Sample records for emulsion experiment nucleus-nucleus

  1. Particle correlations in JACEE (Japanese-American Cooperative Emulsion Experiment) nucleus-nucleus collisions

    SciTech Connect

    Not Available

    1990-01-01

    Correlations in the production of charged particles and photons can be examined in detail in the central and forward rapidity range using high multiplicity ({ge}100 charged tracks) events from JACEE emulsion chambers. Results are presented on several forms of correlations studies. 9 refs., 2 figs.

  2. Analysis of relativistic nucleus-nucleus interactions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

    The development of a computer-assisted method is reported for the determination of the angular distribution data for secondary particles produced in relativistic nucleus-nucleus collisions in emulsions. The method is applied to emulsion detectors that were placed in a constant, uniform magnetic field and exposed to beams of 60 and 200 GeV/nucleon O-16 ions at the Super Proton Synchrotron (SPS) of the European Center for Nuclear Research (CERN). Linear regression analysis is used to determine the azimuthal and polar emission angles from measured track coordinate data. The software, written in BASIC, is designed to be machine independent, and adaptable to an automated system for acquiring the track coordinates. The fitting algorithm is deterministic, and takes into account the experimental uncertainty in the measured points. Further, a procedure for using the track data to estimate the linear momenta of the charged particles observed in the detectors is included.

  3. Results on ultra-relativistic nucleus-nucleus interactions from balloon-borne emulsion chambers

    NASA Technical Reports Server (NTRS)

    Burnett, T. H.; Dake, S.; Derrickson, J. H.; Fountain, W.; Meegan, C. A.; Takahashi, Y.; Watts, J. W.; Fuki, M.; Gregory, J. C.; Hayashi, T.

    1985-01-01

    The results of balloon-borne emulsion-chamber measurements on high-energy cosmic-ray nuclei (Burnett et al., 1983) are summarized in tables and graphs and briefly characterized. Special consideration is given to seven nucleus-nucleus interaction events at energy in excess of 1 TeV/A with multiplicity greater than 400, and to Fe interactions (53 with CHO, 10 with emulsion, and 14 with Pb) at 20-60 GeV/A.

  4. Fluctuation analysis of relativistic nucleus-nucleus collisions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1988-01-01

    An analytical technique was developed for identifying enhanced fluctuations in the angular distributions of secondary particles produced from relativistic nucleus-nucleus collisions. The method is applied under the assumption that the masses of the produced particles are small compared to their linear momenta. The importance of particles rests in the fact that enhanced fluctuations in the rapidity distributions is considered to be an experimental signal for the creation of the quark-gluon-plasma (QGP), a state of nuclear matter predicted from the quantum chromodynamics theory (QCD). In the approach, Monte Carlo simulations are employed that make use of a portable random member generator that allow the calculations to be performed on a desk-top computer. The method is illustrated with data taken from high altitude emulsion exposures and is immediately applicable to similar data from accelerator-based emulsion exposures.

  5. Nucleus-nucleus potentials

    SciTech Connect

    Satchler, G.R.

    1983-01-01

    The significance of a nucleus-nucleus potential is discussed. Information about such potentials obtained from scattering experiments is reviewed, including recent examples of so-called rainbow scattering that probe the potential at smaller distances. The evidence for interactions involving the nuclear spins is summarized, and their possible origin in couplings to non-elastic channels. Various models of the potentials are discussed.

  6. Large area emulsion chamber experiments for the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Parnell, T. A.

    1985-01-01

    Emulsion-chamber experiments employing nuclear-track emulsions, etchable plastic detectors, metal plates, and X-ray films continue to demonstrate high productivity and potential in the study of cosmic-ray primaries and their interactions. Emulsions, with unsurpassed track-recording capability, provide an appropriate medium for the study of nucleus-nucleus interactions at high energy, which will likely produce observations of a phase change in nuclear matter. The many advantages of emulsion chambers (excellent multitrack recording capability, large geometry factor, low apparatus cost, simplicity of design and construction) are complemented by the major advantages of the Space Shuttle as an experiment carrier. A Shuttle experiment which could make a significant advance in both cosmic-ray primary and nucleus-nucleus interaction studies is described. Such an experiment would serve as a guide for use of emulsions during the Space Station era. Some practical factors that must be considered in planning a Shuttle exposure of emulsion chambers are discussed.

  7. Nuclear emulsions in the OPERA experiment

    E-print Network

    Donato Di Ferdinando; for the OPERA Collaboration

    2008-12-02

    The use of emulsions as particles detector has a long and successful life. The recent development of fast automatized analysis systems has allowed the use of huge amount of emulsions films with no precedence in the history of particle physics. The OPERA experiment, running in the underground Laboratori Nazionali del Gran Sasso (LNGS), for the confirmation of the neutrino oscillation in the $\

  8. Subthreshold ? meson production in nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Piasecki, K.

    2014-04-01

    Part of emission of the negatively charged kaons from the nucleus-nucleus collisions appears to originate from decays of ?(1020) mesons into the K+K- channel. We report on the measurement of the emission yield of ? mesons in the collisions of Ni+Ni at the beam kinetic energy of 1.91A GeV. The experiment was done with the FOPI spectrometer at the SIS 18 accelerator at GSI, Darmstadt. The total yield of ? was found to be (4.5 ± 0.7-1.2+1.8) · 10-4 per triggered event. Ratio of ?/K- emission yields was estimated at 0.42±0.13-0.11+0.17, meaning that about 20% of negatively charged kaons emitted from the collision originate from decays of ? mesons. The results are in agreement with similar HADES results done for the collisions of Ar+KCl.

  9. Transverse Energy in nucleus-nucleus collisions: A review

    SciTech Connect

    Tincknell, M.

    1988-11-15

    The status of Transverse Energy (E/sub T/) in relativistic nucleus-nucleus collisions at the Brookhaven AGS and the CERN SPS is reviewed. The definition of E/sub T/ and its physical significance are discussed. The basic techniques and limitations of the experimental measurements are presented. The acceptances of the major experiments to be discussed are shown, along with remarks about their idiosyncrasies. The data demonstrate that the nuclear geometry of colliding spheres primarily determines the shapes of the observed spectra. Careful account of the acceptances is crucial to comparing and interpreting results. It is concluded that nuclear stopping power is high, and that the amount of energy deposited into the interaction volume is increasing with beam energy even at SPS energies. The energy densities believed to be obtained at the SPS are close to the critical values predicted for the onset of a quark-gluon plasma. 25 refs., 8 figs.

  10. Convergence of the nucleus-nucleus Glauber multiple scattering series

    SciTech Connect

    Usmani, A.A.; Ahmad, I. (Department of Physics, Aligarh Muslim University, Aligarh 202 002, Uttar Pradesh, India (IN))

    1991-05-01

    The Glauber {ital S}-matrix operator for nucleus-nucleus scattering is expressed as a finite series of matrix elements involving Bell's polynomials. Analyzing {alpha}{sup 4}He elastic-scattering data at the incident momentum of 4.32 GeV/{ital c}, we infer that our expansion is appreciably converging. Further, by applying closure over target and projectile states and neglecting a certain class of terms involving intermediate excitations, we arrive at a recurrence relation for nucleus-nucleus multiple scattering series terms, which invites further study as it seems to provide a simple method for calculating the nucleus-nucleus elastic-scattering cross section.

  11. Emulsion Chamber Technology Experiment (ECT)

    NASA Technical Reports Server (NTRS)

    Gregory, John C.; Takahashi, Yoshiyuki

    1996-01-01

    The experimental objective of Emulsion Chamber Technology (ECT) was to develop space-borne emulsion chamber technology so that cosmic rays and nuclear interactions may subsequently be studied at extremely high energies with long exposures in space. A small emulsion chamber was built and flown on flight STS-62 of the Columbia in March 1994. Analysis of the several hundred layers of radiation-sensitive material has shown excellent post-flight condition and suitability for cosmic ray physics analysis at much longer exposures. Temperature control of the stack was 20 +/-1 C throughout the active control period and no significant deviations of temperature or pressure in the chamber were observed over the entire mission operations period. The unfortunate flight attitude of the orbiter (almost 90% Earth viewing) prevented any significant number of heavy particles (Z greater than or equal to 10) reaching the stack and the inverted flow of shower particles in the calorimeter has not allowed evaluation of absolute primary cosmic ray-detection efficiency nor of the practical time limits of useful exposure of these calorimeters in space to the level of detail originally planned. Nevertheless, analysis of the observed backgrounds and quality of the processed photographic and plastic materials after the flight show that productive exposures of emulsion chambers are feasible in low orbit for periods of up to one year or longer. The engineering approaches taken in the ECT program were proven effective and no major environmental obstacles to prolonged flight are evident.

  12. Experiment S009: Nuclear Emulsion

    NASA Technical Reports Server (NTRS)

    Odell, F. W.; Shapiro, M. M.; Silberberg, R.; Stiller, B.; Tsao, C. H.; Durgaprasad, N.; Fichtel, C. E.; Guss, D. E.; Reames, D. V.

    1971-01-01

    The first exposure on a spacecraft of a nuclear emulsion apparatus designed to collect 1000 high quality tracks of heavy nuclei under a negligible thickness of matter (0.07 g/sq cm) is described. The cosmic ray detector consisted of a stack of nuclear emulsions that were designed to register at least 400 heavy nuclei tracks for each 10 hours of useful exposure. The spacecraft had to be oriented in a heads-up attitude during the 10-hour period to eliminate atmospheric albedo particles. The results are as follows: (1) a definite odd-even effect, with low abundances for elements of atomic number 7, 9, and 11; (2) a ratio O/C approximately 0.9; (3) Ne/C, Mg/C, and Si/C ratios between 0.2 and 0.3; (4) an abundance gap in the region 15 less than or equal to Z less than or equal to 19; and (5) a ratio (20 less than or equal to Z less than or equal to 28)/C 0.2, with a large concentration at Z = 26. These results are indicative that successful exposures of nuclear emulsions were obtained on the Gemini 11 mission.

  13. Nuclear Emulsion - Skylab Experiment S009

    NASA Technical Reports Server (NTRS)

    1970-01-01

    This photograph shows Skylab's Nuclear Emulsion experiment, a Skylab science facility that was mounted inside the Multiple Docking Adapter used to record the relative abundance of primary, high-energy heavy nuclei outside the Earth's atmosphere. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

  14. Strangeness production in nucleus-nucleus collisions: An experimental review

    SciTech Connect

    Odyniec, G.

    1990-12-01

    In experiments with oxygen (60 and 200 GeV/N) and sulphur (200 GeV/N) ions at CERNSPS, large energy densities of the order of 2--3 GeV/fm{sub 3} have been observed, which according to QCD calculations, satisfy necessary conditions for the formation of a quark gluon plasma (QGP) phase. Under such conditions, colour would no longer be confined to hadronic dimensions, and quarks and gluons will propagate freely throughout an extended volume. Somehow lower energy densities, of the order of 0.7--1 GeV/fm{sub 3}, were observed in AGS experiments with 15 GeV/N silicon beams and heavy targets. These energy densities might be adequate for investigations of the pre-equilibrium stage, during which the momentum space distribution has been degradated from its initial value but is not yet thermal. First experimental results, available now, show promise of seeing signs of a new phase of matter. In this review the current status of the selective experimental results on strange-particle production, which are relevant to equilibration and QGP formation in nucleus-nucleus collisions, is presented.

  15. Nucleus-nucleus interactions between 20 and 65 GeV per nucleon

    SciTech Connect

    Burnett, T.H.; Dake, S.; Derrickson, J.H.; Fountain, W.F.; Fuki, M.; Gregory, J.C.; Hayashi, T.; Hayashi, T.; Holynski, R.; Iwai, J.; and others

    1987-02-01

    A hybrid electronic-counter--emulsion-chamber instrument was exposed to high-energy cosmic rays on a balloon. The data on 105 nucleus-nucleus collisions in the energy range 20--65 GeV/nucleon and for incident nuclear charges 22less than or equal toZ/sub p/less than or equal to28 are presented. Inclusive characteristics of particle production on different targets (plastic, emulsion, and lead) are shown and compared with models based on the superposition of nucleon-nucleus interactions. Features of a subset of the more central collisions with plastic target and some characteristics of individual events with the highest multiplicity of produced particles are described.

  16. Nucleus-nucleus potential with shell-correction contribution

    NASA Astrophysics Data System (ADS)

    Denisov, V. Yu.

    2015-02-01

    The full relaxed-density potential between spherical nuclei is considered as a sum of the macroscopic and shell-correction contributions. The macroscopic part of the potential is related to a nucleus-nucleus potential obtained in the framework of the extended Thomas-Fermi approach with the Skyrme and Coulomb forces and the relaxed-density ansatz for evaluation of proton and neutron densities of interacting nuclei. A simple prescription for the shell-correction part of the total potential is discussed. The parameters of the shell-correction and macroscopic parts of the relaxed-density potential are found by fitting the empirical barrier heights of the 89 nucleus-nucleus systems as well as macroscopic potentials evaluated for 1485 nucleus-nucleus systems at 12 distances around touching points.

  17. Nuclear rainbow scattering and nucleus-nucleus potential

    E-print Network

    Dao T. Khoa; W. von Oertzen; H. G. Bohlen; S. Ohkubo

    2006-12-21

    Elastic scattering of alpha-particle and some tightly-bound light nuclei has shown the pattern of rainbow scattering at medium energies, which is due to the refraction of the incident wave by a strongly attractive nucleus-nucleus potential. This review gives an introduction to the physics of the nuclear rainbow based essentially on the optical model description of the elastic scattering. Since the realistic nucleus-nucleus optical potential (OP) is the key to explore this interesting process, an overview of the main methods used to determine the nucleus-nucleus OP is presented. The refractive rainbow-like structures observed in other quasi-elastic scattering reactions have also been discussed. Some evidences for the refractive effect in the elastic scattering of unstable nuclei are presented and perspectives for the future studies are discussed.

  18. Fusion cross sections for reactions involving medium and heavy nucleus-nucleus systems

    NASA Astrophysics Data System (ADS)

    Atta, Debasis; Basu, D. N.

    2014-12-01

    Existing data on near-barrier fusion excitation functions of medium and heavy nucleus-nucleus systems have been analyzed by using a simple diffused-barrier formula derived assuming the Gaussian shape of the barrier-height distributions. The fusion cross section is obtained by folding the Gaussian barrier distribution with the classical expression for the fusion cross section for a fixed barrier. The energy dependence of the fusion cross section, thus obtained, provides good description to the existing data on near-barrier fusion and capture excitation functions for medium and heavy nucleus-nucleus systems. The theoretical values for the parameters of the barrier distribution are estimated which can be used for fusion or capture cross-section predictions that are especially important for planning experiments for synthesizing new superheavy elements.

  19. Higgs-boson production in nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Norbury, J. W.; Townsend, L. W. (Principal Investigator)

    1990-01-01

    Cross-section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two-photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two-photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  20. Higgs-Boson Production in Nucleus-Nucleus Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

  1. Nucleon emission via electromagnetic excitation in relativistic nucleus-nucleus collisions: Re-analysis of the Weizsacker-Williams method

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1989-01-01

    Previous analyses of the comparison of Weizsacker-Williams (WW) theory to experiment for nucleon emission via electromagnetic (EM) excitations in nucleus-nucleus collisions were not definitive because of different assumptions concerning the value of the minimum impact parameter. This situation is corrected by providing criteria that allows definitive statements to be made concerning agreement or disagreement between WW theory and experiment.

  2. Comparison of potential models of nucleus-nucleus bremsstrahlung

    NASA Astrophysics Data System (ADS)

    Dohet-Eraly, J.; Baye, D.

    2014-09-01

    At low photon energies, the potential models of nucleus-nucleus bremsstrahlung are based on electric transition multipole operators, which are derived either only from the nuclear current or only from the charge density by making the long-wavelength approximation and using the Siegert theorem. In the latter case, the bremsstrahlung matrix elements are divergent and some regularization techniques are used to obtain finite values for the bremsstrahlung cross sections. From an extension of the Siegert theorem, which is not based on the long-wavelength approximation, a new potential model of nucleus-nucleus bremsstrahlung is developed. Only convergent integrals are included in this approach. Formal links between bremsstrahlung cross sections obtained in these different models are made. Furthermore, three different ways to calculate the regularized matrix elements are discussed and criticized. Some prescriptions for a proper implementation of the regularization are deduced. A numerical comparison between the different models is done by applying them to the ? +? bremsstrahlung.

  3. Comparison of potential models of nucleus-nucleus bremsstrahlung

    E-print Network

    Jérémy Dohet-Eraly; Daniel Baye

    2014-05-23

    At low photon energies, the potential models of nucleus-nucleus bremsstrahlung are based on electric transition multipole operators, which are derived either only from the nuclear current or only from the charge density by making the long-wavelength approximation and using the Siegert theorem. In the latter case, the bremsstrahlung matrix elements are divergent and some regularization techniques are used to obtain finite values for the bremsstrahlung cross sections. From an extension of the Siegert theorem, which is not based on the long-wavelength approximation, a new potential model of nucleus-nucleus bremsstrahlung is developed. Only convergent integrals are included in this approach. Formal links between bremsstrahlung cross sections obtained in these different models are made. Furthermore, three different ways to calculate the regularized matrix elements are discussed and criticized. Some prescriptions for a proper implementation of the regularization are deduced. A numerical comparison between the different models is done by applying them to the $\\alpha+\\alpha$ bremsstrahlung.

  4. Subthreshold Antiproton Production in Nucleus-Nucleus Collisions

    E-print Network

    LI, GQ; Ko, Che Ming; Fang, X. S.; Zheng, Y. M.

    1994-01-01

    ]. In both calculations [19,20], antiproton annihilation was treated schematically and the propagation as well as the elastic rescattering of antiprotons in the medium were neglected. The underestimation of the antiproton yield in nucleus- nucleus... constants of the nu- cleon to the sigma and omega mesons are denoted, re- spectively, by g and g . The 0.3 and o4 terms represent the scalar meson self-interaction. For a quasihomogeneous and weakly interacting nu- clear system, one can derive a...

  5. TWO-PHOTON PHYSICS IN NUCLEUS-NUCLEUS COLLISIONS AT RHIC.

    SciTech Connect

    NYSTRAND,J.

    1998-09-10

    Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z{sup 2} up to an energy of {approx} 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented.

  6. Nucleus-nucleus collisions at ultra-relativistic energies: Status and prospects

    SciTech Connect

    Plasil, F.

    1995-04-01

    This paper is based on three lectures presented at the Prague Seminar on Relativistic Heavy-Ion Physics in September 1994. The first lecture, following a general introduction, focuses on three different aspects of the CERN experiment WA80. The author first presents results on global event characteristics deduced primarily from measured distributions of transverse energy and of forward energy. The purpose is to introduce the main general features of nucleus-nucleus reactions at the highest energies currently available. He highlights the role of projectile-target geometry, discusses the degree of nuclear stopping, and estimates the energy densities attained in these reactions. This discussion is followed by a presentation of one of two topics that are unique to the WA80 experiment and which are not addressed by any of the other CERN collaborations that study nucleus-nucleus reactions: direct measurements of photons. The second topic unique to WA80, measurements of proton-proton correlations in the target-fragmentation region, is covered in the first part of the second lecture. The remainder of the second lecture is devoted to a selective overview of results obtained at the AGS accelerator of Brookhaven National Laboratory (BNL). The third lecture is devoted to a discussion of the two main experiments, STAR and PHENIX, planned for the Relativistic Heavy Ion Collider, RHIC, under construction at BNL.

  7. Toward a systematic nucleus-nucleus potential for peripheral collisions

    NASA Astrophysics Data System (ADS)

    Xu, Y. P.; Pang, D. Y.

    2013-04-01

    A systematic nucleus-nucleus potential is proposed based on an optical model analysis of angular distributions of differential cross sections of 6Li and 7Li elastic scattering from targets with A?40 with incident energies between 5 and 40 MeV/nucleon. A single-folding model based on the Bruyères Jeukenne-Lejeune-Mahaux (JLMB) model nucleon-nucleus potentials was used. Systematics in energy dependence of the potential parameters were obtained. This systematics was found to give reasonable account for both elastic scattering and total reaction cross sections for projectiles with mass numbers up to A˜40, including both stable and unstable nuclei, for incident energies from the vicinity of the Coulomb barrier to about 100 MeV/nucleon.

  8. Rheology and microstructure of magmatic emulsions - Theory and experiments

    NASA Technical Reports Server (NTRS)

    Stein, Daniel J.; Spera, Frank J.

    1992-01-01

    The rheological properties of a dilute mixture of melt plus vapor bubbles, referred to as emulsion, are investigated theoretically and in rheometric experiments on dilute viscous germanium dioxide emulsions at temperatures between 1100 and 1175 C and at 100 kPa pressure in a rotating rod rheometer at shear rates between 0.05/s and 7/s. The results indicate that the emulsions may be described by a power-law constitutive relation when observations cover a sufficient range of shear rates to resolve nonlinear flow.

  9. Linear extrapolation of ultrarelativistic nucleon-nucleon scattering to nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Jeon, Sangyong; Kapusta, Joseph

    1997-07-01

    We use a Glauber-like approach to describe very energetic nucleus-nucleus collisions as a sequence of binary nucleon-nucleon collisions. No free parameters are needed: All the information comes from simple parametrizations of nucleon-nucleon collision data. Produced mesons are assumed not to interact with each other or with the original baryons. Comparisons are made to published experimental measurements of baryon rapidity and transverse momentum distributions, negative hadron rapidity and transverse momentum distributions, average multiplicities of pions, kaons, hyperons, and antihyperons, and zero degree energy distributions for sulfur-sulfur collisions at 200 GeV/c per nucleon and for lead-lead collisions at 158 GeV/c per nucleon. Good agreement is found except that the number of strange particles produced, especially antihyperons, is too small compared with experiment. We call this model LEXUS: It is a base-line linear extrapolation of ultrarelativistic nucleon-nucleon scattering to heavy ion collisions.

  10. Strangeness Production in Light and Intermediate size Nucleus-Nucleus Collisions

    E-print Network

    M. I. Gorenstein; W. Greiner; A. Rustamov

    2014-05-08

    Within the statistical model, the net strangeness conservation and incomplete total strangeness equilibration lead to the suppression of strange particle multiplicities. Furthermore, suppression effects appear to be stronger in small systems. By treating the production of strangeness within the canonical ensemble formulation we developed a simple model which allows to predict the excitation function of $K^+/\\pi^+$ ratio in nucleus-nucleus collisions. In doing so we assumed that different values of $K^+/\\pi^+$, measured in p+p and Pb+Pb interactions at the same collision energy per nucleon, are driven by the finite size effects only. These predictions may serve as a baseline for experimental results from NA61/SHINE at the CERN SPS and the future CBM experiment at FAIR.

  11. Heavy dilepton in nucleus nucleus collision at LHC energy

    E-print Network

    Majumder, Sarbani

    2013-01-01

    We present a study of $\\tau^+ \\tau^-$ lepton pair production in Pb + Pb collisions at $\\sqrt{s_{NN}}$ = 5.5 TeV. The larger mass of tau lepton compared to electron and muon leads to considerably small hadronic contribution to the $\\tau^+ \\tau^-$ pair invariant mass (M) distribution relative to the production from thermal partonic sources. The quark-antiquark annihilation processes via intermediary virtual photon, Z and Higgs bosons have been considered for the tau lepton production. The contribution from Drell-Yan process is found to dominate over thermal yield for $\\tau^+ \\tau^-$ pair mass from 4 to 20 GeV at the LHC energy. We also present the ratio of $\\tau$ lepton pair yields for nucleus-nucleus collisions relative to yields from p + p collisions scaled by number of binary collisions at LHC energies as a function $\\tau$ lepton pair inavariant mass. The ratio is found to be significantly above unity for the mass range 4 to 6 GeV. This indicates the possibility of detecting $\\tau^+ \\tau^-$ pair from quark g...

  12. The Emulsion Scanning System of the OPERA experiment

    E-print Network

    Juget, F

    2010-01-01

    The OPERA experiment has for goal the direct detection of !? ! !! oscilla- tion, using an hybrid apparatus composed of electronic detectors and nuclear photographic emulsions. A charged particle crossing an emulsion layer ion- izes the medium along its path leaving a latent image which leads, after de- velopment, to a sequence of aligned grains. Nuclear emulsions are analyzed by means of optical microscopes to reconstruct the 3D particle tracks. The OPERA collaboration has developed a dedicated system to scan a large num- ber of emulsions (surface of about 1000 m2). The achieved resolution is "1 ?m and "1 mrad allowing to observe directly the short-lived " particles pro- duced in !!CC interactions.

  13. Emulsion sheet doublets as interface trackers for the OPERA experiment

    E-print Network

    Anokhina, A.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bay, F.; Greggio, F.Bersani; Bertolin, A.; Besnier, M.; Bick, D.; Bozza, C.; Brugiere, T.; Brugnera, R.; Brunetti, G.; Buontempo, S.; Carrara, E.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Consiglio, L.; Cozzi, M.; Cuha, V.; Dal Corso, F.; D'Amato, G.; D'Ambrosio, N.; De Lellis, G.; Declais, Y.; De Serio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Di Troia, C.; Dmitrievski, S.; Dominjon, A.; Dracos, Marcos; Duchesneau, D.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, Antonio; Esposito, L.S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Frekers, D.; Fukuda, T.; Galkin, V.I.; Galkin, V.A.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Goldberg, J.; Golubkov, D.; Gornushkin, Y.; Grella, G.; Grianti, F.; Guler, M.; Gusev, G.; Gustavino, C.; Hagner, Caren; Hara, T.; Hierholzer, M.; Hiramatsu, S.; Hoshino, Kaoru; Ieva, M.; Jakovcic, K.; Janicsko Csathy, J.; Janutta, B.; Jollet, C.; Juget, F.; Kawai, T.; Kazuyama, M.; Kim, S.H.; Knuesel, J.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Laktineh, I.; Lazzaro, C.; Lenkeit, J.; Ljubicic, A.; Longhin, Andrea; Lutter, G.; Manai, K.; Mandrioli, G.; Marotta, A.; Marteau, J.; Matsuo, T.; Matsuoka, H.; Mauri, N.; Meisel, F.; Meregaglia, A.; Messina, M.; Migliozzi, P.; Mikado, S.; Miyamoto, S.; Monacelli, Piero; Morishima, Kunihiro; Moser, U.; Muciaccia, Maria Teresa; Naganawa, N.; Naka, T.; Nakamura, M.; Nakamura, T.; Nakano, T.; Nikitina, V.; Niwa, K.; Nonoyama, Y.; Ogawa, S.; Osedlo, V.; Ossetski, D.; Paoloni, A.; Park, B.D.; Park, I.G.; Pastore, A.; Patrizii, L.; Pennacchio, E.; Pessard, H.; Pilipenko, V.; Pistillo, C.; Polukhina, N.; Pozzato, M.; Pretzl, Klaus P.; Publichenko, P.; Pupilli, F.; Roganova, T.; Rosa, G.; Rostovtseva, I.; Rubbia, A.; Russo, A.; Ryazhskaya, O.; Ryzhikov, D.; Sato, O.; Sato, Y.; Saveliev, V.; Sazhina, G.; Schembri, A.; Scotto Lavina, L.; Shibuya, H.; Simone, S.; Sioli, Max; Sirignano, C.; Sirri, G.; Song, J.S.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strauss, T.; Strolin, Paolo Emilio; Sugonyaev, V.; Taira, Y.; Takahashi, S.; Tenti, M.; Terranova, F.; Tezuka, I.; Tioukov, V.; Tolun, P.; Tsarev, V.; Tufanli, S.; Ushida, N.; Vilain, P.; Vladimirov, M.; Votano, L.; Vuilleumier, J.L.; Wilquet, G.; Wonsak, B.; Wurtz, J.; Yoon, C.S.; Yoshida, J.; Zaitsev, Y.; Zemskova, S.; Zghiche, Amina; Zimmermann, R.

    2008-01-01

    New methods for efficient and unambiguous interconnection between electronic counters and target units based on nuclear photographic emulsion films have been developed. The application to the OPERA experiment, that aims at detecting oscillations between mu neutrino and tau neutrino in the CNGS neutrino beam, is reported in this paper. In order to reduce background due to latent tracks collected before installation in the detector, on-site large-scale treatments of the emulsions ("refreshing") have been applied. Changeable Sheet (CSd) packages, each made of a doublet of emulsion films, have been designed, assembled and coupled to the OPERA target units ("ECC bricks"). A device has been built to print X-ray spots for accurate interconnection both within the CSd and between the CSd and the related ECC brick. Sample emulsion films have been extensively scanned with state-of-the-art automated optical microscopes. Efficient track-matching and powerful background rejection have been achieved in tests with electronic...

  14. Integrated Azimuthal Correlations in Nucleus-Nucleus Collisions at CERN SPS

    E-print Network

    Katarzyna Grebieszkow; Stanislaw Mrowczynski

    2011-10-21

    Azimuthal correlations of particles produced in nucleus-nucleus collisions at CERN SPS are discussed. The correlations quantified by the integral measure Phi are shown to be dominated by effects of collective flow.

  15. Japanese-American Cooperative Emulsion Experiment /JACEE/. [high energy cosmic ray studies

    NASA Technical Reports Server (NTRS)

    Huggett, R. W.; Hunter, S. D.; Jones, W. V.; Takahashi, Y.; Ogata, T.; Saito, T.; Holynski, R.; Jurak, A.; Wolter, W.; Parnell, T. A.

    1981-01-01

    The instrumentation and results of long duration balloon flights carried out jointly by U.S. and Japan researchers to examine high energy cosmic rays are reported. Basic detector geometries are 2.5 sq m sr with operation at altitudes with 3-4 g/sq cm pressure, with observations thus far of over 100 hr. Energies from 2-100 TeV are recorded for nucleus-nucleus and hadron-nucleus interactions, and searches are made for new particle or interactions. The detector is an emulsion chamber which comprises doubly-coated nuclear emulsions on 800 micron thick methacryl substrates, X-ray films, etchable detectors, low density spacers, and lead sheets. Segmentation of the instrument into a primary charge module, a target section, a spacer section, and a lead-emulsion calorimeter allows accurate charge measurement for primary nuclei, reliable energy resolution, and a large geometrical factor for collecting high energy events. A primary Ca nucleus of 300 TeV has been observed.

  16. Pion production at 180/sup 0/ in nucleus-nucleus collisions

    SciTech Connect

    Chessin, S.A.

    1983-05-01

    A survey experiment of pion production at 180/sup 0/ in nucleus-nucleus collisions is presented. Beams of 1.05 GeV/A and 2.1 GeV/A protons, alphas, and carbon were used, as well as proton beams of 0.80 GeV, 3.5 GeV, and 4.89 GeV, and argon beams of 1.05 GeV/A and 1.83 GeV/A. This is the first such experiment to use the heavier beams. Targets used ranged from carbon to lead. An in-depth review of the literature, both experimental and theoretical, is also presented. The systematics of the data are discussed, and comparisons are made both with prior experiments and with the predictions of the models reviewed. The cross sections appear consistent with a simple single nucleon-nucleon collision picture, without the need for collective or other exotic effects. Suggestions for future work are made.

  17. Emulsion sheet doublets as interface trackers for the OPERA experiment

    NASA Astrophysics Data System (ADS)

    Anokhina, A.; Aoki, S.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bay, F.; Bersani Greggio, F.; Bertolin, A.; Besnier, M.; Bick, D.; Bozza, C.; Brugiere, T.; Brugnera, R.; Brunetti, G.; Buontempo, S.; Carrara, E.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Consiglio, L.; Cozzi, M.; Cuha, V.; Dal Corso, F.; D'Amato, G.; D'Ambrosio, N.; DeLellis, G.; Déclais, Y.; DeSerio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Di Troia, C.; Dmitrievski, S.; Dominjon, A.; Dracos, M.; Duchesneau, D.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, A.; Esposito, L. S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Frekers, D.; Fukuda, T.; Galkin, V. I.; Galkin, V. A.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Goldberg, J.; Golubkov, D.; Gornushkin, Y.; Grella, G.; Grianti, F.; Guler, M.; Gusev, G.; Gustavino, C.; Hagner, C.; Hara, T.; Hierholzer, M.; Hiramatsu, S.; Hoshino, K.; Ieva, M.; Jakovcic, K.; Janicsko Csathy, J.; Janutta, B.; Jollet, C.; Juget, F.; Kawai, T.; Kazuyama, M.; Kim, S. H.; Knuesel, J.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Laktineh, I.; Lazzaro, C.; Lenkeit, J.; Ljubicic, A.; Longhin, A.; Lutter, G.; Manai, K.; Mandrioli, G.; Marotta, A.; Marteau, J.; Matsuo, T.; Matsuoka, H.; Mauri, N.; Meisel, F.; Meregaglia, A.; Messina, M.; Migliozzi, P.; Mikado, S.; Miyamoto, S.; Monacelli, P.; Morishima, K.; Moser, U.; Muciaccia, M. T.; Naganawa, N.; Naka, T.; Nakamura, M.; Nakamura, T.; Nakano, T.; Nikitina, V.; Niwa, K.; Nonoyama, Y.; Ogawa, S.; Osedlo, V.; Ossetski, D.; Paoloni, A.; Park, B. D.; Park, I. G.; Pastore, A.; Patrizii, L.; Pennacchio, E.; Pessard, H.; Pilipenko, V.; Pistillo, C.; Polukhina, N.; Pozzato, M.; Pretzl, K.; Publichenko, P.; Pupilli, F.; Roganova, T.; Rosa, G.; Rostovtseva, I.; Rubbia, A.; Russo, A.; Ryazhskaya, O.; Ryzhikov, D.; Sato, O.; Sato, Y.; Saveliev, V.; Sazhina, G.; Schembri, A.; Scotto Lavina, L.; Shibuya, H.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Song, J. S.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strauss, T.; Strolin, P.; Sugonyaev, V.; Taira, Y.; Takahashi, S.; Tenti, M.; Terranova, F.; Tezuka, I.; Tioukov, V.; Tolun, P.; Tsarev, V.; Tufanli, S.; Ushida, N.; Vilain, P.; Vladimirov, M.; Votano, L.; Vuilleumier, J. L.; Wilquet, G.; Wonsak, B.; Yoon, C. S.; Yoshida, J.; Zaitsev, Y.; Zemskova, S.; Zghiche, A.; Zimmermann, R.

    2008-07-01

    New methods for efficient and unambiguous interconnection between electronic position sensitive detectors and target units based on nuclear photographic emulsion films have been developed. The application to the OPERA experiment, that aims at detecting ??rightleftharpoons?? oscillations in the CNGS neutrino beam, is reported in this paper. In order to reduce background due to latent tracks collected before installation in the detector, on-site large-scale treatments of the emulsions (''refreshing'') have been applied. Changeable Sheet (CSd) packages, each made of a doublet of emulsion films, have been designed, assembled and coupled to the OPERA target units (''ECC bricks''). A device has been built to print X-ray spots for accurate interconnection both within the CSd and between the CSd and the related ECC brick. Sample emulsion films have been extensively scanned with state-of-the-art automated optical microscopes. Efficient track-matching and powerful background rejection have been achieved in tests with electronically tagged penetrating muons. Further improvement of in-doublet film alignment was obtained by matching the pattern of low-energy electron tracks. The commissioning of the overall OPERA alignment procedure is in progress.

  18. BFKL Pomeron calculus: solution to equations for nucleus-nucleus scattering in the saturation domain

    E-print Network

    Carlos Contreras; Eugene Levin; Rodrigo Meneses

    2013-02-01

    In this paper we solve the equation for nucleus-nucleus scattering in the BFKL Pomeron calculus, suggested by Braun. We find these solutions analytically at high energies as well as numerically in the entire region of energies inside the saturation region. The semi-classical approximation is used to select out the infinite set of the parasite solutions. The nucleus-nucleus cross sections at high energy are estimated and compared with the Glauber-Gribov approach. It turns out that the exact formula gives the estimates that are very close to the ones based on Glauber-Gribov formula which is important for the practical applications

  19. Computer program for parameterization of nucleus-nucleus electromagnetic dissociation cross sections

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Townsend, Lawrence W.; Badavi, Forooz F.

    1988-01-01

    A computer subroutine parameterization of electromagnetic dissociation cross sections for nucleus-nucleus collisions is presented that is suitable for implementation in a heavy ion transport code. The only inputs required are the projectile kinetic energy and the projectile and target charge and mass numbers.

  20. Skylab experiment performance evaluation manual. Appendix K: Experiment S009 nuclear emulsion (MSFC)

    NASA Technical Reports Server (NTRS)

    Meyers, J. E.

    1972-01-01

    A series of analyses are presented for Experiment S009, nuclear emulsion (MSFC), to be used for evaluating the performance of the Skylab corollary experiments under preflight, inflight, and postflight conditions. Experiment contingency plan workaround procedure and malfunction analyses are included in order to assist in making the experiment operationally successful.

  1. PREFACE: 11th International Conference on Nucleus-Nucleus Collisions (NN2012)

    NASA Astrophysics Data System (ADS)

    Li, Bao-An; Natowitz, Joseph B.

    2013-03-01

    The 11th International Conference on Nucleus-Nucleus Collisions (NN2012) was held from 27 May to 1 June 2012, in San Antonio, Texas, USA. It was jointly organized and hosted by The Cyclotron Institute at Texas A&M University, College Station and The Department of Physics and Astronomy at Texas A&M University-Commerce. Among the approximately 300 participants were a large number of graduate students and post-doctoral fellows. The Keynote Talk of the conference, 'The State of Affairs of Present and Future Nucleus-Nucleus Collision Science', was given by Dr Robert Tribble, University Distinguished Professor and Director of the TAMU Cyclotron Institute. During the conference a very well-received public lecture on neutrino astronomy, 'The ICEcube project', was given by Dr Francis Halzen, Hilldale and Gregory Breit Distinguished Professor at the University of Wisconsin, Madison. The Scientific program continued in the general spirit and intention of this conference series. As is typical of this conference a broad range of topics including fundamental areas of nuclear dynamics, structure, and applications were addressed in 42 plenary session talks, 150 parallel session talks, and 21 posters. The high quality of the work presented emphasized the vitality and relevance of the subject matter of this conference. Following the tradition, the NN2012 International Advisory Committee selected the host and site of the next conference in this series. The 12th International Conference on Nucleus-Nucleus Collisions (NN2015) will be held 21-26 June 2015 in Catania, Italy. It will be hosted by The INFN, Laboratori Nazionali del Sud, INFN, Catania and the Dipartimento di Fisica e Astronomia of the University of Catania. The NN2012 Proceedings contains the conference program and 165 articles organized into the following 10 sections 1. Heavy and Superheavy Elements 2. QCD and Hadron Physics 3. Relativistic Heavy-Ion Collisions 4. Nuclear Structure 5. Nuclear Energy and Applications of Nuclear Science and Technologies 6. Nuclear Reactions and Structure of Unstable Nuclei 7. Equation of State of Neutron-Rich Nuclear Matter, Clusters in Nuclei and Nuclear Reactions 8. Fusion and Fission 9. Nuclear Astrophysics 10. New Facilities and Detectors We would like to thank Texas A&M University and Texas A&M University-Commerce for their organizational support and for providing financial support for many students and postdocs and those who had special need. This support helped assure the success of NN2012. Special thanks also go to all members of the International Advisory Committee and the Local Organizing Committee (listed below) for their great work in advising upon, preparing and executing the NN2012 scientific program as well as the social events that all together made the NN2012 an enjoyable experience for both the participants and their companions. NN2012 International Advisory Committee N Auerbach (Israel) J Aysto (Finland) C Beck (France) S Cherubini (Italy) L Ferreira (Portugal) C Gagliardi (USA) S Gales (France) C Gale (Canada) W Gelletly (Great Britain) Paulo R S Gomes (Brazil) W Greiner (Germany) W Henning (USA) D Hinde (Australia) S Hofmann (Germany) M Hussein (Brazil) B Jacak (USA) S Kailas (India) W G Lynch (USA) Z Majka (Poland) L McLerran (USA) V Metag (Germany) K Morita (Japan) B Mueller (USA) D G Mueller (France) T Motobayashi (Japan) W Nazarewicz (USA) Y Oganessian (Russia) J Nolen (USA) E K Rehm (USA) N Rowley (France) B Sherrill (USA) J Schukraft (Switzerland) W Q Shen (China) A Stefanini (Italy) H Stoecker (Germany) A Szanto de Toledo (Brazil) U van Kolck (USA) W von Oertzen (Germany) M Wiescher (USA) N Xu (USA) N V Zamfir (Romania) W L Zhan (China) H Q Zhang (China) NN2012 Local Organizing Committee Marina Barbui Carlos Bertulani Robert Burch Jr Cheri Davis Cody Folden Kris Hagel John Hardy Bao-An Li (Co-Chair and Scientific Secretary) Joseph Natowitz (Co-Chair) Ralf Rapp Livius Trache Sherry Yennello Editors of NN2012 Proceedings Bao-An Li (Texas A&M University-Commerce) and Joseph Natowitz (Texas A&M Unive

  2. Calorimetry applied to nucleus-nucleus collisions at ultrarelativistic energies

    SciTech Connect

    Plasil, F.

    1988-01-01

    A general introduction to high-energy calorimetry is presented, together with brief descriptions of the two types of cascades relevant to calorimetric measurements. This is followed by a discussion of ''compensation'' and of the ''e/h'' ratio. A detailed description of two calorimeters designed and constructed for the CERN WA80 experiment are also given. 16 refs., 17 figs., 5 tabs.

  3. Classical gluon production amplitude for nucleus-nucleus collisions: First saturation correction in the projectile

    NASA Astrophysics Data System (ADS)

    Chirilli, Giovanni A.; Kovchegov, Yuri V.; Wertepny, Douglas E.

    2015-03-01

    We calculate the classical single-gluon production amplitude in nucleus-nucleus collisions including the first saturation correction in one of the nuclei (the projectile) while keeping multiple-rescattering (saturation) corrections to all orders in the other nucleus (the target). In our approximation only two nucleons interact in the projectile nucleus: the single-gluon production amplitude we calculate is order- g 3 and is leading-order in the atomic number of the projectile, while resumming all order-one saturation corrections in the target nucleus. Our result is the first step towards obtaining an analytic expression for the first projectile saturation correction to the gluon production cross section in nucleus-nucleus collisions.

  4. Momentum loss in proton-nucleus and nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Khan, Ferdous; Townsend, Lawrence W.

    1993-01-01

    An optical model description, based on multiple scattering theory, of longitudinal momentum loss in proton-nucleus and nucleus-nucleus collisions is presented. The crucial role of the imaginary component of the nucleon-nucleon transition matrix in accounting for longitudinal momentum transfer is demonstrated. Results obtained with this model are compared with Intranuclear Cascade (INC) calculations, as well as with predictions from Vlasov-Uehling-Uhlenbeck (VUU) and quantum molecular dynamics (QMD) simulations. Comparisons are also made with experimental data where available. These indicate that the present model is adequate to account for longitudinal momentum transfer in both proton-nucleus and nucleus-nucleus collisions over a wide range of energies.

  5. Parameter scaling test of a dynamic nucleus-nucleus collision theory

    Microsoft Academic Search

    Brunon Sikora; Jens Bisplinghoff; Marshall Blann; Wolfgang Scobel; Martin Beckerman; Franz Plasil; Robert L. Ferguson; John Birkelund; Winfried Wilcke

    1982-01-01

    A new dynamic nucleus-nucleus interaction model due to Swiatecki is used to predict fusion excitation functions resulting from 35Cl bombardments of 62Ni, 116Sn, and 141Pr. Agreement supports the universal scaling parameter concept of the new model. NUCLEAR REACTIONS 35Cl+62Ni, 116Sn, 141Pr ?LAB=155-300 MeV. Measured evaporation residue and fissionlike cross sections. Compare with Swiatecki's dynamic fusion model.

  6. Random Matrix Theory and Analysis of Nucleus-Nucleus Collision at High Energies

    E-print Network

    E. I. Shahaliev; R. G. Nazmitdinov; A. A. Kuznetsov; M. K. Suleymanov; O. V. Teryaev

    2005-02-04

    We propose a novel method for analysis of experimental data obtained at relativistic nucleus-nucleus collisions. The method, based on the ideas of Random Matrix Theory, is applied to detect systematic errors that occur at measurements of momentum distributions of emitted particles. The unfolded momentum distribution is well described by the Gaussian orthogonal ensemble of random matrices, when the uncertainty in the momentum distribution is maximal. The method is free from unwanted background contributions.

  7. Sensitivity of Cross Sections for Elastic Nucleus-Nucleus Scattering to Halo Nucleus Density Distributions

    E-print Network

    G. D. Alkhazov; V. V. Sarantsev

    2011-07-04

    In order to clear up the sensitivity of the nucleus-nucleus scattering to the nuclear matter distributions of exotic halo nuclei, we have calculated differential cross sections for elastic scattering of the $^6$He and $^{11}$Li nuclei on several nuclear targets at the energy of 0.8 GeV/nucleon with different assumed nuclear density distributions in $^6$He and $^{11}$Li.

  8. Analysis of nucleus-nucleus collisions at high energies and Random Matrix Theory

    E-print Network

    R. G. Nazmitdinov; E. I. Shahaliev; M. K. Suleymanov; S. Tomsovic

    2009-05-07

    We propose a novel statistical approach to the analysis of experimental data obtained in nucleus-nucleus collisions at high energies which borrows from methods developed within the context of Random Matrix Theory. It is applied to the detection of correlations in momentum distributions of emitted particles. We find good agreement between the results obtained in this way and a standard analysis based on the method of effective mass spectra and two-pair correlation function often used in high energy physics. The method introduced here is free from unwanted background contributions.

  9. Study on chemical equilibrium in nucleus-nucleus collisions at relativistic energies

    E-print Network

    Jaakko Manninen; Francesco Becattini; Antti Keranen; Marek Gazdzicki; Reinhard Stock

    2004-05-06

    We present a detailed study of chemical freeze-out in nucleus-nucleus collisions at beam energies of 11.6, 30, 40, 80 and 158A GeV. By analyzing hadronic multiplicities within the statistical hadronization approach, we have studied the chemical equilibration of the system as a function of center of mass energy and of the parameters of the source. Additionally, we have tested and compared different versions of the statistical model, with special emphasis on possible explanations of the observed strangeness hadronic phase space under-saturation.

  10. Electromagnetic processes in nucleus-nucleus collisions relating to space radiation research

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Most of the papers within this report deal with electromagnetic processes in nucleus-nucleus collisions which are of concern in the space radiation program. In particular, the removal of one and two nucleons via both electromagnetic and strong interaction processes has been extensively investigated. The theory of relativistic Coulomb fission has also been developed. Several papers on quark models also appear. Finally, note that the theoretical methods developed in this work have been directly applied to the task of radiation protection of astronauts. This has been done by parameterizing the theoretical formalism in such a fashion that it can be used in cosmic ray transport codes.

  11. Pion and Kaon Lab Frame Differential Cross Sections for Intermediate Energy Nucleus-Nucleus Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Blattnig, Steve R.

    2008-01-01

    Space radiation transport codes require accurate models for hadron production in intermediate energy nucleus-nucleus collisions. Codes require cross sections to be written in terms of lab frame variables and it is important to be able to verify models against experimental data in the lab frame. Several models are compared to lab frame data. It is found that models based on algebraic parameterizations are unable to describe intermediate energy differential cross section data. However, simple thermal model parameterizations, when appropriately transformed from the center of momentum to the lab frame, are able to account for the data.

  12. Extraction of nucleus-nucleus potential and energy dissipation from dynamical mean-field theory

    SciTech Connect

    Washiyama, Kouhei; Lacroix, Denis [GANIL, BP55027, 14076 Caen (France)

    2009-03-04

    Nucleus-nucleus interaction potentials in heavy-ion fusion reactions are extracted from the microscopic time-dependent Hartree-Fock theory. When the center-of-mass energy is much higher than the Coulomb barrier energy, extracted potentials identify with the frozen density approximation. As the center-of-mass energy decreases to the Coulomb barrier energy, potentials become energy dependent. This dependence indicates dynamical reorganization of internal degrees of freedom and leads to a reduction of the ''apparent'' barrier. Including this effect leads to the Coulomb barrier energy very close to experimental one. Aspects of one-body energy dissipation extracted from the mean-field theory are discussed.

  13. The Nuclear Emulsion Technology and the Analysis of the OPERA Experiment Data

    E-print Network

    Tsutomu Fukuda

    2009-10-17

    OPERA is an experiment that aims at detecting the appearance of tau-neutrino in an almost pure mu-neutrino beam (the CNGS neutrino beam) through oscillation. OPERA is a hybrid detector that associates nuclear emulsions to electronic detectors. The nuclear emulsion provides the resolution necessary to detect tau-neutrino CC interactions. The first physics run started in July and ended in November 2008. In this presentation, the status of the emulsion technology and of the analysis of its data is reported.

  14. Investigation of high p$_{t}$ events in Nucleus-Nucleus collisions using the Hijing event generator

    E-print Network

    Natasha Sharma; Madan M. Aggarwal

    2009-10-29

    In recent years lot of interest has been observed in the nucleus-nucleus collisions at RHIC energies in phenomena related to high $p_{t}$ physics \\cite{ref1}. The suppression of high $p_{t}$ particles and disappearance of back-to-back jets compared to the scaling with number of binary nucleon-nucleon collisions indicates that a nearly perfect liquid is produced in these collisions. Results on self shadowing of high $p_{t}$ events are presented using hadron multiplicity associated to high $p_{t}$ and unbiased events in nucleus-nucleus collisions \\cite{ref2} obtained from the hijing event generator.

  15. Nucleus-nucleus Bremsstrahlung from scattering angle selected Cl-Sn collisions

    SciTech Connect

    Gaukler, G.; Nolte, G.; Schuch, R.

    1986-01-01

    Continuum X rays above the K lines of Sn were measured at 90 and 0/sup 0/ angle relative to the incident beam direction in coincidence with C1 projectiles scattered at very large laboratory angles between 8 and 164/sup 0/. By varying the isotope mass of the projectile ions (/sup 35/Cl and /sup 37/Cl) and of the target atoms (/sup 112/Sn and /sup 118/Sn) the radiation at scattering angles >10/sup 0/ could be clearly identified as Bremsstrahlung from the elementary scattering process of the two nuclei. The intensity of the radiation emitted at 0 and 90/sup 0/ relative to the beam direction can be reasonably well described by a quantum mechanical calculation of nucleus-nucleus Bremsstrahlung which includes the interference between dipole and quadrupole radiation amplitude. 10 refs., 4 figs., 1 tab.

  16. A scaling relation between proton-nucleus and nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Ba?ar, Gökçe; Teaney, Derek

    2014-11-01

    It is recently discovered that at high multiplicity, the proton-nucleus (pA) collisions give rise to two particle correlations that are strikingly similar to those of nucleus-nucleus (AA) collisions at the same multiplicity, although the system size is smaller in pA. Using an independent cluster model and a simple conformal scaling argument, where the ratio of the mean free path to the system size stays constant at fixed multiplicity, we argue that flow in pA emerges as a collective response to the fluctuations in the position of clusters, just like in AA collisions. With several physically motivated and parameter free rescalings of the recent LHC data, we show that this simple model captures the essential physics of elliptic and triangular flow in pA collisions.

  17. Statistical analysis of secondary particle distributions in relativistic nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1987-01-01

    The use is described of several statistical techniques to characterize structure in the angular distributions of secondary particles from nucleus-nucleus collisions in the energy range 24 to 61 GeV/nucleon. The objective of this work was to determine whether there are correlations between emitted particle intensity and angle that may be used to support the existence of the quark gluon plasma. The techniques include chi-square null hypothesis tests, the method of discrete Fourier transform analysis, and fluctuation analysis. We have also used the method of composite unit vectors to test for azimuthal asymmetry in a data set of 63 JACEE-3 events. Each method is presented in a manner that provides the reader with some practical detail regarding its application. Of those events with relatively high statistics, Fe approaches 0 at 55 GeV/nucleon was found to possess an azimuthal distribution with a highly non-random structure. No evidence of non-statistical fluctuations was found in the pseudo-rapidity distributions of the events studied. It is seen that the most effective application of these methods relies upon the availability of many events or single events that possess very high multiplicities.

  18. Chemical equilibrium study in nucleus-nucleus collisions at relativistic energies

    E-print Network

    F. Becattini; M. Gazdzicki; A. Keranen; J. Manninen; R. Stock

    2004-03-26

    We present a detailed study of chemical freeze-out in nucleus-nucleus collisions at beam energies of 11.6, 30, 40, 80 and 158A GeV. By analyzing hadronic multiplicities within the statistical hadronization approach, we have studied the strangeness production as a function of centre of mass energy and of the parameters of the source. We have tested and compared different versions of the statistical model, with special emphasis on possible explanations of the observed strangeness hadronic phase space under-saturation. We show that, in this energy range, the use of hadron yields at midrapidity instead of in full phase space artificially enhances strangeness production and could lead to incorrect conclusions as far as the occurrence of full chemical equilibrium is concerned. In addition to the basic model with an extra strange quark non-equilibrium parameter, we have tested three more schemes: a two-component model superimposing hadrons coming out of single nucleon-nucleon interactions to those emerging from large fireballs at equilibrium, a model with local strangeness neutrality and a model with strange and light quark non-equilibrium parameters. The behaviour of the source parameters as a function of colliding system and collision energy is studied. The description of strangeness production entails a non-monotonic energy dependence of strangeness saturation parameter gamma_S with a maximum around 30A GeV. We also present predictions of the production rates of still unmeasured hadrons including the newly discovered Theta^+(1540) pentaquark baryon.

  19. Energy dependence of the nucleus-nucleus potential close to the Coulomb barrier

    SciTech Connect

    Washiyama, Kouhei [GANIL, CEA and IN2P3, Boite Postale 55027, F-14076 Caen Cedex 5 (France); Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Lacroix, Denis [GANIL, CEA and IN2P3, Boite Postale 55027, F-14076 Caen Cedex 5 (France)

    2008-08-15

    The nucleus-nucleus interaction potentials in heavy-ion fusion reactions are extracted from the microscopic time-dependent Hartree-Fock theory for the mass symmetric reactions {sup 16}O + {sup 16}O, {sup 40}Ca + {sup 40}Ca, and {sup 48}Ca + {sup 48}Ca and the mass asymmetric reactions {sup 16}O + {sup 40,} {sup 48}Ca, {sup 40}Ca + {sup 48}Ca, {sup 16}O + {sup 208}Pb, and {sup 40}Ca + {sup 90}Zr. When the c.m. energy is much higher than the Coulomb barrier energy, potentials deduced with the microscopic theory identify with the frozen density approximation. As the c.m. energy decreases and approaches the Coulomb barrier, potentials become energy dependent. This dependence indicates dynamical reorganization of internal degrees of freedom and leads to a reduction of the 'apparent' barrier felt by the two nuclei during fusion of the order of 2-3% compared to the frozen density case. Several examples illustrate that the potential landscape changes rapidly when the c.m. energy is in the vicinity of the Coulomb barrier energy. The energy dependence is expected to have a significant role on fusion around the Coulomb barrier.

  20. Heavy-flavor dynamics in nucleus-nucleus collisions: from the RHIC to the LHC

    NASA Astrophysics Data System (ADS)

    Monteno, M.; Alberico, W. M.; Beraudo, A.; De Pace, A.; Molinari, A.; Nardi, M.; Prino, F.

    2011-12-01

    The stochastic dynamics of c and b quarks in the fireball created in nucleus-nucleus collisions at the RHIC and LHC is studied employing a relativistic Langevin equation, based on a picture of multiple uncorrelated random collisions with the medium. Heavy-quark transport coefficients are evaluated within a pQCD approach, with a proper HTL resummation of medium effects for soft scatterings. The Langevin equation is embedded in a multi-step setup developed to study heavy-flavor observables in pp and AA collisions, starting from a NLO pQCD calculation of initial heavy-quark yields, complemented in the nuclear case by shadowing corrections, kT-broadening and nuclear geometry effects. Then, only for AA collisions, the Langevin equation is solved numerically in a background medium described by relativistic hydrodynamics. Finally, the propagated heavy quarks are made hadronize and decay into electrons. Results for the nuclear modification factor RAA of heavy-flavor hadrons and electrons from their semi-leptonic decays are provided, both for RHIC and LHC beam energies.

  1. Energy-Dependence of Nucleus-Nucleus Potential and Friction Parameter in Fusion Reactions

    E-print Network

    Kai Wen; Fumihiko Sakata; Zhu-Xia Li; Xi-Zhen Wu; Ying-Xun Zhang; Shan-Gui Zhou

    2014-11-08

    Applying a macroscopic reduction procedure on the improved quantum molecular dynamics (ImQMD) model, the energy dependences of the nucleus-nucleus potential, the friction parameter, and the random force characterizing a one-dimensional Langevin-type description of the heavy-ion fusion process are investigated. Systematic calculations with the ImQMD model show that the fluctuation-dissipation relation found in the symmetric head-on fusion reactions at energies just above the Coulomb barrier fades out when the incident energy increases. It turns out that this dynamical change with increasing incident energy is caused by a specific behavior of the friction parameter which directly depends on the microscopic dynamical process, i.e., on how the collective energy of the relative motion is transferred into the intrinsic excitation energy. It is shown microscopically that the energy dissipation in the fusion process is governed by two mechanisms: One is caused by the nucleon exchanges between two fusing nuclei, and the other is due to a rearrangement of nucleons in the intrinsic system. The former mechanism monotonically increases the dissipative energy and shows a weak dependence on the incident energy, while the latter depends on both the relative distance between two fusing nuclei and the incident energy. It is shown that the latter mechanism is responsible for the energy dependence of the fusion potential and explains the fading out of the fluctuation-dissipation relation.

  2. JACEE long duration balloon flights. [Japanese-American Cooperative Emulsion Experiment

    NASA Technical Reports Server (NTRS)

    Burnett, T.; Iwai, J.; Dake, S.; Derrickson, J.; Fountain, W.; Fuki, M.; Gregory, J.; Hayashi, T.; Holynski, R.; Jones, W. V.

    1989-01-01

    JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1 to 100A TeV. Experiments with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed.

  3. Stopping powers and cross sections due to two-photon processes in relativistic nucleus-nucleus collisions

    NASA Technical Reports Server (NTRS)

    Cheung, Wang K.; Norbury, John W.

    1994-01-01

    The effects of electromagnetic-production processes due to two-photon exchange in nucleus-nucleus collisions are discussed. Feynman diagrams for two-photon exchange are evaluated using quantum electrodynamics. The total cross section and stopping power for projectile and target nuclei of identical charge are found to be significant for heavy nuclei above a few GeV per nucleon-incident energy.

  4. Formation of dense partonic matter in relativistic nucleus–nucleus collisions at RHIC: Experimental evaluation by the PHENIX Collaboration

    Microsoft Academic Search

    K. Adcox; S. S. Adler; S. Afanasiev; C. Aidala; N. N. Ajitanand; Y. Akiba; A. Al-Jamel; J. Alexander; R. Amirikas; K. Aoki; L. Aphecetche; Y. Arai; R. Armendariz; S. H. Aronson; R. Averbeck; T. C. Awes; R. Azmoun; V. Babintsev; A. Baldisseri; K. N. Barish; P. D. Barnes; J. Barrette; B. Bassalleck; S. Bathe; S. Batsouli; V. Baublis; F. Bauer; A. Bazilevsky; S. Belikov; F. G. Bellaiche; S. T. Belyaev; M. J. Bennett; Y. Berdnikov; S. Bhagavatula; M. T. Bjorndal; J. G. Boissevain; H. Borel; S. Borenstein; M. L. Brooks; D. S. Brown; N. Bruner; D. Bucher; H. Buesching; V. Bumazhnov; G. Bunce; J. M. Burward-Hoy; S. Butsyk; X. Camard; T. A. Carey; J.-S. Chai; P. Chand; J. Chang; W. C. Chang; L. L. Chavez; S. Chernichenko; C. Y. Chi; J. Chiba; M. Chiu; I. J. Choi; R. K. Choudhury; T. Christ; M. S. Chung; P. Chung; V. Cianciolo; C. R. Cleven; Y. Cobigo; B. A. Cole; M. P. Comets; P. Constantin; M. Csanád; T. Csörg?; J. P. Cussonneau; D. d'Enterria; T. Dahms; K. Das; G. David; F. Deák; H. Delagrange; A. Denisov; A. Deshpande; E. J. Desmond; A. Devismes; O. Dietzsch; B. V. Dinesh; J. L. Drachenberg; O. Drapier; A. Drees; A. K. Dubey; R. du Rietz; A. Durum; D. Dutta; V. Dzhordzhadze; K. Ebisu; Y. V. Efremenko; J. Egdemir; K. El Chenawi; A. Enokizono; H. En'yo; B. Espagnon; S. Esumi; L. Ewell; T. Ferdousi; D. E. Fields; C. Finck; F. Fleuret; S. L. Fokin; B. Forestier; Z. Fraenkel; J. E. Frantz; A. Franz; A. D. Frawley; Y. Fukao; S.-Y. Fung; S. Gadrat; S. Garpman; F. Gastineau; M. Germain; T. K. Ghosh; A. Glenn; A. L. Godoi; G. Gogiberidze; M. Gonin; J. Gosset; Y. Goto; R. Granier de Cassagnac; N. Grau; S. V. Greene; M. Grosse Perdekamp; T. Gunji; S. K. Gupta; W. Guryn; H.-Å. Gustafsson; T. Hachiya; A. Hadjhenni; J. S. Haggerty; M. N. Hagiwara; H. Hamagaki; A. G. Hansen; H. Hara; H. Harada; E. P. Hartouni; K. Haruna; M. Harvey; E. Haslum; K. Hasuko; R. Hayano; N. Hayashi; X. He; M. Heffner; T. K. Hemmick; J. M. Heuser; P. Hidas; H. Hiejima; J. C. Hill; D. S. Ho; R. Hobbs; M. Holmes; W. Holzmann; K. Homma; B. Hong; A. Hoover; T. Horaguchi; H. M. Hur; T. Ichihara; V. V. Ikonnikov; K. Imai; M. Inaba; M. Inuzuka; M. S. Ippolitov; D. Isenhower; L. Isenhower; M. Ishihara; T. Isobe; M. Issah; A. Isupov; B. V. Jacak; W. Y. Jang; J. Jia; O. Jinnouchi; B. M. Johnson; S. C. Johnson; K. S. Joo; D. Jouan; F. Kajihara; S. Kametani; N. Kamihara; M. Kaneta; J. H. Kang; M. Kann; S. S. Kapoor; K. Katou; T. Kawabata; T. Kawagishi; A. V. Kazantsev; S. Kelly; B. Khachaturov; A. Khanzadeev; J. Kikuchi; D. H. Kim; D. J. Kim; D. W. Kim; E. Kim; G.-B. Kim; H. J. Kim; S. Y. Kim; Y. G. Kim; E. Kinney; W. W. Kinnison; A. Kiss; E. Kistenev; A. Kiyomichi; K. Kiyoyama; C. Klein-Boesing; S. Klinksiek; H. Kobayashi; L. Kochenda; V. Kochetkov; D. Koehler; T. Kohama; R. Kohara; B. Komkov; M. Konno; M. Kopytine; D. Kotchetkov; A. Kozlov; P. J. Kroon; C. H. Kuberg; G. J. Kunde; N. Kurihara; K. Kurita; Y. Kuroki; M. J. Kweon; Y. Kwon; G. S. Kyle; R. Lacey; V. Ladygin; J. G. Lajoie; J. Lauret; Y. Le Bornec; A. Lebedev; S. Leckey; D. M. Lee; S. Lee; M. J. Leitch; M. A. L. Leite; X. H. Li; Z. Li; D. J. Lim; H. Lim; A. Litvinenko; M. X. Liu; X. Liu; X. Liu; Z. Liu; C. F. Maguire; J. Mahon; Y. I. Makdisi; A. Malakhov; M. D. Malik; V. I. Manko; Y. Mao; S. K. Mark; S. Markacs; G. Martinez; M. D. Marx; A. Masaike; H. Masui; F. Matathias; T. Matsumoto; M. C. McCain; P. L. McGaughey; E. Melnikov; M. Merschmeyer; F. Messer; M. Messer; Y. Miake; J. Milan; T. E. Miller; A. Milov; S. Mioduszewski; R. E. Mischke; G. C. Mishra; J. T. Mitchell; A. K. Mohanty; D. P. Morrison; J. M. Moss; T. V. Moukhanova; F. Mühlbacher; D. Mukhopadhyay; M. Muniruzzaman; J. Murata; S. Nagamiya; Y. Nagasaka; J. L. Nagle; M. Naglis; Y. Nakada; T. Nakamura; B. K. Nandi; M. Nara; J. Newby; M. Nguyen; L. Nikkinen; P. Nilsson; S. Nishimura; B. Norman; A. S. Nyanin; J. Nystrand; E. O'Brien; C. A. Ogilvie; H. Ohnishi; I. D. Ojha; H. Okada; K. Okada; O. O. Omiwade; M. Ono; V. Onuchin; A. Oskarsson; L. Österman; I. Otterlund; K. Oyama; L. Paffrath; D. Pal; A. P. T. Palounek; V. Pantuev; V. Papavassiliou; W. J. Park; A. Parmar; S. F. Pate; H. Pei; T. Peitzmann; V. Penev; J.-C. Peng; H. Pereira; V. Peresedov; D. Yu. Peressounko; A. N. Petridis; A. Pierson; C. Pinkenburg; R. P. Pisani; F. Plasil; M. Pollack; K. Pope; M. L. Purschke; A. K. Purwar; H. Qu; J. M. Qualls; J. Rak; I. Ravinovich; K. F. Read; M. Reuter; K. Reygers; V. Riabov; G. Roche; A. Romana; M. Rosati; A. A. Rose; S. S. E. Rosendahl; P. Rosnet; P. Rukoyatkin; V. L. Rykov; S. S. Ryu; M. E. Sadler; B. Sahlmueller; N. Saito; A. Sakaguchi; T. Sakaguchi; M. Sakai; S. Sakai; H. Sako; T. Sakuma; V. Samsonov; L. Sanfratello; T. C. Sangster; R. Santo; H. D. Sato; S. Sato; S. Sawada; B. R. Schlei; Y. Schutz; V. Semenov; R. Seto; D. Sharma; M. R. Shaw; T. K. Shea; I. Shein; T.-A. Shibata; K. Shigaki; T. Shiina

    2005-01-01

    Extensive experimental data from high-energy nucleus-nucleus collisions were recorded using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The comprehensive set of measurements from the first three years of RHIC operation includes charged particle multiplicities, transverse energy, yield ratios and spectra of identified hadrons in a wide range of transverse momenta (pT), elliptic flow, two-particle correlations, nonstatistical fluctuations,

  5. Photoproduction of lepton pairs in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies

    SciTech Connect

    Moreira, B. D.; Goncalves, V. P.; De Santana Amaral, J. T. [Universidade Federal de Pelotas, Instituto de Fisica e Matematica (Brazil)

    2013-03-25

    In this contribution we study coherent interactions as a probe of the nonlinear effects in the Quantum Electrodynamics (QED). In particular, we study the multiphoton effects in the production of leptons pairs for proton-nucleus and nucleus-nucleus collisions for heavy nuclei. In the proton-nucleus we assume the ultrarelativistic proton as a source of photons and estimate the photoproduction of lepton pairs on nuclei at RHIC and LHC energies considering the multiphoton effects associated to multiple rescattering of the projectile photon on the proton of the nucleus. In nucleus - nucleus colllisions we consider the two nuclei as a source of photons. As each scattering contributes with a factor {alpha}Z to the cross section, this contribution must be taken into account for heavy nuclei. We consider the Coulomb corrections to calculate themultiple scatterings and estimate the total cross section for muon and tau pair production in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies.

  6. Kinematical analysis with the Emulsion Cloud Chamber in the OPERA experiment

    E-print Network

    Di Capua, F

    2010-01-01

    The OPERA experiment aims at measuring for the first time neutrino oscil- lation in appearance mode through the detection of ni-tau in an almost pure ni? beam produced at CERN SPS (CNGS), 730 km far from the detector. The ni-tau appearance signal is identified through the measurement of the decay daughter particles of the " lepton produced in CC ni-tau interactions. Since the short-lived " particle has, at the energy of the beam, an average decay length shorter than a 1 mm, a micrometric detection resolution is needed. The OPERA appara- tus is hybrid, using nuclear emulsion as high precision tracker and electronic detectors for the time stamp, event localization in the target and muon recon- struction. The Emulsion Cloud Chamber technique fulfils the requirement of a microscopic resolution together with a large target mass. The kinematical analysis allowed by this technique is described.

  7. Development of nuclear emulsions with 1 ?m spatial resolution for the AEgIS experiment

    NASA Astrophysics Data System (ADS)

    Kimura, M.; Aghion, S.; Ahlén, O.; Amsler, C.; Ariga, A.; Ariga, T.; Belov, A. S.; Bonomi, G.; Bräunig, P.; Bremer, J.; Brusa, R. S.; Burghart, G.; Cabaret, L.; Canali, C.; Caravita, R.; Castelli, F.; Cerchiari, G.; Cialdi, S.; Comparat, D.; Consolati, G.; Di Domizio, S.; Di Noto, L.; Doser, M.; Dudarev, A.; Ereditato, A.; Ferragut, R.; Fontana, A.; Genova, P.; Giammarchi, M.; Gligorova, A.; Gninenko, S. N.; Haider, S.; Hogan, S. D.; Huse, T.; Jordan, E.; Jørgensen, L. V.; Kaltenbacher, T.; Kawada, J.; Kellerbauer, A.; Knecht, A.; Krasnický, D.; Lagomarsino, V.; Mariazzi, S.; Matveev, V. A.; Merkt, F.; Moia, F.; Nebbia, G.; Nédélec, P.; Oberthaler, M. K.; Pacifico, N.; Petrá?ek, V.; Pistillo, C.; Prelz, F.; Prevedelli, M.; Regenfus, C.; Riccardi, C.; Røhne, O.; Rotondi, A.; Sandaker, H.; Scampoli, P.; Storey, J.; Subieta Vasquez, M. A.; Špa?ek, M.; Testera, G.; Trezzi, D.; Vaccarone, R.; Zavatarelli, S.

    2013-12-01

    The main goal of the AEgIS experiment at CERN is to test the weak equivalence principle for antimatter. We will measure the Earth's gravitational acceleration gbar with antihydrogen atoms being launched in a horizontal vacuum tube and traversing a moiré deflectometer. We intend to use a position sensitive device made of nuclear emulsions (combined with a time-of-flight detector such as silicon ?-strips) to measure precisely their annihilation points at the end of the tube. The goal is to determine gbar with a 1% relative accuracy. In 2012 we tested emulsion films in vacuum and at room temperature with low energy antiprotons from the CERN antiproton decelerator. First results on the expected performance for AEgIS are presented.

  8. Recent Emulsion Technologies

    SciTech Connect

    Ariga, A. [A. Einstein Center for Fundamental Physics, LHEP, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland)

    2011-10-06

    Emulsion technologies are very much developed in the last decade and still developing in both the emulsion gel and the data taking. Emulsion detectors are suitable for the neutrino experiments because they can distinguish all 3 flavors of neutrino. The OPERA experiment, a recent pillar in the emulsion experiments aiming at the first observation of the neutrino oscillation in CNGS beam in appearance mode, is running, showing the good capability to separate 3 flavor neutrino interactions. In this poster, the recent developments and prospects of the emulsions for the next generation experiments are reported.

  9. Production of Kaon and $?$ in nucleus-nucleus collisions at ultra-relativistic energy from a blast wave model

    E-print Network

    Song Zhang; Yu-Gang Ma; Jin-Hui Chen; Chen Zhong

    2014-11-06

    The particle production of Kaon and $\\Lambda$ are studied in nucleus-nucleus collisions at relativistic energy based on a chemical equilibrium blast-wave model. The transverse momentum spectra of Kaon and $\\Lambda$ at the kinetic freeze-out stage from our model are in good agreement with the experimental results. The kinetic freeze-out parameters of temperature ($T_{kin}$) and radial flow parameter $\\rho_{0}$ are presented for the FOPI, RHIC and LHC energies. And the resonance decay effect is also discussed. The systematic study for beam energy dependence of the strangeness particle production will help us to better understand the properties of the matter created in heavy-ion collisions at the kinetic freeze-out stage.

  10. Dielectron Cross Section Measurements in Nucleus-Nucleus Reactions at 1.0{ital A} GeV

    SciTech Connect

    Porter, R.J.; Bossingham, R.; Gong, W.G.; Heilbronn, L.; Huang, H.Z.; Krebs, G.; Letessier-Selvon, A.; Matis, H.S.; Miller, J.; Naudet, C.; Roche, G.; Schroeder, L.S.; Seidl, P.; Wilson, W.K.; Yegneswaran, A. [Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States)] [Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States); Beedoe, S.; Carroll, J.; Huang, H.Z.; Igo, G. [University of California at Los Angeles, California 90095 (United States)] [University of California at Los Angeles, California 90095 (United States); Bougteb, M.; Manso, F.; Prunet, M.; Roche, G. [Universite Blaise Pascal/IN2P3, 63177 Aubiere Cedex (France)] [Universite Blaise Pascal/IN2P3, 63177 Aubiere Cedex (France); Christie, W.B.; Hallman, T.; Madansky, L.; Welsh, R.C. [The Johns Hopkins University, Baltimore, Maryland 21218 (United States)] [The Johns Hopkins University, Baltimore, Maryland 21218 (United States); Kirk, P.; Wang, Z.F. [Louisiana State University, Baton Rouge, Louisiana 70803 (United States)] [Louisiana State University, Baton Rouge, Louisiana 70803 (United States); Wilson, W.K. [Wayne State University, Detroit, Michigan 48201 (United States)] [Wayne State University, Detroit, Michigan 48201 (United States)

    1997-08-01

    We present measured dielectron production cross sections for Ca+Ca, C+C, He+Ca, and d+Ca reactions at 1.0 A GeV . Statistical uncertainties and systematic effects are smaller than in previous dilepton spectrometer (DLS) nucleus-nucleus data. For pair mass M{le}0.35 GeV/c{sup 2} we obtain (1) the Ca+Ca cross section is larger than the previous DLS measurement and current model results, (2) the mass spectra suggest large contributions from {pi}{sup 0} and {eta} Dalitz decays, and (3) d{sigma}/dM{proportional_to}A{sub P}A{sub T}. For M{gt}0.5 GeV/c{sup 2} the Ca+Ca to C+C cross section ratio is significantly larger than the ratio of A{sub P}A{sub T} values. {copyright} {ital 1997} {ital The American Physical Society}

  11. Global optical potential for nucleus-nucleus systems from 50 MeV/u to 400 MeV/u

    E-print Network

    T. Furumoto; W. Horiuchi; M. Takashina; Y. Yamamoto; Y. Sakuragi

    2012-04-10

    We present a new global optical potential (GOP) for nucleus-nucleus systems, including neutron-rich and proton-rich isotopes, in the energy range of $50 \\sim 400$ MeV/u. The GOP is derived from the microscopic folding model with the complex $G$-matrix interaction CEG07 and the global density presented by S{\\~ a}o Paulo group. The folding model well accounts for realistic complex optical potentials of nucleus-nucleus systems and reproduces the existing elastic scattering data for stable heavy-ion projectiles at incident energies above 50 MeV/u. We then calculate the folding-model potentials (FMPs) for projectiles of even-even isotopes, $^{8-22}$C, $^{12-24}$O, $^{16-38}$Ne, $^{20-40}$Mg, $^{22-48}$Si, $^{26-52}$S, $^{30-62}$Ar, and $^{34-70}$Ca, scattered by stable target nuclei of $^{12}$C, $^{16}$O, $^{28}$Si, $^{40}$Ca $^{58}$Ni, $^{90}$Zr, $^{120}$Sn, and $^{208}$Pb at the incident energy of 50, 60, 70, 80, 100, 120, 140, 160, 180, 200, 250, 300, 350, and 400 MeV/u. The calculated FMP is represented, with a sufficient accuracy, by a linear combination of 10-range Gaussian functions. The expansion coefficients depend on the incident energy, the projectile and target mass numbers and the projectile atomic number, while the range parameters are taken to depend only on the projectile and target mass numbers. The adequate mass region of the present GOP by the global density is inspected in comparison with FMP by realistic density. The full set of the range parameters and the coefficients for all the projectile-target combinations at each incident energy are provided on a permanent open-access website together with a Fortran program for calculating the microscopic-basis GOP (MGOP) for a desired projectile nucleus by the spline interpolation over the incident energy and the target mass number.

  12. Development of nuclear emulsions operating in vacuum for the AEgIS experiment

    NASA Astrophysics Data System (ADS)

    Scampoli, P.; Aghion, S.; Ahlén, O.; Amsler, C.; Ariga, A.; Ariga, T.; Belov, A. S.; Berggren, K.; Bonomi, G.; Bräunig, P.; Bremer, J.; Brusa, R. S.; Cabaret, L.; Caccia, M.; Canali, C.; Caravita, R.; Castelli, F.; Cerchiari, G.; Cialdi, S.; Comparat, D.; Consolati, G.; Derking, H.; Di Domizio, S.; Di Noto, L.; Doser, M.; Dudarev, A.; Ereditato, A.; Ferragut, R.; Fontana, A.; Genova, P.; Giammarchi, M.; Gligorova, A.; Gninenko, S. N.; Haider, S.; Huse, T.; Jordan, E.; Jørgensen, L. V.; Kaltenbacher, T.; Kawada, J.; Kellerbauer, A.; Kimura, M.; Knecht, A.; Krasnický, D.; Lagomarsino, V.; Lehner, S.; Malbrunot, C.; Mariazzi, S.; Matveev, V. A.; Moia, F.; Nebbia, G.; Nédélec, P.; Oberthaler, M. K.; Pacifico, N.; Petrá?ek, V.; Pistillo, C.; Prelz, F.; Prevedelli, M.; Regenfus, C.; Riccardi, C.; Røhne, O.; Rotondi, A.; Sandaker, H.; Storey, J.; Subieta Vasquez, M. A.; Špa?ek, M.; Testera, G.; Wildmann, E.; Zavatarelli, S.; Zmeskal, J.

    2014-01-01

    For the first time the AEgIS (Antihydrogen Experiment: Gravity, Interferometry, Spectroscopy) experiment will measure the Earth's local gravitational acceleration g on antimatter through the evaluation of the vertical displacement of an antihydrogen horizontal beam. This will be a model independent test of the Weak Equivalence Principle at the base of the general relativity. The initial goal of a g measurement with a relative uncertainty of 1% will be achieved with less than 1000 detected antihydrogens, provided that their vertical position could be determined with a precision of a few micrometers. An emulsion based detector is very suitable for this purpose featuring an intrinsic sub-micrometric spatial resolution. Nevertheless, the AEgIS experiment requires unprecedented operational conditions for this type of detector, namely vacuum environment and very low temperature. An intense R&D activity is presently going on to optimize the detector for the AEgIS experimental requirements with rather encouraging results.

  13. Momentum measurement of secondary particle by multiple coulomb scattering with emulsion cloud chamber in DONuT experiment

    Microsoft Academic Search

    K. Kodama; N. Saoulidou; G. Tzanakos; B. Baller; B. Lundberg; R. Rameika; J. S. Song; C. S. Yoon; S. H. Chung; S. Aoki; T. Hara; C. Erickson; K. Heller; R. Schwienhorst; J. Sielaff; J. Trammell; K. Hoshino; J. Kawada; M. Komatsu; M. Miyanishi; M. Nakamura; T. Nakano; K. Narita; K. Niwa; N. Nonaka; K. Okada; O. Sato; T. Toshito; S. Miyamoto; S. Takahashi; B. D. Park; T. Furukawa; V. Paolone; T. Kafka

    2007-01-01

    We present a method of momentum measurement of charged particles using emulsion data from the DONuT experiment, and report results from the momentum analysis of secondary particles from neutrino interactions. In 578 neutrino interactions, 2338 secondary particles were analyzed and 83.2% of attempted particles were measured by multiple coulomb scattering.

  14. Fish oil–based lipid emulsions in the treatment of parenteral nutrition-associated liver disease: An ongoing positive experience

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We previously reported the beneficial effect of fish oil-based lipid emulsions (FOLEs) as monotherapy in the treatment of parenteral nutrition-associated liver disease (PNALD). In this report, we share our ongoing experience at Texas Children's Hospital, Houston, in the use of FOLE in treatment of P...

  15. Dosimetry of cosmic particles in nuclear emulsions for the apollo 16, 17 and apollo-soyouz-test-project experiments (1972–1975)

    Microsoft Academic Search

    R. Pfohl; R. Kaiser; J. P. Massue; H. Francois

    1977-01-01

    In the Biostack I, II and III experiments flown on the Apollo 16 and 17 and ASTP missions, nuclear emulsion plates have been used for the first time for heavy-ion identification in connection with biological layers. After the calibration step using the heavy ions available at the Bevalac at Berkeley, the nuclear emulsion can give dosimetric results for the heavy

  16. Direct Photon Production in Proton-Nucleus and Nucleus-Nucleus Collisions

    E-print Network

    J. Cepila; J. Nemchik

    2011-06-01

    Prompt photons produced in a hard reaction are not accompanied with any final state interaction, either energy loss or absorption. Therefore, besides the Cronin enhancement at medium transverse momenta pT and small isotopic corrections at larger pT, one should not expect any nuclear effects. However, data from PHENIX experiment exhibit a significant large-pT suppression in central d+Au and Au+Au collisions that cannot be accompanied by coherent phenomena. We demonstrate that such an unexpected result is subject to the energy sharing problem near the kinematic limit and is universally induced by multiple initial state interactions. We describe production of photons in the color dipole approach and find a good agreement with available data in p+p collisions. Besides explanation of large-pT nuclear suppression at RHIC we present for the first time predictions for expected nuclear effects also in the LHC energy range at different rapidities. We include and analyze also a contribution of gluon shadowing as a leading twist shadowing correction modifying nuclear effects at small and medium pT.

  17. Analysis of variances of quasirapidities in collisions of gold nuclei with track-emulsion nuclei

    SciTech Connect

    Gulamov, K. G.; Zhokhova, S. I.; Lugovoi, V. V., E-mail: lugovoi@uzsci.net; Navotny, V. S., E-mail: navotny@uzsci.net; Saidkhanov, N. S.; Chudakov, V. M. [Uzbek Academy of Sciences, Physical-Technical Institute, Fizika-Solntse Research and Production Association (Uzbekistan)

    2012-08-15

    A new method of an analysis of variances was developed for studying n-particle correlations of quasirapidities in nucleus-nucleus collisions for a large constant number n of particles. Formulas that generalize the results of the respective analysis to various values of n were derived. Calculations on the basis of simple models indicate that the method is applicable, at least for n {>=} 100. Quasirapidity correlations statistically significant at a level of 36 standard deviations were discovered in collisions between gold nuclei and track-emulsion nuclei at an energy of 10.6 GeV per nucleon. The experimental data obtained in our present study are contrasted against the theory of nucleus-nucleus collisions.

  18. PREFACE: Hot Quarks 2012: Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions

    NASA Astrophysics Data System (ADS)

    Bleicher, Markus; Caines, Helen; Calderón de la Barca Sanchez, Manuel; Fries, Rainer; Granier de Cassagnac, Raphaël; Hippolyte, Boris; Mischke, André; Mócsy, Ágnes; Petersen, Hannah; Ruan, Lijuan; Salgado, Carlos A.

    2013-09-01

    The 5th edition of the Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions (Hot Quarks 2012) was held in Copamarina, Puerto Rico from 14-20 October 2012. As in previous years, this meeting gathered more than 70 participants in the early years of their scientific careers. This issue contains the proceedings of the workshop. As in the past, the Hot Quarks workshop offered a unique atmosphere for a lively discussion and interpretation of the current measurements from high energy nuclear collisions. Recent results and upgrades at CERN's Large Hadron Collider (LHC) and Brookhaven's Relativistic Heavy Ion Collider (RHIC) were presented. Measurements from the proton-led run at the CERN-LHC were shown for the first time at this meeting. Recent theoretical developments were also extensively discussed, as well as the proposals for future facilities such as the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, the Electron-Ion Collider at Brookhaven, and the LHeC. The conference's goal to provide a platform for young researchers to learn and foster their interactions was successfully met. We wish to thank the sponsors of the Hot Quarks 2012 Conference, who supported the authors of this volume: Brookhaven National Laboratory (USA), European Laboratory for Particle Physics CERN (Switzerland), European Research Council (EU), ExtreMe Matter Institute EMMI (Germany), Helmholtz International Center for FAIR (Germany), IN2P3/CNRS (France) and the European Research Council via grant #259612, Lawrence Berkeley National Laboratory (USA), Lawrence Livermore National Laboratory (USA), Los Alamos National Laboratory (USA), National Science Foundation (USA), and Netherlands Organization for Scientific Research (Netherlands). Marcus BleicherAndré Mischke Goethe-University Frankfurt and HIC4FAIRUtrecht University and Nikhef Amsterdam GermanyThe Netherlands Helen CainesÁgnes Mócsy Yale UniversityPratt Institute and Brookhaven National Laboratory USAUSA Manuel Calderón de la Barca SánchezHannah Petersen UC DavisFIAS USAGermany Rainer J FriesLijuan Ruan Texas A&M UniversityBrookhaven National Laboratory USAUSA Raphaël Granier de CassagnacCarlos A Salgado CNRS-IN2P3 and Ëcole polytechniqueUniversidade de Santiago de Compostela FranceSpain Boris Hippolyte CNRS-IN2P3 and Université de Strasbourg France The PDF also contains the conference poster.

  19. Development of High Sensitivity Nuclear Emulsion and Fine Grained Emulsion

    NASA Astrophysics Data System (ADS)

    Kawahara, H.; Asada, T.; Naka, T.; Naganawa, N.; Kuwabara, K.; Nakamura, M.

    2014-08-01

    Nuclear emulsion is a particle detector having high spacial resolution and angular resolution. It became useful for large statistics experiment thanks to the development of automatic scanning system. In 2010, a facility for emulsion production was introduced and R&D of nuclear emulsion began at Nagoya university. In this paper, we present results of development of the high sensitivity emulsion and fine grained emulsion for dark matter search experiment. Improvement of sensitivity is achieved by raising density of silver halide crystals and doping well-adjusted amount of chemicals. Production of fine grained emulsion was difficult because of unexpected crystal condensation. By mixing polyvinyl alcohol (PVA) to gelatin as a binder, we succeeded in making a stable fine grained emulsion.

  20. Unusual interactions above 100 TeV: A review of cosmic ray experiments with emulsion chambers

    NASA Technical Reports Server (NTRS)

    Yodh, D. B.

    1977-01-01

    A method is given for analyzing the space correlated collection of jets (gamma ray families) with energies greater than 100 TeV in Pb or Fe absorber sampled by photosensitive layers in an emulsion chamber. Events analyzed indicate large multiplicities of particles in the primary hadron-air interaction, and a marked absence of neutral pions.

  1. Pseudorapidity configurations in collisions between gold nuclei and track-emulsion nuclei

    SciTech Connect

    Gulamov, K. G.; Zhokhova, S. I.; Lugovoi, V. V., E-mail: lugovoi@uzsci.net; Navotny, V. S., E-mail: navotny@uzsci.net; Chudakov, V. M. [Uzbek Academy of Sciences, Institute for Physics and Technology, Fizika-Solntse Research and Production Association (Uzbekistan)

    2010-07-15

    A method of parametrically invariant quantities is developed for studying pseudorapidity configurations in nucleus-nucleus collisions involving a large number of secondary particles. In simple models where the spectrum of pseudorapidities depends on three parameters, the shape of the spectrum may differ strongly from the shape of pseudorapidity configurations in individual events. Pseudorapidity configurations in collisions between gold nuclei of energy 10.6 GeV per nucleon and track-emulsion nuclei are contrasted against those in random stars calculated theoretically. An investigation of pseudorapidity configurations in individual events is an efficient method for verifying theoretical models.

  2. Workshop on Cosmic Ray and High Energy Gamma Ray Experiments for the Space Station Era, Louisiana State University, Baton Rouge, October 17-20, 1984, Proceedings

    NASA Technical Reports Server (NTRS)

    Jones, W. V. (editor); Wefel, J. P. (editor)

    1985-01-01

    The potential of the Space Station as a platform for cosmic-ray and high-energy gamma-ray astronomy is discussed in reviews, reports, and specific proposals. Topics examined include antiparticles and electrons, science facilities and new technology, high-energy nuclear interactions, nuclear composition and energy spectra, Space Shuttle experiments, Space Station facilities and detectors, high-energy gamma rays, and gamma-ray facilities and techniques. Consideration is given to universal-baryon-symmetry testing on the scale of galactic clusters, particle studies in a high-inclination orbit, balloon-borne emulsion-chamber results on ultrarelativistic nucleus-nucleus interactions, ionization states of low-energy cosmic rays, a large gamma-ray telescope for point-source studies above 1 GeV, and the possible existence of stable quark matter.

  3. Investigation of gamma-ray families originating from nucleus-nucleus interactions at ultrahigh energies E{sub 0} in excess of 10{sup 16} eV

    SciTech Connect

    Yuldashbaev, T. S.; Nuritdinov, Kh., E-mail: husnudin@uzsci.net [Uzbek Academy of Sciences, Institute for Physics and Technology, Fizika-Solntse Research and Production Association (Uzbekistan)

    2013-12-15

    Various spatial and energy features of gamma-ray families originating from the interactions of primary nuclei of galactic cosmic rays with nuclei of atmospheric atoms (AA interactions) are studied. The mass composition of galactic cosmic rays is analyzed on the basis of data from x-ray emulsion chambers of the Pamir experiment with the aid of a criterion for selecting gamma-ray families originating from AA interactions (A families) at energies E{sub 0} of primary galactic cosmic rays in excess of 10{sup 16} eV. According to the results obtained in this way only the experimental spatial parameters R{sub 1E} and ? differ from their counterparts in the MC0 model.

  4. Abrupt changes in pentobarbital sensitivity in preBötzinger complex region, hypoglossal motor nucleus, nucleus tractus solitarius, and cortex during rat transitional period (P10-P15).

    PubMed

    Turner, Sara M F; Johnson, Stephen M

    2015-02-01

    On postnatal days P10-P15 in rat medulla, neurotransmitter receptor subunit composition shifts toward a more mature phenotype. Since medullary GABAARs regulate cardiorespiratory function, abrupt alterations in GABAergic synaptic inhibition could disrupt homeostasis. We hypothesized that GABAARs on medullary neurons become more resistant to positive allosteric modulation during P10-P15. Medullary and cortical slices from P10 to P20 rats were used to record spontaneous action potentials in pre-Botzinger Complex (preBötC-region), hypoglossal (XII) motor nucleus, nucleus tractus solitarius (NTS), and cortex during exposure to pentobarbital (positive allosteric modulator of GABAARs). On P14, pentobarbital resistance abruptly increased in preBötC-region and decreased in NTS, but these changes in pentobarbital resistance were not present on P15. Pentobarbital resistance decreased in XII motor nucleus during P11-P15 with a nadir at P14. Abrupt changes in pentobarbital resistance indicate changes in GABAergic receptor composition and function that may compensate for potential increased GABAergic inhibition and respiratory depression that occurs during this key developmental transitional period. PMID:25550216

  5. Baryon Number Transfer in Hadron+Nucleus and Nucleus+Nucleus Collisions: A Link between Elementary and Complex Interactions

    E-print Network

    D. Varga

    2003-03-05

    The baryon number transfer is studied in elementary and complex hadronic interactions at the CERN experiment NA49 at the SPS, at 158 AGeV beam energy (\\sqrt{s}=17.2 GeV). A two component picture is proposed, which builds up the net proton distribution from a target and a projectile component. Using pion beam, the projectile component is experimentally determined for p+p and p+A interactions. A similar stopping behaviour of the projectile component is found for p+A and A+A interactions. Based on these observations, the baryon transfer is assumed to provide a common scale of inelasticity in p+p, p+A and A+A interactions. A model-independent way is proposed to predict the pion multiplicity in A+A.

  6. Limiting Fragmentation Behavior of Projectile Helium (Z = 2) Fragments in Nucleus--Nucleus Interactions at 14.6 A GeV

    NASA Astrophysics Data System (ADS)

    Kumar, Ashwini; Singh, Gurmukh; Singh, Bhartendu K.

    2012-12-01

    An analysis of projectile helium (Z = 2) fragments based on 855 minimum-bias inelastic events induced by 14.6 A GeV 28Si beam in a nuclear emulsion is presented in order to test the hypothesis of limiting fragmentation. The projected angular distributions of projectile helium fragments have been fitted with Gaussian curves in individual helium reaction channels and also in different emulsion target events. Furthermore, average emission angle of projectile helium fragments has been studied in individual helium reaction channels with different emulsion target groups. On the basis of pseudo-rapidity distribution, an energy independent limiting fragmentation behavior of projectile helium fragments is also investigated in the fragmentation region.

  7. Charm studies in emulsion

    E-print Network

    Kalinin, Sergey

    Neutrino-nucleon scattering is an effective way to investigate the inner structure of the nucleon, to extract the Standard Model parameters and to explore heavy quarks production dynamics. In the last decades, several experiments have been constructed to study weak interactions of neutrinos with nucleons. One of them was CERN-WA95 experiment operated by the CHORUS collaboration. It is based on a hybrid detector with nuclear emulsion as a target followed by electronic devices. Nuclear emulsion provides three dimensional spatial information with an outstanding resolution of the order of one micron. Therefore, it is ideal to detect short-lived particles. A special technique has been developed to reconstruct events in the emulsion which allows to perform a detailed investigation of events such as charmed hadrons production by neutrinos. As a result, the backround in the selected charm sample is up to six times lower compared to similar experiments. Such a method also permits to make direct measurements of some qu...

  8. Rheology of Attractive Emulsions

    E-print Network

    Sujit S. Datta; Dustin D. Gerrard; Travers S. Rhodes; Thomas G. Mason; David A. Weitz

    2012-01-12

    We show how attractive interactions dramatically influence emulsion rheology. Unlike the repulsive case, attractive emulsions below random close packing, RCP, can form soft gel-like elastic solids. However, above RCP, attractive and repulsive emulsions have similar elasticities. Such compressed attractive emulsions undergo an additional shear-driven relaxation process during yielding. Our results suggest that attractive emulsions begin to yield at weak points through the breakage of bonds, and, above RCP, also undergo droplet configurational rearrangements.

  9. Results from NA60 experiment at the CERN SPS

    SciTech Connect

    Usai, G.; Cicalo, C.; De Falco, A.; Floris, M.; Masoni, A.; Puddu, G.; Serci, S. [Univ. di Cagliari, Cagliari (Italy); INFN, Cagliari (Italy); Arnaldi, R.; Colla, A.; Cortese, P.; Ferretti, A.; Oppedisano, C. [Univ. di Torino (Italy) and INFN (Italy); Averbeck, R.; Drees, A. [SUNY Stony Brook, New York (United States); Banicz, K. [CERN, Geneva (Switzerland); Univ. Heidelberg, Heidelberg (Germany); Castor, J.; Devaux, A.; Force, P.; Manso, F. [LPC, Univ. Blaise Pascal, Clermont-Ferrand (France); CNRS-IN2P3, Clermont-Ferrand (France); Chaurand, B. [LLR, Ecole Polytechnique, Palaiseau (France); CNRS-IN2P3, Palaiseau (France)] (and others)

    2006-07-11

    The NA60 experiment studies open charm and prompt dimuon production in proton-nucleus and nucleus-nucleus collisions at the CERN SPS. During 2003 the experiment collected data in Indium-Indium collisions at 158 GeV per nucleon. In this paper the first results on low mass dimuons, intermediate mass dimuons and J/{psi} suppression are presented.

  10. Emulsions Droplet Capture Mechanism in Porous Media

    NASA Astrophysics Data System (ADS)

    Zeidani, Khalil; Polikar, Marcel

    2006-03-01

    This study was undertaken to investigate the physics of emulsion flow in porous media. The objective of experiments were to study the applicability of oil-in-water emulsion as a plugging agent in the vicinity of the well bore for thousands of Canadian gas wells that are continuously leaking gas to surface. The motion of oil droplets and the capture mechanisms were investigated through visualized experiments. Well-characterized emulsions were injected into a micro model resembling a two parallel plate model packed with glass beads. Effects of emulsion properties and wettability of the medium were studied on a plugging mechanism. The results demonstrate the reduction in permeability mainly due to droplets size exclusion compared to the pore constrictions. Also, smaller droplets may lodge and coalesce in pores crevices thereby accelerating the blockage process. Moreover, more viscous emulsions are more effective compared with the less viscous ones due to combined effects of capillary and viscous forces. The deposition of droplets was adjusted through utilizing different preflush solutions. Criteria were set for enhancing emulsion penetration depth thereby defining the extent of the blocked region. In conclusion, this work characterizes the physics of emulsion flow in porous media and demonstrates its application as a novel sealant in near well bore region. The novelty, which constitutes a step-change in technology, is a method that emplaces an emulsion at a desired location in underground media.

  11. Electrochemistry of a single attoliter emulsion droplet in collisions.

    PubMed

    Kim, Byung-Kwon; Kim, Jiyeon; Bard, Allen J

    2015-02-18

    We report here the electrochemistry of emulsion droplets by observing single emulsion droplet collisions with selective electrochemical reduction on an ultramicroelectrode (UME). With appropriately applied potentials at an UME, we can observe the electrochemical effects of single collision signals from the complete electrolysis of single emulsion droplets, or selective electrolysis of redox species in single emulsion droplets. This was observed with nitrobenzene (NB), 7,7,8,8-tetracyanoquinodimethane (TCNQ), and ionic liquid. The NB, TCNQ, and ionic liquid act as emulsion material, redox specie, and emulsifier (and electrolyte), respectively. NB emulsions and NB (TCNQ) emulsions were made by ultrasonic processing. During the amperometric current-time (i-t) curve measurement with NB/water emulsion at -0.65 V, reduction of NB emulsion droplets was measured. In the case of less negative potentials, e.g., at -0.45 V with a NB (TCNQ) emulsion, selective reduction of TCNQ in NB droplet was measured. Spike-like responses from electrolysis of NB or TCNQ in each experiment were observed. From these single-particle collision results of NB and NB (TCNQ) emulsions, the collision frequency, size distribution, i-t decay behavior of emulsion droplets, and possible mechanisms are discussed. PMID:25616104

  12. Characteristics of alpha projectile fragments emission in interaction of nuclei with emulsion

    E-print Network

    M. K. Singh; Ramji Pathak; V. Singh

    2010-08-12

    The properties of the relativistic alpha fragments produced in interactions of 84^Kr at around 1 A GeV in nuclear emulsion are investigated. The experimental results are compared with the similar results obtained from various projectiles with emulsion interactions at different energies. The total, partial nuclear cross-sections and production rates of alpha fragmentation channels in relativistic nucleus-nucleus collisions and their dependence on the mass number and initial energy of the incident projectile nucleus are investigated. The yields of multiple alpha fragments emitted from the interactions of projectile nuclei with the nuclei of light, medium and heavy target groups of emulsion-detector are discussed and they indicate that the projectile-breakup mechanism seems to be free from the target mass number. It is found that the multiplicity distributions of alpha fragments are well described by the Koba-Nielsen-Olesen (KNO) scaling presentation. The mean multiplicities of the freshly produced newly created charged secondary particles, normally known as shower and secondary particles associated with target in the events where the emission of alpha fragments were accompanied by heavy projectile fragments having Z value larger than 4 seem to be constant as the alpha fragments multiplicity increases, and exhibit a behavior independent of the alpha fragments multiplicity.

  13. Multiple emulsions High-Order Multiple Emulsions Formed in

    E-print Network

    Multiple emulsions High-Order Multiple Emulsions Formed in Poly(dimethylsiloxane) Microfluidics** A. R. Abate and D. A. Weitz* Multiple emulsions are nested sets of drops.[1,2] Drops of one kind of yet another fluid. Such ``emulsions within emulsions'' are very useful for many applications

  14. Emulsion Droplet Combustion in Microgravity: Water/Heptane Emulsions

    NASA Technical Reports Server (NTRS)

    Avedisian, C. Thomas

    1997-01-01

    This presentation reviews a series of experiments to further examine parametric effects on sooting processes of droplet flames in microgravity. The particular focus is on a fuel droplet emulsified with water, specifically emulsions of n-heptane as the fuel-phase and water as the dispersed phase. Water was selected as the additive because of its anticipated effect on soot formation, and the heptane fuel phase was chosen to theoretically reduce the likelihood of microexplosions because its boiling point is nearly the same as that of water: 100 C for water and 98 C for heptane. The water content was varied while the initial droplet diameter was kept within a small range. The experiments were carried out in microgravity to reduce the effects of buoyancy and to promote spherical symmetry in the burning process. Spherically symmetric droplet burning is a convenient starting point for analysis, but experimental data are difficult to obtain for this situation as evidenced by the fact that no quantitative data have been reported on unsupported emulsion droplet combustion in a convection-free environment. The present study improves upon past work carried out on emulsion droplet combustion in microgravity which employed emulsion droplets suspended from a fiber. The fiber can be instrusive to the emulsion droplet burning process as it can promote coalescence of the dispersed water phase and heterogeneous nucleation on the fiber. Prior work has shown that the presence of water in liquid hydrocarbons can have both beneficial and detrimental effects on the combustion process. Water is known to reduce soot formation and radiation heat transfer to combustor walls Gollahalli (1979) reduce flame temperatures and thereby NOx emissions, and encourage secondary droplet atomization or microexplosion. Water also tends to retard ignition and and promote early extinction. The former effect restricted the range of water volume fractions as discussed below.

  15. An instrument employing electronic counters and an emulsion chamber for studying heavy cosmic ray interactions (JACEE-3)

    NASA Technical Reports Server (NTRS)

    Austin, R. W.; Meegan, C. A.; Parnell, T. A.; Selig, W. J.; Watts, J. W.; Burnett, T. H.; Iwai, J.; Lord, J. J.; Strauscz, S.; Wilkes, R. J.; Jones, W. V.

    1983-01-01

    A JACEE-3 instrument was flown on a balloon in June 1982 for 6.1 sq m sr hr exposure at an average atmospheric depth of 5 gm/sq cm in order to study the cosmic ray spectra, composition, and interactions above 1 TeV. The nucleus-nucleus interactions were studied above 20 GeV/amu from z = 6 to z = 26. The electronic counters contained gas Cerenkov structures with a 1.0-cm thick lead glass and a 1.27-cm thick Teflon radiator. A comparison to the instrument prototype is made. Based on the electronic counter event data, the finding efficiency of the hodoscope is noted to be near 100 percent for z greater than or equal to 22. A comparison is made between the hodoscope-predicted position and track found at P3 in an emulsion chamber.

  16. Resonant ultrasonic attenuation in emulsions

    NASA Astrophysics Data System (ADS)

    Brunet, Thomas; Mascaro, Benoit; Poncelet, Olivier; Aristégui, Christophe; Raffy, Simon; Mondain-Monval, Olivier; Leng, Jacques

    2013-08-01

    We report the achievement of scattering resonant emulsions devoted to the frequency-control of acoustic attenuation in the megahertz range. By means of robotics, we produced highly monodisperse, in both size and shape, fluorinated-oil droplet suspensions, providing experimental evidence of several Mie scattering resonances. Ultrasonic experiments performed in such complex media are compared, with an excellent quantitative agreement, to theoretical predictions derived within the framework of the independent scattering approximation.

  17. Fat Emulsions for Injection

    MedlinePLUS

    Your doctor has ordered fat emulsion to be used as a source of calories and fatty acids to maintain or increase your weight. The medication will be ... Before you administer fat emulsion, look at the solution closely. It should be free of floating material. Gently squeeze the bag or observe the solution ...

  18. Fluctuations in transverse energy and mulitplicity, energy densities, and neutral pion spectra in nucleus-nucleus collisions at 200 GeV/nucleon

    SciTech Connect

    Not Available

    1989-01-01

    The main goal of the CERN heavy-ion experiments is the search for an indication that the predicted state of deconfined quarks and gluons, the quark-gluon plasma (QGP), has been produced. The quantity most crucial to the probability of QGP formation is the thermalized energy density attained during the heavy-ion reaction. The amount of energy radiated transverse to the beam direction is the experimental quantity which is believed to be a measure of the amount of energy deposition in the reaction, and hence to reflect the energy density attained. In this presentation we consider the systematics of transverse energy production at CERN SPS energies, and we use the results to make estimates, under various assumptions, of attained energy densities.

  19. Heavy quark studies with nuclear emulsions

    E-print Network

    G. De Lellis; P. Migliozzi; P. Strolin

    2003-01-23

    Emulsions have started particle physics with the discovery of natural radioactivity by Becquerel in 1896. The development of the ``nuclear emulsions'' made it possible to detect tracks of single particle and to perform detailed measurements of their interactions. The discovery of the pion in 1947 was the first, spectacular demonstration of their unique features for the direct observation of the production and decay of short-lived particles, with negligible or very low background. In particular, these features are now exploited for studies of heavy quark physics in experiments where nuclear emulsions are combined with electronic detectors and profit is taken of the remarkable technological progress in automated analysis. In these experiments, neutrinos provide a selective probe for specific quark flavors. Interesting results on charm production and decay are expected in the very near future.

  20. Topical delivery of acetyl hexapeptide-8 from different emulsions: influence of emulsion composition and internal structure.

    PubMed

    Hoppel, Magdalena; Reznicek, Gottfried; Kählig, Hanspeter; Kotisch, Harald; Resch, Günter P; Valenta, Claudia

    2015-02-20

    Acetyl hexapeptide-8 (AH-8) is a well-known component of anti-aging products and was recently explored as a promising topical treatment of blepharospasm. Although AH-8 appears in a variety of cosmetic products, its skin penetration is sparsely studied and controversially discussed. Therefore, the aim of the present study was to investigate the influence of the vehicle type on the AH-8 delivery to the skin. Besides skin permeation experiments with Franz type diffusion cells, the spatial distribution of AH-8 in the stratum corneum after a real in-use application was investigated by in vitro tape stripping on porcine ear skin. By applying LC-MS/MS for quantification of AH-8, we demonstrated that a multiple water-in-oil-in-water (W/O/W) emulsion can significantly increase penetration of AH-8 into porcine skin compared to simple O/W and W/O emulsions. The internal structure of the developed multiple emulsion was confirmed by electron microscopic investigations and NMR self diffusion studies. In general, a clear superiority of water-rich W/O/W and O/W emulsions over an oil-rich W/O emulsion in terms of dermal delivery of AH-8 was found. This enhanced delivery of AH-8 could be explained by an increased absorption of the water-rich emulsions into the skin, confirmed by combined ATR-FTIR and tape stripping experiments. PMID:25497319

  1. Semiclassical and microscopic calculations of the spin-orbit density part of the Skyrme nucleus-nucleus interaction potential with temperature effects included

    SciTech Connect

    Gupta, Raj K.; Singh, Dalip [Department of Physics, Panjab University, Chandigarh-160014 (India); Frankfurt Institute for Advanced Studies (FIAS), Johann Wolfgang Goethe-Universitaet, Max-von-Laue-Str. 1, D-60438 Frankfurt am Main (Germany); Greiner, Walter [Frankfurt Institute for Advanced Studies (FIAS), Johann Wolfgang Goethe-Universitaet, Max-von-Laue-Str. 1, D-60438 Frankfurt am Main (Germany)

    2007-02-15

    The semiclassical formulation of the Skyrme energy density functional for spin-orbit density part of the interaction potential is compared with the microscopic shell model formulation, at both the ground state and finite temperatures. The semiclassical spin-orbit interaction potential is shown to contain exactly the same shell effects as are there in the microscopic shell model, provided a normalization of all semiclassical results to the spin-saturated case (for one or both nuclei as spin-saturated) is made. On the other hand, the {alpha} nucleus structure present in microscopic shell model is found absent in semiclassical approach. The role of temperature is found not to change the behavior of shell or {alpha} nucleus structure effects up to about 3 MeV, and increase or decrease the height of the (normalized) barriers in accordance with the shell structure of nuclei. Calculations are made for three two-nucleon transfer reactions forming the {alpha}-nucleus A=4n,N=Z compound systems {sup 56}Ni{sup *} and {sup 48}Cr{sup *} and the non-{alpha}-nucleus compound system {sup 52}Cr{sup *}, and for Skyrme forces SIII and SLy4. The two parameter Fermi density, with its parameters fitted to experiments and made temperature dependent in a model way, is used for the nuclear density in semiclassical calculations, and the same in microscopic shell model is achieved via the Fermi-Dirac occupation of shell model states and particle number conservation.

  2. Magnetoresistive emulsion analyzer.

    PubMed

    Lin, Gungun; Baraban, Larysa; Han, Luyang; Karnaushenko, Daniil; Makarov, Denys; Cuniberti, Gianaurelio; Schmidt, Oliver G

    2013-01-01

    We realize a magnetoresistive emulsion analyzer capable of detection, multiparametric analysis and sorting of ferrofluid-containing nanoliter-droplets. The operation of the device in a cytometric mode provides high throughput and quantitative information about the dimensions and magnetic content of the emulsion. Our method offers important complementarity to conventional optical approaches involving ferrofluids, and paves the way to the development of novel compact tools for diagnostics and nanomedicine including drug design and screening. PMID:23989504

  3. Magnetoresistive Emulsion Analyzer

    PubMed Central

    Lin, Gungun; Baraban, Larysa; Han, Luyang; Karnaushenko, Daniil; Makarov, Denys; Cuniberti, Gianaurelio; Schmidt, Oliver G.

    2013-01-01

    We realize a magnetoresistive emulsion analyzer capable of detection, multiparametric analysis and sorting of ferrofluid-containing nanoliter-droplets. The operation of the device in a cytometric mode provides high throughput and quantitative information about the dimensions and magnetic content of the emulsion. Our method offers important complementarity to conventional optical approaches involving ferrofluids, and paves the way to the development of novel compact tools for diagnostics and nanomedicine including drug design and screening. PMID:23989504

  4. Isotachophoresis with emulsions

    PubMed Central

    Goet, G.; Baier, T.; Hardt, S.; Sen, A. K.

    2013-01-01

    An experimental study on isotachophoresis (ITP) in which an emulsion is used as leading electrolyte (LE) is reported. The study aims at giving an overview about the transport and flow phenomena occurring in that context. Generally, it is observed that the oil droplets initially dispersed in the LE are collected at the ITP transition zone and advected along with it. The detailed behavior at the transition zone depends on whether or not surfactants (polyvinylpyrrolidon, PVP) are added to the electrolytes. In a system without surfactants, coalescence is observed between the droplets collected at the ITP transition zone. After having achieved a certain size, the droplets merge with the channel walls, leaving an oil film behind. In systems with PVP, coalescence is largely suppressed and no merging of droplets with the channel walls is observed. Instead, at the ITP transition zone, a droplet agglomerate of increasing size is formed. In the initial stages of the ITP experiments, two counter rotating vortices are formed inside the terminating electrolyte. The vortex formation is qualitatively explained based on a hydrodynamic instability triggered by fluctuations of the number density of oil droplets. PMID:24404037

  5. How does oil type determine emulsion characteristics in concentrated Na-caseinate emulsions?

    PubMed

    Tan, Hui Lin; McGrath, Kathryn M

    2013-08-01

    Macroscopic properties and ensemble average diffusion of concentrated (dispersed phase 50-60 wt%) Na-caseinate-stabilised emulsions for three different oils (soybean oil, palm olein and tetradecane) were explored. On a volume fraction basis, pulsed gradient stimulated echo (PGSTE)-NMR data show that droplet dynamics for all three systems are similar within a region of the emulsion morphology diagram. The exact limits of the emulsion space depend however on which oil is considered. The reduced solubility of tetradecane in water, and Na-caseinate in tetradecane, result in the stabilisation of flocs during formulation. Floc formation is not observed when soybean oil or palm olein is used under identical emulsion formulation conditions. Linear rheology experiments provide indirect evidence that the local structure and the properties of the thin film interfacial domain of tetradecane emulsions vary from those of soybean oil and palm olein emulsions. Collectively these data indicate that protein/oil interactions within a system dominate over specific oil droplet structure and size distribution, which are similar in the three systems. PMID:23683496

  6. Emulsions for interfacial filtration.

    SciTech Connect

    Grillet, Anne Mary; Bourdon, Christopher Jay; Souza, Caroline Ann; Welk, Margaret Ellen; Hartenberger, Joel David; Brooks, Carlton, F.

    2006-11-01

    We have investigated a novel emulsion interfacial filter that is applicable for a wide range of materials, from nano-particles to cells and bacteria. This technology uses the interface between the two immiscible phases as the active surface area for adsorption of targeted materials. We showed that emulsion interfaces can effectively collect and trap materials from aqueous solution. We tested two aqueous systems, a bovine serum albumin (BSA) solution and coal bed methane produced water (CBMPW). Using a pendant drop technique to monitor the interfacial tension, we demonstrated that materials in both samples were adsorbed to the liquid-liquid interface, and did not readily desorb. A prototype system was built to test the emulsion interfacial filter concept. For the BSA system, a protein assay showed a progressive decrease in the residual BSA concentration as the sample was processed. Based on the initial prototype operation, we propose an improved system design.

  7. Emulsions from Aerosol Sprays

    PubMed

    Hengelmolen; Vincent; Hassall

    1997-12-01

    An electrostatic emulsification apparatus has been designed for the purpose of studying diffusion from oil droplets which have a mean size in the range of approximately 1.5-3.5 &mgr;m, with standard deviations of 40-50%. The emulsification technique involves the collection of a spray of electrically charged oil droplets onto a rotating water film which is sustained from a reservoir. In this way, emulsions with volume fractions of approximately 10(-3) are produced within several minutes at oil flow rates of around 10(-2) ml min-1. Phase-Doppler anemometry (PDA) was used to assess droplet size distributions for the sprays and emulsions. Results show that the mean emulsion droplet size was smaller than the mean spray droplet size by several orders of magnitude. At flow rates around 10(-2) ml min-1, the spray droplet size distribution was little affected by the applied potential between about -4.20 and -4.65 kV (mean droplet size between approximately 7.6 and 7.8 &mgr;m, with standard deviations of approximately 20%), whereas the mean droplet size of the corresponding emulsion decreased more rapidly with applied potential. Above an applied potential of approximately -4.30 kV, which corresponded to an emulsion droplet size below approximately 2 &mgr;m, the measured volume fraction of the emulsion decreased with respect to the volume fraction as calculated on the basis of total amount of injected oil. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID:9441645

  8. Preparation and stabilization of D-limonene Pickering emulsions by cellulose nanocrystals.

    PubMed

    Wen, Chunxia; Yuan, Qipeng; Liang, Hao; Vriesekoop, Frank

    2014-11-01

    The aim of this study was to investigate D-limonene Pickering emulsion stabilized by cellulose nanocrystals (CNCs) and factors that may affect its properties. CNCs were prepared by ammonium persulfate hydrolysis of corncob cellulose, and D-limonene Pickering emulsions were generated by ultrasonic homogenizing method. The morphology and size of the prepared emulsions with different CNCs concentrations were studied by optical microscopy and laser light diffraction. In addition, factors that may affect the stability of emulsions such as ionic concentration, pH and temperature were also studied. As indicated by the experiment data, when temperature rose, the stability to of emulsions would be increased, and the stability of emulsions was reduced with low pH or high salt concentration due to electrostatic screening of the negatively charged CNC particles. In conclusion, high stability of D-limonene Pickering emulsions could be obtained by CNCs. PMID:25129799

  9. Detecting Double Beta Decays Using Nuclear Emulsions

    E-print Network

    Marcos Dracos

    2008-05-20

    Neutrino nature and absolute mass scale are major questions in particle physics which cannot be addressed by the present neutrino oscillation program. To answer these two questions, several neutrinoless double beta decay experiments are underway or planed for the near future. These experiments, mainly use bolometric techniques or gaseous counters coupled with scintillator detectors. The energy resolution is better in bolometric experiments but experiments coupling tracking with calorimetry have the advantage of observing the two electron tracks and remove many background sources. Here, we present a proposal of using nuclear emulsions to observe double beta decays. This technique has the advantage of precise tracking and vertexing even for low energy electrons.

  10. On formulating ophthalmic emulsions.

    PubMed

    Mafi, Roozbeh; Gray, Cameron; Pelton, Robert; Ketelson, Howard; Davis, James

    2014-10-01

    The formulation of dilute, transparent ophthalmic emulsions (eye drops) with long shelf lives is a challenge because of the tendency of the emulsion droplets to aggregate, particularly in the presence of the water-soluble polymers typically used in eye drops. While many functions of eye drops, such as lubricity and residence time in the eye, are promoted by high concentrations of high molecular weight water-soluble polymers, emulsified lipids and drugs aggregate in the eye drop bottle if the polymer concentration is above the critical flocculation concentration (CFC). The purpose is to develop a simple approach to predict the CFC for polymers based on information readily available in the literature. High molecular weight guar was hydrolyzed to give a series of guar samples spanning a wide range of average molecular weights. The CFC values and critical viscosity concentrations were measured as functions guar properties, using electrophoresis, dynamic light scattering and rheology measurements. The higher the guar molecular weight, the lower was the CFC, the maximum concentration that can be tolerated in the eye drop formulation. The guar CFC values were approximately equal to the overlap concentrations where guar molecules start to overlap in solution. We propose that the CFC can be estimated for any water-soluble polymer using the polymer molecular weight and the readily available Mark-Houwink parameters, thus providing a design rule for ophthalmic emulsions. PMID:25016540

  11. Showing Emulsion Properties with Common Dairy Foods

    NASA Astrophysics Data System (ADS)

    Bravo-Diaz, Carlos; Gonzalez-Romero, Elisa

    1996-09-01

    Foods are mixtures of different chemical compounds, and the quality we sense (taste, texture, color, etc.) are all manifestations of its chemical properties. Some of them can be visualized with the aid of simple, safe and inexpensive experiments using dairy products that can be found in any kitchen and using almost exclusively kitchen utensils. In this paper we propose some of them related with food emulsions. Food emulsions cover an extremely wide area of daily-life applications such as milk, sauces, dressings and beverages. Experimentation with some culinary recipes to prepare them and the analyisis of the observed results is close to ideal subject for the introduction of chemical principles, allowing to discuss about the nature and composition of foods, the effects of additives, etc. At the same time it allows to get insights into the scientific reasons that underlie on the recipes (something that it is not usually found in most cookbooks). For example, when making an emulsion like mayonnaise, why the egg yolks and water are the first materials in the bowl , and the oil is added to them rather than in the other way around? How you can "rescue" separate emulsions (mayonnaise)? Which parameters affect emulsion stability? Since safety, in its broad sense, is the first requisite for any food, concerns about food exist throughout the world and the more we are aware of our everyday life, the more likely we will be to deal productively with the consequences. On the other hand, understanding what foods are and how cooking works destroys no delightful mystery of the art of cuisine, instead the mystery expands.

  12. Experimental feature in the primary-proton flux at energies above 10 TeV according to the results of searches for primary particles in nuclear emulsions exposed in the stratosphere (RUNJOB Experiment)

    SciTech Connect

    Zayarnaya, I. S. [Russian Academy of Sciences, Lebedev Institute of Physics (Russian Federation)

    2008-02-15

    In the RUNJOB experiment, a long-term exposure of x-ray emulsion chambers in the stratosphere from 1995 to 1999 with the aim of studying the composition and spectra of primary cosmic particles in the energy range 10-1000 TeV per nucleon revealed about 50% proton tracks. The remaining events of the proton group did not feature any candidate for a track of a singly charged particle within the search region determined from measurements of the coordinates of background nuclei going close to the sought track. Methodological factors that could explain this experimental observation are considered. A possible physical reason associated with the presence of a neutral component in the flux of primary protons in the energy region above 10 TeV is also analyzed.

  13. Particle-stabilized emulsions comprised of solid droplets.

    PubMed

    Giermanska-Kahn, J; Laine, V; Arditty, S; Schmitt, V; Leal-Calderon, F

    2005-05-10

    We kinetically stabilize oil-in-water emulsions comprising paraffin crystals by adsorbing solid particles (silica) of colloidal size at the oil/water interface. We obtain a set of emulsions that are quiescently stable for a long period of time (months), while the same emulsions are destabilized after only a few hours in the presence of surfactant molecules alone. The emulsions are submitted to a shear stress in order to probe their stability under flow conditions. Partial coalescence and gelation occur when the shear is applied for a sufficiently long period of time. The experiments reveal the existence of a critical droplet mass fraction, phi*, that defines a sharp transition between slow and fast gelation. The process of gelation is rather slow for phi < phi*, occurring at the scale of hours, and becomes almost instantaneous above phi*. PMID:16032841

  14. Differential scanning calorimetry characterization of water-in-oil emulsions from Mexican crude oils

    Microsoft Academic Search

    Javier A. Díaz-Ponce; Eugenio A. Flores; Alfonso Lopez-Ortega; Jose G. Hernández-Cortez; Arquimides Estrada; Laura V. Castro; Flavio Vazquez

    2010-01-01

    A simplified equation relating water droplet size distribution to crystallization temperature, determined from differential\\u000a scanning calorimetry (DSC) curves of aqueous emulsions of petroleum is reported in this article. A series of water-in-oil\\u000a (W\\/O) emulsions was prepared by dispersion of water in different Mexican crude oils; in a classical DSC experiment, these\\u000a emulsions were submitted to a regular heating and cooling

  15. Detection and analysis of tau–neutrino interactions in DONUT emulsion target

    Microsoft Academic Search

    K. Kodama; N. Saoulidou; G. Tzanakos; B. Baller; B. Lundberg; R. Rameika; J. S Song; C. S Yoon; S. H Chung; S. Aoki; T. Hara; C. Erickson; K. Heller; R. Schwienhorst; J. Sielaff; J. Trammell; K. Hoshino; H. Jiko; J. Kawada; T. Kawai; M. Komatsu; H. Matsuoka; M. Miyanishi; M. Nakamura; T. Nakano; K. Narita; K. Niwa; N. Nonaka; K. Okada; O. Sato; T. Toshito; V. Paolone; T. Kafka

    2002-01-01

    The DONUT experiment used an emulsion\\/counter-hybrid-detector, which succeeded in detecting tau–neutrino charged-current interactions. A new method of emulsion analysis, NETSCAN, was used to locate neutrino events and detect tau decays. It is based on a fully automated emulsion readout system (Ultra Track Selector) developed at Nagoya University.The achieved plate-to-plate alignment accuracy of ?0.2?m over an area of 2.6mm×2.6mm permitted an

  16. Cyclodextrin stabilised emulsions and cyclodextrinosomes.

    PubMed

    Mathapa, Baghali G; Paunov, Vesselin N

    2013-11-01

    We report the preparation of o/w emulsions stabilised by microcrystals of cyclodextrin-oil inclusion complexes. The inclusion complexes are formed by threading cyclodextrins from the aqueous phase on n-tetradecane or silicone oil molecules from the emulsion drop surface which grow further into microrods and microplatelets depending on the type of cyclodextrin (CD) used. These microcrystals remain attached on the surface of the emulsion drops and form densely packed layers which resemble Pickering emulsions. The novelty of this emulsion stabilisation mechanism is that molecularly dissolved cyclodextrin from the continuous aqueous phase is assembled into colloid particles directly onto the emulsion drop surface, i.e. molecular adsorption leads to effective Pickering stabilisation. The ?-CD stabilised tetradecane-in-water emulsions were so stable that we used this system as a template for preparation of cyclodextrinosomes. These structures were produced solely through formation of cyclodextrin-oil inclusion complexes and their assembly into a crystalline phase on the drop surface retained its stability after the removal of the core oil. The structures of CD-stabilised tetradecane-in-water emulsions were characterised using optical microscopy, fluorescence microscopy, cross-polarised light microscopy and WETSEM while the cyclodextrinosomes were characterised by SEM. We also report the preparation of CD-stabilised emulsions with a range of other oils, including tricaprylin, silicone oil, isopropyl myristate and sunflower oil. We studied the effect of the salt concentration in the aqueous phase, the type of CD and the oil volume fraction on the type of emulsion formed. The CD-stabilised emulsions can be applied in a range of surfactant-free formulations with possible applications in cosmetics, home and personal care. Cyclodextrinosomes could find applications in pharmaceutical formulations as microencapsulation and drug delivery vehicles. PMID:24043288

  17. 8. Particle detectors 8.1 Emulsions

    E-print Network

    Pohl, Martin Karl Wilhelm

    8. Particle detectors 8.1 Emulsions Nuclear emulsions can be used to give 3-dimensional information on the tracks that energetic particles leave behind. In contrast to ordinary photographic emulsion, the nuclear emulsions are sensitive to the low-energy electrons liberated by the ionization induced by an energetic

  18. Dehydration Efficiency of Water-in-Crude Oil Emulsions in Alternating Current Electrical Fields

    Microsoft Academic Search

    Simone Less; Andreas Hannisdal; Johan Sjöblom

    2010-01-01

    The influence of several operational variables on the electrostatic separation of water-in-crude oil emulsions is investigated in a concentric cylinder rheometer equipped with an alternating current (AC) generator. Shear rate, temperature, emulsion water content, electric field strength, and application time are all found to play a role in the process. The droplet size distributions achieved across some of the experiments

  19. The Preparation and Testing of a Common Emulsion and Personal Care Product: Lotion

    ERIC Educational Resources Information Center

    Mabrouk, Suzanne T.

    2004-01-01

    A chemical analysis of lotions, which comprises of categorizations of moisturizers and emulsions, with the preparation and testing of three lotions, is done. The experiment piques students' interest in preparing lotions and emulsions, and proves the value of chemistry in satisfying the needs of everyday life.

  20. Experimental investigation on diesel engine with diestrol–water micro emulsions

    Microsoft Academic Search

    G. R. Kannan; R. Anand

    2011-01-01

    Experiments were conducted on a single cylinder direct injection diesel engine using diesel, biodiesel and biodiesel–diesel–ethanol (diestrol) water micro emulsion fuels to investigate the performance, emission and combustion characteristics of the engine under different load conditions at a constant speed of 1500 rpm. The results indicated that biodiesel and micro emulsion fuels had a higher brake specific fuel consumption (BSFC) than

  1. On the Origin of Stratification in Creaming Emulsions Daniel M. Mueth, John C. Crocker, Sergei E. Esipov, and David G. Grier

    E-print Network

    Grier, David

    On the Origin of Stratification in Creaming Emulsions Daniel M. Mueth, John C. Crocker, Sergei E], and the generation of a se­ quence of Burgers shocks [11]. We describe experiments on creaming emulsions which of suspended particles and the horizontal thermal gradient. The decane­in­water emulsions used in this study

  2. Guidelines for Processing Emulsion-Based Foods

    Microsoft Academic Search

    Ganesan Narsimhan; Zebin Wang

    Emulsions are dispersions of one liquid into the second immiscible liquid in the form of fine droplets. Emulsions can be classified\\u000a as either oil-in-water or water-inoil emulsions depending on whether oil or water is the dispersed phase. Milk, cream and\\u000a sauces are some examples of oil-in-water emulsions whereas butter and margarine are examples of water-in-oil emulsions. Ice\\u000a cream and fabricated

  3. Microgravity as a tool for studies on emulsion stability

    NASA Astrophysics Data System (ADS)

    Liggieri, Libero; Ferrari, Michele; Passerone, Alberto; Ravera, Francesca; Loglio, Giuseppe; Pandolfini, Piero; Steinchen, Annie; Antoni, Michael; Sanfeld, Albert; Miller, Reinhard; Fainerman, Valentin B.; Grigoriev, Dmitri O.; Kovalchuk, Vladimir I.; Krägel, Jürgen; Makievski, Alexander V.; Clausse, Danièle; Komunjer, Ljepsa; Gomez, F.; Noik, Christine; Dalmazzone, Christine; di Lullo, Alberto; del Gaudio, Lucilla; Leser, Martin E.; Michel, Martin

    2005-10-01

    The definition of methodologies for the stabilisation or destabilisation of liquid disperse systems, such as foams and emulsions, is an important scientific and technological goal, with spin-offs for a vast number of technologies, processes and products. Progresses in this area require intensive investigation and modelling of the processes occurring on different timescales and dimensions: the physical chemistry of liquid interfaces and films, droplet interaction and internal dynamics of the emulsion. Through the damping of convection and the suppression of buoyancy, microgravity conditions provide unique opportunities for studies: a purely diffusive environment for the investigation of transport and adsorption of surface active molecules and the possibility of studying droplet coalescence and aggregation processes decoupled from sedimentation or creaming. The fundamental and Applied Studies in Emulsion Stability (FASES) MAP project was set up to study the links between the properties of droplet interfaces and films, and the basic mechanisms (aggregation and coalescence) involved in the destabilisation of emulsions. Key microgravity experiments will provide data and/or tests of the developed models, in conjunction with extensive ground investigations. To this end, two International Space Station facilities are under development: Facility for Adsorption and Surface Tension study (FASTER) to investigate the physical chemistry of the single interfaces and liquid-liquid films, and the FASES Experiment Container for the Fluid Science Laboratory to investigate emulsion dynamics and the drops interaction.

  4. Invert emulsion well servicing fluids

    Microsoft Academic Search

    Carnicom

    1982-01-01

    An invert emulsion well servicing fluid containing an oleaginous phase, an aqueous phase, an invert emulsifier and an effective amount of a solid, particulate polyolefin having a density of about 0.90 gms\\/cc or greater.

  5. Lipid emulsions in parenteral nutrition.

    PubMed

    Adolph, M

    1999-01-01

    Lipid emulsions containing a physical mixture of medium and long chain triglycerides (MCT/LCT) are a well-proven concept in parenteral nutrition of critically ill patients. Having a demonstrably higher utilization rate, MCT/LCT emulsions do not impair liver function, produce less immune and no reticuloendothelial system function compromise, and do not interfere with pulmonary hemodynamics or gas exchange. A reduced content of n-6 polyunsaturated fatty acids can also be obtained by using newer preparations based on structured triglycerides or olive oil. Further studies are necessary in order to investigate these new lipid emulsions versus the physical mixture of MCT/LCT. A promising substrate in the development of lipid emulsions can be seen in fish oils. With regard to current literature, fish oils have a beneficial influence on the pathophysiological response to endotoxins and exert important modulations on eicosanoid and cytokine biology. Furthermore their intravenous use may improve organ perfusion in different critical situations. PMID:10364625

  6. Thermocapillary Motion in an Emulsion

    NASA Technical Reports Server (NTRS)

    Pukhnachov, Vladislav V.; Voinov, Oleg V.

    1996-01-01

    The phenomenological model for the motion of an emulsion or a gas-liquid mixture exposed to thermocapillary forces and micro-acceleration is formulated. The analytical and numerical investigation of one-dimensional flows for these media is fulfilled, the structure of discontinuous motion is studied. The stability conditions of a space-uniform state and of the interface between an emulsion and a pure liquid are obtained.

  7. Well treatment with emulsion dispersions

    Microsoft Academic Search

    C. E. Cooke; N. N. Li; T. W. Muecke; W. M. Salathiel

    1982-01-01

    In a method of treating a subterranean formation, a well treatment composition comprising a dispersion of a water-in-oil emulsion in an aqueous medium is injected into the formation. The water-in-oil emulsion has an internal aqueous phase and an external phase containing a liquid hydrocarbon and a surfactant soluble in the hydrocarbon. The compositions can be designed to perform various well

  8. Well treatment with emulsion dispersions

    Microsoft Academic Search

    C. E. Cooke; N. N. Li; T. W. Muecke; W. M. Salathiel

    1980-01-01

    A method of treating a subterranean formation wherein a well treatment composition comprising a dispersion of a water-in-oil emulsion in an aqueous medium is injected into the formation. The water-in-oil emulsion has an internal aqueous phase and an external phase containing a liquid hydrocarbon and a surfactant soluble in the hydrocarbon. The compositions can be designed to perform various well

  9. Put the breaks on wastewater emulsions

    SciTech Connect

    Alther, G. [Biomin, Inc., Ferndale, MI (United States)

    1998-03-01

    Emulsions in wastewater pose a vexing problem for facilities attempting to recycle water and stay in compliance with permissible discharge limits. But the challenges are no less formidable for routine maintenance. The removal of emulsions, a major constituent of which are fats, oils and greases (FOGs), is necessary to prevent them from depositing on pipes and fouling filtration media. Some of the havoc caused by emulsions can be avoided if emulsions are broken and removed from wastewater streams. Successful emulsion breaking requires a basic understanding of emulsions, their chemical composition, and the technologies required to remove them from water. The paper discusses emulsion basics and emulsion breaking, including counteracting emulsions, testing procedures, physical separation methods, removal strategies, bentonite-based powders, and post-polishing.

  10. Characterization of Surfactant Free Emulsions

    NASA Astrophysics Data System (ADS)

    Brar, Ramaninder; Urquidi, Jacob

    2012-10-01

    There is a pharmacological interest in providing a delivery mechanism for highly hydrophobic drugs through the bloodstream. A typical methodology would be to introduce a surfactant which would serve to bind the hydrophobic molecule to the aqueous environment. Because of the need for the surfactant to be non-toxic this avenue proves problematic and many highly hydrophobic drugs which could prove effective are not useable. We have demonstrated the formation of a stable emulsion of Silicone Oil in degassed water alone. The emulsion droplets were on the order of 50 nm in diameter and stable over a period of 8 hours. Previous studies have shown that the surfactant free emulsions do not lose their stability when the previously removed gasses are reintroduced. The formation of a stable emulsion in the complete absence of a surfactant could provide an alternative approach to a physiologically safe drug carrier. The present work involves the formation of stabilized surfactant free emulsions in a homologous series from pentane through decane. The emulsion's structure and thermodynamic stability were then characterized using small angle x-ray scattering.

  11. Coalescence in double emulsions.

    PubMed

    Chávez-Páez, Martín; Quezada, Carla M; Ibarra-Bracamontes, Laura; González-Ochoa, Héctor O; Arauz-Lara, José Luis

    2012-04-10

    Coalescence processes in double emulsions, water-in-oil-in-water, are studied by optical microscopy. The time evolution of such systems is determined by the interplay of two coalescence processes, namely, between inner water droplets and between the inner water droplets and the continuous external water phase. The predominance of one of those processes over the other, regulated by the relative amount of hydrophilic and lipophilic surfactants, leads to different evolutions of the system. We present here results for a class of systems whose evolution follows a master behavior. We also implemented a computer simulation where the system is modeled as a spherical cavity filled with smaller Brownian spheres. Collisions between spheres allow coalescence between them with probability P(i), whereas collisions between a sphere and the wall of the cavity allow coalescence with the external phase with probability P(e). The phenomenology observed in the experimental systems is well reproduced by the computer simulation for suitable values of the probability parameters. PMID:22429101

  12. Arrested of coalescence of emulsion droplets of arbitrary size

    NASA Astrophysics Data System (ADS)

    Mbanga, Badel L.; Burke, Christopher; Blair, Donald W.; Atherton, Timothy J.

    2013-03-01

    With applications ranging from food products to cosmetics via targeted drug delivery systems, structured anisotropic colloids provide an efficient way to control the structure, properties and functions of emulsions. When two fluid emulsion droplets are brought in contact, a reduction of the interfacial tension drives their coalescence into a larger droplet of the same total volume and reduced exposed area. This coalescence can be partially or totally hindered by the presence of nano or micron-size particles that coat the interface as in Pickering emulsions. We investigate numerically the dependance of the mechanical stability of these arrested shapes on the particles size, their shape anisotropy, their polydispersity, their interaction with the solvent, and the particle-particle interactions. We discuss structural shape changes that can be induced by tuning the particles interactions after arrest occurs, and provide design parameters for the relevant experiments.

  13. First results on proton radiography with nuclear emulsion detectors

    E-print Network

    Braccini, S; Kreslo, I; Moser, U; Pistillo, C; Studer, S; Scampoli, P; Coray, A; Pedroni, E

    2010-01-01

    We propose an innovative method for proton radiography based on nuclear emulsion film detectors, a technique in which images are obtained by measuring the position and the residual range of protons passing through the patient's body. For this purpose, nuclear emulsion films interleaved with tissue equivalent absorbers can be used to reconstruct proton tracks with very high accuracy. This is performed through a fully automated scanning procedure employing optical microscopy, routinely used in neutrino physics experiments. Proton radiography can be used in proton therapy to obtain direct information on the average tissue density for treatment planning optimization and to perform imaging with very low dose to the patient. The first prototype of a nuclear emulsion based detector has been conceived, constructed and tested with a therapeutic proton beam. The first promising experimental results have been obtained by imaging simple phantoms.

  14. First results on proton radiography with nuclear emulsion detectors

    NASA Astrophysics Data System (ADS)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Moser, U.; Pistillo, C.; Studer, S.; Scampoli, P.; Coray, A.; Pedroni, E.

    2010-09-01

    We propose an innovative method for proton radiography based on nuclear emulsion film detectors, a technique in which images are obtained by measuring the position and the residual range of protons passing through the patient's body. For this purpose, nuclear emulsion films interleaved with tissue equivalent absorbers can be used to reconstruct proton tracks with very high accuracy. This is performed through a fully automated scanning procedure employing optical microscopy, routinely used in neutrino physics experiments. Proton radiography can be used in proton therapy to obtain direct information on the average tissue density for treatment planning optimization and to perform imaging with very low dose to the patient. The first prototype of a nuclear emulsion based detector has been conceived, constructed and tested with a therapeutic proton beam. The first promising experimental results have been obtained by imaging simple phantoms.

  15. Optimizing organoclay stabilized Pickering emulsions.

    PubMed

    Cui, Yannan; Threlfall, Mhairi; van Duijneveldt, Jeroen S

    2011-04-15

    Oil-in-water emulsions were prepared using montmorillonite clay platelets, pre-treated with quaternary amine surfactants. In previous work, cetyl trimethylammonium bromide (CTAB) has been used. In this study, two more hydrophilic quaternary amine surfactants, Berol R648 and Ethoquad C/12, were used and formed Pickering emulsions, which were more stable than the emulsions prepared using CTAB coated clay. The droplets were also more mono-disperse. The most hydrophilic surfactant Berol R648 stabilizes the emulsions best. Salt also plays an important role in forming a stable emulsion. The droplet size decreases with surfactant concentration and relatively mono-disperse droplets can be obtained at moderate surfactant concentrations. The time evolution of the droplet size indicates a good stability to coalescence in the presence of Berol R648. Using polarizing microscopy, the clay platelets were found to be lying flat at the water oil interface. However, a significant fraction (about 90%) of clay stayed in the water phase and the clay particles at the water-oil interface formed stacks, each consisting of four clay platelets on average. PMID:21324469

  16. Oscillatory, creep and steady flow behavior of xanthan-thickened oil-in-water emulsions

    SciTech Connect

    Pal, R. [Univ. of Waterloo, Ontario (Canada). Dept. of Chemical Engineering] [Univ. of Waterloo, Ontario (Canada). Dept. of Chemical Engineering

    1995-04-01

    In the handling, mixing, storage, and pipeline transportation of emulsions, knowledge of rheological properties is required for the design, selection, and operation of the equipment involved. The rheological behavior of xanthan gum-thickened oil-in-water emulsions is studied with a cone-and-plate system using a constant-stress rheometer. Xanthan gum solutions and xanthan-thickened oil-in-water emulsions are strongly shear-thinning and viscoelastic in nature. The effects of polymer and oil concentrations on the rheological behavior of emulsions are investigated. The relative viscosity for the thickened emulsions, at any given oil concentration, increases with an increase in the shear rate, whereas the unthickened emulsions show the opposite trend. The theoretical models give reasonable predictions for the relative viscosity, storage modulus, and loss modulus of xanthan-thickened emulsions. The ratio of storage to loss moduli increases considerably with the increase in polymer and oil concentrations. The creep/recovery experiments confirm that the xanthan-thickened emulsions are highly viscoelastic in nature and that the degree of elasticity increases with the increase in polymer and oil concentrations.

  17. Rapid crystallization and morphological adjustment of zeolite ZSM-5 in nonionic emulsions

    SciTech Connect

    Zhang Ying, E-mail: yingzh1977@163.co [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China) and Department of Materials Science and Engineering, China University of Petroleum, 18 Fuxue Road, Changping District, Beijing 102249 (China); Jin Chao [Department of Materials Science and Engineering, China University of Petroleum, 18 Fuxue Road, Changping District, Beijing 102249 (China); Research Institute of Petroleum Processing, Beijing 100083 (China)

    2011-01-15

    Zeolite ZSM-5 was synthesized for the first time in a nonionic emulsion composed of polyoxyethylated alkylphenol, butanol, cyclohexane and tetraethylammonium hydroxide (TEAOH)-containing zeolite synthesis mixture. The crystallization kinetics in the emulsion was investigated and the ZSM-5 product was characterized in detail by XRD, SEM, FT-IR, TG, N{sub 2} adsorption and CHN analysis techniques. Compared with the conventionally hydrothermal synthesis with the same structure directing agent TEAOH, the emulsion system allows rapid crystallization of ZSM-5. The ZSM-5 product exhibits unusual agglomerated structure and possesses larger specific surface area. The FT-IR, TG results plus CHN analysis show the encapsulation of a trace of emulsion components in the emulsion ZSM-5. Control experiments show the emulsion system exerts the crystallization induction and morphological adjustment effects mainly during the aging period. The effects are tentatively attributed to the confined space domains, surfactant-water interaction as well as surfactant-growing crystals interaction existing in the emulsion. -- Graphical abstract: The nonionic emulsion synthesis allows rapid crystallization and morphological adjustment of zeolite ZSM-5 compared with the conventional hydrothermal synthesis. Display Omitted

  18. Emulsions stabilised solely by colloidal particles

    Microsoft Academic Search

    Robert Aveyard; Bernard P Binks; John H Clint

    2003-01-01

    The preparation and properties of emulsions, stabilised solely by the adsorption of solid particles at the oil–water interface, are reviewed especially in the light of our own work with particles of well-controlled surface properties. Where appropriate, comparison is made with the behaviour of surfactant-stabilised emulsions. Hydrophilic particles tend to form oil-in-water (o\\/w) emulsions whereas hydrophobic particles form water-in-oil (w\\/o) emulsions.

  19. Interfacial mechanisms in active emulsions.

    PubMed

    Herminghaus, Stephan; Maass, Corinna C; Krüger, Carsten; Thutupalli, Shashi; Goehring, Lucas; Bahr, Christian

    2014-09-28

    Active emulsions, i.e., emulsions whose droplets perform self-propelled motion, are of tremendous interest for mimicking collective phenomena in biological populations such as phytoplankton and bacterial colonies, but also for experimentally studying rheology, pattern formation, and phase transitions in systems far from thermal equilibrium. For fuelling such systems, molecular processes involving the surfactants which stabilize the emulsions are a straightforward concept. We outline and compare two different types of reactions, one which chemically modifies the surfactant molecules, the other which transfers them into a different colloidal state. While in the first case symmetry breaking follows a standard linear instability, the second case turns out to be more complex. Depending on the dissolution pathway, there is either an intrinsically nonlinear instability, or no symmetry breaking at all (and hence no locomotion). PMID:24924906

  20. Advances with holographic DESA emulsions

    NASA Astrophysics Data System (ADS)

    Dünkel, Lothar; Eichler, Jürgen; Schneeweiss, Claudia; Ackermann, Gerhard

    2006-02-01

    DESA emulsions represent layer systems based on ultra-fine grained silver halide (AgX) technology. The new layers have an excellent performance for holographic application. The technology has been presented repeatedly in recent years, including the emulsion characterization and topics of chemical and spectral sensitization. The paper gives a survey of actual results referring to panchromatic sensitization and other improvements like the application of silver halide sensitized gelatine (SHSG) procedure. These results are embedded into intensive collaborations with small and medium enterprises (SME's) to commercialize DESA layers. Predominant goals are innovative products with holographic components and layers providing as well as cost effectiveness and high quality.

  1. Advances in Intravenous Lipid Emulsions

    Microsoft Academic Search

    2000-01-01

    Over the past decade, our views have\\u000a considerably evolved with respect to the metabolism of intravenous\\u000a lipid emulsions and their composition. Substantial progress has been\\u000a made in understanding the metabolic pathways of emulsion particles and\\u000a the delivery of their various components (fatty acids and vitamins) to\\u000a specific tissues or cells. Although soybean long-chain triglycerides\\u000a represent a valuable source of energy,

  2. Technical optimisation of redispersible dry emulsions.

    PubMed

    Christensen, K L; Pedersen, G P; Kristensen, H G

    2001-01-16

    Preparation of dry emulsions suitable for tablet processing was examined in this study. Liquid o/w-emulsions were spray dried in a laboratory spray dryer applying hydroxypropylmethylcellulose (HPMC) as a solid carrier and emulsifier. As the lipid phase, fractionated coconut oil was used. The ability of various excipients to increase the density of dry emulsions was investigated. Adding sucrose to the formulation, redispersible dry emulsions with higher density were obtained. The type of rotary atomizer did not affect the dry emulsions containing sucrose nor the rate of rotation of the atomizer applied in the spray drying process. By wet granulation, using ethanol as a binder, free-flowing and compactable dry emulsions were obtained and simultaneously the reconstitution properties were preserved. It was concluded that dry emulsions could be optimised for tablet processing by wet granulation. Tablets having a lipid content up to 20% had proper tablet properties. PMID:11165077

  3. Hollandaise Sauce: Emulsion at Work

    NSDL National Science Digital Library

    Exploratorium

    2012-10-03

    In this activity, learners follow a recipe to make hollandaise sauce. Learners discover how cooks use egg yolks to blend oil and water together into a smooth mix. In chemistry, this mixture is known as an emulsion. Substances like egg yolks that assist with emulsification are called emulsifiers.

  4. Lipid oxidation in food emulsions

    Microsoft Academic Search

    John N. Coupland; D. Julian McClements

    1996-01-01

    Lipid oxidation is a major cause of quality deterioration in food emulsions. The design of foods with improved quality depends on a better understanding of the physicochemical mechanisms of lipid oxidation in these systems. The oxidation of emulsified lipids differs from that of bulk lipids, because of the presence of the droplet membrane, the interactions between the ingredients, and the

  5. Experimental Characterization of Canola Oil Emulsion Combustion in a Modified Furnace

    E-print Network

    Bhimani, Shreyas Mahesh

    2012-07-16

    , the surfactant is called an anionic surfactant and if the charge is positive, it is called a cationic surfactant. There are surfactants whose heads have two oppositely charged groups. They are referred to as zwitterionic/amphoteric surfactants. 2. Nonionic... oil emulsion with 2% surfactant (w/w)] and 85-12.5 emulsion [12.5% methanol ? in ? 85% canola oil (w/w) emulsion with 2.5% surfactant]. All the combustion experiments were conducted for a constant heat output of 72,750 kJ/hr. One of the major...

  6. Adelphi-Goddard emulsified fuel project. [using water/oil emulsions

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Thermal efficiency and particle emissions were studied using water/oil emulsions. These studies were done using number 2 and number 6 fuel oil. The number 6 oil had a sulfur content greater than one percent and experiments were conducted to remove the sulfur dioxide from the stack gases. Test findings include: (1) emulsion effected a reduction in soot at a low excess air levels; (2) a steam atomizing system will produce a water/oil emulsion. The fuel in the study was emulsified in the steam atomization process, hence, pre-emulsification did not yield a dramatic reduction in soot or an increase in thermal efficiency.

  7. Measurement of dileptons with the CBM experiment at FAIR

    NASA Astrophysics Data System (ADS)

    Höhne, C.

    2014-11-01

    The Compressed Baryonic Matter (CBM) experiment at the upcoming Facility for Antiproton and Ion Research (FAIR) will explore the phase diagram of nuclear matter at very high net-baryon densities and moderate temperatures in nucleus-nucleus collisions at beam energies up to 45 A GeV. One of the key diagnostic probes is electromagnetic radiation. In order to minimize systematic errors of this challenging measurement, CBM aims at an investigation of dielectron and dimuon pairs in the full mass range from the photon point up to charmonium. The results of performance studies for dilepton measurements and the status of the detector developments are presented.

  8. Polymerization in emulsion microdroplet reactors

    NASA Astrophysics Data System (ADS)

    Carroll, Nick J.

    The goal of this research project is to utilize emulsion droplets as chemical reactors for execution of complex polymerization chemistries to develop unique and functional particle materials. Emulsions are dispersions of immiscible fluids where one fluid usually exists in the form of drops. Not surprisingly, if a liquid-to-solid chemical reaction proceeds to completion within these drops, the resultant solid particles will possess the shape and relative size distribution of the drops. The two immiscible liquid phases required for emulsion polymerization provide unique and complex chemical and physical environments suitable for the engineering of novel materials. The development of novel non-ionic fluorosurfactants allows fluorocarbon oils to be used as the continuous phase in a water-free emulsion. Such emulsions enable the encapsulation of almost any hydrocarbon compound in droplets that may be used as separate compartments for water-sensitive syntheses. Here, we exemplify the promise of this approach by suspension polymerization of polyurethanes (PU), in which the liquid precursor is emulsified into droplets that are then converted 1:1 into polymer particles. The stability of the droplets against coalescence upon removal of the continuous phase by evaporation confirms the formation of solid PU particles. These results prove that the water-free environment of fluorocarbon based emulsions enables high conversion. We produce monodisperse, cross-linked, and fluorescently labeled PU-latexes with controllable mesh size through microfluidic emulsification in a simple one-step process. A novel method for the fabrication of monodisperse mesoporous silica particles is presented. It is based on the formation of well-defined equally sized emulsion droplets using a microfluidic approach. The droplets contain the silica precursor/surfactant solution and are suspended in hexadecane as the continuous oil phase. The solvent is then expelled from the droplets, leading to concentration and micellization of the surfactant. At the same time, the silica solidifies around the surfactant structures, forming equally sized mesoporous particles. The procedure can be tuned to produce well-separated particles or alternatively particles that are linked together. The latter allows us to create 2D or 3D structures with hierarchical porosity. Oil, water, and surfactant liquid mixtures exhibit very complex phase behavior. Depending on the conditions, such mixtures give rise to highly organized structures. A proper selection of the type and concentration of surfactants determines the structuring at the nanoscale level. In this work, we show that hierarchically bimodal nanoporous structures can be obtained by templating silica microparticles with a specially designed surfactant micelle/microemulsion mixture. Tuning the phase state by adjusting the surfactant composition and concentration allows for the controlled design of a system where microemulsion droplets coexist with smaller surfactant micellar structures. The microemulsion droplet and micellar dimensions determine the two types of pore sizes (single nanometers and tens of nanometers). We also demonstrate the fabrication of carbon and carbon/platinum replicas of the silica microspheres using a "lost-wax" approach. Such particles have great potential for the design of electrocatalysts for fuel cells, chromatography separations, and other applications. It was determined that slight variations in microemulsion mixture components (electrolyte concentration, wt% of surfactants, oil to sol ratio, etc.) produces strikingly different pore morphologies and particle surface areas. Control over the size and structure of the smaller micelle-templated pores was made possible by varying the length of the hydrocarbon block within the trimethyl ammonium bromide surfactant and characterized using X-ray diffraction. The effect of emulsion aging was studied by synthesizing particles at progressive time levels from a sample emulsion. It was discovered surface pore size increases after just a few hours, with

  9. Formation of curcumin nanoparticles by flash nanoprecipitation from emulsions.

    PubMed

    Margulis, Katherine; Magdassi, Shlomo; Lee, Han Seung; Macosko, Christopher W

    2014-11-15

    Nanometric particles of a model hydrophobic substance curcumin were prepared by a novel method, namely, flash nanoprecipitation from a coarse oil-in-water emulsion. The method employs turbulent co-mixing of water with curcumin-loaded emulsion using manually-operated confined impingement jets mixer. A clear and stable dispersion of nanoparticles was formed in this process, and could be converted to dry, easily water-dispersible powder by spray drying. The mean size of the particles was about 40 nm by DLS, confirmed by Cryo-TEM. The obtained particles contained 20.4 wt% curcumin, X-ray analysis showed it was amorphous. The significant advantages of the studied process are its feasibility, speed and low cost. It does not require any special high-energy input equipment to reduce the droplet size of the initial emulsion as required by the vast majority of other methods, and relies on rapid turbulent mixing and on flow-induced shear stress formed in the simple, manually-operated mixer. Control experiments clearly indicate that employing emulsion, instead of a plain solution and flash nanoprecipitation instead of a simple antisolvent precipitation are advantageous in terms of particle size and stability. PMID:25168584

  10. Optimization of tocol emulsions for the intravenous delivery of clarithromycin.

    PubMed

    Li, Jie; Nie, Shufang; Yang, Xingang; Wang, Changguang; Cui, Shuxia; Pan, Weisan

    2008-05-22

    In the present study, novel less-painful tocol emulsions for the intravenous delivery of clarithromycin were prepared and optimized. The therapeutically effective concentration of clarithromycin, 5mg/ml, was achieved using tocopherol succinate (TS) combined with oleic acid as lipophilic counterions. The possibility of employing the microdialysis technique to investigate the distribution of the drug in emulsions was explored. A three-level three-factorial Box-Behnken experimental design was utilized to conduct the experiments. The effects of selected variables, tocopherol succinate/oleic acid relation, poloxamer 188 content and 0.1M NaOH amount, on three considered responses were investigated. The particle size, zeta potential and the oil phase distribution of clarithromycin for the optimized formulation were observed to be 138.5 nm, -32.16 mV and 97.28%, respectively. The emulsions prepared with the optimized formula demonstrated good physical stability during storage at 4 degrees C and room temperature. The histopathological examination for rabbit ear vein irritation test indicated that the irritation of clarithromycin could be eliminated by formulating the drug in a tocol emulsion. PMID:18289806

  11. Use of micro-emulsion technology for the directed evolution of antibodies.

    PubMed

    Buhr, Diane L; Acca, Felicity E; Holland, Erika G; Johnson, Katie; Maksymiuk, Gail M; Vaill, Ada; Kay, Brian K; Weitz, David A; Weiner, Michael P; Kiss, Margaret M

    2012-09-01

    Affinity reagents, such as antibodies, are needed to study protein expression patterns, sub-cellular localization, and post-translational modifications in complex mixtures and tissues. Phage Emulsion, Secretion, and Capture (ESCape) is a novel micro-emulsion technology that utilizes water-in-oil (W/O) emulsions for the identification and isolation of cells secreting phage particles that display desirable antibodies. Using this method, a large library of antibody-displaying phage will bind to beads in individual compartments. Rather than using biopanning on a large mixed population, phage micro-emulsion technology allows us to individually query clonal populations of amplified phage against the antigen. The use of emulsions to generate microdroplets has the promise of accelerating phage selection experiments by permitting fine discrimination of kinetic parameters for binding to targets. In this study, we demonstrate the ability of phage micro-emulsion technology to distinguish two scFvs with a 300-fold difference in binding affinities (100nM and 300pM, respectively). In addition, we describe the application of phage micro-emulsion technology for the selection of scFvs that are resistant to elevated temperatures. PMID:22819852

  12. Stability of emulsions of water in oil. I. The correlation between electrokinetic potential and stability

    Microsoft Academic Search

    W. Albers; J. Th. G. Overbeek

    1959-01-01

    Experiments on W\\/O emulsions of moderate concentration, stabilized with oil-soluble, ionizing stabilizers, show that in these emulsions no correlation exists between stability against flocculation and electrokinetic potential. Although, according to theoretical calculations, energy barriers of over 15 kT are present, if the radius of the dispersed globules is about 1 ? and the electrokinetic potential exceeds 25 mv., they apparently

  13. Measuring the Free Fall of Antihydrogen with Emulsion Detectors

    NASA Astrophysics Data System (ADS)

    Pistillo, C.

    2014-06-01

    The AEgIS experiment at CERN is designed to perform the first direct measurement of gravitational interaction between antimatter and matter by detecting the fall of a horizontally accelerated cold antihydrogen beam in the Earth's gravitational field. The spatial resolution of the position sensitive detector is a key issue for the success of the experiment. For this reason, the employment of emulsion film detectors is being considered and an intense R&D is being conducted to define the use of this technology in the AEgIS apparatus. We present the results of test beams conducted in 2012, when emulsion film detectors were directly exposed to a ˜ 100 keV antiproton beam and annihilation vertices successfully reconstructed with a few micrometers resolution. The prospects for the realization of the final detector are also presented.

  14. Controlled Generation of Double Emulsions in Air

    PubMed Central

    liu, Dingsheng; Hakimi, Bejan; Volny, Michael; Rolfs, Joelle; Chen, Xudong; Turecek, Frantisek; Chiu, Daniel T.

    2013-01-01

    This communication describes the controlled generation of double emulsions in the gas phase, which was carried out using an integrated emitter in a PDMS (poly(dimethylsiloxane)) microfluidic chip. The integrated emitter was formed using a molding approach, in which metal wires with desirable diameters were used as emitter molds. The generation of double emulsions in air was achieved with electrohydrodynamics actuation, which offers controllable force exerting on the double emulsions. We developed this capability for future integration of droplet microfluidics with mass spectrometry (MS), where each aqueous droplet in the microchannel is introduced into the gas phase as a double emulsion for subsequent ionization and MS analysis. PMID:23767768

  15. Solvent Extraction and Emulsion Separation in Magnetic Fields

    Microsoft Academic Search

    W. Palyska; A. G. Chmielewski

    1993-01-01

    In two-phase emulsion separations, it is customary to employ large settling volumes (for mixer-settling apparatus) or large centrifugal forces (for centrifugal contactors). Improvement can sometimes be achieved by using an extractant with magnetic properties in the presence of a variable field. In the work reported in this paper, two different extractants (D-2EHPA and TBP) were employed in magnetic field experiments.

  16. Perfluorochemical emulsions can increase tumor radiosensitivity

    Microsoft Academic Search

    B. A. Teicher; C. M. Rose

    1984-01-01

    An oxygen-carrying perfluorochemical emulsion enhanced the effectiveness of radiation therapy in two transplantable solid tumors in mice. The perfluorochemical emulsion had no effect on tumor growth after x-irradiation, but delayed tumor growth significantly when administered to oxygen-breathing mice before or during irradiation.

  17. Treatment of oil-in-water emulsions

    SciTech Connect

    Presley, C.T.; Harrison, R.J.

    1980-01-08

    Petroleum is separated from an oil-in-water emulsion containing water-soluble polymer such as polyacrylamide prior to refining by adding amphoteric metal cations (Zn, Al, Sn, and Co) to the emulsion to form a flocculate and then treating the resulting flocculate with a strong base to recover the oil and metal. 11 claims.

  18. Treatment of oil-in-water emulsions

    SciTech Connect

    Harrison, R.J.; Presley, C.T.

    1980-01-08

    Petroleum is separated from an ''oil-in-water'' emulsion containing water-soluble polymer prior to refining by adding amphoteric metal cations to the emulsion to form a flocculate and then treating the resulting flocculate with a strong base to recover the oil and metal.

  19. Flows of Wet Foamsand Concentrated Emulsions

    NASA Technical Reports Server (NTRS)

    Nemer, Martin B.

    2005-01-01

    The aim of this project was is to advance a microstructural understanding of foam and emulsion flows. The dynamics of individual surfactant-covered drops and well as the collective behavior of dilute and concentrated was explored using numerical simulations. The long-range goal of this work is the formulation of reliable microphysically-based statistical models of emulsion flows.

  20. Metallic nanoshells on porphyrin-stabilized emulsions

    DOEpatents

    Wang, Haorong; Song, Yujiang; Shelnutt, John A; Medforth, Craig J

    2013-10-29

    Metal nanostructures formed by photocatalytic interfacial synthesis using a porphyrin-stabilized emulsion template and the method for making the nanostructures. Catalyst-seeded emulsion droplets are employed as templates for hollow-nanoshell growth. The hollow metal nanospheres may be formed with or without inclusions of other materials.

  1. Coalescence in concentrated Pickering emulsions under shear.

    PubMed

    Whitby, Catherine P; Krebsz, Melinda

    2014-07-21

    We have investigated the rheology of concentrated oil-in-water emulsions stabilised by silanised silica nanoparticles. The emulsions behave like highly elastic solids in response to small, uniform strains. They become unstable and begin to break down, however, on yielding. We show that the emulsion elasticity is correlated with the salt concentration in the water and hence the particle aggregation in emulsions at a given drop volume fraction. A supporting observation is that destabilisation is favoured by minimising the attractive interactions between the particles. Microscopic observations revealed that coalesced drops have anisotropic shapes and wrinkled surfaces, direct evidence of the interfacial particle layer acting like a mechanical barrier to bulk emulsion destabilisation. PMID:24862445

  2. Destabilization of emulsions by natural minerals.

    PubMed

    Yuan, Songhu; Tong, Man; Wu, Gaoming

    2011-09-15

    This study developed a novel method to destabilize emulsions and recycle oils, particularly for emulsified wastewater treatment. Natural minerals were used as demulsifying agents, two kinds of emulsions collected from medical and steel industry were treated. The addition of natural minerals, including artificial zeolite, natural zeolite, diatomite, bentonite and natural soil, could effectively destabilize both emulsions at pH 1 and 60 °C. Over 90% of chemical oxygen demand (COD) can be removed after treatment. Medical emulsion can be even destabilized by artificial zeolite at ambient temperature. The mechanism for emulsion destabilization by minerals was suggested as the decreased electrostatic repulsion at low pH, the enhanced gathering of oil microdroplets at elevated temperature, and the further decreased surface potential by the addition of minerals. Both flocculation and coalescence were enhanced by the addition of minerals at low pH and elevated temperature. PMID:21784583

  3. Emulsion ripening through molecular exchange at droplet contacts.

    PubMed

    Roger, Kevin; Olsson, Ulf; Schweins, Ralf; Cabane, Bernard

    2015-01-26

    Two coarsening mechanisms of emulsions are well established: droplet coalescence (fusion of two droplets) and Ostwald ripening (molecular exchange through the continuous phase). Here a third mechanism is identified, contact ripening, which operates through molecular exchange upon droplets collisions. A contrast manipulated small-angle neutron scattering experiment was performed to isolate contact ripening from coalescence and Ostwald ripening. A kinetic study was conducted, using dynamic light scattering and monodisperse nanoemulsions, to obtain the exchange key parameters. Decreasing the concentration or adding ionic repulsions between droplets hinders contact ripening by decreasing the collision frequency. Using long surfactant chains and well-hydrated heads inhibits contact ripening by hindering fluctuations in the film. Contact ripening can be controlled by these parameters, which is essential for both emulsion formulation and delivery of hydrophobic ingredients. PMID:25504340

  4. A surfactantless emulsion as a model for the liquid-liquid interface

    NASA Astrophysics Data System (ADS)

    Knight, Katherine Mary

    An electrochemically polarised liquid-liquid interface in the form of a surfactantless oil-in-water emulsion has been developed, and its creation, stabilisation and use as a model liquid-liquid system for structural characterisation using Small Angle Neutron Scattering (SANS) are described. The emulsion, composed of 1,2-dichloroethane (DCE)-in-D20, was created using a condensation method and the two main processes of destabilisation, sedimentation and coalescence, were minimised using density-matching and electrochemistry. The stabilised emulsion interface was then studied with SANS, using the Dll and D22 diffractometers at the ILL and LOQ at ISIS. This was to determine structural information regarding a layer of adsorbed Bovine Serum Albumin (BSA) protein at the interface with and without stabilising salts and the only analysable results were obtained using Dll, due to the lower Q-range accessible. The BSA layer thickness was determined to be 40 and 48 A for emulsions with and without salts respectively, and this was comparable with the literature thickness of 40 A. Another use for the surfactantless emulsion would be for electrodeless electrodeposition of metals at the interface, utilising the interfacial potential, and preliminary experiments were carried out using both oil-in-water and water-in-oil emulsions.

  5. Subthreshold Antiproton Production in Nucleus-Nucleus Collisions

    E-print Network

    Ko, Che Ming; Xia, L. H.

    1989-01-01

    Department, Nankai University, Tianjin, People's Republic of China. ~ J. B.Carrol et al. , Phys. Rev. Lett. 62, 1829 (1989). 2A. Shor, V. Perez-Mendez, and K. Ganezer, Lawrence Berke- ley Laboratory Report No. LBL-17067, 1984 (unpublished). 3C. M. Ko...

  6. Baryon distributions in ultrarelativistic nucleus-nucleus collisions

    Microsoft Academic Search

    J. Barrette; R. Bellwied; P. Braun-Munzinger; W. E. Cleland; T. M. Cormier; G. David; J. Dee; G. E. Diebold; O. Dietzsch; J. V. Germani; S. Gilbert; S. V. Greene; J. R. Hall; T. K. Hemmick; N. Herrmann; B. Hong; K. Jayananda; D. Kraus; B. Shiva Kumar; R. Lacasse; D. Lissauer; W. J. Llope; T. W. Ludlam; S. McCorkle; R. Majka; S. K. Mark; J. T. Mitchell; M. Muthuswamy; E. O'Brien; C. Pruneau; M. N. Rao; F. Rotondo; J. Sandweiss; N. C. daSilva; U. Sonnadara; J. Stachel; H. Takai; E. M. Takagui; T. G. Throwe; C. Winter; G. Wang; D. Wolfe; C. L. Woody; N. Xu; Y. Zhang; Z. Zhang; C. Zou

    1993-01-01

    We have measured distributions in transverse momentum and rapidity of protons from interactions of 14.6 GeV\\/nucleon28Si projectiles with targets of Al and Pb. The transverse momentum spectra exhibit a thermal shape with a rapidity dependent temperature parameter. For very central or violent collisions the proton rapidity distributions exhibit the large rapidity shifts and (for Si+Al) a peak at midrapidity as

  7. Spectator fragmentation in nucleus-nucleus collisions: Phase space approach

    E-print Network

    Yogesh K. Vermani; Ashok Jangid

    2011-08-29

    Dynamics of spectator matter break-up in non-central collisions of $^{197}$Au+ $^{197}$Au at 1000 AMeV are explored within framework of quantum molecular dynamics (QMD) model. The phase space of nucleons bound in intermediate mass fragments are studied using two clusterization subroutines. Backtracking the origin of fragments to the time of initial contact between colliding nuclei indicates that \\textit{simulated annealing clusterization algorithm} (SACA) results into significant yield of projectile-like and target-like fragments. Simplest clusterization approach based on spatial correlation technique, however, predicted much lesser production probability of fragments in spectator zone.

  8. Neutron Spectra from Intermediate-Energy Nucleus-Nucleus Reactions

    NASA Astrophysics Data System (ADS)

    Iwase, Hiroshi; Iwata, Yoshiyuki; Nakamura, Takashi; Gudima, Konstantin; Mashnik, Stepan; Sierk, Arnold; Prael, Richard

    2005-05-01

    Double-differential cross sections of neutron production at angles from 0 to 110 degrees from many reactions induced by light and medium nuclei on targets from 12C to 208Pb, at several incident energies from 95 to 600 MeV/nucleon have been measured recently at the Institute of Physical and Chemical Research (RIKEN) Ring Cyclotron in Japan and at the Heavy-Ion Medical Accelerator of the National Institute of Radiological Science in Chiba, Japan using the time-of-flight technique. We have analyzed all these new measurements using the Quantum Molecular Dynamics (QMD) model, the Oak Ridge intranuclear cascade model HIC, the ISABEL intranuclear cascade model from LAHET, and the Los Alamos version of the Quark-Gluon String Model code LAQGSM03. On the whole, all four models used here describe reasonably well most of the measured neutron spectra, although different models agree differently with data from specific reactions and some serious discrepances are observed for some reactions. We present here some illustrative results from our study, discuss possible reasons for some of the observed discrepancies and try to outline ways to further improve the tested codes in order to address these problems.

  9. Monodisperse Double Emulsions Generated from a Microcapillary Device

    Microsoft Academic Search

    A. S. Utada; E. Lorenceau; P. D. Kaplan; H. A. Stone; D. A. Weitz

    2005-01-01

    Double emulsions are highly structured fluids consisting of emulsion drops that contain smaller droplets inside. Although double emulsions are potentially of commercial value, traditional fabrication by means of two emulsification steps leads to very ill-controlled structuring. Using a microcapillary device, we fabricated double emulsions that contained a single internal droplet in a core- shell geometry. We show that the droplet

  10. Breakup of double emulsions in constrictions Haosheng Chen,ab

    E-print Network

    Breakup of double emulsions in constrictions Haosheng Chen,ab Jiang Li,cd Ho Cheung Shum,a Howard A We report the controlled breakup of double emulsion droplets as they flow through an orifice. Double emulsions, which were originally referred to as emulsion liquid membranes, were conceived

  11. Supporting Information Self-Assembled Liquid Crystal Gels in Emulsion

    E-print Network

    Zhao, Yue

    Supporting Information Self-Assembled Liquid Crystal Gels in Emulsion Xia Tong,1 Jong Won Chung,2 emulsion. Fig. S1. Image a is the photomicrograph (reflection mode) of an emulsion cast on a glass slide. Polarizing photomicrographs showing (a) the droplets of liquid crystal emulsion without gelator and (b

  12. Cometabolic Degradation of TCE Vapors in a Foamed Emulsion

    E-print Network

    Cometabolic Degradation of TCE Vapors in a Foamed Emulsion Bioreactor E U N S U N G K A N A N D M)vaporsinanovelgas-phasebioreactorcalledthefoamed emulsion bioreactor (FEBR) was demonstrated. Toluene vapors were used as the primary growth substrate-phase bioreactor called the foamed emulsion bioreactor (FEBR) was developed (20). The FEBR consists of an emulsion

  13. Slowly and rapidly digested fat emulsions are equally satiating but their triglycerides are differentially absorbed and metabolized in humans.

    PubMed

    Keogh, Jennifer B; Wooster, Tim J; Golding, Matthew; Day, Li; Otto, Bärbel; Clifton, Peter M

    2011-05-01

    Little is known about the effect of dietary fat emulsion microstructure on plasma TG concentrations, satiety hormones, and food intake. The aim of this study was to structure dietary fat to slow digestion and flatten postprandial plasma TG concentrations but not increase food intake. Emulsions were stabilized by egg lecithin (control), sodium sterol lactylate, or sodium caseinate/monoglyceride (CasMag) with either liquid oil or a liquid oil/solid fat mixture. In a randomized, double-blind, crossover design, 4 emulsions containing 30 g of fat in a 350-mL preload were consumed by 10 men and 10 women (BMI = 25.1 ± 2.8 kg/m(2); age = 58.8 ± 4.8 y). Pre- and postprandial plasma TG, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), and peptide YY (PYY) concentrations and food intake were measured. In a second experiment in a subset of the participants (n = 8, 4 men and 4 women), (13)C-labeled mixed TG was incorporated into 2 different emulsions and breath (13)C was measured over 6 h. In the first experiment, the postprandial rise in plasma TG concentrations following the CasMag-stabilized emulsion containing 30% solid fat was lower than all other emulsions at 90 and 120 min (P < 0.05). Plasma CCK (P < 0.0001), GLP-1 (P < 0.01), and PYY (P < 0.001) concentrations were also reduced following this emulsion compared with control. Food intake at a test meal, eaten 3 h after the preload, did not differ among the emulsions. In the second experiment, when measured by the (13)C breath test, 25% of the TG in the CasMag emulsion was absorbed and metabolized compared with control. In conclusion, fat can be structured to decrease its effect on plasma TG concentrations without increasing food intake. PMID:21411612

  14. Drops deformation and magnetic permeability of a ferrofluid emulsion

    E-print Network

    Arthur Zakinyan; Yury Dikansky

    2011-04-17

    In the paper the novel soft magnetic composite system is investigated. A ferrofluid emulsion studied demonstrates the strong magnetic properties which are atypical for commonly known emulsions. Interaction of ferrofluid emulsions with a magnetic field is considered. Structural transformations in these media, such as deformation of emulsion microdroplets and emulsion inversion, are studied. The changes in the relative permeability of emulsion associated with structural transformations are investigated. The theory of the observed phenomena is developed, and the feasibility of effectively controlling the magnetic properties of ferrofluid emulsions by applying a magnetic field is demonstrated.

  15. Effect of Emulsifiers and Their Liquid Crystalline Structures in Emulsions on Dermal and Transdermal Delivery of Hydroquinone, Salicylic Acid and Octadecenedioic Acid

    Microsoft Academic Search

    A. Otto; J. W. Wiechers; C. L. Kelly; J. C. Dederen; J. Hadgraft; J. du Plessis

    2010-01-01

    This study investigated the effect of emulsifiers and their liquid crystalline structures on the dermal and transdermal delivery of hydroquinone (HQ), salicylic acid (SA) and octadecenedioic acid (DIOIC). Emulsions containing liquid crystalline phases were compared with an emulsion without liquid crystals. Skin permeation experiments were performed using Franz-type diffusion cells and human abdominal skin dermatomed to a thickness of 400

  16. Emulsions on demand using microsturctured devices

    NASA Astrophysics Data System (ADS)

    Mahe, Christian; Tranchant, Jean Francois; Tromeur, Melanie; Schwesinger, Norbert

    2003-01-01

    Emulsions are very common in the field of cosmetics. Unfortunately, most emulsions contain ineffective substances to increase the stability of the products for a long time. These stabilizers can cause some severe healthy problems in several cases. One possible solution is the production of emulsions on demand to prevent the use of stabilizers. Stable emulsion can be achieved if the diameters of the droplets of one solution surrounded by a second solution are smaller than 1?m. Microstructured devices are suited in principle to generate such droplet distributions. Basic task of the development was a micro emulsifier that can be integrated into cosmetic flacons and that can deliver emulsions on demand by pressing a human fingertip onto a part of the flacon. Standardized cosmetic flacons have been used as basic devices. They consist of two separate glass bottles for two different liquid phases and two mechanical pumps integrated in a multifunctional cap. Regarding the viscosity ranges of the two liquids different microemulsifier structures have been developed. External dimensions and connections of the device have been chosen in a way that allows an integration of the devices into the cap. The second design conists of several streaming paths in parallel that allow a reduction of the pressure drop. Furthermore, it consists of three structured silicon chips bonded together. Emulsions with a stability of about 15-30 min have been achieved without any stabilizers. External forces of less than 10N were sufficient to generate emulsions on demand.

  17. Stabilisation of Emulsions by Trapped Species

    E-print Network

    A. J. Webster; M. E. Cates

    1998-04-28

    We consider an emulsion whose droplets contain a trapped species (insoluble in the continuous phase), and study the emulsion's stability against coarsening via Lifshitz-Slyozov dynamics (Ostwald Ripening). Extending an earlier treatment by Kabalnov et al(Colloids and Surfaces, 24,(1987), 19-32), we derive a general condition on the mean initial droplet volume which ensures stability, even when arbitrary polydispersity is present in both size and composition of the initial droplets. We distinguish "nucleated" coarsening, which requires either fluctuations about the mean field equations or a tail in the initial droplet size distribution, from "spinodal" coarsening in which a typical droplet is locally unstable. A weaker condition for stability, previously suggested by Kabalnov et al., is sufficient only to prevent "spinodal" coarsening and is best viewed as a condition for metastability. The coarsening of unstable emulsions is considered, and shown at long times to resemble that of ordinary emulsions (with no trapped species), but with a reduced value of the initial volume fraction of dispersed phase. We discuss the physical principles relevant to the stability of emulsions with trapped species, describing how these may be exploited to restabilise partially coarsened emulsions and to "shrink" previously formed emulsion droplets to form "miniemulsions".

  18. Performance properties of the emulsion explosive QM-100

    SciTech Connect

    Garza, R.; Helm, F.; Souers, P.C.; Simpson, R.L.

    1992-12-01

    QM-100 was evaluated in cylinder expansion configuration to determine the detonation production equation of state. Two experiments were run. No differences in scaled cylinder wall expansions could be determined; hence, despite a diameter effect on detonation velocity, metal acceleration was the same for both experiments. Max expansion volumes were limited, {approximately} 4 V/V{sub o}. This was interpreted to be result of significant inhomogeneities in the emulsion explosive fills which in turn produced a nonuniform detonation and ruptured the cylinders. 7 refs., 6 figs., 4 tabs.

  19. Performance properties of the emulsion explosive QM-100

    SciTech Connect

    Garza, R.; Helm, F.; Souers, P.C.; Simpson, R.L.

    1992-12-01

    QM-100 was evaluated in cylinder expansion configuration to determine the detonation production equation of state. Two experiments were run. No differences in scaled cylinder wall expansions could be determined; hence, despite a diameter effect on detonation velocity, metal acceleration was the same for both experiments. Max expansion volumes were limited, [approximately] 4 V/V[sub o]. This was interpreted to be result of significant inhomogeneities in the emulsion explosive fills which in turn produced a nonuniform detonation and ruptured the cylinders. 7 refs., 6 figs., 4 tabs.

  20. Development and Assessment of Oil-in-Water Emulsions for Encapsulation of Reactive Iron Particles for Subsurface Delivery

    NASA Astrophysics Data System (ADS)

    Berge, N. D.; Taghavy, A.; Ramsburg, A.

    2007-12-01

    Reactive iron particles hold promise for use in the destruction of contaminants in the subsurface environment. Application of these nano- to submicron-scale particles, however, may be limited by poor subsurface transport and non-uniform distribution of the reactive material. Delivery issues are particularly important when evaluating the efficacy of iron-based technologies for treatment of dense non-aqueous phase liquid (DNAPL) source zones. Current approaches for the delivery of reactive iron particles within DNAPL source zones are hindered by particle agglomeration, flow bypassing, and presence of non-target reactions. Encapsulation of the reactive particles within an oil-in-water emulsion is a novel approach that may overcome these limitations. Development of kinetically-stable, iron-laden, oil-in-water emulsions commenced by identifying surfactant-based coatings to increase the stability of commercially-available iron particles within non-polar organic phases (e.g., soy oil). A phase inversion technique was employed to disperse approximately 10% wt of the iron-laden, organic phase within a continuous aqueous phase containing nonionic emulsifiers. Emulsions were designed to ensure emulsifier proportions yielded hydrophilic-lipophilic balances affiliated with oil-in-water emulsions. Micrographs of the oil-in-water emulsions suggest that the average diameter of the oil droplets is approximately one micrometer. The presence of iron within oil droplets was confirmed in the micrographs and supported by an absence of iron agglomeration within the continuous phase. Bulk characteristics of each emulsion (density and viscosity) were used in conjunction with interfacial tension measurements in total trapping number analyses to assess the propensity of these emulsions to mobilize an entrapped trichloroethene (TCE)-DNAPL. Results suggest that the emulsions described herein should not cause significant mobilization of entrapped TCE-DNAPL in fine-to-medium grain sandy media. Column experiments are being conducted to evaluate the transport of these emulsions through sandy media. Preliminary results from experiments with iron-free emulsions suggest conductivity reductions occurring during emulsion flushing are not the result of extensive pore-clogging but rather are due to viscosity changes (emulsion viscosities range from 2 to 10 cP). Current efforts are focused on assessing and comparing both transport and reaction of commercially available iron particles and iron-laden emulsions within sandy porous media.

  1. The stability behavior of sol-emulsion systems

    SciTech Connect

    Sunkel, J.M.; Berg, J.C. [Univ. of Washington, Seattle, WA (United States). Dept. of Chemical Engineering] [Univ. of Washington, Seattle, WA (United States). Dept. of Chemical Engineering

    1996-05-10

    Sol-emulsion systems, i.e., colloids consisting of mixed populations of solid particles and emulsion droplets, are encountered in a number of applications, e.g., oil-assisted agglomeration for particle removal (coal fines from water). The stability characteristics of mixed aqueous dispersions of titanium dioxide and mineral oil emulsion droplets are examined as a function of pH and emulsifier type and content. Zeta potentials of both the titanium dioxide and the mineral oil particles are measured under all conditions to identify regions of expected heterocoagulation and to quantify the electrostatic boundary conditions. The latter are used in the numerical solution of the pair interaction potentials based on the recent theory of McCormack et al. The potential functions are used in a modified version of the stability model of Hogg, Healy, and Fuerstenau to calculate early-stage aggregation rates. Photon correlation spectroscopy is used to determine stability ratios for homo- and heterocoagulation, and initial results indicate good agreement between experiments and computations.

  2. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the emulsion crumb rubber subcategory. 428...MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428...Applicability; description of the emulsion crumb rubber subcategory....

  3. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Applicability; description of the emulsion crumb rubber subcategory. 428...MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428...Applicability; description of the emulsion crumb rubber subcategory....

  4. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the emulsion crumb rubber subcategory. 428...MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428...Applicability; description of the emulsion crumb rubber subcategory....

  5. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the emulsion crumb rubber subcategory. 428...MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428...Applicability; description of the emulsion crumb rubber subcategory....

  6. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability; description of the emulsion crumb rubber subcategory. 428...MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428...Applicability; description of the emulsion crumb rubber subcategory....

  7. Directional Search for Isospin-Violating Dark Matter with Nuclear Emulsion

    E-print Network

    Keiko I. Nagao; Tatsuhiro Naka

    2012-05-22

    Some of direct dark matter searches reported not only positive signals but also annual modulation of the signal event. However, the parameter spaces have been excluded by other experiments. Isospin violating dark matter solves the contradiction by supposing different coupling to proton and neutron. We study the possibility to test the favored parameter region by isospin violating dark matter model with the future detector of dark matter using the nuclear emulsion. Since the nuclear emulsion detector has directional sensitivity, the detector is expected to examine whether the annual modulations observed other experiments is caused by dark matter or background signals.

  8. Improved viscosity-concentration equation for emulsions of nearly spherical droplets

    E-print Network

    Carlos I. Mendoza; I. Santamaria-Holek

    2009-03-31

    We propose an improved viscosity model accounting for experiments of emulsions of two immiscible liquids at arbitrary volume fractions and low shear rates. The model is based on a recursive-differential method formulated in terms of the appropriate scaling variable which emerges from an analysis of excluded volume effects in the system. This variable, called the effective filling fraction, incorporates the geometrical information of the system which determines the maximum packing and reduces to the bare filling fraction for infinitely diluted emulsions. The agreement of our model for the viscosity with experiments is remarkable for all the range of volume fractions and viscosity ratio.

  9. Bond Graph Modeling and Validation of an Energy Regenerative System for Emulsion Pump Tests

    PubMed Central

    Li, Yilei; Zhu, Zhencai; Chen, Guoan

    2014-01-01

    The test system for emulsion pump is facing serious challenges due to its huge energy consumption and waste nowadays. To settle this energy issue, a novel energy regenerative system (ERS) for emulsion pump tests is briefly introduced at first. Modeling such an ERS of multienergy domains needs a unified and systematic approach. Bond graph modeling is well suited for this task. The bond graph model of this ERS is developed by first considering the separate components before assembling them together and so is the state-space equation. Both numerical simulation and experiments are carried out to validate the bond graph model of this ERS. Moreover the simulation and experiments results show that this ERS not only satisfies the test requirements, but also could save at least 25% of energy consumption as compared to the original test system, demonstrating that it is a promising method of energy regeneration for emulsion pump tests. PMID:24967428

  10. Bond graph modeling and validation of an energy regenerative system for emulsion pump tests.

    PubMed

    Li, Yilei; Zhu, Zhencai; Chen, Guoan

    2014-01-01

    The test system for emulsion pump is facing serious challenges due to its huge energy consumption and waste nowadays. To settle this energy issue, a novel energy regenerative system (ERS) for emulsion pump tests is briefly introduced at first. Modeling such an ERS of multienergy domains needs a unified and systematic approach. Bond graph modeling is well suited for this task. The bond graph model of this ERS is developed by first considering the separate components before assembling them together and so is the state-space equation. Both numerical simulation and experiments are carried out to validate the bond graph model of this ERS. Moreover the simulation and experiments results show that this ERS not only satisfies the test requirements, but also could save at least 25% of energy consumption as compared to the original test system, demonstrating that it is a promising method of energy regeneration for emulsion pump tests. PMID:24967428

  11. Study of v interactions and background estimation in the OPERA emulsion film detector

    E-print Network

    Janicskó-Csáthy, József

    The OPERA (Oscillation Project with Emulsion tRacking Apparatus ) experiment or CNGS1 was approved in 2001 by CERN and presently is under construction. Data-taking is expected to start in 2006. The experiment is designated to the ?? ? ?? oscillation search. OPERA is a hybrid detector comprising a number of electronic detectors and a specially designed nuclear emulsion stack interlaced with lead plates. The total target mass of the detector will be about 1.8 kt. This impressive mass needed for neutrino detection is combined with an even more impressive spatial resolution of about a m , characteristic of the nuclear emulsion technique. The detection of ?? is based on the observation of the decay of the ? lepton. The fine grained structure of nuclear emulsions offers the possibility to directly observe such a decay and by the means of kinematical analysis can be clearly separated from background events. Nuclear emulsions will be produced and processed in industrial quantities and the readout will be don...

  12. Biomedical Applications of Emulsion Templated Scaffolds

    E-print Network

    Moglia, Robert Scott

    2014-03-28

    . To this end, we have utilized emulsion templating to create injectable polyHIPE scaffolds that are biodegradable, highly porous, polymerize at body temperature, and possess appropriate and tunable mechanical properties for tissue regeneration. Poly...

  13. Aging properties of Kodak type 101 emulsions

    NASA Technical Reports Server (NTRS)

    Dohne, B.; Feldman, U.; Neupert, W.

    1984-01-01

    Aging tests for several batches of Kodak type 101 emulsion show that storage conditions significantly influence how well the film will maintain its sensitometric properties, with sensitivity and density increasing to a maximum during this period. Any further aging may result in higher fog levels and sensitivity loss. It is noted that storage in an environment free of photographically active compounds allows film property optimization, and that film batches with different sensitivities age differently. Emulsions with maximum 1700-A sensitivity are 2.5 times faster than those at the low end of the sensitivity scale. These sensitive emulsions exhibit significantly accelerated changes in aging properties. Their use in space applications requires careful consideration of time and temperature profiles, encouraging the use of less sensitive emulsions when the controllability of these factors is limited.

  14. Multi-body coalescence in Pickering emulsions.

    PubMed

    Wu, Tong; Wang, Haitao; Jing, Benxin; Liu, Fang; Burns, Peter C; Na, Chongzheng

    2015-01-01

    Particle-stabilized Pickering emulsions have shown unusual behaviours such as the formation of non-spherical droplets and the sudden halt of coalescence between individual droplets. Here we report another unusual behaviour of Pickering emulsions-the simultaneous coalescence of multiple droplets in a single event. Using latex particles, silica particles and carbon nanotubes as model stabilizers, we show that multi-body coalescence can occur in both water-in-oil and oil-in-water emulsions. The number of droplets involved in the nth coalscence event equals four times the corresponding number of the tetrahedral sequence in close packing. Furthermore, coalescence is promoted by repulsive latex and silica particles but inhibited by attractive carbon nanotubes. The revelation of multi-body coalescence is expected to help better understand Pickering emulsions in natural systems and improve their designs in engineering applications. PMID:25581366

  15. Multi-body coalescence in Pickering emulsions

    NASA Astrophysics Data System (ADS)

    Wu, Tong; Wang, Haitao; Jing, Benxin; Liu, Fang; Burns, Peter C.; Na, Chongzheng

    2015-01-01

    Particle-stabilized Pickering emulsions have shown unusual behaviours such as the formation of non-spherical droplets and the sudden halt of coalescence between individual droplets. Here we report another unusual behaviour of Pickering emulsions—the simultaneous coalescence of multiple droplets in a single event. Using latex particles, silica particles and carbon nanotubes as model stabilizers, we show that multi-body coalescence can occur in both water-in-oil and oil-in-water emulsions. The number of droplets involved in the nth coalscence event equals four times the corresponding number of the tetrahedral sequence in close packing. Furthermore, coalescence is promoted by repulsive latex and silica particles but inhibited by attractive carbon nanotubes. The revelation of multi-body coalescence is expected to help better understand Pickering emulsions in natural systems and improve their designs in engineering applications.

  16. Preparation of stable crude oil transport emulsions

    SciTech Connect

    Gregoli, A.A.; Hamshar, J.A.; Olah, A.M.; Riley, C.J.; Rimmer, D.P.

    1988-02-16

    A process for preparing an oil-in-water emulsion for pipeline transmission is described comprising: (a) shearing and mixing statically, without any dynamic shearing and mixing preceding or following the shearing and mixing statically, a hydrocarbon with an emulsifying composition comprising water and a minor amount of an emulsifying agent at a temperature of from about 100/sup 0/F. to about 200/sup 0/F. to form an oil-in-water emulsion having a viscosity sufficiently low for pipeline transmission, wherein the amount of water in the oil-in-water emulsion is from about 15% to about 60% by weight, and wherein the emulsifying agent is used in an amount sufficient to assist in the formation of the oil-in-water emulsion that is sufficiently stable for pipeline transmission; and wherein the emulsifying agent comprises about 50 percent by weight of an ethoxylated nonyl phenol compound.

  17. The Use of Fish Oil Lipid Emulsion in the Treatment of Intestinal Failure Associated Liver Disease (IFALD)

    PubMed Central

    Chang, Melissa I.; Puder, Mark; Gura, Kathleen M.

    2012-01-01

    Since 2004, fish oil based lipid emulsions have been used in the treatment of intestinal failure associated liver disease, with a noticeable impact on decreasing the incidence of morbidity and mortality of this often fatal condition. With this new therapy, however, different approaches have emerged as well as concerns about potential risks with using fish oil as a monotherapy. This review will discuss the experience to date with this lipid emulsion along with the rational for its use, controversies and concerns. PMID:23363993

  18. Degradation of an aminosilicone polymer in a water emulsion by the Fenton and the photochemically enhanced Fenton reactions

    Microsoft Academic Search

    Antonio Carlos S. C. Teixeira; Roberto Guardani; André M. Braun; Esther Oliveros; Claudio A. O. Nascimento

    2005-01-01

    The degradation of a biologically persistent aminosilicone polymer (PDMAS) formulation, used in the textile industry as a softener of polyester fabrics, was investigated using the Fenton and the photochemically enhanced Fenton reactions. Experiments were performed using a commercially available aqueous silicone formulation (polymer-in-water emulsion stabilized by non-ionic surfactants). Emulsions containing a high PDMAS concentration (typical of textile processing) and a

  19. Surfactant-enhanced cellulose nanocrystal Pickering emulsions.

    PubMed

    Hu, Zhen; Ballinger, Sarah; Pelton, Robert; Cranston, Emily D

    2015-02-01

    The effect of surfactants on the properties of Pickering emulsions stabilized by cellulose nanocrystals (CNCs) was investigated. Electrophoretic mobility, interfacial tension, confocal microscopy and three-phase contact angle measurements were used to elucidate the interactions between anionic CNCs and cationic alkyl ammonium surfactants didecyldimethylammonium bromide (DMAB) and cetyltrimethylammonium bromide (CTAB). Both surfactants were found to adsorb onto CNCs with concentration-dependent morphology. At low concentrations, individual surfactant molecules adsorbed with alkyl tails pointing outward leading to hydrophobic CNCs. At higher concentrations, above the surfactant's apparent critical micelle concentration, surfactant aggregate morphologies on CNCs were inferred and the hydrophobicity of CNCs decreased. DMAB, which has two alkyl tails, rendered the CNCs more hydrophobic than CTAB which has only a single alkyl tail, at all surfactant concentrations. The change in CNC wettability from surfactant adsorption was directly linked to emulsion properties; adding surfactant increased the emulsion stability, decreased the droplet size, and controlled the internal phase of CNC Pickering emulsions. More specifically, a double transitional phase inversion, from oil-in-water to water-in-oil and back to oil-in-water, was observed for emulsions with CNCs and increasing amounts of DMAB (the more hydrophobic surfactant). With CNCs and CTAB, no phase inversion was induced. This work represents the first report of CNC Pickering emulsions with surfactants as well as the first CNC Pickering emulsions that can be phase inverted. The ability to surface modify CNCs in situ and tailor emulsions by adding surfactants may extend the potential of CNCs to new liquid formulations and extruded/spray-dried materials. PMID:25463186

  20. Osmotic Stabilisation of Concentrated Emulsions and Foams

    E-print Network

    A. J. Webster; M. E. Cates

    2001-01-19

    In the absence of coalescence, coarsening of emulsions (and foams) is controlled by molecular diffusion of dispersed phase between droplets/bubbles. Studies of dilute emulsions have shown how the osmotic pressure of a trapped species within droplets can ``osmotically stabilise'' the emulsion. Webster and Cates (Langmuir, 1998, 14, 2068-2079) gave rigorous criteria for osmotic stabilisation of mono- and polydisperse emulsions, in the dilute regime. We consider here whether analogous criteria exist for the osmotic stabilisation of mono- and polydisperse concentrated emulsions and foams, and suggest that the pressure differences driving coarsening are small compared to the mean Laplace pressure. An exact calculation confirms this for a monodisperse 2D model, finding a bubble's pressure as P_i = P + Pi + P_i^G, with P, Pi the atmospheric and osmotic pressures, and P_i^G a ``geometric pressure'' that reduces to the Laplace pressure only for a spherical bubble. For Princen's 2D emulsion model, P_i^G is only 5% larger in the dry limit than the dilute limit. We conclude that osmotic stabilisation of dense systems typically requires a pressure of trapped molecules in each droplet that is comparable to the Laplace pressures the same droplets would have if spherical, as opposed to the much larger Laplace pressures present in the system. We study coarsening of foams and concentrated emulsions when there is insufficient of the trapped species present. Rate-limiting mechanisms are considered, their applicability and associated droplet growth rates discussed. In a concentrated foam or emulsion, a finite yield threshold for droplet rearrangement may be enough to prevent coarsening of the remainder.

  1. Results from JACEE and EMU05

    NASA Astrophysics Data System (ADS)

    Takahashi, Yoshiyuki

    1993-06-01

    Energy spectra of high energy cosmic ray nuclei and interaction studies from JACEE experiments are described with a particular emphasis on the energy region close to the ``Knee'' (100-1000 TeV/nucleus) and high density nucleus-nucleus interactions. Heavy ion studies with a magnetic emulsion chamber with accelerator beams (EMU05 experiments) are also discussed to illustrate some outstanding issues on high and low PT phenomena and on isospin symmetries.

  2. A model for the prediction of droplet size in Pickering emulsions stabilized by oppositely charged particles.

    PubMed

    Nallamilli, Trivikram; Mani, Ethayaraja; Basavaraj, Madivala G

    2014-08-12

    Colloidal particles irreversibly adsorb at fluid-fluid interfaces stabilizing what are commonly called "Pickering" emulsions and foams. A simple geometrical model, the limited coalescence model, was earlier proposed to estimate droplet sizes in emulsions. This model assumes that all of the particles are effective in stabilization. The model predicts that the average emulsion drop size scales inversely with the total number of particles, confirmed qualitatively with experimental data on Pickering emulsions. In recent years, there has been an increasing interest in synthesizing emulsions with oppositely charged particles (OCPs). In our experimental study, we observed that the drop size varies nonmonotonically with the number ratio of oppositely charged colloids, even when a fixed total number concentration of colloids is used, showing a minimum. We develop a mathematical model to predict this dependence of drop size on number ratio in such a mixed particle system. The proposed model is based on the hypothesis that oppositely charged colloids form stable clusters due to the strong electrostatic attraction between them and that these clusters are the effective stabilizing agents. The proposed model is a two-parameter model, parameters being the ratio of effective charge of OCPs (denoted as k) and the size of the aggregate containing X particles formed due to aggregation of OCPs. Because the size of aggregates formed during emulsification is not directly measurable, we use suitable values of parameters k and X to best match the experimental observations. The model predictions are in qualitative agreement with experimentally observed nonmonotonic variation of droplet sizes. Using experiments and theory, we present a physical insight into the formation of OCP stabilized Pickering emulsions. Our model upgrades the existing Wiley's limited coalescence model as applied to emulsions containing a binary mixture of oppositely charged particles. PMID:25054284

  3. Water-in-oil emulsions prepared by peptide-silicone hybrid polymers as active interfacial modifier: effects of silicone oil species on dispersion stability of emulsions.

    PubMed

    Sakai, Kenichi; Iijima, Satoshi; Ikeda, Ryosuke; Endo, Takeshi; Yamazaki, Takahiro; Yamashita, Yuji; Natsuisaka, Makoto; Sakai, Hideki; Abe, Masahiko; Sakamoto, Kazutami

    2013-01-01

    We have recently proposed a new general concept regarding amphiphilic materials that have been named as "active interfacial modifier (AIM)." In emulsion systems, an AIM is essentially insoluble in both water and organic solvents; however, it possesses moieties that are attracted to each of these immiscible liquid phases. Hence, an AIM practically stays just at the interface between the two phases and makes the resulting emulsion stable. In this study, the effects of silicone oil species on the dispersion stability of water-in-oil (W/O) emulsions in the presence of an AIM sample were evaluated in order to understand the destabilization mechanism in such emulsion systems. The AIM sample used in this study is an amphiphilic polymer consisting of a silicone backbone modified with hydrocarbon chains and hydrolyzed silk peptides. The Stokes equation predicts that the sedimentation velocity of water droplets dispersed in a continuous silicone oil phase simply depends on the expression (? - ??)/? assuming that the droplet size is constant (where ? is the density of the dispersed water phase, ?? is the density of the continuous silicone oil phase, and ? is the viscosity of the oil phase). The experimental results shown in this paper are consistent with the Stokes prediction: i.e., in the low-viscous genuine or quasi-Newtonian fluid region, the dispersion stability increases in the following order: dodecamethylpentasiloxane (DPS) < decamethylcyclopentasiloxane (D?) ? dodecamethylcyclohexasiloxane (D?). This order agrees well with the order obtained by using the expression (? - ??)/? as DPS > D? > D?. This indicates that our emulsion system experiences destabilization through sedimentation, but hardly any coalescence occurs owing to the presence of an additional third phase consisting of the AIM that stabilizes the silicone oil/water interface in the emulsions. PMID:23823917

  4. S-190 exposure verification flight test. [photographic emulsions and film

    NASA Technical Reports Server (NTRS)

    Perry, L.

    1973-01-01

    A flight test was conducted to determine the optimum exposures for the Skylab S-190A experiment. An aircraft multispectral photographic system (AMPS) which is installed in the NASA Earth Resources aircraft NP3A was used to simulate the S-190A system. The same film emulsions to be used for S-190A were used in the flight test. These rolls were on factory-loaded spools for use in the AMPS camera system. It was found that some variation is to be expected between these rolls and the S-190A flight loads.

  5. Transport in two dimensional electronic micro-emulsions

    SciTech Connect

    Spivak, Boris [Department of Physics, University of Washington, Seattle, WA 98195 (United States)]. E-mail: spivak@u.washington.edu; Kivelson, Steven A. [Department of Physics, Stanford University, Stanford, CA 94305-4045 (United States)

    2006-09-15

    In two dimensional electron systems with Coulomb or dipolar interactions, a direct transition, whether first or second order, from a liquid to a crystalline state is forbidden. As a result, between these phases there must be other (micro-emulsion) phases which can be viewed as a meso-scale mixture of the liquid and crystalline phases. We investigate the transport properties of these new electronic phases and present arguments that they are responsible for the various transport anomalies that have been seen in experiments on the strongly correlated 2DEG in high mobility semiconductor devices with low electron densities.

  6. The atomization of water-oil emulsions

    SciTech Connect

    Broniarz-Press, L.; Ochowiak, M.; Rozanski, J.; Woziwodzki, S. [Department of Chemical Engineering and Equipment, Faculty of Chemical Technology, Poznan University of Technology, Pl. M. Sklodowskiej-Curie 2, PL 60-965 Poznan (Poland)

    2009-09-15

    The paper presents the results of experimental studies on atomization of the emulsions flowing through twin-fluid atomizers obtained by the use of the digital microphotography method. The main elements of the test installation were: nozzle, reservoir, pump and measurement units of liquid flow. The photographs were taken by a digital camera with automatic flash at exposure time of 1/8000 s and subsequently analyzed using Image Pro-Plus. The oils used were mineral oils 20-90, 20-70, 20-50 and 20-30. The studies were performed at flow rates of liquid phase changed from 0.0014 to 0.011 (dm{sup 3}/s) and gas phase changed from 0.28 to 1.4 (dm{sup 3}/s), respectively. The analysis of photos shows that the droplets being formed during the liquid atomization have very different sizes. The smallest droplets have diameters of the order of 10 {mu}m. The experimental results showed that the changes in physical properties of a liquid phase lead to the significant changes in the spray characteristics. The analysis of the photos of water and emulsions atomization process showed that the droplet sizes are dependent on gas and liquid flow rates, construction of nozzle and properties of liquid. The differences between characteristics of atomization for water and emulsions have been observed. Analysis of photos on forming the droplets in air-water and air-emulsions systems showed that droplets are bigger in air-emulsion system (at the same value of gas to liquid mass ratio). The values of Sauter mean diameter (SMD) increased with increase of volume fraction of oil in emulsion. The droplet size increased with emulsion viscosity. (author)

  7. Shock Compression and Recovery of Microorganism-Loaded Broths and AN Emulsion

    NASA Astrophysics Data System (ADS)

    Hazell, P. J.; Beveridge, C.; Groves, K.; Stennett, C.

    2009-12-01

    The microorganisms Escherichia coli, Enterococcus faecalis and Zygosaccharomyces bailii and an oil-based emulsion, have been subjected to shock compression using the flyer-plate technique to initial pressures of 0.8 GPa (in the suspension). In each experiment, a stainless steel capsule was used to contain the broths and allow for recovery without contamination. Where cavitation was mostly suppressed by virtue of simultaneous shock and dynamic compression, no kill was observed. By introducing an air gap behind the suspension, limited kill was measured in the yeast. Results also suggest that stable emulsification occurs in coarse oil-based emulsions that are subjected to shock.

  8. Factors affecting the emulsifying and rheological properties of gum acacia in beverage emulsions

    Microsoft Academic Search

    R. A Buffo; G. A Reineccius; G. W Oehlert

    2001-01-01

    Gum acacia, a natural hydrocolloid, is extensively used as an emulsifier\\/stabilizer in beverage emulsions. Factors that may affect emulsion formation, emulsion stability and viscosity of the emulsion concentrate were studied to assess their significance, including proximal composition of the gum (protein content and mineral content), gum processing prior to emulsion preparation (pasteurization and demineralization), and pH of the dilute emulsion.

  9. Future Experiments with HADES at FAIR

    SciTech Connect

    Tlusty, P. [Nuclear Physics Institute, Academy of Sciences of Czech Republic, 25068 Rez (Czech Republic)

    2010-12-28

    The Dielectron Spectrometer HADES installed at GSI Darmstadt recently provided new intriguing results on production of electron pairs and strangeness from elementary and nucleus-nucleus collisions. The obtained data call for further systematic investigations of heavier systems and/or at higher energies.For this purpose, the HADES spectrometer has been upgraded with a high-granularity RPC time-of-flight wall. In addition, a completely new detector read-out and data-acquisition system has been implemented which will greatly improve our data-taking rates. We describe the current status of the HADES spectrometer and our plans for experiments on heavy system collisions at energies up to 10 A GeV on the upcoming FAIR facility.

  10. Annatto Polymeric Microparticles: Natural Product Encapsulation by the Emulsion-Solvent Evaporation Method

    ERIC Educational Resources Information Center

    Teixeira, Zaine; Duran, Nelson; Guterres, Silvia S.

    2008-01-01

    In this experiment, the extract from annatto seeds was encapsulated in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) particles by the emulsion-solvent evaporation method. The particles were washed and centrifuged to remove excess stabilizer and then freeze-dried. The main compound of annatto seeds, bixin, has antioxidant properties as well…

  11. Optical transmission measurements for in-line monitoring of turbid oil-water emulsions

    NASA Astrophysics Data System (ADS)

    Metz, Philipp; Dopf, Katja; Aichholz, Markus; Riedel, Boris; Lemmer, Uli; Freudig, Barbara; Zimmermann, Clifton; Gerken, Martina

    2014-05-01

    For absorbing media the concentration may be calculated directly from the optical transmission following the logarithmic dependence given in the Lambert-Beer law. Due to multiple scattering events in oil-water emulsions (e.g. milk, cream, etc.), these exhibit a nonlinear relationship between the attenuation and the oil concentration. We demonstrate that for increasing oil content in oil-water emulsions the attenuation first increases, then levels out, and finally even decreases for a fat content of 60%. Single-wavelength optical transmission measurements are found to be well suited for the in-line monitoring of oil-water emulsions of fat contents below 20%, e.g., for the in-line fat content monitoring of milk. Using experiments and ray-tracing simulations we evaluate system optimization.

  12. Analysis of the invert emulsion oil mud-polycrystalline diamond bit system in shallow permeable formations

    SciTech Connect

    Golis, S.W.

    1983-02-01

    Recent field experience with shallow, normal pressured wells in South Texas demonstrated an invert emulsion oil mud employed with a polycrystalline diamond compact (PDC) bit significantly increased PDC bit rate of penetration (ROP) and life. Each well used an invert emulsion oil mud from surface casing to total depth and a PDC bit to drill the majority of the same interval. This resulted in substantial cost savings compared to KCl/polymer and freshwater mud systems. To realize the full cost savings potential, hydraulics and mud programs were designed to maximize PDC bit performance and minimize oil mud costs. This paper examines field results and develops a correlation between hydraulics and mud programs and optimum invert emulsion oil mud-PDC bit performance.

  13. 21 CFR 524.802 - Enrofloxacin, silver sulfadiazine emulsion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Enrofloxacin, silver sulfadiazine emulsion. 524.802 Section 524.802 Food and Drugs FOOD...ANIMAL DRUGS § 524.802 Enrofloxacin, silver sulfadiazine emulsion. (a) Specifications . Each milliliter contains 5...

  14. Jamming transition in emulsions and granular materials.

    PubMed

    Zhang, H P; Makse, H A

    2005-07-01

    We investigate the jamming transition in packings of emulsions and granular materials via molecular dynamics simulations. The emulsion model is composed of frictionless droplets interacting via nonlinear normal forces obtained using experimental data acquired by confocal microscopy of compressed emulsions systems. Granular materials are modeled by Hertz-Mindlin deformable spherical grains with Coulomb friction. In both cases, we find power-law scaling for the vanishing of pressure and excess number of contacts as the system approaches the jamming transition from high volume fractions. We find that the construction history parametrized by the compression rate during the preparation protocol has a strong effect on the micromechanical properties of granular materials but not on emulsions. This leads the granular system to jam at different volume fractions depending on the histories. Isostaticity is found in the packings close to the jamming transition in emulsions and in granular materials at slow compression rates and infinite friction. Heterogeneity of interparticle forces increases as the packings approach the jamming transition which is demonstrated by the exponential tail in force distributions and the small values of the participation number measuring spatial localization of the forces. However, no signatures of the jamming transition are observed in structural properties, like the radial distribution functions and the distributions of contacts. PMID:16089950

  15. High pressure-resistant nonincendive emulsion explosive

    DOEpatents

    Ruhe, Thomas C. (Duquesne, PA); Rao, Pilaka P. (Baghlingampalli, IN)

    1994-01-01

    An improved emulsion explosive composition including hollow microspheres/bulking agents having high density and high strength. The hollow microspheres/bulking agents have true particle densities of about 0.2 grams per cubic centimeter or greater and include glass, siliceous, ceramic and synthetic resin microspheres, expanded minerals, and mixtures thereof. The preferred weight percentage of hollow microspheres/bulking agents in the composition ranges from 3.0 to 10.0 A chlorinated paraffin oil, also present in the improved emulsion explosive composition, imparts a higher film strength to the oil phase in the emulsion. The emulsion is rendered nonincendive by the production of sodium chloride in situ via the decomposition of sodium nitrate, a chlorinated paraffin oil, and sodium perchlorate. The air-gap sensitivity is improved by the in situ formation of monomethylamine perchlorate from dissolved monomethylamine nitrate and sodium perchlorate. The emulsion explosive composition can withstand static pressures to 139 bars and dynamic pressure loads on the order of 567 bars.

  16. Particle control of emulsion by membrane emulsification and its applications

    Microsoft Academic Search

    Tadao Nakashima; Masataka Shimizu; Masato Kukizaki

    2000-01-01

    Particle-size control of emulsion is very important for maintaining stability and giving emulsions new functional roles. Porous glass membrane, prepared by phase separation of a glass composition, is available as an emulsifying element, from which, one can obtain monodispersed emulsion with different particle sizes, and useful water\\/oil\\/water (W\\/O\\/W) emulsion in very high yield. The authors have called this new technology

  17. Asphaltene and solids-stabilized water-in-oil emulsions

    Microsoft Academic Search

    Danuta M. Sztukowski

    2005-01-01

    Water-in-crude oil emulsions are a problem in crude oil production, transportation, and processing. Many of these emulsions are stabilized by asphaltenes and native oilfield solids adsorbed at the oil-water interface. Design of effective emulsion treatments is hampered because there is a lack of understanding of the role asphaltenes and solids play in stabilizing these emulsions. In this work, the structural,

  18. Combustion Study of Stabilized Water-in-Diesel Fuel Emulsion

    Microsoft Academic Search

    M. Y. E. Selim; M. T. Ghannam

    2009-01-01

    An experimental investigation has been carried out to produce a stable diesel\\/water emulsion fuel and use it in a diesel engine under different operating and design conditions. The emulsion stayed stable for up to 30% water in diesel for up to one week and 20% water in diesel for four weeks. The physical properties of the stable W\\/D emulsions in

  19. Janus-like Pickering emulsions and their controllable coalescence.

    PubMed

    Xu, Jie; Ma, Aijing; Liu, Tianqing; Lu, Chunli; Wang, Dayang; Xu, Haolan

    2013-11-28

    Janus-like emulsions stabilized by OH(-) and polydopamine (PDA) particles were realized. The OH(-) and particle occupied areas on emulsion droplet surfaces are spatially separated. Via controlling the pH and ionic strength, the coalescence of Janus-like emulsion droplets could be manipulated. PMID:24129678

  20. A `granocentric' model for random packing of jammed emulsions

    E-print Network

    Weeks, Eric R.

    LETTERS A `granocentric' model for random packing of jammed emulsions Maxime Clusel1 *, Eric I of polydisperse emulsion droplets to build a simple statistical model in which the com- plexity of the global' view captures the properties of the polydisperse emulsion packing--ranging from the microscopic

  1. Homogenization of two phase emulsions with surface tension eects

    E-print Network

    Homogenization of two phase emulsions with surface tension eects Robert Lipton and Bogdan Vernescu Key words: homogenization, emulsions, surface tension, eective viscos- ity, bounds Abstract We consider an emulsion of two Stokes uids, one of which is peri- odically distributed in the form of small

  2. Polymersomes Fabrication of Polymersomes using Double-Emulsion

    E-print Network

    Polymersomes Fabrication of Polymersomes using Double-Emulsion Templates in Glass-Coated Stamped-stabilized water/organic solvent/water (W/O/W) double emulsions in microfluidic devices.[10,11] The assembly of the copolymers is directed by the double-emulsion droplets during evaporation of the organic solvent in which

  3. Polymeric Stabilized Emulsions: Steric Effects and Deformation in Soft Systems

    E-print Network

    Chan, Derek Y C

    Polymeric Stabilized Emulsions: Steric Effects and Deformation in Soft Systems Ofer Manor,,,¶ Thanh is appreciable, that the stability of emulsion drops is less sensitive to the molecular weight or size used to control emulsion and foam stability.1,2 An understanding of the underlying stabilizing

  4. Homogenization of two phase emulsions with surface tension effects

    E-print Network

    Homogenization of two phase emulsions with surface tension effects Robert Lipton \\Lambda and Bogdan Institute Rd., Worcester MA 01609 Key words: homogenization, emulsions, surface tension, effective viscos­ ity, bounds Abstract We consider an emulsion of two Stokes fluids, one of which is peri­ odically

  5. Magnetoresistive Emulsion Analyzer Gungun Lin1,2

    E-print Network

    Cuniberti, Gianaurelio

    and magnetic content of the emulsion. Our method offers important complementarity to conventional optical, manipulate, and sort objects, e.g. liposome capsules or emulsions containing known doses of magnetic-activated cell sorting (FACS) techniques10 . Here and for the first time, a magnetic emulsion analyzer capable

  6. Method for selective plugging using resin emulsions

    SciTech Connect

    Friedman, R.H.

    1982-10-05

    Methods and compositions are provided for selectively plugging the water-rich strata of subterranean formations, including injection into the formation of a water-insoluble, oil-soluble resin emulsion. A series of chemical reactions is initiated insitu such that the emulsion demulsifies, resulting in the coalescence of resin droplets. The coalesced water-insoluble, oil-soluble resin droplets are effective to selectively plug the water-rich strata over a relatively long distance and over a relatively long period of time.

  7. Mixed O/W emulsions stabilized by solid particles: a model system for controlled mass transfer triggered by surfactant addition.

    PubMed

    Drelich, Audrey; Grossiord, Jean-Louis; Gomez, François; Clausse, Danièle; Pezron, Isabelle

    2012-11-15

    This article deals with a model mixed oil-in-water (O/W) emulsion system developed to study the effect of surfactants on mass transfer between dispersed oil droplets of different composition. In this purpose, our goal was to formulate O/W emulsions without any surface active agents as stabilizer, which was achieved by replacing surfactants by a mixture of hydrophilic/hydrophobic silica particles. Then, to study the specific role of surfactants in the oil transfer process, different types and concentrations of surfactants were added to the mixed emulsion after its preparation. In such a way, the same original emulsion can be used for all experiments and the influence of various surface active molecules on the oil transfer mechanism can be directly studied. The model mixed emulsion used consists of a mixture of hexadecane-in-water and tetradecane-in-water emulsions. The transfer between tetradecane and hexadecane droplets was monitored by using differential scanning calorimetry, which allows the detection of freezing and melting signals characteristic of the composition of the dispersed oil droplets. The results obtained showed that it is possible to trigger the transfer of tetradecane towards hexadecane droplets by adding surfactants at concentrations above their critical micellar concentration, measured in presence of solid particles, through micellar transport mechanism. PMID:22909967

  8. Pipeline flow of unstable and surfactant-stabilized emulsions

    SciTech Connect

    Pal, R. (Univ. of Waterloo, Ontario (Canada). Dept. of Chemical Engineering)

    1993-11-01

    The literature available on pipeline flow behavior of emulsions is reviewed critically. New results concerning the laminar and turbulent flow behaviors of unstable (without any added surfactant) and surfactant-stabilized water-in-oil emulsions are presented. The unstable emulsions exhibit drag reduction behavior in turbulent flow; the measured friction factors fall well below the values expected on the basis of the laminar flow properties. Unstable water-in-oil emulsions exhibit much stronger drag reduction activity than the unstable oil-in-water emulsions. The drag reduction activity diminishes (in some cases vanishes completely) upon the addition of a surfactant to the system.

  9. Electrical properties of chain microstructure magnetic emulsions in magnetic field

    E-print Network

    Arthur Zakinyan; Yuri Dikansky; Marita Bedzhanyan

    2014-02-05

    The work deals with the experimental study of the emulsion whose dispersion medium is a magnetic fluid while the disperse phase is formed by a glycerin-water mixture. It is demonstrated that under effect of a magnetic field chain aggregates form from the disperse phase drops. Such emulsion microstructure change affects its macroscopic properties. The emulsion dielectric permeability and specific electrical conductivity have been measured. It is demonstrated that under the effect of relatively weak external magnetic fields (~ 1 kA/m) the emulsion electrical parameters may change several fold. The work theoretically analyzes the discovered regularities of the emulsion electrical properties.

  10. Emulsion stability of cosmetic creams based on water-in-oil high internal phase emulsions

    Microsoft Academic Search

    Chan Ik Park; Wan-Gu Cho; Seong Jae Lee

    2003-01-01

    The emulsion stability of cosmetic creams based on the water-in-oil (W\\/O) high internal phase emulsions (HIPEs) containing water, squalane oil and cetyl dimethicone copolyol was investigated with various com- positional changes, such as electrolyte concentration, oil polarity and water phase volume fraction. The rheological consistency was mainly destroyed by the coalescence of the deformed water droplets. The slope change of

  11. Emulsions stabilised by whey protein microgel particles: towards food-grade Pickering emulsions.

    PubMed

    Destribats, Mathieu; Rouvet, Martine; Gehin-Delval, Cécile; Schmitt, Christophe; Binks, Bernard P

    2014-09-28

    We have investigated a new class of food-grade particles, whey protein microgels, as stabilisers of triglyceride-water emulsions. The sub-micron particles stabilized oil-in-water emulsions at all pH with and without salt. All emulsions creamed but exhibited exceptional resistance to coalescence. Clear correlations exist between the properties of the microgels in aqueous dispersion and the resulting emulsion characteristics. For conditions in which the particles were uncharged, fluid emulsions with relatively large drops were stabilised, whereas emulsions stabilized by charged particles contained smaller flocculated drops. A combination of optical microscopy of the drops and spectrophotometry of the resolved aqueous phase allowed us to estimate the interfacial adsorption densities of the particles using the phenomenon of limited coalescence. We deduce two classes of particle arrangement. Complete adsorption of the particles was obtained when they were neutral or when their charges were screened by salt resulting in at least one particle monolayer at the interface. By contrast, only around 50% of the particles adsorbed when they were charged with emulsion drops being covered by less than half a monolayer. These findings were supported by direct visualization of drop interfaces using cryo-scanning electron microscopy. Uncharged particles were highly aggregated and formed a continuous 2-D network at the interface. Otherwise particles organized as individual aggregates separated by particle-free regions. In this case, we suggest that some particles spread at the interface leading to the formation of a continuous protein membrane. Charged particles displayed the ability to bridge opposing interfaces of neighbouring drops to form dense particle disks protecting drops against coalescence; this is the main reason for the flocculation and stability of emulsions containing sparsely covered drops. PMID:24675994

  12. Na-caseinate/oil/water systems: emulsion morphology diagrams.

    PubMed

    Tan, Hui Lin; McGrath, Kathryn M

    2012-09-01

    The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network. PMID:22709624

  13. Characteristics of Nano-emulsion for Cold Thermal Storage

    NASA Astrophysics Data System (ADS)

    Fumoto, Koji; Kawaji, Masahiro; Kawanami, Tsuyoshi

    Phase change emulsion (PCE) is novel kind of heat storage and heat transfer fluids. It has characteristics as follows; greater apparent specific heat and higher heat transfer abilities in the phase change temperature range than conventional single phase heat transfer fluid. In this paper, a phase change emulsion, which has droplet diameter distribution of nanometer, were prepared. The Nano-emulsion was formed by low energy emulsification methods, as known the phase inversion temperature (PIT) method. Physical properties, such as viscosity, diameter and its distribution of emulsion were investigated. Especially, the relationships between preparation method and the concentration of surfactant have been discussed in detail. The results show that the viscosity of the Nano-emulsion is lower than the micro-emulsion, which was made by same mixing ratio of surfactant and concentration of phase change material. In addition, the Nano-emulsion clarified that stability was higher than microemulsions.

  14. Modeling of Emulsion Polymerization of Vinyl Chloride

    Microsoft Academic Search

    Klaus Tauer; Gerhard Reinisch; Herbert Gajewski; Ingolf Müller

    1991-01-01

    A survey of the principles of emulsion polymerization modeling of vinyl chloride is presented. Experimental results and model equations for particle nucleation, particle coalescence, and particle growth are discussed. A mechanism for particle coalescence in the course of polymerization is proposed based on the assumption that radical desorption from a particle is the rate-determining step for coalescence. Equations for the

  15. Two remarks on wetting and emulsions

    E-print Network

    Pierre-Gilles de Gennes

    2000-09-18

    This paper is extracted from an opening address given at the workshop "Wetting: from microscopic origins to industrial applications" (Giens, May 6-12, 2000). It discusses two special points a) the nature of line energies for a contact line b) the aging of emulsions.

  16. FOOD EMULSIONS: PRINCIPLES, PRACTICES, AND TECHNIQUES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The newly published book by David Julian McClements entitled, “Food Emulsions: Principles, Practices, and Techniques”, Second edition, was reviewed. The novice entering this field, as well as the expert food scientist, will find this book valuable as specific details throughout the book are referen...

  17. Probing Interfacial Emulsion Stability Controls using Electrorheology

    NASA Astrophysics Data System (ADS)

    Wang, Xiuyu; Brandvik, Amy; Alvarado, Vladimir

    2010-11-01

    The stability of water-in-oil emulsions is controlled by interfacial mechanisms that include oil film rheology of approaching drops and the strength of drop interfaces. Film drainage is mainly a function of the continuous phase rheology. Temperature is used to regulate the viscosity of the continuous phase and hence determine its effect on emulsion stability through film drainage, in contrast with interfacial strength. In this study, one crude oil is used to formulate water-in-oil emulsions. Oil-water interfacial tension is measured to gauge other interfacial changes with temperature. The critical field value, used as proxy of emulsion stability, approaches a plateau value for each crude oil- aqueous solution pair, at sufficiently high temperature (50 ^oC), which is interpreted to reflect the intrinsic drop-coating film resistance to coalescence. Interfacial tension does vary significantly with either aqueous phase composition or temperature. From comparison with previous results, we speculate that drop coating film is composed of a fraction of asphaltic compunds.

  18. Autoxidation of Unsaturated Lipids in Food Emulsion

    Microsoft Academic Search

    Yue-E Sun; Wei-Dong Wang; Hong-Wei Chen; Chao Li

    2011-01-01

    Unsaturated lipids having various physiological roles are of significance in biochemistry, nutrition, medicine, and food. However, the susceptibility of lipids to oxidation is a major cause of quality deterioration in food emulsions. The reaction mechanism and factors that influence oxidation are appreciably different for emulsified lipids and bulk lipids. This article gives a brief overview of the current knowledge on

  19. Plastic flow of foams and emulsions in a channel

    E-print Network

    Dollet, B; Sbragaglia, M

    2014-01-01

    In order to understand the flow profiles of complex fluids, a crucial issue concerns the emergence of spatial correlations among plastic rearrangements exhibiting cooperativity flow behaviour at the macroscopic level. In this paper, the rate of plastic events in a Poiseuille flow is experimentally measured on a confined foam in a Hele-Shaw geometry. The correlation with independently measured velocity profiles is quantified. To go beyond a limitation of the experiments, namely the presence of wall friction which complicates the relation between shear stress and shear rate, we compare the experiments with simulations of emulsion droplets based on the lattice-Boltzmann method, which are performed both with, and without, wall friction. Our results indicate a correlation between the localisation length of the velocity profiles and the localisation length of the number of plastic events. Finally, unprecedented results on the distribution of the orientation of plastic events show that there is a non-trivial correla...

  20. Automatic track recognition for large-angle minimum ionizing particles in nuclear emulsions

    E-print Network

    Fukuda, T; Ishida, H; Matsumoto, T; Matsuo, T; Mikado, S; Nishimura, S; Ogawa, S; Shibuya, H; Sudou, J; Ariga, A; Tufanli, S

    2014-01-01

    We previously developed an automatic track scanning system which enables the detection of large-angle nuclear fragments in the nuclear emulsion films of the OPERA experiment. As a next step, we have investigated this system's track recognition capability for large-angle minimum ionizing particles $(1.0 \\leq |tan \\theta| \\leq 3.5)$. This paper shows that, for such tracks, the system has a detection efficiency of 95$\\%$ or higher and reports the achieved angular accuracy of the automatically recognized tracks. This technology is of general purpose and will likely contribute not only to various analyses in the OPERA experiment, but also to future experiments, e.g. on low-energy neutrino and hadron interactions, or to future research on cosmic rays using nuclear emulsions carried by balloons.

  1. Automatic track recognition for large-angle minimum ionizing particles in nuclear emulsions

    E-print Network

    T. Fukuda; S. Fukunaga; H. Ishida; T. Matsumoto; T. Matsuo; S. Mikado; S. Nishimura; S. Ogawa; H. Shibuya; J. Sudou; A. Ariga; S. Tufanli

    2014-12-19

    We previously developed an automatic track scanning system which enables the detection of large-angle nuclear fragments in the nuclear emulsion films of the OPERA experiment. As a next step, we have investigated this system's track recognition capability for large-angle minimum ionizing particles $(1.0 \\leq |tan \\theta| \\leq 3.5)$. This paper shows that, for such tracks, the system has a detection efficiency of 95$\\%$ or higher and reports the achieved angular accuracy of the automatically recognized tracks. This technology is of general purpose and will likely contribute not only to various analyses in the OPERA experiment, but also to future experiments, e.g. on low-energy neutrino and hadron interactions, or to future research on cosmic rays using nuclear emulsions carried by balloons.

  2. Automatic track recognition for large-angle minimum ionizing particles in nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Fukuda, T.; Fukunaga, S.; Ishida, H.; Matsumoto, T.; Matsuo, T.; Mikado, S.; Nishimura, S.; Ogawa, S.; Shibuya, H.; Sudou, J.; Ariga, A.; Tufanli, S.

    2014-12-01

    We previously developed an automatic track scanning system which enables the detection of large-angle nuclear fragments in the nuclear emulsion films of the OPERA experiment. As a next step, we have investigated this system's track recognition capability for large-angle minimum ionizing particles (1.0 <= |tan ?| <= 3.5). This paper shows that, for such tracks, the system has a detection efficiency of 95% or higher and reports the achieved angular accuracy of the automatically recognized tracks. This technology is of general purpose and will likely contribute not only to various analyses in the OPERA experiment, but also to future experiments, e.g. on low-energy neutrino and hadron interactions, or to future research on cosmic rays using nuclear emulsions carried by balloons.

  3. Solvent quality as a key factor for shear-induced mixing in biopolymer emulsions

    E-print Network

    Solvent quality as a key factor for shear-induced mixing in biopolymer emulsions Y.A. Antonov a in ternary two-phase biopolymer emulsions. Aqueous emulsions on the basis of two proteins, two of emulsion and phase viscosity ratio (PVR) on the phase behavior and emulsion morphology. The solvent quality

  4. Equilibrium and Nonequilibrium States in Microfluidic Double Emulsions Nicolas Pannacci,1

    E-print Network

    Equilibrium and Nonequilibrium States in Microfluidic Double Emulsions Nicolas Pannacci,1 Henrik.57.jb, 68.05.Cf Double emulsions (i.e., emulsions in which the dis- persed phase is also an emulsion industries [1]. Tradi- tional techniques of production of double emulsions essen- tially consist in mixing

  5. Pickering emulsions: what are the main parameters determining the emulsion type and interfacial properties?

    PubMed

    Destribats, Mathieu; Gineste, Stéphane; Laurichesse, Eric; Tanner, Hugo; Leal-Calderon, Fernando; Héroguez, Valérie; Schmitt, Véronique

    2014-08-12

    We synthesized surface-active lipophilic core-hydrophilic shell latex particles, and we probed their efficiency as emulsion stabilizers. The relative weight percentage of the shell, RS/P, was varied to trigger the balance between lipophilicity and hydrophilicity of the particles. Particle wettability could concomitantly be tuned by the pH of the aqueous phase determining the surface charge. Emulsions covering a wide range of RS/P and pH values were fabricated, and their type, oil-in-water (O/W) or water-in-oil (W/O), and kinetic stability were systematically assessed. By adapting the particle gel trapping technique to pH-variable systems and by exploiting the limited coalescence process, we were able to determine the proportion of oil/water interfacial area, C, covered by the particles as well as their contact angle, ?. All of these data were gathered into a single generic diagram showing good correlation between the emulsion type and the particle contact angle (O/W for ? < 90° and W/O for ? > 90°) in agreement with the empirical Finkle rule. Interestingly, no stable emulsion could be obtained when the wettability was nearly balanced and a "bipolar"-like behavior was observed, with the particles adopting two different contact angles whose average value was close to 90°. For particles such that ? < 90°, O/W emulsions were obtained, and, depending on the pH of the continuous phase, the same type of particles and the same emulsification process led to emulsions characterized either by large drops densely covered by the particles or by small droplets that were weakly covered. The two metastable states were also accessible to emulsions stabilized by particles of variable origins and morphologies, thus proving the generality of our findings. PMID:25055160

  6. A novel approach for fast scanning of nuclear emulsions with continuous motion of the microscope stage

    NASA Astrophysics Data System (ADS)

    Aleksandrov, A.; Tioukov, V.

    2013-08-01

    Nuclear emulsions have been used in particle physics experiments for many decades because of their unique spatial resolution. The use of nuclear emulsions as precise tracking detectors in large experiments has recently been made possible due to advances in the production of emulsion films and to the development of very fast automatic scanning devices. The present scanning speed of the European Scanning System (ESS), which has been developed within the OPERA Collaboration, is about 20 cm2/h. In addition to the scanning of OPERA films, the ESS is used for other applications with ever-growing demands for scanning speed, such as the muon radiography of volcanoes. In order to further increase the scanning speed of the ESS, we are testing a novel approach different from the standard stop-and-go motion of the microscope stage in the horizontal plane. Indeed we perform data acquisition with the stage moving at constant speed, using an objective lens with wide field of view. Unlike the implementation realized in Japan where the movement of objective lens and stage are synchronized to pile up images of the same view in a vertical stack, in this approach only the stage is moving horizontally. Thus images at different depths are not fully overlapped and special care is needed in the reconstruction. This approach can give a substantial increase in the scanning speed, especially for thin emulsion layers and wide field of view. In this paper we demonstrate that, after applying special corrections, the emulsion data quality can be as good as with the standard stop-and-go approach. This technique allows to double the scanning speed of the ESS, bringing it to 40 cm2/h without any hardware modification.

  7. Feasibility of low frequency ultrasound for water removal from crude oil emulsions.

    PubMed

    Antes, Fabiane G; Diehl, Liange O; Pereira, Juliana S F; Guimarães, Regina C L; Guarnieri, Ricardo A; Ferreira, Bianca M S; Dressler, Valderi L; Flores, Erico M M

    2015-07-01

    The feasibility of indirect application of low frequency ultrasound for demulsification of crude oil was investigated without using chemical demulsifiers. Experiments were performed in an ultrasonic bath with frequency of 35kHz. Synthetic emulsions with water content of 12%, 35% and 50% and median of droplet size distribution (DSD), median D(0.5), of 5, 10 and 25?m were prepared from crude oil with API density of 19 (heavy crude oil) and submitted to the proposed ultrasound-assisted demulsification procedure. Experimental conditions as temperature, time of exposition to ultrasound and ultrasonic power were evaluated. Separation of water from crude oil emulsion was observed for all emulsions investigated. Demulsification efficiency up to 65% was obtained for emulsion with 50% of water content and DSD of 10?m. Higher efficiency of demulsification was achieved using US temperature of 45°C and ultrasound power of 160W by 15min. Results obtained in this study showed that ultrasound could be considered a promising technology for industrial crude oil treatment and respective water removal. PMID:25640680

  8. Measurement of $??$ Decay-Simulating Events in Nuclear Emulsion with Molybdenum Filling

    E-print Network

    V. D. Ashitkov; A. S. Barabash; V. Ya. Bradnova; V. A. Ditlov; V. V. Dubinina; N. P. Egorenkova; S. I. Konovalov; E. A. Pozharova; N. G. Polukhina; V. A. Smirnitsky; N. I. Starkov; M. M. Chernyavsky; T. V. Shchedrina; V. I. Umatov

    2011-09-28

    The measurement of positron--nucleus collisions was used to estimate the possibility of suppressing background events that simulate $\\beta\\beta$ decay in the emulsion region adjacent to molybdenum conglomerates. The range of the escape of two relativistic particles from the interaction was found to be $ = (0.60\\pm 0.03) ~\\mu$m, which approximately corresponds to the grain size of developed nuclear emulsion. No correlation of the values of d with the angle between two relativistic particles was observed. It was shown that it was possible to exclude $\\beta\\beta$ decay background from electrons emerging in the decay of elements of naturally occurring radioactive chains. The background from $\\beta$ decays of $^{90}$Sr and $^{40}$K available in emulsion around Mo conglomerates was determined by the ratio of the volume $(\\sim d^3)$ to the total volume of emulsion and was found to be $1.5\\cdot 10^{-2}$. It was shown that the backgrounds from $^{40}$K, $^{90}$Sr and natural radioactivity could be significantly suppressed and would not limit the sensitivity of the experiment with 1 kg $^{100}$Mo.

  9. The Rheology of a Three Component System: COAL/WATER/#4 Oil Emulsions.

    NASA Astrophysics Data System (ADS)

    Gilmartin, Barbara Jean

    The purpose of this investigation was to study the rheology of a three component system, coal/water/#4 oil emulsions (COW), in which the third component, water, was present in a significant concentration, and to determine the applicability of existing theories from suspension rheology to the three component system studied. In a coal/water/oil emulsion, free coal particles adhere to the surface of the water droplets, preventing their coagulation, while the larger coal particles reside in the matrix of stabilized water droplets. The use of liquid fuels containing coal is a means of utilizing our nation's coal reserves while conserving oil. These fuels can be burned in conventional oil-fired furnaces. In this investigation, a high sulfur, high ash, bituminous coal was used, along with a heavy #4 oil to prepare the emulsions. The coal was ground to a log-normal distribution with an average particle size of 62 microns. A Haake RV3 concentric cylinder viscometer, with a ribbed measuring system, was used to determine the viscosity of the emulsions. A physical pendulum settling device measured the shift in center of mass of the COW as a function of time. The flow behavior of the fuel in pipes was also tested. In interpreting the data from the viscometer and the pipe flow experiments, a power law analysis was used in the region from 30 s('-1) to 200 s('-1). Extrapolation methods were used to obtain the low and high shear behavior of the emulsions. In the shear rate region found in boiler feed systems, COW are shear thinning with a flow behavior index of 0.7. The temperature dependent characteristic of the emulsions studied were similar and followed an Arrhenius type relationship. The viscosity of the COW decreases with increasing coal average particle size and is also a function of the width of the size distribution used. The type of coal used strongly influences the rheology of the fuel. The volatile content and the atomic oxygen to nitrogen ratio of the coal are the most predictive factors in terms of the variation in viscosity of the emulsion with coal type. The viscosity of the oil used is linearly related to the viscosity of the COW. The relative viscosity - concentration relationship for the emulsions was evaluated by an equation developed by Quemada for use in blood rheology: (eta)(,r) = (1 - (phi)/(phi)(,max))('-2). The best fit of the data to the equation was found when the coal plus water concentration was used for (phi). The maximum packing fraction increased with increasing shear rate, reflecting a breaking up of the agglomerates in the system. By using the relative packing fraction of the coal plus oil concentration, the relative viscosity of the emulsions tested at the three shear rates evaluted can be fit to the Quemada relative viscosity equation. In the pipe flow tests, the emulsions showed little time-dependent behavior, however they did exhibit a well effect. A fair correlation was obtained between pipe flow behavior and the results obtained in the viscometer. Coal/water/#4 oil emulsions behave as coal and water in oil systems and can be successfully modeled using theories from suspension rheology.

  10. A comparative study of the physicochemical properties of a virgin coconut oil emulsion and commercial food supplement emulsions.

    PubMed

    Khor, Yih Phing; Koh, Soo Peng; Long, Kamariah; Long, Shariah; Ahmad, Sharifah Zarah Syed; Tan, Chin Ping

    2014-01-01

    Food manufacturers are interested in developing emulsion-based products into nutritional foods by using beneficial oils, such as fish oil and virgin coconut oil (VCO). In this study, the physicochemical properties of a VCO oil-in-water emulsion was investigated and compared to other commercial oil-in-water emulsion products (C1, C2, C3, and C4). C3 exhibited the smallest droplet size of 3.25 µm. The pH for the emulsion samples ranged from 2.52 to 4.38 and thus were categorised as acidic. In a texture analysis, C2 was described as the most firm, very adhesive and cohesive, as well as having high compressibility properties. From a rheological viewpoint, all the emulsion samples exhibited non-Newtonian behaviour, which manifested as a shear-thinning property. The G'G'' crossover illustrated by the VCO emulsion in the amplitude sweep graph but not the other commercial samples illustrated that the VCO emulsion had a better mouthfeel. In this context, the VCO emulsion yielded the highest zeta potential (64.86 mV), which was attributed to its strong repulsive forces, leading to a good dispersion system. C2 comprised the highest percentage of fat among all emulsion samples, followed by the VCO emulsion, with 18.44% and 6.59%, respectively. PMID:24988188

  11. Ultrasonication-assisted preparation and characterization of emulsions and emulsion gels for topical drug delivery.

    PubMed

    Singh, Vinay K; Behera, Baikuntha; Pramanik, Krishna; Pal, Kunal

    2015-03-01

    The current study describes the use of ultrasonication for the preparation of biphasic emulsions and emulsion gels for topical drug delivery. Sorbitan monostearate (SMS) was used as the surfactant for stabilizing the interface of sesame oil (apolar phase) and water (polar phase). Emulsions were formed at lower concentrations of SMS, whereas emulsion gels were formed at higher concentrations of SMS. The formulations were characterized by fluorescent microscopy, X-ray diffraction, viscosity, stress relaxation, spreadability, and differential scanning calorimetry studies. Fluorescence microscopy suggested formation of oil-in-water type of formulations. There was an increase in the viscosity, bulk resistance, and firmness of the formulations as the proportions of SMS was increased. The emulsion gels were viscoelastic in nature. Thermal studies suggested higher thermodynamic stability at higher proportions of either SMS or water. Metronidazole, a model antimicrobial drug, was incorporated within the formulations. The release of the drug from the formulations was found to be diffusion mediated. The drug-loaded formulations showed sufficient antimicrobial efficiency to be used as carriers for topical antimicrobial drug delivery. PMID:25470664

  12. Automatic readout for nuclear emulsions in muon radiography of volcanoes

    NASA Astrophysics Data System (ADS)

    Aleksandrov, A.; Bozza, C.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Di Marco, N.; Kose, U.; Lauria, A.; Medinaceli, E.; Miyamoto, S.; Montesi, C.; Pupilli, F.; Rescigno, R.; Russo, A.; Sirignano, C.; Stellacci, S. M.; Strolin, P.; Tioukov, V.

    2012-04-01

    Nuclear emulsions are an effective choice in many scenarios of volcano radiography by cosmic-ray muons. They are cheap and emulsion-based detectors require no on-site power supply. Nuclear emulsion films provide sub-micrometric tracking precision and intrinsic angular accuracy better than 1 mrad. Imaging the inner structure of a volcano requires that the cosmic-ray absorption map be measured on wide angular range. High-absorption directions can be probed by allowing for large statistics, which implies a large overall flux, i.e. wide surface for the detector. A total area of the order of a few m2 is nowadays typical, thanks to the automatic readout tools originally developed for high-energy physics experiments such as CHORUS, PEANUT, OPERA. The European Scanning System is now being used to read out nuclear emulsion films exposed to cosmic rays on the side of volcanoes. The structure of the system is described in detail with respect to both hardware and software. Its present scanning speed of 20 cm2/h/side/microscope is suitable to fulfil the needs of the current exposures of nuclear emulsion films for muon radiograph, but it is worth to notice that applications in volcano imaging are among the driving forces pushing to increase the performances of the system. Preliminary results for the Unzen volcano of a joint effort by research groups in Italy and Japan show that the current system is already able to provide signal/background ratio in the range 100÷10000:1, depending on the quality cuts set in the off-line data analysis. The size of the smallest detectable structures in that experimental setup is constrained by the available statistics in the region of highest absorption to about 50 mrad, or 22 m under the top of the mountain. Another exposure is currently taking data at the Stromboli volcano. Readout of the exposed films is expected to begin in March 2012, and preliminary results will be available soon after. An effort by several universities and INFN has already started to increase the scanning speed, to exceed 100 cm2/h and approach the order of magnitude of 1000 cm2/h. Muon radiography also demands high signal/background ratio to probe high absorption regions in volcanoes. A new camera, a new image acquisition device, an improved motion control board and extensive use of GPU-based processing are the keys to make a new leap in speed while even improving data quality. With most of the new hardware already finalised, software development is quickly progressing, and a stable, user-friendly and cheap prototype is expected to be ready to take data already this summer. The amount of raw data collected is typically of the order of 10 TB/m2. The operation of automatic microscopes is thus complemented with an automatic data management and processing system based on a distributed computing model. The processing power can be scaled up linearly by just increasing the number of available computers. An evolution is underway on this side too, and algorithms designed for GPU-based processing will soon help increase the available power while decreasing the overall cost of typical installations.

  13. Anti-Inflammatory and Anti-Fibrotic Profile of Fish Oil Emulsions Used in Parenteral Nutrition-Associated Liver Disease

    PubMed Central

    Pastor-Clerigues, Alfonso; Marti-Bonmati, Ezequiel; Milara, Javier; Almudever, Patricia; Cortijo, Julio

    2014-01-01

    Home parenteral nutrition (PN) is associated with many complications including severe hepatobiliary dysfunction. Commercial ?-6 fatty acid-soybean based-lipid emulsions in PN may mediate long term PN associate liver disease (PNALD) whereas ?-3-fish oil parenteral emulsions have shown to reverse PNALD in children. However, its clinical effectiveness in adults has been scarcely reported. In this work, we study the role of soybean and fish oil lipid commercial emulsions on inflammatory and profibrotic liver markers in adults with long term PNALD and in in vitro cellular models. Inflammatory and profibrotic markers were measured in serum of ten adults with long term PNALD and in culture supernatants of monocytes. Liver epithelial to mesenchymal transition (EMT) was induced by transforming growth factor beta 1 (TGF?1) to evaluate in vitro liver fibrosis. Omegaven®, a 100% fish oil commercial emulsion, was infused during four months in two patients with severe long term PNALD reversing, at the first month, the inflammatory, profibrotic and clinical parameters of PNALD. The effect was maintained during the treatment course but impaired when conventional lipid emulsions were reintroduced. The other patients under chronic soybean oil-based PN showed elevated inflammatory and profibrotic parameters. In vitro human monocytes stimulated with lipopolysaccharide induced a strong inflammatory response that was suppressed by Omegaven®, but increased by soybean emulsions. In other experiments, TGF?1 induced EMT that was suppressed by Omegaven® and enhanced by soybean oil lipid emulsions. Omegaven® improves clinical, anti-inflammatory and anti-fibrotic parameters in adults with long-term home PNALD. PMID:25502575

  14. Heavy crude oils/particle stabilized emulsions.

    PubMed

    Kralova, Iva; Sjöblom, Johan; Øye, Gisle; Simon, Sébastien; Grimes, Brian A; Paso, Kristofer

    2011-12-12

    Fluid characterization is a key technology for success in process design for crude oil mixtures in the future offshore. In the present article modern methods have been developed and optimized for crude oil applications. The focus is on destabilization processes in w/o emulsions, such as creaming/sedimentation and flocculation/coalescence. In our work, the separation technology was based on improvement of current devices to promote coalescence of the emulsified systems. Stabilizing properties based on particles was given special attention. A variety of particles like silica nanoparticles (AEROSIL®), asphalthenes, wax (paraffin) were used. The behavior of these particles and corresponding emulsion systems was determined by use of modern analytical equipment, such as SARA fractionation, NIR, electro-coalescers (determine critical electric field), Langmuir technique, pedant drop technique, TG-QCM, AFM. PMID:22047991

  15. Pickering emulsions stabilized by nanoparticle surfactants.

    PubMed

    Larson-Smith, Kjersta; Pozzo, Danilo C

    2012-08-14

    Amphiphilic gold nanoparticles are demonstrated to effectively stabilize emulsions of hexadecane in water. Nanoparticle surfactants are synthesized using a simple and scalable one-pot method that involves the sequential functionalization of particle surfaces with thiol-terminated polyethylene glycol (PEG) chains and short alkane-thiol molecules. The resulting nanoparticles are shown to be highly effective emulsifying agents due to their strong adsorption at oil-water and air-water interfaces. The original nonfunctionalized gold nanoparticles are unable to effectively stabilize oil-water emulsions due to their small size and low adsorption energy. Small-angle X-ray scattering and electron microscopy are used to demonstrate the formation of nanoparticle-stabilized colloidosomes that are stable against coalescence and show significant shifts in plasmon resonance enhancing the near-infrared optical absorption. PMID:22823547

  16. Continuous phases in emulsions of three liquids

    SciTech Connect

    Smith, D.H. (Morgantown Energy Technology Center, WV (United States) Univ. of Oklahoma, Norman (United States)); Johnson, G.K. (Morgantown Energy Technology Center, WV (United States)); Dadyburjor, D.B. (West Virginia Univ., Morgantown (United States))

    1993-08-01

    For three-phase (macro)emulsions formed by the top (T), middle (M), and bottom (B) phases of amphiphile/oil/water systems, it has been variously stated in the literature either (1) that the continuous phase is always M or (2) that the continuous phase is B below the phase inversion temperature (PIT) and T above the PIT. We show by means of isothermal electrical conductivity measurements at various temperatures on emulsions of known phase volume fractions that neither hypothesis is generally correct. For our experimental conditions the [open quotes]choice[close quotes] of continuous phase depends on the phase volume fractions, and at all temperatures - by appropriate choice of phase volume fractions - any of T, M, or B may be made the continuous phase. 21 refs., 6 figs.

  17. Emulsions Containing Perfluorocarbon Support Cell Cultures

    NASA Technical Reports Server (NTRS)

    Ju, Lu-Kwang; Lee, Jaw Fang; Armiger, William B.

    1990-01-01

    Addition of emulsion containing perfluorocarbon liquid to aqueous cell-culture medium increases capacity of medium to support mammalian cells. FC-40 Fluorinert (or equivalent) - increases average density of medium so approximately equal to that of cells. Cells stay suspended in medium without mechanical stirring, which damages them. Increases density enough to prevent cells from setting, and increases viscosity of medium so oxygen bubbled through it and nutrients stirred in with less damage to delicate cells.

  18. VISCOSITY OF WATER IN OIL EMULSIONS

    Microsoft Academic Search

    M. Benayoune; L. Khezzar; M. Al-Rumhy

    1998-01-01

    Increase in water cut in oil fields generally calls for an increase in the capacity of transport pipelines. Proper design and operation of the latter requires good knowledge of the thermophysical properties of flow resistance of crude-oil water mixtures. An experimental program aimed at measurements of oil-water emulsion viscosity for water cuts prior to the inversion point was conducted.The present

  19. 40 CFR 467.20 - Applicability; description of the rolling with emulsions subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...description of the rolling with emulsions subcategory. 467.20 Section...POINT SOURCE CATEGORY Rolling With Emulsions Subcategory § 467.20 Applicability...description of the rolling with emulsions subcategory. This...

  20. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Applicability; description of the asphalt emulsion subcategory. 443.10 Section...POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions...

  1. Controllable microfluidic production of multicomponent multiple emulsions Xiao-Jie Ju,a

    E-print Network

    Controllable microfluidic production of multicomponent multiple emulsions Wei Wang,a Rui Xie multiple emulsions. The number, ratio and size of droplets, each with distinct contents being inde to create higher-order multicomponent multiple emulsions with exceptionally diverse structures

  2. 40 CFR 467.20 - Applicability; description of the rolling with emulsions subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...description of the rolling with emulsions subcategory. 467.20 Section...POINT SOURCE CATEGORY Rolling With Emulsions Subcategory § 467.20 Applicability...description of the rolling with emulsions subcategory. This...

  3. Monodisperse Emulsion Generation via Drop Break Off in a Coflowing Stream

    E-print Network

    Monodisperse Emulsion Generation via Drop Break Off in a Coflowing Stream P. B. Umbanhowar,*, V monodisperse emulsions (with minimum achievable polydispersities tension of the two phases. Emulsions composed of a variety of fluids and with drop sizes ranging from 2

  4. Emulsion-Based Synthesis of Reversibly Swellable, Magnetic Nanoparticle-Embedded Polymer Microcapsules

    E-print Network

    Velev, Orlin D.

    Emulsion-Based Synthesis of Reversibly Swellable, Magnetic Nanoparticle-Embedded Polymer mixture containing liquid prepolymer and MPs in chloroform solution, double emulsions comprising emulsions converted to microcapsules with a polymerized composite shell. The evolution from the double

  5. 40 CFR 467.20 - Applicability; description of the rolling with emulsions subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...description of the rolling with emulsions subcategory. 467.20 Section...POINT SOURCE CATEGORY Rolling With Emulsions Subcategory § 467.20 Applicability...description of the rolling with emulsions subcategory. This...

  6. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the asphalt emulsion subcategory. 443.10 Section...POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions...

  7. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the asphalt emulsion subcategory. 443.10 Section...POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions...

  8. 40 CFR 467.20 - Applicability; description of the rolling with emulsions subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...description of the rolling with emulsions subcategory. 467.20 Section...POINT SOURCE CATEGORY Rolling With Emulsions Subcategory § 467.20 Applicability...description of the rolling with emulsions subcategory. This...

  9. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the asphalt emulsion subcategory. 443.10 Section...POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions...

  10. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability; description of the drawing with emulsions or soaps subcategory. 467.60 Section...POINT SOURCE CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 ...Applicability; description of the drawing with emulsions or soaps subcategory. This...

  11. 40 CFR 443.10 - Applicability; description of the asphalt emulsion subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability; description of the asphalt emulsion subcategory. 443.10 Section...POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10 Applicability; description of the asphalt emulsion subcategory. The provisions...

  12. 78 FR 58318 - Clinical Trial Design for Intravenous Fat Emulsion Products; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-23

    ...Clinical Trial Design for Intravenous Fat Emulsion Products; Public Workshop AGENCY: Food...Clinical Trial Design for Intravenous Fat Emulsion Products.'' This workshop will provide...support registration of intravenous fat emulsion products. Date and Time: The...

  13. 40 CFR 467.20 - Applicability; description of the rolling with emulsions subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...description of the rolling with emulsions subcategory. 467.20 Section...POINT SOURCE CATEGORY Rolling With Emulsions Subcategory § 467.20 Applicability...description of the rolling with emulsions subcategory. This...

  14. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...description of the drawing with emulsions or soaps subcategory. 467.60 Section 467...SOURCE CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability...description of the drawing with emulsions or soaps subcategory. This subpart...

  15. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...description of the drawing with emulsions or soaps subcategory. 467.60 Section 467...SOURCE CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability...description of the drawing with emulsions or soaps subcategory. This subpart...

  16. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...description of the drawing with emulsions or soaps subcategory. 467.60 Section 467...SOURCE CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability...description of the drawing with emulsions or soaps subcategory. This subpart...

  17. 40 CFR 467.60 - Applicability; description of the drawing with emulsions or soaps subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...description of the drawing with emulsions or soaps subcategory. 467.60 Section 467...SOURCE CATEGORY Drawing With Emulsions or Soaps Subcategory § 467.60 Applicability...description of the drawing with emulsions or soaps subcategory. This subpart...

  18. Crosslinkable poly(vinyl acetate) emulsions for wood adhesive

    Microsoft Academic Search

    Jia Lu; Allan J. Easteal; Neil R. Edmonds

    2011-01-01

    Purpose – The purpose of this paper is to enhance the water resistance and the heat resistance of poly(vinyl acetate) (PVAc) emulsion adhesive, by providing the emulsion with controllable thermosetting capability. Design\\/methodology\\/approach – Emulsion polymerisation was used to synthesise PVAc\\/VeoVa 10 copolymers with varying proportions of acetoacetoxyethyl methacrylate (AAEM) incorporated in the copolymer chains. The AAEM component provided sites for

  19. Pipeline flow of unstable and surfactant-stabilized emulsions

    Microsoft Academic Search

    Rajinder Pal

    1993-01-01

    The literature available on pipeline flow behavior of emulsions is reviewed critically. New results concerning the laminar and turbulent flow behaviors of unstable (without any added surfactant) and surfactant-stabilized water-in-oil emulsions are presented. The unstable emulsions exhibit drag reduction behavior in turbulent flow; the measured friction factors fall well below the values expected on the basis of the laminar flow

  20. Electrocoalescence of drops in a water-in-oil emulsion

    Microsoft Academic Search

    Jorunn Holto; Gunnar Berg; Lars E. Lundgaard

    2009-01-01

    Electrocoalescence of water drops in a stagnant water-in-oil emulsion has been studied in a newly developed test cell. An homogeneous electric field was applied across the emulsion volume. It was used to observe drop behaviour in a multi-drop system. The emulsion was made of napthenic oil containing chemically stabilized water drops with size in the range of 5-100 ¿m. Insulated

  1. Chemical Demulsification of Water-in-Crude Oil Emulsions

    Microsoft Academic Search

    Abdurahman; H. Nour; Rosli Mohd Yunus; Zulkifly Jemaat

    2007-01-01

    Demulsification (emulsion breaking) is necessary in many practical applications such as the petroleum industry, painting and waste-water treatment in environmental technology. Chemical demulsification is the most widely applied method of treating water-in-crude oil emulsions and involves the use of chemical additives to accelerate the emulsion breaking process. The effect of chemical demulsification operations on the stability and properties of water-in-crude

  2. Stability Investigation of Water-in-Crude Oil Emulsion

    Microsoft Academic Search

    Abdurahman H. Nour; Rosli Mohd. Yunus

    2006-01-01

    The water in-crude oil emulsion has great importance in the oil industry. Experimental data are presented to investigate the stability of water-in-crude oil emulsions in both creaming and coalescence states were measured as a function of sodium chloride concentration. Also the stability of w\\/o emulsion is investigated over a wide range of parameters. These parameters are salt concentration (0-5.5%), mixing

  3. THE INFLUENCE OF HELICAL FLOW ON WATER FUEL EMULSION PREPARATION

    Microsoft Academic Search

    E. D?uska; R. Hubacz; S. Wro?ski; J. Kamie?ski; M. Dyl?g; R. Wójtowicz

    2007-01-01

    This study presents a method of preparing simple and multiple emulsions formed in a liquid-liquid contactor with Couette-Taylor flow (CTF). A Couette-Taylor flow contactor represents a mini-channel device, and due to its small dimension can be connected to a diesel engine for just-prepared emulsion injection. Stable simple W\\/O and multiple O\\/W\\/O emulsions have been prepared, both with quite narrow drop

  4. Simple and Multiple Water Fuel Emulsions Preparation in Helical Flow

    Microsoft Academic Search

    Ewa DLUSKA; Robert HUBACZ; Stanislaw WRONSKI

    This paper presents a method of simple and multiple water fuel emulsions preparation in a liquid-liquid contactor with Couette-Taylor flow (CTF contactor). This method concerns the integration of the CTF contactor with diesel engines for the injection of just-prepared emulsions. Stable simple O\\/W and multiple O\\/W\\/O emulsions, both with quite narrow drop size distribution, have been prepared. The strong influence

  5. Application of petroleum demulsification technology to shale oil emulsions

    SciTech Connect

    Robertson, R.E.

    1983-01-01

    Demulsification, the process of emulsion separation, of water-in-oil shale oil emulsions produced by several methods was accomplished using commercial chemical demulsifiers which are used typically for petroleum demulsification. The shale oil emulsions were produced from Green River shale by one in situ and three different above-ground retorts, an in situ high pressure/high temperature steam process, and by washing both retort-produced and hydrotreated shale oils.

  6. Simple and double emulsions via electrospray

    NASA Astrophysics Data System (ADS)

    Barrero, Antonio; Loscertales, Ignacio G.

    2005-11-01

    Generation of nanoemulsions is of great interest in medical and pharmaceutical applications; drug delivery or antiviral emulsions are typical examples. The use of electrosprays for dispersing liquids inside liquid insulator baths have been recently reported, (Barrero et al. J. Colloid Interf. Sci. 272, 104, 2004). Capsules, nanotubes and coaxial nanofibers have been obtained from electrified coaxial jets (Loscertales et al. Science 295, n. 5560, 1695, 2002; J. American Chem. Soc. 126, 5376, 2004). Here we present a method for making double emulsions (both water-oil-water and o/w/o) based on the generation of compound electrosprays inside insulator liquid baths. Basically, a conducting liquid injected throughout a capillary needle is electroatomized in cone-jet mode inside a dielectric liquid bath. A third insulating liquid is injected inside the Taylor cone to form a second meniscus. Then, a steady coaxial jet, in which the insulating liquid is coated by the conducting one, develops. A double emulsion forms as a result of the jet breaking up into compound droplets electrically charged. Experimental results carried out with glycerine and different oils in a bath of heptane are reported.

  7. Laboratory effectiveness testing of water-in-oil emulsion breakers

    SciTech Connect

    Fingas, M.F.; Fieldhouse, B.; Bier, I.; Conrod, D. [Environment Canada, Ottawa, Ontario (Canada); Tennyson, E. [Minerals Management Service, Herndon, VA (United States)

    1995-06-01

    The physics and chemistry of water-in-oil emulsions dominate the development of effectiveness tests. Emulsions are variable in stability--this variability is largely dependent on oil type and degree of weathering. These factors complicate the development of a test. Emulsions which have low stability will apparently break easily with chemical emulsion breakers. Broken emulsions will form a foam-like material, called rag, which retains water which is not part of the stable emulsions. Analytical methods used to determine the final stability of the broken or unbroken emulsion were evaluated. Measurements of water content and viscosity measurements show correlation to emulsion stability. Viscosity provides a more reliable measure of emulsion stability but water content measurements are more convenient and are largely used in this study. Twelve tests were developed in the past. Two testing methods have been developed to a usable stage. These tests are described and data using them provided. The effects of mixing time, agent amount, settling time and mixing energy on effectiveness results are presented.

  8. Fat emulsion composition alters intake and the effects of baclofen.

    PubMed

    Wang, Y; Wilt, D C; Wojnicki, F H E; Babbs, R K; Coupland, J N; Corwin, R L C

    2011-12-01

    Thickened oil-in-water emulsions are useful model foods in rat studies due to their high acceptance and similarity to foods consumed by humans. Previous work from this laboratory used oil-in-water emulsions thickened with a biopolymer blend containing starch. Intake and effects of baclofen, a GABA-B agonist that decreases fat intake and drug self-administration, were reported, but the contribution of starch was not assessed. In the present study, intake and effects of baclofen were assessed in rats using emulsions prepared with two fat types (32% vegetable shortening, 32% corn oil) and thickened with three biopolymer blends. One biopolymer blend contained starch and the other two did not. Daily 1-h intake of the vegetable shortening emulsion containing starch was significantly greater than the other emulsions. When starch was added to the emulsions originally containing no starch, intake significantly increased. Baclofen generally reduced intake of all emulsions regardless of starch content and stimulated intake of chow. However, effects were more often significant for vegetable shortening emulsions. This report: (1) demonstrates that products used to prepare thickened oil-in-water emulsions have significant effects on rat ingestive behavior, and (2) confirms the ability of baclofen to reduce consumption of fatty foods, while simultaneously stimulating intake of chow. PMID:21855586

  9. A multivariate screening analysis of W/O emulsions in high external electric fields as studied by means of dielectric time domain spectroscopy. 2: Model emulsions stabilized by interfacially active fractions from crude oils

    SciTech Connect

    Foerdedal, H.; Midttun, O.; Sjoeblom, J.; Kvalheim, O.M. [Univ. of Bergen (Norway). Dept. of Chemistry] [Univ. of Bergen (Norway). Dept. of Chemistry; Schildberg, Y.; Volle, J.L. [Elf Aquitaine Production, Pau (France)] [Elf Aquitaine Production, Pau (France)

    1996-09-01

    The electrically induced coalescence of water-in-oil emulsions stabilized by interfacially active fractions from crude oils has been studied by means of time domain dielectric spectroscopy at high electric fields. The experiments were designed with a 2{sup 7-3} reduced factorial design. Regression analysis clearly shows that the choice of organic solvent and the amount of asphaltenes, as well as the interplay between these variables, are the most significant parameters for determining the stability of these emulsions. It should be pointed out that the asphaltenes were the only surface active fraction tested. No interplay between, for instance, asphaltenes and resins was investigated. The nonlinearity found in the regression analysis is explained by different aggregation states of asphaltenes in aliphatic and aromatic solvents. The influence of the variables upon the emulsion stability is discussed.

  10. An electro-coalescence chip for effective emulsion breaking in droplet microfluidics.

    PubMed

    Chokkalingam, Venkatachalam; Ma, Yujie; Thiele, Julian; Schalk, Werner; Tel, Jurjen; Huck, Wilhelm T S

    2014-07-21

    Droplet-based microfluidics is increasingly used for biological applications, where the recovery of cells or particles after an experiment or assay is desirable. Here, we present an electro-demulsification chip which circumvents the use of harsh chemicals and multiple washing/centrifugation steps and offers a mild way for extracting cells and polymer particles into an aqueous phase from microfluidic water-in-oil emulsions. PMID:24889537

  11. Use of oil-emulsion mud in the Sivells Bend Field: Gas and gas condensate operations for the independent producer.

    E-print Network

    Echols, Walter Harlan

    1954-01-01

    obtained between oil-emulsion mud and water-base mud as used in the develop- ment of Strawn sand wells iu a North Texas field. (Presented at the New York Meeting of the A. I. PL E. , March 1947; ublished in Petroleum Technolo@r, tuIF 1947~ end..., consisting of a mixture of oil-base mud and bentonitic water-base mud, has been used experimentally in drilling 8 of the 35 wells in the Sivells Bend field, Cooke County, Texas. Experience indicates the oil-emulsion mud can be controlled in much...

  12. Induction of Infection in Sesbania exaltata by Colletotrichum gloeosporioides f. sp. aeschynomene Formulated in an Invert Emulsion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In greenhouse experiments, an experimental invert emulsion (MSG 8.25) was tested as an adjuvant with spores of the mycoherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene, a highly virulent pathogen of the leguminous weed Aeschynomene virginica (northern jointvetch), but non-pathoge...

  13. Linear viscoelasticity of emulsions. Part 2. Measurements of the linear viscoelastic behavior of emulsions in the kilohertz range

    SciTech Connect

    Oosterbroek, M.; Mellema, J.; Lopulissa, J.S.

    1981-11-01

    Linear viscoelasticity of emulsions in shear deformation in the kilohertz range is demonstrated experimentally. In order to avoid complications due to inertia effects, emulsions with small droplet sizes are studied. The preliminary measurements are interpreted as being the result of droplet deformations. If this interpretation is correct, measurements of the dynamic viscosity of emulsions may be used to obtain information about the mechanical properties of the interfacial layer between droplets and the continuous phase. In particular, the evaluation of the interfacial tension of emulsion droplets from bulk properties might be possible using this technique. 21 references.

  14. A novel approach to dark matter search based on nanometric emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Asada, T.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Di Marco, N.; Furuya, S.; Gentile, V.; Hakamata, K.; Ishikawa, M.; Katsuragawa, T.; Kuwabara, K.; Machii, S.; Naka, T.; Pupilli, F.; Sirignano, C.; Tawara, Y.; Tioukov, V.; Umemoto, A.; Yoshimoto, M.

    2014-12-01

    The most convincing candidate as main constituent of the dark matter in the Universe consists of weakly interacting massive particles (WIMP). WIMPs must be electrically neutral and interact with a very low cross-section (? < 10?40 cm2) which makes them detectable in direct searches only through the observation of nuclear recoils induced by the WIMP rare scatterings. In the experiments carried out so far, recoiled nuclei are searched for as a signal over a background produced by Compton electrons and neutron scatterings. Signal found by some experiments have not been confirmed by other techniques. None of these experiments is able to detect the track, typically less than one micron long, of the recoiled nucleus and therefore none is able to directly detect the incoming direction of WIMPs. We propose an R&D program for a new experimental method able to observe the track of the scattered nucleus based on new developments in the nuclear emulsion technique: films with nanometric silver grains, expansion of emulsions and very fast completely automated scanning systems. Nuclear emulsions would act both as the WIMP target and as the tracking detector able to reconstruct the direction of the recoiled nucleus. This unique characteristic would provide a new and unambiguous signature of the presence of the dark matter in our galaxy.

  15. Crude oil emulsions containing a compatible fluorochemical surfactant

    SciTech Connect

    Karydas, A.; Rodgers, J.

    1991-02-19

    This patent describes a crude oil in water emulsion, which is stable to both breakdown and phase inversion up to at least about 50{degrees} C., the emulsion containing an effective, compatible, emulsion stabilizing amount of a fluorochemical surfactant of the formula (R{sub {ital f}}){sub {ital n}}A{sub {ital m}}Q wherein R{sub {ital f}} is an inert, stable, oleophobic and hydrophobic fluoroaliphatic group having up to about 20 carbon atoms; n is an integer from 1 to 3; A is a direct bond or an organic linking group and is covalently bonded to both R{sub {ital f}} and Q; Q is an anionic, nonionic or amphoteric group; and m is an integer from 1 to 3; wherein the amount of weight of the fluorochemical surfactant present in the emulsion being between about 0.001 and 1% by weight of the emulsion, in the presence of absence of up to about 2% by weight of a crude oil emulsion promoting hydrocarbon surfactant, with the proviso that at least about 0.005% by weight total fluorochemical and hydrocarbon surfactant is present, based upon the weight of emulsion, and wherein the emulsion contains bout 15 to about 90 percent by weight water, based upon the weight of emulsion, such that the viscosity of the emulsion is less than about 50% of the viscosity of the crude oil, and wherein the emulsion spontaneously breaks down into an aqueous and crude oil phase at a temperature between about 55{degrees} and 75{degrees} C.

  16. Tocopherol and tocotrienol homologs in parenteral lipid emulsions

    PubMed Central

    Xu, Zhidong; Harvey, Kevin A; Pavlina, Thomas M; Zaloga, Gary P; Siddiqui, Rafat A

    2015-01-01

    Parenteral lipid emulsions, which are made of oils from plant and fish sources, contain different types of tocopherols and tocotrienols (vitamin E homologs). The amount and types of vitamin E homologs in various lipid emulsions vary considerably and are not completely known. The objective of this analysis was to develop a quantitative method to determine levels of all vitamin E homologs in various lipid emulsions. An HPLC system was used to measure vitamin E homologs using a Pinnacle DB Silica normal phase column and an isocratic, n-hexane:1,4 dioxane (98:2) mobile phase. An optimized protocol was used to report vitamin E homolog concentrations in soybean oil-based (Intralipid®, Ivelip®, Lipofundin® N, Liposyn® III, and Liposyn® II), medium- and long-chain fatty acid-based (Lipofundin®, MCT and Structolipid®), olive oil-based (ClinOleic®), and fish oil-based (Omegaven®) and mixture of these oils-based (SMOFlipid®, Lipidem®) commercial parenteral lipid emulsions. Total content of all vitamin E homologs varied greatly between different emulsions, ranging from 57.9 to 383.9 µg/mL. Tocopherols (?, ?, ?, ?) were the predominant vitamin E homologs for all emulsions, with tocotrienol content < 0.3%. In all of the soybean emulsions, except for Lipofundin® N, the predominant vitamin E homolog was ?-tocopherol, which ranged from 57–156 µg/mL. ClinOleic® predominantly contained ?-tocopherol (32 µg/mL), whereas ?-tocopherol content in Omegaven® was higher than most of the other lipid emulsions (230 µg/mL). Practical applications The information on the types and quantity of vitamin E homologs in various lipid emulsions will be extremely useful to physicians and healthcare personnel in selecting appropriate lipid emulsions that are exclusively used in patients with inadequate gastrointestinal function, including hospitalized and critically ill patients. Some emulsions may require vitamin E supplementation in order to meet minimal human requirements. PMID:25685054

  17. Process for the use of emulsions in petroleum recovery

    Microsoft Academic Search

    Coppel

    1968-01-01

    An oil-external emulsion composed of water, aliphatic or aromatic hydrocarbons, and a surfactant can be used for oil recovery. The viscosity of the emulsion can be varied for mobility control by varying the quantity of water present. Soft water is preferred for this composition. However, the choice of surfactant can be varied to accommodate water containing some calcium and magnesium

  18. Preparation of food emulsions using a membrane emulsification system

    Microsoft Academic Search

    Ryoh Katoh; Yuzoh Asano; Atusi Furuya; Kazuyoshi Sotoyama; Mamoru Tomita

    1996-01-01

    In emulsions prepared using a membrane emulsification system, dispersion droplet diameter depends basically upon membrane pore diameter. For practical applications, it is necessary to select the appropriate type and concentration of emulsifiers, U and Je.For practical applications in the food industry, where large volume production is conducted, it is especially important to increase Je. When preparing an O\\/W emulsion, this

  19. Emulsion design to improve the delivery of functional lipophilic components.

    PubMed

    McClements, David Julian

    2010-01-01

    The food industry has used emulsion science and technology for many years to create a diverse range of food products, such as milk, cream, soft drinks, nutritional beverages, dressings, mayonnaise, sauces, dips, deserts, ice cream, margarine, and butter. The majority of these food products are conventional oil-in-water (O/W) or water-in-oil (W/O) type emulsions. Recently, there has been increasing interest within the food industry in either improving or extending the functional performance of foods using novel structured emulsions. This article reviews recent developments in the creation of structured emulsions that could be used by the food and other industries, including nanoemulsions, multiple emulsions, multilayer emulsions, solid lipid particles, and filled hydrogel particles. These structured emulsions can be produced from food-grade [generally recognized as safe (GRAS)] ingredients (e.g., lipids, proteins, polysaccharides, surfactants, and minerals), using simple processing operations (e.g., mixing, homogenizing, and thermal processing). The structure, production, performance, and potential applications of each type of structured emulsion system are discussed. PMID:22129337

  20. Emulsion separation rate enhancement with high frequency energy

    SciTech Connect

    Peterson, E.R. [Phonon Technologies, Inc., Houston, TX (United States)

    1997-06-01

    The preponderance of stable oil/water emulsions, commonly encountered as pit oils or tank bottoms and known as sludges, presents an ever worsening remediation problem to oil producers and refiners. As the world`s crudes become heavier, the problem of emulsion generation becomes larger. Increasing regulatory and worldwide environmental controls also drive the need for cost effective reclamation of emulsions and sludges. Traditional methods of heating emulsions to force them to separate are difficult to practice. Emulsions can be hard to pump or may leave residue on heat transfer surfaces. High temperature processing can lead to loss of valuable volatiles. Revolutionary, cost effect technology for high frequency (RFM) energy separation of oil emulsions has been developed by Imperial Petroleum Recovery Corporation. RFM energy energizes the aqueous, surfactant and solid particulate components selectively, providing differential energy input. Proper choice of frequency provides dynamic coupling of the energy field to the natural frequency of the water component of the emulsion, accelerating coalescence of the water droplets into a separated phase. Field results have demonstrated the unique capabilities of RFM energy to accelerate separation of oil/water emulsions.

  1. Demulsification of Emulsions Exploited by Enhanced Oil Recovery System

    Microsoft Academic Search

    Lixin Xia; Shiwei Lu; Guoying Cao

    2003-01-01

    Experimental data are presented to show the influence of the enhanced oil recovery system's components, alkali, surfactant, and polymer, on the demulsification and light transmittance of the water separated from the emulsions. Among which, the effects of surfactants, polyoxyethylene (10) alkylphenol ether (OP?10) and sodium petroleum sulfonate (CY?1) on emulsion stability, are the strongest of any component, the effects of

  2. Notes & Tips A streamlined protocol for emulsion polymerase chain reaction

    E-print Network

    Konthur, Zoltán

    Notes & Tips A streamlined protocol for emulsion polymerase chain reaction and subsequent online 25 November 2010 a b s t r a c t Compartmentalization of polymerase chain reaction (PCR) reduces denaturation steps in PCR [3]. A water-in-oil emulsion allows many reactions to occur inde- pendently

  3. Modeling of a Foamed Emulsion Bioreactor: II. Model Parametric Sensitivity

    E-print Network

    ARTICLE Modeling of a Foamed Emulsion Bioreactor: II. Model Parametric Sensitivity Eunsung Kan: The sensitivity of a conceptual model of a foam emulsion bioreactor (FEBR) used for the control of toluene vapors in air was examined. Model parametric sensitivity studies showed which parameters affect the removal

  4. Zero-Valent Metal Emulsion for Reductive Dehalogenation of DNAPLs

    NASA Technical Reports Server (NTRS)

    Reinhart, Debra R. (Inventor); Clausen, Christian (Inventor); Gelger, Cherie L. (Inventor); Quinn, Jacqueline (Inventor); Brooks, Kathleen (Inventor)

    2006-01-01

    A zero-valent metal emulsion is used to dehalogenate solvents, such as pooled dense non-aqueous phase liquids (DNAPLs), including trichloroethylene (TCE). The zero-valent metal emulsion contains zero-valent metal particles, a surfactant, oil and water, The preferred zero-valent metal particles are nanoscale and microscale zero-valent iron particles.

  5. Nanoscale and Microscale Iron Emulsions for Treating DNAPL

    NASA Technical Reports Server (NTRS)

    Geiger, Cherie L.

    2002-01-01

    This study demonstrated the feasibility of using emulsified nanoscale and microscale iron particles to enhance dehalogenation of (Dense Non-Aqueous Phase Liquid) DNAPL free-phase. The emulsified system consisted of a surfactant-stabilized, biodegradable oil-in-water emulsion with nanoscale or microscale iron particles contained within the emulsion droplets. It was demonstrated that DNAPLs, such as trichloroethene (TCE), diffuse through the oil membrane of the emulsion particle whereupon they reach an aqueous interior and the surface of an iron particle where dehalogenation takes place. The hydrocarbon reaction by-products of the dehalogenation reaction, primarily ethene (no chlorinated products detected), diffuse out of the emulsion droplet. This study also demonstrated that an iron-emulsion system could be delivered in-situ to the DNAPL pool in a soil matrix by using a simulated push well technique. Iron emulsions degraded pure TCE at a rate comparable to the degradation of dissolved phase TCE by iron particles, while pure iron had a very low degradation rate for free-phase TCE. The iron-emulsion systems can be injected into a sand matrix where they become immobilized and are not moved by flowing water. It has been documented that surfactant micelles possess the ability to pull pooled TCE into emulsion droplets where degradation of TCE takes place.

  6. Synthesis of metallic nanoshells on porphyrin-stabilized emulsions

    DOEpatents

    Wang, Haorong (Albuquerque, NM); Song, Yujiang (Albuquerque, NM); Shelnutt, John A. (Tijeras, NM); Medforth, Craig J. (Winters, CA)

    2011-12-13

    Metal nanostructures formed by photocatalytic interfacial synthesis using a porphyrin-stabilized emulsion template and the method for making the nanostructures. Catalyst-seeded emulsion droplets are employed as templates for hollow-nanoshell growth. The hollow metal nanospheres may be formed with or without inclusions of other materials.

  7. Zero-Valent Metal Emulsion for Reductive Dehalogenation of DNAPLS

    NASA Technical Reports Server (NTRS)

    Reinhart, Debra R. (Inventor); Clausen, Christian (Inventor); Geiger, Cherie L. (Inventor); Quinn, Jacqueline (Inventor); Brooks, Kathleen (Inventor)

    2003-01-01

    A zero-valent metal emulsion is used to dehalogenate solvents, such as pooled dense non-aqueous phase liquids (DNAPLs), including trichloroethylene (TCE). The zero-valent metal emulsion contains zero-valent metal particles, a surfactant, oil and water. The preferred zero-valent metal particles are nanoscale and microscale zero-valent iron particles

  8. Studies on the temperature performance of SBR modified asphalt emulsion

    Microsoft Academic Search

    Qinqin Zhang; Weiyu Fan; Tiezhu Wang; Guozhi Nan

    2011-01-01

    Styrene butadiene rubber (SBR) modified asphalt emulsions were prepared by means of SBR latex adding to aqueous solution, and it is an energy-saving, ecologically safe material because it does not need any heating processes creating gas emission and fire hazard during its use. The objective of this work was to analyze the temperature performance of SBR modified asphalt emulsions for

  9. Maximizing the stability of pyrolysis oil/diesel fuel emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several emulsions consisting of biomass pyrolysis oil (bio-oil) in diesel fuel were produced and analyzed for stability over time. An ultrasonic probe was used to generate microscopic droplets of bio-oil suspended in diesel fuel, and this emulsion was stabilized using surfactant chemicals. The most...

  10. Perfluorochemical emulsions decrease Kupffer cell phagocytosis.

    PubMed

    Bottalico, L A; Betensky, H T; Min, Y B; Weinstock, S B

    1991-07-01

    One drawback to using perfluorochemical emulsions as blood substitutes is that perfluorochemical particles are cleared from the blood by the reticuloendothelial system, primarily liver and spleen. We measured the impact of two perfluorochemical emulsions on clearance of colloidal carbon (less than 1 microns) and 51Cr-sheep red blood cells (about 8 microns) by the reticuloendothelial system in vivo and in the isolated perfused liver. Male rats were injected with 2 ml/100 gm body wt of Fluosol-DA or Oxypherol-ET for 4 consecutive days. Carbon (1 ml/100 gm body wt) or sheep red blood cells (0.05 ml of 5% vol/vol/100 gm body wt) were then injected intravenously (in vivo) or added to perfusate. Samples were taken at several time points for 1 hr. In the isolated perfused liver, carbon clearance was depressed by 25% 1 day after treatment. Rates returned to control levels by 12 days in Fluosol-DA-treated rats but remained depressed by 67% in Oxypherol-ET-treated rats. Sheep red blood cell (8 microns) clearance was two to five times slower than carbon clearance and depressed by 40% in livers from Fluosol-DA rats 1 day and 12 days after treatment. Added serum did not improve phagocytosis. In vivo carbon clearance remained normal in Fluosol-DA-treated rats but decreased by 74% in Oxypherol-ET-treated rats 1 day after treatment, returning to normal by 12 days. Clearance rates were similar in control rats in vivo and in the perfused liver. We conclude that the isolated perfused liver is a good model to measure liver clearance function. Although low doses of perfluorochemical emulsions may depress Kupffer cell phagocytosis, general reticuloendothelial system function is not significantly compromised. PMID:2066065

  11. Domain and droplet sizes in emulsions stabilized by colloidal particles

    E-print Network

    Frijters, Stefan; Harting, Jens

    2014-01-01

    Particle-stabilized emulsions are commonly used in various industrial applications. These emulsions can present in different forms, such as Pickering emulsions or bijels, which can be distinguished by their different topologies and rheology. We numerically investigate the effect of the volume fraction and the wettability of the stabilizing particles in mixtures of two fluids. For this, we use the well-established three-dimensional lattice Boltzmann method, extended to allow for the added colloidal particles with non-neutral wetting properties. We obtain data on the domain sizes in the emulsions by using both structure functions and the Hoshen-Kopelman (HK) algorithm, and demonstrate that both methods have their own (dis-)advantages. We confirm an inverse dependence between the concentration of particles and the average radius of the stabilized droplets. Furthermore, we demonstrate the effect of particles detaching from interfaces on the emulsion properties and domain size measurements.

  12. Development of an Acoustic Droplet Vaporization, Ultrasound Drug Delivery Emulsion

    NASA Astrophysics Data System (ADS)

    Fabiilli, Mario L.; Sebastian, Ian E.; Fowlkes, J. Brian

    2010-03-01

    Many therapeutic applications of ultrasound (US) include the use of pefluorocarbon (PFC) microbubbles or emulsions. These colloidal systems can be activated in the presence of US, which in the case of emulsions, results in the production of bubbles—a process known as acoustic droplet vaporization (ADV). ADV can be used as a drug delivery mechanism, thereby yielding the localized release of toxic agents such a chemotherapeutics. In this work, emulsions that contain PFC and chlorambucil, a chemotherapy drug, are formulated using albumin or lipid shells. For albumin droplets, the oil phase—which contained CHL—clearly enveloped the PFC phase. The albumin emulsion also displayed better retention of CHL in the absence of US, which was evaluated by incubating Chinese hamster ovary cells with the various formulations. Thus, the developed emulsions are suitable for further testing in ADV-induced release of CHL.

  13. Pickering emulsions for food applications: background, trends, and challenges.

    PubMed

    Berton-Carabin, Claire C; Schroën, Karin

    2015-01-01

    Particle-stabilized emulsions, also referred to as Pickering emulsions, have garnered exponentially increasing interest in recent years. This has also led to the first food applications, although the number of related publications is still rather low. The involved stabilization mechanisms are fundamentally different as compared to conventional emulsifiers, which can be an asset in terms of emulsion stability. Even though most of the research on Pickering emulsions has been conducted on model systems, with inorganic solid particles, recent progress has been made on the utilization of food-grade or food-compatible organic particles for this purpose. This review reports the latest advances in that respect, including technical challenges, and discusses the potential benefits and drawbacks of using Pickering emulsions for food applications, as an alternative to conventional emulsifier-based systems. PMID:25705932

  14. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project was to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, was used to remove inhibitory byproducts during fermentation; thus, improve the yield while reducing the need for fresh water. The key objectives of this study were: (1) Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems. (2) Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system. (3) Investigate the effect of gravity on emulsion coalescence within the membrane unit. (4) Access the effect of water re-use on fermentation yields in a model microbial system. and (5) Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts (not completed due to lack of funds)

  15. Domain and droplet sizes in emulsions stabilized by colloidal particles

    NASA Astrophysics Data System (ADS)

    Frijters, Stefan; Günther, Florian; Harting, Jens

    2014-10-01

    Particle-stabilized emulsions are commonly used in various industrial applications. These emulsions can present in different forms, such as Pickering emulsions or bijels, which can be distinguished by their different topologies and rheology. We numerically investigate the effect of the volume fraction and the uniform wettability of the stabilizing spherical particles in mixtures of two fluids. For this, we use the well-established three-dimensional lattice Boltzmann method, extended to allow for the added colloidal particles with non-neutral wetting properties. We obtain data on the domain sizes in the emulsions by using both structure functions and the Hoshen-Kopelman (HK) algorithm, and we demonstrate that both methods have their own (dis)advantages. We confirm an inverse dependence between the concentration of particles and the average radius of the stabilized droplets. Furthermore, we demonstrate the effect of particles detaching from interfaces on the emulsion properties and domain-size measurements.

  16. Temperature dependence of emulsion morphologies and the dispersion morphology diagram

    SciTech Connect

    Smith, D.H. (Univ. of Oklahoma, Norman (USA)); Covatch, G.C.; Lim, Kyunghee (Dept. of Energy, Morgantown, WV (USA))

    1991-02-07

    The recently constructed dispersion morphology diagram predicts that for amphiphile/oil/water systems there exists a range of concentrations within which only OL/AQ (oil-in-water) emulsions form and another range of concentrations for which the emulsion morphology is always AQ/OL (water-in-soil), regardless of whether the temperature is below the lower critical end-point temperature, above the upper critical end point, or between these two temperatures. These predictions contradict the PIT (phase inversion temperature) idea, that below the PIT amphiphile/oil/water systems for only oil-in-water emulsions and above the PIT they form only water-in-oil emulsions. By using electrical conductivity measurements to determine the emulsion morphologies at different temperatures for systems of constant composition, the authors show for the system studied that the previous predictions of the dispersion morphology diagram are correct.

  17. Electron/pion separation with an Emulsion Cloud Chamber by using a Neural Network

    E-print Network

    Arrabito, L; Bozza, C; Buontempo, S; Caffari, Y; Consiglio, L; Cozzi, M; D'Ambrosio, N; De Lellis, G; De Serio, M; Capua, F D; Ferdinando, D D; Marco, N D; Ereditato, A; Esposito, L S; Gagnebin, S; Giacomelli, G; Giorgini, M; Grella, G; Hauger, M; Ieva, M; Csathy, J J; Juget, F; Kreslo, I; Laktineh, I; Longhin, A; Mandrioli, G; Marotta, A; Marteau, J; Migliozzi, P; Monacelli, P; Moser, U; Muciaccia, M T; Pastore, A; Patrizii, L; Pistillo, C; Pozzato, M; Romano, G; Rosa, G; Russo, A; Savvinov, N; Schembri, A; Lavina, L S; Simone, S; Sioli, M; Sirignano, C; Sirri, G; Strolin, P; Tioukov, V

    2007-01-01

    We have studied the performance of a new algorithm for electron/pion separation in an Emulsion Cloud Chamber (ECC) made of lead and nuclear emulsion films. The software for separation consists of two parts: a shower reconstruction algorithm and a Neural Network that assigns to each reconstructed shower the probability to be an electron or a pion. The performance has been studied for the ECC of the OPERA experiment [1]. The $e/\\pi$ separation algorithm has been optimized by using a detailed Monte Carlo simulation of the ECC and tested on real data taken at CERN (pion beams) and at DESY (electron beams). The algorithm allows to achieve a 90% electron identification efficiency with a pion misidentification smaller than 1% for energies higher than 2 GeV.

  18. Electron/pion separation with an Emulsion Cloud Chamber by using a Neural Network

    NASA Astrophysics Data System (ADS)

    Arrabito, L.; Autiero, D.; Bozza, C.; Buontempo, S.; Caffari, Y.; Consiglio, L.; Cozzi, M.; D'Ambrosio, N.; DeLellis, G.; DeSerio, M.; Di Capua, F.; Di Ferdinando, D.; Di Marco, N.; Ereditato, A.; Esposito, L. S.; Gagnebin, S.; Giacomelli, G.; Giorgini, M.; Grella, G.; Hauger, M.; Ieva, M.; Janicsko Csathy, J.; Juget, F.; Kreslo, I.; Laktineh, I.; Longhin, A.; Mandrioli, G.; Marotta, A.; Marteau, J.; Migliozzi, P.; Monacelli, P.; Moser, U.; Muciaccia, M. T.; Pastore, A.; Patrizii, L.; Pistillo, C.; Pozzato, M.; Romano, G.; Rosa, G.; Russo, A.; Savvinov, N.; Schembri, A.; Scotto Lavina, L.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Strolin, P.; Tioukov, V.

    2007-02-01

    We have studied the performance of a new algorithm for electron/pion separation in an Emulsion Cloud Chamber (ECC) made of lead and nuclear emulsion films. The software for separation consists of two parts: a shower reconstruction algorithm and a Neural Network that assigns to each reconstructed shower the probability to be an electron or a pion. The performance has been studied for the ECC of the OPERA experiment [1]. The e/? separation algorithm has been optimized by using a detailed Monte Carlo simulation of the ECC and tested on real data taken at CERN (pion beams) and at DESY (electron beams). The algorithm allows to achieve a 90% electron identification efficiency with a pion misidentification smaller than 1% for energies higher than 2 GeV.

  19. ESR studies of semicontinuous emulsion polymerization

    SciTech Connect

    Lau, W.; Westmoreland, D.G. [Rohm and Haas Co., Spring House, PA (United States)

    1993-12-31

    Electron spin resonance (ESR) is used in the detection and quantification of propagating radicals during a semicontinuous emulsion polymerization. The propagating radical concentration is crucial for the determination of kinetic parameters of the emulsion polymerization process. A flow reactor was built which involves a closed-loop flow system that circulates latex from the polymerization reactor through the ESR cavity for free-radical measurements and back to the reactor. With the continuous measurement of the radical concentrations during a polymerization of methyl methacrylate (MMA), {bar n} (average number of radicals per particle) and k{sub p} (propagating rate constant), are measured throughout the entire polymerization. For the polymerization of the MMA system studied, the authors observed a gradual increased in n and decrease in k{sub p} during the run, suggesting a diffusionally controlled process and that the polymerization is not occurring homogeneously throughout the polymer particles. In the glassy pMMA matrix, radicals can be {open_quotes}trapped{close_quotes} within a minimum volume and remain unterminated.

  20. Metabolic effects of intravenous LCT or MCT\\/LCT lipid emulsions in preterm infants

    Microsoft Academic Search

    Frauke Lehner; Hans Demmelmair; Wulf Roschinger; Tamas Decsi; Maria Szasz; Karoly Adamovich; Ralf Arnecke; Berthold Koletzko

    2005-01-01

    Most lipid emulsions for parenteral feeding of premature infants are based on long-chain triacylglycerols (LCTs), but inclusion of medium-chain triacylglycerols (MCTs) might provide a more readily oxidizable energy source. The influence of these emulsions on fatty acid com- position and metabolism was studied in 12 premature neo- nates, who were randomly assigned to an LCT emulsion (control) or an emulsion

  1. Equilibrium and Nonequilibrium States in Microfluidic Double Emulsions Nicolas Pannacci,1

    E-print Network

    Weeks, Eric R.

    Equilibrium and Nonequilibrium States in Microfluidic Double Emulsions Nicolas Pannacci,1 Henrik.55.db, 47.57.jb, 68.05.Cf Double emulsions (i.e., emulsions in which the dis- persed phase is also an emulsion) are of considerable interest in food, cosmetic industries, medical sciences (drug delivery

  2. Research of inverted emulsions properties on the base of new emulsifiers

    NASA Astrophysics Data System (ADS)

    Minaev, K.; Epikhin, A.; Novoseltsev, D.; Andropov, M.; Yanovsky, V.; Ulyanova, O.

    2014-08-01

    Emulsifiers on the base of tallol and ethanolamines derived acids have been researched in the paper. Electrical stability of emulsions drilling muds has been investigated. It is proved that synthesized emulsifiers according to emulsion stability can be divided into two groups. The first group is emulsifiers with high initial electrical stability but low emulsion stability under long-term storing, and the second group is emulsifiers with low electrical stability but with high emulsion stability. Emulsions flow characteristics have been researched. It is established that emulsifier on the base of ethanolamine provides better emulsion characteristics for drilling muds emulsions.

  3. Importance of grafting in the emulsion polymerization of MMA using PVA as a protective colloid. Effect of initiators

    Microsoft Academic Search

    Takuji Okaya; Atsushi Suzuki; Kenji Kikuchi

    1999-01-01

    To clarify the initial stage of particle formation in the emulsion polymerization of methyl methacrylate (MMA) using poly(vinyl alcohol) (PVA) as a protective colloid, a model experiment with a low concentration of MMA (1 ml\\/100 ml H2O) was carried out in the presence of various initiators, ammonium persulfate (APS), 2,2?-azobis(2-amidinopropane)dihydrochloride (V-50) and 2,2?-azobis (isobutyronitrile) (AIBN). In the experiments using a

  4. Factors that affect Pickering emulsions stabilized by graphene oxide.

    PubMed

    He, Yongqiang; Wu, Fei; Sun, Xiying; Li, Ruqiang; Guo, Yongqin; Li, Chuanbao; Zhang, Lu; Xing, Fubao; Wang, Wei; Gao, Jianping

    2013-06-12

    Stable Pickering emulsions were prepared using only graphene oxide (GO) as a stabilizer, and the effects of the type of oil, the sonication time, the GO concentration, the oil/water ratio, and the pH value on the stability, type, and morphology of these emulsions were investigated. In addition, the effects of salt and the extent of GO reduction on emulsion formation and stability were studied and discussed. The average droplet size decreased with sonication time and with GO concentration, and the emulsions tended to achieve good stability at intermediate oil/water ratios and at low pH values. In all solvents, the emulsions were of the oil-in-water type, but interestingly, some water-in-oil-in-water (w/o/w) multiple emulsion droplets were also observed with low GO concentrations, low pH values, high oil/water ratios, high salt concentrations, or moderately reduced GO in the benzyl chloride-water system. A Pickering emulsion stabilized by Ag/GO was also prepared, and its catalytic performance for the reduction of 4-nitrophenol was investigated. This research paves the way for the fabrication of graphene-based functional materials with novel nanostructures and microstructures. PMID:23647467

  5. Mechanical characterization of diblock copolymer ``armored'' emulsion droplets

    NASA Astrophysics Data System (ADS)

    Rozairo, Damith P.; Croll, Andrew B.

    2013-03-01

    There has been an increased interest in block copolymer vesicles due to a plethora of possible application ranging from targeted drug delivery to cosmetically active agents. In this regard, understanding the physics of the block copolymer vesicle and its morphology is critical to the rational development of these technologies. As a step towards more complex vesicle structures, we describe experiments in which we carefully examine the interface and morphology of polystyrene-b-polyethyleneoxide (PS-PEO) emulsion drops. In our study, PS-PEO acts as a surfactant and at the toluene-water interface creates a monolayer, inhibiting drop recombination and minimizing interfacial energies. Our experiments are conducted in a water cell where the buoyant force is exploited to push drops against a thin sheet of mica. The shape of the drops is measured using an upright confocal microscope and compared with a Bashforth-Adams model in order to examine the mechanical response to the buoyant force. We observe unique dynamics as the drops buckle at short timescales trapping a small pocket of fluid which slowly drains away. Furthermore, the influence of polymer concentration, changes in pH and block copolymer architecture on the morphology and dynamics of the droplets is examined.

  6. Physical properties and stability of two emulsion formulations of propofol.

    PubMed

    Han, J; Davis, S S; Washington, C

    2001-03-14

    We have compared the physical properties of two commercial emulsion formulations of the intravenous anaesthetic propofol, (Diprivan, AstraZeneca, and Propofol Intravenous Emulsion, Gensia Sicor Pharmaceuticals) which appear to differ primarily in the additive content and formulation pH. Diprivan contains disodium edetate and has a pH of 7-8.5, while the Gensia product contains sodium metabisulphite and is formulated to a pH of 4.5-6.4. The average zeta potential of Diprivan at pH 8 was -50 mV while that of the Gensia product at pH 4-5 was -40 mV. This information suggests that the physical stability of Propofol Intravenous Emulsion should be lower than that of Diprivan. Three random batches of both products were subjected to a range of stability tests, including shaking, thermal cycling, and freeze-thaw cycling, and the emulsion droplet size distribution was then assessed by dynamic light scattering, light diffraction, and electrical and optical zone sensing. Both emulsions initially showed narrow submicrometre particle size distributions. An increased level of droplets larger than 5 microm could be detected in Propofol Intravenous Emulsion after as little as 4 h shaking (300 strokes/min at room temperature) and visible free oil could be detected after 8-12 h shaking. In contrast, Diprivan showed no increase in the large droplet count after shaking for times up to 16 h. A similar difference in the emulsions was found after one freeze-thaw cycle, with Propofol Intravenous Emulsion exhibiting extensive coalescence, while that of Diprivan was at the limits of detection. We conclude that these two products have different physical stability characteristics, and that this may in part be due to the reduced zeta potential in Propofol Intravenous Emulsion compared to that of Diprivan. PMID:11250106

  7. Freeze\\/thaw induced demulsification of water-in-oil emulsions with loosely packed droplets

    Microsoft Academic Search

    Chang Lin; Gaohong He; Xiangcun Li; Lin Peng; Chunxu Dong; Shuang Gu; Gongkui Xiao

    2007-01-01

    Freeze\\/thaw treatment has been widely investigated for phase separation of oil-in-water (O\\/W) emulsions. However, it is a new application for destroying the inverted emulsions, water-in-oil (W\\/O) emulsions. In this study, freeze\\/thaw treatment was used to break the W\\/O emulsions with loosely packed droplets that were produced from the oils generally adopted as membrane phase in emulsion liquid membrane (ELM) process.

  8. Automatic scanning of nuclear emulsions with wide-angle acceptance for nuclear fragment detection

    E-print Network

    T. Fukuda; S. Fukunaga; H. Ishida; K. Kodama; T. Matsuo; S. Mikado; S. Ogawa; H. Shibuya; J. Sudo

    2013-01-09

    Nuclear emulsion, a tracking detector with sub-micron position resolution, has played a successful role in the field of particle physics and the analysis speed has been substantially improved by the development of automated scanning systems. This paper describes a newly developed automated scanning system and its application to the analysis of nuclear fragments emitted almost isotropically in nuclear evaporation. This system is able to recognize tracks of nuclear fragments up to |tan{\\theta}|emulsion film), while existing systems have an angular acceptance limited to |tan{\\theta}|emulsion is the first trial. Furthermore the track recognition algorithm is performed by a powerful Graphics Processing Unit (GPU) for the first time. This GPU has a sufficient computing power to process large area scanning data with a wide angular acceptance and enough flexibility to allow the tuning of the recognition algorithm. This new system will in particular be applied in the framework of the OPERA experiment : the background in the sample of tau decay candidates due to hadronic interactions will be reduced by a better detection of the emitted nuclear fragments.

  9. Anti-fouling effect of bentonite suspension in ultrafiltration of oil/water emulsion.

    PubMed

    Panpanit, S; Visvanathan, C; Muttamara, S

    2002-03-01

    The effect on membrane fouling resistance during ultrafilration of oil/water emulsion with the presence of bentonite suspension is experimentally evaluated. The fouling resistance was analyzed as a function of different membrane types and bentonite concentration. The total membrane fouling was categorized into reversible and irreversible, by adopting an appropriate chemical cleaning technique. The results revealed a 40% flux augmentation with the increase of bentonite concentration up to an optimum value of 300 mg l(-1) for cellulose acetate membrane. Further increase of bentonite concentration led to particle deposition on the membrane surface and reduced the flux. The polysulfone membrane did not show a similar flux improvement. This could be due to its high hydrophobicity. The absorption of oil/water emulsion on bentonite increased TOC removal rate from 65% to 80%, and this effect was the major cause of reduction in gel layer formation on the membrane surface. The extent of irreversible fouling of the hydrophilic cellulose acetate membrane was much smaller than that of the polysulfone membrane. These experiments demonstrated that, presence of bentonite could induce transformation of irreversible fouling caused by oil emulsion to reversible fouling, which could be periodically chemically cleaned. PMID:11999987

  10. Further progress for a fast scanning of nuclear emulsions with Large Angle Scanning System

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Tioukov, V.; Vladymyrov, M.

    2014-02-01

    The LASSO (Large Angle Scanning System for OPERA) is a scanning system designed in the framework of the OPERA experiment as a result of several R&Ds aimed to improve the performance of the European Scanning System (ESS) by increasing the scanning speed, the angular acceptance and the efficiency in microtrack reconstruction. The novel Continuous Motion (CM) scanning approach allows to double the ESS nominal speed without any changes in the hardware set-up. The LASSO modular design makes the system easily adaptable to new hardware. The novel microtrack reconstruction algorithm has been developed to be efficient in both standard Stop&Go (SG) and CM modes, performing a number of corrections during the processing like corrections for vibrations, optical distortions, field of view curvature. As an intermediate step it reconstructs silver grains positions inside emulsion layer to make a transition from 2D images to real 3D traces of a charged particle. This allows the algorithm to have no internal limits on the slope of microtracks being equally efficient on all angles. The LASSO has been used for about one year for mass production scanning of emulsion films of OPERA, Muon Radiography and also of films employed to study nuclear fragmentation of ion beams used in medical physics. More than 50000 cm2 of the emulsion surface have been analyzed during this period.

  11. Temperature dependence of emulsion morphologies and the dispersion morphology diagram. 2. Three-phase emulsions

    SciTech Connect

    Smith, D.H.; Johnson, G.K. [Morgantown Energy Technology Center, WV (United States)

    1995-07-06

    Using several different compositions of the (pseudo)ternary amphiphile/oil/`water` system C{sub 6}H{sub 13}(OC{sub 2}H{sub 4}){sub 2}-OH/n-tetradecane/aqueous 10 mM NaCl, we show by means of electrical conductivity measurements that the temperature dependencies of the emulsion morphologies were consistent with predictions from isothermal dispersion morphology diagrams, thus contradicting phase inversion temperature ideas. 26 refs., 8 figs.

  12. Anisotropy of magnetic emulsions induced by magnetic and electric fields

    E-print Network

    Yury I. Dikansky; Alexander N. Tyatyushkin; Arthur R. Zakinyan

    2011-09-10

    The anisotropy of magnetic emulsions induced by simultaneously acting electric and magnetic fields is theoretically and experimentally investigated. Due to the anisotropy, the electric conductivity and magnetic permeability of a magnetic emulsion are no longer scalar coefficients, but are tensors. The electric conductivity and magnetic permeability tensors of sufficiently diluted emulsions in sufficiently weak electric and magnetic fields are found as functions of the electric and magnetic intensity vectors. The theoretically predicted induced anisotropy was verified experimentally. The experimental data are analyzed and compared with theoretical predictions. The results of the analysis and comparison are discussed.

  13. Water-in-Crude Oil Emulsion Stability Investigation

    Microsoft Academic Search

    Mamdouh T. Ghannam

    2005-01-01

    The water-in-crude oil emulsion has great importance in the oil industry. The stability of water-in-crude oil emulsion is investigated over a wide range of parameters. These parameters are water concentration (10–50%), surfactant concentration (0.1–1%), mixing speed (500–2, 000 rpm), salt concentration (0–5%), polymer concentration (0–1, 000 ppm), and temperature (13–40C). The physical properties of water-in-crude oil emulsion in terms of density, viscosity,

  14. Factors controlling the stability of colloid-stabilized emulsions

    SciTech Connect

    Tambe, D.E.; Sharma, M.M. (Univ. of Texas, Austin (United States))

    1993-04-01

    Experimental data are presented to show the influence of colloidal particles on the stability of oil-water emulsions. It is shown that these solids stabilize emulsions both by providing steric hindrance to drop-drop coalescence and by modifying the rheological properties of the interfacial region. Coalescence occurs as a result of the displacement of the colloids along the interface. Results are presented on the effects of pH and salt concentration in the aqueous phase, the concentration of surfactant in the oleic phase, and the properties of the solid particles on the type and the stability of emulsions formed.

  15. Nuclear Emulsion Film Detectors for Proton Radiography:. Design and Test of the First Prototype

    NASA Astrophysics Data System (ADS)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Moser, U.; Pistillo, C.; Studer, S.; Scampoli, P.

    2010-04-01

    Proton therapy is nowadays becoming a wide spread clinical practice in cancer therapy and sophisticated treatment planning systems are routinely used to exploit at best the ballistic properties of charged particles. The information on the quality of the beams and the range of the protons is a key issue for the optimization of the treatment. For this purpose, proton radiography can be used in proton therapy to obtain direct information on the range of the protons, on the average density of the tissues for treatment planning optimization and to perform imaging with negligible dose to the patient. We propose an innovative method based on nuclear emulsion film detectors for proton radiography, a technique in which images are obtained by measuring the position and the residual range of protons passing through the patient's body. Nuclear emulsion films interleaved with tissue equivalent absorbers can be fruitfully used to reconstruct proton tracks with very high precision. The first prototype of a nuclear emulsion based detector has been conceived, constructed and tested with a therapeutic proton beam at PSI. The scanning of the emulsions has been performed at LHEP in Bern, where a fully automated microscopic scanning technology has been developed for the OPERA experiment on neutrino oscillations. After track reconstruction, the first promising experimental results have been obtained by imaging a simple phantom made of PMMA with a step of 1 cm. A second phantom with five 5 × 5 mm2 section aluminum rods located at different distances and embedded in a PMMA structure has been also imaged. Further investigations are in progress to improve the resolution and to image more sophisticated phantoms.

  16. Temperature dependence of emulsion morphologies and the dispersion morphology diagram for three-phase emulsions

    SciTech Connect

    Smith, D.H.; Johnson, G.K. [Morgantown Energy Technology Center, WV (United States)

    1995-12-31

    Using several different compositions of the (pseudo)ternary amphiphile/oil/{open_quotes}water{close_quotes} system C{sub 6}H{sub 13}(OC{sub 2}H{sub 4}){sub 2}OH/n-tetradecane/aqueous 10 mM NaCl that form oil-rich top phases (J), water-rich bottom phases ({Beta}), and middle-phase microemulsions (m), we showed by means of electrical conductivity measurements that the temperature dependencies of the three-phase emulsion morphologies were consistent with predictions from isothermal dispersion morphology diagrams, thus contradicting ideas derived from the PIT (phase inversion temperature) model for two-phase emulsions. In particular, we formed three-phase emulsions in which either (1) the continuous phase was an oil-rich phase (actually, m) below the PIT and the water-rich phase ({Beta}) above that temperature; (2) the water-rich phase was continuous both below and above the PIT; or (3) oil-rich phase was the continuous phase both below and above the PIT.

  17. Low momentum particle detector for the NA61 experiment at CERN

    NASA Astrophysics Data System (ADS)

    Márton, Krisztina; Kiss, Gábor; László, András; Varga, Dezs?

    2014-11-01

    The NA61 Experiment at CERN SPS is a large acceptance hadron spectrometer, aimed to studying hadron-hadron, hadron-nucleus, and nucleus-nucleus interactions in a fixed target environment. The present paper discusses the construction and performance of the Low Momentum Particle Detector (LMPD), a small time projection chamber unit which has been added to the NA61 setup in 2012. The LMPD considerably extends the detector acceptance towards the backward region, surrounding the target in hadron-nucleus interactions. The LMPD features simultaneous range and ionization measurements, which allows for particle identification and momentum measurement in the 0.1-0.25 GeV/c momentum range for protons. The possibility of Z=1 particle identification in this range is directly demonstrated.

  18. Low Momentum Particle Detector for the NA61 Experiment at CERN

    E-print Network

    K. Marton; G. Kiss; A. Laszlo; D. Varga

    2014-06-11

    The NA61 Experiment at CERN SPS is a large acceptance hadron spectrometer, aimed to studying of hadron-hadron, hadron-nucleus, and nucleus-nucleus interactions in a fixed target environment. The present paper discusses the construction and performance of the Low Momentum Particle Detector (LMPD), a small time projection chamber unit which has been added to the NA61 setup in 2012. The LMPD considerably extends the detector acceptance towards the backward region, surrounding the target in hadron-nucleus interactions. The LMPD features simultaneous range and ionization measurements, which allows for particle identification and momentum measurement in the 0.1-0.25 GeV/c momentum range for protons. The possibility of Z=1 particle identification in this range is directly demonstrated.

  19. Bacterial imprinting at Pickering emulsion interfaces.

    PubMed

    Shen, Xiantao; Svensson Bonde, Johan; Kamra, Tripta; Bülow, Leif; Leo, Jack C; Linke, Dirk; Ye, Lei

    2014-09-26

    The tendency of bacteria to assemble at oil-water interfaces can be utilized to create microbial recognition sites on the surface of polymer beads. In this work, two different groups of bacteria were first treated with acryloyl-functionalized chitosan and then used to stabilize an oil-in-water emulsion composed of cross-linking monomers that were dispersed in aqueous buffer. Polymerization of the oil phase followed by removal of the bacterial template resulted in well-defined polymer beads bearing bacterial imprints. Chemical passivation of chitosan and cell displacement assays indicate that the bacterial recognition on the polymer beads was dependent on the nature of the pre-polymer and the target bacteria. The functional materials for microbial recognition show great potential for constructing cell-cell communication networks, biosensors, and new platforms for testing antibiotic drugs. PMID:25111359

  20. Stability of cellulose lyotropic liquid crystal emulsions

    NASA Astrophysics Data System (ADS)

    Tixier, T.; Heppenstall-Butler, M.; Terentjev, E. M.

    2005-12-01

    We studied a new kind of W/O emulsions based on a lyotropic liquid crystal as the aqueous droplet phase. The cholesteric phase, a solution hydroxypropyl cellulose in water was dispersed in the continuous oil matrix, paraffin oil or heptane. We made a specific choice of surfactant in order to impose director anchoring conditions at the oil-water interface and orient the liquid crystal inside the droplet. The strong anchoring conditions resulted in a topological defect inside the droplets of size above the critical value R^*. The defect elastic energy creates a barrier against droplet coalescence, the effect of topological size selection. We have studied the orientation of the director inside the droplets and their size distribution.

  1. Magnetically Recoverable Efficient Demulsifier for Water-in-Oil Emulsions.

    PubMed

    Chen, Yuning; Lin, Xin; Liu, Na; Cao, Yingze; Lu, Fei; Xu, Liangxin; Feng, Lin

    2015-02-23

    A magnetically recoverable and efficient demulsifier is shown to demulsify surfactant-stable water-in-oil emulsions rapidly. Ferroferric oxide (Fe3 O4 ) particles are firstly coated by amorphous silicon dioxide (SiO2 ), and further functionalized with a commercial dodecyltrimethoxysilane solution (KH-1231). Owing to their paramagnetic properties, the demulsifier particles can be easily recovered with a magnet. Upon addition of demulsifier to emulsions and subsequent sonification, the supernatant becomes completely transparent and no droplets are observed in the micrographs. It was also demonstrated that this demulsifier is effective for emulsions prepared with a variety of oils. Moreover, magnetically recovered demulsifier can be recycled after simple treatment without any decline of efficiency. This work presents a feasible approach for demulsifying water-in-oil emulsions, and has potential value in industry. PMID:25504588

  2. Emulsion Polymerization of Butyl Acrylate: Spin Trapping and EPR Study

    NASA Technical Reports Server (NTRS)

    Kim, S.; Westmoreland, D.

    1994-01-01

    The propagating radical in the emulsion polymerization reaction of butyl acrylate was detected by Electron Paramagnetic Resonance spectroscopy using two spin trapping agents, 2-methyl-2nitrosopropane and alpha -N-tert-butylnitrone.

  3. Water-in-carbon dioxide emulsions: Formation and stability

    SciTech Connect

    Lee, C.T. Jr.; Psathas, P.A.; Johnston, K.P.; Grazia, J. de; Randolph, T.W.

    1999-09-28

    Stable water-in-carbon dioxide (W/C) emulsions, for either liquid or supercritical CO{sub 2} containing up to 70 vol % water, are formed with various molecular weight perfluoropolyether ammonium caroxylate surfactants. Water droplet sizes ranging from 3 to 10 {micro}m were determined by optical microscopy. From conductivity measurements, an inversion to C/W emulsions results from a decrease in CO{sub 2} density or salinity at constant pressure, a decrease in surfactant molecular weight, or an increase in temperature. Emulsions become more stable with a change in any of these formulation variables away from the balanced state, which increases interfacial tensions and interfacial tension gradient enhancing Marangoni-Gibbs stabilization. This type of stability is enhanced with an increase in the molecular weight of the surfactant tails, which increases the thickness of the stabilizing films between droplets. W/C emulsions formed with the 7,500 molecular weight surfactant were stable for several days.

  4. Fluorescent-magnetic Janus particles prepared via seed emulsion polymerization.

    PubMed

    Kaewsaneha, Chariya; Bitar, Ahmad; Tangboriboonrat, Pramuan; Polpanich, Duangporn; Elaissari, Abdelhamid

    2014-06-15

    Anisotropic polymeric colloidal or Janus particles possessing simultaneous magnetic and fluorescent properties were successfully prepared via the swelling-diffusion or the in situ emulsion polymerization method. In the swelling-diffusion process, magnetic emulsions (an organic ferrofluid dispersed in aqueous medium) were synthesized and used for seeds of submicron magnetic Janus particles. After swelling the anisotropic particles obtained by 1-pyrene-carboxaldehyde fluorescent dye dissolved in tetrahydrofuran, well-defined fluorescent-magnetic Janus particles were produced. In the in situ emulsion polymerization, styrene monomer mixed with fluorescent dye monomers, i.e., 1-pyrenylmethyl methacrylate (PyMMA) or fluorescein dimethacrylate (FDMA), and an oil-soluble initiator (2,2'-azobis(2-isobutyronitrile)) were emulsified in the presence of magnetic seed emulsions. The confocal microscopic images showed the fluorescent-magnetic Janus particles with high fluorescent intensity when a fluorescent crosslinker monomer FDMA was employed. PMID:24767504

  5. Chemical Demulsification of Water-in-Crude Oil Emulsions

    NASA Astrophysics Data System (ADS)

    Abdurahman; Nour, H.; Mohd Yunus, Rosli; Jemaat, Zulkifly

    Demulsification (emulsion breaking) is necessary in many practical applications such as the petroleum industry, painting and waste-water treatment in environmental technology. Chemical demulsification is the most widely applied method of treating water-in-crude oil emulsions and involves the use of chemical additives to accelerate the emulsion breaking process. The effect of chemical demulsification operations on the stability and properties of water-in-crude oil emulsions was assessed experimentally. In this regard, Amine Demulsifier, Polyhydric Alcohol, Acid and Polymeric demulsifiers were used. Using samples of w/o, the data presented for several commercial-type demulsifiers show a strong connection (correlation) between good performance (fast coalescence) and the demulsifiers. The relative rates of water separation were characterized via beaker tests. The amine group demulsifiers promoted best coalescence of droplets. In contrast, polymeric demulsifier group is the least in water separation.

  6. Dehydration of oil waste emulsions by means of flocculants

    SciTech Connect

    Gandurina, L.V.; Butseva, L.N.; Shtondina, V.S.

    1995-05-01

    Oil waste emulsions are formed in the course of pumping petroleum crudes and products and are collected from the surfaces of equipment in recirculating water systems and wastewater disposal facilities (oil separators, sand traps, oil traps, holding pits for accidental spills, settlers, ponds, sludge accumulators, and so on). Emulsions are also obtained in the course of cleaning equipment in crude oil desalting and dehydration units. Such emulsions are stable, structurized systems that are very resistant to dewatering by heating and settling in separator tanks. In order to break stabilized emulsions, i.e., in order to ensure complete coalescence of drops when they collide, it is not sufficient to increase the forces of mutual attraction of drops at the moment of collision; in addition, the protective shell must be either destroyed or weakened. Demulsifying agents, or surfactants, will displace the stabilizers. This report is concerned with demulsifier efficiency.

  7. Stabilizing oil-in-water emulsions with regenerated chitin nanofibers.

    PubMed

    Zhang, Ying; Chen, Zhigang; Bian, Wenyang; Feng, Li; Wu, Zongwei; Wang, Peng; Zeng, Xiaoxiong; Wu, Tao

    2015-09-15

    Natural chitin is a highly crystalline biopolymer with poor aqueous solubility. Thus direct application of chitin is rather limited unless chemical modifications are made to improve its solubility in aqueous media. Through a simple dissolution and regeneration process, we have successfully prepared chitin nanofibers with diameters around 50nm, which form a stable suspension at concentrations higher than 0.50% and a self-supporting gel at concentrations higher than 1.00%. Additionally, these nanofibers can stabilize oil-in-water emulsions with oil fraction more than 0.50 at chitin usage level of 0.01g/g oil. The droplet sizes of the resulting emulsions decrease with increasing chitin concentrations and decreasing oil fraction. Confocal laser scanning micrographs demonstrate the adsorption of chitin nanofibers on the emulsion droplet surface, which indicates the emulsion stabilization is through a Pickering mechanism. Our findings allow the direct application of chitin in the food industry without chemical modifications. PMID:25863618

  8. In vivo handling and metabolism of lipid emulsions.

    PubMed

    Carpentier, Yvon A; Deckelbaum, Richard J

    2015-01-01

    While a number of pathways for the catabolism and tissue delivery of intravenous lipid emulsions are shared by chylomicrons, there are also important differences. The introduction of medium-chain triglycerides (MCTs) and n-3 fatty acid-containing fish oils into lipid emulsions has marked effects on their clearance from the bloodstream and the delivery of fatty acids to organs, and it involves pathways different from those required for n-6 fatty acid-rich soybean oil-based particles. 1) Multiple pathways are responsible for the blood clearance and tissue uptake of MCT- and fish oil-containing emulsions. 2) Both human and animal model-based studies were needed to define these 'classical' and 'novel' pathways, which are respectively similar to and different from those involved in chylomicron clearance. 3) n-3 fatty acid-rich triglycerides and MCTs provide new opportunities for lipid emulsions to act as metabolic and immune modulators. PMID:25471802

  9. Relation between viscosity and stability for heavy oil emulsions

    E-print Network

    Ye, Sherry Qianwen

    1998-01-01

    The relation between viscosity and stability has been hics. found by investigating the effect of surfactant concentration on emulsion stability. Based on the Bingham plastic model for viscosity as a function of shear rate, two parameters were found...

  10. Stability and demulsification of emulsions stabilized by asphaltenes or resins.

    PubMed

    Xia, Lixin; Lu, Shiwei; Cao, Guoying

    2004-03-15

    Experimental data are presented to show the influence of asphaltenes and resins on the stability and demulsification of emulsions. It was found that emulsion stability was related to the concentrations of the asphaltene and resin in the crude oil, and the state of dispersion of the asphaltenes and resins (molecular vs colloidal) was critical to the strength or rigidity of interfacial films and hence to the stability of the emulsions. Based on this research, a possible emulsion minimization approach in refineries, which can be implemented utilizing microwave radiation, is also suggested. Comparing with conventional heating, microwave radiation can enhance the demulsification rate by an order of magnitude. The demulsification efficiency reaches 100% in a very short time under microwave radiation. PMID:14972628

  11. Modular ‘Click-in-Emulsion’ Bone-Targeted Nanogels

    E-print Network

    Heller, Daniel A.

    A new class of nanogel demonstrates modular biodistribution and affinity for bone. Nanogels, ~70 nm in diameter and synthesized via an astoichiometric click-chemistry in-emulsion method, controllably display residual, free ...

  12. Nanostructured carbon-metal oxide hybrids as amphiphilic emulsion catalysts.

    PubMed

    Ruiz, M Pilar; Faria, Jimmy; Shen, Min; Drexler, Santiago; Prasomsri, Teerawit; Resasco, Daniel E

    2011-07-18

    Nanohybrids composed of "onion-like" carbon, single-walled (SWCNTs) or multi-walled carbon nanotubes (MWCNTs) fused to silica or alumina particles have been compared as stabilizers of water/oil emulsions and interfacial catalysts. The amphiphilic character of these nanohybrids makes them effective in stabilizing emulsions (up to 85?% of total volume) comprising of small droplets (less than 40 ?m). Furthermore, these nanohybrids have been used as supports for transition metal particles (palladium and copper) to catalyze reactions at the water/oil interface. Three different reaction systems have been conducted in the emulsions to demonstrate the principle: 1) hydrogenation of phenanthrene; 2) hydrogenation of glutaraldehyde and benzaldehyde; 3) oxidation of tetralin. Comparison of the maximum conversions achieved in emulsions as opposed to the single phase, together with much better control of selectivity in the two-phase system shows the benefits of using these nanohybrid catalysts. PMID:21751419

  13. Nuclear emulsion with molybdenum filling for observation of $??$ decay

    E-print Network

    V. D. Ashitkov; A. V. Bagulya; A. S. Barabash; V. Ya. Bradnova; M. M. Chernyavsky; S. I. Konovalov; N. M. Okat'eva; G. I. Orlova; N. G. Polukhina; E. A. Pozharova; V. A. Smirnitsky; N. I. Starkov; M. S. Vladimirov; V. I. Umatov

    2010-02-15

    The usage of nuclear emulsion with molybdenum filling for observation of $\\beta\\beta$ decay are shown to be possible. Estimates for 1 kg of $^{100}$Mo with zero background give the sensitivity for the $0\

  14. Hydrophobins stabilised air-filled emulsions for the food industry

    Microsoft Academic Search

    F. L. Tchuenbou-Magaia; I. T. Norton; P. W. Cox

    2009-01-01

    Hydrophobin HFBII has been extracted from a culture of Trichoderma reesei. The protein has been used to construct air cells of approximately 1–100 ?m in size, with approximately 40% of the air cells falling within the 1–2 ?m range. We have termed these suspensions air-filled emulsions and propose their use for fat replacement in emulsion based food structures. The air cells in

  15. Our current understanding of water-in-crude oil emulsions

    Microsoft Academic Search

    Johan Sjöblom; Narve Aske; Inge Harald Auflem; Øystein Brandal; Trond Erik Havre; Øystein Sæther; Arild Westvik; Einar Eng Johnsen; Harald Kallevik

    2003-01-01

    Stable water-in-oil emulsions may form during the production of crude oil, as co-produced water is mixed with the oil from reservoir to separation facilities. Such emulsions introduce technical challenges, as they must be resolved to provide the specified product quality. Asphaltenes and resins indigenous to the oil are acknowledged as the most important components in respect to stabilization of the

  16. Fat crystals and water-in-oil emulsion stability

    Microsoft Academic Search

    Supratim Ghosh; Dérick Rousseau

    2011-01-01

    Products such as cosmetics, pharmaceuticals, and crude oil often exist as water-in-oil (W\\/O) emulsions during their processing or in final form. In many cases, their dispersed aqueous phase is encased in a crystal network and\\/or by interfacially-adsorbed (‘Pickering’) particles [paraffins, triacylglycerols, polymers, etc.] that promote emulsion kinetic stability by hindering droplet–droplet contact, coalescence and macroscopic phase separation. In processed foods,

  17. Study of formulation and stability of emulsions with polymeric emulsifiers

    Microsoft Academic Search

    Marie-France Bobin; Valérie Michel; Marie-Claude Martini

    1999-01-01

    Polymeric emulsifiers have appeared recently and have got emulsifying and thickness properties. These emulsifiers provide exceptional stability to oil-in-water-emulsions. This study shows formulations of new emulsifiers. The polymeric emulsifiers used were acrylate C10–C30 alkyl–acrylate cross polymer (Tr1–Tr2). They provide exceptional stability to oil-in-water emulsions at very low usage levels (0.1,0.3%), they can be used with any oil phase, easily prepared

  18. Design of double emulsions by osmotic pressure tailoring.

    PubMed

    Mezzenga, Raffaele; Folmer, Britta M; Hughes, Eric

    2004-04-27

    A method was developed allowing in situ adjustment of water-in-oil-in-water double emulsion (W/O/W) morphologies by tailoring the osmotic pressure of the water phases. The control of internal droplet size is achieved by altering the chemical potential of the external and internal water phases by dissolving neutral linear polysaccharides of suitable molecular weights. As a consequence of the different chemical potentials in the two aqueous phases, transport of water takes place modifying the initial morphology of the double emulsion. Self-diffusion 1H nuclear magnetic resonance (1H NMR) was used to assess transport mechanisms of water in oil, while a numerical model was developed to predict the swelling/shrinking behavior of W/O/W double emulsions. The model was based on a two-step procedure in which the equilibrium size of a single internal water droplet was first predicted and then the results of the single droplet were extended to the entire double emulsion. The prediction of the equilibrium size of an internal droplet was derived by the equalization of the Laplace pressure with the osmotic pressure difference of the two aqueous phases, as modeled by mean-field theory. The double emulsion equilibrium morphologies were then predicted by upscaling the results of a single drop to the droplet size distribution of the internal W/O emulsion. Good agreement was found between the theoretical predictions and the measurement of double emulsion droplet size distribution. Therefore, the present model constitutes a valuable tool for in situ control of double emulsion morphology and enables new possible applications of these colloidal systems. PMID:15875386

  19. Mechanism of detonation of emulsion explosives with microballoons

    Microsoft Academic Search

    A. E. Medvedev; V. M. Fomin; A. Yu. Reshetnyak

    2008-01-01

    A mechanism of detonation of emulsion explosives containing microballoons in finite-diameter charges is described. A parametric\\u000a dependence of the detonation velocity on the charge characteristics is obtained. The fact that the reaction-zone width increases\\u000a with decreasing charge porosity is explained. It is shown that the emulsion does not completely burn out at the Chapman-Jouguet\\u000a point. Final formulas for calculating the

  20. Development of Large Area Emulsion Chamber Methods with a Super Conducting Magnet for Observation of Cosmic Ray Nuclei from 1 GeV to 1,000 TeV (Emulsion Techniques)

    NASA Technical Reports Server (NTRS)

    Takahashi, Yoshiyuki; Gregory, John C.; Tominaga, Taka; Dong, Bei Lei

    1997-01-01

    The research developed the fundamental techniques of the emulsion chamber methods that permit measurements of the composition and energy spectra of cosmic rays at energies ranging from 1 GeV/n to over 1,000 TeV/n. The research program consisted of exploring new principles and techniques in measuring very high energy cosmic nuclei with large-area emulsion chambers for high statistics experiments. These tasks have been accomplished and their use was essential in successful analysis of the balloon-borne emulsion chamber experiments up to 10(exp 14) eV. It also provided the fundamental technologies for designing large-area detectors that are aimed at measuring the composition at above 1015 eV region. The latter is now partially succeeded by a NASA Mission Concept, Advanced Cosmic Composition Experiments on the Space Station (ACCESS). The cosmic ray group at the University of Alabama in Huntsville has performed technological R & D as well as contributing to the Japanese-American-Emulsion-Chamber-Experiments (JACEE) Collaboration with the regular data analysis. While primary research support for other institutions' efforts in the JACEE experiments came from NSF and DOE, primary support for the University of Alabama in Huntsville was this contract. Supplemental tasks to standardize the data base and hardware upgrades (automatized microscope) had this institutions cooperation. Investigation of new techniques in this program consisted of development of a fast calorimetry, magnetic/scattering selection of high momentum tracks for a pairmeter, and high statistics momentum measurements for low energy nuclei (E < 1 TeV/n). The highest energy calorimetry and a pairmeter have been considered as strawman instruments by the GOAL (Galactic Origin and Acceleration Limit) proposal of the NASA Cosmic Ray Working Group for long- duration balloon flights. We accomplished the objectives of the GOAL program with three circumpolar, Antarctic JACEE balloon flights during 1992 - 1994.

  1. Timescales of emulsion formation caused by anisotropic particles.

    PubMed

    Günther, Florian; Frijters, Stefan; Harting, Jens

    2014-07-21

    Particle stabilized emulsions have received much interest in the recent past, but our understanding of the dynamics of emulsion formation is still limited. For simple spherical particles, the time dependent growth of fluid domains is dominated by the formation of droplets, particle adsorption and coalescence of droplets (Ostwald ripening), which eventually can be almost fully blocked due to the presence of the particles. Ellipsoidal particles are known to be more efficient stabilizers of fluid interfaces than spherical particles and their anisotropic shape and the related additional rotational degrees of freedom have an impact on the dynamics of emulsion formation. In this paper, we investigate this point by means of simple model systems consisting of a single ellipsoidal particle or a particle ensemble at a flat interface as well as a particle ensemble at a spherical interface. By applying combined multicomponent lattice Boltzmann and molecular dynamics simulations we demonstrate that the anisotropic shape of ellipsoidal particles causes two additional timescales to be of relevance in the dynamics of emulsion formation: a relatively short timescale can be attributed to the adsorption of single particles and the involved rotation of particles towards the interface. As soon as the interface is jammed, however, capillary interactions between the particles cause a local reordering on very long timescales leading to a continuous change in the interface configuration and increase of the interfacial area. This effect can be utilized to counteract the thermodynamic instability of particle stabilized emulsions and thus offers the possibility to produce emulsions with exceptional stability. PMID:24888563

  2. Droplet-based microfluidics and the dynamics of emulsions

    NASA Astrophysics Data System (ADS)

    Baret, Jean-Christophe; Brosseau, Quentin; Semin, Benoit; Qu, Xiaopeng

    2012-02-01

    Emulsions are complex fluids already involved for a long time in a wide-range of industrial processes, such as, for example, food, cosmetics or materials synthesis [1]. More recently, applications of emulsions have been extended to new fields like biotechnology or biochemistry where the compartmentalization of compounds in emulsion droplets is used to parallelise (bio-) chemical reactions [2]. Interestingly, these applications pinpoint to fundamental questions dealing with surfactant dynamics, dynamic surface tension, hydrodynamic interactions and electrohydrodynamics. Droplet-based microfluidics is a very powerful tool to quantitatively study the dynamics of emulsions at the single droplet level or even at the single interface level: well-controlled emulsions are produced and manipulated using hydrodynamics, electrical forces, optical actuation and combination of these effects. We will describe here how droplet-based microfluidics is used to extract quantitative informations on the physical-chemistry of emulsions for a better understanding and control of the dynamics of these systems [3].[4pt] [1] J. Bibette et al. Rep. Prog. Phys., 62, 969-1033 (1999)[0pt] [2] A. Theberge et al., Angewandte Chemie Int. Ed. 49, 5846 (2010)[0pt] [3] J.-C. Baret et al., Langmuir, 25, 6088 (2009)

  3. Timescales of emulsion formation caused by anisotropic particles

    E-print Network

    Florian Günther; Stefan Frijters; Jens Harting

    2014-04-01

    Particle stabilized emulsions have received an enormous interest in the recent past, but our understanding of the dynamics of emulsion formation is still limited. For simple spherical particles, the time dependent growth of fluid domains is dominated by the formation of droplets, particle adsorption and coalescence of droplets (Ostwald ripening), which eventually can be almost fully blocked due to the presence of the particles. Ellipsoidal particles are known to be more efficient stabilizers of fluid interfaces than spherical particles and their anisotropic shape and the related additional rotational degrees of freedom have an impact on the dynamics of emulsion formation. In this paper, we investigate this point by means of simple model systems consisting of a single ellipsoidal particle or a particle ensemble at a flat interface as well as a particle ensemble at a spherical interface. By applying combined multicomponent lattice Boltzmann and molecular dynamics simulations we demonstrate that the anisotropic shape of ellipsoidal particles causes two additional timescales to be of relevance in the dynamics of emulsion formation: a relatively short timescale can be attributed to the adsorption of single particles and the involved rotation of particles towards the interface. As soon as the interface is jammed, however, capillary interactions between the particles cause a local reordering on very long timescales leading to a continuous change in the interface configuration and increase of interfacial area. This effect can be utilized to counteract the thermodynamic instability of particle stabilized emulsions and thus offers the possibility to produce emulsions with exceptional stability.

  4. Emulsion templated open porous membranes for protein purification.

    PubMed

    Pulko, Irena; Smrekar, Vida; Podgornik, Aleš; Krajnc, Peter

    2011-04-29

    Approximately 25 cm×25 cm large sheets of crosslinked highly porous poly(glycidyl methacrylate-co-ethyleneglycol dimethacrylate-co-ethylhexyl methacrylate) membranes with an average thicknesses between 285 and 565 ?m were prepared by casting a high internal phase emulsion (HIPE) containing monomers onto glass substrates and subsequent polymerisation. Open cellular porous polyHIPE type membranes were obtained with large pores (cavity) sizes between 3 and 10 ?m while interconnecting pores were between 1 and 3 ?m. The percentage of ethylhexyl acrylate and ethyleneglycol dimethacrylate influenced the flexibility and morphology of the resulting membranes. Porous membranes were chemically modified with diethylamine to yield functionalised supports for ion exchange chromatography. Cylindrical housings were used for positioning of the membranes and allowing flow of the mobile phase. Pulse experiments were used to study the flow characteristics and a homogeneous flow through the entire area of the membrane was found. Bovine serum albumin was purified by a 8 ml column containing functional membrane in modular shape; dynamic binding capacity was measured to be as high as 45 mg/ml. PMID:21168141

  5. Wide-gap Couette flows of dense emulsions: Local concentration measurements, and comparison between macroscopic and local constitutive law measurements through magnetic resonance imaging

    E-print Network

    Guillaume Ovarlez; Stéphane Rodts; Alexandre Ragouilliaux; Philippe Coussot; Julie Goyon; Annie Colin

    2008-10-20

    Flows of dense emulsions show many complex features among which long range nonlocal effects pose a problem for macroscopic characterization. In order to get around this problem, we study the flows of several dense emulsions in a wide-gap Couette geometry. We couple macroscopic rheometric experiments and local velocity measurements through MRI techniques. As concentration heterogeneities can be expected, we designed a method to measure the local droplet concentration in emulsions with a MRI device. In contrast to dense suspensions of rigid particles where very fast migration occurs under shear, we show that no migration takes place in dense emulsions even for strains as large as 100 000 in our systems. As a result of the absence of migration and of finite size effect, we are able to determine very precisely the local rheological behavior of several dense emulsions. As the materials are homogeneous, this behavior can also be inferred from purely macroscopic measurements. We thus suggest that properly analyzed purely macroscopic measurements in a wide-gap Couette geometry can be used as a tool to study the local constitutive laws of dense emulsions. All behaviors are basically consistent with Herschel-Bulkley laws of index 0.5, but discrepancies exist at the approach of the yield stress due to slow shear flows below the apparent yield stress in the case of a strongly adhesive emulsion. The existence of a constitutive law accounting for all flows contrasts with previous results obtained within a microchannel by Goyon et al. (2008): the use of a wide-gap Couette geometry is likely to prevent here from nonlocal finite size effects; it also contrasts with the observations of B\\'ecu et al. (2006).

  6. Are Water-in-Oil-Emulsions Suitable Model Systems for Cloud Glaciation?

    NASA Astrophysics Data System (ADS)

    Handle, Karl; Loerting, Thomas; Bogdan, Anatoli; Weiss, Fabian; Pummer, Bernhard; Grothe, Hinrich

    2013-04-01

    The technique of studying aqueous solutions emulsified in oil matrices is widely used in the scientific community as a model system for aqueous droplets in the atmosphere, e.g., in the context of ice nucleation and cloud glaciation. These studies are based on the assumption that the interaction between aqueous and oil phase is negligible. In this study we critically test the validity of this assumption by systematically varying the parameters of the emulsification procedure for the study of the freezing behaviour of dilute and concentrated solutions of organic acids, e.g., citric acid, and inorganic salts, e.g., ammonium sulphate. In particular we vary the type of oil, the type of surfactant, the water to oil ratio, the mixing time and the temperature, at which the emulsion is prepared. These emulsions are studied in the context of cloud glaciation by cooling to < 150 K and reheating to ambient temperature. We specifically check for the droplets sizes and distribution as well as imperfectly emulsified regions from optical microscopy observations, first and second freezing events, cold-crystallization upon heating, melting events and possible glass-transitions from differential scanning calorimetry experiments as well as for the phase mixtures and types of ice (cubic vs. hexagonal) formed by powder X-ray diffraction as a function of temperature. The results clearly show that not all emulsions behave alike in these experiments and that it is important to be aware about the possibility of the oil matrix interfering with the experiment, e.g., for oils that vitrify at atmospherically relevant temperatures.

  7. Superparamagnetic polymer emulsion particles from a soap-free seeded emulsion polymerization and their application for lipase immobilization.

    PubMed

    Cui, Yanjun; Chen, Xia; Li, Yanfeng; Liu, Xiao; Lei, Lin; Zhang, Yakui; Qian, Jiayu

    2014-01-01

    Using emulsion copolymer of styrene (St), glycidyl methacrylate (GMA) and 2-hydroxyethyl methacrylate (HEMA) as seed latexes, the superparamagnetic polymer emulsion particles were prepared by seeded emulsion copolymerization of butyl methacrylate (BMA), vinyl acetate (VAc) and ethylene glycol dimethacrylate in the presence of the seed latexes and superparamagnetic Fe3O4/SiOx nanoparticles (or Fe3O4-APTS nanoparticles) through a two-step process, without addition of any emulsifier. The magnetic emulsion particles named P(St-GMA-HEMA)/P(BMA-VAc) were characterized by transmission electron microscope and vibrating sample magnetometry. The results showed that the magnetic emulsion particles held a structure with a thinner shell (around 100 nm) and a bigger cavity (around 200 nm), and possessed a certain level of magnetic response. The resulting magnetic emulsion particles were employed in the immobilization of lipase by two strategies to immobilized lipase onto the resulting magnetic composites directly (S-1) or using glutaraldehyde as a coupling agent (S-2), thus, experimental data showed that the thermal stability and reusability of immobilized lipase based on S-2 were higher than that of S-1. PMID:24114322

  8. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63...limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators...producing styrene butadiene rubber using an emulsion process shall operate the process...

  9. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63...limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators...producing styrene butadiene rubber using an emulsion process shall operate the process...

  10. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63...limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators...producing styrene butadiene rubber using an emulsion process shall operate the process...

  11. 40 CFR 63.500 - Back-end process provisions-carbon disulfide limitations for styrene butadiene rubber by emulsion...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...limitations for styrene butadiene rubber by emulsion processes. 63.500 Section 63...limitations for styrene butadiene rubber by emulsion processes. (a) Owners or operators...producing styrene butadiene rubber using an emulsion process shall operate the process...

  12. Asphaltene and solids-stabilized water-in-oil emulsions

    NASA Astrophysics Data System (ADS)

    Sztukowski, Danuta M.

    Water-in-crude oil emulsions are a problem in crude oil production, transportation, and processing. Many of these emulsions are stabilized by asphaltenes and native oilfield solids adsorbed at the oil-water interface. Design of effective emulsion treatments is hampered because there is a lack of understanding of the role asphaltenes and solids play in stabilizing these emulsions. In this work, the structural, compositional and rheological properties of water/hydrocarbon interfaces were determined for model emulsions consisting of water, toluene, heptane, asphaltenes and native oilfield solids. The characteristics of the interface were related to the properties of asphaltenes and native solids. Emulsion stability was correlated to interfacial rheology. A combination of vapour pressure osmometry, interfacial tension and emulsion gravimetric studies indicated that asphaltenes initially adsorb at the interface as a monolayer of self-associated molecular aggregates. It was demonstrated why it is necessary to account for asphaltene self-association when interpreting interfacial measurements. The interfacial area of Athabasca asphaltenes was found to be approximately 1.5 nm2 and did not vary with concentration or asphaltene self-association. Hence, more self-associated asphaltenes simply formed a thicker monolayer. The interfacial monolayer observed in this work varied from 2 to 9 nm in thickness. The asphaltene monolayer was shown to adsorb reversibly only at short interface aging times. The film gradually reorganizes at the interface to form a rigid, irreversibly adsorbed network. The elastic and viscous moduli can be modeled using the Lucassen-van den Tempel (LVDT) model when the aging time is less than 10 minutes. An increase in film rigidity can be detected with an increase in the total elastic modulus. Increased film rigidity was shown to reduce the rate of coalescence in an emulsion and increase overall emulsion stability (reduce free water resolution). The rate of coalescence and the free water resolution of emulsions decreased when the interface aging time increased, the heptane fraction in heptol increased, and the asphaltene concentration decreased. For systems in which asphaltenes do not leave the interface during coalescence, the rate of coalescence correlated to the measured total modulus over a range of asphaltene concentrations, solvent qualities, and interface aging times. For systems in which asphaltenes leave the interface during coalescence, the correlation under-predicted the coalescence rate because the total modulus increases as material leaves the interface. (Abstract shortened by UMI.)

  13. Water-in-triglyceride oil emulsions. Effect of fat crystals on stability

    Microsoft Academic Search

    Dorota Johansson; Björn Bergenståhl; Eva Lundgren

    1995-01-01

    The influence of low concentrations (0.1-5%) of fat crystals on the stability of water-in-soybean oil emulsions was examined\\u000a by light scattering and sedimentation experiments. Both the initial flocculation\\/coalescence rate and long-term stability\\u000a against water separation were determined. The initial flocculation\\/coalescence rate increased upon addition of small amounts\\u000a of fat crystals. When the crystal concentration was increased above a critical concentration

  14. Linear and nonlinear rheology of dense emulsions across the glass and the jamming regimes.

    PubMed

    Scheffold, F; Cardinaux, F; Mason, T G

    2013-12-18

    We discuss the linear and nonlinear rheology of concentrated microscale emulsions, amorphous disordered solids composed of repulsive and deformable soft colloidal spheres. Based on recent results from simulation and theory, we derive quantitative predictions for the dependences of the elastic shear modulus and the yield stress on the droplet volume fraction. The remarkable agreement with experiments we observe supports the scenario that the repulsive glass and the jammed state can be clearly identified in the rheology of soft spheres at finite temperature while crossing continuously from a liquid to a highly compressed yet disordered solid. PMID:24222446

  15. Tunable WGM resonators from optically trapped dye doped liquid crystal emulsion droplets

    NASA Astrophysics Data System (ADS)

    Šerý, Mojmír.; Pilát, Zden?k.; Ježek, Jan; Aas, Mehdi; Kiraz, Alper; Zemánek, Pavel

    2014-09-01

    We have built a complex apparatus for optical trapping, stretching, heating and concurrent whispering gallery mode (WGM) lasing excitation of liquid crystal (LC) emulsion micro-droplets doped with various fluorescent dyes. We have explored the changes of WGM lasing wavelength when the LC droplets were optically stretched or electrically heated beyond the transition to the isotropic phase. We have found that the range of lasing wavelengths was in some cases considerably higher than when we optically stretched ordinary fluorescent oil droplets in our previous experiments.

  16. Observations of Primary Electrons with an Emulsion Chamber by Automatic Scanning Method

    NASA Astrophysics Data System (ADS)

    Sato, Y.; Ohmori, R.; Komori, Y.; Yoshida, K.; Tateyama, N.; Shirai, T.; Yuda, T.; Kobayashi, T.; Yamagami, T.; Saito, Y.; Nishimura, J.

    2003-07-01

    This experiment is designed to observe the accurate electron spectrum beyond 20GeV with an emulsion chamb er, which was exposed to cosmic rays at a balloon altitude. The balloon was launched from Sanriku Balloon Center (ISAS, Japan), in 2001. A new automatic scanning system is intro duced for scanning and analysis of the electron showers in the chamb er. The performance of this system was carefully studied by using calibration plates exposed to electron beams from the accelerator. Scanning and analysis for primary electrons beyond 20 GeV and the future prosp ect of obsevations using this method is reported.

  17. Study on target interactions in emulsion chamber - Brasil-Japan emulsion chamber collaboration

    NASA Astrophysics Data System (ADS)

    Ballester, M.; Santos, C.; Bellandi Filho, J.; Chinellato, J. A.; Dobrigkeit, C.; Lattes, C. M. G.; Marques, A.; Menon, M. J.; Navia, C. E.; Sawayanagi, K.

    Experimental results are presented from observations of 80 target nuclear interactions where the total gamma-ray energy is greater than or equal to 20 TeV. Evidence is presented for the existence of two types of interactions; the interpretation is given on the basis of a fire-ball model. Two-story emulsion chambers exposed at Mount Chacaltaya, in Bolivia (5,220 m above sea level), are used. Gamma rays from nuclear interactions in the target layer of petroleum pitch (1/3 of the nuclear mean free path in thickness) are detected through observations of the electron showers generated by them in the lower chamber

  18. Sunflower-seed oil body emulsions: Rheology and stability assessment of a natural emulsion

    Microsoft Academic Search

    D. A. White; I. D. Fisk; J. R. Mitchell; B. Wolf; S. E. Hill; D. A. Gray

    2008-01-01

    The viscoelastic characteristics of a purified oil body cream (67.6±0.7% lipid, 5.4±0.7% protein and 25.2±0.1% moisture) recovered from sunflower seeds (Helianthus annuus L.) have been determined. Moreover, the effects of pH (2–7) and CaCl2 concentration (0–150mM) on rheology and physical stability of oil body emulsions have been studied. Oscillatory measurements showed that the purified oil body cream exhibited weak gel-like

  19. Development of novel zein-sodium caseinate nanoparticle (ZP)-stabilized emulsion films for improved water barrier properties via emulsion/solvent evaporation.

    PubMed

    Wang, Li-Juan; Yin, Ye-Chong; Yin, Shou-Wei; Yang, Xiao-Quan; Shi, Wei-Jian; Tang, Chuan-He; Wang, Jin-Mei

    2013-11-20

    This work attempted to develop novel high barrier zein/SC nanoparticle (ZP)-stabilized emulsion films through microfluidic emulsification (ZPE films) or in combination with solvent (ethyl acetate) evaporation techniques (ZPE-EA films). Some physical properties, including tensile and optical properties, water vapor permeability (WVP), and surface hydrophobicity, as well as the microstructure of ZP-stabilized emulsion films were evaluated and compared with SC emulsion (SCE) films. The emulsion/solvent evaporation approach reduced lipid droplets of ZP-stabilized emulsions, and lipid droplets of ZP-stabilized emulsions were similar to or slightly lower than that of SC emulsions. However, ZP- and SC-stabilized emulsion films exhibited a completely different microstructure, nanoscalar lipid droplets were homogeneously distributed in the ZPE film matrix and interpenetrating protein-oil complex networks occurred within ZPE-EA films, whereas SCE films presented a heterogeneous microstructure. The different stabilization mechanisms against creaming or coalescence during film formation accounted for the preceding discrepancy of the microstructures between ZP-and SC-stabilized emulsion films. Interestingly, ZP-stabilized emulsion films exhibited a better water barrier efficiency, and the WVP values were only 40-50% of SCE films. A schematic representation for the formation of ZP-stabilized emulsion films was proposed to relate the physical performance of the films with their microstructure and to elucidate the possible forming mechanism of the films. PMID:24175664

  20. The vaporizing behavior of the fuel droplet of water-in-oil emulsions on the hot surface

    Microsoft Academic Search

    Kyoji Kimoto; Yukio Owashi; Yoshihiro Omae

    1986-01-01

    Experiments were carried out to investigate qualitatively the effects of the emulsion internal phase structure, such as the size distribution of water droplets, on the microexplosion phenomena of water-in-'A'-heavy-oil emulsified droplets vaporizing on a hot surface. The results confirm that the size distribution of water droplets in the emulsified fuels plays a very important role in the boilng phenomena, in

  1. Flow and cold heat-storage characteristics of phase-change emulsion in a coiled double-tube heat exchanger

    Microsoft Academic Search

    H. Inaba; S. Morita

    1995-01-01

    This paper dealt with the flow and cold heat-storage characteristics of the oil (tetradecane, CââHââ, freezing point 278.9 K)\\/water emulsion as a latent heat-storage material having a low melting point. A coiled double-tube heat exchanger was used for the cold heat storage experiment. The pressure drop, the heat transfer coefficient, and the finishing time of cold heat storage in the

  2. Breaking oil-in-water emulsions stabilized by yeast.

    PubMed

    Furtado, Guilherme F; Picone, Carolina S F; Cuellar, Maria C; Cunha, Rosiane L

    2015-04-01

    Several biotechnological processes can show an undesirable formation of emulsions making difficult phase separation and product recovery. The breakup of oil-in-water emulsions stabilized by yeast was studied using different physical and chemical methods. These emulsions were composed by deionized water, hexadecane and commercial yeast (Saccharomyces cerevisiae). The stability of the emulsions was evaluated varying the yeast concentration from 7.47 to 22.11% (w/w) and the phases obtained after gravity separation were evaluated on chemical composition, droplet size distribution, rheological behavior and optical microscopy. The cream phase showed kinetic stability attributed to mechanisms as electrostatic repulsion between the droplets, a possible Pickering-type stabilization and the viscoelastic properties of the concentrated emulsion. Oil recovery from cream phase was performed using gravity separation, centrifugation, heating and addition of demulsifier agents (alcohols and magnetic nanoparticles). Long centrifugation time and high centrifugal forces (2h/150,000×g) were necessary to obtain a complete oil recovery. The heat treatment (60°C) was not enough to promote a satisfactory oil separation. Addition of alcohols followed by centrifugation enhanced oil recovery: butanol addition allowed almost complete phase separation of the emulsion while ethanol addition resulted in 84% of oil recovery. Implementation of this method, however, would require additional steps for solvent separation. Addition of charged magnetic nanoparticles was effective by interacting electrostatically with the interface, resulting in emulsion destabilization under a magnetic field. This method reached almost 96% of oil recovery and it was potentially advantageous since no additional steps might be necessary for further purifying the recovered oil. PMID:25791419

  3. Design and development of oral nanoparticulated insulin in multiple emulsion.

    PubMed

    Siddhartha, T Venkata; Senthil, V; Kishan, Ilindra Sai; Khatwal, Rizwan Basha; Madhunapantula, SubbaRao V

    2014-01-01

    The present research aimed at developing an injection-free nanoparticulated formulation in multiple emulsion form, for oral delivery of insulin, which otherwise undergoes degradation in the gastric environment if administered orally. Insulin-polymeric nanoparticles were prepared using layer by layer (LbL) adsorption method and incorporated into an emulsion to form a nanoparticulated multiple emulsion. Using 0.6 M sodium chloride, the insulin nanoaggregates of 300-400 nm size were obtained about a yield of 94%. The characteristics of a representative nanoparticle were as follows: particle size - 391.9±0.41 nm, polydispersity index -0.425, zeta potential- +20.6 mv, encapsulation efficiency- 86.7±1.42% and percentage entrapment efficiency of the insulin-polymeric nanoparticles in the inner aqueous phase of emulsion was 84.6%. The FT-IR analysis confirms that there were no drug interactions with the polymers. Stability analysis carried out for 3 months at 8-40 °C, showed only minor changes at the end period. The release kinetics of the nanoparticulated multiple emulsion at pH 7.4 followed first order kinetics and obeyed the Fickian law. However, at pH 2.0 the release kinetics from nanoparticulated multiple emulsion followed zero order kinetics without obeying to the Fickian law. In conclusion, our data demonstrate that the nanoparticulated multiple emulsion formulation has good release characteristics and imparted a tolerable protection for insulin at different pH conditions, which may be exploited for oral administration. PMID:24730439

  4. Dynamically reconfigurable complex emulsions via tunable interfacial tensions.

    PubMed

    Zarzar, Lauren D; Sresht, Vishnu; Sletten, Ellen M; Kalow, Julia A; Blankschtein, Daniel; Swager, Timothy M

    2015-02-26

    Emulsification is a powerful, well-known technique for mixing and dispersing immiscible components within a continuous liquid phase. Consequently, emulsions are central components of medicine, food and performance materials. Complex emulsions, including Janus droplets (that is, droplets with faces of differing chemistries) and multiple emulsions, are of increasing importance in pharmaceuticals and medical diagnostics, in the fabrication of microparticles and capsules for food, in chemical separations, in cosmetics, and in dynamic optics. Because complex emulsion properties and functions are related to the droplet geometry and composition, the development of rapid, simple fabrication approaches allowing precise control over the droplets' physical and chemical characteristics is critical. Significant advances in the fabrication of complex emulsions have been made using a number of procedures, ranging from large-scale, less precise techniques that give compositional heterogeneity using high-shear mixers and membranes, to small-volume but more precise microfluidic methods. However, such approaches have yet to create droplet morphologies that can be controllably altered after emulsification. Reconfigurable complex liquids potentially have great utility as dynamically tunable materials. Here we describe an approach to the one-step fabrication of three- and four-phase complex emulsions with highly controllable and reconfigurable morphologies. The fabrication makes use of the temperature-sensitive miscibility of hydrocarbon, silicone and fluorocarbon liquids, and is applied to both the microfluidic and the scalable batch production of complex droplets. We demonstrate that droplet geometries can be alternated between encapsulated and Janus configurations by varying the interfacial tensions using hydrocarbon and fluorinated surfactants including stimuli-responsive and cleavable surfactants. This yields a generalizable strategy for the fabrication of multiphase emulsions with controllably reconfigurable morphologies and the potential to create a wide range of responsive materials. PMID:25719669

  5. Dynamically reconfigurable complex emulsions via tunable interfacial tensions

    NASA Astrophysics Data System (ADS)

    Zarzar, Lauren D.; Sresht, Vishnu; Sletten, Ellen M.; Kalow, Julia A.; Blankschtein, Daniel; Swager, Timothy M.

    2015-02-01

    Emulsification is a powerful, well-known technique for mixing and dispersing immiscible components within a continuous liquid phase. Consequently, emulsions are central components of medicine, food and performance materials. Complex emulsions, including Janus droplets (that is, droplets with faces of differing chemistries) and multiple emulsions, are of increasing importance in pharmaceuticals and medical diagnostics, in the fabrication of microparticles and capsules for food, in chemical separations, in cosmetics, and in dynamic optics. Because complex emulsion properties and functions are related to the droplet geometry and composition, the development of rapid, simple fabrication approaches allowing precise control over the droplets' physical and chemical characteristics is critical. Significant advances in the fabrication of complex emulsions have been made using a number of procedures, ranging from large-scale, less precise techniques that give compositional heterogeneity using high-shear mixers and membranes, to small-volume but more precise microfluidic methods. However, such approaches have yet to create droplet morphologies that can be controllably altered after emulsification. Reconfigurable complex liquids potentially have great utility as dynamically tunable materials. Here we describe an approach to the one-step fabrication of three- and four-phase complex emulsions with highly controllable and reconfigurable morphologies. The fabrication makes use of the temperature-sensitive miscibility of hydrocarbon, silicone and fluorocarbon liquids, and is applied to both the microfluidic and the scalable batch production of complex droplets. We demonstrate that droplet geometries can be alternated between encapsulated and Janus configurations by varying the interfacial tensions using hydrocarbon and fluorinated surfactants including stimuli-responsive and cleavable surfactants. This yields a generalizable strategy for the fabrication of multiphase emulsions with controllably reconfigurable morphologies and the potential to create a wide range of responsive materials.

  6. Phytosterol colloidal particles as Pickering stabilizers for emulsions.

    PubMed

    Liu, Fu; Tang, Chuan-He

    2014-06-01

    Water-insoluble phytosterols were developed into a kind of colloidal particle as Pickering stabilizers for emulsions by a classic anti-solvent method using 100% ethanol as the organic phase to solubilize the phytosterols and whey protein concentrate (WPC) as the emulsifier. The colloidal particles in the dispersion, with morphology of stacked platelet-like sheets, had a mean diameter of 44.7 and 24.7 ?m for the volume- and surface-averaged sizes, respectively. The properties and stability of the emulsions stabilized by these colloidal particles were highly dependent upon the applied total solid concentration (c; in the dispersion) and oil fraction (ø). The results indicated that (1) at a low c value (<1.0%, w/v) the emulsions were susceptible to phase separation, even at a low ø of 0.2, (2) at low ø values (e.g., 0.2 or 0.3) and a relatively high c value (1.0%, w/v, or above), a severe droplet flocculation occurred for the emulsions, and (3) when both c and ø were appropriately high, a kind of self-supporting gel-like emulsions could be formed. More interestingly, a phase inversion of the emulsions from the oil-in-water to water-in-oil type was observed, upon the ø increasing from 0.2 to 0.6 (especially at high c values, e.g., 3.0%, w/v). The elaborated Pickering emulsions stabilized by the phytosterol colloidal particles with a gel-like behavior would provide a candidate to act as a novel delivery system for active ingredients. PMID:24848560

  7. Topological Defects and Interactions in Nematic Emulsions

    E-print Network

    T. C. Lubensky; David Pettey; Nathan Currier; Holger Stark

    1997-07-12

    Inverse nematic emulsions in which surfactant-coated water droplets are dispersed in a nematic host fluid have distinctive properties that set them apart from dispersions of two isotropic fluids or of nematic droplets in an isotropic fluid. We present a comprehensive theoretical study of the distortions produced in the nematic host by the dispersed droplets and of solvent mediated dipolar interactions between droplets that lead to their experimentally observed chaining. A single droplet in a nematic host acts like a macroscopic hedgehog defect. Global boundary conditions force the nucleation of compensating topological defects in the nematic host. Using variational techniques, we show that in the lowest energy configuration, a single water droplet draws a single hedgehog out of the nematic host to form a tightly bound dipole. Configurations in which the water droplet is encircled by a disclination ring have higher energy. The droplet-dipole induces distortions in the nematic host that lead to an effective dipole-dipole interaction between droplets and hence to chaining.

  8. Phagocytosis of immunoglobulin-coated emulsion droplets.

    PubMed

    Ben M'Barek, Kalthoum; Molino, Diana; Quignard, Sandrine; Plamont, Marie-Aude; Chen, Yong; Chavrier, Philippe; Fattaccioli, Jacques

    2015-05-01

    Phagocytosis by macrophages represents a fundamental process essential for both immunity and tissue homeostasis. The size of targets to be eliminated ranges from small particles as bacteria to large objects as cancerous or senescent cells. Most of our current quantitative knowledge on phagocytosis is based on the use of solid polymer microparticles as model targets that are well adapted to the study of phagocytosis mechanisms that do not involve any lateral mobility of the ligands, despite the relevance of this parameter in the immunological context. Herein we designed monodisperse, IgG-coated emulsion droplets that are efficiently and specifically internalized by macrophages through in-vitro Fc?R-mediated phagocytosis. We show that, contrary to solid polymeric beads, droplet uptake is efficient even for low IgG densities, and is accompagnied by the clustering of the opsonins in the zone of contact with the macrophage during the adhesion step. Beyond the sole interest in the design of the material, our results suggest that lateral mobility of proteins at the interface of a target greatly enhances the phagocytic uptake. PMID:25771017

  9. Wetting gradient induced separation of emulsions: A combined experimental and lattice Boltzmann computer simulation study

    E-print Network

    Fathollah Varnik; Pagra Truman; Bin Wu; Petra Uhlmann; Dierk Raabe; Manfred Stamm

    2009-10-16

    Guided motion of emulsions is studied via combined experimental and theoretical investigations. The focus of the work is on basic issues related to driving forces generated via a step-wise (abrupt) change in wetting properties of the substrate along a given spatial direction. Experiments on binary emulsions unambiguously show that selective wettability of the one of the fluid components (water in our experiments) with respect to the two different parts of the substrate is sufficient in order to drive the separation process. These studies are accompanied by approximate analytic arguments as well as lattice Boltzmann computer simulations, focusing on effects of a wetting gradient on internal droplet dynamics as well as its relative strength compared to volumetric forces driving the fluid flow. These theoretical investigations show qualitatively different dependence of wetting gradient induced forces on contact angle and liquid volume in the case of an open substrate as opposed to a planar channel. In particular, for the parameter range of our experiments, slit geometry is found to give rise to considerably higher separation forces as compared to open substrate.

  10. Phase Behavior and Emulsion Stability of the Aot/Decane/ Water/NaCl System at Very Low Volume Fractions of Oil

    E-print Network

    Yithanllili Bastidas; Lisset Hernaandez; Issarly Rivas; Kareem Rahn-Chique; German Urbina-Villalba

    2014-10-09

    The stability of a ternary system composed of decane/water/Aerosol-OT and salt is revisited. Phase diagrams and emulsions similar in composition to those previously studied by Hofman and Stein [Hofman, 1991] were made. Ac- cording to our results, and contrary to the common experience, these systems exhibit a maximum of stability very close to the balance zone.

  11. Thermodynamically Stable Pickering Emulsions Stabilized by Janus Dumbbells

    NASA Astrophysics Data System (ADS)

    Tu, Fuquan; Park, Bum Jun; Lee, Daeyeon

    2013-03-01

    Janus particles have two sides with different, often opposite, surface properties. Janus dumbbell is one type of Janus particles that consists of two partially fused spherical lobes. It is possible to independently control the geometry and surface wettability of Janus dumbbells. Janus dumbbells can also be produced in a large quantity, making them useful for practical applications such as emulsion stabilization. In this work, we calculate the free energy of emulsion formation using amphiphilic Janus dumbbells as solid surfactants. In contrast to kinetically stable emulsions stabilized by homogeneous particles, emulsion stabilized by Janus dumbbells can be thermodynamically stable. There also exists an optimal radius of droplets that can be stabilized by infinite or limited number of amphiphilic dumbbells in the continuous phase. We demonstrate that the optimal radius of dumbbell-stabilized droplets can be predicted based on the volume of the dispersed phase and the volume fraction of dumbbells in the continuous phase. We believe our calculation will provide guidelines for using Janus dumbbells as colloid surfactants to generate stable emulsions.

  12. Delivery of Chlorambucil Using an Acoustically-Triggered, Perfluoropentane Emulsion

    PubMed Central

    Fabiilli, Mario L.; Haworth, Kevin J.; Sebastian, Ian E.; Kripfgans, Oliver D.; Carson, Paul L.; Fowlkes, J. Brian

    2010-01-01

    Ultrasound-mediated delivery systems have mainly focused on microbubble contrast agents as carriers of drugs or genetic material. This study utilizes micron-sized, perfluoropentane (PFP) emulsions as carriers for chlorambucil (CHL), a lipophilic chemotherapeutic. The release of CHL is achieved via acoustic droplet vaporization (ADV), whereby the superheated emulsion is converted into gas bubbles using ultrasound. Emulsions were made using an albumin shell and soybean oil as the CHL carrier. The ratio of the PFP to soybean oil phases in the droplets, as well as the fraction of droplets that vaporize per ultrasound exposure were shown to correlate with droplet diameter. A 60-minute incubation with the CHL-loaded emulsion caused a 46.7% cellular growth inhibition, whereas incubation with the CHL-loaded emulsion that was exposed to ultrasound at 6.3 MHz caused an 84.3% growth inhibition. This difference was statistically significant (p < 0.01), signifying that ADV can be used as a method to substantially enhance drug delivery. PMID:20691925

  13. Preparation of double Pickering emulsions stabilized by chemically tailored nanocelluloses.

    PubMed

    Cunha, Ana G; Mougel, Jean-Bruno; Cathala, Bernard; Berglund, Lars A; Capron, Isabelle

    2014-08-12

    Nanocelluloses are bio-based nanoparticles of interest as stabilizers for oil-in-water (o/w) Pickering emulsions. In this work, the surface chemistry of nanocelluloses of different length, nanofibrillated cellulose (NFC, long) and cellulose nanocrystals (CNC, short), was successfully tailored by chemical modification with lauroyl chloride (C12). The resulting nanofibers were less hydrophilic than the original and able to stabilize water-in-oil (w/o) emulsions. The combination of the two types of nanocelluloses (C12-modified and native) led to new surfactant-free oil-in-water-in-oil (o/w/o) double emulsions stabilized by nanocellulose at both interfaces. Characterization was performed with respect to droplet size distribution, droplet stability over time, and stability after centrifugation. Nanocellulose-based Pickering emulsions can be designed with a substantial degree of control, as demonstrated by the stability of the chemically tailored NFC double emulsions. Furthermore, it was demonstrated that increased nanofiber length leads to increased stability. PMID:25046221

  14. Investigation of different emulsion systems for dermal delivery of nicotinamide.

    PubMed

    Tuncay, Sakine; Özer, Özgen

    2013-01-01

    Nicotinamide (NA) has been shown to have beneficial effects on several skin diseases such as tumor, acne vulgaris, photodamage, cellulite and atopic dermatitis. The purpose of this study was to develop a multiple emulsion and a microemulsion formulation as delivery systems for NA. A two-step process was used to prepare the W/O/W multiple emulsion. Optimum microemulsion formulation was selected by using construction of pseudo-ternary phase diagram. The physicochemical properties such as droplet size and viscosity measurements, stability studies were also evaluated. Ex-vivo permeation studies were performed with Franz-type diffusion cells and the samples were analysed by high performance liquid chromatography (HPLC). The permeation data showed that there was no significant difference between multiple emulsion and microemulsion (p > 0.05). Transepidermal water loss (TEWL) was also measured. As a result of TEWL studies, a slight increase of TEWL values was observed for microemulsion formulation on rat skin when compared with multiple emulsion and commercial formulation. The results suggested that microemulsion and multiple emulsion formulations could be new and alternative dosage forms for topical application of NA. PMID:23742727

  15. Stability determination of crude oil emulsions by electrorheological measurement

    NASA Astrophysics Data System (ADS)

    Alvarado, Vladimir; Wang, Xiuyu; Plancher, Henry

    2008-11-01

    Emulsion stability is paramount to the success of many industrial applications and the remediation of naturally undesirable occurring fluid-fluid dispersions. Bottle tests and critical electric field (Ec) measurements are two commonly used techniques to interpret emulsion stability. In the former, the amount of water resolved after gravitational settling test or centrifugation as a function of time is used as an indicator of stability. Generally, the lower the total water fraction resolved, the higher the emulsion stability. In the second method, the value of Ec leading to drop coalescence is used as an indicator of stability. A larger value of Ec is a reflection of a more stable dispersion. The value of Ec is usually determined by measuring a sudden increase in electrical conductivity in water-crude oil emulsions as the field value is increased. In this work, an electrorheological test is used to establish the value of Ec and hence the stability criterion. Results of electrorheological measurements are compared to results of bottle tests for water-crude oil emulsions with or without stabilizing solid micro-particles. Results will show the consistency among the different measuring techniques, for a wide range of ionic strength and composition of the water phase and two crude oils.

  16. Spontaneous spreading of particle monolayers from unstable Pickering emulsions

    NASA Astrophysics Data System (ADS)

    Cheng, Hsin-Ling; Velankar, Sachin

    2009-03-01

    Partially-wettable particles can adsorb at liquid/liquid interfaces and give stable Pickering emulsions. However, if there are insufficient particles, then the emulsion is unstable. In such an unstable emulsion, we document a remarkable phenomenon, viz. coalescence of an oil/water/particle Pickering emulsion contained in a vial induces a particle film to climb up the walls of the vial. While this has been noted previously with nanoparticles, we show that such film-climbing is highly general and can be induced by a variety of particle types, particle sizes ranging from a few nm to a few microns, and different emulsion types. Many of the features of film growth described previously with nm-sized particles are found to remain true even with the far larger particles studied here. Binks et al., Langmuir, 22, 4100, 2006, have postulated that the particle films that climb up the walls of a vial are actually comprised of one oil layer and one water layer, with particles adsorbed at the interface between them. We confirmed this ``sandwich'' structure experimentally and also show that such interfacially-adsorbed particles can easily exert the very modest surface pressure necessary to sustain the weight of the film. Finally, while some climbing films are tightly-packed particle monolayers, tight packing is not essential; even sparsely-populated monolayers can display film climbing.

  17. Ca2+ ion responsive pickering emulsions stabilized by PSSMA nanoaggregates.

    PubMed

    Zhao, Chunhua; Tan, Junjun; Li, Wei; Tong, Kun; Xu, Jian; Sun, Dejun

    2013-11-26

    A novel Ca(2+) ion responsive particulate emulsifier, which is based on copolymer nanoaggregates, is reported in this work. Results from dynamic light scattering (DLS) and cryo-transmission electron microscopy (cryo-TEM) indicate that the formation of poly (4-styrenesulfonic acid-co-maleic acid) sodium salt (PSSMA) nanoaggregates is strongly dependent on Ca(2+) concentration. The PSSMA copolymer only aggregates above a critical Ca(2+) concentration (0.2 M) with an average diameter of 10-40 nm. After dilution with water, PSSMA nanoaggregates are rapidly redissolved again. On the basis of the properties of PSSMA nanoaggregates, Ca(2+) ion responsive Pickering emulsions were successfully prepared. At high Ca(2+) concentrations, the emulsions with high stability against coalescence can be prepared with the size in the submicrometer range as determined by DLS. Cryo-TEM and dynamic interfacial tension results confirm the adsorption of PSSMA nanoaggregates at the interface, which is the key to the stability of the emulsions. More importantly, rapid demulsification can be achieved by dilution with water on demand. It is because, upon dilution with water, PSSMA nanoaggregates undergo a transition from stable nanoaggregates to individual polymer chains, which leads to interfacial desorption of nanoaggregates and rapid demulsification of emulsions. Thus, this finding presents a new manipulation on emulsion stability and is expected to provide a useful guidance in the fields of oil recovery, food science, environment protection, and so on. PMID:24188032

  18. Treatment methods for breaking certain oil and water emulsions

    DOEpatents

    Sealock, Jr., L. John (W. Richland, WA); Baker, Eddie G. (Richland, WA); Elliott, Douglas C. (Richland, WA)

    1992-01-01

    Disclosed are treatment methods for breaking emulsions of petroleum oil and salt water, fatty oil and water, and those resulting from liquefication of organic material. The emulsions are broken by heating to a predetermined temperature at or above about 200.degree. C. and pressurizing to a predetermined pressure above the vapor pressure of water at the predetermined temperature to produce a heated and pressurized fluid. The heated and pressurized fluid is contained in a single vessel at the predetermined temperature and pressure for a predetermined period of time to effectively separate the emulsion into substantially distinct first and second phases, the first phase comprising primarily the petroleum oil, the second phase comprising primarily the water. The first and second phases are separately withdrawn from the vessel at a withdraw temperature between about 200.degree. C. and 374.degree. C. and a withdraw pressure above the vapor pressure of water at the withdraw temperature. Where solids are present in the certain emulsions, the above described treatment may also effectively separate the certain emulsion into a substantially distinct third phase comprising primarily the solids.

  19. Rejuvenation of Spent Media via Supported Emulsion Liquid Membranes

    NASA Technical Reports Server (NTRS)

    Wiencek, John M.

    2002-01-01

    The overall goal of this project is to maximize the reuseability of spent fermentation media. Supported emulsion liquid membrane separation, a highly efficient extraction technique, is used to remove inhibitory byproducts during fermentation; thus, improving the yield while reducing the need for fresh water. The key objectives of this study are: Develop an emulsion liquid membrane system targeting low molecular weight organic acids which has minimal toxicity on a variety of microbial systems; Conduct mass transfer studies to allow proper modeling and design of a supported emulsion liquid membrane system; Investigate the effect of gravity on emulsion coalescence within the membrane unit; Access the effect of water re-use on fermentation yields in a model microbial system; Develop a perfusion-type fermentor utilizing a supported emulsion liquid membrane system to control inhibitory fermentation byproducts; Work for the coming year will focus on the determination of toxicity of various solvents, selection of the emulsifying agents, as well as characterizing the mass transfer of hollow-fiber contactors.

  20. pH-Responsive Water-in-Water Pickering Emulsions.

    PubMed

    Nguyen, Bach T; Wang, Wenkai; Saunders, Brian R; Benyahia, Lazhar; Nicolai, Taco

    2015-03-31

    The structure and stability of water-in-water emulsions was investigated in the presence of spherical, pH-sensitive microgels. The emulsions were formed by mixing aqueous solutions of dextran and PEO. The microgels consisted of cross-linked, synthetic polymers with a radius that steeply increased from 60 to 220 nm with increasing pH within a narrow range around 7.0. At all pH values between 5.0 and 7.5, the microgels were preferentially situated at the interface, but only in a narrow range between pH 7.0 and 7.5, the emulsions were stable for at least 1 week. The droplet size was visualized with confocal laser scanning microscopy and was found to be smallest in the stable pH range. Emulsions could be stabilized or destabilized by small changes of the pH. Addition of small amounts of salt led to a shift of the pH range where the emulsions were stable. The effects of varying the microgel concentration and the polymer composition were investigated. PMID:25743065

  1. A Study on the Influence of Emulsion Droplet Size on the Skin Penetration of Tetracaine

    Microsoft Academic Search

    P. Izquierdo; J. W. Wiechers; E. Escribano; M. J. García-Celma; T. F. Tadros; J. Esquena; J. C. Dederen; C. Solans

    2007-01-01

    Objectives\\/Aims: The influence of emulsion droplet size on the skin penetration of a model drug, tetracaine, was studied. For this purpose, in vitro dermal and transdermal delivery of tetracaine from 6 emulsions (3 macro-emulsions with droplet sizes >1 ?m and 3 nano-emulsions with droplet sizes <100 nm) were tested. Methods: Two approaches were used: in the first one, the composition

  2. Phase and emulsion morphology diagrams of nonionic- amphiphile/oil/water systems and their interrelationships

    SciTech Connect

    Smith, D.H. [USDOE Morgantown Energy Technology Center, WV (United States); Kyunghee Lim [West Virginia Univ., Morgantown, WV (United States). Dept. of Chemical Engineering

    1992-09-01

    For two-phase, non-multiple emulsions, the emulsion morphology diagram shows, as a function of temperature and phase or component concentration, which phase is dispersed and which is the continuous one, as well as the temperatures and compositions at which inversions occur. The emulsion morphology diagram plays for emulsions a role that is similar to the role played by phase diagrams for phases.

  3. Phase and emulsion morphology diagrams of nonionic- amphiphile/oil/water systems and their interrelationships

    SciTech Connect

    Smith, D.H. (USDOE Morgantown Energy Technology Center, WV (United States)); Kyunghee Lim (West Virginia Univ., Morgantown, WV (United States). Dept. of Chemical Engineering)

    1992-01-01

    For two-phase, non-multiple emulsions, the emulsion morphology diagram shows, as a function of temperature and phase or component concentration, which phase is dispersed and which is the continuous one, as well as the temperatures and compositions at which inversions occur. The emulsion morphology diagram plays for emulsions a role that is similar to the role played by phase diagrams for phases.

  4. Microfluidic emulsion separation---simultaneous separation and sensing by multilayer nanofilm structures

    Microsoft Academic Search

    P. Uhlmann; F. Varnik; P. Truman; G. Zikos; J.-F. Moulin; P. Müller-Buschbaum; M. Stamm

    2011-01-01

    Emulsion separation is of high relevance for filtration applications, liquid-liquid-partitioning of biomolecules like proteins and recovery of products from droplet microreactors. Selective interaction of various components of an emulsion with substrates is used to design microfluidic flow chambers for efficient separation of emulsions into their individual components. Our lab-on-a-chip device consists of an emulsion separation cell with an integrated silicon

  5. The complexity of prescribing intravenous lipid emulsions.

    PubMed

    Waitzberg, Dan Linetzky; Torrinhas, Raquel Susana

    2015-01-01

    Intravenous lipid emulsions (LEs) are relevant for patients receiving parenteral nutrition because they prevent the depletion of essential fatty acids (FAs) and, as a highly dense energy source, enable the reduction of glucose provision, thereby decreasing the risks of hyperglycemia and hepatic impairment. The prescription of LEs is complex, due mainly to their distinct FA components, which may alter the immune response in different ways and distinctly influence inflammation, oxidative stress and blood coagulation according to their biochemical properties. In addition, an excess of other LE components, such as phospholipids and phytosterols, may be associated with hepatic steatosis and dysfunction. These associations do not represent direct risks or obstacles to LE use in metabolically stable patients but can render the choice of the best LE for hypermetabolic patients difficult. The infusion of LEs according to the available guidelines provides more benefit than harm and should be part of exclusive parenteral nutrition regimens or complement enteral nutrition when appropriate. The patient's metabolic profile should guide the type of FA and amount of lipids that are provided. For critically ill hypermetabolic patients, growing evidence indicates that standard LEs based solely on soybean oil should be avoided in favor of new LEs containing medium-chain triglycerides, olive oil, or fish oil to decrease the provision of potentially oxidative, inflammatory/immunosuppressive, and prothrombotic n-6 FAs. In addition, as sources of eicosapentaenoic and docosahexaenoic acids, LEs containing fish oil may be important for critically ill patients because they allow better modulation of the immune response and likely reduce the length of intensive care unity stay. However, current evidence precludes the recommendation of a specific LE for clinical use in this patient population. PMID:25471811

  6. Activation of Neuronal N-Methyl-d-Aspartate Receptor Channels by Lipid Emulsions

    Microsoft Academic Search

    Henry U. Weigt; Michael Georgieff; Cordian Beyer

    2002-01-01

    Lipid emulsions are widely used as carriers for hypnot- ics such as propofol, etomidate, and diazepam. It is as- sumed that the emulsions alone exert no effect on cellu- lar functions nor influence the pharmacokinetics, pharmacodynamics, or anesthetic and analgetic po- tency of the hypnotics they carry. To elucidate possible interactions between lipid emulsions and cell mem- branes, in particular

  7. One-step formation of multiple emulsions in microfluidics Adam R. Abate,a

    E-print Network

    One-step formation of multiple emulsions in microfluidics Adam R. Abate,a Julian Thieleab and David a robust way to create multiple emulsions with controllable shell thicknesses that can vary over a wide instability, we break the jet into multiple emulsions. By controlling the thickness of each layer of the jet

  8. Squeezing particle-stabilized emulsions into biliquid foams equation of state

    E-print Network

    Schofield, Andrew

    Squeezing particle-stabilized emulsions into biliquid foams ­ equation of state Louison Maurice a centrifuge, we measure the (pressure vs. density) equation of state of Pickering emulsions stabilized by hard developed a transparent Pickering emulsion, allowing us to determine local volume fraction as a function

  9. In vitro compartmentalization by double emulsions: sorting and gene enrichment by fluorescence activated cell sorting

    E-print Network

    Tawfik, Dan S.

    In vitro compartmentalization by double emulsions: sorting and gene enrichment by fluorescence September 2003 Abstract Water-in-oil (w/o) emulsions can be used to compartmentalize and select large gene libraries for a predetermined function. The aqueous droplets of the w/o emulsion function as cell

  10. A LOW-ENERGY EMULSIFICATION BATCH MIXER FOR CONCENTRATED OIL-IN-WATER EMULSIONS

    E-print Network

    Paris-Sud XI, Université de

    A LOW-ENERGY EMULSIFICATION BATCH MIXER FOR CONCENTRATED OIL-IN-WATER EMULSIONS Sylvain CAUBETa Ratio (HIPR) Oil-in-Water (O/W) emulsion using a new type of a two-rod batch mixer. The mixture allow a precise control of the concentrated emulsion droplet size distribution, which governs

  11. Spontaneously Formed trans-Anethol/Water/Alcohol Emulsions: Mechanism of Formation and Stability

    E-print Network

    Sprik, Rudolf

    Articles Spontaneously Formed trans-Anethol/Water/Alcohol Emulsions: Mechanism of Formation has a saturation limit at a droplet radius of about 1.5 µm. Thus, formed emulsions remain stable for months. 1. Introduction Spontaneously formed emulsions are created by simply bringing two immiscible

  12. High throughput production of single core double emulsions in a parallelized microfluidic device

    E-print Network

    High throughput production of single core double emulsions in a parallelized microfluidic device October 2011, Accepted 19th December 2011 DOI: 10.1039/c2lc21033a Double emulsions are useful templates for microcapsules and complex particles, but no method yet exists for making double emulsions with both high

  13. Pervaporation of Emulsion Droplets for the Templated Assembly of Spherical Particles: A Population Balance Model

    E-print Network

    Braatz, Richard D.

    Pervaporation of Emulsion Droplets for the Templated Assembly of Spherical Particles: A Population in Wiley Online Library (wileyonlinelibrary.com) The emulsion droplet solvent evaporation method is used is presented to describe this transport of solvent from nanocrystal- or polymer- laden droplets in an emulsion

  14. Experimental measurements of stress redistribution in flowing emulsions Kenneth W. Desmond and Eric R. Weeks

    E-print Network

    Weeks, Eric R.

    Experimental measurements of stress redistribution in flowing emulsions Kenneth W. Desmond and Eric emulsions at area fractions 0.88. Using microscopy, we measure droplet positions while simultaneously such as emulsions, foams, and grains is the cumulative effect of many dis- crete particle rearrangements [1, 2

  15. PHYSICAL REVIEW E 83, 046707 (2011) From bijels to Pickering emulsions: A lattice Boltzmann study

    E-print Network

    Harting, Jens

    PHYSICAL REVIEW E 83, 046707 (2011) From bijels to Pickering emulsions: A lattice Boltzmann study received 2 February 2011; published 15 April 2011) Particle stabilized emulsions are ubiquitous in the food applicability by studying the transition from a "bicontinuous interfacially jammed emulsion gel" (bijel

  16. Electrostatics at the oilwater interface, stability, and order in emulsions and colloids

    E-print Network

    Leunissen, Mirjam

    Electrostatics at the oil­water interface, stability, and order in emulsions and colloids Mirjam E and surprisingly stable, additive-free, water-in-oil emulsions that can crystallize. For particle-stabilized (``Pickering'') emulsions we find that even ex- tremely hydrophobic, nonwetting particles can be strongly bound

  17. Wide gap Couette flows of dense emulsions: local concentration measurements, and comparison between macroscopic and local

    E-print Network

    Paris-Sud XI, Université de

    Wide gap Couette flows of dense emulsions: local concentration measurements, and comparison between.036307 #12;Abstract Flows of dense emulsions show many complex features among which long range nonlocal the flows of several dense emulsions, with droplet size ranging from 0.3 to 40µm, in a wide gap Couette

  18. Emulsification and Stabilization Mechanisms of O/W Emulsions in the Presence of Chitosan

    E-print Network

    Terentjev, Eugene

    Emulsification and Stabilization Mechanisms of O/W Emulsions in the Presence of Chitosan Linda polyelectrolitic brush on the water side of this interface. We characterize emulsions with varying oil content. Introduction Emulsions are intensely studied because of their potential use in many industrial applications

  19. A STUDY OF THE DIELECTRIC PROPERTIES OF WATER EMULSIONS OBTAINED AFTER A CRYSTALLIZATION/MELTING CYCLE

    E-print Network

    Paris-Sud XI, Université de

    825 A STUDY OF THE DIELECTRIC PROPERTIES OF WATER EMULSIONS OBTAINED AFTER A CRYSTALLIZATION paraffine), obtenues après congélation-fusion, sont comparées avec celles des emulsions d'eau avant tout. Abstract. 2014 The dielectric properties of water emulsions (the continuous medium of which is a mixture

  20. ISSN:1369 7021 Elsevier Ltd 2008APRIL 2008 | VOLUME 11 | NUMBER 418 Designer emulsions

    E-print Network

    Rowat, Amy C.

    ISSN:1369 7021 © Elsevier Ltd 2008APRIL 2008 | VOLUME 11 | NUMBER 418 Designer emulsions using microfluidics An emulsion is a mixture of two immiscible liquids, where one liquid is dispersed in the form of small drops in another liquid that forms a continuous phase1­4. Common types of emulsions include oil

  1. VISCOELASTIC BEHAVIOR OF POLYMER-THICKENED WATER-IN-OIL EMULSIONS

    E-print Network

    Natelson, Douglas

    VISCOELASTIC BEHAVIOR OF POLYMER-THICKENED WATER-IN- OIL EMULSIONS MONTESI PE�A HIRASAKI PASQUALI behavior of emulsions of water dispersed in a lubricant oil base and stabilized with a nonionic surfactant concentration, emulsions with and without polyisobutylene (PIB, MW = 2.1 ± 0.2 x 106 Da) added to the oil phase

  2. Topological rearrangements and stress fluctuations in quasi-two-dimensional hopper flow of emulsions

    E-print Network

    Weeks, Eric R.

    of emulsions Dandan Chen,* Kenneth W. Desmond and Eric R. Weeks Received 2nd May 2012, Accepted 17th August 2012 DOI: 10.1039/c2sm26023a We experimentally study the shear flow of oil-in-water emulsion droplets such as sand, foam, and emulsions behave like elastic solids at rest, and under sufficient applied stress

  3. Forced generation of simple and double emulsions in all-aqueous system Alban Sauret1, 2

    E-print Network

    Paris-Sud XI, Université de

    Forced generation of simple and double emulsions in all-aqueous system Alban Sauret1, 2 and Ho-to-implement method that allows the direct generation of water- in-water (w/w) single emulsions. The method relies on direct perturbation of the pressure that drives the flow of the dispersed phase of the emulsions

  4. Critical Review of Techniques and Methodologies for Characterization of Emulsion Stability

    Microsoft Academic Search

    David Julian Mcclements

    2007-01-01

    The efficient development and production of high quality emulsion-based products depends on knowledge of their physicochemical properties and stability. A wide variety of different analytical techniques and methodologies have been developed to characterize the properties of food emulsions. The purpose of this review article is to provide a critical overview of the most important properties of emulsions that are of

  5. Development and characterisation of tempered cocoa butter emulsions containing up to 60% water

    Microsoft Academic Search

    J. E. Norton; P. J. Fryer; J. Parkinson; P. W. Cox

    2009-01-01

    Cocoa butter water-in-oil emulsions, with up to 60% water, were created using both a high shear mixer and a bench scale margarine line. The high shear mixer gave a stable, fully emulsified emulsion with water content of up to 20%, and the polymorphic form required for good eating qualities was evident from differential scanning calorimetry measurements after the emulsions had

  6. The effect of air sparging on the electrical resolution of water-in-oil emulsions

    Microsoft Academic Search

    P. J. Bailes; P. K. Kuipa

    2001-01-01

    A novel process is described in which the resolution of a stable water-in-oil emulsion is augmented by the simultaneous use of pulsed DC electric fields and mild bubbling of the emulsion with air. The work has indicated that there is a synergistic effect of air sparging on demulsification in the electric field and that the maximum emulsion resolution requires the

  7. The Stability of Aerated Milk Protein Emulsions in the Presence of Small Molecule Surfactants

    Microsoft Academic Search

    B. M. C. Pelan; K. M. Watts; I. J. Campbell; A. Lips

    1997-01-01

    The effects of milk proteins and small molecular surfactants on oil droplet surface coverage and emul- sion stability were studied in model emulsions, and the results were related to the microstructure and physical properties of ice creams. Emulsions became increasingly more stable during partial coalescence at increased surface coverage as the protein concentra- tion was increased. Model emulsions of 20%

  8. Impact of Weighting Agents and Sucrose on Gravitational Separation of Beverage Emulsions

    Microsoft Academic Search

    Ratjika Chanamai; D. Julian McClements

    2000-01-01

    The influence of weighting agents and sucrose on gravitational separation in 1 wt % oil-in-water emulsions was studied by measuring changes in the intensity of backscattered light from the emulsions with height. Emulsions with different droplet densities were prepared by mixing weighting agents (brominated vegetable oil (BVO), ester gum (EG), damar gum (DG), or sucrose acetate isobutyrate (SAIB)) with soybean

  9. Development of a frozen yogurt fortified with a nano-emulsion containing purple rice bran oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to develop and evaluate a frozen yogurt (FY) fortified with a nano-emulsion containing purple rice bran oil (NPRBO). A nano-emulsion with a droplet size range of 150-300 nm was produced by sonication followed by ultra-shear homogenization. The nano-emulsion was mi...

  10. Algorithm of reconstruction for electromagnetic shower analysis in emulsion cloud chambers

    E-print Network

    Paris-Sud XI, Université de

    Algorithm of reconstruction for electromagnetic shower analysis in emulsion cloud chambers Y This note describes an algorithm of reconstruction for electromagnetic cascades in emulsion cloud chambers an algorithm of reconstruction specific to the electromagnetic cascades in emulsion cloud chambers. We will see

  11. Elastohydrodynamic Film Thickness and Tractions for Oil-in-Water Emulsions

    Microsoft Academic Search

    HAIXIA YANG; STEVEN R. SCHMID; THOMAS J. KASUN; RONALD A. REICH

    2004-01-01

    Emulsions, consisting of a small volume of oil dispersed in water in the form of small particles, are popular lubricants for metal rolling and some machine design applications. A number of mechanisms have been suggested for the lubricating behavior of emulsions, among which plate-out, starvation, and dynamic concentration are of particular interest here. At low speeds, the emulsion provides essentially

  12. Recent progress in emulsion technology to study fragmentation reactions of high

    E-print Network

    Boyer, Edmond

    Recent progress in emulsion technology to study fragmentation reactions of high energetic ion beams-8522, Japan Abstract The R&D project to study nuclear fragmentation using emulsion in attempt to im- prove application of hybrid apparatus of emulsion and CR-39, and performing basic study of gold deposition

  13. A stable, radioactive substrate emulsion for assay of I i poprotein I ipase

    Microsoft Academic Search

    Peter Nilsson-Ehle; Michael C. Schotz

    A method is described for the assay of lipoprotein lipase, using a stable, radioactive substrate emulsion. Fatty acid-labeled trioleoylglycerol was emulsified by homoge- nization in glycerol with lecithin as detergent. This anhy- drous emulsion was stable for at least six weeks. Substrate solutions for enzyme assay were prepared by diluting the emulsion with buffer containing serum and albumin. The fatty

  14. Structures of octenylsuccinylated starches: effects on emulsions containing ?-carotene.

    PubMed

    Sweedman, Michael C; Hasjim, Jovin; Schäfer, Christian; Gilbert, Robert G

    2014-11-01

    Starches with different amylopectin contents and different molecular sizes prepared using acid hydrolysis were hydrophobically modified using octenylsuccinic anhydride (OSA). The OSA-modified starches were used as surfactants to stabilize emulsions of ?-carotene and canola oil dispersed in water. The objective of this study is to investigate the relationship between starch molecular structure and the chemical stability of the emulsified ?-carotene, as well as the colloidal stability of emulsion droplets during storage. The oil droplet size in emulsions was smaller when starch had (a) lower hydrodynamic volume (Vh) and (b) higher amylopectin content. The oxidative stability of ?-carotene was similar across samples, with higher results at increased amylopectin content but higher Vh. Steric hindrance to coalescence provided by adsorbed OSA-modified starches appears to be improved by more rigid molecules of higher degree of branching. PMID:25129720

  15. The jamming elasticity of emulsions stabilized by ionic surfactants.

    PubMed

    Scheffold, Frank; Wilking, James N; Haberko, Jakub; Cardinaux, Frédéric; Mason, Thomas G

    2014-07-28

    Oil-in-water emulsions composed of colloidal-scale droplets are often stabilized using ionic surfactants that provide a repulsive interaction between neighboring droplet interfaces, thereby inhibiting coalescence. If the droplet volume fraction is raised rapidly by applying an osmotic pressure, the droplets remain disordered, undergo an ergodic-nonergodic transition, and jam. If the applied osmotic pressure approaches the Laplace pressure of the droplets, then the jammed droplets also deform. Because solid friction and entanglements cannot play a role, as they might with solid particulate or microgel dispersions, the shear mechanical response of monodisperse emulsions can provide critical insight into the interplay of entropic, electrostatic, and interfacial forces. Here, we introduce a model that can be used to predict the plateau storage modulus and yield stress of a uniform charge-stabilized emulsion accurately if the droplet radius, interfacial tension, surface potential, Debye screening length, and droplet volume fraction are known. PMID:24913542

  16. Degradation of kinetically-stable o/w emulsions.

    PubMed

    Capek, Ignác

    2004-03-19

    This article summarizes the studies on the degradation of the thermodynamically unstable o/w (nano)emulsion--a dispersion of one liquid in another, where each liquid is immiscible, or poorly miscible in the other. Emulsions are unstable exhibiting flocculation, coalescence, creaming and degradation. The physical degradation of emulsions is due to the spontaneous trend toward a minimal interfacial area between the dispersed phase and the dispersion medium. Minimizing the interfacial area is mainly achieved by two mechanisms: first coagulation possibly followed by coalescence and second by Ostwald ripening. Coalescence is often considered as the most important destabilization mechanism leading to coursing of dispersions and can be prevented by a careful choice of stabilizers. The molecular diffusion of solubilizate (Ostwald ripening), however, will continuously occur as soon as curved interfaces are present. Mass transfers in emulsion may be driven not only by differences in droplet curvatures, but also by differences in their compositions. This is observed when two or more chemically different oils are emulsified separately and the resulting emulsions are mixed. Compositional ripening involves the exchange of oil molecules between emulsion droplets with different compositions. The stability of the electrostatically- and sterically-stabilized dispersions can be controlled by the charge of the electrical double layer and the thickness of the droplet surface layer formed by non-ionic emulsifier. In spite of the similarities between electrostatically- and sterically-stabilized emulsions, there are large differences in the partitioning of molecules of ionic and non-ionic emulsifiers between the oil and water phases and the thickness of the interfacial layers at the droplet surface. The thin interfacial layer (the electrical double layer) at the surface of electrostatically stabilized droplets does not create any steric barrier for mass transfer. This may not be true for the thick interfacial layer formed by non-ionic emulsifier. The interactive sterically-stabilized oil droplets, however, can favor the transfer of materials within the intermediate agglomerates. The stability of electrosterically-stabilized emulsion is controlled by the ratio of the thickness of the non-ionic emulsifier adsorption layer (delta) to the thickness of the electrical double layer (kappa(-1)) around the oil droplets (delta/(kappa(-1))) = (deltakappa). The monomer droplet degradation can be somewhat depressed by transformation of coarse emulsions to nano-emulsion (miniemulsion) by intensive homogenization and by the addition of a surface active agent (coemulsifier) or/and a water-insoluble compound (hydrophobe). The addition of hydrophobe (hexadecane) to the dispersed phase significantly retards the rate of ripening. A long chain alcohol (coemulsifier) resulted in a marked improvement in stability, as well, which was attributed to a specific interaction between alcohol and emulsifier and to the alcohols tendency to concentrate at the o/w interface to form stronger interfacial film. The rate of ripening, according to the Lifshitz-Slyozov-Wagner (LSW) model, is directly proportional to the solubility of the dispersed phase in the dispersion medium. The increased polarity of the dispersed phase (oil) decreases the stability of the emulsion. The molar volume of solubilizate is a further parameter, which influences the stability of emulsion or the transfer of materials through the aqueous phase. The interparticle interaction is expected to favor the transfer of solubilizate located at the interfacial layer. The kinetics of solubilization of non-polar oils by ionic micelles is strongly related to the aqueous solubility of the oil phase (the diffusion approach), whilst their solubilization into non-ionic micelles can be contributed by interparticle collisions. PMID:15026289

  17. Binding of local anaesthetics to the lipid emulsion Clinoleic™ 20%.

    PubMed

    Evans, J A; Wallis, S C; Dulhunty, J M; Pang, G

    2013-09-01

    Lipid emulsions have been used to treat cardiovascular collapse due to local anaesthetic toxicity. However, there are few data available on the comparative efficiency of the partitioning properties of available lipid emulsions in clinical use. This in vitro study compared the buffering properties of the lipid emulsions Clinoleic™ 20% (Baxter, Old Toongabbie, NSW) and Intralipid® 20% (Fresenius Kabi, Pymble, NSW) using both bupivacaine (Marcain® 0.5%, AstraZeneca, North Ryde, NSW) and ropivacaine (Naropin® 1%, AstraZeneca, North Ryde, NSW). The concentration of anaesthetic in buffer before and after mixing with lipid was quantified using chromatographic analysis. Bupivacaine was more effectively bound by the lipid agents, with a 40% reduction in initial concentration. Ropivacaine demonstrated a 20% reduction in concentration with the addition of lipid agents. Importantly, there was no significant difference between Intralipid and Clinoleic in terms of their buffering behaviour, suggesting equivalent binding efficacy. PMID:23977913

  18. Automated Track Recognition and Event Reconstruction in Nuclear Emulsion

    NASA Technical Reports Server (NTRS)

    Deines-Jones, P.; Cherry, M. L.; Dabrowska, A.; Holynski, R.; Jones, W. V.; Kolganova, E. D.; Kudzia, D.; Nilsen, B. S.; Olszewski, A.; Pozharova, E. A.; Sengupta, K.; Szarska, M.; Trzupek, A.; Waddington, C, J.; Wefel, J. P.; Wilczynska, B.; Wilczynski, H.; Wolter, W.; Wosiek, B.; Wozniak, K.

    1998-01-01

    The major advantages of nuclear emulsion for detecting charged particles are its submicron position resolution and sensitivity to minimum ionizing particles. These must be balanced, however, against the difficult manual microscope measurement by skilled observers required for the analysis. We have developed an automated system to acquire and analyze the microscope images from emulsion chambers. Each emulsion plate is analyzed independently, allowing coincidence techniques to be used in order to reject back- ground and estimate error rates. The system has been used to analyze a sample of high-multiplicity Pb-Pb interactions (charged particle multiplicities approx. 1100) produced by the 158 GeV/c per nucleon Pb-208 beam at CERN. Automatically reconstructed track lists agree with our best manual measurements to 3%. We describe the image analysis and track reconstruction techniques, and discuss the measurement and reconstruction uncertainties.

  19. Synthesis of Fluorosurfactants for Emulsion-Based Biological Applications

    PubMed Central

    2015-01-01

    Microemulsion represents an attractive platform for fundamental and applied biomedical research because the emulsified droplets can serve as millions of compartmentalized micrometer-sized reactors amenable to high-throughput screening or online monitoring. However, establishing stable emulsions with surfactants that are compatible with biological applications remains a significant challenge. Motivated by the lack of commercially available surfactants suitable for microemulsion-based biological assays, this study describes the facile synthesis of a biocompatible fluorosurfactant with nonionic tris(hydroxymethyl)methyl (Tris) polar head groups. We have further demonstrated compatibility of the developed surfactant with diverse emulsion-based applications, including DNA polymeric nanoparticle synthesis, enzymatic activity assay, and bacterial or mammalian cell culture, in the setup of both double- and multiphases of emulsions. PMID:24646088

  20. A Simple Experiment Illustrating the Structure of Association Colloids.

    ERIC Educational Resources Information Center

    Friberg, Stig. E.; Bendiksen, Beverly

    1979-01-01

    The experiment described is intended to illustrate the intermolecular phenomena involved in association colloids. These are normal and inverse micelles and lyotropic liquid crystals. Solubilization, microemulsion and emulsion are discussed. (Author/SA)

  1. Tribology of steel/steel interaction in oil-in-water emulsion; a rationale for lubricity.

    PubMed

    Kumar, Deepak; Daniel, Jency; Biswas, S K

    2010-05-15

    Oil droplets are dispersed in water by an anionic surfactant to form an emulsion. The lubricity of this emulsion in steel/steel interaction is explored in a ball on flat nanotribometer. The droplet size and charge are measured using dynamic light scattering, while the substrate charge density is estimated using the pH titration method. These data are combined to calculate the DLVO forces for the droplets generated for a range of surfactant concentration and two oil to water volume ratios. The droplets have a clear bi-modal size distribution. The study shows that the smaller droplets which experience weak repulsion are situated (at the highest DLVO barrier) much closer to the substrate than the bigger droplets, which experience the same DLVO force, are. We suggest that the smaller droplets thus play a more important role in lubricity than what the bigger droplets do. The largest volume of such small droplets occurs in the 0.5 mM-1 mM range of surfactant concentration and 1% oil to water volume ratio, where the coefficient of friction is also observed to be the least. PMID:20171646

  2. Photoinduced demulsification of emulsions using a photoresponsive gemini surfactant.

    PubMed

    Takahashi, Yutaka; Fukuyasu, Kengo; Horiuchi, Tatsuya; Kondo, Yukishige; Stroeve, Pieter

    2014-01-14

    This Article reports on the influence of light irradiation on the stability of emulsions prepared using a photoresponsive gemini surfactant (C7-azo-C7) having an azobenzene skeleton as a spacer. When mixtures of trans C7-azo-C7 aqueous solution and n-octane are homogenized, stable emulsions are obtained in a specific region of weight fraction and surfactant concentration. Fluorescence microscopy observations using a small amount of fluorescent probes show that the stable emulsions are oil-in-water (O/W)-type. UV irradiation of stable O/W emulsions promotes the cis isomerization of trans C7-azo-C7 and leads to the coalescence of the oil (octane) droplets in the emulsions, that is, demulsification. While the equilibrated interfacial tension (IFT) between aqueous trans C7-azo-C7 solution and octane is almost the same as that between aqueous cis C7-azo-C7 and octane, the occupied area per molecule for C7-azo-C7 at octane/water interface decreases with the cis photoisomerization of trans isomer. Dynamic IFT measurement shows that UV irradiation to the interface between aqueous trans C7-azo-C7 solution and octane brings about an increase in the interfacial tension, indicating that the Gibbs free energy at the interface increases. From these results, the cis isomerization of trans C7-azo-C7 molecules at the O/W interface due to UV irradiation leads to direct contact between the water and octane phases, because of the reduction of molecular area at the interface, and subsequently makes the emulsions demulsified. PMID:24354334

  3. Preparation of acrylate IPN copolymer latexes by radiation emulsion polymerization

    NASA Astrophysics Data System (ADS)

    Wu, Minghong; Zhou, Ruimin; Ma, Zue-Teh; Bao, Borong; Lei, Jianqiu

    1997-03-01

    Radiation-induced and chemical initiation are compared in the initiation of acrylate emulsion copolymer latexes. The particle diameter, distribution and microstructure are influenced by emulsifier concentration, radiation dose and temperature. The results show that the emulsion particle diameter of radiation polymerization is smaller and better distributed in comparison to using chemical polymerization. In addition, interlude polymer net (IPN) core-shell copolymer latexes are observed by transmission electron microscope (TEM). The bounding face of core-shell acrylate copolymmer texes of radiation polymerization is clearer. The morphology of acrylate IPN copolymer latexes is further investigated.

  4. Functional polymeric microparticles engineered from controllable microfluidic emulsions.

    PubMed

    Wang, Wei; Zhang, Mao-Jie; Chu, Liang-Yin

    2014-02-18

    Functional polymeric microparticles with typical sizes of 1-1000 ?m have received considerable attention for many applications. Especially in biomedical fields, polymeric microparticles with advanced functions such as targeted delivery, controlled encapsulation, or "capture and release" show great importance as delivery systems for active molecules and drugs, as imaging agents for analytics and diagnostics, as microreactors for confined bioreactions, and more. Generally, the functions of these microparticles rely on both their structures and the properties of their component materials. Thus, creating unique structures from functional materials provides an important strategy for developing advanced functional polymeric microparticles. Several methods, such as dispersion polymerization, precipitation polymerization, copolymer self-assembly, and phase-separated polymer precipitation can be used to make functional microparticles, but each has limitations, for example, their limited control over the particle size and structure. Using emulsions as templates, however, allows precise control over the size, shape, composition, and structure of the resulting microparticles by tuning those of the emulsions via specific emulsification techniques. Microfluidic methods offer excellent control of emulsion droplets, thereby providing a powerful platform for continuous, reproducible, scalable production of polymeric microparticles with unprecedented control over their monodispersity, structures, and compositions. This approach provides broad opportunities for producing polymeric microparticles with novel structure-property combinations and elaborately designed functions. In this Account, we highlight recent efforts in microfluidic fabrication of advanced polymeric microparticles with well-designed functions for potential biomedical applications, and we describe the development of microfluidic techniques for producing monodisperse and versatile emulsion templates. We begin by describing microparticles made from single emulsions and then describe those from complex multiple emulsions, showing how the resulting microparticles combine novel structures and material properties to achieve their advanced functions. Monodisperse emulsions enable production of highly uniform microparticles of desired sizes to achieve programmed release rates and passive targeting for drug delivery and diagnostic imaging. Phase-separated multiple emulsions allow combination of a variety of functional materials to generate compartmental microparticles including hollow, core-shell, multicore-shell, and hole-shell structures for controlled encapsulation and release, selective capture, and confined bioreaction. We envision that the versatility of microfluidics for microparticle synthesis could open new frontiers and provide promising and exciting opportunities for fabricating new functional microparticles with broad implications for myriad fields. PMID:24199893

  5. Field-Induced Labyrinthine Patterns in Ferrofluid Emulsions

    NASA Astrophysics Data System (ADS)

    Flores, George A.; Ivey, Mark L.; Liu, Jing; Mohebi, M.; Jamasbi, N.

    A ferrofluid emulsion goes through gas — solid phase transition when an external magnetic field is applied. The solid structures are observed as either column, bent-wall, or labyrinthine patterns. The appearance of these different patterns depend upon the rate of the field applied, thickness of the sample cell along the field direction, and the volume fraction of the emulsion droplets used. Using optical microscopy, formed patterns are recorded and analyzed in which a “phase” diagram of the structural transition from column to bent-wall is measured.

  6. Bicontinuous emulsion gels induced by partial coalescence: Kinetics and mechanism

    NASA Astrophysics Data System (ADS)

    Thivilliers, F.; Drelon, N.; Schmitt, V.; Leal-Calderon, F.

    2006-10-01

    We describe a gelation process based on the unrelaxed coalescence of partially crystallised droplets in a primary oil-in-water emulsion. Under the effect of a gentle thermal treatment, fluid emulsions turned into hard gels whose evolution was arrested by the solid nature of the droplets. The kinetic evolution of the bulk elastic modulus G' during the thermal treatment was interpreted within the frame of percolation theory. The experimental data support the conclusion that coalescence involves irreversible bridging between crystallised and melted patches in the thin liquid films.

  7. Microscopic structure of water in a water/oil emulsion.

    PubMed

    Mancinelli, R; Bruni, F; Ricci, M A; Imberti, S

    2013-05-28

    We have determined the microscopic structure of water within a water/oil emulsion, by combining neutron diffraction data, exploiting the isotopic H/D substitution, and a fully atomistic Monte Carlo simulation of a portion of a water droplet, containing the water/oil interface. The dependence of the data on the simulation box size and the reliability of the water-water radial distribution functions are discussed. Although water in the emulsion forms shorter and stronger hydrogen bonds compared to pure bulk water, its overall microscopic structure looks more disordered. PMID:23742489

  8. Impurity mediated nucleation in hexadecane-in-water emulsions

    E-print Network

    Amy Herhold; Deniz Ertas; Alex J. Levine; H. E. King Jr

    1998-11-06

    We report detailed nucleation studies on the liquid-to-solid transition of hexadecane using nearly monodisperse hexadecane-in-water emulsions. A careful consideration of the kinetics of isothermal and nonisothermal freezing show deviations from predictions of classical nucleation theory, if one assumes that the emulsion droplet population is homogeneous. Similar deviations have been observed previously. As an explanation, we propose a novel argument based on the dynamic generation of droplet heterogeneity mediated by mobile impurities. This proposal is in excellent agreement with existing data.

  9. Dynamics of step-emulsification: From a single to a collection of emulsion droplet generators

    NASA Astrophysics Data System (ADS)

    Mittal, Nitesh; Cohen, Céline; Bibette, Jérôme; Bremond, Nicolas

    2014-08-01

    Microfluidics has proven to be an efficient tool for making fine and calibrated emulsion droplets. The parallelization of drop makers is required for producing large amounts. Here, we investigate the generation of emulsion drops along a series of shallow microchannels emerging in a deep one, in other words the step-emulsification process. The dynamics of a single drop maker is first characterized as a function of interfacial tension and viscosities of both phases. The characteristic time scale of drop formation, namely, the necking time that finally sets drop size, is shown to be principally governed by the outer phase viscosity to interfacial tension ratio with a minor correction linked to the viscosity ratio. The step emulsification process experiences a transition of fragmentation regime where both the necking time and drop size suddenly raise. This transition, that corresponds to a critical period of drop formation and thus defines a maximum production rate of small droplets, is observed to be ruled by the viscosity ratio of the two phases. When drops are produced along an array of microchannels with a cross flow of the continuous phase, a configuration comparable to a one-dimensional membrane having rectangular pores, a drop boundary layer develops along the drop generators. In the small drop regime, the local dynamics of drop formation is shown to be independent on the emulsion cross flow. Moreover, we note that the development of the drop boundary layer is even beneficial to homogenize drop size along the production line. On the other hand, in the large drop regime, drop collision can trigger fragmentation and thus lead to size polydispersity.

  10. Encapsulation of Resveratrol Using Water-in-Oil-in-Water Double Emulsions

    Microsoft Academic Search

    Yacine Hemar; Li Jiang Cheng; Christine M. Oliver; Luz Sanguansri; Maryann Augustin

    2010-01-01

    The suitability of water-in-oil-in-water multiple emulsions to encapsulate resveratrol was assessed. Multiple emulsions were\\u000a prepared by emulsifying a primary emulsion (40 wt.%) in water containing 0.5 wt.% sodium caseinate and 0.1 M NaCl. Four primary\\u000a emulsions of canola oil (20 wt.%) stabilized by 8 wt.% polyglycerol polyricinoleate were chosen. The dispersed phase of the\\u000a primary emulsions contained 0.1 M NaCl and either water, 20 wt.% ethanol in

  11. Spectra, composition, and interactions of nuclei with magnet interaction chambers

    NASA Technical Reports Server (NTRS)

    Parneil, T. A.; Derrickson, J. H.; Fountain, W. F.; Roberts, F. E.; Tabuki, T.; Watts, J. W.; Burnett, T. H.; Cherry, M. C.; Dake, S.; Fuki, M.

    1990-01-01

    Emulsion chambers will be flown in the Astromag Facility to measure the cosmic ray composition and spectra to 10 exp 15 eV total energy and to definitively study the characteristics of nucleus-nucleus interactions above 10 exp 12 eV/n. Two configurations of emulsion chambers will be flown in the SCIN/MAGIC experiment. One chamber has an emulsion target and a calorimeter similar to those recently flown on balloons for composition and spectra measurements. The other has an identical calorimeter and a low-density target section optimized for performing rigidity measurements on charged particles produced in interactions. The transverse momenta of charged and neutral mesons, direct hadronic pairs from resonance decays and interference effects, and possible charge clustering in high-density states of matter will be studied.

  12. Direct determination of PB in gasoline emulsions using Ar and Ar-oxygen ICPs

    SciTech Connect

    Brenner, I.B.; Zander, A.; Shkolnik, J.; Kim, S. [Varian Research Center, Palo Alto, CA (United States); [Varian Optical Spectroscopy Instruments, Wood Dale, IL (United States)

    1995-12-31

    Lead in gasoline emulsions was determined by argon and argon-oxygen ICP-AES. Intensity variations of inorganic and organic lead species in aqueous solution and in gasoline and decalin emulsions were studied. In an aqueous solution Pb II intensities were higher than those observed in gasoline and decalin emulsions and were higher in the argon ICP than in an argon-oxygen plasma. Pb intensities were influenced by aerosol flow rate, oxygen doping and emulsion composition, which were all compensated by Y II the internal standard. Pb LODs in the emulsions were not significantly degraded relative to an aqueous solution, and were adequate for the direct determination of lead in gasoline at the mg/kg concentration. The accuracy of Pb determination in spiked gasoline emulsions and in NIST reference fuels was satisfactory. Mg II/Mg I ratios indicate that emulsion plasmas are similar to ICPs containing water only.

  13. The influence of emulsion structure on the Maillard reaction of ghee.

    PubMed

    Newton, Angela E; Fairbanks, Antony J; Golding, Matt; Andrewes, Paul; Gerrard, Juliet A

    2015-04-15

    Food systems, such as cream and butter, have an emulsion or emulsion-like structure. When these food emulsions are heated to high temperatures to make products such as ghee, the Maillard reaction forms a range of volatile flavour compounds. The objective of this paper was to unravel the specific influence of emulsion structure on the Maillard reaction pathways that occur during the cooking of ghee using model systems. Switching the dispersed phase from oil to water provided a means of altering the ratios of volatile compounds produced in the cooked samples. The oil-in-water emulsion generated a volatile compound profile similar to that of the fat containing two phase model matrix, whereas the water-in-oil emulsion produced a different ratio of these compounds. The ability to generate different volatile compound profiles through the use of inverted emulsion structures could point to a new avenue for control of the Maillard reaction in high temperature food systems. PMID:25466150

  14. Oral absorption of a valsartan-loaded spray-dried emulsion based on hydroxypropylmethyl cellulose.

    PubMed

    Baek, In-Hwan; Kim, Jung-Soo; Ha, Eun-Sol; Choo, Gwang-Ho; Cho, Wonkyung; Hwang, Sung-Joo; Kim, Min-Soo

    2014-08-01

    The aim of this study was to develop a novel valsartan-loaded spray-dried emulsion based on hydroxypropylmethyl cellulose (HPMC) with enhanced oral absorption. The valsartan-loaded redispersible dry emulsion was prepared by using a high-pressure homogenization and spray-drying process with water, Capryol 90, HPMC, and different surfactants, based on the results of the solubility study. The spray-dried emulsions formed small and homogeneous emulsions with a mean droplet emulsion size ranging from 133.5 to 152.5nm at the dispersion state in water. The valsartan-loaded redispersible dry emulsion with HPMC/poloxamer 407 showed enhanced pH-independent valsartan release, resulting in a dramatically enhanced oral bioavailability of valsartan compared to the raw material and commercial product. Therefore, a formulation strategy using the redispersible dry emulsion with HPMC/poloxamer 407 is very effective for the development of a new dosage form containing valsartan. PMID:24879921

  15. Hydrophobin coated Boehmite Nanoparticles stabilizing oil in water emulsions

    Microsoft Academic Search

    Martin Reger; Heinz Hoffmann

    Hydrophobin coated Boehmite nanoparticles have been used to establish tooth-paste like, homogenous emulsions. The surface-modified nanoparticles were simply obtained by mixing aqueous solutions of cationic boehmite particles with the anionic hydrophobin H Star Protein B ® (HPB). Surface tension measurements clearly show that 1 wt% Boehmite binds up to 1 wt% HPB. The strong interaction and aggregation of hydrophobin coated

  16. Transdermal delivery of forskolin from emulsions differing in droplet size.

    PubMed

    Sikora, El?bieta; Llinas, Meritxell; Garcia-Celma, Maria Jose; Escribano, Elvira; Solans, Conxita

    2015-02-01

    The skin permeation of forskolin, a diterpene isolated from Coleus forsholii, was studied using oil in water (O/W) emulsions as delivery formulations and also an oil solution for comparative purposes. Two forskolin-loaded emulsions of water/Brij 72:Symperonic A7/Miglyol 812:Isohexadecane, at 0.075wt% forskolin concentration were prepared with the same composition and only differing in droplet size (0.38?m and 10?m). The emulsions showed high kinetic stability at 25°C. In vitro study of forskolin penetration through human skin was carried out using the MicroettePlus(®) system. The concentration of the active in the receptor solution (i.e. ethanol/phosphate buffer 40/60, v/v) was analyzed by high performance liquid chromatography with UV detection. The obtained results showed that forskolin permeation from the emulsions and the oil solution, through human skin, was very high (up to 72.10%), and no effect of droplet size was observed. PMID:25620442

  17. Mannan-stabilized oil-in-water beverage emulsions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The stabilizing effect of spruce galactoglucomannan (GGM) on a model beverage emulsion system was studied and compared to that of guar gum and locust bean gum galactomannans, konjac glucomannan, and corn arabinoxylan. In addition, enzymatic modification was applied on guar gum to examine the effect ...

  18. Texture-structure relationships in foamed dairy emulsions

    Microsoft Academic Search

    D. W. Stanley; H. D. Goff; A. K. Smith

    1996-01-01

    Favorable textural qualities of foamed dairy emulsions result from the successful incorporation of air bubbles surrounded by partially coalesced fat globules into a stable product. Stabilizers, usually hydrocolloids, are often added to improve texture by controlling such factors as, in ice cream, the agglomeration of ice crystals and, in whipped cream, protection of the product against excessive drainage during storage.

  19. Hydrocolloids in emulsions: particle size distribution and interfacial activity

    Microsoft Academic Search

    X Huang; Y Kakuda; W Cui

    2001-01-01

    The emulsification properties of 14 hydrocolloid gums (propylene glycol alginate, gellan, carrageenan, pectin, methylcellulose, microcrystalline cellulose, gum arabic, locust bean gum, guar, xanthan, mustard, flaxseed, fenugreek, oat) were investigated. Gum dispersions were prepared in water (0.5%) and emulsified with 40% oil using a Polytron homogenizer. Emulsion stability was determined by centrifugation and storage time, surface and interfacial tension by Du

  20. Linear rheology of viscoelastic emulsions with interfacial tension

    Microsoft Academic Search

    J. F. Palierne

    1990-01-01

    Emulsions of incompressible viscoelastic materials are considered, in which the addition of an interfacial agent causes the interfacial tension to depend on shear deformation and variation of area. The average complex shear modulus of the medium accounts for the mechanical interactions between inclusions by a self consistent treatment similar to the Lorentz sphere method in electricity. The resulting expression of

  1. Coalescence of Water-in-Shale Oil Emulsions

    Microsoft Academic Search

    V. B. Menon; D. T. Wasan

    1984-01-01

    The coalescence and interfacial behavior of water-in-shale oil emulsions in the presence of chemical additives was studied using photomicrographic analysis. Both the coalescence and flocculation rate constants were determined as a function of the demulsifier concentration. The coalescence rates increased and the interfacial viscosity decreased with an increase in the temperature. These changes are due to the decrease in bulk

  2. Demulsification of dilute oil/water emulsions with organic electrolytes

    SciTech Connect

    Jansson, M.; Pes, M.A. (Institute for Surface Chemistry, Stockholm (Sweden))

    1994-03-15

    Tetraalkylammonium and tetraalkylphosphonium ions induce oil droplet coalescence in dilute oil/water emulsions stabilized by sodium dodecanoate. This was shown by dynamic light-scattering, monitoring oil droplet sizes, and kinetic measurements of oil droplet aggregation. A large ion size, a symmetrical ion geometry and a strongly interacting counterion were found to be important criteria for organic electrolytes to be efficient demulsifiers.

  3. Development of Foamed Emulsion Bioreactor for Air Pollution Control

    E-print Network

    Development of Foamed Emulsion Bioreactor for Air Pollution Control Eunsung Kan, Marc A. Deshusses: 10.1002/bit.10767 Abstract: A new type of bioreactor for air pollution con- trol has been developed used bioreactors for air pollution control. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 240

  4. Interactions between adsorbed macromolecules : measurements on emulsions and liquid films

    Microsoft Academic Search

    Vliet van T

    1977-01-01

    The aim of this study was to gain more insight into the factors, determining the inter- and intramolecular interactions between adsorbed macromolecules. To that end several experimental and theoretical approaches were followed, using well-defined systems. It was shown that these interactions could conveniently be studied by measurements on emulsions and thin free liquid films. Two different macromolecules were used: a

  5. Separation of oil-water emulsion from car washes

    Microsoft Academic Search

    S. Panpanit; C. Visvanathan; S. Muttamara

    The potentials of UF and NF membrane processes have been evaluated for separation of oil water emulsion generated from car washing operations. Using membranes, wastewater can be effectively recycled and fresh water usage could be reduced. The parameters studied were membrane type, emulsifier types, pressure and competing compounds. Both an-ionic and non-ionic emulsifiers were used for the experimental runs. The

  6. PHYSICAL REVIEW E 84, 041404 (2011) Rheology of attractive emulsions

    E-print Network

    , attractive emulsions below random close packing, RCP, can form soft gel-like elastic solids. However, above by the complex shear modulus, G () = G () + iG (), where G is the storage modulus, G is the loss modulus, and is the angular frequency. For droplet volume fractions approaching random close packing of spheres RCP 0

  7. Hydrophobin coated boehmite nanoparticles stabilizing oil in water emulsions.

    PubMed

    Reger, Martin; Hoffmann, Heinz

    2012-02-15

    Hydrophobin coated boehmite nanoparticles have been used to establish tooth-paste like, homogenous emulsions. The surface-modified nanoparticles were simply obtained by mixing aqueous solutions of cationic boehmite particles with the anionic hydrophobin H Star Protein B® (HPB). Surface tension measurements clearly show that 1 wt.% boehmite binds up to 1 wt.% HPB. The strong interaction and aggregation of hydrophobin coated boehmite nanoparticles was proven by Cryo-TEM measurements, too. Interestingly, the combined use of 0.5 wt.% HPB and 0.5 wt.% boehmite as emulsifying agents resulted in very stable, homogenous, high internal phase emulsions (65 wt.% oil) that are stable over months. The established emulsions have also been characterized by rheological measurements. Storage moduli of more than 1000 Pa are characteristic for their high gel-like properties. Furthermore, light microscopy showed an average droplet size close to 1 ?m with low polydispersity. Cryo-SEM confirmed that the hydrophobin coated nanoparticles are located at the interface of the oil droplets and therefore stabilize the emulsion systems. PMID:22129628

  8. Azeotropic Distillation as a Technique for Emulsion Size Reduction

    E-print Network

    Petta, Jason

    Azeotropic Distillation as a Technique for Emulsion Size Reduction Taylor Emanuelle Sweet 2013 Prism/PCCM #12;Overview -Intro- What is Microfluidics? What is Heterogeneous Azeotropic Distillation microns in size and use Binary Heterogeneous Azeotropic Distillation to shrink droplets to 5-10 microns

  9. Intravenous lipid emulsion for treating permethrin toxicosis in a cat

    PubMed Central

    DeGroot, Whitney D.

    2014-01-01

    A 2-year-old cat was presented with acute onset seizures, tremors, and hypersalivation. Permethrin toxicity was diagnosed based on a history of recent flea treatment. Measures were taken to minimize further absorption of permethrin, and methocarbamol and intravenous lipid emulsion were used to control tremors. The cat recovered and was discharged within 42 h. PMID:24381347

  10. Control of the volumetric and viscosity ratios of iron-silicate emulsion on the core formation process

    NASA Astrophysics Data System (ADS)

    Sato, M.; Sumita, I.

    2007-12-01

    In a vigorously convecting magma ocean, shearing motion would cause an iron-silicate emulsion to form. Iron or silicate droplets would eventually settle or rise to form the core and the mantle. Volumetric and viscosity ratios of the droplet to continuous phase can vary but how these control the phase separation process is not understood. Here we report on a series of experiments using an oil droplet in water or hydroxyethylcellulose solution (all Newtonian) to study how these ratios govern the gravitational phase separation process. First, we changed the volumetric fraction of oil. From tracking the boundary between the layer of solution and emulsion, we find that the initial phase separation rate depends strongly on oil fraction, and can be modelled by a buoyancy driven permeable flow using the Blake-Kozeny-Carman permeability formula. Next, we changed the droplet to continuous phase viscosity ratio (?) and find that there are two distinct regimes with different styles of phase separation. Cases with ? < 100 are characterized by a sharp lower boundary and a vertically homogeneous mixture layer. On the other hand, cases with ? > 100 are characterized by a diffuse lower boundary and a large vertical gradient of composition resulting from efficient droplet coalescence. As a result, polyhedral foam structure develops at the top of the mixture layer which is slow to rupture and to transform into a uniform oil layer. We interpret these differences to arise from a faster coalescence rate relative to the separation rate at large ?, where the droplet deformation which inhibits coalescence becomes very small. We simultaneously measured electrical resistivity in order to monitor the temporal change of the mean composition in the mixture layer and found that the measurements were consistent with the visual observation. To summarize, we find that the separation rate is controlled by the permeable flow velocity, whereas the vertical compositional structure within the emulsion layer is controlled by the viscosity ratio. If the above viscosity ratio criterion can be applied to silicate-iron emulsion, the case where iron percolates through silicate droplets (? >> 1) would yield a strongly stratified mantle, compared to the case where iron droplets sink (? << 1). Future separation experiment using iron-silicate emulsion is needed to confirm this. Sato, M. and Sumita, I., Experiments on gravitational phase separation of binary immiscible fluids, J. Fluid Mech., (in press)

  11. Selective removal of erythromycin by magnetic imprinted polymers synthesized from chitosan-stabilized Pickering emulsion.

    PubMed

    Ou, Hongxiang; Chen, Qunhui; Pan, Jianming; Zhang, Yunlei; Huang, Yong; Qi, Xueyong

    2015-05-30

    Magnetic imprinted polymers (MIPs) were synthesized by Pickering emulsion polymerization and used to adsorb erythromycin (ERY) from aqueous solution. The oil-in-water Pickering emulsion was stabilized by chitosan nanoparticles with hydrophobic Fe3O4 nanoparticles as magnetic carrier. The imprinting system was fabricated by radical polymerization with functional and crosslinked monomer in the oil phase. Batches of static and dynamic adsorption experiments were conducted to analyze the adsorption performance on ERY. Isotherm data of MIPs well fitted the Freundlich model (from 15°C to 35°C), which indicated heterogeneous adsorption for ERY. The ERY adsorption capacity of MIPs was about 52.32?mol/g at 15°C. The adsorption kinetics was well described by the pseudo-first-order model, which suggested that physical interactions were primarily responsible for ERY adsorption. The Thomas model used in the fixed-bed adsorption design provided a better fit to the experimental data. Meanwhile, ERY exhibited higher affinity during adsorption on the MIPs compared with the adsorption capacity of azithromycin and chloramphenicol. The MIPs also exhibited excellent regeneration capacity with only about 5.04% adsorption efficiency loss in at least three repeated adsorption-desorption cycles. PMID:25704432

  12. NUCLEAR PHYSICS: Helium production from 84Kr— and 197Au-emulsion interactions at high energies

    NASA Astrophysics Data System (ADS)

    Zhang, Dong-Hai; Cheng, Jin-Xia; Cheng, Bin; Wang, Fang; Wang, Qi; Zhang, Hai-Qing; Xu, Rong; Jia, Hui-Ming; Li, Xue-Qin

    2009-02-01

    The properties of the relativistic helium fragments produced in interactions of 84Kr at 1.8 A GeV and 197Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from various projectiles with emulsion collisions at different energies. It is found that the multiplicity distribution of helium projectile fragments (HPFs) is well described by the Koba-Nielsen-Olesen (KNO) scaling presentation. The second Mueller moment f2 of the HPF multiplicity distribution is independent of the projectile energy for the same projectile, but it is dependent on the projectile mass number. The value of f2 increases with the increase of projectile mass number Ap. The negative value of f2, when Ap < 69, means that the emission of HPFs is anticorrelated, but positive value of f2, when Ap > 69, refers to that the emission of HPFs is correlated. The non-zero f2 moment in this experiment implies the strong correlation existing between the HPFs.

  13. Selective separation of lambdacyhalothrin by porous/magnetic molecularly imprinted polymers prepared by Pickering emulsion polymerization.

    PubMed

    Hang, Hui; Li, Chunxiang; Pan, Jianming; Li, Linzi; Dai, Jiangdong; Dai, Xiaohui; Yu, Ping; Feng, Yonghai

    2013-10-01

    Porous/magnetic molecularly imprinted polymers (PM-MIPs) were prepared by Pickering emulsion polymerization. The reaction was carried out in an oil/water emulsion using magnetic halloysite nanotubes as the stabilizer instead of a toxic surfactant. In the oil phase, the imprinting process was conducted by radical polymerization of functional and cross-linked monomers, and porogen chloroform generated steam under the high reaction temperature, which resulted in some pores decorated with easily accessible molecular binding sites within the as-made PM-MIPs. The characterization demonstrated that the PM-MIPs were porous and magnetic inorganic-polymer composite microparticles with magnetic sensitivity (M(s) = 0.7448 emu/g), thermal stability (below 473 K) and magnetic stability (over the pH range of 2.0-8.0). The PM-MIPs were used as a sorbent for the selective binding of lambdacyhalothrin (LC) and rapidly separated under an external magnetic field. The Freundlich isotherm model gave a good fit to the experimental data. The adsorption kinetics of the PM-MIPs was well described by pseudo-second-order kinetics, indicating that the chemical process could be the rate-limiting step in the adsorption of LC. The selective recognition experiments exhibited the outstanding selective adsorption effect of the PM-MIPs for target LC. Moreover, the PM-MIPs regeneration without significant loss in adsorption capacity was demonstrated by at least four repeated cycles. PMID:23894024

  14. Comparative studies of salinomycin-loaded nanoparticles prepared by nanoprecipitation and single emulsion method.

    PubMed

    Wang, Qin; Wu, Puyuan; Ren, Wei; Xin, Kai; Yang, Yang; Xie, Chen; Yang, Chenchen; Liu, Qin; Yu, Lixia; Jiang, Xiqun; Liu, Baorui; Li, Rutain; Wang, Lifeng

    2014-01-01

    To establish a satisfactory delivery system for the delivery of salinomycin (Sal), a novel, selective cancer stem cell inhibitor with prominent toxicity, gelatinase-responsive core-shell nanoparticles (NPs), were prepared by nanoprecipitation method (NR-NPs) and single emulsion method (SE-NPs). The gelatinase-responsive copolymer was prepared by carboxylation and double amination method. We studied the stability of NPs prepared by nanoprecipitation method with different proportions of F68 in aqueous phase to determine the best proportion used in our study. Then, the NPs were prepared by nanoprecipitation method with the best proportion of F68 and single emulsion method, and their physiochemical traits including morphology, particle size, zeta potential, drug loading content, stability, and in vitro release profiles were studied. The SE-NPs showed significant differences in particle size, drug loading content, stability, and in vitro release profiles compared to NR-NPs. The SE-NPs presented higher drug entrapment efficiency and superior stability than the NR-NPs. The drug release rate of SE-NPs was more sustainable than that of the NR-NPs, and in vivo experiment indicated that NPs could prominently reduce the toxicity of Sal. Our study demonstrates that the SE-NPs could be a satisfactory method for the preparation of gelatinase-responsive NPs for intelligent delivery of Sal. PMID:25147486

  15. Comparative studies of salinomycin-loaded nanoparticles prepared by nanoprecipitation and single emulsion method

    PubMed Central

    2014-01-01

    To establish a satisfactory delivery system for the delivery of salinomycin (Sal), a novel, selective cancer stem cell inhibitor with prominent toxicity, gelatinase-responsive core-shell nanoparticles (NPs), were prepared by nanoprecipitation method (NR-NPs) and single emulsion method (SE-NPs). The gelatinase-responsive copolymer was prepared by carboxylation and double amination method. We studied the stability of NPs prepared by nanoprecipitation method with different proportions of F68 in aqueous phase to determine the best proportion used in our study. Then, the NPs were prepared by nanoprecipitation method with the best proportion of F68 and single emulsion method, and their physiochemical traits including morphology, particle size, zeta potential, drug loading content, stability, and in vitro release profiles were studied. The SE-NPs showed significant differences in particle size, drug loading content, stability, and in vitro release profiles compared to NR-NPs. The SE-NPs presented higher drug entrapment efficiency and superior stability than the NR-NPs. The drug release rate of SE-NPs was more sustainable than that of the NR-NPs, and in vivo experiment indicated that NPs could prominently reduce the toxicity of Sal. Our study demonstrates that the SE-NPs could be a satisfactory method for the preparation of gelatinase-responsive NPs for intelligent delivery of Sal. PMID:25147486

  16. Oil components modulate physical characteristics and function of the natural oil emulsions as drug or gene delivery system.

    PubMed

    Chung, H; Kim, T W; Kwon, M; Kwon, I C; Jeong, S Y

    2001-04-28

    Oil-in-water (o/w) type lipid emulsions were formulated by using 18 different natural oils and egg phosphatidylcholine (egg PC) to investigate how emulsion particle size and stability change with different oils. Cottonseed, linseed and evening primrose oils formed emulsions with very large and unstable particles. Squalene, light mineral oil and jojoba bean oil formed stable emulsions with small particles. The remaining natural oils formed moderately stable emulsions. Emulsions with smaller initial particle size were more stable than those with larger particles. The correlation between emulsion size made with different oils and two physical properties of the oils was also investigated. The o/w interfacial tension and particle size of the emulsion were inversely proportional. The effect of viscosity was less pronounced. To study how the oil component in the emulsion modulates the in vitro release characteristics of lipophilic drugs, three different emulsions loaded with two different drugs were prepared. Squalene, soybean oil and linseed oil emulsions represented the most, medium and the least stable systems, respectively. For the lipophilic drugs, release was the slowest from the most stable squalene emulsion, followed by soybean oil and then by linseed oil emulsions. Cationic emulsions were also prepared with the above three different oils as gene carriers. In vitro transfection activity was the highest for the most stable squalene emulsion followed by soybean oil and then by linseed oil emulsions. Even though the in vitro transfection activity of emulsions were lower than the liposome in the absence of serum, the activity of squalene emulsion, for instance, was ca. 30 times higher than that of liposome in the presence of 80% (v/v) serum. In conclusion, the choice of oil component in o/w emulsion is important in formulating emulsion-based drug or gene delivery systems. PMID:11295226

  17. Lipid emulsions – Guidelines on Parenteral Nutrition, Chapter 6

    PubMed Central

    Adolph, M.; Heller, A. R.; Koch, T.; Koletzko, B.; Kreymann, K. G.; Krohn, K.; Pscheidl, E.; Senkal, M.

    2009-01-01

    The infusion of lipid emulsions allows a high energy supply, facilitates the prevention of high glucose infusion rates and is indispensable for the supply with essential fatty acids. The administration of lipid emulsions is recommended within ?7 days after starting PN (parenteral nutrition) to avoid deficiency of essential fatty acids. Low-fat PN with a high glucose intake increases the risk of hyperglycaemia. In parenterally fed patients with a tendency to hyperglycaemia, an increase in the lipid-glucose ratio should be considered. In critically ill patients the glucose infusion should not exceed 50% of energy intake. The use of lipid emulsions with a low phospholipid/triglyceride ratio is recommended and should be provided with the usual PN to prevent depletion of essential fatty acids, lower the risk of hyperglycaemia, and prevent hepatic steatosis. Biologically active vitamin E (?-tocopherol) should continuously be administered along with lipid emulsions to reduce lipid peroxidation. Parenteral lipids should provide about 25–40% of the parenteral non-protein energy supply. In certain situations (i.e. critically ill, respiratory insufficiency) a lipid intake of up to 50 or 60% of non-protein energy may be reasonable. The recommended daily dose for parenteral lipids in adults is 0.7–1.3 g triglycerides/kg body weight. Serum triglyceride concentrations should be monitored regularly with dosage reduction at levels >400 mg/dl (>4.6 mmol/l) and interruption of lipid infusion at levels >1000 mg/dl (>11.4 mmol/l). There is little evidence at this time that the choice of different available lipid emulsions affects clinical endpoints. PMID:20049078

  18. Relativistic Vlasov-Uehling-Uhlenbeck Equation for Nucleus-Nucleus Collisions

    E-print Network

    LI, Q.; Wu, J. Q.; Ko, Che Ming.

    1989-01-01

    these other mesons, we neglect them in the following for simplicity. The Lagrangian density in the Walecka model is given by L (x)=g[y"(it)?g, V??)?(m g, P)]g- + , ' ( tJ?tti tJ"p ?m,p ) ?,' F" F?,+??,' m ~ Vu V??, (1) where F?.=a?v.?a.V?. The masses... m, m?and I, are for the nucleon, the scalar meson, and the vector meson, respectively; g, and g, are the coupling constants. The Green's function for the nu- cleon is defined as usual by iG (x?x~)= ( ~ T[f(x, )g(x~)]~ ), where T is the time...

  19. Multiple pion and kaon production in high energy nucleus-nucleus collisions: measurements versus specific models

    NASA Astrophysics Data System (ADS)

    Guptaroy, P.; de, Bh.; Bhattacharyya, S.; Bhattacharyya, D. P.

    The pion and kaon rapidity densities and the nature of kaon-pion ratios offer two very prominent and crucial physical observables on which modestly sufficient data for heavy nucleus collisions are available to date. In the light of two sets of models - one purely phenomenological and the other with a modest degree of a dynamical basis - we try to examine the state of agreement between calculations and experimental results obtainable from the past and the latest measurements. Impact and implications of all these would also finally be spelt out.

  20. Pionic freeze-out hypersurfaces in relativistic nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    Anchishkin, D.; Vovchenko, V.; Csernai, L. P.

    2013-01-01

    The space-time structure of the multipion system created in central relativistic heavy-ion collisions is investigated. Using the microscopic transport model UrQMD we determine the freeze-out hypersurface from the equation on pion density n(t,r)=nc. It turns out that for proper value of the critical energy density ?c equation ?(t,r)=?c gives the same freeze-out hypersurface. It is shown that for big enough collision energies Ekin?40A GeV (s?8A GeV) the multipion system at a time moment ? ceases to be one connected unit but splits up into two separate spatial parts (drops), which move in opposite directions from one another with velocities which approach the speed of light with an increase of collision energy. This time ? is approximately invariant of the collision energy, and the corresponding ?= const. hypersurface can serve as a benchmark for the freeze-out time or the transition time from the hydrostage in hybrid models. The properties of this hypersurface are discussed.

  1. Multi-particle correlation observables in high energy nucleus-nucleus collisions

    SciTech Connect

    Stock, R.

    1981-01-01

    Global features of exclusively measured events, including number correlations and vector correlations, and hybrid analysis of measurements of one or two specific fragments like spectator nuclei, high transverse momentum particles, polarization of one particle, etc., are considered. (GHT)

  2. Search for a Signal on QCD Critical Point in Central Nucleus-Nucleus Collisions

    E-print Network

    Suleymanov, M K; Ahmed, K; Haseeb, Mahnaz Q; Tahir, Farida; Huseynaliyev, Y H; Ajaz, M; Khan, K H; Wazir, Z

    2008-01-01

    We discuss that the QCD critical point could appear in central collisions in percolation cluster. We suggest using the nuclear transparency effect and the one of the light nuclear production to identify the critical point.

  3. Search for a Signal on QCD Critical Point in Central Nucleus-Nucleus Collisions

    E-print Network

    M. K. Suleymanov; E. U. Khan; K. Ahmed; Mahnaz Q. Haseeb; Farida Tahir; Y. H. Huseynaliyev; M. Ajaz; K. H. Khan; Z. Wazir

    2008-04-19

    We discuss that the QCD critical point could appear in central collisions in percolation cluster. We suggest using the nuclear transparency effect and the one of the light nuclear production to identify the critical point.

  4. Ratios of heavy baryons to heavy mesons in relativistic nucleus-nucleus collisions

    E-print Network

    Oh, Yongseok; Ko, Che Ming; Lee, Su Houng; Yasui, Shigehiro.

    2009-01-01

    Heavy baryon/meson ratios Lambda(c)/D(0) and Lambda(b)/(B) over bar (0) in relativistic heavy ion collisions are studied in the quark coalescence model. For heavy baryons, we include production from coalescence of heavy quarks with free light quarks...

  5. Systematics of the release of residual nuclei from relativistic nucleus-nucleus interactions

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Israel, M. H.; Klarmann, J.; Garrard, T. L.; Kertzmann, M. P.

    1987-01-01

    Relativistic nuclei of krypton, xenon, holmium, and gold, accelerated in a partially stripped state to a maximum rigidity of about 5.6 GeV, interacting with targets of aluminum, carbon, and polyethylene are examined. For each projectile and target combination, determinations are made for the total and partial charge changing cross sections for the production of lighter fragments. From these measurements, a new representation of the dependence of the total charge changing cross sections on beam and target charge is developed. Simple representations of the variation of the partial cross sections were identified with the charge of the produced fragments and shown to be dependent on the charge and energy of the beam. The fission of gold nuclei at high energies in these various targets has also been studied.

  6. Schroedinger cats, quantum slings and azimuthal effects in nucleus-nucleus collisions

    E-print Network

    I. M. Dremin; V. I. Man'ko

    1998-07-21

    Confinement of a chromodynamical string can result in specific effects in scattering processes and multiparticle production. In particular, due to its rotation secondary fragments of the splitting apart string can move like stones thrown from a sling. That would be detected as the azimuthal asymmetry of particle distributions in individual events. Thus we propose to explain the elliptic flow observed in AA-collisions as a sling-effect. It can provide information about confinement of quarks inside particles or binding forces in nuclei. Nonclassical states of the created particles like the Schroedinger cats are produced. Some classical and quantum-mechanical estimates of possible effects are given. Experimental facts which can be used for their verification are discussed.

  7. Preparation, characterization, and in vitro gastrointestinal digestibility of oil-in-water emulsion-agar gels.

    PubMed

    Wang, Zheng; Neves, Marcos A; Kobayashi, Isao; Uemura, Kunihiko; Nakajima, Mitsutoshi

    2013-01-01

    Soybean oil-in-water (O/W) emulsion-agar gel samples were prepared and their digestibility evaluated by using an in vitro gastrointestinal digestion model. Emulsion-agar sols were obtained by mixing the prepared O/W emulsions with a 1.5 wt % agar solution at 60 °C, and their subsequent cooling at 5 °C for 1 h formed emulsion-agar gels. Their gel strength values increased with increasing degree of polymerization of the emulsifiers, and the relative gel strength increased in the case of droplets with an average diameter smaller than 700 nm. Flocculation and coalescence of the released emulsion droplets depended strongly on the emulsifier type; however, the emulsifier type hardly affected the ?-potential of emulsion droplets released from the emulsion-agar gels during in vitro digestion. The total FFA content released from each emulsion towards the end of the digestion period was nearly twice that released from the emulsion-agar gel, indicating that gelation of the O/W emulsion may have delayed lipid hydrolysis. PMID:23470750

  8. Upgrade of the ALICE Experiment: Letter Of Intent

    NASA Astrophysics Data System (ADS)

    Abelev, B.; ALICE Collaboration; et al.

    2014-08-01

    ALICE (A Large Ion Collider Experiment) is studying the physics of strongly interacting matter, and in particular the properties of the Quark-Gluon Plasma (QGP), using proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN LHC (Large Hadron Collider). The ALICE Collaboration is preparing a major upgrade of the experimental apparatus, planned for installation in the second long LHC shutdown in the years 2018-2019. These plans are presented in the ALICE Upgrade Letter of Intent, submitted to the LHCC (LHC experiments Committee) in September 2012. In order to fully exploit the physics reach of the LHC in this field, high-precision measurements of the heavy-flavour production, quarkonia, direct real and virtual photons, and jets are necessary. This will be achieved by an increase of the LHC Pb-Pb instant luminosity up to 6×1027 cm-2s-1 and running the ALICE detector with the continuous readout at the 50 kHz event rate. The physics performance accessible with the upgraded detector, together with the main detector modifications, are presented.

  9. Laboratory Investigations in Support of Carbon Dioxide-in-Water Emulsions Stabilized by Fine Particles for Ocean and Geologic Sequestration of Carbon Dioxide

    SciTech Connect

    Dan Golomb; Eugene Barry; David Ryan

    2006-07-08

    This semi-annual progress report includes our latest research on deep ocean sequestration of CO{sub 2}-in-Water (C/W) emulsions stabilized by pulverized limestone (CaCO{sub 3}). We describe a practical system that could be employed for the release of a dense C/W emulsion. The heart of the system is a Kenics-type static mixer. The testing and evaluation of a static mixer in the NETL High-Pressure Water Tunnel Facility was described in the previous semi-annual report. The release system could be deployed from a floating platform over the open ocean, or at the end of an off-shore pipe laying on the continental slope. Because the emulsion is much denser than ambient seawater, modeling shows that upon release the plume will sink much deeper from the injection point, increasing the sequestration time for CO{sub 2}. When released in the open ocean, a plume containing the output of a 500 MW{sub el} coal-fired power plant will typically sink hundreds of meters below the injection point. When released from a pipe on the continental shelf, the plume will sink about twice as much because of the limited entrainment of ambient seawater when the plume flows along the sloping seabed. Furthermore, the plume is slightly alkaline, not acidic. The disadvantage is that the creation of the emulsion requires significant amounts of pulverized limestone, on the order of 0.5-0.75 weight ratio of limestone to CO{sub 2}. While pulverized limestone with particle size appropriate for creating C/W emulsions can be purchased for $38 per ton, it is shown in this report that it may be more economic to purchase raw limestone from quarries and pulverize it in situ using grinding mills. In this case the major cost elements are the capital and operating costs of the grinding mills, resulting in a total cost of about $11 per ton of pulverized limestone, including the cost of raw material and shipping. Because we need approximately 0.75 ton of pulverized limestone per ton of liquid CO2 to create a stable C/W emulsion, the total cost of preparing the emulsion on site is about $8.5 per ton of liquid CO{sub 2}, not including the cost of the emulsion mixer. Currently, the cost estimates of capturing and liquefying CO{sub 2} at a coal-fired power plant range from $15 to 75/t CO{sub 2}. Thus, the preparation of C/W emulsions stabilized by pulverized limestone particles would add about 10 to 50% to the capture cost of CO{sub 2}. At this juncture the primary research objectives of this Co-operative Agreement are shifting toward geologic sequestration of carbon dioxide. Experiments are underway to create micro-emulsions of CO{sub 2}-in-Water (C/W) and Water-in-CO{sub 2} (W/C) stabilized by ultrafine particles ranging from sub-micrometer to a few micrometer in size. Such microemulsions are expected to readily penetrate deep geologic formations, such as porous sedimentary layers, including saline aquifers and semi-depleted oil and gas fields. Injections of (C/W) and (W/C) type micro-emulsions may prove to be less prone to leakage from the formations compared to injections of neat liquid or supercritical CO{sub 2}.

  10. Fast parallelized kalman filter based reconstruction of charged particle trajectories for the compressed baryonic matter experiment on a many-core server at the laboratory of information technologies, JINR

    NASA Astrophysics Data System (ADS)

    Ablyazimov, T. O.; Zyzak, M. V.; Ivanov, V. V.; Kisel, P. I.

    2014-07-01

    The charged particle trajectory online reconstruction in the Compressed Baryonic Matter (CBM) experiment (GSI, Germany) is an extremely difficult task. It is conditioned by a high rate of the ion beam-tar-get collisions (up to 107/s), high track multiplicity in each nucleus-nucleus collision (up to 1000 particles), and charged-particle trajectory registration with the coordinate detectors located in a highly inhomogeneous magnetic field. Such a problem could be solved only by using modern high-performance computers. This work scrutinizes a Kalman filter based track reconstruction algorithm implemented using different parallelization approaches. To perform the analysis, a many-core hybrid server with two Intel Xeon X5660 CPUs and a NVidia GTX 480 GPU (JINR LIT) was used.

  11. Metal-Silicate Differentiation from a Metal Pond Emulsion during Core Formation

    NASA Astrophysics Data System (ADS)

    Fleck, J.; Weeraratne, D. S.

    2011-12-01

    The terrestrial planets demonstrate a heavy bombardment of impacts in their early formation history. Impacts are violent, energetic collisions that may melt the surface and/or cause segregation of impactor material including silicates and liquid metal iron. Although theoretical studies have been done with conceptual models for metal diapir descent to form terrestrial planetary cores, physical or computer modeling studies are scarce due to the strong variations in physical properties between liquid metals and solid silicates. We use laboratory fluid experiments to study core formation processes using liquid metal gallium and high viscosity glucose syrup which provide the buoyancy ratios expected for planetary interiors and low Reynolds number flow dynamics. Preliminary results indicate that the physical process of sinking metal diapirs form trailing conduits that may drag low density surface magmatic material to the base of the mantle. The low density material collects, grows at the base of the box, and rises back to the surface. We compare two cases of a pond made of 1) liquid metal emulsion and 2) a smooth coalesced metal pond. We find that emulsion experiments entrain greater amounts of low density fluid to the base of the box. Once the metal diapir reaches the base, conduit material exhibits flow reversal to return buoyantly to the surface. In the case of coalesced liquid metal diapirs, low density conduit material returns to the surface through the pre-established conduit. In the emulsion diapir case, we observe the formation of a new thermo-chemical buoyant plume that grows, exits the conduit, and travels along a new pathway to the surface. Metal plume descent and chemical plume rise velocities are consistent with Stokes velocity. Estimates of metal-silicate plume sinking time and thermo-chemical plume rise time for terrestrial planetary interiors are provided. We suggest the observation of a thermo-chemical plume as a source for orogeny at the surface of terrestrial planets that may have produced the first mantle plumes and early volcanoes during core forming events.

  12. High energy primary electron spectrum observed by the emulsion chamber

    NASA Technical Reports Server (NTRS)

    Nishimura, J.; Fujii, M.; Aizu, H.; Hiraiwa, N.; Taira, T.; Kobayashi, T.; Niu, K.; Koss, T. A.; Lord, J. J.; Golden, R. L.

    1978-01-01

    A detector of the emulsion chamber type is used to measure the energy spectrum of cosmic-ray electrons. Two large emulsion chambers, each having an area of 40 by 50 sq cm, are exposed for about 25.5 hr at an average pressure altitude of 3.9 mbar. About 500 high-energy cascades (no less than about 600 GeV) are detected by searching for dark spots on the X-ray films. A power-law energy dependence formula is derived for the spectrum of primary cosmic-ray electrons in the energy region over 100 GeV. The results are in good agreement with the transition curves obtained previously by theoretical and Monte Carlo calculations.

  13. Lateral distortions of electromagnetic cascades in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Porter, L. G.; Levit, L. B.; Jones, W. V.; Huggett, R. W.; Barrowes, S. C.

    1975-01-01

    Electromagnetic cascades in a lead-emulsion chamber have been studied to determine the effect of air gaps on the upstream sides of the emulsions. Such air gaps cause a change in the form of the radial distribution of electron tracks, making cascades appear older and giving incorrect energy estimates. The number of tracks remaining within a radius r was found to vary as exp(-g/G), where g is the gap thickness. The characteristic gap thickness in mm is G = 3.04 + 1.30 ln (Err per GeV per sq mm) where E is the energy of the initiating gamma ray. Use of this relation provides a significant correction to cascade-energy estimates and allows one to calculate the effect of different gap thicknesses on the energy threshold for visual detection of cascades.

  14. $^8$He nuclei stopped in nuclear track emulsion

    E-print Network

    D. A. Artemenkov; A. A. Bezbakh; V. Bradnova; M. S. Golovkov; A. V. Gorshkov; G. Kaminsky; N. K. Kornegrutsa; S. A. Krupko; K. Z. Mamatkulov; R. R. Kattabekov; V. V. Rusakova; R. S. Slepnev; R. Stanoeva; S. V. Stepantsov; A. S. Fomichev; V. Chudoba; P. I. Zarubin; I. G. Zarubina

    2014-10-20

    The fragment separator ACCULINNA in the G. N. Flerov Laboratory of Nuclear Reactions of JINR was used to expose a nuclear track emulsion to a beam of radioactive $^{8}$He nuclei of energy of 60 MeV and enrichment of about 80%. Measurements of decays of $^{8}$He nuclei stopped in the emulsion allow one to evaluate possibilities of $\\alpha$-spectrometry and to observe a thermal drift of $^{8}$He atoms in matter. Knowledge of the energy and emission angles of $\\alpha$-particles allows one to derive the energy distribution of $\\alpha$-decays Q$_{2\\alpha}$. The presence of a "tail" of large values Q$_{2\\alpha}$ is established. The physical reason for the appearance of this "tail" in the distribution Q$_{2\\alpha}$ is not clear. Its shape could allow one to verify calculations of spatial structure of nucleon ensembles emerging as $\\alpha$-pairs of decays via the state $^8$Be$_{2+}$.

  15. On the transport of emulsions in porous media

    SciTech Connect

    Cortis, Andrea; Ghezzehei, Teamrat A.

    2007-06-27

    Emulsions appear in many subsurface applications includingbioremediation, surfactant-enhanced remediation, and enhancedoil-recovery. Modeling emulsion transport in porous media is particularlychallenging because the rheological and physical properties of emulsionsare different from averages of the components. Current modelingapproaches are based on filtration theories, which are not suited toadequately address the pore-scale permeability fluctuations and reductionof absolute permeability that are often encountered during emulsiontransport. In this communication, we introduce a continuous time randomwalk based alternative approach that captures these unique features ofemulsion transport. Calculations based on the proposed approach resultedin excellent match with experimental observations of emulsionbreakthrough from the literature. Specifically, the new approach explainsthe slow late-time tailing behavior that could not be fitted using thestandard approach. The theory presented in this paper also provides animportant stepping stone toward a generalizedself-consistent modeling ofmultiphase flow.

  16. Fabrication of Rod-Coil Nanocomposites via Emulsion Technique

    NASA Astrophysics Data System (ADS)

    Rossi, Gregory; Beaucage, Gregory; Vaia, Richard; Dang, Thuy

    2001-03-01

    There is increasing technological interest in polymers reinforced by nanoparticles because of their potential to provide enhanced mechanical properties, decreased permeability and flammability, as well as increased conductivity. Emulsion polymerization offers a viable, flexible route for nanocomposite fabrication from nanoscale spheres, rods, and plates. Combining emulsion generated poly(methyl methacrylate) (PMMA) particles that are ionically stabilized in aqueous solution with a dispersion of nanoparticles of opposite sense results in an interfacial exchange reaction and co-precipitation. The rod-coil nanocomposites are composed of fully conjugated sulfonated phenylene benzobisimidazole polymer (sPBI) with pendant PMMA chains. Synthesis and characterization of sPBI-PMMA nanocomposites with increasing nanoparticle content using reactive and non-reactive emulsifiers are discussed, and related according to their inherent physical properties.

  17. Intralipid emulsion treatment as an antidote in lipophilic drug intoxications.

    PubMed

    Eren Cevik, Sebnem; Tasyurek, Tanju; Guneysel, Ozlem

    2014-09-01

    Intravenous lipid emulsion (ILE) is a lifesaving treatment of lipophilic drug intoxications. Not only does ILE have demonstrable efficacy as an antidote to local anesthetic toxicity, it is also effective in lipophilic drug intoxications. Our case series involved 10 patients with ingestion of different types of lipophilic drugs. Intravenous lipid emulsion treatment improved Glasgow Coma Scale or blood pressure and pulse rate or both according to the drug type. Complications were observed in 2 patients (minimal change pancreatitis and probable ILE treatment-related fat infiltration in lungs). In our case series, ILE was used for different lipophilic drug intoxications to improve cardiovascular and neurologic symptoms. According to the results, it was found that ILE treatment is a lifesaving agent in lipophilic drug intoxications and it can be used in unconscious patients who have cardiac and/or neurologic symptoms but no history of a specific drug ingestion. PMID:24974371

  18. Shear Induced Dynamics of Polydisperse Jammed Emulsion Systems

    NASA Astrophysics Data System (ADS)

    Rahola, Joaquim Clara; Weeks, Eric R.

    2009-03-01

    We study polydisperse decane-in-water emulsions at droplet volume fractions ranging from ? = 0.65 to ? = 0.9. At such concentrations emulsions are jammed and thus droplet rearrangements are limited. To induce droplet displacements, an oscillatory strain is applied. We use confocal microscopy to track the trajectories of the droplets in real time and space. Almost all the droplets move periodically, but due to the polydispersity many of them move non-affinely as they are pushed around by other droplets. In these glassy suspensions, the motions of nearby droplets are correlated within a characteristic distance. This length is independent of particle volume fraction while it exhibits an increasing trend with increasing strain amplitude. Moreover, despite the disordered structure of our system, droplets' motions are correlated over ranges longer than the average particle diameter.

  19. Chemical demulsification of petroleum emulsions using oil-soluable demulsifiers

    SciTech Connect

    Krawczyk, M.A.; Wasan, D.T.; Shetty, C.S. (Dept. of Chemical Engineering, Illinois Inst. of Technology, Chicago, IL (US))

    1991-02-01

    This paper investigates the factors affecting the coalescence and interfacial behavior of water- in-crude-oil emulsions in the presence of oil-soluble demulsifiers. The emulsion-breaking characteristics and interfacial properties of East Texas Crude and a model system were compared. The variation of interfacial tension with demulsifier concentration for the model system was ascertained by measuring the interfacial tensions between the oil and water phase. Interfacial activity, adsorption kinetics, and partitioning were shown to be the most important parameters governing demulsifier performance. A conceptual model of drop-drop coalescence process in demulsification was presented which indicates that the interfacial activity of the demulsifier must be high enough to suppress the interfacial tension gradient. This accelerates the rate of film drainage, thus promoting coalescence.

  20. Structure and Rheology of Stimuli-Responsive Pickering Emulsions

    NASA Astrophysics Data System (ADS)

    Ho, Dan; Sarangapani, Prasad; Zhu, Yingxi Elaine

    2009-03-01

    Self-assembly of micro-and nano-spheres and their stability at liquid-liquid interfaces are important due to their broad range of applications from emulsion polymerization to heavy oil transportation. In this work, we employ temperature-responsive poly(N-isopropyl acrylamide) (PNIPAM) microspheres to form Pickering emulsions and directly visualize the dynamics and rheology at the droplet interfaces in response to varied temperature using confocal laser scanning microscopy. Destabilization of the interface is observed as increasing temperature across the lower critical solution temperature (LCST) around 42-44 degree C for this system, where the coarsening at the oil-water interface occurs due to the shrinkage of PNIPAM particle size and results in the onset of coalescence of droplets.