AI using frozen-thawed semen is well established and routinely used for breeding in various mammalian species. However, there is no report of the birth of elephant calves following AI with frozen-thawed semen. The objective of the present study was to investigate the fertilizing ability of chilled and frozen-thawed semen in the Asian elephant following artificial insemination (AI. Methods Semen samples were collected by from 8 bulls (age range, 12-to 42-years by manual stimulation. Semen with high quality were either cooled to 4°C or frozen in liquid nitrogen (-196°C before being used for AI. Blood samples collected from ten elephant females (age range, 12-to 52-years were assessed for estrus cycle and elephants with normal cycling were used for AI. Artificial insemination series were conducted during 2003 to 2008; 55 and 2 AI trials were conducted using frozen-thawed and chilled semen, respectively. Pregnancy was detected using transrectal ultrasonography and serum progestagen measurement. Results One female (Khod inseminated with chilled semen became pregnant and gave birth in 2007. The gestation length was 663 days and the sex of the elephant calf was male. One female (Sao inseminated with frozen-thawed semen showed signs of pregnancy by increasing progestagen levels and a fetus was observed for 5 months by transrectal ultrasonography. Conclusion This is the first report showing pregnancy following AI with frozen-thawed semen in the Asian elephant. Successful AI in the Asian elephant using either chilled or frozen-thawed semen is a stepping stone towards applying this technology for genetic improvement of the elephant population.

  9. The diabetic frozen shoulder: arthroscopic release.

    Science.gov (United States)

    Ogilvie-Harris, D J; Myerthall, S

    1997-02-01

    Seventeen patients who were diabetics developed frozen shoulders which failed to respond to conservative management. They had persistent pain, stiffness, and limited function. An arthroscopic release was performed by progressively releasing the anterior structures from superior to inferior. Starting from the interval area we progressed to the anterior superior glenohumeral ligament, the intra-articular portion of the subscapularis, the anterior capsule, and the inferior capsule. Postoperatively physiotherapy was carried out daily to maintain the range of movement. At a follow up of 1 to 5 years the patients were assessed using the American Shoulder Society scheme. In addition the patients were assessed preoperatively and postoperatively on four criteria; pain, external rotation, abduction, and function. We found that the patients were statistically significantly improved in all four categories. Thirteen of the 17 patients had no pain, full range of motion compared with the opposite side, and full function. There was one poor result with no improvement. The remaining three patients had improved but still had residual abnormalities. We consider arthroscopic release to be an effective treatment for the resistant diabetic frozen shoulder.

  10. Determination of blood cell subtype concentrations from frozen whole blood samples using TruCount beads.

    Science.gov (United States)

    Langenskiöld, Cecilia; Mellgren, Karin; Abrahamsson, Jonas; Bemark, Mats

    2016-06-24

    In many studies it would be advantageous if blood samples could be collected and analyzed using flow cytometry at a later stage. Ideally, sample collection should involve little hands-on time, allow for long-term storage, and minimally influence the samples. Here we establish a flow cytometry antibody panel that can be used to determine granulocytes, monocytes, and lymphocyte subset concentrations in fresh and frozen whole blood using TruCount technology. The panel can be used on fresh whole-blood samples as well as whole-blood samples that have been frozen after mixing with 10% DMSO. Concentrations in frozen and fresh sample is highly correlated both when frozen within 4 h and the day after collection (r ≥ 0.98), and the estimated concentration in frozen samples was between 91 and 94% of that in fresh samples for all cell types. Using this method whole-blood samples can be frozen using a simple preparation method, and stored long-term before accurate determination of cell concentration. This allows for standardized analysis of the samples at a reference laboratory in multi-center studies. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

  11. Studies on Rapidly Frozen Suspensions of Yeast Cells by Differential Thermal Analysis and Conductometry

    Science.gov (United States)

    Mazur, Peter

    1963-01-01

    Few, if any, yeast cells survived rapid cooling to -196°C and subsequent slow warming. After rapid freezing, the suspensions absorbed latent heat of fusion between -15° and 0°C during warming, and the relation between the amount of heat absorbed and the concentration of cells was the same as that in equivalent KCl solutions, indicating that frozen suspensions behave thermally like frozen solutions. The amount of heat absorbed was such that more than 80 per cent of the intracellular solution had to be frozen. The conductometric behavior of frozen suspensions showed that cell solutes were still inside the cells and surrounded by an intact cell membrane at the time heat was being absorbed. Two models are consistent with these findings. The first assumes that intracellular freezing has taken place; the second that all freezable water has left the cells and frozen externally. The latter model is ruled out because rapidly cooled cells do not shrink by an amount equal to the volume of water that would have to be withdrawn to prevent internal freezing. PMID:13934216

  12. Toxicity potential of residual ethylene oxide on fresh or frozen embryos maintained in plastic straws.

    Science.gov (United States)

    Schiewe, M C; Schmidt, P M; Pontbriand, D; Wildt, D E

    1988-01-01

    The toxic effects of residual ethylene oxide (EtO), a frequently used gas-sterilant, on embryos either frozen for long-term purposes or stored acutely for 30 min to 9 hr in a fresh condition in 0.25-ml straw containers were evaluated. In Experiment 1, fresh embryos were frozen (using conventional technology) in straws previously aerated for 0 hr to 8 mo after EtO sterilization. With the exception of the 8-mo group in which survival and quality ratings were depressed, embryo viability was not affected significantly by short-term prefreeze and post-thaw exposure to EtO residues. Experiment 2 was conducted to analyze the influence of prefreeze exposure to EtO residues on embryo development in vitro for embryos temporarily stored in previously sterilized straws aerated for different intervals. Compared to non-EtO-sterilized control straws, the development, quality, and viability of embryos exposed to EtO-treated straws were compromised (p less than 0.05) as the aeration interval decreased and the exposure interval increased. The combined results of both experiments indicate that EtO-treated straws can be used to cryopreserve gametes efficiently, but only if the aeration interval is greater than or equal to 72 hr and the prefreeze duration of exposure is less than or equal to 3 hr.

  13. A study on the performance of an electrostatic focusing mirror for Rydberg positronium

    Science.gov (United States)

    Jones, Adric C. L.; Cecchini, Gabriel G.; Moxom, Jeremy; Osorno, Kevin; Rutbeck-Goldman, Harris J.; Fuentes-Garcia, Melina; Greaves, Rod G.; Adams, Daniel J.; Tom, Harry W. K.; Mills, Allen P., Jr.

    2018-01-01

    Recently, we demonstrated an electrostatic mirror that focuses a beam of Rydberg positronium atoms over a 6 m path to a 32 ± 1 mm FWHM diameter spot on a position sensitive detector. The mirror is comprised of 360 wires arranged in the shape of a nearly-cylindrical revolved truncated ellipse 96 mm in radius, with potentials of equal and opposite magnitude applied to alternating wires to create a short-ranged electric field that decreases in magnitude exponentially with e-folding length = 0.53 mm. Here, we explore in detail the observed resolution and discuss the factors contributing to its broadening from the ideal point focus of a perfect embodiment of the mirror. Improvements to the design are considered, with the aim to achieve a mirror with a resolution of <0.5 mm, which is necessary for a proposed measurement of the gravitational deflection of positronium.

  14. 75 FR 22424 - Frozen Warmwater Shrimp From Brazil, China, India, Thailand, and Vietnam

    Science.gov (United States)

    2010-04-28

    ... Warmwater Shrimp From Brazil, China, India, Thailand, and Vietnam AGENCY: United States International Trade... antidumping duty orders on frozen warmwater shrimp from Brazil, China, India, Thailand, and Vietnam. SUMMARY... duty orders on frozen warmwater shrimp from Brazil, China, India, Thailand, and Vietnam would be likely...

  15. Using Disney's "Frozen" to Motivate Mathematics: Bringing Fractals into the Classroom

    Science.gov (United States)

    Piatek-Jimenez, Katrina; Phelps, Christine M.

    2016-01-01

    The movie "Frozen" took the world by storm and this global popularity of the movie and its music can be harnessed by teachers of mathematics. This article builds on the "frozen fractal" lyric from "Let It Go" to incorporate fractal geometry into primary mathematics classrooms.

  16. A Limited Survey of Heavy Metal Concentrations in Fresh and Frozen Cuttlefish Ink and Mantle Used As Food.

    Science.gov (United States)

    Conficoni, Daniele; Alberghini, Leonardo; Bissacco, Elisa; Contiero, Barbara; Giaccone, Valerio

    2018-02-01

    Cuttlefish ink is consumed as a delicacy worldwide. The current study is the first assessment of heavy metal concentrations in cuttlefish ink versus mantle under different storage methods. A total of 212 samples (64 of fresh mantle, 42 of frozen mantle, 64 of fresh ink, and 42 of frozen ink) were analyzed for the detection of the following heavy metals: arsenic (As), chromium (Cr), iron (Fe), lead (Pb), mercury (Hg), and cadmium (Cd). The median As concentrations were 12.9 mg/kg for fresh mantle, 8.63 mg/kg for frozen mantle, 10.8 mg/kg for frozen ink, and 0.41 mg/kg for fresh ink. The median Cr concentrations were 0.06 mg/kg for fresh mantle and frozen ink, 0.03 mg/kg for frozen mantle, and below the limit of quantification (LOQ) for fresh ink. The median Fe concentrations were 4.08 mg/kg for frozen ink, 1.51 mg/kg for fresh mantle, 0.73 mg/kg for frozen mantle, and below the LOQ for fresh ink. The median Pb concentrations of almost all samples were below the LOQ; only two frozen ink, one fresh ink, one frozen mantle, and one fresh mantle sample exceeded the limit stipulated by the European Union. The Hg concentrations were statistically similar among the four categories of samples; the median Hg concentrations were below the LOQ, and the maximum concentrations were found in frozen ink, at 1.62 mg/kg. The median Cd concentrations were 0.69 mg/kg for frozen ink and 0.11 mg/kg for frozen mantle, fresh mantle and fresh ink concentrations were below the LOQ, and in 11.3% of the tested samples, Cd concentrations were higher than the European Union limit. The probability of samples having a Cd concentration above the legal limit was 35.75 times higher in frozen than in fresh products. Fresh ink had significantly lower concentrations of As, Cr, Fe, and Cd, but the concentrations of Hg and Pb were not significantly different from those of other products. Frozen ink had significantly higher concentrations of Cd, Cr, and Fe, but concentrations of As were lower than those in

  17. Spin-polarized hydrogen Rydberg time-of-flight: Experimental measurement of the velocity-dependent H atom spin-polarization

    International Nuclear Information System (INIS)

    Broderick, Bernadette M.; Lee, Yumin; Doyle, Michael B.; Chernyak, Vladimir Y.; Suits, Arthur G.; Vasyutinskii, Oleg S.

    2014-01-01

    We have developed a new experimental method allowing direct detection of the velocity dependent spin-polarization of hydrogen atoms produced in photodissociation. The technique, which is a variation on the H atom Rydberg time-of-flight method, employs a double-resonance excitation scheme and experimental geometry that yields the two coherent orientation parameters as a function of recoil speed for scattering perpendicular to the laser propagation direction. The approach, apparatus, and optical layout we employ are described here in detail and demonstrated in application to HBr and DBr photolysis at 213 nm. We also discuss the theoretical foundation for the approach, as well as the resolution and sensitivity we achieve

  18. Effects of Bamboo Shoot Dietary Fiber on Mechanical Properties, Moisture Distribution, and Microstructure of Frozen Dough

    Directory of Open Access Journals (Sweden)

    Hua Zhang

    2017-01-01

    Full Text Available In this paper, the effects of Bamboo shoot dietary fiber (BSDF on the mechanical properties, moisture distribution, and microstructure of frozen dough were investigated. The state and distribution of water in frozen dough was determined by differential scanning calorimetry (DSC and low-field nuclear magnetic resonance (LNMR spectroscopy. The microstructure of frozen dough was studied. The structure of the gluten protein network found in wheat flour dough was studied by scanning electron microscopy (SEM. The result showed that the BSDF could significantly improve the viscoelasticity and extensibility of frozen dough after thawing in a dose-dependent manner. It was significantly improved with the increase in the addition amount of BSDF (P<0.05. DSC analysis showed that the freezable water content and thermal stability of frozen dough were increased after the addition of BSDF. LNMR analysis showed that the appropriate (<0.1% addition amount of BSDF could significantly (P<0.05 decline the contents of bound water. Meanwhile, the loose bound water and free water were raised significantly (P<0.05 after the addition of BSDF. Moreover, the addition of BSDF induces arrangement of starch granule and gluten network in frozen dough. BSDF can be used as a novel quality improver of frozen dough.

  19. The accuracy of frozen section analysis in ultrasound- guided core needle biopsy of breast lesions

    International Nuclear Information System (INIS)

    Brunner, Andreas H; Sagmeister, Thomas; Kremer, Jolanta; Riss, Paul; Brustmann, Hermann

    2009-01-01

    Limited data are available to evaluate the accuracy of frozen section analysis and ultrasound- guided core needle biopsy of the breast. In a retrospective analysis data of 120 consecutive handheldultrasound- guided 14- gauge automated core needle biopsies (CNB) in 109 consecutive patients with breast lesions between 2006 and 2007 were evaluated. In our outpatient clinic120 CNB were performed. In 59/120 (49.2%) cases we compared histological diagnosis on frozen sections with those on paraffin sections of CNB and finally with the result of open biopsy. Of the cases 42/59 (71.2%) were proved to be malignant and 17/59 (28.8%) to be benign in the definitive histology. 2/59 (3.3%) biopsies had a false negative frozen section result. No false positive results of the intraoperative frozen section analysis were obtained, resulting in a sensitivity, specificity and positive predicting value (PPV) and negative predicting value (NPV) of 95%, 100%, 100% and 90%, respectively. Histological and morphobiological parameters did not show up relevance for correct frozen section analysis. In cases of malignancy time between diagnosis and definitive treatment could not be reduced due to frozen section analysis. The frozen section analysis of suspect breast lesions performed by CNB displays good sensitivity/specificity characteristics. Immediate investigations of CNB is an accurate diagnostic tool and an important step in reducing psychological strain by minimizing the period of uncertainty in patients with breast tumor

  20. MICROBIOLOGICAL EVALUATION OF BOVINE FROZEN SEMEN SAMPLES IN WEST BENGAL, INDIA

    Directory of Open Access Journals (Sweden)

    Joyjit Mitra

    2016-12-01

    Full Text Available A total number of 860 French mini straws (0.25 ml of frozen semen from 215 bulls from three different farms namely frozen semen bull station (FSBS, Harighata Farm (98, FSBS, Salboni (93 and Sperm Station, Beldanga (24 were evaluated for bacterial load by standard plate count (SPC technique using soyabean casein digest agar and 1% plain agar media. Following incubation at 37°C for 72 hrs average colony forming unit (CFU was estimated and bacteria were identified. Different micro-organisms identified in frozen semen samples were Staphylococcus spp., Micrococcus spp., Escherichia coli, Pseudomonas spp., Corynebacterium spp., Proteus spp., Klebsiella spp., Bacillus spp. other than Bacillus anthracis and Streptococcus spp. Several of these bacteria have been identified in association with breeding failure in cattle and warrants precautionary and preventive measures for successful breeding program.

  1. Prediction of chemical, physical and sensory data from process parameters for frozen cod using multivariate analysis

    DEFF Research Database (Denmark)

    Bechmann, Iben Ellegaard; Jensen, H.S.; Bøknæs, Niels

    1998-01-01

    Physical, chemical and sensory quality parameters were determined for 115 cod (Gadus morhua) samples stored under varying frozen storage conditions. Five different process parameters (period of frozen storage, frozen storage. temperature, place of catch, season for catching and state of rigor) were...... varied systematically at two levels. The data obtained were evaluated using the multivariate methods, principal component analysis (PCA) and partial least squares (PLS) regression. The PCA models were used to identify which process parameters were actually most important for the quality of the frozen cod....... PLS models that were able to predict the physical, chemical and sensory quality parameters from the process parameters of the frozen raw material were generated. The prediction abilities of the PLS models were good enough to give reasonable results even when the process parameters were characterised...

  2. Frozen shoulder contracture syndrome - Aetiology, diagnosis and management.

    Science.gov (United States)

    Lewis, Jeremy

    2015-02-01

    Frozen shoulder is a poorly understood condition that typically involves substantial pain, movement restriction, and considerable morbidity. Although function improves overtime, full and pain free range, may not be restored in everyone. Frozen shoulder is also known as adhesive capsulitis, however the evidence for capsular adhesions is refuted and arguably, this term should be abandoned. The aim of this Masterclass is to synthesise evidence to provide a framework for assessment and management for Frozen Shoulder. Although used in the treatment of this condition, manipulation under anaesthetic has been associated with joint damage and may be no more effective than physiotherapy. Capsular release is another surgical procedure that is supported by expert opinion and published case series, but currently high quality research is not available. Recommendations that supervised neglect is preferable to physiotherapy have been based on a quasi-experimental study associated with a high risk of bias. Physiotherapists in the United Kingdom have developed dedicated care pathways that provide; assessment, referral for imaging, education, health screening, ultrasound guided corticosteroid and hydro-distension injections, embedded within physiotherapy rehabilitation. The entire pathway is provided by physiotherapists and evidence exists to support each stage of the pathway. Substantial on-going research is required to better understand; epidemiology, patho-aetiology, assessment, best management, health economics, patient satisfaction and if possible prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Large baby syndrome in singletons born after frozen embryo transfer (FET)

    DEFF Research Database (Denmark)

    Pinborg, Anja; Henningsen, AA; Loft, A

    2013-01-01

    Are singletons born after frozen embryo transfer (FET) at increased risk of being born large for gestational age (LGA) and if so, is this caused by intrinsic maternal factors or related to the freezing/thawing procedures?......Are singletons born after frozen embryo transfer (FET) at increased risk of being born large for gestational age (LGA) and if so, is this caused by intrinsic maternal factors or related to the freezing/thawing procedures?...

  4. 75 FR 29726 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Notice of Partial Rescission...

    Science.gov (United States)

    2010-05-27

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... antidumping duty order on certain frozen fish fillets from the Socialist Republic of Vietnam (``Vietnam''). See Notice of Antidumping Duty Order: Certain Frozen Fish Fillets From the Socialist Republic of...

  5. 76 FR 47149 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Notice of Partial Rescission...

    Science.gov (United States)

    2011-08-04

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... antidumping duty order on certain frozen fish fillets from the Socialist Republic of Vietnam (``Vietnam''). See Notice of Antidumping Duty Order: Certain Frozen Fish Fillets From the Socialist Republic of...

  6. 78 FR 55676 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Preliminary Results of the...

    Science.gov (United States)

    2013-09-11

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... order on certain frozen fish fillets (``fish fillets'') from the Socialist Republic of Vietnam... preliminary results. \\1\\ See Notice of Antidumping Duty Order: Certain Frozen Fish Fillets From the Socialist...

  7. Irradiated or aseptically prepared frozen dairy desserts: acceptability to bone marrow transplant recipients

    International Nuclear Information System (INIS)

    Dong, F.M.; Hashisaka, A.E.; Rasco, B.A.; Einstein, M.A.; Mar, D.R.; Aker, S.N.

    1992-01-01

    Sterile ice cream and frozen yogurt were offered to immunosuppressed patients recovering from bone marrow transplantation. To obtain sterile products, two of the dairy desserts (prepackaged ice cream and frozen yogurt bars) were exposed to 40 kGy of cobalt 60 irradiation. Four different flavors of ice cream were aseptically prepared under a laminar airflow hood using commercially sterilized ingredients. A commercially sterile, frozen milk-based drink on the low-microbial menu served as the control. Ratings of the seven products by 17 patients indicated that a frozen vanilla milk-based drink and aseptically prepared chocolate ice cream were highly acceptable to recovering immunosuppressed patients who have difficulty eating most foods. However, the seven desserts received higher ratings from a sensory panel of healthy individuals than from the patient panel, confirming that new foods for the low-microbial diet should be ''market-tested'' by the targeted patient population before inclusion in the menu

  8. Irradiated or aseptically prepared frozen dairy desserts: acceptability to bone marrow transplant recipients.

    Science.gov (United States)

    Dong, F M; Hashisaka, A E; Rasco, B A; Einstein, M A; Mar, D R; Aker, S N

    1992-06-01

    Sterile ice cream and frozen yogurt were offered to immunosuppressed patients recovering from bone marrow transplantation. To obtain sterile products, two of the dairy desserts (prepackaged ice cream and frozen yogurt bars) were exposed to 40 kGy of cobalt 60 irradiation. Four different flavors of ice cream were aseptically prepared under a laminar airflow hood using commercially sterilized ingredients. A commercially sterile, frozen milk-based drink on the low-microbial menu served as the control. Ratings of the seven products by 17 patients indicated that a frozen vanilla milk-based drink and aseptically prepared chocolate ice cream were highly acceptable to recovery immunosuppressed patients who have difficulty eating most foods. However, the seven desserts received higher ratings from a sensory panel of healthy individuals than from the patient panel, confirming that new foods for the low-microbial diet should be "market-tested" by the targeted patient population before inclusion in the menu.

  9. Effect of sodium tetraborate (borax) on the thermal properties of frozen aqueous sugar and polyol solutions.

    Science.gov (United States)

    Izutsu, Ken-ichi; Rimando, Annie; Aoyagi, Nobuo; Kojima, Shigeo

    2003-06-01

    The effect of sodium tetraborate (Na(2)B(4)O(7), borax) on the thermal property of frozen aqueous sugar and polyol solutions was studied through thermal analysis. Addition of borax raised the thermal transition temperature (glass transition temperature of maximally freeze-concentrated solutes; T(g)') of frozen sucrose solutions depending on the borax/sucrose concentration ratios. Changes in the T(g)' of frozen mono- and disaccharide solutions suggested various forms of complexes, including those of a borate ion and two saccharide molecules. Borax exerted the maximum effect to raise the oligosaccharide and dextran T(g)'s at borax/saccharide molar ratios of approximately 1-2 (maltose and maltooligosaccharides), 2 (dextran 1060), 5 (dextran 4900), and 10 (dextran 10200). Further addition of borax lowered T(g)'s of the saccharide solutions. Borax also raised T(g) and T(g)' temperatures of frozen aqueous glycerol solutions. The decreased solute mobility in frozen solutions by the borate-polyol complexes suggested higher collapse temperature in the freeze-drying process and improved stability of biological systems in frozen solutions.

  10. The impact of cold chain temperature abuses on the quality of frozen strawberries (Fragaria ×ananassa

    Directory of Open Access Journals (Sweden)

    Rui Cruz

    2013-04-01

    Full Text Available The quality of frozen foods can be negatively affected if improper storage and distribution temperatures are allowed. The objective of this study was to investigate the effect of freeze-thaw cycles, which may occur in the cold chain, on colour (Lab, Total Colour Differences (TCD, chroma and hue angle and vitamin C (ascorbic and dehydroascorbic acids content of frozen strawberries (Fragaria ×ananassa, Duschesne, cv. Selva. A plan of temperature abuses (TAs was established, based on a real situation, and applied to frozen strawberries during a four month frozen storage period. The results showed that the lightness (L was the only parameter that was not significantly affected by range of TAs studied. The colour showed some variation on the parameters a, b, TCD, chroma and hue angle. During TAs, ascorbic acid decreased about 75% and dehydroascorbic acid increased 73%. The non-abused strawberry samples showed better overall appearance than the abused samples. This work contributes to an understanding of the quality changes of frozen strawberries that might occur during frozen storage and cold chain distribution.

  11. Frozen shoulder or missed posterior dislocation? | Leijnen | South ...

    African Journals Online (AJOL)

    South African Journal of Sports Medicine ... has similarities with an idiopathic frozen shoulder masking proper diagnosis at the time of injury. ... shoulder pain which demonstrates the importance of correct initial diagnosis and management.

  12. Effect of freezing temperature on the color of frozen salmon.

    Science.gov (United States)

    Ottestad, Silje; Enersen, Grethe; Wold, Jens Petter

    2011-09-01

    New freezing methods developed with the purpose of improved product quality after thawing can sometimes be difficult to get accepted in the market. The reason for this is the formation of ice crystals that can give the product a temporary color loss and make it less appealing. We have here used microscopy to study ice crystal size as a function of freezing temperature by investigating the voids in the cell tissue left by the ice crystals. We have also investigated how freezing temperature affects the color and the visible absorption spectra of frozen salmon. Freezing temperatures previously determined to be the best for quality after thawing (-40 to -60 °C) were found to cause a substantial loss in perceived color intensity during frozen state. This illustrated the conflict between optimal freezing temperatures with respect to quality after thawing against visual appearance during frozen state. Low freezing temperatures gave many small ice crystals, increased light scattering and an increased absorption level for all wavelengths in the visible region. Increased astaxanthin concentration on the other hand would give higher absorption at 490 nm. The results showed a clear potential of using visible interactance spectroscopy to differentiate between poor product coloration due to lack of pigmentation and temporary color loss due to light scattering by ice crystal. This type of measurements could be a useful tool in the development of new freezing methods and to monitor ice crystal growth during frozen storage. It could also potentially be used by the industry to prove good product quality. In this article we have shown that freezing food products at intermediate to low temperatures (-40 to -80 °C) can result in paler color during frozen state, which could affect consumer acceptance. We have also presented a spectroscopic method that can separate between poor product color and temporary color loss due to freezing. © 2011 Institute of Food Technologists®

  13. 40 CFR 405.80 - Applicability; description of the ice cream, frozen desserts, novelties and other dairy desserts...

    Science.gov (United States)

    2010-07-01

    ... cream, frozen desserts, novelties and other dairy desserts subcategory. 405.80 Section 405.80 Protection... PRODUCTS PROCESSING POINT SOURCE CATEGORY Ice Cream, Frozen Desserts, Novelties and Other Dairy Desserts Subcategory § 405.80 Applicability; description of the ice cream, frozen desserts, novelties and other dairy...

  14. 75 FR 12726 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Final Results of the...

    Science.gov (United States)

    2010-03-17

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... two new shipper reviews of the antidumping duty order on certain frozen fish fillets from the... of price or production. See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam...

  15. 76 FR 61088 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Initiation of New Shipper...

    Science.gov (United States)

    2011-10-03

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... antidumping duty order on certain frozen fish fillets from the Socialist Republic of Vietnam, received between... on certain frozen fish fillets from the Socialist Republic of Vietnam was published in the Federal...

  16. Influence of pH on the physicochemical and sensorial characteristics of strawberry frozen yogurtInfluência do pH nas características físico-químicas e sensoriais de frozen yogurt de morango

    Directory of Open Access Journals (Sweden)

    Jaime Vilela de Resende

    2012-05-01

    Full Text Available Frozen yogurt is a frozen fermented dessert which presents structural characteristics similar to ice cream and nutritional and sensorial properties which resemble to yogurt. The acidification of ice cream mix by means of lactic bacteria can influence the properties of frozen yogurt. For that reason, the present work aimed to evaluate the influence of pH on the physicochemical and sensorial characteristics of strawberry frozen yogurt. The formulation consisted of 6 % of milk fat, 10 % of milk solids-not-fat, 11 % of sucrose, 3 % of corn syrup, 0.3 % of emulsifiers and 0.5 % of stabilizers. The frozen yogurt mixes were made with different fermentation endpoints, pH values of 4.5, 5.0 and 5.5. The strawberry fruit mixture was added to the fermented frozen yogurt mix at a level of 4 % (w/w. According to the results, the pH of the frozen yogurt mix did not influence the concentrations of protein, fat and ash whereas the contents of acidity, reducing, non-reducing and total sugars underwent influence of pH due to fermentation. The acceptability of frozen yogurt in relation to the attributes flavor, texture, overall acceptance and ideal acidity was evaluated. It was found that pH influenced the acceptance of frozen yogurt; the treatments with final pH of 5.0 and 5.5 presented higher acceptability for all the treatments evaluated and acidity close to the ideal. By means of the principal component analysis, it was found that the physicochemical characteristics acidity content and sugar concentration (reducing, non-reducing and total had effect on the acceptance of the product. In conclusion, the strawberry frozen yogurts with pH 5.0 and 5.5 demonstrated good sensorial acceptance and thus, presented potential of being better explored by the ice cream industries. O frozen yogurt é uma sobremesa fermentada congelada que apresenta características estruturais semelhantes ao sorvete e propriedades nutricionais e sensoriais que se assemelham ao iogurte. A

  17. Explosion Source Characteristics in Frozen and Unfrozen Rock

    National Research Council Canada - National Science Library

    Bonner, Jessie L; Leidig, Mark R; Murphy, Katherine; Dougherty, Sara L; Martin, Randolph J

    2008-01-01

    .... Central Alaska has abrupt lateral boundaries in discontinuous permafrost, and we detonated 3 shots in frozen, saturated rock and 3 shots nearby in unfrozen, dry rock ranging in size from 200 to 350 Ibs...

  18. Psychrophiles and astrobiology: microbial life of frozen worlds

    Science.gov (United States)

    Pikuta, Elena V.; Hoover, Richard B.

    2003-01-01

    Most bodies of our Solar System are "Frozen Worlds" where the prevailing surface temperature remains at or below freezing. On Earth there are vast permanently frozen regions of permafrost, polar ice sheets, and glaciers and the deep oceans and deep-sea marine sediments have remained at 2 - 4°C for eons. Psychrophilic and psychrotrophic microbiota that inhabit these regimes provide analogs for microbial life that might inhabit ice sheets and permafrost of Mars, comets, or the ice/water interfaces or sediments deep beneath the icy crusts of Europa, Callisto, or Ganymede. Cryopreserved micro-organisms can remain viable (in a deep anabiotic state) for millions of years frozen in permafrost and ice. Psychrophilic and psychrotrophic (cold-loving) microbes can carry out metabolic processes in water films and brine, acidic, or alkaline chanels in permafrost or ice at temperatures far below 0°C. These microbes of the cryosphere help define the thermal and temporal limits of life on Earth and may provide clues to where and how to search for evidence of life elsewhere in the Cosmos. Astrobiologists at the NASA Marshall Space Flight Center have collected microbial extremophiles from the Pleistocene ice wedges and frozen thermokarst ponds from the Fox Permafrost Tunnel of Alaska. Microbes have also been isolated from samples of Magellanic Penguin guano from Patagonia; deep-sea marine muds near hydrothermal vents; snow and permafrost from Siberia, and deep ice cores, ice-bubble and cryoconite rocks of the Central Antarctic Ice Sheet. These samples have yielded microbial extremophiles representing a wide variety of anaerobic bacteria and archaea. These microbes have been isolated, cultured, characterized and analyzed by phylogenetic and genomic methods. Images were obtained by Phase Contrast, Environmental, Field Emission Scanning and Transmission Electron Microscopes to study the ultra-microstructure and elemental distribution in the composition of these micro-organisms. We

  19. SMOKED AND FROZEN FISH CONSUMPTION AND MARKETING ...

    African Journals Online (AJOL)

    Apusigah

    There is also a high demand for fish because it is an important source of cheap first class protein ... While hotel kitchens deep fry, grill and bake for ... fish and the price per kilogram of both smoked and frozen fish with a view to improving the.

  20. SUPPLY CHAIN MANAGEMENT OF IMPORTED FROZEN BEEF: AN ALTERNATIVE TO INTEGRATE WITH LOCAL BEEF SUPPLY CHAIN MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Sani R.

    2017-12-01

    Full Text Available The purpose of this study is to describe the supply chain management of imported frozen beef from Australia to Indonesia; to analyze where the strengths, weaknesses, opportunities, and threats for the frozen meat distributor, and what strategy should be chosen; and to analyze alternatives of cooperation between imported frozen beef distribution with local beef distribution chain. The research approach is qualitative, and the research strategy is a case study. This research was conducted in Jakarta, data collecting technique by interview method and literature study. Data analysis techniques use supply chain management (SCM and strengths, weaknesses, opportunities, and threats (SWOT analysis. The results show that the distribution chain management of imported frozen beef needs to tripartite cooperation with government and local beef distributors to conduct joint marketing of imported frozen beef and cooler procurement to the point of retailers in traditional markets; expanding the market share of imported frozen beef to industrial segments (hotels, restaurant, catering company; and meat processing factories; and cooperate with imported beef suppliers to overcome the problem of taste flavor and lack of weight of imported frozen meat, and clarify halal certification.

  1. 78 FR 15686 - Certain Frozen Warmwater Shrimp From Thailand: Preliminary Results of Antidumping Duty...

    Science.gov (United States)

    2013-03-12

    ... Records Unit (CRU), room 7046 of the main Department of Commerce building. In addition, a complete version... Frozen Foods 0.51 Co., Ltd Lee Heng Seafood Co., Ltd 0.51 Leo Transports * Li-Thai Frozen Foods Co., Ltd...

  2. Frozen Microemulsions for MAPLE Immobilization of Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2017-12-01

    Full Text Available Candida rugosa lipase (CRL was deposited by matrix assisted pulsed laser evaporation (MAPLE in order to immobilize the enzyme with a preserved native conformation, which ensures its catalytic functionality. For this purpose, the composition of the MAPLE target was optimized by adding the oil phase pentane to a water solution of the amino acid 3-(3,4-dihydroxyphenyl-2-methyl-l-alanine (m-DOPA, giving a target formed by a frozen water-lipase-pentane microemulsion. Fourier transform infrared (FTIR spectroscopy and atomic force microscopy (AFM were used to investigate the structure of MAPLE deposited lipase films. FTIR deconvolution of amide I band indicated a reduction of unfolding and aggregation, i.e., a better preserved lipase secondary structure in the sample deposited from the frozen microemulsion target. AFM images highlighted the absence of big aggregates on the surface of the sample. The functionality of the immobilized enzyme to promote transesterification was determined by thin layer chromatography, resulting in a modified specificity.

  3. 78 FR 48415 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Amended Final Results of...

    Science.gov (United States)

    2013-08-08

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... review of the antidumping duty order on certain frozen fish fillets (``fish fillets'') from the Socialist... August 1, 2011, through January 31, 2012. \\1\\ See Certain Frozen Fish Fillets from the Socialist Republic...

  4. 76 FR 70111 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Extension of Deadline for...

    Science.gov (United States)

    2011-11-10

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... antidumping duty order on certain frozen fish fillets from the Socialist Republic of Vietnam (``Vietnam'').\\1... 4, 2011.\\3\\ \\1\\ See Notice of Antidumping Duty Order: Certain Frozen Fish Fillets from the Socialist...

  5. 78 FR 29323 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Amended Final Results of...

    Science.gov (United States)

    2013-05-20

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... administrative review and aligned new shipper reviews on certain frozen fish fillets (``fish fillets'') from the... (``POR'') is August 1, 2010, through July 31, 2011. \\1\\ See Certain Frozen Fish Fillets from the...

  6. Efficient recovery of fluoroquinolone-susceptible and fluoroquinolone-resistant Escherichia coli strains from frozen samples.

    Science.gov (United States)

    Lautenbach, Ebbing; Santana, Evelyn; Lee, Abby; Tolomeo, Pam; Black, Nicole; Babson, Andrew; Perencevich, Eli N; Harris, Anthony D; Smith, Catherine A; Maslow, Joel

    2008-04-01

    We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only in low numbers in the initial sample. These findings emphasize the utility of frozen surveillance samples.

  7. Coulomb states in atoms and solids

    International Nuclear Information System (INIS)

    Ortalano, D.M.

    1988-05-01

    In this dissertation, an empirical quantum defect approach to describe the valence excitons of the rare gas solids is developed. These Coulomb states are of s-symmetry and form a hydrogen-like series which converges to the bottom of the lowest conduction band. A non-zero quantum defect is found for all of the excitons of neon, argon and xenon. For these systems, then, there exists, in addition to the screened Coulombic component, a non-Coulombic component to the total exciton binding energy. The Wannier formalism is, therefore, inappropriate for the excitons of Ne, Ar and Xe. From the sign of the quantum defect, the non-Coulombic potential is repulsive for Ne and Ar, attractive for Xe, and nearly zero for Kr. This is opposite to that for the Rydberg states of the corresponding rare gas atoms, where the non-Coulombic potential between the electron and the cation is attractive for all of the atoms. The excitons then, are not simply perturbed Rydberg states of the corresponding rare gas atoms (i.e., the excitons do not possess atomic parentage). Interatomic term value/band gap energy correlations and reduced term value/reduced band gap correlations were performed. These correlations were exploited to provide further evidence against both the Wannier formalism and the atomic parentage view point. From these correlations, it was also discovered that the non-Coulombic potential varies smoothly across the valence isoelectronic series of solids, and that it becomes more attractive (or less repulsive) in going from neon to xenon. In order to address the atomic parentage controversy, it was necessary to compare the excitons to the low-n Rydberg states of the rare gas atoms. A review of the quantum defect description of the atomic Rydberg states is, therefore, presented. Also, Rydberg term value/ionization energy correlations are discussed and compared with the analogous exciton correlations. 7 refs., 10 figs., 5 tabs

  8. Evaluation of the ovarian reserve in women transplanted with frozen and thawed ovarian cortical tissue

    DEFF Research Database (Denmark)

    Greve, Tine; Schmidt, Kirsten Tryde; Kristensen, Stine Gry

    2012-01-01

    To investigate ovarian reserve and ovarian function in women transplanted with frozen/thawed ovarian tissue.......To investigate ovarian reserve and ovarian function in women transplanted with frozen/thawed ovarian tissue....

  9. Interaction of Rydberg atoms with two contrapropagating ultrashort laser pulses

    International Nuclear Information System (INIS)

    Lugovskoy, A. V.; Bray, I.

    2006-01-01

    In this paper we investigate how Rydberg atoms respond to perturbation by two contrapropagating ultrashort laser pulses. We consider the case where the durations of both pulses τ 1 and τ 2 are shorter than the inverse of the initial-state energy ε i -1 . When acting alone such a pulse passes through the atom without noticeable alteration in the atomic state. The situation is different if two such pulses interfere in the region of atom localization. In this case the atomic response is significantly enhanced. This is due to the nonzero momentum transferred to the electron by the interplay of the electric field of one pulse and the magnetic field of the other. The sudden perturbation approximation is used to evaluate the transition probabilities. They are shown to depend on the atom position with respect to the pulse interference region. This dependence is determined by the relationship between the atomic diameter d i and the interference-region size l=c(τ 1 +τ 2 ) (c is the speed of light). If d i i >>l the transition probabilities are sensitive to the electron density distribution along the propagation direction. The probabilities of the initial-state destruction and atom ionization drop as l/d i irrespective of the characteristics of the pulses

  10. Frozen blood products: clinically effective and potentially ideal for remote Australia.

    Science.gov (United States)

    Holley, A; Marks, D C; Johnson, L; Reade, M C; Badloe, J F; Noorman, F

    2013-01-01

    The development of effective cryopreservation techniques for both red blood cells and platelets, which maintain ex vivo biological activity, in combination with frozen plasma, provides for a unique blood banking strategy. This technology greatly enhances the storage life of these products. The rationale and potential advantages of using cryopreservation techniques for the provision of blood products to remote and military environments have been effectively demonstrated in several conflicts over the last decade. Current haemostatic resuscitation doctrine for the exsanguinating patient supports the use of red blood cells, platelets and frozen plasma early in the resuscitation. We believe an integrated fresh-frozen blood bank inventory could facilitate provision of blood products, not only in the military setting but also in regional Australia, by overcoming many logistic and geographical challenges. The processes involved in production and point of care thawing are sufficiently well developed and achievable to make this technology a viable option. The potential limitations of cryopreservation and subsequent product thawing need to be considered if such a strategy is to be developed. A substantial body of international experience using cryopreserved products in remote settings has already been accrued. This experience provides a template for the possible creation of an Australian integrated fresh-frozen blood bank inventory that could conceivably enhance the care of patients in both regional Australia and in the military setting.

  11. Characterization of a frozen shoulder model using immobilization in rats.

    Science.gov (United States)

    Kim, Du Hwan; Lee, Kil-Ho; Lho, Yun-Mee; Ha, Eunyoung; Hwang, Ilseon; Song, Kwang-Soon; Cho, Chul-Hyun

    2016-12-08

    The objective of this study was to investigate serial changes for histology of joint capsule and range of motion of the glenohumeral joint after immobilization in rats. We hypothesized that a rat shoulder contracture model using immobilization would be capable of producing effects on the glenohumeral joint similar to those seen in patients with frozen shoulder. Sixty-four Sprague-Dawley rats were randomly divided into one control group (n = 8) and seven immobilization groups (n = 8 per group) that were immobilized with molding plaster for 3 days, or for 1, 2, 3, 4, 5, or 6 weeks. At each time point, eight rats were euthanized for histologic evaluation of the axillary recess and for measurement of the abduction angle. Infiltration of inflammatory cells was found in the synovial tissue until 2 weeks after immobilization. However, inflammatory cells were diminished and fibrosis was dominantly observed in the synovium and subsynovial tissue 3 weeks after immobilization. From 1 week after immobilization, the abduction angle of all immobilization groups at each time point was significantly lower than that of the control group. Our study demonstrated that a rat frozen shoulder model using immobilization generates the pathophysiologic process of inflammation leading to fibrosis on the glenohumeral joint similar to that seen in patients with frozen shoulder. This model was attained within 3 weeks after immobilization. It may serve as a useful tool to investigate pathogenesis at the molecular level and identify potential target genes that are involved in the development of frozen shoulder.

  12. Development of Alaskan gas hydrate resources: Annual report, October 1986--September 1987

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, G.D.; Kamath, V.A.; Godbole, S.P.; Patil, S.L.; Paranjpe, S.G.; Mutalik, P.N.; Nadem, N.

    1987-10-01

    Solid ice-like mixtures of natural gas and water in the form of natural gas hydrated have been found immobilized in the rocks beneath the permafrost in Arctic basins and in muds under the deep water along the American continental margins, in the North Sea and several other locations around the world. It is estimated that the arctic areas of the United States may contain as much as 500 trillion SCF of natural gas in the form of gas hydrates (Lewin and Associates, 1983). While the US Arctic gas hydrate resources may have enormous potential and represent long term future source of natural gas, the recovery of this resource from reservoir frozen with gas hydrates has not been commercialized yet. Continuing study and research is essential to develop technologies which will enable a detailed characterization and assessment of this alternative natural gas resource, so that development of cost effective extraction technology.

  13. 9 CFR 327.21 - Inspection procedures for chilled fresh and frozen boneless manufacturing meat.

    Science.gov (United States)

    2010-01-01

    ... fresh and frozen boneless manufacturing meat. 327.21 Section 327.21 Animals and Animal Products FOOD... MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION IMPORTED PRODUCTS § 327.21 Inspection procedures for chilled fresh and frozen boneless manufacturing meat. (a) Definitions...

  14. High-resolution measurements and multichannel quantum defect analysis of spectral line shapes of autoionizing Rydberg series

    International Nuclear Information System (INIS)

    Ueda, Kiyoshi

    1997-01-01

    Spectral line shapes for autoionizing Rydberg series are briefly reviewed within the framework of multichannel quantum defect theory (MQDT). Recent high-resolution measurements and MQDT analysis for the spectra line shapes are reviewed for the mp 5 ( 2 P 1/2 )ns ' and nd ' J=1 odd spectra of the Ar, Kr, and Xe atoms (m=3,4,5 for Ar, Kr, and Xe) and the 3p 5 ( 2 P 1/2 )nd ' J=2 and 3 odd spectra of Ar*3p 5 4p excited atoms. Some results are also discussed for the Ca 4p( 2 P 1/2,3/2 )ns and nd J=1 odd spectrum and the Ba 5d( 2 P 5/2 )nd J=1 odd spectrum

  15. KAJIAN PENGGUNAAN WHEY BUBUK SEBAGAI PENGGANTI SUSU SKIM BUBUK DALAM PENGOLAHAN SOFT FROZEN ES KRIM

    Directory of Open Access Journals (Sweden)

    M. E. Sawitri

    2010-04-01

    Full Text Available The objectives of this research were to determine effect of substitution level of skim milk powder with whey powder on the quality of soft frozen ice cream and as an information for practician and industry related the research product. The materials of the research were soft frozen ice cream, the treatment were substitution levels of skim milk powder with whey powder (w/w :W0 (0%, W1 (25%, W2 (50%, W3 (75% and W4 (100% from solid non fat. The research method was an experiment using Randomized Block Design, with three replication. The variables measured were the overrun, melting rate, and organoleptic quality of soft frozen ice cream. Data were analyzed by analysis of variance and followed by Duncan’s Multiple Ranger Test. The result of the research showed that substitution level of skim milk powder with whey powder gave a highly significant effect (P<0,01 on overrun, melting rate and organoleptic quality of soft frozen ice cream. The substitution of skim milk powder with whey powder 75% (w/w gave the best quality of soft frozen ice cream according to the SNI which had 10% fat, 13% of sugar and 36% of solid. (JIIPB 2010 Vol 20 No 1: 31-37. Keywords : whey powder, skim milk powder, soft frozen ice cream

  16. Vapor cell geometry effect on Rydberg atom-based microwave electric field measurement

    Science.gov (United States)

    Zhang, Linjie; Liu, Jiasheng; Jia, Yue; Zhang, Hao; Song, Zhenfei; Jia, Suotang

    2018-03-01

    The geometry effect of a vapor cell on the metrology of a microwave electric field is investigated. Based on the splitting of the electromagnetically induced transparency spectra of cesium Rydberg atoms in a vapor cell, high-resolution spatial distribution of the microwave electric field strength is achieved for both a cubic cell and a cylinder cell. The spatial distribution of the microwave field strength in two dimensions is measured with sub-wavelength resolution. The experimental results show that the shape of a vapor cell has a significant influence on the abnormal spatial distribution because of the Fabry–Pérot effect inside a vapor cell. A theoretical simulation is obtained for different vapor cell wall thicknesses and shows that a restricted wall thickness results in a measurement fluctuation smaller than 3% at the center of the vapor cell. Project supported by the National Key Research and Development Program of China (Grant Nos. 2017YFA03044200 and 2016YFF0200104), the National Natural Science Foundation of China (Grant Nos. 91536110, 61505099, and 61378013), and the Fund for Shanxi “331 Project” Key Subjects Construction, China.

  17. A retrospective study of artificial insemination of 251 mares using chilled and fixed time frozen-thawed semen.

    Science.gov (United States)

    Crowe, C A M; Ravenhill, P J; Hepburn, R J; Shepherd, C H

    2008-09-01

    Historically, artificial insemination (AI) using frozen semen has been perceived to have poorer success rates and be more labour intensive than using chilled semen. A retrospective study was therefore conducted to compare the conception rate achieved by AI between chilled and frozen semen, using fixed time insemination protocols over 2 breeding seasons. Artificial insemination using chilled semen produces a higher conception rate than that achieved with frozen semen. Mares (n = 251) were inseminated with either chilled (n = 112) or frozen (n = 139) semen in the 2006 and 2007 northern hemisphere breeding season. Per rectum ultrasonography of the mare's reproductive tract determined the timing of insemination, and deslorelin acetate was used to induce ovulation. Chilled semen insemination was performed using a single preovulatory dose delivered into the uterine body. Frozen semen was administered as 2 doses (pre- and post ovulation) using a deep uterine insemination technique. Pregnancy was detected ultrasonographically at 15 days post insemination. Conception rates were compared using a Chi-squared test. Insemination with frozen semen produced a significantly (P = 0.022) higher seasonal conception rate (82.0%) than that achieved with chilled semen (69.6%). Insemination with frozen semen can achieve conception rates equal to those with chilled semen, enabling the mare owner a greater selection of stallions.

  18. Ion induced polymerization in benzene frozen films

    Energy Technology Data Exchange (ETDEWEB)

    Calcagno, G [Catania Univ. (Italy). Ist. di Fisica; Strazzulla, G [Catania Univ. (Italy). Osservatorio Astrofisico; Fichera, M; Foti, G [Catania Univ. (Italy). Ist. di Radiologia

    1983-07-01

    The cross section of the polymerization process induced by energetic protons colliding with frozen benzene layers has been measured. The results have been described by a simple theory and they show that the process is a volume one occurring along the ion track and interesting all of the crossed layers.

  19. Comparison of enterotomy leak pressure among fresh, cooled, and frozen-thawed porcine jejunal segments.

    Science.gov (United States)

    Aeschlimann, Kimberly A; Mann, F A; Middleton, John R; Belter, Rebecca C

    2018-05-01

    OBJECTIVE To determine whether stored (cooled or frozen-thawed) jejunal segments can be used to obtain dependable leak pressure data after enterotomy closure. SAMPLE 36 jejunal segments from 3 juvenile pigs. PROCEDURES Jejunal segments were harvested from euthanized pigs and assigned to 1 of 3 treatment groups (n = 12 segments/group) as follows: fresh (used within 4 hours after collection), cooled (stored overnight at 5°C before use), and frozen-thawed (frozen at -12°C for 8 days and thawed at room temperature [23°C] for 1 hour before use). Jejunal segments were suspended and 2-cm enterotomy incisions were made on the antimesenteric border. Enterotomies were closed with a simple continuous suture pattern. Lactated Ringer solution was infused into each segment until failure at the suture line was detected. Leak pressure was measured by use of a digital transducer. RESULTS Mean ± SD leak pressure for fresh, cooled, and frozen-thawed segments was 68.3 ± 23.7 mm Hg, 55.3 ± 28.1 mm Hg, and 14.4 ± 14.8 mm Hg, respectively. Overall, there were no significant differences in mean leak pressure among pigs, but a significant difference in mean leak pressure was detected among treatment groups. Mean leak pressure was significantly lower for frozen-thawed segments than for fresh or cooled segments, but mean leak pressure did not differ significantly between fresh and cooled segments. CONCLUSIONS AND CLINICAL RELEVANCE Fresh porcine jejunal segments or segments cooled overnight may be used for determining intestinal leak pressure, but frozen-thawed segments should not be used.

  20. 75 FR 30374 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-06-01

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets.... See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Preliminary Results of New.... See Memorandum to the File, from Javier Barrientos, Senior Case Analyst, Certain Frozen Fish Fillets...