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1

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

NASA Astrophysics Data System (ADS)

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.

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.

2

Central nucleus-nucleus interactions of an energy above 1 TeV/nucleon recorded in cosmic rays by stratospheric X-ray emulsion chambers.  

NASA Astrophysics Data System (ADS)

Studies characteristics of central nucleus-nucleus interactions of energy above 1 TeV/nucleon, recorded in cosmic rays by stratospheric X-ray emulsion chambers. Correlations in angular distribution of secondary charged particles are analyzed by the normalized factorial moments and Bose-Einstein correlations.

Apanasenko, A. V.; Goryachikh, A. A.; Zayarnaya, I. S.; Kvochkina, T. N.; Shalamova, S. Ya.

3

Large area emulsion chamber experiments for the Space Shuttle  

Microsoft Academic Search

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

T. A. Parnell

1985-01-01

4

Multifractal analysis of nucleus-nucleus interactions  

SciTech Connect

We have performed a multifractal ([ital G]-moment) analysis of 14.6--200 GeV/nucleon nucleus-nucleus and 200--800 GeV proton-nucleus interactions from KLM and Fermilab E-90 and E-508 emulsion data, including explicit corrections for the finite statistical sample. The corrected slopes of the [ital G] moments for protons, [sup 16]O, [sup 28]Si, and [sup 32]S nuclei show only slight evidence for departures from random behavior, while the normalized entropies appear to show a more consistent departure from randomness, particularly for protons. Given the size of the uncertainties, the results of the fractal analysis are not consistent either with results of intermittency analyses for nucleus-nucleus collisions or with the nonrandom behavior previously reported for leptonic and hadronic collisions. However, because of the effects of statistical noise, the fractal analysis is not as sensitive as the intermittency analysis for detecting nonrandom fluctuations.

Sengupta, K.; Cherry, M.L.; Jones, W.V.; Wefel, J.P. (Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)); Dabrowska, A.; Holynski, R.; Jurak, A.; Olszewski, A.; Szarska, M.; Trzupek, A.; Wilczynska, B.; Wilczynski, H.; Wolter, W.; Wosiek, B.; Wozniak, K. (Institute of Nuclear Physics, Kawiory 26 A, 30-055, Krakow (Poland)); Freier, P.S.; Waddington, C.J. (School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)); (KLM Collaboration)

1993-10-01

5

Single nucleon emission in relativistic nucleus-nucleus reactions  

Microsoft Academic Search

Significant discrepancies between theory and experiment have previously been noted for nucleon emission via electromagnetic processes in relativistic nucleus-nucleus collisions. The present work investigates the hypothesis that these discrepancies have arisen due to uncertainties about how to deduce the experimental electromagnetic cross section from the total measured cross section. An optical-model calculation of single neutron removal is added to electromagnetic

John W. Norbury; Lawrence W. Townsend

1992-01-01

6

Single nucleon emission in relativistic nucleus-nucleus reactions  

Microsoft Academic Search

Significant discrepancies between theory and experiment have previously been noted for nucleon emission via electromagnetic processes in relativistic nucleus-nucleus collisions. The present work investigates the hypothesis that these discrepancies have arisen due to uncertainties about how to deduce the experimental electromagnetic cross section from the total measured cross section. An optical-model calculation of single neutron removal is added to electromagnetic

John Norbury; Lawrence Townsend

1990-01-01

7

Nucleus-nucleus total reaction cross sections  

SciTech Connect

We compare sigma/sub R/(E) for nucleus-nucleus systems (obtained from existing direct measurements and derived from elastic scattering data) with nucleon-nucleon and nucleon-nucleus data. The energy dependence of sigma/sub R/(E) for nucleus-nucleus systems is found to be quite rapid; there appears to be no evidence for an energy independent, geometric sigma/sub R/. Simple parameter free microscopic calculations are able to quantitatively reproduce the data and thus, emphasize the dominance of nucleon-nucleon interactions in medium energy nucleus-nucleus collisions.

DeVries, R.M.; Peng, J.C.

1980-09-01

8

Nucleus-nucleus interaction between boosted nuclei  

SciTech Connect

The nucleus-nucleus interaction potential has been studied within the relativistic mean field theory. The systematics of the relativistic effects have been investigated by analyzing the relation between the potential and the bombarding energy as a function of the impact parameter. It is shown that the potential barriers are noticeably sensitive to the bombarding energy for a given impact parameter. At large bombarding energies, the slope at the potential edge decreases with the impact parameter. Comparisons with a nonrelativistic treatment shows that relativistic effects cannot be ignored at bombarding energies around and larger than 100 MeV/nucleon.

Long Wenhui [School of Nuclear Science and Technology, Lanzhou University, 730000 Lanzhou (China); Department of Physics, Texas AM University, Commerce, Texas 75429 (United States); Bertulani, Carlos A. [Department of Physics, Texas AM University, Commerce, Texas 75429 (United States)

2011-02-15

9

Nucleus-nucleus reactions above TeV/amu region  

SciTech Connect

Transverse moments of gamma rays and/or {pi}{sup 0} mesons produced in high energy ({approx gt}TeV/amu) cosmic ray nucleus-nucleus collisions have been measured with emulsion chambers. A group of events having large average transverse momenta, have been found, which exceed the apparent limiting behavior of increased with both increasing energy density and rapidity density. A set of heavy-ion collision data have been analysed to examine the photon to hadron production rate in the forward pseudorapidity region, in terms of number ratio, R{sub N} and of momentum flow ratio, R{sub M}. With some photon-rich events, the isospin structures along the pseudorapidity axis were examined. The results implies that in the event-by-event basis, the local isospin conservation does not apparently hold, however the global ratio, by estimating the total number of photons from the momentum distribution could restore the symmetries except for some special events. 34 refs., 12 figs., 2 tabs.

Not Available

1988-01-01

10

Onset of deconfinement in nucleus-nucleus collisions  

SciTech Connect

The energy dependence of hadron production in relativistic nucleus-nucleus collisions reveals anomalies-the kink, horn, and step. They were predicted as signals of the deconfinement phase transition and observed by the NA49 Collaboration in central PbPb collisions at the CERN SPS. This indicates the onset of the deconfinement in nucleus-nucleus collisions at about 30 A GeV.

Gazdzicki, M., E-mail: marek@mail.cern.ch [University of Frankfurt, Institut fuer Kernphysik (Germany); Gorenstein, M. I. [Bogolyubov Institute for Theoretical Physics (Ukraine); Seyboth, P. [Max-Planck-Institut fuer Physik (Germany)

2012-05-15

11

Higgs-boson production in nucleus-nucleus collisions.  

PubMed

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. PMID:10012777

Norbury, J W

1990-12-01

12

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

SciTech Connect

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.

NYSTRAND,J.

1998-09-10

13

Produced particle multiplicity dependence on centrality in nucleus - nucleus collisions  

Microsoft Academic Search

An equation is presented, which allows us to calculate the dependence of the multiplicity of the particles produced in nucleus - nucleus collisions, 0954-3899\\/22\\/10\\/010\\/img109, on an experimentally measured value 0954-3899\\/22\\/10\\/010\\/img110, which is strongly correlated to the impact parameter b. The equation combines data from a wide range of projectile masses (0954-3899\\/22\\/10\\/010\\/img111 - 197) over a large momentum region 0954-3899\\/22\\/10\\/010\\/img112. The

M. I. Adamovich; M. M. Aggarwal; Y. A. Alexandrov; R. Amirikas; N. P. Andreeva; Z. V. Anzon; R. Arora; F. A. Avetyan; S. K. Badyal; A. M. Bakich; E. S. Basova; I. K. Bazarov; K. B. Bhalla; A. Bhasin; V. S. Bhatia; V. G. Bogdanov; V. Bradnova; V. I. Bubnov; T. H. Burnett; X. Cai; D. A. Carshiev; I. Y. Chasnikov; L. P. Chernova; M. M. Chernyavsky; S. Dhamija; G. Z. Eligbaeva; L. E. Eremenko; A. S. Gaitinov; E. Ganssauge; S. Garpman; S. G. Gerassimov; C. Graf; J. G. Grote; K. G. Gulamov; S. K. Gupta; V. K. Gupta; U. Henjes; L. Just; S. Kachroo; G. S. Kalyachkina; E. K. Kanygina; M. Karabova; S. Kitroo; S. P. Kharlamov; A. D. Kovalenko; S. A. Krasnov; V. Kumar; V. G. Larionova; Y. D. Li; L. S. Liu; S. Lokanathan; J. J. Lord; N. S. Lukicheva; S. B. Luo; L. K. Mangotra; N. A. Marutyan; A. Y. Mashkov; N. V. Maslennikova; I. S. Mittra; S. Mookerjee; S. Z. Nasyrov; V. S. Navotny; J. Nystrand; M. Ochs; G. I. Orlova; I. Otterlund; L. S. Peak; N. G. Peresadko; N. V. Petrov; V. A. Plyushchev; V. V. Rusokova; W. Y. Qian; Y. M. Quin; R. Raniwala; N. K. Rao; M. Röper; N. Saidkhanov; N. A. Samanova; L. G. Sarkisova; V. R. Sarkisyan; G. S. Shabratova; A. M. Seitimbetov; C. I. Shakhova; S. N. Shpilev; D. Skelding; K. Söderström; Z. I. Solovjeva; E. Stenlund; L. N. Svechnikova; T. Svensson; A. M. Tawfik; M. Tothova; M. I. Tretyakova; T. P. Trofimova; U. I. Tuleeva; B. P. Tursunov; S. Vokal; J. Vrlakova; H. Q. Wang; Z. Q. Weng; R. J. Wilkes; Y. L. Xia; C. B. Yang; D. H. Zhang; P. Y. Zheng; S. I. Zhokhova; D. C. Zhou

1996-01-01

14

Toward a systematic nucleus-nucleus potential for peripheral collisions  

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

15

Dynamical nucleus-nucleus potential at short distances  

SciTech Connect

The dynamical nucleus-nucleus potentials for fusion reactions {sup 40}Ca+{sup 40}Ca, {sup 48}Ca+{sup 208}Pb, and {sup 126}Sn+{sup 130}Te are studied with the improved quantum molecular dynamics model together with the extended Thomas-Fermi approximation for the kinetic energies of nuclei. The obtained fusion barrier for {sup 40}Ca+{sup 40}Ca is in good agreement with the extracted fusion barrier from the measured fusion excitation function, and the depths of the fusion pockets are close to the results of time-dependent Hartree-Fock calculations. The energy dependence of the fusion barrier is also investigated. The fusion pocket becomes shallow for a heavy fusion system and almost disappears for heavy nearly symmetric systems, and the obtained potential at short distances is higher than the adiabatic potential.

Jiang Yongying; Wang Ning [Department of Physics, Guangxi Normal University, Guilin 541004 (China); Li Zhuxia [China Institute of Atomic Energy, Beijing 102413 (China); Scheid, Werner [Institute for Theoretical Physics, Justus-Liebig-University, D-35392 Giessen (Germany)

2010-04-15

16

Genetic Programing Modeling for Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

High Energy Physics (HEP), due to the vast and complex data expected from current and future experiments, is in need of powerful and efficient techniques for various analysis tasks. Genetic Programing (GP) is a powerful technique that can be used such complex tasks. In this paper, Genetic programing is used for modeling the functions that describe the pseudo-rapidity distribution of the shower particles for 12C, 16O, 28Si and 32S on nuclear emulsion and also to predict the distributions that are not present in the training set and matched them effectively. The proposed method shows a better fitting with experimental data. The GP prediction results prove a strong presence modeling in heavy ion collisions.

El-Dahshan, El-Sayed; Radi, Amr; El-Bakry, Mahmoud Y.

17

Rheology and microstructure of magmatic emulsions - Theory and experiments  

NASA Astrophysics Data System (ADS)

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.

Stein, Daniel J.; Spera, Frank J.

1992-01-01

18

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

SciTech Connect

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.

Chessin, S.A.

1983-05-01

19

Nucleus-nucleus interaction above several hundred GeV/n  

NASA Astrophysics Data System (ADS)

The Japanese-American Cooperative Emulsion Experiment (JACEE) have been investigating high energy nuclear interactions of cosmic ray nuclei by means of balloon-borne emulsion chamber. Current exposure parameters are listed. Analysis of the last two experiments (JACEE4 and JACEE5) are still in progress. A result of semi-inclusive analysis of a sample set of central collision events is presented here, concerning multiplicity, rapidity fluctuation for extremely high multiplicity events and correlation between transverse momentum and estimated energy density.

Burnett, T. H.; Dake, S.; Fuki, M.; Gregory, J. C.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W. V.; Jurak, A.; Lord, J. J.

1985-08-01

20

The classical field created in early stages of high energy nucleus-nucleus collisions  

NASA Astrophysics Data System (ADS)

We show that a special choice of light-cone gauge can greatly simplify the calculation of the classical color field created in the initial stages of nucleus-nucleus collisions. Within this gauge, we can in particular construct explicitly the conserved color current and calculate exactly the gauge field immediately after the collision. This field is used as a boundary condition in an iterative solution of the Yang-Mills equations in the forward light-cone. In leading order, which corresponds to a linearization of the Yang-Mills equation in the forward light-cone, we obtain a simple formula for the spectrum of gluons produced in nucleus-nucleus collisions. This formula reproduces exactly the known formula for proton-nucleus collisions, where k-factorization is recovered, while the latter property apparently breaks down in the case of nucleus-nucleus collisions.

Blaizot, Jean-Paul; Mehtar-Tani, Yacine

2009-02-01

21

Toward describing one-nucleon exchange in nucleus-nucleus scattering  

SciTech Connect

The effect of one-nucleon exchanges on the potential of nucleus-nucleus interaction is considered on the basis of the resonating-group method. Corrections to the folding-model potential are obtained in the semiclassical approximation. Neutron scattering on {sup 4}He nuclei is considered as a model example.

Fadeev, S. N., E-mail: fsn3@yandex.ru; Gridnev, K. A., E-mail: kgridnev@yahoo.co [St. Petersburg State University (Russian Federation)

2010-12-15

22

Gribov?s inelastic screening in high energy nucleus-nucleus interaction  

NASA Astrophysics Data System (ADS)

We show that at LHC energies an accounting for the Gribov's screenings in the framework of the quasi-eikonal approach generalized for nucleus-nucleus interactions leads to a significant (˜19%) decrease in the number of participating nucleons and intra-nuclear collision multiplicity for Pb+Pb interactions. Predictions for other energies and interactions are given also.

Uzhinsky, V.; Galoyan, A.

2013-04-01

23

Estudio fenomenologico de las colisiones nucleo-nucleo. (Phenomenological study of nucleus-nucleus collision).  

National Technical Information Service (NTIS)

Several aspects of high energy nucleus-nucleus collisions are analyzed in the framework of Dual Parton Model and Glauber-Gribov formalism. First of all the leading baryon spectra are calculated and an extensive study of nuclear stopping power are presente...

J. Casado Alvarez

1988-01-01

24

Toward describing one-nucleon exchange in nucleus-nucleus scattering  

Microsoft Academic Search

The effect of one-nucleon exchanges on the potential of nucleus-nucleus interaction is considered on the basis of the resonating-group\\u000a method. Corrections to the folding-model potential are obtained in the semiclassical approximation. Neutron scattering on\\u000a 4He nuclei is considered as a model example.

S. N. Fadeev; K. A. Gridnev

2010-01-01

25

Toward describing one-nucleon exchange in nucleus-nucleus scattering  

Microsoft Academic Search

The effect of one-nucleon exchanges on the potential of nucleus-nucleus interaction is considered on the basis of the resonating-group method. Corrections to the folding-model potential are obtained in the semiclassical approximation. Neutron scattering on 4He nuclei is considered as a model example.

S. N. Fadeev; K. A. Gridnev

2010-01-01

26

One-nucleon exchange and the effective local potential in nucleus-nucleus scattering  

Microsoft Academic Search

The influence of one-nucleon exchange on the local nucleus-nucleus potential is investigated using the resonating group method.\\u000a Neutron scattering on 4He and 16O nuclei is examined in detail. The results are compared to microscopic calculations.

S. N. Fadeev; K. A. Gridnev

2011-01-01

27

Nucleon Molecular Orbitals and the Transition Mechanism Between Molecular Orbitals in Nucleus-Nucleus Collisions.  

National Technical Information Service (NTIS)

The molecular orbitals of the nucleon(s) in nucleus-nucleus collisions are dynamically defined as a linear combination of nucleon single-particle orbits (LCNO) in a rotating frame by using the coupled-reaction-channel (CRC) theory. Nucleon molecular orbit...

B. Imanishi S. Misono W. von Oertzen H. Voit

1988-01-01

28

Nucleus-nucleus collisions and the nuclear equation of state  

SciTech Connect

Activities during the period of support have been centered around (1) the analysis of existing experimental data from the Bevalac streamer chamber and from the Kent State neutron flow experiment 848H; (2) work at the interface between theory and experiment, including transport model comparisons with the above data and with published results from other experiments, a new model to probe the possible use of spectator recoil to measure properties of the equation of state, and new methodologies for study of flow and HBT correlations, and (3) development of future Bevalac experiments, with particular emphasis on the EOS TPC.

Keane, D.

1991-01-01

29

Calorimetry applied to nucleus-nucleus collisions at ultrarelativistic energies  

SciTech Connect

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.

Plasil, F.

1988-01-01

30

Nucleus-nucleus scattering structure using the first order optical potential  

SciTech Connect

First order optical potential is used to calculate the total cross section, differential cross section, and absorption-cross section for nucleus-nucleus scattering. The results are compared to the available Eikonal model and the experimental data in the energy range 100-1000 MeV for several nuclei. The differential and absorption cross sections are calculated using partial wave expansion. The partial waves are obtained by solving the Lippmann-Scwinger equation in momentum space.

Dubey, R.R.; Khandelwal, G.S. [and others

1993-10-01

31

Double-? hypernuclei observed in a hybrid emulsion experiment  

NASA Astrophysics Data System (ADS)

A hybrid experiment with nuclear emulsion and scintillating-fiber detectors (KEK-E373) has been performed to search for double-strangeness systems. Among about 103 events of ?- hyperons captured at rest by emulsion nuclei, we have observed four events which clearly show the topology of cascade weak decays of double-? hypernuclei including the “Nagara” event. Regarding the Nagara event, values of the two-? binding energy (B??) and the ?-? interaction energy (?B??) of ??6He have been revised to 6.91 ± 0.16 and 0.67 ± 0.17 MeV, respectively, due to the recent change of the ?- mass value (Particle Data Group). For another three events, we have determined possible species of double-? hypernuclei together with their binding energies.

Ahn, J. K.; Akikawa, H.; Aoki, S.; Arai, K.; Bahk, S. Y.; Baik, K. M.; Bassalleck, B.; Chung, J. H.; Chung, M. S.; Davis, D. H.; Fukuda, T.; Hoshino, K.; Ichikawa, A.; Ieiri, M.; Imai, K.; Itonaga, K.; Iwata, Y. H.; Iwata, Y. S.; Kanda, H.; Kaneko, M.; Kawai, T.; Kawasaki, M.; Kim, C. O.; Kim, J. Y.; Kim, S. H.; Kim, S. J.; Kondo, Y.; Kouketsu, T.; Kyaw, H. N.; Lee, Y. L.; McNabb, J. W. C.; Min, A. A.; Mitsuhara, M.; Miwa, K.; Nakazawa, K.; Nagase, Y.; Nagoshi, C.; Nakanishi, Y.; Noumi, H.; Ogawa, S.; Okabe, H.; Oyama, K.; Park, B. D.; Park, H. M.; Park, I. G.; Parker, J.; Ra, Y. S.; Rhee, J. T.; Rusek, A.; Sawa, A.; Shibuya, H.; Sim, K. S.; Saha, P. K.; Seki, D.; Sekimoto, M.; Song, J. S.; Takahashi, H.; Takahashi, T.; Takeutchi, F.; Tanaka, H.; Tanida, K.; Tint, K. T.; Tojo, J.; Torii, H.; Torikai, S.; Tovee, D. N.; Tsunemi, T.; Ukai, M.; Ushida, N.; Wint, T.; Yamamoto, K.; Yasuda, N.; Yang, J. T.; Yoon, C. J.; Yoon, C. S.; Yosoi, M.; Yoshida, T.; Zhu, L.

2013-07-01

32

A Relativistic Multiple Scattering Theory for Nucleus-Nucleus Collisions with Delta Resonance Coupling  

NASA Astrophysics Data System (ADS)

Non-relativistic multiple scattering theories (NRMST) are formulated by separating the unperturbed Hamiltonian from the interaction and writing the Lippmann-Schwinger equation as an infinite series in the multiple sums of pseudo two-body operators, known as the Watson tau-operators. The advantage of using the multiple scattering theory (MST) is that the pseudo two-body operators are often well approximated by free two-body nucleon-nucleon operators, which are obtained from parameterizations of experimental data. Relativistic theories are needed to properly describe the production of new particles, such as pions, from nucleus-nucleus collisions. Relativistic multiple scattering theories (RMST) have been developed for nucleon-nucleus scattering; however, no RMST for nucleus-nucleus scattering has yet been derived.footnotetextMaung K M, Norbury J W, and Coleman T 2007 J. Phys. G 34 1861. The purpose of this research is to derive an RMST for nucleus-nucleus scattering and to include delta degrees of freedom in the interaction, the minimum requirement for pion production.

Werneth, Charles; Maung Maung, Khin; Norbury, John

2012-10-01

33

Inelasticity of nucleus-nucleus collisions and composition of high-energy cosmic rays  

SciTech Connect

Current experiments to determine the chemical composition and energy spectra of primary-cosmic-ray nuclei around 10/sup 14/ eV maximize collecting power by using thin calorimeters of large area that measure primarily the electromagnetic fraction of the energy released when the nucleus interacts. Estimates of this fraction are model-dependent and differ by nearly a factor of 2 for a range of reasonable models. We discuss the consequences of this for composition studies using emulsion chambers.

Gaisser, T.K.; Stanev, T.

1983-08-01

34

J/? suppression from hadron-nucleus to nucleus-nucleus collisions  

NASA Astrophysics Data System (ADS)

We explore the combined role of inelastic final-state scattering with nucleons and comoving secondary particles in the suppression of J/? production for hadron-nucleus and nucleus-nucleus collisions, as functions of target mass, beam energy, and transverse energy. Our interpretation of recent data suggests that nuclear scattering dominates the suppression for ? + A collisions at 125 GeV while a comparable contribution from scattering in a dense comover gas emerges for O + U and S + U at 200 AGeV. Formerly: Physics Department, State University of New York, Stony Brook, NY 11794, USA. Present address: Lawrence Livermore Laboratory, PO Box 808, Livermore, CA 94550, USA.

Gavin, S.; Vogt, R.

1990-11-01

35

Subthreshold pion production from nucleus-nucleus collisions around 100 MeV/nucleon  

NASA Astrophysics Data System (ADS)

Several global variables were tested with the aim to determine the impact parameter in nucleus-nucleus collisions producing pions at incident energies around 100 MeV/nucleon. The experimental set-up includes the MEDEA multidetector, part of which is used as a ? 0 spectrometer, and an additional hodoscope of plastic scintillators to cover very forward angles. A statistical model was used to generate both inclusive and pion-triggered events. Selection of well measured events was made through the measured total parallel momentum. Among the different global variables which were tested, the average parallel velocity was seen to give the best correlation with the impact parameter.

Badalá, A.; Barbera, R.; Palmeri, A.; Pappalardo, G. S.; Riggi, F.; Russo, A. C.

1993-12-01

36

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

SciTech Connect

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.

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

2009-03-04

37

Jet Tomography of High-Energy Nucleus-Nucleus Collisions at Next-to-Leading Order  

SciTech Connect

We demonstrate that jet observables are highly sensitive to the characteristics of the vacuum and the in-medium QCD parton showers and propose techniques that exploit this sensitivity to constrain the mechanism of quark and gluon energy loss in strongly interacting plasmas. As a first example, we calculate the inclusive jet cross section in high-energy nucleus-nucleus collisions to O({alpha}{sub s}{sup 3}). Theoretical predictions for the medium-induced jet broadening and the suppression of the jet production rate due to cold and hot nuclear matter effects in Au+Au and Cu+Cu reactions at RHIC are presented.

Vitev, Ivan [Theoretical Division, Los Alamos National Laboratory, MS B238, Los Alamos, New Mexico 87545 (United States); Zhang Benwei [Key Laboratory of Quark Lepton Physics, Hua-Zhong Normal University, Ministry of Education (China)

2010-04-02

38

Jet tomography of high-energy nucleus-nucleus collisions at next-to-leading order  

SciTech Connect

We demonstrate that jet observables are highly sensitive to the characteristics of the vacuum and the in-medium QCD parton showers and propose techniques that exploit this sensitivity to constrain the mechanism of quark and gluon energy loss in strongly-interacting plasmas. As a first example, we calculate the inclusive jet cross section in high-energy nucleus-nucleus collisions to {Omicron}({alpha}{sub s}{sup 3}). Theoretical predictions for the medium-induced jet broadening and the suppression of the jet production rate due to cold and hot nuclear matter effects in Au+Au and Cu+Cu reactions at RHIC are presented.

Vitev, Ivan [Los Alamos National Laboratory; Zhang, Ben - Wei [Los Alamos National Laboratory

2009-01-01

39

High energy factorization in nucleus-nucleus collisions. II. Multigluon correlations  

SciTech Connect

We extend previous results from the preceding paper on factorization in high energy nucleus-nucleus collisions by computing the inclusive multigluon spectrum to next-to-leading order. The factorization formula is strictly valid for multigluon emission in a slice of rapidity of width {delta}Y{<=}{alpha}{sub s}{sup -1}. Our results shows that often neglected disconnected graphs dominate the inclusive multigluon spectrum, and are crucial in order to achieve factorization for this quantity. These results provide a dynamical framework for the Glasma flux tube picture of the striking ''ridge''-like correlation seen in heavy ion collisions.

Gelis, Francois [Theory Division, PH-TH, Case C01600, CERN, CH-1211, Geneva 23 (Switzerland); Lappi, Tuomas [Institut de Physique Theorique (URA 2306 du CNRS) CEA/DSM/Saclay, Batiment 774 91191, Gif-sur-Yvette Cedex (France); Venugopalan, Raju [Physics Department, Brookhaven National Laboratory Upton, New York 11973 (United States)

2008-09-01

40

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

NASA Astrophysics Data System (ADS)

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 ?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.

Moreira, B. D.; Gonçalves, V. P.; De Santana Amaral, J. T.

2013-03-01

41

Experiments and network model of flow of oil-water emulsion in porous media  

NASA Astrophysics Data System (ADS)

Transport of emulsions in porous media is relevant to several subsurface applications. Many enhanced oil recovery (EOR) processes lead to emulsion formation and as a result conformance originating in the flow of a dispersed phase may arise. In some EOR processes, emulsion is injected directly as a mobility control agent. Modeling the flow of emulsion in porous media is extremely challenging due to the complex nature of the associated flows and numerous interfaces. The descriptions based on effective viscosity are not valid when the drop size is of the same order of magnitude as the pore-throat characteristic length scale. An accurate model of emulsion flow through porous media should describe this local change in mobility. The available filtration models do not take into account the variation of the straining and capturing rates with the local capillary number. In this work, we present experiments of emulsion flow through sandstone cores of different permeability and a first step on a capillary network model that uses experimentally determined pore-level constitutive relationships between flow rate and pressure drop in constricted capillaries to obtain representative macroscopic flow behavior emerging from microscopic emulsion flow at the pore level. A parametric analysis is conducted to study the effect of the permeability and dispersed phase droplet size on the flow response to emulsion flooding in porous media. The network model predictions qualitatively describe the oil-water emulsion flow behavior observed in the experiments.

Romero, Mao Illich; Carvalho, Marcio S.; Alvarado, Vladimir

2011-10-01

42

Experiments and network model of flow of oil-water emulsion in porous media.  

PubMed

Transport of emulsions in porous media is relevant to several subsurface applications. Many enhanced oil recovery (EOR) processes lead to emulsion formation and as a result conformance originating in the flow of a dispersed phase may arise. In some EOR processes, emulsion is injected directly as a mobility control agent. Modeling the flow of emulsion in porous media is extremely challenging due to the complex nature of the associated flows and numerous interfaces. The descriptions based on effective viscosity are not valid when the drop size is of the same order of magnitude as the pore-throat characteristic length scale. An accurate model of emulsion flow through porous media should describe this local change in mobility. The available filtration models do not take into account the variation of the straining and capturing rates with the local capillary number. In this work, we present experiments of emulsion flow through sandstone cores of different permeability and a first step on a capillary network model that uses experimentally determined pore-level constitutive relationships between flow rate and pressure drop in constricted capillaries to obtain representative macroscopic flow behavior emerging from microscopic emulsion flow at the pore level. A parametric analysis is conducted to study the effect of the permeability and dispersed phase droplet size on the flow response to emulsion flooding in porous media. The network model predictions qualitatively describe the oil-water emulsion flow behavior observed in the experiments. PMID:22181259

Romero, Mao Illich; Carvalho, Marcio S; Alvarado, Vladimir

2011-10-10

43

Siegert approach within a microscopic description of nucleus-nucleus bremsstrahlung  

NASA Astrophysics Data System (ADS)

Previous studies of nucleus-nucleus bremsstrahlung within the microscopic cluster model made use of a simplified current version of the electric transition operators, neglecting the meson exchange currents. The present microscopic cluster model relies on operators based on the charge density derived from an extension of the Siegert theorem valid for arbitrary photon energy. A part of the meson exchange current effects is then implicitly included in this approach. Divergence problems in matrix elements are avoided. The model is applied to the ?+? system at low photon energy for which experimental data are available. In particular, good agreement is obtained with data about on- and off-resonance 4+?2+ transitions. The differences between the charge and current approaches are discussed on this example.

Dohet-Eraly, J.; Baye, D.

2013-08-01

44

Nuclear radii calculations in various theoretical approaches for nucleus-nucleus interactions  

SciTech Connect

The information about sizes and nuclear density distributions in unstable (radioactive) nuclei is usually extracted from the data on interaction of radioactive nuclear beams with a nuclear target. We show that in the case of nucleus-nucleus collisions the values of the parameters depend somewhat strongly on the considered theoretical approach and on the assumption about the parametrization of the nuclear density distribution. The obtained values of root-mean-square radii (R{sub rms}) for stable nuclei with atomic weights A=12-40 vary by approximately 0.1 fm when calculated in the optical approximation, in the rigid target approximation, and using the exact expression of the Glauber theory. We present several examples of R{sub rms} radii calculations using these three theoretical approaches and compare these results with the data obtained from electron-nucleus scattering.

Merino, C.; Novikov, I. S.; Shabelski, Yu. [Departamento de Fisica de Particulas, Facultade de Fisica, and Instituto Galego de Fisica de Altas Enerxias (IFGAE), Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Galiza (Spain); Department of Physics and Astronomy, Western Kentucky University, Bowling Green, Kentucky 42101-1077 (United States); Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188350 (Russian Federation)

2009-12-15

45

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

SciTech Connect

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.

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

1986-01-01

46

Nuclear radii calculations in various theoretical approaches for nucleus-nucleus interactions  

NASA Astrophysics Data System (ADS)

The information about sizes and nuclear density distributions in unstable (radioactive) nuclei is usually extracted from the data on interaction of radioactive nuclear beams with a nuclear target. We show that in the case of nucleus-nucleus collisions the values of the parameters depend somewhat strongly on the considered theoretical approach and on the assumption about the parametrization of the nuclear density distribution. The obtained values of root-mean-square radii (Rrms) for stable nuclei with atomic weights A=12-40 vary by approximately 0.1 fm when calculated in the optical approximation, in the rigid target approximation, and using the exact expression of the Glauber theory. We present several examples of Rrms radii calculations using these three theoretical approaches and compare these results with the data obtained from electron-nucleus scattering.

Merino, C.; Novikov, I. S.; Shabelski, Yu.

2009-12-01

47

Attenuation of Sound in Suspensions and Emulsions: Theory and Experiments.  

National Technical Information Service (NTIS)

The absorption of sound in emulsions and suspensions is due to viscous and thermal transport processes occurring at the interface of the nonhomogeneities, as well as to the intrinsic absorption in the materials comprising the system. A complete descriptio...

J. R. Allegra S. A. Hawley

1971-01-01

48

Study of the effects induced by lead on the emulsion films of the OPERA experiment  

NASA Astrophysics Data System (ADS)

The OPERA neutrino oscillation experiment is based on the use of the Emulsion Cloud Chamber (ECC). In the OPERA ECC, nuclear emulsion films acting as very high precision tracking detectors are interleaved with lead plates providing a massive target for neutrino interactions. We report on studies related to the effects occurring from the contact between emulsion and lead. A low radioactivity lead is required in order to minimize the number of background tracks in emulsions and to achieve the required performance in the reconstruction of neutrino events. It was observed that adding other chemical elements to the lead, in order to improve the mechanical properties, may significantly increase the level of radioactivity on the emulsions. A detailed study was made in order to choose a lead alloy with good mechanical properties and an appropriate packing technique so as to have a low enough effective radioactivity.

Anokhina, A.; Aoki, S.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bay, F.; Bergnoli, A.; Bersani Greggio, F.; 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.; 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.; Dulach, B.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, A.; Esposito, L. S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Franceschi, A.; Fukuda, T.; Fukushima, C.; Galkin, V. I.; Galkin, V. A.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Golubkov, D.; Gornoushkin, 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.; Kimura, M.; 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.; Manzoor, S.; Marotta, A.; Marteau, J.; Matsuoka, H.; Mauri, N.; Meisel, F.; Meregaglia, A.; Messina, M.; Migliozzi, P.; 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.; 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, Y.; Sato, O.; 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.; Tioukov, V.; Togo, V.; Tolun, P.; Tsarev, V.; Tufanli, S.; Ushida, N.; Valieri, C.; 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, A.; Zimmermann, R.

2008-07-01

49

Observation of nucleus-nucleus interactions at the energy more than 10 GeV/nucleon  

NASA Astrophysics Data System (ADS)

An emulsion chamber with pure metal target plates (copper and lead) in the producer layers is exposed to high-energy cosmic heavy nuclei in a balloon experiment. The charge numbers of the incident heavy nuclei are determined by using the sensitive plastic track detector. The energies of the primary heavy nuclei are estimated to be more than 5 GeV/nucleon, with the value of the vertical geomagnetic cut-off rigidity of the primary particles considered to be 4.5 GeV/nucleon. The nuclear interactions between the heavy nuclei and the pure metal plates are picked up by tracing the heavy tracks down to their vertices of the nuclear interactions.

Fumuro, F.; Ihara, R.; Ohta, I.; Sato, Y.; Tezuka, I.; Tasaka, S.; Sugimoto, H.

50

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

SciTech Connect

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.

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

51

Nucleus-nucleus bremsstrahlung from scattering angle selected Cl-Sn collisions  

NASA Astrophysics Data System (ADS)

Continuum X-rays above the K lines of Sn were measured at 90° and 0° angle relative to the incident beam direction in coincidence with Cl projectiles scattered at very large laboratory angles between 8° and 164°. By varying the isotope mass of the projectile ions (35Cl and 37Cl) and of the target atoms (112Sn and 118Sn) the radiation at scattering angles > 10° 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° relative to the beam direction can be reasonably well described by a quantum mechanical calculation of nucleus-nucleus bremsstrahlung by Reinhardt et al. [7] which includes the interference between dipole and quadrupole radiation amplitude. Present address: Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831. Research sponsored by the US Department of Energy, Division of Chemical Sciences under Contract No. DE-AC05-840R21400 with Martin Marietta Energy Systems, Inc.

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

1987-07-01

52

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

Microsoft Academic Search

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,

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

53

Density dependent interactions and the consistency of folding estimates of nucleon-nucleus and nucleus-nucleus potentials  

Microsoft Academic Search

It is shown that density dependence in the interaction does effect the consistency of the results obtained in folding calculations of nucleon-nucleus and nucleus-nucleus potentials. A modified density dependent version of the new G matrix interaction of Bertsch et al. gives reasonable results for both. Present address: Bettis Atomic Power Laboratory, Westinghouse Electric Corporation, P.O. Box 79, West Mifflin, Pennsylvania

F. Petrovich; J. J. Bevelacqua

1977-01-01

54

Global characteristics of oxygen and sulfur interactions in emulsion at 200 GeV/nucleon  

SciTech Connect

Oxygen and sulfur nuclei with energies of 200 GeV/nucleon from CERN (experiment EMU07) interacted in nuclear emulsions, which were scanned with minimum bias criteria so that essentially all the interactions are detected. Approximately 1000 interactions of each projectile have been analyzed. Results on the multiplicity distributions of produced particles and their pseudorapidity distributions are presented. The mean number of intranuclear collisions occurring in each interaction, calculated from a superposition model, provides a useful parameter to organize the data. No significant deviations are found, even at these energies, from models such as the Venus'' model, of the nucleus---nucleus interactions as being the superposition of individual nucleon-nucleon collisions.

Dabrowska, A.; Holynski, R.; Jurak, A.; Olszewski, A.; Szarska, M.; Trzupek, A.; Wilczynska, B.; Wilczynski, H.; Wolter, W.; Wosiek, B.; Wozniak, K. (Institute of Nuclear Physics, Kawiory 26A, 30-055 Krakow (Poland)); Cherry, M.L.; Jones, W.V.; Sengupta, K.; Wefel, J.P. (Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)); Freier, P.S.; Waddington, C.J. (School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)); The KLM Collaboration

1993-06-15

55

Enhanced characterization of oilfield emulsions via NMR diffusion and transverse relaxation experiments.  

PubMed

The procedure proposed by Packer and Rees (J. Colloid Interface Sci. 40 (1972) 206) to interpret pulsed field gradient spin-echo (PGSE) experiments on emulsions is commonly used to resolve for the distribution of droplet sizes via nuclear magnetic resonance (NMR). Nevertheless, such procedure is based on several assumptions that may restrict its applicability in many practical cases. Among such constrains, (a) the amplitude of the spin-echo (signal) must be influenced solely by the drop phase, and not by the continuous phase; and (b) the shape of the drop size distribution must be assumed a priori. This article discusses new theory to interpret results from PGSE experiments and a novel procedure that couples diffusion measurements (PGSE) with transverse relaxation rate experiments (the so-called CPMG sequence) to overcome the above limitations. Results from experiments on emulsions of water dispersed in several crude oils are reported to demonstrate that the combined CPMG-PGSE method renders drop size distributions with arbitrary shape, the water/oil ratio of the emulsion and the rate of decay of magnetization at the interfaces, i.e. the surface relaxivity. It is also shown that the procedure allows screening if the dispersion is oil-in-water (o/w) or water-in-oil (w/o) in a straightforward manner and that it is suitable to evaluate stability of emulsions. PMID:12969643

Peña, Alejandro A; Hirasaki, George J

2003-09-18

56

Artificial Neural Network and Genetic Algorithm Hybrid Technique for Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

Selecting the optimal topology of a neural network for a particular application is a difficult task. Genetic Algorithm (GA) has been used to find the optimal neural network (NN) solution (i.e., hybrid technique) to calculate the pseudo-rapidity distribution of the shower particles for C12, O16, Si28, and S32 on nuclear emulsion. An efficient NN has been designed by GA to predict the distributions that are not present in the training set and matched them effectively. The proposed method shows a better fitting with experimental data. The hybrid technique GA-ANN simulation results prove a strong presence modeling in heavy ion collisions.

El-Dahshan, E.; Radi, A.; El-Bakry, M. Y.

57

Extremely high multiplicities in high-energy nucleus-nucleus collisions  

NASA Astrophysics Data System (ADS)

Two unusually-high-multiplicity interactions of high-energy heavy nuclei were observed in a balloon-borne emulsion chamber: an Si(+)AgBr event (4 TeV/nucleon) and a Ca(+)C event (100 TeV/nucleon), with 1015 and 760 charged particles, respectively. The multiplicities and rapidity distributions favor the multichain model but not the wounded-nucleon superposition model. The high average transverse momentum (550-700 MeV/c) and the rapid fluctuations of the events are not readily understood in terms of any superposition models.

Burnett, T. H.; Dake, S.; Fuki, M.; Gregory, J. C.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W. V.; Jurak, A.; Lord, J. J.

1983-06-01

58

Multiplicities and angular distributions of nucleus-nucleus interactions at SPS energies: Protons to lead  

SciTech Connect

Charged particle multiplicities from high multiplicity interactions of 158 GeV/n Pb ions on Pb targets were measured in nuclear emulsion chambers. These measurements are compared to measurements of central interactions of 200 GeV/n p, O, and S beams on silver or bromine and to simulations from the FRITIOF 7.02 and Venus 4.12 Monte Carlo event generators. Multiplicities in the central region are significantly lower than either simulation predicts. Venus, the only one of the two which attempts to incorporate reinteraction phenomena, predicts a significant narrowing of the pseudorapidity distribution for the highest multiplicity events, which is not observed in the data. However, we do find evidence for unexpectedly high spectator proton transverse momenta.

Cherry, M. L.; Deines-Jones, P.; Dugas, J.; Jones, W. V.; Nilsen, B. S.; Wefel, J. P. [Louisiana State University, Baton Rouge, Louisiana (United States); Dabrowska, A.; Holynski, R.; Kudzia, D.; Olszewski, A.; Szarska, M.; Trzupek, A.; Wilczynska, B.; Wilczynski, H.; Wolter, W.; Wosiek, B.; Wozniak, K. [Institute for Nuclear Physics, Krakow (Poland); Waddington, C. J. [University of Minnesota, Minneapolis, Minnesota (United States)

1997-05-20

59

Multiplicities and angular distributions of nucleus-nucleus interactions at SPS energies: Protons to lead  

SciTech Connect

Charged particle multiplicities from high multiplicity interactions of 158 GeV/n Pb ions on Pb targets were measured in nuclear emulsion chambers. These measurements are compared to measurements of central interactions of 200 GeV/n p, O, and S beams on silver or bromine and to simulations from the FRITIOF 7.02 and Venus 4.12 Monte Carlo event generators. Multiplicities in the central region are significantly lower than either simulation predicts. Venus, the only one of the two which attempts to incorporate reinteraction phenomena, predicts a significant narrowing of the pseudorapidity distribution for the highest multiplicity events, which is not observed in the data. However, we do find evidence for unexpectedly high spectator proton transverse momenta. {copyright} {ital 1997 American Institute of Physics.}

KLM Collaboration

1997-05-01

60

Longitudinal boost invariance of the charge balance function in hadron-hadron and nucleus-nucleus collisions  

SciTech Connect

Using Monte Carlo generators of the PYTHIA model for hadron-hadron collisions and a multiphase transport (AMPT) model for nucleus-nucleus collisions, the longitudinal boost invariance of charge balance function and its transverse-momentum dependence are carefully studied. It shows that the charge balance function is boost invariant in both p+p and Au+Au collisions in these two models, consistent with experimental data. The balance function properly scaled by the width of the pseudorapidity window is independent of the position or the size of the window and is corresponding to the balance function of the whole pseudorapidity range. This longitudinal property of balance function also holds for particles in small transverse-momentum ranges in the PYTHIA and the AMPT default models, but is violated in the AMPT with string melting. The physical origin of the results is discussed.

Li Na; Li Zhiming; Wu Yuanfang [Key Laboratory of Quark and Lepton Physics, Ministry of Education Institute of Particle Physics, Huazhong Normal University, Wuhan 430079 (China)

2009-12-15

61

{Psi}{sup {prime}}/{Psi} Ratio in Nucleus-Nucleus Collisions: A Measure for the Chiral Symmetry Restoration Temperature?  

SciTech Connect

We argue that a decrease of the chiral scalar meson mass is responsible for recreation of {Psi}{sup {prime}} from J/{Psi} in ultrarelativistic nucleus-nucleus collisions. This causes the charmonium yields to freeze out at temperatures close to the chiral symmetry restoration temperature T{sub c} . As a result the ratio {Psi}{sup {prime}}/{Psi} may serve as a thermometer for T{sub c} itself. Results in a detailed reaction model support the conjecture. They show good agreement with recent data of NA38 and NA50 for J/{Psi} and {Psi}{sup {prime}} production in S on U and Pb on Pb collisions. {copyright} {ital 1997} {ital The American Physical Society}

Sorge, H.; Shuryak, E.; Zahed, I. [Physics Department, State University of New York at Stony Brook, Stony Brook, New York 11794-3800 (United States)

1997-10-01

62

Color-neutral heavy particle production in nucleus-nucleus collisions in the quasi-classical approximation  

NASA Astrophysics Data System (ADS)

We use a diagrammatic approach to study color-neutral heavy particle production in nucleus-nucleus collisions in a quasi-classical approximation without small-x evolution. In order to treat the two nuclei symmetrically, we use the Coulomb gauge which gives the appropriate light cone gauge for each nucleus. The resulting cross section is factorized into a product of two Weizsäcker-Williams gluon distributions of the two nuclei when the transverse momentum of the produced scalar particle is around the saturation momentum. We confirm our results in covariant gauge where the transverse momentum broadening of hard gluons can be described as a diffusion process. The transverse momentum factorization manifests itself in light cone gauge but not so clearly in covariant gauge.

Liou, Tseh

2013-01-01

63

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

NASA Astrophysics Data System (ADS)

We present a new global optical potential (GOP) for nucleus-nucleus systems, including neutron-rich and proton-rich isotopes, in the energy range of 50-400 MeV/u. The GOP is derived from the microscopic folding model with the complex G-matrix interaction CEG07 and the global density presented by the São Paulo group. The folding model accounts for realistic complex optical potentials of nucleus-nucleus systems well 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, 8-22C, 12-24O, 16-38Ne, 20-40Mg, 22-48Si, 26-52S, 30-62Ar, and 34-70Ca, scattered by stable target nuclei of 12C, 16O, 28Si, 40Ca 58Ni, 90Zr, 120Sn, and 208Pb at incident energies 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 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.

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

2012-04-01

64

Event-by-event pseudo-rapidity fluctuations in high energy nucleus-nucleus interactions  

NASA Astrophysics Data System (ADS)

A detailed study of event-by-event pseudo-rapidity fluctuations in relativistic heavy-ion collisions in terms of the ? measure and its multiplicity and target dependence has been carried out for heavy (AgBr) and light (CNO) groups of targets present in the nuclear emulsion using O16 (at an incident momentum of 4.5 A?GeV/c), Ne22 (at an incident momentum of 4.1 A?GeV/c), Si28 (at an incident momentum of 4.5 A?GeV/c) and S32 (at an incident momentum of 4.5 A?GeV/c) projectiles. For all the interactions, the total ensemble of events has been divided into three overlapping multiplicity classes depending on the number of shower particles. For all the interactions and for each multiplicity class, the ? values are found to be greater than zero indicating the presence of strong correlation in the multiparticle production at Dubna energy. The measured ? values are found to decrease with the increase of average multiplicity for all the interactions. The ? values for the AgBr target are found to be greater than that for the CNO target for all the projectiles. This observation indicates the presence of stronger correlation for heavier projectiles. The experimental results have been compared with the modified FRITIOF model. It has been seen that the modified FRITIOF model cannot reproduce the experimental results.

Bhattacharyya, Swarnapratim; Haiduc, Maria; Neagu, Alina Tania; Firu, Elena

2013-10-01

65

Consistent parametrisation for the production rates of negatively charged hadrons and neutral strange particles in nucleon-nucleon, nucleon-nucleus and nucleus-nucleus collisions.  

National Technical Information Service (NTIS)

A parametrisation of negative hadron and neutral strange particle production was developed which consistently describes presently available data from nucleon-nuceon, nucleon-nucleus, and nucleus-nucleus collisions at a beam energy of 200 GeV per nucleon. ...

K. Kadija I. Derado N. Schmitz P. Seyboth

1994-01-01

66

Experimental Data on pi -Mesons Produced in Inelastic and Central Nucleus-Nucleus Interactions at 4.5 GeV/C Momentum Per Nucleon.  

National Technical Information Service (NTIS)

Experimental data on pi exp - -meson production in central and inelastic nucleus-nucleus interactions at 4.5 GeV/c per nucleon momentum are presented in tables. The data were obtained in the streamer chamber, SKM-200, with Li, C, Ne, Al, Cu, Zr and Pb tar...

M. Anikina A. Abdurakhimov V. Aksinenko

1984-01-01

67

Study of lambda -Production in Central Nucleus-Nucleus Interactions at the Momentum of 4.6 GeV/C Per Incident Nucleon.  

National Technical Information Service (NTIS)

Transverse momenta and rapidities of lambda particles produced in central nucleus-nucleus collisions at 4.5 GeV/c per nucleon (CC, CNe, ONe, CCu, CZr, CPb, OPb) have been studied and compared with those from inelastic He-Li interactions at the same incide...

M. Anikina A. Golokhvastov L. Goncharova

1983-01-01

68

Development of the Hamiltonian molecular dynamics (HMD) model: A first-principles, relativistic description of nucleus-nucleus interactions at medium energy  

NASA Astrophysics Data System (ADS)

Simulation of energetic, colliding nuclear systems at energies between 100 AMeV and 5 AGeV has utility in fields as diverse as the design and construction of fundamental particle physics experiments, patient treatment by radiation exposure, and in the protection of astronaut crews from the risks of exposure to natural radiation sources during spaceflight. Descriptions of these colliding systems which are derived from theoretical principles are necessary in order to provide confidence in describing systems outside the scope of existing data, which is sparse. The system size and velocity dictate descriptions which include both special relativistic and quantum effects, and the currently incomplete state of understanding with respect to the basic processes at work within nuclear matter dictate that any description will exist at some level of approximation. Models commonly found in the literature employ approximations to theory which lead to simulation results which demonstrate departure from fundamental physical principles, most notably conservation of system energy. The HMD (Hamiltonian Molecular Dynamics) mode is developed as a phase-space description of colliding nuclear system on the level of hadrons, inclusive of the necessary quantum and relativistic elements. Evaluation of model simulations shows that the HMD model shows the necessary conservations throughout system simulation. HMD model predictions are compared to both the RQMD (Relativistic Quantum Molecular Dynamics) and JQMD (Jaeri-Quantum Molecular Dynamics) codes, both commonly employed for the purpose of simulating nucleus-nucleus collisions. Comparison is also provided between all three codes and measurement. The HMD model is shown to perform well in light of both measurement and model calculation, while providing for a physically self-consistent description of the system throughout.

Zapp, Edward Neal

69

Relativistic heavy-ion experiments  

SciTech Connect

Objectives of high energy nucleus-nucleus studies are outlined. Bevalac experiments on the formation of hot high-density equilibrated nuclear matter are discussed. Future programs are outlined, including research at the CERN ISR.

Pugh, H.G.

1981-08-01

70

Light-isotope production in relativistic Au-induced nucleus-nucleus reactions  

NASA Astrophysics Data System (ADS)

We present measurements of p,d,3He, and 4He nuclei produced in collisions of 11.5 A GeV/c Au projectiles with Au and Pb nuclei. The data were recorded at the Brookhaven National Laboratory AGS facility by two magnetic-spectrometer experiments, E864 and E878. The produced particles are measured at rapidities near the center of mass for low transverse momenta (pT < 400 MeV/c per nucleon). We compare the measurements from E864 and E878 with one another and with preliminary proton and deuteron measurements from AGS experiment E866. We observe an excess of protons in the E864 data as compared to the E878 data; this excess can be partly explained by the differing sensitivities of the two experiments to protons produced in hyperon decays. We find reasonable agreement between the nucleus yields in all three experiments. We discuss the mass dependence of the proton and light- nucleus yields in the 10% most-central collisions. We compute coalescence ratios, and examine their dependence on the transverse momenta of the produced nuclei, the size and kinetic energy of the colliding system, and the centrality of the collision. We also compare the data with the predictions of coalescence calculations based on microscopic cascade models; this theoretical framework is found to describe proton and deuteron production adequately for certain combinations of parameters, but fails to reproduce the yields of heavier species.

Pope, Joseph Kyle

1998-11-01

71

Universality of multifragmentation of residual nuclei produced in high-energies nucleus-nucleus interactions  

Microsoft Academic Search

Experimental data on the multifragmentation of residual nuclei produced in the krypton interactions with photoemulsion nuclei\\u000a at 0.9 GeV per projectile nucleon are presented and compared with similar data on fragmentation from experiments where gold\\u000a nuclei of energy 10.7 GeV per nucleon appear as projectiles. It is shown for the first time that there exist two modes of\\u000a nuclear multifragmentation,

A. Abd-Elhafiez; V. Sh. Navotny; V. V. Uzhinskii; G. I. Orlova; M. M. Chernyavski

2001-01-01

72

Kaon production in nucleus-nucleus collisions at 92 MeV per nucleon  

NASA Astrophysics Data System (ADS)

K+ production far below the free nucleon-nucleon threshold has been investigated in collisions of 36Ar on 12C, nat Ti, and 181Ta targets at an incident energy of 92 MeV per nucleon. The cross sections for K+ production have been inferred from the observed muon decays of positive kaons. The results are discussed in the framework of a participant-spectator model and are compared to proton induced K+ production and to subthreshold pion production experiments.

Legrain, R.; Lecolley, J. F.; Lecolley, F. R.; Alamanos, N.; Bianchi, L.; Cassagnou, Y.; Dabrowski, H.; Erazmus, B.; Julien, J.; Lebrun, D.; Le Brun, Ch.; Mougeot, A.; Hameau, P.; Perrin, G.; de Saintignon, P.; Sida, J. L.; Wieleczko, J. P.

1999-03-01

73

Particle Production in Nucleus-Nucleus Collisions at the SPS and the QCD Phase Diagram  

SciTech Connect

Results of the NA49 experiment on particle production in the energy regime of the CERN-SPS are reviewed. In order to collect information on the properties of the QCD phase diagram systematic studies of the energy dependence of particle production in heavy ion collisions have been performed. Net-baryon distributions and results on strangeness production are discussed. Recent attempts to search for a critical point, such as multiplicity fluctuations and the transverse mass dependence of anti-baryon/baryon ratios are reviewed.

Blume, Christoph [Institut fuer Kernphysik, J.W. Goethe-Universitaet, Max-von-Laue-Str. 1, D-60438 Frankfurt am Main (Germany)

2011-05-23

74

Two-Particle Correlations and Excited State Populations in Nucleus-Nucleus Collisions.  

NASA Astrophysics Data System (ADS)

Two particle correlation functions and excited state populations were measured for the ^3 He + Ag reactions at E/A = 67 MeV and the ^{36}Ar + ^{197 }Au reactions at E/A = 35 MeV. In the former experiment, measurements were performed with a position sensitive high resolution hodoscope as a standalone device. In the latter experiment, measurements were performed by combining the high resolution hodoscope with the Miniball, a 4 pi multifragment detection array. These two experiments addressed several outstanding problems in the interpretation of two particle correlation functions and emission temperatures. For the ^3He + Ag reactions at E/A = 67 MeV, p - p and d - alpha correlation functions were measured to address the scaling of two particle correlation functions with the size of the projectile. These measurements revealed that the correlation functions for charged particles scale naturally with the radius of the projectile, consistent with an emission volume which is initially defined by the overlap of a much smaller projectile with a much larger target. The radii extracted from d - alpha correlations were much smaller than the ones extracted from p - p correlations, an effect which may be related to the fact that deuterons and alpha particles have shorter mean free paths within the nuclear medium. The populations of excited states were also measured at forward and at backward angles in order to compare the emission temperatures for pre-equilibrium and equilibrium emission mechanisms. A low emission temperature of about 1 MeV was obtained for ^6Li particles evaporated at backward angles. This low temperature was consistent, however, with a hybrid pre-equilibrium transport and equilibrium evaporation model. Much larger temperatures of about 4 MeV were observed for pre-equilibrium processes measured at forward angles. Impact parameter selected excited state populations were measured for ^{36}Ar + ^{197}Au reactions at E/A = 35 MeV in order to better understand the population inversions observed in a previous measurement of ^{14}N + Ag reactions at E/A = 35 MeV. These impact parameter selected measurements revealed such population inversions to be an effect most prominent in low multiplicity peripheral reactions. When the multiplicity of charge particles is increased to the value consistent with central collisions, the excited state population approaches the statistical model predictions for T ~ 4 MeV.

Zhu, Fan

1992-09-01

75

Quark Matter 2004: The 17th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Oakland, California, USA, 11-17 January 2004)  

Microsoft Academic Search

The Quark Matter 2004 conference was held on 11--17 January 2004 at the Oakland Marriott City Center Hotel in downtown Oakland, California. It was the 17th International Conference on Ultra-Relativistic Nucleus--Nucleus Collisions, held for the third time in California. The conference was preceded by two well-attended meetings: a pre-conference symposium for young scientists and a workshop for local high school

Hans Georg Ritter; Xin-Nian Wang

2004-01-01

76

A consistent parametrisation for the production rates of negatively charged hadrons and neutral strange particles in nucleon-nucleon, nucleon-nucleus and nucleus-nucleus collisions  

Microsoft Academic Search

A parametrisation of negative hadron and neutral strange particle production was developed which consistently describes presently available data from nucleon-nucleon, nucleon-nucleus and nucleus-nucleus collisions at a beam energy of 200 GeV per nucleon. Average multiplicities of negative hadrons are found to be proportional to the number of wounded nucleons, averageKs0 multiplicities proportional to the number of wounded quarks, and average

K. Kadija; I. Derado; N. Schmitz; P. Seyboth

1995-01-01

77

Revised Landau hydrodynamic model and the pseudorapidity distributions of charged particles produced in nucleus-nucleus collisions at maximum energy at the BNL Relativistic Heavy Ion Collider  

NASA Astrophysics Data System (ADS)

By using the revised Landau hydrodynamic model and taking into account the effect of leading particles, we discuss the pseudorapidity distributions of produced charged particles in nucleus-nucleus collisions at high energy. The theoretical results are in good agreement with the experimental measurements carried out by PHOBOS Collaboration in different centrality Au+Au and Cu+Cu collisions at the maximum energy of sNN=200GeV at the BNL Relativistic Heavy Ion Collider.

Jiang, Z. J.; Li, Q. G.; Zhang, H. L.

2013-04-01

78

Nucleus-nucleus cold fusion reactions analyzed with the l-dependent 'fusion by diffusion' model  

SciTech Connect

We present a modified version of the Fusion by Diffusion (FBD) model aimed at describing the synthesis of superheavy nuclei in cold fusion reactions, in which a low excited compound nucleus emits only one neutron. The modified FBD model accounts for the angular momentum dependence of three basic factors determining the evaporation residue cross section: the capture cross section {sigma}{sub cap}(l), the fusion probability P{sub fus}(l), and the survival probability P{sub surv}(l). The fusion hindrance factor, the inverse of P{sub fus}(l), is treated in terms of thermal fluctuations in the shape degrees of freedom and is expressed as a solution of the Smoluchowski diffusion equation. The l dependence of P{sub fus}(l) results from the l-dependent potential energy surface of the colliding system. A new parametrization of the distance of starting point of the diffusion process is introduced. An analysis of a complete set of 27 excitation functions for production of superheavy nuclei in cold fusion reactions, studied in experiments at GSI Darmstadt, RIKEN Tokyo, and LBNL Berkeley, is presented. The FBD model satisfactorily reproduces shapes and absolute cross sections of all the cold fusion excitation functions. It is shown that the peak position of the excitation function for a given 1n reaction is determined by the Q value of the reaction and the height of the fission barrier of the final nucleus. This fact could possibly be used in future experiments (with well-defined beam energy) for experimental determination of the fission barrier heights.

Cap, T.; Siwek-Wilczynska, K.; Wilczynski, J. [Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Hoza 69, PL-00-681 Warsaw (Poland); Andrzej Soltan Institute for Nuclear Studies, PL-05-400 Otwock-Swierk (Poland)

2011-05-15

79

Partition of cross sections in asymmetric nucleus-nucleus reactions and the origin of fast alpha particles  

SciTech Connect

To investigate the mechanism of asymmetric nucleus-nucleus reactions from the Coulomb barrier to intermediate energies the /sup 14/N + /sup 159/Tb reaction was studied at five bombarding energies between 8 and 23 MeV/u via particle-particle correlations (at selected energies) and particle KX-ray coincidences to identify the specific reaction channels. With the KX-ray method partial cross sections for projectile-like fragments (PLF) as a function of the atomic number (Z/sub res/) of the residual nucleus can be determined. The charge balance yields the ''missing charge'' dZ = Z/sub proj/ + Z/sub targ/ - Z/sub PLF/ - Z/sub TLF/ that indicates whether, in addition to the PLF, other charged particles are emitted. A large fraction of the inclusive cross sections is found to originate from such channels with two or more fragments in the exit channel, and this fraction increases as the PLF is further removed in mass from the incident projectile, and with increasing bombarding energy. From the particle-particle correlation studies it is found that sequential decays of PLF's are dominant. ''Non-sequential'' processes, if present, are associated with inelastic reactions involving excitations of both projectile and target. The bulk of the large alpha-particle cross section at small angles is found to be associated with channels in which, in addition to the alpha particle, only nucleons and other alpha particles are emitted. From ..gamma..-ray multiplicity measurements and from the broad distribution of the strength with Z/sub res/ it is concluded that these alpha particles originate from inelastic (damped) processes. 27 refs., 10 figs.

Siemssen, R.H.

1985-01-01

80

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

NASA Astrophysics Data System (ADS)

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.

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

81

The influence of flocculation on the ultrasonic properties of emulsions: experiment  

NASA Astrophysics Data System (ADS)

Droplet flocculation in oil-in-water emulsions has been monitored by ultrasonic attenuation spectroscopy, a technique which is sensitive to changes in the spatial distribution of the droplets within an emulsion. The ultrasonic attenuation spectra (1-150 MHz) of a series of 5 wt% corn oil-in-water emulsions (0022-3727/31/20/032/img1m) were recorded at 250022-3727/31/20/032/img2C. Depletion flocculation was induced in the emulsions by adding various concentrations (7-100 mM) of sodium dodecyl sulphate to the aqueous phase. At low frequencies, the attenuation coefficient of the emulsions decreased with flocculation due to overlap of the thermal waves generated by the droplets. At high frequencies, the attenuation coefficient increased with flocculation due to an increase in scattering by the flocs. The results could be explained using an effective medium theory recently developed to account for the influence of droplet flocculation on the ultrasonic properties of emulsions. The ultrasonic technique was also used to monitor the breakdown of flocs under shear flow. The dependence of the ultrasonic properties of emulsions on flocculation means that ultrasonic attenuation spectroscopy can be used to study interactions among droplets in concentrated emulsions.

Chanamai, Ratjika; Herrmann, Norbert; McClements, D. Julian

1998-10-01

82

Nucleus-nucleus collisions at 60 to 200 GeV/nucleon: Results from the WA80 experiment at CERN  

SciTech Connect

Results from {sup 16}O- and {sup 32}S-induced reactions obtained by the WA80 collaboration at the CERN SPS are presented with reference to global event characteristics such as collision geometry, the degree of nuclear stopping, and the energy density attained. Transverse momentum spectra of neutral pions and of direct photons are also presented. At an accuracy within 15{percent} limits, all observed photons are accounted for by known hadronic decays. 13 refs., 8 figs., 1 tab.

Plasil, F.; Awes, T.C.; Baktash, C.; Ferguson, R.L.; Lee, I.Y.; Saini, S.; Tincknell, M.L.; Young, G.R. (Oak Ridge National Lab., TN (USA)); Obenshain, F.E.; Sorensen, S.P. (Oak Ridge National Lab., TN (USA) Tennessee Univ., Knoxville, TN (USA)); Albrecht, R.; Bock, R.; Claesson, G.; Gutbrod, H.H.; Kolb, B.W.; Lund, I.; Schmidt, H.R.; Siemiarczuk, T. (Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germa

1990-05-01

83

System-size dependence of strangeness production in nucleus-nucleus collisions at squareroot[sNN]=17.3 GeV.  

PubMed

Emission of pi+/-, K+/-, phi, and Lambda was measured in near-central C+C and Si+Si collisions at 158 AGeV beam energy. Together with earlier data for p+p, S+S, and Pb+Pb, the system-size dependence of relative strangeness production in nucleus-nucleus collisions is obtained. Its fast rise and the saturation observed at about 60 participating nucleons can be understood as the onset of the formation of coherent systems of increasing size. PMID:15783629

Alt, C; Anticic, T; Baatar, B; Barna, D; Bartke, J; Betev, L; Bia?kowska, H; Billmeier, A; Blume, C; Boimska, B; Botje, M; Bracinik, J; Bramm, R; Brun, R; Bunci?, P; Cerny, V; Christakoglou, P; Chvala, O; Cramer, J G; Csató, P; Darmenov, N; Dimitrov, A; Dinkelaker, P; Eckardt, V; Farantatos, G; Flierl, D; Fodor, Z; Foka, P; Freund, P; Friese, V; Gál, J; Ga?dzicki, M; Georgopoulos, G; G?adysz, E; Grebieszkow, K; Hegyi, S; Höhne, C; Kadija, K; Karev, A; Kliemant, M; Kniege, S; Kolesnikov, V I; Kollegger, T; Kornas, E; Korus, R; Kowalski, M; Kraus, I; Kreps, M; van Leeuwen, M; Lévai, P; Litov, L; Lungwitz, B; Makariev, M; Malakhov, A I; Markert, C; Mateev, M; Mayes, B W; Melkumov, G L; Meurer, C; Mischke, A; Mitrovski, M; Molnár, J; Mrówczy?ski, St; Pálla, G; Panagiotou, A D; Panayotov, D; Petridis, A; Pikna, M; Pinsky, L; Pühlhofer, F; Reid, J G; Renfordt, R; Richard, A; Roland, C; Roland, G; Rybczy?ski, M; Rybicki, A; Sandoval, A; Sann, H; Schmitz, N; Seyboth, P; Siklér, F; Sitar, B; Skrzypczak, E; Stefanek, G; Stock, R; Ströbele, H; Susa, T; Szentpétery, I; Sziklai, J; Trainor, T A; Trubnikov, V; Varga, D; Vassiliou, M; Veres, G I; Vesztergombi, G; Vrani?, D; Wetzler, A; W?odarczyk, Z; Yoo, I K; Zaranek, J; Zimányi, J

2005-02-07

84

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

SciTech Connect

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.

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

85

A search for the production of direct leptons in nucleon-nucleus and nucleus-nucleus collisions  

SciTech Connect

This report discusses the following topics: subthreshold production experiment; testing and selection of PCOS amplifiers; transverse energy detector; development of a sensitive new amplifiers; single-lepton experiment. (LSP)

Kirk, P.N.

1990-12-01

86

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  

SciTech Connect

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.

Jones, W.V.; Wefel, J.P.

1985-01-01

87

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 Astrophysics Data System (ADS)

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.

Jones, W. V.; Wefel, J. P.

88

Cosmic ray results from the jacee experiments  

NASA Astrophysics Data System (ADS)

Studies of high-energy nucleus-nucleus interactions with balloon-borne JACEE emulsion chambers are summarized. High energy, high multiplicity interactions are found with high-energy-density (>= 2 GeV/fm3), high observed values (500 - 2,000 MeV/c), and several interesting pseudorapidity and/or azimuthal structures. Very short-range correlations of charged particles, and several other inclusive characteristics are discussed.

Yoshiyuki, Takahashi; Shoji, Dake; Burnett, T. H.; Dake, S.; Derrickson, J. H.; Fountain, W. F.; Fuki, M.; Gregory, J. C.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W. V.; Jurak, A.; Lord, J. J.; Meegan, C. A.; Miyamura, O.; Oda, H.; Ogata, T.; Parnell, T. A.; Roberts, E.; Strausz, S.; Tabuki, T.; Takahashi, Y.; Tominaga, T.; Wefel, J. P.; Watts, J. W.; Wilczynska, B.; Wilkes, R. J.; Wolter, W.; Wosiek, B.

1987-01-01

89

Pion production in nucleus-nucleus collisions below a few GeV/nucleon: past, present and future  

SciTech Connect

A general review of experimental data on pion production in A-A collisions for incident energies below a few GeV/nucleon is presented. Early data on inclusive pion spectra, which served as the genesis for present pion measurements, are discussed. The majority of the paper is devoted to present pion experiments, with an emphasis being placed on what such experiments tell about the general features of high-energy A-A collisions. Particular attention is given to multipion production as studied in recent streamer chamber experiments. The review ends with projections on future experiments with the heavier beams that will be available in 1982 at Berkeley, and the higher-energy beams that will hopefully be available in the not too distant future. 39 figures.

Schroeder, L.S.

1980-07-01

90

Kinematic and centrality dependencies of light-isotope production in relativistic gold-induced nucleus-nucleus reactions  

NASA Astrophysics Data System (ADS)

The invariant yields of proton, deuteron, triton and helium-3 nuclei produced in collisions of 11.6 A GeV/c Au projectiles incident upon a Pb target are presented. The data were recorded at the Brookhaven National Laboratory AGS facility by the magnetic spectrometer experiment E864. The produced particles are measured within one unit of mid-rapidity and for low transverse momentum ( /<= 600MeV/c). The yields were measured for three different impact parameter ranges as defined by the event charged particle multiplicity. These three ranges correspond to the top 0-10%, 10-38% and 38-66% of the charged particle multiplicity distribution. The measurements are compared with preliminary experimental data sets from other experiments. In general reasonable agreement is found. An examination of the rapidity and transverse momentum dependence of the invariant yields for each centrality bin is made. Coalescence ratios are computed and their kinematic and centrality dependence examined. In addition source radii are extracted, and evidence of mt scaling of these radii is explored. The mass and centrality dependence of the transverse momentum shapes are presented. Interpretations in terms of coalescence models are given. The predictions of coalescence calculations based on microscopic cascade models are compared to the data. It is found that the helium-3 yields are consistently under-predicted for all centralities, where as the proton and deuteron show similar levels of agreement to the data for all centralities.

George, Nigel Keith

1999-11-01

91

Exclusive vector mesons at high energies: from photon-proton to proton-proton and nucleus-nucleus collisions  

NASA Astrophysics Data System (ADS)

Photoproduction of vector mesons has been studied since the 1960's and was instrumental in establishing the hadronic structure of the photon and the concept of vectormeson dominance. More recently our knowledge on vector meson photoproduction has been furthered by experiments at the HERA accelerator. Total cross sections ans well as a number of kinematical distributions have been measured from light to heavy vector mesons. These experiments have been a testbed of ideas on the production mechanism, the QCD Pomeron exchange. In particular in varying the mass of the vector meson we can study the Pomeron exchange from the soft to the perturbatively hard regimes. The production mechanism also contains information on the quark-antiquark wave function of the produced meson. High energy protons or ions are the source of a flux of Weizsäcker-Williams photons, which can be utilized to study the photoproduction of vector mesons also at the Tevatron and LHC colliders. We discuss how information on the small-x gluon distribution in protons in nuclei can be obtained. Besides this intrinsic interest in vector meson production, a precise knowledge thereof is also necessary for odderon searches. In this regard, we discuss also transverse momentum distributions including absorption effects.

Schäfer, Wolfgang

2012-12-01

92

Attained energy densities and neutral pion spectra in nucleus-nucleus collisions at 200 GeV/nucleon  

SciTech Connect

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. 18 refs., 2 figs.

Plasil, F.; Albrecht, R.; Awes, T.C.; Baktash, C.; Beckmann, P.; Berger, F.; Bock, R.; Claesson, G.; Clewing, G.; Dragon, L.

1989-01-01

93

Fully differential cross sections for C6+ single ionization of helium: the role of nucleus nucleus interaction  

NASA Astrophysics Data System (ADS)

In this work, we present fully differential cross section (FDCS) calculations using distorted wave theories for helium single ionization by 2 MeV amu-1 C6+ ions. We study the influence of internuclear interaction on low-energy electron emission in the scattering plane. It is shown that by incorporating an internuclear effective charge which depends on the collision momentum transfer and taking into account its interplay with passive electron screening we obtain better agreement with experiments in most cases under consideration. Comparisons are made with absolute experimental measurements and with other theories. We found that for ejected-electron momentum similar to transferred momentum, internuclear potential effects have little contribution to FDCSs.

Ciappina, M. F.; Cravero, W. R.

2006-05-01

94

Systematic study of projectile fragments in nucleus-nucleus collisions at 4.1-4.5 A GeV/c and multi-source thermal model  

NASA Astrophysics Data System (ADS)

The multiplicity distributions of projectile fragments (PFs) produced in interactions of (4He, 12C, 16O, 22Ne and 28Si with emulsion (Em) at 4.1-4.5 A GeV/ c beam energies, and their dependence on target groups (H, CNO and AgBr) are presented and have been reproduced by using a multi-source thermal model. The dependence of the mean multiplicities on masses of projectile and target nuclei is investigated. The experimental results are compared with the corresponding ones from the theoretically calculated ones. The experimental results agree with theoretical calculations using the multi-source thermal model.

Rahim, M. A.; Fakhraddin, S.; Asharabi, H.

2012-08-01

95

Gamma ray observation with emulsion hybrid telescope  

Microsoft Academic Search

A new gamma ray observation project with balloon borne emulsion chambers is presented. A new technique based on the accelerator emulsion experiments was implemented for studying high energy stellar objects with cosmic gamma rays. This paper provides the aim and concept of this project as well as some results of test experiments.

S. Aoki; K. Kodam; J. Kawada; N. Nonaka; A. Suzuki; T. Hara; Y. Watanabe; H. Rokujyo; A. Ariga; M. Kazuyama; H. Kubota; M. Komatsu; T. Sako; O. Sato; Y. Taira; S. Takahashi; N. Naganawa; T. Nakano; M. Nakamura; K. Niwa; Y. Nonoyama; K. Hamada; T. Fukuda; T. Furukawa; K. Hoshino; M. Miyanishi; S. Miyamoto; K. Morishima; T. Yoshioka; J. Yoshida; A. Iyono; Y. Sato; I. Tezuka

2009-01-01

96

Emulsion experiment for study on energy spectra of protons and nuclei of primary cosmic radiation in the energy range greater than 10 TeV per particle  

NASA Astrophysics Data System (ADS)

Development of the emulsion chamber method to study the energy spectrum of protons and nuclei of primary cosmic radiation is described; the results obtained in long-term exposure of emulsion chambers in the stratospere are presented.

Varkovitskaya, A. Ya.; Zamchalova, E. A.; Zatsepin, V. I.; Sazhina, G. P.; Sokolskaya, N. V.

97

Spray-dried whey protein\\/lactose\\/soybean oil emulsions. 2. Redispersability, wettability and particle structure  

Microsoft Academic Search

In the present paper redispersion and wettability experiments of spray-dried whey protein-stabilized emulsions are presented. Emulsion droplet size after redispersion gives information about eventual coalescence between emulsion droplets in the powder matrix during drying or storage, resulting in an increase in emulsion droplet size after redispersion. Results from redispersion experiments are combined with previously presented knowledge about powder surface composition

Pia Fäldt; Björn Bergenståhl

1996-01-01

98

Emulsions: Principles and Preparation  

Microsoft Academic Search

Emulsions are mixtures of fluids that are immiscible. Usually one fluid is present as small droplets in another phase. There\\u000a are emulsions of oil in water, called oil-inwater emulsions (abbreviated as O\\/W), but also emulsions of water in oil (W\\/O).\\u000a The droplet phase is called the dispersed phase, the surrounding phase the continuous phase. Emulsions are important in a\\u000a great

Remko M. Boom

99

New event types in a balloon-borne cosmic ray experiment  

SciTech Connect

Proton-nucleus interactions at the mean energy of about 45 TeV and nucleus-nucleus interactions at energies greater than 1 TeV/nucleon are being studied with a balloon borne emulsion chamber. The multiplicities of charged secondaries, the fractional energy spectra and transverse momentum distribution of gamma rays, and the rapidity density in the central region are obtained. The features of inelastic proton-nucleus interactions are as expected from extrapolations of measurements at lower energies. On the other hand, preliminary data on nucleus-nucleus interactions indicate some features not expected by simple superposition of nucleon-nucleon interactions. Examples of unusual phenomena include one event with multiplicity N/sub s/ similarly ordered 1000 and several events with apparent high P/sub T/ particle production.

Burnett, T.H.; Dake, S.; Fuki, M.; Gregory, J.C.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W.V.; Jurak, A.; Lord, J.J.; Miyamura, O.

1982-01-01

100

Time stamp technique using a nuclear emulsion multi-stage shifter for gamma-ray telescope  

Microsoft Academic Search

Nuclear emulsion has a potential use as a gamma-ray telescope with high angular resolution. For this application it is necessary to know the time when each track was recorded in the emulsion. In previous experiments using nuclear emulsion, various efforts were used to associate time to nuclear emulsion tracks and to improve the time resolution. Using a high speed readout

Satoru Takahashi; Shigeki Aoki; Hiroki Rokujo; Kaname Hamada; Masahiro Komatsu; Kunihiro Morishima; Mitsuhiro Nakamura; Toshiyuki Nakano; Kimio Niwa; Osamu Sato; Teppei Yoshioka; Koichi Kodama

2010-01-01

101

Search for new states of matter with the STAR experiment at RHIC  

Microsoft Academic Search

High energy nucleus-nucleus collisions are used for the search for the Quark-Gluon Plasma, a state of matter predicted by lattice QCD. Since 1999, the STAR experiment recorded in total ? 10 × 106Au + Au events at ?s=130 GeV and 200 GeV which were analyzed to determine the temperature, size and density of the collision system.

Jens Sören Lange

2003-01-01

102

Forward backward studies of Ne-22(Si-28)-emulsion interactions at (4.1-4.5) AGeV/c  

NASA Astrophysics Data System (ADS)

The characteristics of nucleus-nucleus collisions at high energies are investigated for the interaction of Ne-22 and Si-28 with emulsion nuclei . The multiplicity and correlations of the forward (theta < 90 degrees) and backward (theta >= 90 degrees) secondary particles emitted are calculated according to the modified cascade and modified Fritiof models. The predictions of the two models are compared with experimental data at an incident momentum of (4.1-4.5) GeV/c per nucleon. Both models depend on the Monte Carlo techniques where the modified cascade model implies the superposition of nucleon-nucleon interactions, and the modified Fritiof model utilizes the Regge theory for the description of the cascading process. Comparison with data shows no clear preference of one model over the other. However, the modified Fritiof model seems to be nearer to the experimental data than the modified cascade model.

Abdel-Aziz, S. S.

2006-10-01

103

System-size and centrality dependence of charged kaon and pion production in nucleus-nucleus collisions at 40A GeV and 158A GeV beam energy  

NASA Astrophysics Data System (ADS)

Measurements of charged pion and kaon production are presented in centrality selected Pb+Pb collisions at 40A GeV and 158A GeV beam energy as well as in semicentral C+C and Si+Si interactions at 40A GeV. Transverse mass spectra, rapidity spectra, and total yields are determined as a function of centrality. The system-size and centrality dependence of relative strangeness production in nucleus-nucleus collisions at 40A GeV and 158A GeV beam energy are derived from the data presented here and from published data for C+C and Si+Si collisions at 158A GeV beam energy. At both energies a steep increase with centrality is observed for small systems followed by a weak rise or even saturation for higher centralities. This behavior is compared to calculations using transport models (ultra-relativistic quantum molecular dynamics and hadron-string dynamics), a percolation model, and the core-corona approach.

Anticic, T.; Baatar, B.; Barna, D.; Bartke, J.; Beck, H.; Betev, L.; Bia?kowska, H.; Blume, C.; Bogusz, M.; Boimska, B.; Book, J.; Botje, M.; Bun?i?, P.; Cetner, T.; Christakoglou, P.; Chung, P.; Chvala, O.; Cramer, J. G.; Dinkelaker, P.; Eckardt, V.; Fodor, Z.; Foka, P.; Friese, V.; Ga?dzicki, M.; Grebieszkow, K.; Höhne, C.; Kadija, K.; Karev, A.; Kliemant, M.; Kolesnikov, V. I.; Kollegger, T.; Kowalski, M.; Kresan, D.; Laszlo, A.; Lacey, R.; van Leeuwen, M.; Lungwitz, B.; Mackowiak, M.; Makariev, M.; Malakhov, A. I.; Mateev, M.; Melkumov, G. L.; Mitrovski, M.; Mrówczy?ski, St.; Nicolic, V.; Pálla, G.; Panagiotou, A. D.; Peryt, W.; Pluta, J.; Prindle, D.; Pühlhofer, F.; Renfordt, R.; Roland, C.; Roland, G.; Rybczy?ski, M.; Rybicki, A.; Sandoval, A.; Schmitz, N.; Schuster, T.; Seyboth, P.; Siklér, F.; Skrzypczak, E.; Slodkowski, M.; Stefanek, G.; Stock, R.; Ströbele, H.; Susa, T.; Szuba, M.; Utvi?, M.; Varga, D.; Vassiliou, M.; Veres, G. I.; Vesztergombi, G.; Vrani?, D.; W?odarczyk, Z.; Wojtaszek-Szwarc, A.

2012-11-01

104

A search for the production of direct leptons in nucleon-nucleus and nucleus-nucleus collisions. Progress report, April 1, 1992--December 1, 1992  

SciTech Connect

Activities included contributions to the AMY Collaboration, the transverse energy detector, the Di-Lepton Spectrometer, with emphasis on the single-lepton experiment. Elastic and inelastic scattering differential cross sections and total cross sections are shown for {pi}{sup +} and {pi}{sup {minus}} on {sup 9}Be and C.

Kirk, P.N. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy

1992-12-15

105

Multiple emulsions: an overview.  

PubMed

Multiple emulsions are complex polydispersed systems where both oil in water and water in oil emulsion exists simultaneously which are stabilized by lipophillic and hydrophilic surfactants respectively. The ratio of these surfactants is important in achieving stable multiple emulsions. Among water-in-oil-in-water (w/o/w) and oil-in-water-in-oil (o/w/o) type multiple emulsions, the former has wider areas of application and hence are studied in great detail. Formulation, preparation techniques and in vitro characterization methods for multiple emulsions are reviewed. Various factors affecting the stability of multiple emulsions and the stabilization approaches with specific reference to w/o/w type multiple emulsions are discussed in detail. Favorable drug release mechanisms and/or rate along with in vivo fate of multiple emulsions make them a versatile carrier. It finds wide range of applications in controlled or sustained drug delivery, targeted delivery, taste masking, bioavailability enhancement, enzyme immobilization, etc. Multiple emulsions have also been employed as intermediate step in the microencapsulation process and are the systems of increasing interest for the oral delivery of hydrophilic drugs, which are unstable in gastrointestinal tract like proteins and peptides. With the advancement in techniques for preparation, stabilization and rheological characterization of multiple emulsions, it will be able to provide a novel carrier system for drugs, cosmetics and pharmaceutical agents. In this review, emphasis is laid down on formulation, stabilization techniques and potential applications of multiple emulsion system. PMID:17076645

Khan, Azhar Yaqoob; Talegaonkar, Sushama; Iqbal, Zeenat; Ahmed, Farhan Jalees; Khar, Roop Krishan

2006-10-01

106

Extending Temporary Storage Capacity with Emulsion Breakers  

Microsoft Academic Search

The objective this study was to further the understanding of the use of emulsion breakers injected into an oil spill recovery system at both lab-scale (at SL Ross) and mid-scale (at Ohmsett). The experiments were designed to assess the injection\\/mixing\\/settling regimes required for optimum water-removal performance from a meso-stable water-in-oil emulsion with an oil spill demulsifier. Various injection locations (skimmer

I. Buist; A. Lewis; A. Guarino; D. Devitis; K. Nolan; B. Smith

107

Development of a membrane-assisted fluidized bed reactor - 1 - Gas phase back-mixing and bubble-to-emulsion phase mass transfer using tracer injection and ultrasound experiments  

Microsoft Academic Search

A small laboratory-scale membrane-assisted fluidized bed reactor (MAFBR) was constructed in order to experimentally demonstrate the benefits of this reactor concept, especially the enhanced bubble-to-emulsion phase mass transfer and the reduced overall axial gas phase back-mixing, due to the presence of the membranes and permeation of gas through the membranes. With steady-state tracer gas injection experiments, it was demonstrated that

S. A. R. K. Deshmukh; J. A. Laverman; A. H. G. Cents; Sint Annaland van M; J. A. M. Kuipers

2005-01-01

108

Oil emulsions of fluorosilicone fluids  

SciTech Connect

Emulsions of fluorosilicone fluids in mineral oil are disclosed. These emulsions are stabilized by a polydimethylsiloxane-polybutadiene copolymer or a polydimethylsiloxane-hydrogenated polybutadiene copplymer. The emulsions are an effective foam suppressant for organic liquids, especially crude petroleum.

Keil, J. W.

1985-08-27

109

Demulsification of bitumen emulsions  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/W) emulsions is disclosed wherein water-soluble demulsifiers are used. These demulsifiers are salts of polymers and/or co-polymers of specific cationic monomers. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/C. wherein the demulsifier of the invention is contacted with the bituminous emulsion.

McCoy, D.R.; McEntire, E.E.

1983-09-20

110

Demulsification of bitumen emulsions  

SciTech Connect

A process for recovering bitumen from oil-in-water (o/w) emulsions is disclosed wherein water soluble demulsifiers are used. These demulsifiers are hydrophilic polyurethanes wherein the ethylene oxide content of the polyol portion of the polyurethane is greater than about 70% by weight. To resolve the bituminous petroleum emulsions, the process is carried out between 25 and 1200 C wherein the demulsifier of the invention is contacted with the bituminous emulsion.

Gipson, R.M.; Laberge, C.L.; Mccoy, D.R.; Young, K.B.

1982-03-23

111

Global Properties of Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

QCD as a theory of extended, strongly interacting matter is familiar from big bang evolution which, within the time interval from electro-weak decoupling (10-12 s) to hadron formation (5 × 10-6 s), is dominated by the expansion of quark-gluon matter, a color conducting plasma that is deconfined. In the 1970s deconfinement was predicted [1-5] to arise from the newly discovered “asymptotic freedom” property of QCD; i.e., the plasma was expected to be a solution of perturbative QCD at asymptotically high square momentum transfer Q 2, or temperature T

Kliemant, Michael; Sahoo, Raghunath; Schuster, Tim; Stock, Reinhard

112

Global Properties of Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

QCD as a theory of extended, strongly interacting matter is familiar from big bang evolution which, within the time interval from electro-weak decoupling (10-12 s) to hadron formation (5 × 10-6 s), is dominated by the expansion of quark-gluon matter, a color conducting plasma that is deconfined. In the 1970s deconfinement was predicted [1-5] to arise from the newly discovered "asymptotic freedom" property of QCD; i.e., the plasma was expected to be a solution of perturbative QCD at asymptotically high square momentum transfer Q 2, or temperature T

Kliemant, Michael; Sahoo, Raghunath; Schuster, Tim; Stock, Reinhard

113

Adiabatic approximation for nucleus-nucleus scattering  

SciTech Connect

Adiabatic approximations to few-body models of nuclear scattering are described with emphasis on reactions with deuterons and halo nuclei (frozen halo approximation) as projectiles. The different ways the approximation should be implemented in a consistent theory of elastic scattering, stripping and break-up are explained and the conditions for the theory's validity are briefly discussed. A formalism which links few-body models and the underlying many-body system is outlined and the connection between the adiabatic and CDCC methods is reviewed.

Johnson, R.C. [Department of Physics, School of Electronics and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom)

2005-10-14

114

The LHC as a nucleus nucleus collider  

NASA Astrophysics Data System (ADS)

This paper begins with a summary of the status of the Large Hadron Collider at CERN, including the lead-ion injector chain and the plans for the first phases of commissioning and operation with colliding proton beams. In a later phase, the LHC will collide lead nuclei at centre-of-mass energies of 5.5 TeV per colliding nucleon pair. This leap to 28 times beyond what is presently accessible will open up a new regime, not only in the experimental study of nuclear matter, but also in the beam physics of hadron colliders. Ultraperipheral and hadronic interactions of highly charged beam nuclei will cause beam losses that dominate the luminosity decay and may quench superconducting magnets, setting upper limits on luminosity and stored beam current. Lower limits are set by beam instrumentation. On the other hand, coherent radiation by the nuclear charges should provide natural cooling to overcome intra-beam scattering. As with protons, a flexible, staged approach to full performance will test the limits and make optimal use of scheduled beam time.

Jowett, John M.

2008-10-01

115

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 ... Before you administer fat emulsion, look at the solution closely. It should be free of floating material. Gently squeeze the bag or observe ...

116

Project blob: Edible emulsions  

Microsoft Academic Search

Most blobs are emulsions. From a chemistry perspective, emulsions turn two liquid phases into what appears to be one continuous phase through the use of surfactants. This lesson, created by a chemical engineering graduate student, allows the secondary students to observe this phenomenon in the transformation of vinegar, oil, and egg yolks into mayonnaise. The students, juniors at Western Hills

Amina Darwish; Mary Ann Schnieders; Andrea Burrows; Anant Kukreti; Stephen Thiel

2011-01-01

117

Rheology of double emulsions  

Microsoft Academic Search

New equations for the viscosity of concentrated double emulsions of core–shell droplets are developed using a differential scheme. The equations developed in the paper predict the relative viscosity (?r) of double emulsions to be a function of five variables: a\\/b (ratio of core drop radius to shell outer radius), ?21 (ratio of shell liquid viscosity to external continuous phase viscosity),

Rajinder Pal

2007-01-01

118

Lubrication of Aluminum Rolling by Oil-in-Water Emulsions  

Microsoft Academic Search

The dynamic concentration model for lubrication by oil-in-water emulsions proposed by Wilson el al. (1) is applied to strip rolling to derive a relatively simple equation for inlet film thickness. The predictions of the new model are supported by rolling experiments using emulsions as lubricants, where the film thickness is inferred from the surface roughness that is generated on the

Steven R. Schmid; William R. D. Wilson

1995-01-01

119

Analysis and experience with application of water-fuel oil emulsion at TGMP-314 and TGM-96 power-generating boilers  

Microsoft Academic Search

Combustion of water-fuel oil emulsions at high-capacity steam boilers of the TETs-23 cogeneration station is considered for\\u000a determining basic indices of their operation and for finding new ways for preventing emission of pollutants into the atmosphere.

N. A. Zroichikov; M. G. Lyskov; A. B. Bulgakov; E. A. Morozova

2006-01-01

120

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

PubMed

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

Tan, Hui Lin; McGrath, Kathryn M

2013-04-03

121

Thermodynamically Stable Pickering Emulsions  

NASA Astrophysics Data System (ADS)

We show that under appropriate conditions, mixtures of oil, water, and nanoparticles form thermodynamically stable oil-in-water emulsions with monodisperse droplet diameters in the range of 30 150 nm. This observation challenges current wisdom that so-called Pickering emulsions are at most metastable and points to a new class of mesoscopic equilibrium structures. Thermodynamic stability is demonstrated by the spontaneous evolution of binary droplet mixtures towards one intermediate size distribution. Equilibrium interfacial curvature due to an asymmetric charge distribution induced by adsorbed colloids explains the growth of emulsion droplets upon salt addition. Moreover, the existence of a minimal radius of curvature with a concomitant expulsion of excess oil is in close analogy with microemulsions.

Sacanna, S.; Kegel, W. K.; Philipse, A. P.

2007-04-01

122

Thermodynamically stable pickering emulsions.  

PubMed

We show that under appropriate conditions, mixtures of oil, water, and nanoparticles form thermodynamically stable oil-in-water emulsions with monodisperse droplet diameters in the range of 30-150 nm. This observation challenges current wisdom that so-called Pickering emulsions are at most metastable and points to a new class of mesoscopic equilibrium structures. Thermodynamic stability is demonstrated by the spontaneous evolution of binary droplet mixtures towards one intermediate size distribution. Equilibrium interfacial curvature due to an asymmetric charge distribution induced by adsorbed colloids explains the growth of emulsion droplets upon salt addition. Moreover, the existence of a minimal radius of curvature with a concomitant expulsion of excess oil is in close analogy with microemulsions. PMID:17501389

Sacanna, S; Kegel, W K; Philipse, A P

2007-04-12

123

Colloidal particles in emulsions  

Microsoft Academic Search

We propose a statistical mechanical model for colloidal particles suspended in an emulsion of liquid droplets. The particles are modeled as hard spheres. The interaction between droplets is also hard, but the particles are able to penetrate the droplets. A swelling of droplets is taken into account to ensure material conservation of the droplet liquid. Hence the presence of the

Francisco L. Román; Matthias Schmidt; Hartmut Löwen

2000-01-01

124

Polymerized Asphalt Emulsion.  

National Technical Information Service (NTIS)

It has been claimed that polymerized asphalt emulsion has outstanding characteristics of elasticity, adhesion, and cohesion which allows its use in seal coats in high speed, high volume roads, such as interstate highways. Another use would be on a lower c...

S. Q. Kidd

1990-01-01

125

Cellular Structure of Emulsions  

Microsoft Academic Search

THE letters and photographs published on this subject do not make it quite clear whether the cellular structure observed is confined to the surface, or exists in the interior of the emulsion. Superficial cellular structure is by no means uncommon, and is shown to advantage by thin layers of heavy tar-oil or benzaldehyde on the surface of water. If the

Chas. R. Darling

1914-01-01

126

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

NASA Astrophysics Data System (ADS)

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, N2 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.

Zhang, Ying; Jin, Chao

2011-01-01

127

Search for new states of matter with the STAR experiment at RHIC  

Microsoft Academic Search

High energy nucleus-nucleus collisions are used for the search for the Quark-Gluon Plasma, a state of matter predicted by lattice QCD. Since 1999, the STAR experiment recorded in total ⋍ 10 × 106Au + Au events at &surd;s=130 GeV and 200 GeV which were analyzed to determine the temperature, size and density of the collision system.

Jens Sören Lange

2003-01-01

128

Study on preparation and formation mechanism of n-alkanol/water emulsion using alpha-cyclodextrin.  

PubMed

Surfactants are usually used for the preparation of emulsions; however, some have an adverse effect on the human body such as skin irritation, hemolysis, and protein denaturation, etc. In this study, we examined the preparation and formation mechanism of n-alkanol/water emulsions using alpha-cyclodextrin (alpha-CD) as an emulsifier. Emulsions were prepared by mixing oil and water phases for 4 min at 2500 rpm using a vortex mixer. The mechanism of emulsification was investigated with some physico-chemical techniques. From phase diagrams of n-alkanol/alpha-CD/water systems, the emulsion phase extended as the chain length of n-alkanols and the amount of alpha-CD added increased. Furthermore, the emulsion was not formed in the region where the n-alkanol/alpha-CD complex didn't precipitate; however, the emulsion was formed in the region where the complex precipitated. In addition, it was clear that the emulsions have a yield stress value and correspond to the Maxwell model from rheological measurement. Our experiments clearly showed that the stable emulsions are formed because the precipitated complexes form a dense film at the oil-water interface and prevent aggregation among dispersed phases. Furthermore, it is suggested that the creation of a three-dimensional network structure formed by precipitated complexes in the continuous phase contributes to the stabilization of the emulsion. Thus, we concluded that the n-alkanol/water emulsions using alpha-cyclodextrin were a kind of the Pickering emulsion. PMID:17978523

Hashizaki, Kaname; Kageyama, Takashi; Inoue, Motoki; Taguchi, Hiroyuki; Ueda, Haruhisa; Saito, Yoshihiro

2007-11-01

129

Antioxidant properties of myricetin and quercetin in oil and emulsions  

Microsoft Academic Search

The effect of quercetin and myricetin on the stability of sunflower oil and oil-in-water emulsions was studied by storage\\u000a experiments monitored by measurement of peroxide values, conjugated dienes, and headspace volatile analysis. Myricetin showed\\u000a strong antioxidant activity in oils stored at 60 or 30°C and in oil-in-water emulsions stored at 30°C, whether tocopherols\\u000a or citric acid were present or not;

Andrea Roedig-Penman; Michael H. Gordon

1998-01-01

130

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)  

NASA Astrophysics Data System (ADS)

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.

Zayarnaya, I. S.

2008-02-01

131

Double Emulsion Templated Celloidosomes  

NASA Astrophysics Data System (ADS)

We present a novel approach for fabricating celloidosomes, which represent a hollow and spherical three-dimensional self-assembly of living cells encapsulating an aqueous core. Glass- capillary microfluidics is used to generate monodisperse water-in-oil-in-water double emulsion templates using lipids as stabilizers. Such templates allow for obtaining single but also double concentric celloidosomes. In addition, after a solvent removal step the double emulsion templates turn into monodisperse lipid vesicles, whose membrane spontaneously phase separates when choosing the adequate lipid composition, providing the adequate scaffold for fabricating Janus-celloidosomes. These structures may find applications in the development of bioreactors in which the synergistic effects of two different types of cells selectively adsorbed on one of the vesicle hemispheres may be exploited.

Arriaga, Laura R.; Marquez, Samantha M.; Kim, Shin-Hyun; Chang, Connie; Wilking, Jim; Monroy, Francisco; Marquez, Manuel; Weitz, David A.

2012-02-01

132

Aqueous rubberized coal tar emulsion  

SciTech Connect

An aqueous rubberized coal tar emulsion composition especially suitable for coating and sealing bituminous substrates containing asphalt such as asphalt pavement and the like, the coal tar emulsion composition comprising a major portion of commercial coal tar emulsion and water admixed with a small amount of a carboxylated butadiene/styrene/acid copolymer latex having a particular particle size. The emulsion composition may additionally include a fine aggregate filler material such as sand. The coal tar emulsion composition according to the invention is of a thixotropic nature and has the ability to maintain the fine aggregate when added and mixed therein in a homogeneous-like suspension. The emulsion composition when spread on an asphalt surface exhibits a high degree of spreadability and provides a sealing coating that has a long life.

Ladish, D.J.

1985-10-01

133

Multiple emulsions for food use  

Microsoft Academic Search

Numerous investigations were done to describe the effects of different food-grade components (e.g. lipid phases, emulsifiers, electrolytes, biopolymers, sugars) on the stability of multiple emulsions (type W\\/O\\/W and O\\/W\\/O). In addition to the emulsion composition, the stability of such systems also depends heavily on the emulsion matrix, influenced by the dispersing methods used. This review highlights recently published results of

Gerald Muschiolik

2007-01-01

134

Hadronic interactions at energies around 10/sup 3/ TeV inferred fromthe large-scale emulsion-chamber experiment at Mt. Fuji  

SciTech Connect

Details of experimental results, obtained with large-scale emulsion chambers at Mt. Fuji (3776 m above sea level), are presented. The experimental data, which is sensitive to hadronic interactions at energies around 10/sup 3/ TeV, is compared with Monte Carlo simulations based on various assumed interaction models and primary particles. The results may be briefly summarized as follows. (1) Scaling in the fragmentation region can be valid up to at least 10/sup 3/ TeV only if the primary particles are mixed with significant amounts of heavy nuclei at energies over 10/sup 14/ eV. (2) Cross sections should continue to increase with energy up to 10/sup 3/ TeV, at least, at almost the same rate as that obtained at lower energies. (3) There exists some evidence to indicate remarkable production of particles or jets with high P/sub t/ of several GeV/c at energies around 10/sup 3/ TeV. (4) Hadron-to-..gamma..-ray ratios in the observed family events remain almost within the scope of simulation prediction. Other interesting characteristics of family events are also discussed.

Akashi, M.; Amenomori, M.; Konishi, E.; Nanjo, H.; Watanabe, Z.; Mizutani, K.; Kasahara, K.; Torii, S.; Yuda, T.; Shirai, T.; Tateyama, N.; Taira, T.; Mito, I.; Shibata, M.; Sugimoto, H.; Taira, K.; Hotta, N.

1981-11-01

135

Cyclodextrin stabilised emulsions and cyclodextrinosomes.  

PubMed

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

Mathapa, Baghali G; Paunov, Vesselin N

2013-10-01

136

Geranyl acetate emulsions: surfactant association structures and emulsion inversion.  

PubMed

Three emulsions of geranyl acetate (GA)-in-water (W) with identical GA/W ratios and varying surfactant (S), Laureth 4, a commercial C(12)EO (4) compound, fractions were investigated for nature and stability. The emulsions with up to 6% surfactant were W/O, as expected with respect to the solubility of the surfactant in the oil. At 10% surfactant, the aqueous phase became the continuous one and the apparent stability of the emulsion was significantly enhanced. Analysis of the phase diagram and experimental evidence showed the high water content emulsion to be a liquid crystal-in-water emulsion; a kind that did not change even at extreme O/W and LC/W ratios. PMID:19409570

Friberg, Stig E; Al-Bawab, Abeer; Bozeya, Ayat; Aikens, Patricia A

2009-04-02

137

The compressed baryonic matter experiment at FAIR  

NASA Astrophysics Data System (ADS)

The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at high densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure both bulk observables with large acceptance and rare diagnostic probes such as charmed particles and vector mesons decaying into lepton pairs.

Senger, Peter

2012-12-01

138

Direct Current Electrorheological Stability Determination of Water-in-Crude Oil Emulsions  

NASA Astrophysics Data System (ADS)

Emulsion stability is a fundamental determination for separation technologies. We use the critical electric field (CEF) and viscosity changes in DC eletrorheological (ER) experiments in dynamic mode to determine the stability of water-in-crude oil emulsions, previously studied through bottle tests. The CEF value corresponds to the value of electric field at which the current reaches 95% or larger of the plateau value. The results show that CEF can be consistently obtained through current measurements, resulting from emulsion structure breakdown. Viscosity changes are not good proxies of stability unless a robust emulsion structure is found. Emulsion structure breakdown is explored through rheological characterization before and after voltage sweeps have been performed. When the electric field applied is below the CEF value, the storage and loss moduli responses as well as viscosity as functions of frequency are recovered. However, when the electric field is greater than the CEF value, the emulsion structure breaks down irreversibly.

Alvarado, Vladimir; Wang, Xiuyu

2009-11-01

139

A new method to correct deformations in emulsion using a precise photomask  

NASA Astrophysics Data System (ADS)

A new method to correct the emulsion deformation, mainly produced in the development process, is developed to recover the high accuracy of nuclear emulsion as a tracking device. The method is based on a precise photomask and a careful treatment of the emulsion films. A position measurement accuracy of 0.6?m is obtained over an area of 5 cm×7 cm. The method allows to measure positions of track segments with submicron accuracy in an ECC brick with as few as 10 reference tracks for alignment. Such a performance can be important for hybrid emulsion experiments at underground laboratories where only a small number of reference tracks for alignment are available.

Kimura, M.; Ishida, H.; Shibuya, H.; Ogawa, S.; Matsuo, T.; Fukushima, C.; Takahashi, G.; Kuge, K.; Sato, Y.; Tezuka, I.; Mikado, S.

2013-05-01

140

The factors affecting on Bitumen Emulsion properties  

Microsoft Academic Search

Need to proper roads and highways will increase with increasing automotive industry and development of cities and countries. Among petroleum products used in road construction and asphalt application for soil stability and adhesion between layers of asphalt are bitumen soluble and Bitumen Emulsions. Bitumen Emulsions are subset of water emulsion that in this type of emulsion dispersed phase is lipophilic

H. Kazemi Esfeh; B. Ghanavati; R. Shojaei Arani

2010-01-01

141

Formulation of shear rate sensitive multiple emulsions  

Microsoft Academic Search

This work mainly concentrates on the formulation of W\\/O\\/W multiple emulsions capable of breaking and releasing their inner aqueous phase under shear rates compatible with agroalimentary, pharmaceutical and cosmetic applications. Three kinds of multiple emulsions were studied: one with a high concentration of primary emulsion, not viscosified in the external aqueous phase; multiple emulsions gelified with a synthetic polymer (Carbopol

V Muguet; M Seiller; G Barratt; O Ozer; J. P Marty; J. L Grossiord

2001-01-01

142

Direct Current Electrorheological Stability Determination of Water-in-Crude Oil Emulsions  

Microsoft Academic Search

Emulsion stability is a fundamental determination for separation technologies. We use the critical electric field (CEF) and viscosity changes in DC eletrorheological (ER) experiments in dynamic mode to determine the stability of water-in-crude oil emulsions, previously studied through bottle tests. The CEF value corresponds to the value of electric field at which the current reaches 95% or larger of the

Vladimir Alvarado; Xiuyu Wang

2009-01-01

143

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

ERIC Educational Resources Information Center

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.

Mabrouk, Suzanne T.

2004-01-01

144

GAMMA-RAY INSENSITIVE EMULSIONS. Quarterly Report No. 8 for January 1, 1958March 31, 1958  

Microsoft Academic Search

Work on the possibility of recovering gammairradiated film for a ; subsequent light exposure was continued. This work covered the determination of ; the speed loss encountered as a function of the internal image density. Further ; experiments were carried out with an emulsion having a high-intensity reciprocity ; failure, in the hope that such an emulsion would be advantageous

D. A. Nepela; H. F. Nitka

1958-01-01

145

Double emulsions — scope, limitations and new achievements  

Microsoft Academic Search

Multiple emulsions are complex systems, termed “emulsions of emulsions”, i.e. the droplets of the dispersed phase contain even smaller dispersed droplets themselves. Each dispersed globule in the double emulsion is separated from the aqueous phase by a layer of oil-phase compartments.Double emulsions have significant potential in many applications since, at least in theory, they can serve as an entrapping reservoir

Nissim Garti

1997-01-01

146

Asphalt Emulsion Technology: Review of Asphalt Emulsion Residue Procedures. Transportation Research Circular E-C122.  

National Technical Information Service (NTIS)

Bituminous emulsion paving materials continue to be a challenging area of research and practical applications. Transportation Research Circular E-C102: Asphalt Emulsion Technology presented an overview of asphalt emulsion technology covering its chemistry...

2007-01-01

147

Modeling selected emulsions and double emulsions as memristive systems.  

PubMed

The recent development in basic and applied science and engineering of finely dispersed systems is presented in general, but more attention has been paid to the liquid-liquid finely dispersed systems or to the particular emulsions and double emulsions. The selected systems for theoretical and experimental research were emulsions and double emulsions that appeared in the pilot plant for extraction of uranium from wet phosphoric acid. The objective of this research was to try to provide a new or different approach to elaborate the complex phenomena that occur at developed liquid-liquid interfaces. New concepts were introduced, the first is a concept of an entity, and the corresponding classification of finely dispersed systems and the second concept consider the introduction of an almost forgotten basic electrodynamics element memristor, and the corresponding memristive systems. Based on these concepts a theory of electroviscoelasticity was proposed and experimentally corroborated using the selected representative liquid-liquid system. Also, it is shown that the droplet, and/or droplet-film structure, that is, selected emulsion and/or double emulsion may be considered as the particular example of memristive systems. PMID:22482789

Spasic, Aleksandar M; Jovanovic, Jovan M; Jovanovic, Mica

2012-03-21

148

Produced Fluid Emulsions. Final Report.  

National Technical Information Service (NTIS)

Emulsion production and stabilization may be due to one or more of several phenomenon including water-oil ratio, oil and brine chemistry, and surfactant and polymer type and concentration. They may influence emulsification either independently or with dep...

C. F. Hurley A. Himmelblau L. Trom

1984-01-01

149

Paraquat detoxication with multiple emulsions.  

PubMed

In this study, we show that detoxifying W/O/W multiple emulsions, prepared with an appropriate extractant/trapping couple, represent a promising technology for quick and safe poisoning treatments, with application to the highly toxic herbicide Paraquat, responsible of poisonings from low-dose exposure leading to several deaths every year. In vitro tests led to the choice of an appropriate extractant/trapping couple system with significant detoxication performance. In vivo tests showed (i) that rats receiving high doses of Paraquat, then a detoxifying emulsion, presented an increase from 50% to 100% of the MST (median survival time) and (ii) that no mortality was observed during 30 days with rats dosed with emulsions initially loaded with Paraquat at a concentration much higher than the lethal dose, proving the stability and the inocuity of the detoxifying multiple emulsion in the gastrointestinal tract. PMID:19635538

Frasca, S; Couvreur, P; Seiller, M; Pareau, D; Lacour, B; Stambouli, M; Grossiord, J L

2009-07-25

150

Emulsion breaking with surfactant recovery  

SciTech Connect

A process useful for recovering surfactant and oil of low water content in surfactant flood oil recovery projects is described. A produced oil-in-water emulsion is treated with brine and partitioning agent, preferably isopropyl alcohol, by mixing and settling to form 3 phases, an oil phase containing a minor amount of surfactant, a partitioning agent phase containing most of the surfactant originally present in the produced emulsion, and a brine phase containing a minor amount of alcohol. 13 claims.

Newcombe, J.

1980-08-05

151

Polysaccharide gel with multiple emulsion  

Microsoft Academic Search

The aim of the present work was to investigate the possibility of using a semicrystalline oil phase in W\\/O\\/W to modify the release of encapsulated hydrophilic compounds from polysaccharide gels with embedded multiple emulsions.l-Tryptophan was enclosed within the W1-phase of an W1\\/O\\/W2-emulsion, which itself was homogeneously distributed in a Ca2+-alginate gel with maltodextrin (D.E. 6.5) as a bulking agent. Various

Julia Weiss; Inta Scherze; Gerald Muschiolik

2005-01-01

152

Characterization of Surfactant Free Emulsions  

NASA Astrophysics Data System (ADS)

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.

Brar, Ramaninder; Urquidi, Jacob

2012-10-01

153

Testing of Fat Emulsions for Toxicity. III. Toxicity Studies with New Fat Emulsions and Emulsion Components.  

National Technical Information Service (NTIS)

Extensive studies were conducted at four separate laboratories to evaluate the chemical and physical properties, and the biological effects of two fat emulsions: Intralipid (20 per cent) and Lipofundin (15 per cent). In addition, a variety of experimental...

S. W. Thompson L. D. Jones J. F. Ferrell R. D. Hunt H. C. Meng

1965-01-01

154

Extending Temporary Storage Capacity Offshore with Emulsion Breakers.  

National Technical Information Service (NTIS)

The objective this study was to develop a more complete understanding of the use of emulsion breakers injected into an oil spill recovery system at both lab-scale (in Ottawa at SL Ross) and mid-scale (in New Jersey at Ohmsett). The experiments were design...

2002-01-01

155

Mechanism of supported liquid membrane degradation: emulsion formation  

Microsoft Academic Search

A new hypothesis for the degradation mechanism of supported liquid membranes is advanced: emulsion formation induced by shear forces. Experiments show that the removal of LM-phase from the membrane depends in the molecular structure of the carrier and the type of solvent. The instability of SLMs is regulated by the presence of counter-ions in the same way as in the

A. M. Neplenbroek; D. Bargeman; C. A. Smolders

1992-01-01

156

Lubricating Properties of Oil-In-Water Emulsions  

Microsoft Academic Search

Experiments are described in which elastohydrodynamic and boundary lubrication properties of O\\/W emulsions of mineral oil are studied with a variety of nonionic surfactants as the emulsifying agents. The changes in the minimum elastohydrodynamic film thickness are determined with different surfactants, with changes in oil concentration, with changes in emulsifying agent concentration, and with blending of different surfactants. These results

Yoshitsugu Kimura; Kazumi Okada

1989-01-01

157

Arrested of coalescence of emulsion droplets of arbitrary size  

NASA Astrophysics Data System (ADS)

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.

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

2013-03-01

158

Chemical Demulsification of Tanker Crude Emulsions.  

National Technical Information Service (NTIS)

The chemical demulsification of tanker crude emulsions was studied as a function of oil type (light vs. heavy crude), demulsifier concentrations, and temperature. Aerosol OT shows promise as a chemical demulsifier of tanker crude emulsions provided that a...

R. C. Little

1980-01-01

159

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

SciTech Connect

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.

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

1995-04-01

160

Double emulsions stabilized by macromolecular surfactants  

Microsoft Academic Search

Multiple emulsions are emulsions within emulsions, stabilized traditionally by monomeric emulsifiers both at the inner and outer interface.Double emulsions are thermodynamically unstable and fast coalescence, as well as fast release of markers and drugs, have been the main drawbacks of this technology.Polymeric synthetic emulsifiers, as well as natural macromolecules in combination with monomeric emulsifiers, have recently been studied and evaluated.The

Nissim Garti; Abraham Aserin

1996-01-01

161

Emulsions stabilised solely by colloidal particles  

Microsoft Academic Search

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.

Robert Aveyard; Bernard P Binks; John H Clint

2003-01-01

162

Well treatment with emulsion dispersions  

SciTech Connect

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 treatment applications including hydraulic fracturing and acidizing and can also be used to encapsulate or to transport well treatment materials and chemicals into the wellbore or formation. Treatment methods may also employ dispersions of a reactive simple or multiple emulsion. The distinct phases of the compositions may be selected to form treatment solutions upon mixing. Thus, improved acidizing may be achieved through an in situ reaction format.

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

1982-11-16

163

Asphalt-polyolefin emulsion breakdown  

Microsoft Academic Search

An analysis of factors controlling the stability of asphalt-polyolefin emulsions is given. From flocculation kinetics and changes in particle size distributions, it is concluded that the major cause of instability is due to Brownian coalescence followed by gravitational flocculation and creaming. A cyclical change in the particle size distribution, indicative of simultaneous flocculation and creaming, is observed only in the

S. A. M. Hesp; R. T. Woodhams

1991-01-01

164

Flocculation of Deformable Emulsion Droplets  

Microsoft Academic Search

The effect of different factors (drop radius, interfacial tension, Hamaker constant, electrolyte, micellar concentrations, etc.) on the interaction energy of emulsion droplets is studied theoretically. It is demonstrated that the deformation of the colliding droplets considerably affects the interaction energy. The contributions of the electrostatic, van der Waals, depletion, steric, and oscillatory surface forces, as well as of the surface

DIMITER N. PETSEV; NIKOLAI D. DENKOV; PETER A. KRALCHEVSKY

1995-01-01

165

Lipid oxidation in food emulsions  

Microsoft Academic Search

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

John N. Coupland; D. Julian McClements

1996-01-01

166

Inverted and multiple nematic emulsions  

Microsoft Academic Search

We investigate experimentally the structures that form when small colloidal particles are suspended in a nematic solvent. These structures are anisotropic, and their formation is driven by interactions arising from the orientational elasticity of the nematic solvent. By using inverted and multiple nematic emulsions composed of water droplets dispersed in a thermotropic liquid crystal, we identify the nature of these

P. Poulin; D. A. Weitz

1998-01-01

167

Treatment of coal tar emulsions  

Microsoft Academic Search

The present invention relates to a process for the treatment of stable emulsions of water and quinoline insolubles in coal tar comprising thoroughly mixing the coal tar with at least one of a specific class of surface-active compositions, followed by a separation of water and quinoline insoluble components from the mixture. The invention also relates to a method of eliminating

Cukier

1983-01-01

168

Neutron Spectra from Intermediate-Energy Nucleus-Nucleus Reactions  

SciTech Connect

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.

Iwase, Hiroshi [GSI, Planckstr. 1, 64291 Darmstadt (Germany); Iwata, Yoshiyuki [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Nakamura, Takashi [Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Gudima, Konstantin [Institute of Applied Physics, Academy of Science of Moldova, Chisinau, MD-2028 (Moldova, Republic of); Mashnik, Stepan; Sierk, Arnold; Prael, Richard [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2005-05-24

169

Effect of exchange on nucleus-nucleus interactions  

NASA Astrophysics Data System (ADS)

Based on the resonating group method theory, the potential between nuclei is evaluated by a new expansion, an orthonormalized particle-exchange-basis expansion. The present result is compared with the results of folding models, the fish-bone model, the usual particle-exchange expansions and the exact treatment in an ?+? system. A simplified model is presented and discussed in the ?+?, ?+16O, ?+40Ca, 16O+16O and 16O+40Ca systems.

Okabe, Shigeto

1983-08-01

170

Forward baryons in relativistic nucleus-nucleus collisions  

SciTech Connect

We present the rapidity and transverse momentum distributions of protons and neutrons from collisions between 14.6 GeV/nucleon beams of {sup 28}Si and targets of Al, Cu, and Pb. The data were measured in the forward spectrometer/target calorimeter detectors of the E814 apparatus. The results indicate the existence of two distinct domains, one of beam rapidity projectilelike nucleons, and the second of participant nucleons. From the former, the in-medium inelastic nucleon-nucleon cross section is deduced. It is found to agree, within 10%, with the free'' value of 30 mb although under present conditions one of the two colliding nucleons has been struck before with a high probability. We compare with the present data the predictions of a fragmentation model as well as of models dealing explicitly with the heavy-ion collision and particle creation and emission.

Barrette, J.; Bellwied, R.; Braun-Munzinger, P.; Cleland, W.E.; David, G.; Dee, J.; Fatyga, M.; Fox, D.; Greene, S.V.; Hall, J.; Hemmick, T.K.; Heifetz, R.; Herrmann, N.; Hogue, R.W.; Ingold, G.; Jayananda, K.; Kraus, D.; Shiva Kumar, B.; Lisa, M.; Lissauer, D.; Llope, W.J.; Ludlam, T.; Majka, R.; Makowiecki, D.; Mark, S.K.; Mitchell, J.T.; Muthuswamy, M.; O'Brien, E.; Polychronakos, V.; Pruneau, C.; Rotondo, F.; Sandweiss, J.; Simon, J.; Sonnadara, U.; Stachel, J.; Takai, H.; Throwe, T.; Waters, L.; Winter, C.; Woody, C.; Wolf, K.; Wolfe, D.; Zhang, Y. (McGill University, Montreal, H3A2T8 (Canada) State University of New York, Stony Brook, New York 11794 (United States) University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States) Brookhaven National Laboratory, Upton, New York 11973 (United States) Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States) Yale University, New Haven, Connecticut 06511 (United States) University of New Mexico, Albuquerque; (E814 Collaboration)

1992-02-01

171

High energy factorization in nucleus-nucleus collisions. I  

SciTech Connect

We derive a high energy factorization theorem for inclusive gluon production in A+A collisions. Our factorized formula resums (i) all-order leading logarithms (g{sup 2}ln(1/x{sub 1,2})){sup n} of the incoming parton momentum fractions, and (ii) all contributions (g{rho}{sub 1,2}){sup n} that are enhanced when the color charge densities in the two nuclei are of order of the inverse coupling--{rho}{sub 1,2}{approx}g{sup -1}. The resummed inclusive gluon spectrum can be expressed as a convolution of gauge invariant distributions W[{rho}{sub 1,2}] from each of the nuclei with the leading order gluon number operator. These distributions are shown to satisfy the JIMWLK equation describing the evolution of nuclear wave functions with rapidity. As a by-product, we demonstrate that the JIMWLK Hamiltonian can be derived entirely in terms of retarded light-cone Green's functions without any ambiguities in their pole prescriptions. We comment on the implications of our results for understanding the Glasma produced at early times in A+A collisions at collider energies.

Gelis, Francois [Theory Division, PH-TH, Case C01600, CERN, CH-1211, Geneva 23 (Switzerland); Lappi, Tuomas [Institut de Physique Theorique (URA 2306 du CNRS) CEA/DSM/Saclay, Batiment 774 91191, Gif-sur-Yvette Cedex (France); Venugopalan, Raju [Physics Department, Brookhaven National Laboratory Upton, New York 11973 (United States)

2008-09-01

172

Multifragment Disintegrations in Intermediate Energy Nucleus-Nucleus Collisions.  

NASA Astrophysics Data System (ADS)

The possibility for the highly excited nuclear matter to break into multi-fragment final states has been predicted by various theoretical calculations. Experimental information about low-density nuclear equation of state may be obtainable from detailed studies of multi-fragment emission processes. A new low-threshold 4pi charged particle detector array, the MSU Miniball, has been constructed for the study of multi-fragmentation. Intermediate mass fragment (IMF) emission has been studied using beams of ^{14}N at E/A = 50 MeV and ^{36}Ar at E/A = 20, 35 MeV on ^{238}U and ^{197}Au targets. Most IMFs are emitted in central collisions characterized by large charged-particle multiplicities. Energy spectra and angular distributions indicate the non-equilibrium nature of IMF emission. Time-scales of multi-fragment emission, key in distinguishing the various reaction mechanisms, have been studied using two-fragment correlation functions. The experimental two-fragment correlation functions were found to depend mainly on the reduced relative velocity, rm v_{red} = v_{rel}/ sqrt{Z_1 + Z_2}, of the fragment pairs. It is therefore possible to sum over different pair combinations with little loss in resolution. From the comparisons of the inclusive experimental correlation functions with the classical expression of Koonin-Pratt formula, mean emission times of the order of 100-200 fm/c have been extracted with about 50% uncertainty. Three -body Coulomb trajectory calculations were also performed to estimate the uncertainty from the interaction with the heavy residue. A more detailed study indicates that fragment emission in central collisions begins at the very early stages of the reaction and continues throughout the later equilibrated stages.

Kim, Yeongduk

173

Random close packing of polydisperse jammed emulsions  

NASA Astrophysics Data System (ADS)

Packing problems are everywhere, ranging from oil extraction through porous rocks to grain storage in silos and the compaction of pharmaceutical powders into tablets. At a given density, particulate systems pack into a mechanically stable and amorphous jammed state. Theoretical frameworks have proposed a connection between this jammed state and the glass transition, a thermodynamics of jamming, as well as geometric modeling of random packings. Nevertheless, a simple underlying mechanism for the random assembly of athermal particles, analogous to crystalline ordering, remains unknown. Here we use 3D measurements of polydisperse packings of emulsion droplets to build a simple statistical model in which the complexity of the global packing is distilled into a local stochastic process. From the perspective of a single particle the packing problem is reduced to the random formation of nearest neighbors, followed by a choice of contacts among them. The two key parameters in the model, the available space around a particle and the ratio of contacts to neighbors, are directly obtained from experiments. Remarkably, we demonstrate that this ``granocentric'' view captures the properties of the polydisperse emulsion packing, ranging from the microscopic distributions of nearest neighbors and contacts to local density fluctuations and all the way to the global packing density. Further applications to monodisperse and bidisperse systems quantitatively agree with previously measured trends in global density. This model therefore reveals a general principle of organization for random packing and lays the foundations for a theory of jammed matter.

Brujic, Jasna

2010-03-01

174

Improved controlled temperature and relative humidity DMA of artists’ acrylic emulsion paint films  

Microsoft Academic Search

Issues encountered with dynamic mechanical analysis of artists’ acrylic emulsion paint films are presented alongside modifications\\u000a to improve controlled relative humidity (RH) experiments using isothermal and thermal scanning conditions. Free films of titanium\\u000a white (PW6) artists’ acrylic emulsion paints were cast as free films and their viscoelastic properties measured using the\\u000a tensile mode of the dynamic mechanical analyser (DMA). Artists’

B. Ormsby; G. Foster; T. Learner; S. Ritchie; M. Schilling

2007-01-01

175

Effect of fibrous filter properties on the oil-in-water-emulsion separation and filtration performance  

Microsoft Academic Search

Separation of secondary emulsions of dispersed droplet size less than 10?m, by means of fibrous medium is a very complex but important process. The study investigates the influence of thin fibrous filter properties, i.e. surface energy, pore size and porosity on the separation performance of an isooctane in water emulsion (0.2%, mean drop size 2?m). Experiments were carried out on

Swarna Bansal; Volkmar von Arnim; Thomas Stegmaier; Heinrich Planck

2011-01-01

176

Oil–acrylate hybrid emulsions, mini-emulsion polymerization and characterization  

Microsoft Academic Search

The use of oxidized triglycerides as initiators for the mini-emulsion polymerization of acrylate is described. Unsaturated triglycerides, as in, e.g. sunflower, were treated with molecular oxygen to generate fatty-acid hydroperoxide groups. Oil–acrylate hybrid emulsions were formed using the fatty-acid hydroperoxides as initiators for the mini-emulsion polymerization of acrylates in an Fe2+\\/EDTA\\/SFS redox system. The mini-emulsion system was established with n-hexadecane

Eelco M. S van Hamersveld; J. J. G. S van Es; F. P Cuperus

1999-01-01

177

Salt stability of casein emulsions  

Microsoft Academic Search

We present a comparison of the salt stability of oil-in-water emulsions prepared separately with ?author-casein, ?-casein and sodium caseinate at low protein\\/oil ratios. Measurements have been made of changes in average droplet sizes, creaming rates, and bulk and interfacial rheology over the pH range 5.5–7.0 and ionic strength range 0.01–0.20 M. Static light-scattering has also been used to determine second

Eric Dickinson; Maria G. Semenova; Anna S. Antipova

1998-01-01

178

Drying of alkyd emulsion paints  

Microsoft Academic Search

The drying and film formation of long oil alkyd emulsions was investigated with emphasis on loss of dry upon storage. The\\u000a main reason for loss of dry was adsorption of the cobalt (drier) on pigment surfaces as a precipitated hydroxide. Titanium\\u000a dioxides with alumina surface treatment and organic pigments were most detrimental to drying. Acrylate- and phosphate-based\\u000a dispersants also deactivated

P. K. Weissenborn; A. Motiejauskaite

2000-01-01

179

Demulsification of bitumen emulsions using ionenes  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/W) emulsions is disclosed wherein water-soluble demulsifiers are used. These demulsifiers are ionenes prepared generally by reaction of ditertiary amines and dihalides. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/C wherein the demulsifier of the invention is contacted with the bituminous emulsion.

McCoy, D.R.; McEntire, E.E.

1983-09-13

180

Demulsification of bitumen emulsions using cationic polymers  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/w) emulsions is disclosed wherein water soluble demulsifiers are used. These demulsifiers are cationic polymers of equal to or greater than about 2,000 molecular weight obtained by the reaction of polyalkoxydiamines with epihalohydrins. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/ C wherein the demulsifier of the invention is contacted with the bituminous emulsion.

Mccoy, D.R.; Young, K.B.

1983-05-10

181

Demulsification of bitumen emulsions using polyureas  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/w) emulsions is disclosed wherein water soluble demulsifiers are used. These demulsifiers are polyureas of average molecular weight greater than about 5,000 prepared by the reaction between a polyisocyanate and a polyoxyalkylenediamine. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/ C wherein the demulsifier of the invention is contacted with the bituminous emulsion.

Mccoy, D.R.; Young, K.B.

1983-05-24

182

Controlled generation of double emulsions in air.  

PubMed

This Letter describes the controlled generation of double emulsions in the gas phase, which was carried out using an integrated emitter in a poly(dimethylsiloxane) (PDMS) 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

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

2013-06-14

183

Aligned Events Observed by Emulsion Chambers in the Knee Region  

NASA Astrophysics Data System (ADS)

The coplanar emission of very high energy secondary cosmic rays was observed at stratospheric altitudes by the X-ray emulsion chamber experiments ECHOS-Concorde and RUNJOB. This paper treats the physical relevancy of the experimental observations using Monte Carlo calculations carried out with the help of the CORSIKA program. Different high energy hadronic interaction models have been used to study the possible dependence of this effect upon the primary particle mass number.

Talai, M. C.; Attallah, R.; Capdevielle, J. N.

184

Evaluating factors affecting the permeability of emulsions used to stabilize radioactive contamination from a radiological dispersal device.  

PubMed

Present strategies for alleviating radioactive contamination from a radiological dispersal device (RDD) or dirty bomb involve either demolishing and removing radioactive surfaces or abandoning portions of the area near the release point. In both cases, it is imperative to eliminate or reduce migration of the radioisotopes until the cleanup is complete or until the radiation has decayed back to acceptable levels. This research investigated an alternative strategy of using emulsions to stabilize radioactive particulate contamination. Emergency response personnel would coat surfaces with emulsions consisting of asphalt or tall oil pitch to prevent migration of contamination. The site can then be evaluated and cleaned up as needed. In order for this approach to be effective, the treatment must eliminate migration of the radioactive agents in the terror device. Water application is an environmental condition that could promote migration into the external environment. This research investigated the potential for water, and correspondingly contaminant, migration through two emulsions consisting of Topein, a resinous byproduct during paper manufacture. Topein C is an asphaltic-based emulsion and Topein S is a tall oil pitch, nonionic emulsion. Experiments included water adsorption/ mobilization studies, filtration tests, and image analysis of photomicrographs from an environmental scanning electron microscope (ESEM) and a stereomicroscope. Both emulsions were effective at reducing water migration. Conductivity estimates were on the order of 10(-80) cm s(-1) for Topein C and 10(-7) cm s(-1) for Topein S. Water mobility depended on emulsion flocculation and coalescence time. Photomicrographs indicate that Topein S consisted of greater and more interconnected porosity. Dilute foams of isolated spherical gas cells formed when emulsions were applied to basic surfaces. Gas cells rose to the surface and ruptured, leaving void spaces that penetrated throughout the emulsion. These experiments indicate that emulsions may be a viable means for containing RDD residuals; however, improvements are needed for optimal performance. PMID:15952383

Fox, Garey A; Medina, Victor F

2005-05-15

185

Rheological and dielectric behavior of electrorheological emulsions  

Microsoft Academic Search

The rheological and dielectric behavior of electrorheological (ER) emulsions composed of silicone oil (continuous phase) and two chlorinated paraffins (dispersed phase) are studied in this work. The chlorinated paraffins have different permittivity and conductivity values, and both are more conducting than the silicone oil. The rheological behavior of the emulsions is analyzed under constant dc electric fields, for two chlorinated

L Rejon; B Ortiz-Aguilar; H de Alba; O Manero

2004-01-01

186

YIELD STRESS DETERMINATION OF ASPHALT EMULSIONS  

Microsoft Academic Search

The yield stress of asphalt emulsions was investigated as a potential quality control parameter. Viscometric data were determined using concentric cylinder, parallel plate, and cone and plate geometries. The use of a novel slotted-plate technique was investigated to determine the yield stress of asphalt emulsions in a direct way, that is to say, without extrapolation. The Saybolt viscosity was determined

Max Hetzer; Kyle Frederic; Daniel De Kee; Christopher D. Abadie

2007-01-01

187

Treatment of oil-in-water emulsions  

SciTech Connect

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.

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

1980-01-08

188

Perfluorochemical emulsions can increase tumor radiosensitivity  

Microsoft Academic Search

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.

B. A. Teicher; C. M. Rose

1984-01-01

189

Optimization of cell-wall skeleton derived from Mycobacterium bovis BCG Tokyo 172 (SMP-105) emulsion in delayed-type hypersensitivity and antitumor models.  

PubMed

Cell-wall skeleton prepared from Mycobacterium bovis BCG (BCG-CWS) is known as a potent adjuvant and has been shown to possess antitumor activity in many non-clinical and clinical studies. As there are no approved BCG-CWS formulations for cancer therapy, we investigated the potential for cancer immunotherapy of SMP-105, our originally produced BCG-CWS. For optimizing SMP-105 emulsion, we compared the effects of drakeoland squalane-based SMP-105 emulsions on IFN-? production in rats and evaluated their ability to induce skin reaction in guinea pigs. Both emulsions had the same activity in both experiments. We selected squalane as base material and produced two types of squalane-based formulations (vialed emulsion and pumped emulsion) that can easily be prepared as oil-in-water emulsions. Although the vialed emulsion showed the same pattern of distribution as a usual homogenized emulsion, the pumped emulsion showed more uniform distribution than the other two emulsions. Whereas both emulsions enhanced strong delayed type hypersensitivity (DTH) reaction in a mouse model, the pumped emulsion induced slightly smaller edema. Data on oil droplet size distribution suggest that few micrometer oil droplet size might be appropriate for oil-in-water microemulsion of SMP-105. The antitumor potency of SMP-105 emulsion was stronger than that of some of the launched toll-like receptor (TLR) agonists (Aldara cream, Picibanil, and Immunobladder). Aldara and Picibanil showed limited antitumor effectiveness, while Immunobladder had almost the same effect as SMP-105 at the highest dose, but needed about 10 times the amount of SMP-105. These findings first indicate that SMP-105 has great potential in cancer immunotherapy. PMID:23006993

Miyauchi, M; Murata, M; Fukushima, A; Sato, T; Nakagawa, M; Fujii, T; Koseki, N; Chiba, N; Kashiwazaki, Y

2012-08-01

190

Emulsion based cast booster - a priming system  

SciTech Connect

This paper explores the potential of emulsion based cast booster to be used as primer to initiate bulk delivered emulsion explosives used in mines. An attempt has been made for comparative study between conventional cast booster and emulsion based cast booster in terms of the initiation process developed and their capability to develop and maintain the stable detonation process in the column explosives. The study has been conducted using a continuous velocity of detonation (VOD) measuring instrument. During this study three blasts have been monitored. In each blast two holes have been selected for study, the first hole being initiated with conventional cast booster while the other one with emulsion based cast booster. The findings of the study advocates that emulsion based cast booster is capable of efficient priming of bulk delivered column explosive with stable detonation process in the column. Further, the booster had advantages over the conventional PETN/TNT based cast booster. 5 refs., 2 figs., 1 tab., 1 photo.

Gupta, R.N.; Mishra, A.K. [National Institute of Rock Mechanics, KGF (India)

2005-07-01

191

Oleophilic separation of inverse emulsions  

SciTech Connect

The oleophilic sieve is a patented device for separating mixtures of oil phase and aqueous phase wherein the aqueous phase passes through the sieve apertures and the oil phase is captured by the sieve surfaces upon contact. This method achieves very efficient separations and is not adversely affected by solids in the aqueous phase or by the density of the oil phase. Normally the mixture is agglomerated during the separation process to increase the oil phase particle size and to permit it to be more readily captured by the sieve. The oleophilic sieve may be used to separate a large variety of mixtures and has been tested with mined tar sand slurries, middlings, tailings, tailings pond sludge and inverse emulsions produced from in-situ steam drive facilities. For emulsions, a demulsifier is normally required but no diluent is used to recover the bitumen or heavy oil from the aqueous phase. This results in high bitumen recovery, clean water effluents and minimizes overall separation costs.

Kruyer, J.

1984-02-01

192

Monodisperse Double Emulsions Generated from a Microcapillary Device  

Microsoft Academic Search

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

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

2005-01-01

193

Synthesis and characterization of palm oil alkyd emulsions  

Microsoft Academic Search

This paper describes the preparation of palm oil alkyd emulsions. The palm oil alkyds were first synthesized by fusion cooks by using palm kernel oil (PKO), phthalic anhydride (PA) and glycerol (Gly). The resulting alkyds were then converted into emulsions through emulsion inversion point (EIP) method by adding water and surfactants. These emulsions could be blended with natural rubber (NR)

Lee Siang Yin; Gan Seng Neon

194

Future Experiments with HADES at FAIR  

NASA Astrophysics Data System (ADS)

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.

Tlustý, P.

2010-12-01

195

The compressed baryonic matter experiment at FAIR  

NASA Astrophysics Data System (ADS)

The compressed baryonic matter (CBM) experiment will be one of the major scientific activities at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high-baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at high densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure both bulk observables with large acceptance and rare diagnostic probes such as charmed particles and vector mesons decaying into lepton pairs. The layout and the physics performance of the proposed CBM experimental facility will be discussed.

Senger, P.; Galatyuk, T.; Kiseleva, A.; Kresan, D.; Lebedev, A.; Lebedev, S.; Lymanets, A.

2009-06-01

196

The Compressed Baryonic Matter experiment at FAIR  

NASA Astrophysics Data System (ADS)

The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at high densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure both bulk observables with large acceptance and rare diagnostic probes such as charmed particles and vector mesons decaying into lepton pairs. The layout and the physics performance of the proposed CBM experimental facility will be discussed.

Senger, P.

2011-07-01

197

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

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

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

2010-01-01

198

Particle multiplicity and energy flow in central sulphur interactions at 200 GeV per nucleon in emulsion  

NASA Astrophysics Data System (ADS)

Central interactions of sulphur ions at 200 GeV per nucleon in emulsion and tungsten targets were selected by transverse energy and multiplicity in the framework of the NA34 (HELIOS) experiment at CERN. A detailed study of charged-particle multiplicity in emulsion and of the energy flow in the fine-grained HELIOS calorimeters is presented for updated event samples. Taking advantage of the wide angular coverage of both the emulsion and the calorimeters, systematic trends of the transverse energy per charged particle are investigated in various rapidity bins, ranging from the target region to the projectile region.

Liberto, Sergio Di

1991-04-01

199

Multiple emulsions controlled by stimuli-responsive polymers.  

PubMed

The phase inversion of water-toluene emulsions stabilized with a single thermo- and pH-sensitive copolymer occurs through the formation of multiple emulsions. At low pH and ambient temperature, oil in water emulsions are formed which transform into highly stable multiple emulsions at pHs immediately lower than the inversion border. At higher pHs, the emulsion turns into a water in oil one. PMID:23483699

Besnard, Lucie; Marchal, Frédéric; Paredes, Jose F; Daillant, Jean; Pantoustier, Nadège; Perrin, Patrick; Guenoun, Patrick

2013-03-11

200

Method for the resolution of enhanced oil recovery emulsions  

SciTech Connect

An oil-in-water emulsion of crude oil, water and hydrophilic surfactant is resolved by first heating said emulsion until it separates into a surfactant laden water layer and an oil-rich emulsion layer, removing the water layer from the oil-rich emulsion layer, treating the emulsion layer by the addition of from 20 to 40 volume percent of water containing a demulsifier and recovering the crude oil which separates from the water upon standing.

Shaw, D.L.

1984-04-24

201

Nonideal detonation of Al-rich emulsion explosives  

NASA Astrophysics Data System (ADS)

It is known that emulsion explosives behave non-ideally in their detonation. The behavior of the non-ideal detonation has not yet been sufficiently investigated. In order to obtain a better comprehension of the non-ideal detonation behavior, optical measurements and measurements of the velocity of the detonation wave were carried out. Streak photographs were taken by an image converter camera using a usual shadowgraph system. Five kinds of emulsion explosives which differ the aluminum contents were used in experiments. These emulsion explosives were put into copper, aluminum and PMMA containers. In case of the copper pipe container, the velocity of the detonation wave is constant at any aluminum contents. But in the case of the PMMA pipe container, the velocity of the detonation wave becomes lower in proportion to aluminum contents. The shapes of the reaction zone and the front of the detonation zone were also recognized from the streak photographs. In case of the copper pipe container, the detonation wave is plane, but in case of PMMA pipe container, the detonation wave curves near the pipe wall and its shape is a convex. It is considered that acoustic impedance of the container have effects on the propagation of the detonation wave.

Itoh, Shigeru; Takahashi, Katsuhiko; Murata, Kenji; Katoh, Yukio; Kira, Akio; Kojima, Masaki; Fujita, Masahiro

1997-12-01

202

Nonideal detonation of Al-rich emulsion explosives  

NASA Astrophysics Data System (ADS)

It is known that emulsion explosives have non-ideally in their detonation. The behavior of the non-ideal detonation has not yet been sufficiently investigated. In order to obtain a better comprehension of the non-ideal detonation behavior, optical measurements and measurements of the velocity of the detonation wave were carried out. Streak photographs were taken by an image converter camera using an usual shadowgraph system. Five kinds of emulsion explosives which differ the aluminum contents were used in experiments. These emulsion explosives were put into a copper, an aluminum and a PMMA containers. In case of the copper pipe container, the velocity of the detonation wave is constant at any aluminum contents. But in case of the PMMA pipe container, the velocity of the detonation wave becomes lower in proportion to aluminum contents. The shapes of the reaction zone and the front of the detonation zone were also recognized from the streak photographs. In case of the copper pipe container, the detonation wave is plane, but in case of PMMA pipe container, the detonation wave curves near the pipe wall and its shape is a convex. It is considered that acoustic impedance of the container have effects on the propagation of the detonation wave.

Itoh, Shigeru; Takahashi, Katsuhiko; Murata, Kenji; Katoh, Yukio; Kira, Akio; Kojima, Masaki; Fujita, Masahiro

1997-05-01

203

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

Code of Federal Regulations, 2010 CFR

...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....

2009-01-01

204

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

Code of Federal Regulations, 2010 CFR

...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....

2010-07-01

205

Method for demulsification of bitumen emulsions  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/W) emulsions is disclosed wherein water soluble demulsifiers are used. These demulsifiers are polymers of specific quaternary ammonium monomers or co-polymers of these quaternary ammonium monomers wth other types of monomers wherein the greater portion of the co-polymer is comprised of the quaternary ammonium monomers. To resolve the bitumonous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/ C. wherein the demulsifier of the invention is contacted with the bituminous emulsion.

McCoy, D.R.; Entire, E.E.; Gipson, R.M.

1984-07-03

206

Polylactide Microparticles Prepared by Double Emulsion\\/Evaporation Technique. I. Effect of Primary Emulsion Stability  

Microsoft Academic Search

The process of microencapsulation of proteins by double emulsion\\/evaporation in a matrix of polylactide (PLA) can be divided into three successive steps: first, an aqueous solution of the active compound is emulsified into an organic solution of the hydrophobic coating polymer; second, this primary water-in-oil emulsion (w\\/o) is dispersed in water with formation of a double water-oil-water emulsion (w\\/o\\/w); third,

Nicole Nihant; Chantal Schugens; Christian Grandfils; Robert Jérôme; Philippe Teyssié

1994-01-01

207

Performance-Related Test for Asphalt Emulsions.  

National Technical Information Service (NTIS)

Yield stress was investigated as a potential quality control parameter for asphalt emulsions. Viscometric data were determined using the concentric cylinder, parallel plate, and cone and plate geometries with rotational rheometers. We also investigated th...

D. D. Kee C. D. Abadie M. Hetzer K. Frederic

2004-01-01

208

Asphalt Emulsion Slurry Seals Modified with Additives.  

National Technical Information Service (NTIS)

Eighteen different materials, including 14 water emulsions, three sizes of ground rubber tread, and portland cement, were tested as additives to a standard slurry seal formulation. Most of the additives increased the cohesive strength, the resistance to a...

R. W. Drisko

1973-01-01

209

Batch extraction of gold(III) ions from aqueous solutions using emulsion liquid membrane via facilitated carrier transport  

Microsoft Academic Search

Experimental results for the batch extraction of gold(III) ions using an emulsion liquid membrane (ELM) with an internal alkaline aqueous sodium sulfite are presented. Experiments were performed using LK-80 as the biodegradable emulsifier for the first time in emulsion liquid membrane technology. The effects of various parameters, such as Au(III) concentration in the aqueous phase, concentration of carrier in the

Ali Kargari; Tahereh Kaghazchi; Morteza Sohrabi; Mansoureh Soleimani

2004-01-01

210

Emulsifier for water-in-oil emulsions  

SciTech Connect

This patent describes a water-in-oil emulsion. It comprises: a continuous oil phase, a discontinuous aqueous phase, and an emulsion stabilizing amount of a thermally altered lecithin composition which has been prepare by heating lecithin at a temperature in the range of from about 100{degrees}C, to about 250{degrees}C, for a period of time ranging from about 15 to about 480 minutes.

Weete, J.D.; Griffith, G.L.

1990-07-24

211

On the clearing of emulsion plates  

Microsoft Academic Search

Summary  The effect of the addition of Ammonium Chloride, Ammonium Hydroxide, and Ammonium Sulphocyanide to the Hypo bath of different\\u000a concentrations, on the clearing time of thin and thick emulsions (up to 1000 ?m) has been observed. In the case of thin emulsions\\u000a no rise for higher concentrations has been found. A detailed study of the three baths, for different concentrations

Y. Prakash; N. Ahamad; A. P. Sharma

1958-01-01

212

Fluorocarbon emulsions--the stability issue.  

PubMed

Long-term room temperature stability of ready-to-use concentrated fluorocarbon emulsions is necessary in order to fully exploit the therapeutic potential of fluorocarbons. Consequently, considerable efforts have been directed at investigating the physical nature of such emulsions, the mechanisms which lead to their degradation and the means of counteracting these. The particles which constitute typical fluorocarbon/egg yolk phospholipid emulsions have been identified to be surfactant-coated fluorocarbon droplets and lipid vesicles. Better understanding has been gained on the formation, structure and evolution of these particles during processing and storage. This has led to optimized formulations and processing, better control of emulsion characteristics and significantly improved stability. Molecular diffusion (Ostwald ripening or transcondensation) has been shown to be the maun mechanism of degradation when particles are less than 1 micron in diameter, even for the highly concentrated (volume fraction of fluorocarbon up to 50%) second generation fluorocarbon emulsions. Significant emulsion stabilization has been accomplished by adding fluorochemicals which are both less volatile and less water soluble, and nevertheless have an organ dwell time acceptable for intravascular use. The rate of molecular diffusion can also be reduced by decreasing the fluorocarbon/water interfacial tension; this was effectively achieved with appropriate, well-defined fluorinated surfactants. A further, novel means of stabilizing fluorocarbon-in-water emulsions makes use of mixed fluorocarbon-hydrocarbon amphiphiles which act as molecular dowels to reinforce the adhesion between the fluorocarbon phase and the lipophilic zone of the surfactant film. Both long-term room temperature stability, and particle-size control over a large range of diameter, have been achieved by applying this principle. All in all it can be said that the challenge of producing injectable fluorocarbon emulsions with long-term room temperature particle size stability has been met. PMID:7849970

Postel, M; Riess, J G; Weers, J G

1994-01-01

213

Applied Statistics: Crude Oil Emulsions and Demulsifiers  

Microsoft Academic Search

Water?in?crude oil emulsions are encountered at many oilfield production facilities. These emulsions are often inherently stable requiring the use of chemical treatment, heat, and residence time to effect resolution. The addition of chemical demulsifiers in small levels can greatly facilitate oil–water separation. Even with numerous demulsifier applications in place throughout the world, there still remains a great deal to understand

Michael K. Poindexter; Paul M. Lindemuth

2004-01-01

214

Microgel-stabilized smart emulsions for biocatalysis.  

PubMed

Emulsions stabilized by stimuli-responsive microgels were used to perform enzyme catalysis. Many substrates are poorly water-soluble, while enzymes naturally require aqueous environments, thus resulting in a two-phase aqueous-organic system. Smart microgels allow an enzyme-catalyzed reaction to be performed in an emulsion that can be broken under controlled conditions to separate the reaction product and to recycle the enzyme (E) and the microgel. PMID:23184415

Wiese, Susanne; Spiess, Antje C; Richtering, Walter

2012-11-26

215

FORMATION AND APPLICATIONS OF MULTIPLE EMULSIONS  

Microsoft Academic Search

Multiple emulsions, especially water-in-oil-in-water (W\\/O\\/W) type systems, have potential applications for the formulation and processing of foods, drugs, cosmetics, etc, as each dispersed globule in this type of emulsions consists of liquid compartments separated from the same liquid suspending medium by a thin layer of another immiscible liquid components. This article reviews a series of fundamental works on the formation

S. Mataumoto; W. W. Kang

1989-01-01

216

Double emulsions: how does release occur?  

Microsoft Academic Search

Water-in-oil-in-water double emulsions (W\\/O\\/W) consist of dispersed oil globules containing smaller aqueous droplets. These materials offer interesting possibilities for the controlled release of chemical species initially entrapped in the internal droplets. A better understanding of the stability conditions and release properties in double emulsions requires the use of model systems with a well-defined droplet size. In this paper, we use

K Pays; J. Giermanska-kahn; B. Pouligny; J. Bibette; F. Leal-calderon

2002-01-01

217

FRAGRANCE EMULSIONS STABILIZED BY A TRIBLOCK COPOLYMER  

Microsoft Academic Search

The phase diagram was determined of the system a fragrance oil, phenethyl alcohol, a commercial triblock copolymer, PE\\/L101, and water. The stability of emulsions containing 95 wt% water and various amounts of the fragrance and polymer was investigated both visually and with the aid of an optical microscope. The stability of the two-phase emulsions was explained through the interfacial behavior

Zhiqiang Zhang; Jennifer L. Barber; Stig E. Friberg; Patricia A. Aikens

2000-01-01

218

Emulsion and Accumulation at Aqueous/Organic Interface of Mixer-Settlers.  

National Technical Information Service (NTIS)

The emulsion which results from Di-n-butylphosphoric acid (HDBP) and zirconium (HDBP-Zr emulsion) was studied on the formation ratio to the emulsion of nonsoluble fission product residues (nonsoluble residues emulsion) in the codecontamination cycle witho...

K. Gonda S. Yasu K. Oka

1984-01-01

219

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

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

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

2013-01-01

220

Transport in two dimensional electronic micro-emulsions  

SciTech Connect

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.

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

221

Simple and Double Emulsions via Coaxial Jet Electrosprays  

NASA Astrophysics Data System (ADS)

We report for the first time the generation of electrified coaxial jets of micrometric diameter in liquid media. Scaling laws to predict the inner and outer diameter of the coaxial jet are given. We show some experiments illustrating the formation process of the coaxial jet, and demonstrate how this process can be used to yield either o/w (oil in water) or o/w/o (oil/water/oil) emulsions of micrometric size. Some interesting analogies with other hydrodynamic focusing processes are also pointed out.

Marín, Álvaro G.; Loscertales, Ignacio G.; Márquez, M.; Barrero, A.

2007-01-01

222

Emulsions stability, from dilute to dense emulsions -- role of drops deformation.  

PubMed

The present paper starts with a review of fundamental descriptions based on physico-chemical laws derived for emulsions with a special interest for eventual evidences of drops deformation. A critical analysis of theories and experiments is given that leads the authors to propose new static and dynamic models for the approach to flocculation and coalescence of two deformable drops in dense and dilute environments of other neighboring drops. The model developed is based on an old paper by Albers and Overbeek for W/O dense emulsions with non-deformable particles, that has been improved recently first by Sengupta and Papadopoulos and then by Mishchuk et al. to account for all the interaction forces (electrostatic, van der Waals and steric). The basic idea here rests in the assumption that the flat surface area of the two coalescing drops, interacting in the field of other particles, increases when the distance between the particles decreases according to an exponential law with a characteristic length related to the disjoining force in the inter-particle film and to the capillary pressure that opposes flattening. The difficulty lies, indeed, in manifold interpretations on experimental observations so that no clear conclusion can be derived on mechanisms responsible for the deformation of droplets. This is why, from a pure theoretical and physical point of view, according to rather complicated models, we propose a much more simple approach that permits to define a capillary length as part of virtual operations. In a static approach, this length is based on analogy with electricity, namely repulsion leads to flatness while attraction to hump. Therefore this brings us to a definition of a length depending on the maximum value of the disjoining pressure in competition with the capillary pressure. Gravity also promotes flocculation, therefore we compare the maximum values of the surface forces acting between the surfaces of two floculating particles to gravity. Finally, considering that in most publications on emulsions foams and colloidal systems, much attention is paid on the role of the drainage in the stability process, we devote the last section to the drainage between flattened drops. We first describe briefly Taylor's approach and extend Reynolds revisited formulae taking into account the viscous friction, the disjoining pressure, the film elasticity and the wetting angle weighting the capillary pressure through the characteristic length. Our calculated values are compared to some experimental data. In conclusion to make this long paper as useful as possible for research purposes, we have the hope that our understanding of emulsion stability is not only based on knowledge of numerous theoretical and experimental works sometimes controversial given in a critical way but that it gives a new approach based on an interpretation of the drop deformation in terms of a characteristic length linked to a deformation number analogous to a Bond number. PMID:18313631

Sanfeld, Albert; Steinchen, Annie

2008-01-11

223

Measurement of emulsion flow in porous media: Improvements in heavy oil recovery  

NASA Astrophysics Data System (ADS)

Many heavy oil and bitumen reservoirs in the world are too small or thin for thermal enhanced oil recovery methods to be economic. In these fields, novel methods of less energy intensive, non-thermal technologies are required. Previous experience has shown that the injection of low concentrations of aqueous alkali-surfactant solutions into the reservoir can significantly improve the oil recovery, beyond that of waterflooding. This is due to the in-situ formation of emulsions, which plug off the water channels and lead to improved sweep efficiency in the reservoir. The proper control of these floods requires methods for monitoring the formation and effect of these emulsions. In this paper, the results of laboratory core floods are interpreted to demonstrate how the pressure and flow response can be related to the formation of these emulsions. A new technique (low field NMR) is also used to directly measure W/O emulsions in porous media. Finally, a numerical study is performed in order to demonstrate how the in-situ formation of emulsions can be simply represented in simulation software.

Bryan, J.; Wang, J.; Kantzas, A.

2009-02-01

224

The atomization of water-oil emulsions  

SciTech Connect

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)

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

225

Monitoring and Predicting Emulsion Stability of Metalworking Fluids by Salt Titration and Laser Light Scattering Method  

Microsoft Academic Search

The prediction of emulsion stability is very important in the study, formulation, quality control, and technical service of metalworking fluids. Conventional emulsion stability test methods can be very time consuming. One quick method to determine emulsion stability is to titrate an emulsion with a salt solution until the emulsion separates. The salt (or electrolyte) concentration at which an emulsion starts

YIXING PHILIP ZHAO; RUSS TURAY; LLOYD HUNDLEY

2006-01-01

226

Numerical issues in solving population balance equations for particle size distribution control in emulsion polymerization  

Microsoft Academic Search

This work presents numerical studies of solutions to population balance models for latex particle size distributions, using styrene emulsion polymerization as a prototype. Emphasis is placed on control relevant issues such as computational speed and particle size distribution controllability. Simulation results using fixed and moving grid discretizations of the population balance equations are presented. Simulation experiments reveal controllability behavior that

Timothy J. Crowley; Edward S. Meadows; Francis J. Doyle

1999-01-01

227

Observations on the coalescence behavior of oil droplets and emulsion stability in enhanced oil recovery  

Microsoft Academic Search

Results of experiments on the stability of crude oil drops at an oil-water interface and interdroplet coalescence in crude oil-water emulsions containing petroleum sulfonates as surfactant systems, cosurfactants, and other chemical additives have been analyzed in terms of interfacial viscosity, interfacial tension, interfacial charge, and thickness of the films surrounding the microdroplets. A qualitative correlation has been found between coalesence

D. T. Wasan; S. M. Shah; N. Aderangi; M. Chan; J. J. McNamara

1977-01-01

228

Creaming of emulsions: the role of depletion forces induced by surfactant  

Microsoft Academic Search

We show that excess surfactant, or salt, in the bulk phase of an oil in water ionic emulsion has strong consequences on the thermodynamical behavior of the dispersion. Static light scattering experiments have been performed to investigate the attractive interaction induced by micelles according to a depletion mechanism. This interaction can be largely reduced by adding salt. This depletion interaction

J. Bibette; D. Roux; B. Pouligny

1992-01-01

229

Emulsion chamber observations of Centauros, aligned events and the long-flying component  

NASA Astrophysics Data System (ADS)

The cosmic ray emulsion chamber community has reported several unusual phenomena which are also relevant to experiments at the current high-energy accelerators, in particular the Fermilab Tevatron Collider and the CERN Large Hadron Collider (LHC). A summary of the "Cosmic Rays at Mountain Altitude" workshop held at Plock (Poland, September 2010) is given.

Kempa, Janusz; Pattison, Bryan; G?adysz-Dziadu?, Ewa; Jones, Lawrence W.; Mukhamedshin, Rauf; Tamada, Masanobu; W?odarczyk, Zbigniew

2012-08-01

230

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

ERIC Educational Resources Information Center

|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…

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

2008-01-01

231

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

SciTech Connect

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.

Golis, S.W.

1983-02-01

232

High-yield aqueous phase exfoliation of graphene for facile nanocomposite synthesis via emulsion polymerization.  

PubMed

Aqueous phase exfoliation was developed for producing high-yield graphene nanosheets from expanded graphite (EG). The process included ultrasonication with sodium dodecyl sulfate (SDS) emulsion in aqueous phase. The high throughput exfoliation process was characterized by UV-vis spectroscopy, transmission electron microscopy (TEM) and electrical impedance spectroscopy (EIS). Controlled sonication experiments revealed that optimum exfoliation corresponds to maxima in UV-vis spectra. TEM results showed that the exfoliated graphene comprised nanoflakes having ?5 layers (?60%) and ?10 layers for 90% of the product. The potential use of this highly dispersed graphene was demonstrated by one-pot synthesis of graphene/polymer composite via in situ emulsion polymerization with styrene. The integrated role of SDS included adsorption and exfoliation of graphite, dispersion of graphene produced and assisting with micelle formation in emulsion. The high surface area graphene nanosheets as dispersed phase in polymeric nanocomposites showed significant improvement in thermal stability and electrical conductivity. PMID:24034217

Hassan, Mahbub; Reddy, Kakarla Raghava; Haque, Enamul; Minett, Andrew I; Gomes, Vincent G

2013-08-14

233

21 CFR 524.802 - Enrofloxacin, silver sulfadiazine emulsion.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Enrofloxacin, silver sulfadiazine emulsion. 524.802 ...ANIMAL DRUGS § 524.802 Enrofloxacin, silver sulfadiazine emulsion. (a) Specifications...milligrams (mg) enrofloxacin and 10 mg silver sulfadiazine. (b) Sponsor ....

2013-04-01

234

High pressure-resistant nonincendive emulsion explosive  

DOEpatents

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.

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

1994-01-01

235

Particle control of emulsion by membrane emulsification and its applications  

Microsoft Academic Search

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

Tadao Nakashima; Masataka Shimizu; Masato Kukizaki

2000-01-01

236

Testing of microbial demulsifiers with heavy crude emulsions  

Microsoft Academic Search

Summary It has already been demonstrated that model water-in-kerosene systems and toluene diluted heavy crude oil emulsions can be broken by microbial agents. In this studyN. amarae andR. rhodochrous are used on undiluted, water-in-heavy crude oil emulsions. The high viscosity of the undiluted emulsions severely limits the demulsifying ability of the bacteria towards these field emulsions.

M. A. Wilkinson; D. G. Cooper

1985-01-01

237

Thermoset Alkyd-Acrylic Hybrid Emulsions for Coatings  

Microsoft Academic Search

Alkyd acrylic hybrid emulsions can offer cost\\/performance advantages over common 1K coatings such as polyurethane dispersions (PUDs), acrylic emulsions and blends. Hybrid emulsions with different ratios of alkyd resin to acrylic monomers were synthesized. Emulsion with resin-to monomer ratio of 1:1 (wt\\/wt) with total solids as high as 50% had a shelf stability of more than 8 months. Morphology of

Vilas D. Athawale; Ramakant V. Nimbalkar

2011-01-01

238

The primitivity of silver bromoiodide and bromochloride mixed photographic emulsions  

Microsoft Academic Search

The primitivity of silver bromide photographic emulsions to which varying proportions of iodide and chloride have been added is investigated. Blackening curves were obtained for the surface and internal emulsion layers exposed to white light, and primitivity was determined in terms of the restoration of emulsion sensitivity following immersion in chromic acid solutions of varying concentrations by prolonged washing in

Y. Renotte

1979-01-01

239

Stabilization of Oil-Water Emulsions by Hydrophobic Bacteria  

Microsoft Academic Search

Emulsions are commonly observed when liquid hydrocar- bons and water are mixed during bioremediation or fermenta- tion (2). These emulsions dramatically increase the area of the oil-water interface, thereby enhancing bioavailability. For a dispersion of one liquid in another to be stable enough to be classified as an emulsion, a third component, such as a surfac- tant, must be present

Loredana S. Dorobantu; Anthony K. C. Yeung; Julia M. Foght; Murray R. Gray

2004-01-01

240

Automated track recognition and event reconstruction in nuclear emulsion  

Microsoft Academic Search

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

P. Deines-Jones; A. Aranas; M. L. Cherry; J. Dugas; D. Kudzia; B. S. Nilsen; K. Sengupta; C. J. Waddington; J. P. Wefel; B. Wilczynska; H. Wilczynski; B. Wosiek

1997-01-01

241

Heavy-oil-emulsion pipeline tests meet targets  

Microsoft Academic Search

Field trials with the Transoil emulsion technology to produce bitumen-in-water emulsions for pipeline transportation met all objectives set by the Transoil group for parameters of time, flow, and emulsion quality. The Transoil group consists of BP Canada Inc., AEC Pipelines (division of Alberta Energy Co. Ltd.), and BP Canadian Holdings Ltd. Presented here are the details of the field trials

W. A. Hardy; S. P. Sit; A. Stockwell

1989-01-01

242

Stabilization\\/solidification of galvanic sludges by asphalt emulsions  

Microsoft Academic Search

A combination of two-aqueous asphalt emulsions was proposed for stabilization\\/solidification treatment of galvanic sludges prior to landfilling. The presented procedure comprises mixing the galvanic sludge with a slow setting nonionic asphalt emulsion and subsequently forming a secondary asphalt barrier by means of a rapid setting anionic asphalt emulsion. The method was tested on four samples of galvanic sludge from various

Vratislav Bednarik; Milan Vondruska; Marek Koutny

2005-01-01

243

Factors affecting the freeze–thaw stability of emulsions  

Microsoft Academic Search

Many food emulsions are frozen to provide long-term stability to the product or as a necessary part of the food itself (e.g., ice cream), but very often the thawed emulsion is significantly destabilized and sometimes completely broken down into an oily and an aqueous phase. The phase behaviour of the frozen emulsion and hence the potential stresses can be calculated

Supratim Ghosh; John N. Coupland

2008-01-01

244

GAMMA-RAY SENSITIVITY OF SILVER CHLORIDE EMULSIONS  

Microsoft Academic Search

Silver chloride emulsions were prepared in three different ; conipositions, and their gamma-ray sensitivity and light sensitivity were studied. ; It is suggested that the gamma-ray sensitivity of the emulsions depends to some ; extent upon the sensitivity in the higher light exposure region. It was also ; demonstrated that latent image fading of silver chloride emulsions depends on the

Tomoda

1958-01-01

245

Fluorocarbon Emulsion as a Candidate for Artificial Blood  

Microsoft Academic Search

A method of specifying particle size distribution in fluorocarbon emulsion by means of stepwise centrifugation is proposed. On account of very large specific density of fluorocarbon, a physical calculation was made to classify particle size (the maximum and average) of fluorocarbon emulsion in correlation with centrifugal rotation applying Stokes’ law of sedimentation. Samples of FC emulsion were made with different

T. Fujita; T. Sumaya; K. Yokoyama

1971-01-01

246

Combustion of Water/Heavy Fuel Oil Emulsions in Finland.  

National Technical Information Service (NTIS)

The report deals with the use of the water/oil emulsion technique in Finland. About a half of the 500-600 oil fired boilers are equipped with the water/oil emulsion system. Most of the water/oil emulsion installations are in boilers smaller than 5 MW. Pra...

E. Kaukainen A. Pyykkoenen K. Larnimaa

1987-01-01

247

Mathematical modeling of ultrafiltration of emulsions  

SciTech Connect

The goal of this work is development of a mathematical model of the microfiltration process for oil emulsions. First of all to proceed to development of the basic equations describing the process of microfiltration, the authors study several rules obtained as a result of studies carried out in a cold rolling mill on an experimental setup of known construction, which included four F-1 BTU-0.5/2 ultrafilters connected in series, a pump, a 3 m{sup 3} settling tank, and a 1 m{sup 3} tank for the washing solution. An emulsion based on self-emulsifying oil T, which is used for preparing working emulsions for a four-stand cold rolling sheet mill, was purified. 9 refs., 4 figs.

Epshtein, S.I.

1992-07-10

248

Pharmaceutical Nanotechnology The properties of bufadienolides-loaded nano-emulsion and submicro-emulsion during lyophilization  

Microsoft Academic Search

The aim of this study was to prepare two types of emulsions, bufadienolides-loaded nano-emulsion (BU-NE) and submicro-emulsion (BU-SE) which were separately prepared by ultrasonic-high-pressure homogenization (UHPH) and high-pressure homogenization (HPH) methods, and to try to stabilize the colloid systems by lyophilization. The lyoprotective effects of cryoprotectant carbohydrates during the freeze-thawing and freeze-drying cycles on the emulsions were investigated in detail.

Fang Li; Tao Wang; Bing He; Xing Tang

249

Stabilisation of emulsions: influence of hydrophilic colloids.  

PubMed

Synopsis The influence of the following hydrophilic polymers on the stability of emulsions has been studied: sodium carboxymethyl cellulose, hydroxyethyl cellulose, agar-agar, water dispersible clay, and a neutralized polyethylene acid. The oil phases used were paraffin oil, olive oil and a synthetic C(8)-C(12) triglyceride. The other emulsifiers were non ionic-types. After 12 months storage at room temperature, olive oil proved to be the most difficult material to emulsify. The hydrocolloids did not give uniformly better stability to the emulsions and the polyacrylic acid gave the best stability of the colloids tested. PMID:19467110

Saunal, H; Alvarado, D; Et, J P; Delonca, H

1984-08-01

250

STUDIES ON THE NUCLEAR EMULSIONS WITH POLYVINYL ALCOHOL (II). THE GAMMA RAY SENSITIVITY OF THE PVA NUCLEAR EMULSIONS  

Microsoft Academic Search

Silver bromide emulsion was prepared by using polyvinyl alcohol (PVA) as ; the protective colloid, and its photographic properties and deg ray sensitivity ; were studied. The double injector method was used for mixing, and the freezing ; method used for gel formation of the emulsion which contained 70% silver bromide ; by weight. The thickhess of the emulsion layer

Fujii

1961-01-01

251

Linear viscoelasticity of emulsions : II. Measurements of the linear viscoelastic behavior of emulsions in the kilohertz range  

Microsoft Academic Search

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

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

1981-01-01

252

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

PubMed

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

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

2012-08-02

253

Multi-stage shifter for subsecond time resolution of emulsion gamma-ray telescopes  

NASA Astrophysics Data System (ADS)

To observe gamma-ray sources precisely, a balloon-borne experiment with a new type of detector, the emulsion gamma-ray telescope, is planned. A multi-stage shifter mechanism based on the concept of an analog clock serves as a time stamper with subsecond time resolution and uses multiple moving stages mounted on the emulsion chambers. This new technique was employed in a test experiment using a small-scale model in a short-duration balloon flight. Tracks recorded in nuclear emulsion were read by a fully automated scanning system, were reconstructed, and time information were assigned by analysis of their position displacements in the shifter layers. The estimated time resolution was 0.06-0.15 s. The number of tracks passing through the detector was counted every second, and hadron jets were detected as significant excesses observed in the counting rate. In future, the multi-stage shifter is greatly contributing to ongoing efforts to increase the effective area of emulsion gamma-ray telescopes.

Rokujo, H.; Aoki, S.; Takahashi, S.; Kamada, K.; Mizutani, S.; Nakagawa, R.; Ozaki, K.

2013-02-01

254

Ultrasonic energy input influence ?n the production of sub-micron o/w emulsions containing whey protein and common stabilizers.  

PubMed

Ultrasonication may be a cost-effective emulsion formation technique, but its impact on emulsion final structure and droplet size needs to be further investigated. Olive oil emulsions (20wt%) were formulated (pH?7) using whey protein (3wt%), three kinds of hydrocolloids (0.1-0.5wt%) and two different emulsification energy inputs (single- and two-stage, methods A and B, respectively). Formula and energy input effects on emulsion performance are discussed. Emulsions stability was evaluated over a 10-day storage period at 5°C recording the turbidity profiles of the emulsions. Optical micrographs, droplet size and viscosity values were also obtained. A differential scanning calorimetric (DSC) multiple cool-heat cyclic method (40 to -40°C) was performed to examine stability via crystallization phenomena of the dispersed phase. Ultrasonication energy input duplication from 11kJ to 25kJ (method B) resulted in stable emulsions production (reduction of back scattering values, dBS?1% after 10days of storage) at 0.5wt% concentration of any of the stabilizers used. At lower gum amount samples became unstable due to depletion flocculation phenomena, regardless of emulsification energy input used. High energy input during ultrasonic emulsification also resulted in sub-micron oil-droplets emulsions (D(50)=0.615?m compared to D(50)=1.3?m using method A) with narrower particle size distribution and in viscosity reduction. DSC experiments revealed no presence of bulk oil formation, suggesting stability for XG 0.5wt% emulsions prepared by both methods. Reduced enthalpy values found when method B was applied suggesting structural modifications produced by extensive ultrasonication. Change of ultrasonication conditions results in significant changes of oil droplet size and stability of the produced emulsions. PMID:23266492

Kaltsa, O; Michon, C; Yanniotis, S; Mandala, I

2012-11-28

255

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

PubMed

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

Tan, Hui Lin; McGrath, Kathryn M

2012-05-24

256

Lipid Injectable Emulsions: Pharmacopeial and Safety Issues  

Microsoft Academic Search

Abstract  Lipid injectable emulsions have been routinely used in patients worldwide for over 40 years as a nutritional supplement in patients requiring parenteral nutrition. They can be given as a separate infusion or added into total parenteral nutrition admixtures. Despite such broad use, no pharmacopeial standards exist with respect to the optimal pharmaceutical characteristics of the formulation. Several attempts to establish

David F. Driscoll

2006-01-01

257

Characterization of Emulsion Based Warm Mix Binder  

Microsoft Academic Search

The Evotherm warm mix process is the direct substitution of the asphalt binder with a cationic asphalt emulsion. The field trial in Canada demonstrates 30 °C and 60 °C reduction in the mix and compaction temperature, respectively, than the conventional hot mix with the same aggregate and asphalt. This results in 60–80% reduction in CO, NOx and SO2 emission. A

Koichi Takamura

2008-01-01

258

How to avoid emulsions while steaming  

Microsoft Academic Search

A new chemical additive, designed to inhibit downhole oil water emulsions, promises to cut the cost of steam and thermal recovery projects. A considerable volume of steam is required in reservoirs having high viscosity oil. This sometimes results in prohibitive costs. This cost can be cut using a new additive, developed by investigators of Magna Corp. Essentially, the additive is

Rohrback

1966-01-01

259

Autoxidation of Unsaturated Lipids in Food Emulsion  

Microsoft Academic Search

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

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

2011-01-01

260

Semiautomatic scattering measurements in nuclear emulsions  

Microsoft Academic Search

Summary  A simple device is described to semiautomatize scattering measurements and computations, in nuclear emulsion work. Advantages\\u000a of the system achieved in this laboratory are its low cost and a minimum time gain of 4 or more depending on the type of measurements.

C. Castagnoli; M. Ferroo-Luzzi; M. Muchnik

1958-01-01

261

Field Testing of Water Emulsion Epoxies.  

National Technical Information Service (NTIS)

The Civil Engineering Laboratory conducted a field test of two water emulsion epoxy coatings, a low solvent epoxy coating, a regular solvent epoxy coating, and a control alkyd coating. The coatings were placed on either sandblasted steel panels or over we...

R. W. Drisko J. B. Crilly

1975-01-01

262

Alkyd emulsion paints: properties, challenges and solutions  

Microsoft Academic Search

Some of the properties of paints based on alkyd emulsion are discussed and they are divided into four categories. Colloidal stability of water based paints is predominantly governed by osmotic and electrostatic repulsion of both the binder and the pigment particles. The rheological behaviour of paints based on binder dispersions should be optimised by using thickeners with the proper mix

Jochum Beetsma

1998-01-01

263

Thermodynamically stable emulsions using janus dumbbells as colloid surfactants.  

PubMed

One of the most important properties of emulsions is their stability. Most emulsions stabilized with molecular surfactants tend to lose their stability over time via different mechanisms. Although the stability of emulsions stabilized with homogeneous particles have been shown to be superior to that of surfactant-stabilized emulsions, these Pickering emulsions nevertheless are only kinetically stable and thus can undergo destabilization. Janus particles that have two opposite wetting surfaces have shown promise in imparting emulsions with long-term stability because of their strong attachment to the oil-water interface. In this theoretical study, we consider thermodynamics of emulsion stabilization using amphiphilic Janus dumbbells, which are nonspherical particles made of two partially fused spherical particles of opposite wettability. These amphiphilic dumbbells are attractive candidates as colloid surfactants for emulsion stabilization because highly uniform Janus dumbbells can be synthesized in large quantities; thus, their application in emulsion stabilization can become practical. Our theoretical calculation demonstrates that Janus dumbbells can indeed generate thermodynamically stable Pickering emulsions. In addition, we also find that there exists a total oil-water interfacial area that results in the lowest energy state in the system, which occurs when Janus dumbbells available in the system are completely consumed to fully cover the droplet interfaces. We show that the geometry of dumbbells as well as the composition of the emulsion mixtures has significant influences on the average size of dumbbell-stabilized emulsions. We also investigate the effect of asymmetry of Janus dumbbells on the average droplet radius. Our results clearly show that amphiphilic Janus dumbbells provide unique opportunities in stabilizing emulsions for various applications. PMID:24044808

Tu, Fuquan; Park, Bum Jun; Lee, Daeyeon

2013-10-02

264

Automatic readout for nuclear emulsions in muon radiography of volcanoes  

NASA Astrophysics Data System (ADS)

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.

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

265

Entropically Driven Colloidal Assembly in Emulsions  

NASA Astrophysics Data System (ADS)

Using the techniques developed by Manoharan [1], we encapsulate small numbers of colloidal microspheres and polymers in oil-in-water emulsion droplets, remove the oil and generate colloidal clusters covered with polymers. We observe two types of arrangement in the clusters. The first kind is the same as the type reported in [1] of which the clusters are formed without polymer. The second kind is the same as the structure reported in [2] of which the clusters are formed by binary colloidal microspheres. The polymers we put in the emulsions induce depletion interactions between colloidal particles. We will show that two types of structures are from the interplay between the depletion interactions and surface tension. [1] Manoharan, Elsesser, Pine, Science 301, 483(2003). [2] Cho et al. JACS 127, 15968 (2005).

Lin, Keng-Hui; Lai, Liang-Jie; Chen, Hui

2007-03-01

266

Thermoresponsive macroporous scaffolds prepared by emulsion templating.  

PubMed

A versatile method to prepare non-covalently crosslinked polyHIPEs hydrogels from oil-in-water high internal phase emulsions (HIPEs) whose aqueous phase contained thermo-responsive linear polymers is described. The interconnected pore structure of the polyHIPEs is maintained by reversible physical aggregation of thermo-responsive polymer chains in an aqueous environment. This method to prepare interconnected porous hydrogels using a thermal trigger in the guise of thermo-responsive polymers by emulsion templating requires no chemical reaction during solidification of the template. This particular feature could provide a safer route to injectable scaffolds as issues of polymerisation/crosslinking chemistry and residual initiator fragments or monomers do not arise. PMID:22927192

Zhou, Shengzhong; Bismarck, Alexander; Steinke, Joachim H G

2012-08-24

267

Radiobiological aspects of supralinear photographic emulsions.  

PubMed

Nuclear emulsions of the Ilford K series, exposed to X-rays from 15 to 150 kVp and systematically underdeveloped, exhibit supralinear blackness--exposure curves ranging from 1- to 4-hit in character, and whose shape is the same at all excitation voltages. Processing can be so adjusted that the curve shape is well represented by the alpha--beta model, and matches an experimental dose--response curve obtained with hamster cells after irradiation with gamma rays. The effective grain size of these emulsions is 1.3 micron when normalised to unit density material for comparison with the radiation sensitive elements of biological cells. With fractionated exposures, response curves which mimic Elkind recovery are produced. PMID:733900

Katz, R; Pennington, E C

1978-11-01

268

Intravenous Lipid Emulsion for the Treatment of Drug Toxicity.  

PubMed

Intravenous lipid emulsion (ILE) has emerged as a powerful antidote for the treatment of drug toxicity in the past decade. Initial efficacy of ILE was shown in the setting of local anesthetic systemic toxicity (LAST), but recent case reports suggest its consideration in a variety of other drug toxicities. In this review, we will summarize the experimental evidence as well as the clinical experience in using ILE as an antidote. Specifically, we will look at the evidence for using ILE in LAST as well as toxicity due to beta-blockers, calcium-channel blockers, and tricyclic antidepressants. We will also review the current dosing recommendations as well as potential side effects of ILE as an antidote. PMID:22733724

Ozcan, Mehmet S; Weinberg, Guy

2012-06-24

269

Refractive index matching and clear emulsions.  

PubMed

Refractive index (RI) matching is a unique way of making clear emulsions to meet market trends. However, RI matching has not been sufficiently investigated in terms of physical principles and methodologies. Snell's law (n2 sin r2= n1 sin r1) is applicable to cosmetic emulsions. When oil phase and water phase have equal RI (n2 = n1) values, light will not bend as it strikes obliquely at the emulsion interface. Instead, light is transmitted through the emulsion without refraction, which produces clarity. Theoretical RI values in solution can be calculated with summation of the product of the weight percentage and refractive index of each ingredient (RI(mix) = [W1 x n1 + W2 x n2 + W3 x n3 + + Wn x nn]Wtau). Oil-phase RI values are normally at 1.4 or higher. Glycols are used to adjust the water phase RI, since they typically have larger RI values than water. Noticeable deviations from calculated RI values are seen in experimentally prepared solutions. Three basic deviation types are observed: negative, positive, and slightly negative or positive, which can occur in glycol aqueous solutions at different concentrations. The deviations are attributed to changes in molecular interaction between molecules in solution, which can lead to changes in specific gravity. Negative RI deviation corresponds to a decrease in specific gravity, and positive RI deviation corresponds to an increase in specific gravity. RI values will deviate from calculated values since an increase or decrease in specific gravity leads to a change in optical density. PMID:16130046

Sun, James Ziming; Erickson, Michael C E; Parr, James W

270

Emulsion stabilizing properties of depolymerized pectin  

Microsoft Academic Search

Emulsifying properties of depolymerized citrus pectin of 70% esterification and differing molecular weights in the range 48–146kgmol?1 have been investigated in systems containing rapeseed oil (RSO) and D-limonene at pH values 4.7 and 7. Emulsion stability was followed by determining changes in average droplet size and extent of serum separation with time, with gum arabic chosen as the reference emulsifier.

Mahmood Akhtar; Eric Dickinson; Jacques Mazoyer; Virginie Langendorff

2002-01-01

271

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

Code of Federal Regulations, 2011 CFR

...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...

2011-07-01

272

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

Code of Federal Regulations, 2013 CFR

...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...

2013-07-01

273

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

Federal Register 2010, 2011, 2012, 2013

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

2013-09-23

274

Studies of Water-in-Oil Emulsions: Stability Classes and Measurement.  

National Technical Information Service (NTIS)

The paper summarizes studies to determine the stability of water-in-oil emulsions and the measurement of emulsion stability. The most important question related to emulsion analysis is whether they are stable. In the strict thermodynamic sense, all emulsi...

2011-01-01

275

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

Code of Federal Regulations, 2010 CFR

...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...

2009-01-01

276

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

Code of Federal Regulations, 2010 CFR

...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...

2010-07-01

277

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

Code of Federal Regulations, 2010 CFR

...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...

2010-07-01

278

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

Code of Federal Regulations, 2010 CFR

...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...

2009-01-01

279

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

Code of Federal Regulations, 2010 CFR

...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...

2010-07-01

280

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

Code of Federal Regulations, 2010 CFR

...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...

2009-01-01

281

THE INFLUENCE OF HELICAL FLOW ON WATER FUEL EMULSION PREPARATION  

Microsoft Academic Search

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

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

2007-01-01

282

Simple and Multiple Water Fuel Emulsions Preparation in Helical Flow  

Microsoft Academic Search

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

Ewa DLUSKA; Robert HUBACZ; Stanislaw WRONSKI

283

Stability Behavior of Water-in-Diesel Fuel Emulsion  

Microsoft Academic Search

The presence of water within diesel fuel in the form of water-in-diesel (W\\/D) emulsion lowers the pollution level of nitrogen oxides and particulate matter. Emulsion of W\\/D was prepared by high-speed mixing and gradually adding water into the diesel fuel containing a small amount of emulsified agent. We measured the physical properties of diesel fuel and W\\/D emulsions with a

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

2009-01-01

284

Field testing of asphalt-emulsion radon-barrier system  

Microsoft Academic Search

Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10⁻⁶ cm²\\/s. The 1981

J. N. Hartley; H. D. Freeman; E. G. Baker; M. R. Elmore; D. A. Nelson; C. F. Voss; P. L. Koehmstedt

1981-01-01

285

Pipeline flow of unstable and surfactant-stabilized emulsions  

Microsoft Academic Search

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

Rajinder Pal

1993-01-01

286

Method for demulsification of bitumen emulsions using polyalkylene polyamine salts  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/W) emulsions is disclosed wherein water soluble demulsifiers are used. These demulsifiers are polyamine salts prepared by contacting poly(ethyleneimines) with organic or inorganic acids. The polyamines have a molecular weight of at least 1,000. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/ C. wherein the demulsifier of the invention is contacted with the bituminous emulsion.

McCoy, D.R.

1984-03-06

287

Demulsification of bitumen emulsions using water soluble salts of polymers  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/W) emulsions is disclosed wherein water-soluble demulsifiers are used. These demulsifiers are water-soluble salts of polymers prepared by the reaction between certain polyoxyalkylene diamines with diepoxides. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/C. wherein the demulsifier of the invention is contacted with the bituminous emulsion.

McCoy, D.R.; Cuscurida, M.; Speranza, G.P.

1983-08-02

288

Accelerated Stability Testing of a Water-in-Oil Emulsion  

Microsoft Academic Search

Non-optimal or non-predictable stability properties of emulsions can be limiting for the applications of emulsions. Therefore, it is of general interest to predict stability behavior. In the present study, accelerated stability testing employing elevated temperatures with good accuracy predicted long-term stability of a w\\/o emulsion stabilized with polyglycerol polyricinoleate (PG PR) kept at 4°C. It is argued that elevated temperature

S. Bjerregaard; C. Vermehren; I. Söderberg; S. Frokjaer

2001-01-01

289

Automated image analysis as a control tool for multiple emulsions  

Microsoft Academic Search

The industrial preparation of multiple emulsions of the W1\\/O\\/W2 type requires process control of the W1-yield. The aim of this study was to develop automated image analysis of W1\\/O\\/W2 emulsions for visualizing oil droplet size as well as the distribution of the inner aqueous W1-phase. In order to obtain different emulsion properties, i.e. an external oil droplet size 5–50?m, the

Inta Scherze; Ralf Knöfel; Gerald Muschiolik

2005-01-01

290

Polylactide Microparticles Prepared by Double Emulsion-Evaporation  

Microsoft Academic Search

Polylactide and copolymers with glycolide have been used as coating polymers in the microencapsulation technique based on the w1\\/o\\/w2 double emulsion-evaporation method. Stability of the primary emulsion is of critical importance and clearly predetermines the internal morphology of the microspheres, in agreement with the very fast hardening of the oil phase (CH2Cl2) as soon as the primary emulsion is dispersed

Nicole Nihant; Chantal Schugens; Christian Grandfils; Robert Jerome; Philippe Teyssie

1995-01-01

291

Lipid emulsion for local anesthetic systemic toxicity.  

PubMed

The accidental overdose of local anesthetics may prove fatal. The commonly used amide local anesthetics have varying adverse effects on the myocardium, and beyond a certain dose all are capable of causing death. Local anesthetics are the most frequently used drugs amongst anesthetists and although uncommon, local anaesthetic systemic toxicity accounts for a high proportion of mortality, with local anaesthetic-induced cardiac arrest particularly resistant to standard resuscitation methods. Over the last decade, there has been convincing evidence of intravenous lipid emulsions as a rescue in local anesthetic-cardiotoxicity, and anesthetic organisations, over the globe have developed guidelines on the use of this drug. Despite this, awareness amongst practitioners appears to be lacking. All who use local anesthetics in their practice should have an appreciation of patients at high risk of toxicity, early symptoms and signs of toxicity, preventative measures when using local anesthetics, and the initial management of systemic toxicity with intravenous lipid emulsion. In this paper we intend to discuss the pharmacology and pathophysiology of local anesthetics and toxicity, and the rationale for lipid emulsion therapy. PMID:21969824

Ciechanowicz, Sarah; Patil, Vinod

2011-09-29

292

Intravenous lipid emulsion - rescued at LAST.  

PubMed

The accidental overdose of local anaesthetics may prove fatal. The commonly used amide local anaesthetics have varying adverse effects on the myocardium and beyond a certain dose all are capable of causing death. Local anaesthetics are the most frequently used drugs in dentistry and although uncommon, local anaesthetic systemic toxicity (LAST) accounts for a high proportion of mortalities in the dental office, with local anaesthetic-induced cardiac arrest particularly resistant to standard resuscitation methods. Over the last decade there has been convincing evidence of using intravenous lipid emulsions as a rescue in local anaesthetic - cardiotoxicity and anaesthetic organisations over the globe have developed guidelines on the use of this drug. Despite this, however, awareness among practitioners appears to be lacking. All who use local anaesthetics in their practice should have an appreciation of patients at high risk of toxicity, early symptoms and signs of toxicity, preventative measures when using these drugs and the initial management of systemic toxicity with intravenous lipid emulsion. In this review we intend to discuss the pharmacology and pathophysiology of local anaesthetic toxicity, and the rationale for intravenous lipid emulsion therapy. PMID:22402543

Ciechanowicz, S J; Patil, V K

2012-03-09

293

Field testing of asphalt-emulsion radon-barrier system  

SciTech Connect

Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10/sup -6/ cm/sup 2//s. The 1981 joint field test is a culmination of all the technology developed to date for asphalt emulsion radon barrier systems. Preliminary results of this field test and the results of the 1980 field test are presented. 18 figures, 6 tables.

Hartley, J.N.; Freeman, H.D.; Baker, E.G.; Elmore, M.R.; Nelson, D.A.; Voss, C.F.; Koehmstedt, P.L.

1981-09-01

294

Laboratory effectiveness testing of water-in-oil emulsion breakers  

SciTech Connect

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.

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

295

Spherical and Non-Spherical Double Emulsions with Multiple Components  

NASA Astrophysics Data System (ADS)

Monodispersed double emulsions, drops inside of drops, with multiple and tunable components are generated using microfluidics. A fluid dynamic model based on fast camera images of the single step emulsification technique is being developed to determine the critical separation between channels in the injection capillary; this model addresses the maximium number of distinct drops that can be controllably loaded inside a double emulsion for a given diameter capillary. New stable, non-spherical emulsions with two and three different components, Janus and Cerberus emulsions, are also reported.

Adams, Laura; Kodger, Thomas; Bird, Jacy; Kim, Shin-Hyun; Jawerth, Louise; Manoharan, Vinothan; Weitz, David

2012-02-01

296

Studies with a safflower oil emulsion in total parenteral nutrition.  

PubMed Central

The prevention of essential fatty acid deficiency and the provision of adequate amounts of energy are two major concerns in total parenteral nutrition. Since earlier preparations of fat emulsion used to supplement the usual regimen of hypertonic glucose and amino acids have widely varying clinical acceptability, a new product, a safflower oil emulsion available in two concentrations (Liposyn), was evaluated. In four clinical trials the emulsion was used as a supplement to total parenteral nutrition. In five surgical patients 500 ml of the 10% emulsion infused every third day prevented or corrected essential fatty acid deficiency; however, in some cases in infusion every other day may be necessary. In 40 patients in severe catabolic states the emulsion provided 30% to 50% of the energy required daily: 10 patients received the 10% emulsion for 14 to 42 days, 9 patients received each emulsion in turn for 7 days, and 21 patient received the 20% emulsion for 14 to 28 days. All the patients survived and tolerated the lipid well; no adverse clinical effects were attributable to the lipid infusions. Transient mild, apparently clinically insignificant abnormalities in the results of one or more liver function tests and eosinophilia were observed in some patients. Thus, the safflower oil emulsion, at both concentrations, was safe and effective as a source of 30% to 50% of the energy required daily by seriously ill patients.

Wong, K. H.; Deitel, M.

1981-01-01

297

Effect of primary emulsions on microsphere size and protein-loading in the double emulsion process.  

PubMed

Incorporation of a protein drug in microspheres made of a hydrophobic polymer is commonly achieved via double liquid-liquid emulsification (w/o/w) or by dispersing a powdered protein in a polymer solution followed by liquid-liquid emulsification (s/o/w). This study focused on the effect of the first operating step in both processes on the size and protein-loading of the microspheres. Bovine serum albumin (BSA) was used as the model protein and poly(methyl methacrylate) (PMMA) was used as the model polymer. The w/o emulsion was characterized based on the degree of emulsion fineness which was controlled using rotor/stator homogenization. The s/o emulsion was characterized based on protein powder size and shape. Protein powders of different sizes and shapes were produced using different powder preparation methods. In both emulsification processes, the second operating step which produced the microspheres was conducted in either a continuously stirred tank reactor (CSTR) or a static mixer. The size of the microspheres thus prepared was found to increase with increasing size of the protein powder in the s/o/w system but increase with decreasing size of the liquid emulsion droplets in the w/o/w system. Empirical correlations can accurately predict the size of the microspheres if the size of w/o emulsion droplets and protein powder is 10 x less than the microsphere size. Protein loading in the microspheres decreased with respect to increases in w/o emulsion droplet size or in protein powder size. We propose that these phenomena are attributed to two mechanisms, fragmentation along the weak routes in the w/o/w system and particle redistribution as the result of terminal velocity in the s/o/w system. The role of protein powder shape was not significant until the protein powder size exceeded 5 microns. Irregular-shaped protein powders resulted in lower encapsulation efficiency than spherical-shaped protein powders. PMID:9132473

Maa, Y F; Hsu, C C

298

Combined effect of hydrophobation and durability improvement of wood treated with silicone emulsions  

Microsoft Academic Search

Silicone emulsions with three different functional groups and sizes of emulsion particles, i.e., quat-silicone micro-emulsion (<40 nm), amino-silicone macro-emulsion (110 nm) and silicone macro-emulsion with alkyd modified side group (740 nm) were impregnated into Scots pine (Pinus sylvestris L.) sapwood and beech wood (Fagus sylvatica L.) to impart hydrophobicity and improve durability. All the emulsions made wood hydrophobic which was

Holger Militz; Carsten Mai; Shyamal C Ghosh

299

Nuclear interactions of super high energy cosmic-rays observed in mountain emulsion chambers  

Microsoft Academic Search

Here we present a summary of joint discussions on the results of three mountain experiments with large-scale emulsion chambers, at Pamir, Mt. Fuji and Chacaltaya. Observations cover gamma quanta, hadrons and their clusters (called ``families''). The following topics are covered, concerning the characteristics of nuclear interactions the energy region 1014-1016 eV: (i) rapid dissipation seen in atmospheric diffusion of high-energy

S. G. Bayburina; A. S. Borisov; K. V. Cherdyntseva; Z. M. Guseva; V. G. Denisova; A. M. Dunaevskii; E. A. Kanevskaya; V. M. Maximenko; S. V. Pashkov; V. S. Puchkov; S. B. Shaulov; S. A. Slavatinsky; M. D. Smirnova; Yu. A. Smorodin; A. V. Urysson; N. G. Zelevinskaya; G. B. Zhdanov; L. G. Afanasjeva; L. T. Baradzei; E. I. Gorochova; I. P. Ivanenko; N. P. Iljina; G. B. Khristiansen; T. V. Lazareva; A. K. Managadze; E. A. Murzina; I. V. Rakobolskaya; T. M. Roganova; N. G. Ryabova; G. T. Zatsepin; R. A. Mukhamedshin; S. D. Cananov; L. A. Khisanishvili; N. N. Roinishvili; M. S. Svanidge; J. A. Tecliashvili; T. V. Varsimashvili; Z. A. Azimov; I. B. Bodojanov; N. E. Gubar; Yu. A. Gulov; F. Normuradov; Kh. Shobaronov; N. A. Dobrotin; Yu. A. Emeljanov; Yu. T. Lukin; B. F. Shorin; E. G. Zaitseva; S. A. Azimov; A. R. Dzhuraev; E. G. Mulladjanov; Kh. Nutritdinov; D. A. Talipov; I. Shamansurov; T. S. Juldashbaev; Z. Buja; E. Gladysz; J. Mazurkiewicz; S. Mikocki; M. Szarska; L. Zawiejski; H. Bielawska; R. Juskiewicz; J. L. Kacperski; A. Krys; J. Malinowski; K. Milczarek; J. Sroka; A. Tomaszewski; J. A. Wrotniak; K. Maluszynska; Z. Wlodarczyk; M. Akashi; M. Amenomori; E. Konishi; H. Nanjo; Z. Watanabe; K. Mizutani; K. Kasahara; S. Torii; T. Yuda; T. Shirai; N. Tateyama; T. Taira; I. Mito; M. Shibata; H. Sugimoto; K. Taira; N. Hotta; M. Ballester; C. Santos; J. Bellandi Filho; J. A. Chinellato; C. Dobrigkeit; C. M. G. Lattes; A. Marques; M. J. Menon; C. E. Navia O; K. Sawayanagi; E. Silva; E. H. Shibuya; A. Turtelli; N. M. Amato; F. M. Oliveira Castro; R. H. C. Maldonado; H. Aoki; Y. Fuyimoto; S. Hasegawa; H. Kumano; H. Semba; T. Tabuki; M. Tamada; K. Tanaka; S. Yamashita; N. Arata; T. Shibata; K. Yokoi; A. Ohsawa

1981-01-01

300

Interactions of 10.6 GeV\\/nucleon gold nuclei in nuclear emulsion  

Microsoft Academic Search

Stacks of nuclear emulsion were exposed at the Brookhaven AGS to a 10.6 GeV\\/n beam of gold nuclei in the BNL 868 experiment. A preliminary analysis of the main features of the interactions of these nuclei is reported here and compared with those observed previously at lower energies,E<1 GeV\\/n. The multiplicity and pseudo-rapidity distributions of the singly charged particles emitted

M. L. Cherry; A. Dabrowska; P. Deines-Jones; A. J. Dubinina; R. Holynski; W. V. Jones; A. Jurak; E. D. Kolganova; A. Olszewski; E. A. Pozharova; K. Sengupta; T. Yu. Skorodko; V. A. Smirnitski; M. Szarska; C. J. Waddington; J. P. Wefel; B. Wilczynska; W. Wolter

1994-01-01

301

Measurement of beauty hadron pair production in 600 GeV\\/c pi- emulsion interactions  

Microsoft Academic Search

We report on the production characteristics and total cross section for 9 beauty hadron pairs produced by a 600 GeV\\/c pi- beam, the first such information in this energy region. The events were detected in the hybrid emulsion spectrometer of Fermilab Experiment E653. The measured pair cross section for all chiF, assuming linear A dependence, is 33+\\/-11 (stat.)+\\/-6(syst.) nb\\/nucleon. Fits

K. Kodama; N. Ushida; A. Mokhtarani; V. S. Paolone; J. T. Volk; J. O. Wilcox; P. M. Yager; R. M. Edelstein; A. P. Freyberger; D. B. Gibaut; R. J. Lipton; W. R. Nichols; D. M. Potter; J. S. Russ; C. Zhang; Y. Zhang; H. I. Jang; J. Y. Kim; T. I. Kim; I. T. Lim; M. Y. Pac; B. R. Baller; R. J. Stefanski; K. Nakazawa; K. S. Chung; S. H. Chung; D. C. Kim; I. G. Park; M. S. Park; J. S. Song; C. S. Yoon; M. Chikawa; T. Abe; T. Fujii; K. Fujiwara; H. Fukushima; T. Hara; Y. Takahashi; K. Taruma; Y. Tsuzuki; C. Yokoyama; S. D. Chang; B. G. Cheon; J. H. Cho; J. S. Kang; C. O. Kim; K. Y. Kim; T. Y. Kim; J. C. Lee; S. B. Lee; G. Y. Lim; S. W. Nam; T. S. Shin; K. S. Sim; J. K. Woo; Y. Isokane; Y. Tsuneoka; S. Aoki; A. Gauthier; K. Hoshino; H. Kitamura; M. Kobayashi; M. Miyanashi; K. Nakamura; Y. Nakamura; S. Nakanishi; K. Niu; K. Niwa; M. Nomura; H. Tajima; S. Yoshida; M. Aryal; J. M. Dunlea; S. G. Frederiksen; S. Kuramata; B. G. Lundberg; G. A. Olevnik; N. W. Reay; K. Reibel; R. A. Sidwell; N. R. Stanton; K. Moriyama; H. Shibata; G. R. Kalbfleisch; P. Skubic; J. M. Snow; S. E. Willis; O. Kusumoto; T. Okusawa; M. Teranaka; T. Tominaga; T. Yoshida; H. Yuuki; H. Okabe; J. Yokota; M. Adachi; M. Kazuno; E. Niu; H. Shibuya; S. Watanabe; I. Ohtsuka; Y. Sato; I. Tezuka; S. Y. Bahk; S. K. Kim

1993-01-01

302

The SPHINX code for simulation of processes in X-ray emulsion chambers  

NASA Astrophysics Data System (ADS)

A three-dimensional Monte Carlo program is elaborated for simulations of processes in X-ray emulsion chambers and measurement procedures used in experiments both aboard stratospheric balloons and at mountain altitudes. The code is applicable from ˜ 1 GeV to extremely high energies (˜ 10 PeV) for arbitrary type of chamber design including lead, carbon, rubber, air, e.g. The code is easy in use and of access for all the persons via Internet.

Mukhamedshin, R. A.

303

Determination of permeability characteristics from centrifugal flotation velocity of deformable oil droplets in O\\/W emulsions  

Microsoft Academic Search

The permeability characteristics of highly concentrated O\\/W emulsions were clarified on the basis of the kinetic data of the centrifugal flotation experiments with the aid of an analytical centrifuge which could monitor timed near-infrared (NIR) transmission profiles of the samples in the centrifugal field, and then the permeability data of the soft particles of oil droplets were compared with those

Eiji Iritani; Nobuyuki Katagiri; Kozue Aoki; Miho Shimamoto; Kyong-Min Yoo

2007-01-01

304

Primary cosmic ray mass composition seen through gamma rays detected by passive balloon-borne emulsion chambers  

Microsoft Academic Search

The gamma rays detected by passive balloon-borne emulsion chambers in the stratosphere allow indirect testing of the conclusions based on the analysis of the primary particle tracks. Here we show that observed experimental data on gamma rays are in agreement with the atmospheric origin of their production. It can be seen that gamma rays from different passive balloon-borne experiments are

V. KOPENKIN

305

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

SciTech Connect

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.

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

1981-11-01

306

The Facility for Antiproton and Ion Research and the Compressed Baryonic Matter Experiment  

NASA Astrophysics Data System (ADS)

The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific activities at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at high densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure both bulk observables with large acceptance and rare diagnostic probes such as charmed particles and vector mesons decaying into lepton pairs. The layout and the physics performance of the proposed CBM experimental facility will be discussed.

Senger, P.

2010-08-01

307

The Facility for Antiproton and Ion Research and the Compressed Baryonic Matter Experiment  

SciTech Connect

The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific activities at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at high densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure both bulk observables with large acceptance and rare diagnostic probes such as charmed particles and vector mesons decaying into lepton pairs. The layout and the physics performance of the proposed CBM experimental facility will be discussed.

Senger, P. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

2010-08-04

308

Study of heavy-ion collisions in the PHENIX experiment: Survey of the most recent results  

SciTech Connect

The first experimental results obtained at the Relativistic Heavy Ion Collider (RHIC) over the period between 2000 and 2005 are indicative of the production of dense and hot partonic matter in relativistic heavy-ion collisions. Investigations performed in recent years make it possible to extend the list of measured signatures and to study their dependence on the greater number of variables. The most recent results obtained in the PHENIX experiment by studying proton-proton and nucleus-nucleus collisions are surveyed. Particular attention is given to studying the properties of the initial state, dynamical evolution of the product medium, and its response to the propagation of high-energy partons through it. The aforementioned effects are studied via measuring the properties of identified hadrons and leptons over a broad region of transverse momenta at various rapidities.

Riabov, V. G., E-mail: riabovvg@mail.pnpi.spb.ru; Samsonov, V. M., E-mail: samsonov@mail.pnpi.spb.ru [Russian Academy of Sciences, Petersburg Nuclear Physics Institute (Russian Federation)

2011-03-15

309

Crude oil emulsions containing a compatible fluorochemical surfactant  

SciTech Connect

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.

Karydas, A.; Rodgers, J.

1991-02-19

310

Method of oil well corrosion inhibition via emulsions and emulsions therefore  

Microsoft Academic Search

This patent describes a method of inhibiting corrosion in an oil well. It comprises introducing to the annulus of a well an effective amount of a pourable emulsion comprising 50 to 95 volume percent of a continuous oil phase, the oil phase containing a corrosion inhibiting amount of an oil soluble corrosion inhibiting compound.

E. C. French; W. F. Fahey; J. G. Harte

1991-01-01

311

Characteristics of Electrorheological Responses in an Emulsion System  

PubMed

The characteristics of electrorheological (ER) responses in an emulsion system have been examined for the first time. The emulsion system consists of a chlorinated paraffin oil and a silicone oil; these two liquids have similar dielectric constants, but the former liquid is 1000 times more conductive than the latter liquid. The mismatch in electric properties between the dispersed phase and the dispersing medium can be reversed in an emulsion by inverting the phase distribution. Transient ER responses in the emulsion system have been studied over a range of shear rates following step changes (on/off) of an external dc electric field. The relative response strength characterizing the ER effect increases with the field strength and with the volume fraction of silicone oil, but decreases with increasing shear rate imposed. The paraffin oil-in-silicone oil emulsion exhibits a response much stronger than that observed in the phase-reversed silicone oil-in-paraffin oil emulsion. No negative ER response is detected in the silicone oil-in-paraffin oil emulsion. With an optical microscope, very different microscopic response characteristics are observed for the phase-reversed emulsions under static conditions, and this can be explained according to the leaky dielectric liquid model of Taylor. Copyright 1997 Academic Press. Copyright 1997Academic Press PMID:9441611

Pan; McKinley

1997-11-01

312

Influence of interfacial properties on perfluorocarbon\\/aqueous emulsion stability  

Microsoft Academic Search

Perfluorocarbon liquid emulsion systems were prepared containing lecithin, mixtures of synthetic phospholipids, cholesterol, cholesterol oleate and Pluronic F68 as emulsifiers. Attempts were made to correlate the stability of the various emulsion systems with their interfacial tension and charge properties. Due to batch to batch variability in the composition of natural egg yolk lecithin, a standard phospholipid mixture was formulated to

Diane J. Burgess; Joseph K. Yoon

1995-01-01

313

Particle settling in oil-in-water emulsions  

Microsoft Academic Search

The sedimentation velocity of precision steel spheres in several oil-in-water emulsions stabilized by a range of commercially available surfactants has been measured. In particular, the interaction between the size distribution of oil droplets, the viscosity of emulsions and the terminal velocity of spheres has been investigated in the Reynolds number range ?10 to ?1000. When the oil droplets are much

D. Beydoun; D. Guang; R. P. Chhabra; J. A. Raper

1998-01-01

314

FLOW PROPERTIES OF WEATHERED CRUDE OILS AND THEIR EMULSIONS  

Microsoft Academic Search

The present paper proposes the emulsification of weathered crude oils in water as a competitive and cost effective method for reducing their viscosities. Weathered crude oil samples were collected from major Kuwaiti oil lakes. Emulsion preparation involved using, either a nonionic surfactant or alkali, as well as both alkali and fatty acid. The obtained emulsions were characterized by measuring the

Ahmed A. Elgibaly; Ibrahim S. Nashawi; Mahmoud A. Tantawy; Ali Elkamel

1999-01-01

315

Stability and demulsification of emulsions stabilized by asphaltenes or resins  

Microsoft Academic Search

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

Lixin Xia; Shiwei Lu; Guoying Cao

2004-01-01

316

Superhydrophobic cellulose-based bionanocomposite films from Pickering emulsions  

Microsoft Academic Search

Inherently superhydrophobic and flexible cellulose-based bionanocomposites were fabricated from solid stabilized (Pickering) emulsions. Emulsions were formed by dispersing cyclosiloxanes in water stabilized by layered silicate particles and were subsequently modified by blending into a zinc oxide nanofluid. The polymer matrix was a blend of cellulose nitrate and fluoroacrylic polymer (Zonyl 8740) precompatibilized in solution. Coatings were spray cast onto aluminum

Ilker S. Bayer; Adam Steele; Philip J. Martorana; Eric Loth; Lance Miller

2009-01-01

317

PREPARATION OF ANIONIC ASPHALT EMULSION BY PARTIAL SULPHONATION  

Microsoft Academic Search

Sulphonates that work as emulsifiers in asphalt emulsification are generated in-situ by partial sulphonation of asphalt. More stable emulsions can be made by using sulphonated asphalt with a conventional emulsifier. To demonstrate, the sodium oleate was used as co-emulsifier. Effect of sulphonation time, temperature, acid concentration and amount of sulphonated asphalt on emulsion properties is studied. Use of 2 factorial

Sleem-ur-Rahman; M. C. Dwivedi

1997-01-01

318

Feasibility study of asphalt-modified mortars using asphalt emulsion  

Microsoft Academic Search

Asphalt emulsion is manufactured by emulsification of asphalt, and it is an energy-saving, ecologically safe material because it does not need any heating processes creating gas emission and fire hazard in its use. The purpose of this study is to evaluate the feasibility on the use of an asphalt emulsion as a polymeric admixture. Asphalt-modified mortars using an experimentally manufactured

Hun Song; Yangseob Soh

2006-01-01

319

Synthesis of metallic nanoshells on porphyrin-stabilized emulsions  

DOEpatents

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.

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

2011-12-13

320

Preparation of food emulsions using a membrane emulsification system  

Microsoft Academic Search

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

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

1996-01-01

321

DEMULSIFICATION OF WATER IN OIL EMULSIONS USING WATER SOLUBLE DEMULSIFIERS  

Microsoft Academic Search

The possibility of using a water soluble,as opposed to the conventional oil soluble demulsifier, to destabilize a w\\/o emulsion in crude oil has been explored. It was found experimentally that a surfactant soluble in the water (dispersed) phase could destabilize the emulsion. Polymer molecules with varying HLB's and molecular weights and structure were synthesized and these compounds were added to

C. S. Shetty; A. D. Nikolov; D. T. Wasan; B. R. Bhattacharyya

1992-01-01

322

Preparation of double emulsions by membrane emulsification—a review  

Microsoft Academic Search

Double emulsions have potential for the production of low calorie food products, encapsulation of medicines and other high value products. The main issue is the difficulty to efficiently produce double emulsions in a well controlled manner due to their shear sensitivity. In membrane emulsification only mild shear stresses are applied and it is therefore expected that this process is very

S. van der Graaf; C. G. P. H. Schroën; R. M. Boom

2005-01-01

323

Demulsification of Emulsions Exploited by Enhanced Oil Recovery System  

Microsoft Academic Search

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

Lixin Xia; Shiwei Lu; Guoying Cao

2003-01-01

324

Influence of emulsifier on the formation of alkyd emulsions  

Microsoft Academic Search

In traditional alkyd paints, the alkyd is dissolved in an organic solvent such as mineral spirit. For health and environmental reasons there is an increasing interest in water-borne alkyd paints. Alkyd emulsions are therefore an interesting alternative. The alkyd emulsion should have a good colloidal stability at a low concentration of surfactant. A high concentration of surfactant gives undesired properties

M. Hulde´n

1995-01-01

325

An Evaluation of Emulsion Type Traffic Marking Paints.  

National Technical Information Service (NTIS)

The emulsion or waterbase type paints were field tested in 1964 and 1967 to evaluate their performance as pavement markings. Also investigated were the effects on durability of pre-heating the emulsions. As a result of these field tests it was found that ...

D. R. Brewster J. T. Capelli

1969-01-01

326

Static and Dynamic Light Scattering of Dilute Magnetorheolgical Emulsions  

Microsoft Academic Search

The structure formation and dynamics of a dilute, monodisperse ferrofluid emulsion under the influence of an external magnetic field have been investigated using static and dynamic light scattering techniques. In the absence of an external field, the spherical emulsion particles behave as a dilute system of hard spheres where the static light scattering is dominated by the droplet form factor

M. Hagenbüchle; P. Sheaffer; Y. Zhu; J. Liu

1996-01-01

327

Perfluorochemical emulsions decrease Kupffer cell phagocytosis  

SciTech Connect

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. The authors 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. They 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.

Bottalico, L.A.; Betensky, H.T.; Min, Y.B.; Weinstock, S.B. (Department of Chemistry, Barnard College, Columbia University, New York (USA))

1991-07-01

328

The properties of bufadienolides-loaded nano-emulsion and submicro-emulsion during lyophilization.  

PubMed

The aim of this study was to prepare two types of emulsions, bufadienolides-loaded nano-emulsion (BU-NE) and submicro-emulsion (BU-SE) which were separately prepared by ultrasonic-high-pressure homogenization (UHPH) and high-pressure homogenization (HPH) methods, and to try to stabilize the colloid systems by lyophilization. The lyoprotective effects of cryoprotectant carbohydrates during the freeze-thawing and freeze-drying cycles on the emulsions were investigated in detail. The lyophilized products were characterized with regard to their appearance and particle size by transmission electron microscopy (TEM), scanning electron microscopy (SEM), photon correlation spectroscopy (PCS) and zeta potential. The median diameter, polydispersity index (PI) and zeta potential of BU-NE and BU-SE were 43.5 nm versus 161.4 nm, 0.100 versus 0.143 and -19.7 to -26.2 mV versus -29.4 to -35.3 mV, respectively. With the same drug content (0.28 mg mL(-1)) BU-SE exhibited a higher entrapment efficiency than BU-NE. The optimum cryoprotectant for BU-NE and BU-SE was maltose (20%) and trehalose (20%), respectively. The median diameters (95.7 and 168.5 nm) of the rehydrated BU-NE and BU-SE were slightly increased. For both of them, the bufadienolides entrapment efficiency was reduced whereas the drug content was not. The lyophilized BU-NE and BU-SE powders were stable over a period up to 3 months with no change in visual appearance, reconstitution ability, particle size distribution and drug concentration. This shows that freeze-drying could be a promising method to stabilize the emulsions. PMID:17889466

Li, Fang; Wang, Tao; He, Hai Bing; Tang, Xing

2007-08-19

329

Mechanistic study on demulsification of water-in-diluted bitumen emulsions by ethylcellulose.  

PubMed

In our previous study, ethylcellulose (EC), an effective, nontoxic, and biodegradable natural polymer, was found effective in dewatering water-in-diluted bitumen emulsions. In this study, the demulsification mechanism of water-in-diluted bitumen emulsions by EC is investigated. In situ experiments using a micropipet apparatus provided direct evidence on both flocculation and coalescence of water droplets in diluted bitumen by EC. The addition of EC was found to decrease naphtha-diluted bitumen-water interfacial tension significantly. At the molecular level, AFM imaging revealed disruption of the continuous interfacial films formed from surface-active components of bitumen by EC. Our study clearly indicates that the demulsification by EC is through both flocculation and coalescence of water droplets, attained by competitive adsorption of EC at the oil-water interface and disruption of the original protective interfacial films formed from the surface-active components of bitumen. PMID:20175568

Feng, Xianhua; Mussone, Paolo; Gao, Song; Wang, Shengqun; Wu, Shiau-Yin; Masliyah, Jacob H; Xu, Zhenghe

2010-03-01

330

Development of an Acoustic Droplet Vaporization, Ultrasound Drug Delivery Emulsion  

NASA Astrophysics Data System (ADS)

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.

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

2010-03-01

331

Particle control of emulsion by membrane emulsification and its applications.  

PubMed

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 'membrane emulsification'. Applications of membrane emulsification technology to drug delivery systems were carried out under cooperative research with Miyazaki Medical College. It was found that the clinical administration of a W/O/W drug emulsion that encapsulated an anticancer drug in its inner droplets was surprisingly effective for both terminal and multiple nodules of hepatocellular carcinoma when the drug was injected to damaged liver through a catheter inserted in the hepatic artery. Other applications have been tried and developed elsewhere. PMID:11104896

Nakashima, T; Shimizu, M; Kukizaki, M

2000-12-01

332

Heavy Particles in Primary Cosmic Radiation.  

National Technical Information Service (NTIS)

The research program has included studies of the composition and the energy spectrum of the primary cosmic radiation and studies of nucleus-nucleus interactions at medium and high energies. The investigations have been performed with nuclear emulsions whi...

S. von Friesen

1969-01-01

333

Emulsion droplet formation in coflowing liquid streams.  

PubMed

We investigate emulsion droplet formation in coflowing liquid streams based on a computational fluid dynamics simulation using the volume-of-fluid method to track the interface motion with a focus on the dynamics of the dripping and jetting regimes. The simulations reproduce dripping, widening jetting and narrowing jetting simultaneously in a coflowing microchannel in agreement with the experimental observations in this work. The result indicates that the dripping regime, rather than the jetting regime, is a favorable way to producing monodisperse emulsions. We find that, in dripping and widening jetting regimes, the breakup of a drop is induced by higher pressure in the neck which squeezes liquid into the lower-pressure region in subsequent and primary droplets, while the breakup in the narrowing jetting regime is due to slow velocity at the back end of the trough with respect to the leading end of the trough. In addition, the capillary number of the outer fluid and the Weber number of the inner fluid not only determine the drop diameter and generation rate but also the regime of emulsification. PMID:23410421

Chen, Yongping; Wu, Liangyu; Zhang, Chengbin

2013-01-03

334

Crude Oil Emulsion Properties and Their Application to Heavy Oil Transportation  

Microsoft Academic Search

Crude Oil Emulsion Properties and their Application to Heavy Oil Transportation — Many advances have been made in the field of emulsions in recent years. Emulsion behavior is largely controlled by the properties of the adsorbed layers that stabilize the oil-water surfaces. The knowledge of surface tension alone is not sufficient to understand emulsion properties, and surface rheology plays an

D. Langevin; S. Poteau; I. Hénaut; J. F. Argillier

2004-01-01

335

Removal kinetic model of oil droplet from o/w emulsion by adding methylated milk casein in flotation.  

PubMed

In this study, o/w emulsion flotation experiments were conducted by adding methylated milk casein (MeSC). Emulsion used in this study was prepared by ultrasonic emulsification of heavy oil (bunker-A) and sodium dodecyl sulfate (SDS) solution. A simple kinetic model was proposed to estimate the removal rate of the oil droplets within the column. The model was based on main assumption that adsorption of single droplet adsorbed MeCS or floc onto bubble surface within flotation column. Removal rate constant, K, was defined by k(a)X(s) (S(b)?/V), where k(a) and X(s) are overall adsorption rate and saturated adsorption density of oil droplet or floc, S(b), ? and V are bubble surface production rate, retention time of bubble swarms and emulsion volume within the column, respectively. The experiments were conducted with varying operating conditions; superficial gas velocity, column dimension and emulsion volume. K was evaluated from slope value of obtained straight line by plotting time versus ln (T/T(0)), where T/T(0) is relative turbidity. K was mostly proportional to (S(b)?/V), which corresponds to specific surface area of bubble swarms per unit volume within the column, in the present experimental region. This result suggested that efficiency of this removal process was mainly controlled by the specific surface area of bubble swarms, and proposed model was fundamentally verified. PMID:22483713

Maruyama, Hideo; Seki, Hideshi; Satoh, Yuuki

2012-03-21

336

Factors that affect Pickering emulsions stabilized by graphene oxide.  

PubMed

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

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

2013-05-16

337

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

NASA Astrophysics Data System (ADS)

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.

Rozairo, Damith P.; Croll, Andrew B.

2013-03-01

338

Small-angle neutron scattering study of temperature-induced emulsion gelation: the role of sticky microgel particles.  

PubMed

In this work, small-angle neutron scattering (SANS) is used to probe the structural transformations that accompany temperature-induced gelation of emulsions stabilized by a temperature-responsive polymer. The latter is poly(NIPAM-co-PEGMa) (N-isopropylacrylamide and poly(ethyleneglycol) methacrylate) and contains 86 mol% NIPAM. Turbidity measurements revealed that poly(NIPAM-co-PEGMa) has a lower critical solution temperature (T(LCST)) of 36.5 degrees C in D(2)O. Aqueous polymer solutions were used to prepare perfluorodecalin-in-water emulsions (average droplet size of 6.9 mum). These emulsions formed gels at 50 degrees C. SANS measurements were performed on the poly(NIPAM-co-PEGMa) solutions and emulsions as a function of temperature. The emulsion was also prepared using a D2O/H2O mixture containing 72 vol% D2O in order to make scattering from the droplets negligible (on-contrast). The SANS data were analyzed using a combination of Porod and Ornstein-Zernike form factors. The results showed that the correlation length (xi) of the polymer scaled as xi approximately phi(p)(-0.68) at 32 degrees C, where phi(p) is the polymer volume fraction. The xi value increased for all systems as the temperature increased, which was attributed to a spinodal transition. At temperatures greater than T(LCST), the polymer solution changed to a polymer dispersion of poly(NIPAM-co-PEGMa) aggregates. The aggregates have features that are similar to microgel particles. The average size of these particles was estimated as 160-170 nm. The particles are "sticky" and are gel-forming. The on-contrast experiments performed using the emulsion indicated that the interfacial polymer chains condensed to give a relatively thick polymer layer at the perfluorodecalin-water interface at 50 degrees C. The gelled emulsions appear to consist of perfluorodecalin droplets with an encapsulating layer of collapsed polymer to which sticky microgel particles are adsorbed. The latter act as a "glue" between coated droplets in the emulsion gel. PMID:16008382

Koh, Andrew Y C; Saunders, Brian R

2005-07-19

339

Progress in Stabilization and Transport Phenomena of Double Emulsions in Food Applications  

Microsoft Academic Search

Multiple emulsions are complex systems of emulsion within an emulsion, where the droplets of the dispersed phase themselves contain even smaller dispersed droplets. The two major types are water-in-oil-in-water (W\\/O\\/W) and oil-in-water-in-oil (O\\/W\\/O) double emulsions.Double emulsions are unstable thermodynamic systems, which tend to cream, flocculate and coalesce. Much effort has been made to develop methods of ‘better sealing’ in the

Nissim Garti

1997-01-01

340

A theoretical model for transdermal drug delivery from emulsions and its dependence upon formulation.  

PubMed

This article presents a theoretical model of transdermal drug delivery from an emulsion-type vehicle that addresses the vehicle heterogeneity and incorporates the prediction of drug transport parameters as function of the vehicle composition. The basic mass transfer model considers interfacial and diffusion resistances within the emulsion and partition/diffusion phenomena across two skin compartments in series. Drug transport parameters are predicted as follows: partition coefficients are derived from regular solutions theory, drug diffusivity in the continuous phase is computed from a free volume theory with segmental motion, and permeability of the surfactant layer around droplets is estimated based on a free surface area model. These relationships are incorporated within the basic mass transfer model, so that the overall model is able to predict temporal profiles of drug release from the vehicle and of drug concentration in plasma, as a function of vehicle composition. In this way, the proposed model provides a sound physicochemical basis to support the development of new formulations and the planning of experiments. A simulated case study regarding a nitroglycerin ointment is presented in detail, illustrating how thermodynamic and kinetic factors inherent to the emulsion vehicle can modulate drug release and subsequent systemic absorption. PMID:18186500

Bernardo, Fernando P; Saraiva, Pedro M

2008-09-01

341

Highly unsaturated fatty acid might act as an antioxidant in emulsion system oxidized by azo compound.  

PubMed

Now it is recognized that DHA is oxidatively stable fatty acid compared with linoleic acid (LA) in emulsified system, although DHA is oxidatively unstable in a bulk system. In fact, an emulsified mixture of DHA and LA behaves as in a bulk system, namely the oxidative stability of DHA becomes lower than that of LA. Therefore, in this study, tridocosahexaenoate (DDD) and glycerol trilinoleate (LLL) were separately emulsified using TritonX-100 as an emulsifier and DDD emulsion was mixed with the oxidizing LLL emulsion using a water-soluble radical initiator, 2,2'-azobis(2-aminopropane) dihydrochloride. As a result, DHA suppressed the oxidation of LA, while DHA was not significantly oxidized. This suppression ability was examined using glycerol trieicosapentaenoate, glycerol trilinolenate, or glycerol trioleate instead of DDD and it was found that this activity was increased with the increasing number of double bonds in the structure. Furthermore, the same type of experiment was carried out using a lipid-soluble radical initiator, 2,2'-azobisisobutyronitrile and the similar result was obtained. These results indicated that a highly polyunsaturated fatty acid might act as an antioxidant in an emulsion system oxidized by an azo compound. PMID:21099140

Gotoh, Naohiro; Noguchi, Yosuke; Ishihara, Akiko; Yamaguchi, Kaita; Mizobe, Hoyo; Nagai, Toshiharu; Otake, Ikuko; Ichioka, Kenji; Wada, Shun

2010-01-01

342

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

NASA Astrophysics Data System (ADS)

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 ?| < 3.0 (where ? is the track angle with respect to the perpendicular to the emulsion film), while existing systems have an angular acceptance limited to |tan ?| < 0.6. The automatic scanning for such a large angle track in nuclear 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 ? decay candidates due to hadronic interactions will be reduced by a better detection of the emitted nuclear fragments.

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

2013-01-01

343

Yielding and Flow in Adhesive and Nonadhesive Concentrated Emulsions  

NASA Astrophysics Data System (ADS)

The nonlinear rheological response of soft glassy materials is addressed experimentally by focusing on concentrated emulsions where interdroplet attraction is tuned through varying the surfactant content. Velocity profiles are recorded using ultrasonic velocimetry simultaneously to global rheological data in the Couette geometry. Our data show that nonadhesive and adhesive emulsions have radically different flow behaviors in the vicinity of yielding: while the flow remains homogeneous in the nonadhesive emulsion and the Herschel-Bulkley model for a yield stress fluid describes the data very accurately, the adhesive system displays shear localization and does not follow a simple constitutive equation, suggesting that the mechanisms involved in yielding transitions are not universal.

Bécu, Lydiane; Manneville, Sébastien; Colin, Annie

2006-04-01

344

Yielding and flow in adhesive and nonadhesive concentrated emulsions.  

PubMed

The nonlinear rheological response of soft glassy materials is addressed experimentally by focusing on concentrated emulsions where interdroplet attraction is tuned through varying the surfactant content. Velocity profiles are recorded using ultrasonic velocimetry simultaneously to global rheological data in the Couette geometry. Our data show that nonadhesive and adhesive emulsions have radically different flow behaviors in the vicinity of yielding: while the flow remains homogeneous in the nonadhesive emulsion and the Herschel-Bulkley model for a yield stress fluid describes the data very accurately, the adhesive system displays shear localization and does not follow a simple constitutive equation, suggesting that the mechanisms involved in yielding transitions are not universal. PMID:16712042

Bécu, Lydiane; Manneville, Sébastien; Colin, Annie

2006-04-03

345

High-throughput Microsphere Encapsulation in Emulsion Droplets by Electrospray  

NASA Astrophysics Data System (ADS)

Colloidal clusters generated through emulsion encapsulation and evaporation open up the possibilities for assembly of complex crystal structures. Encapsulation in monodisperse emulsion droplets facilitates higher yield of identical clusters as building blocks. We utilize electrospray in an oil-in-water co-flow fluidic device to generate uniform emulsion droplets in micron size and at the rate of ten thousand droplets per second. We investigate the effect of applied voltage, flow rate and the conductivity of liquid on the droplet formation. We further show that incorporation of microspheres into the inner oil fluid enables the encapsulation and formation of clusters.

Chen, Wuen-Shiu; Lin, Keng-Hui

2008-03-01

346

Heavy-oil-emulsion pipeline tests meet targets  

SciTech Connect

Field trials with the Transoil emulsion technology to produce bitumen-in-water emulsions for pipeline transportation met all objectives set by the Transoil group for parameters of time, flow, and emulsion quality. The Transoil group consists of BP Canada Inc., AEC Pipelines (division of Alberta Energy Co. Ltd.), and BP Canadian Holdings Ltd. Presented here are the details of the field trials conducted at the BP Canada-operated Wolf Lake project, 55 km north of Bonnyville, Alta., during the summer and fall 1987 and winter 1988.

Hardy, W.A.; Sit, S.P.; Stockwell, A.

1989-03-06

347

Superhydrophobic cellulose-based bionanocomposite films from Pickering emulsions  

NASA Astrophysics Data System (ADS)

Inherently superhydrophobic and flexible cellulose-based bionanocomposites were fabricated from solid stabilized (Pickering) emulsions. Emulsions were formed by dispersing cyclosiloxanes in water stabilized by layered silicate particles and were subsequently modified by blending into a zinc oxide nanofluid. The polymer matrix was a blend of cellulose nitrate and fluoroacrylic polymer (Zonyl 8740) precompatibilized in solution. Coatings were spray cast onto aluminum substrates from polymer blends dispersed in modified Pickering emulsions. No postsurface treatment was required to induce superhydrophobicity. Effect of antiseptic additives on bionanocomposite superhydrophobicity is also discussed. Replacing cellulose nitrate with commercial liquid bandage solutions produced identical superhydrophobic coatings.

Bayer, Ilker S.; Steele, Adam; Martorana, Philip J.; Loth, Eric; Miller, Lance

2009-04-01

348

Use of demulsifying mixtures for breaking petroleum emulsions  

SciTech Connect

This invention relates to an emulsion-breaking composition comprising about 70 to 99.8% by weight of at least one silicon-free demulsifier, and about 0.2 to 30% by weight of a mixed polyoxyalkylene-polysiloxane block polymerizate, the polyoxyalkylene blocks of which have a molecular weight of about 500 to 4000 and are composed of polyoxyethylene polyoxypropylene blocks in a weight ratio of 40 to 60 to 100:0, and the polysiloxane blocks of which contain 3 to 50 silicon atoms per block. The invention also includes a process for breaking emulsions using the novel emulsion-breaking

Hoffmann, H.; Koerner, G.; Rossmy, G.; Theile, H.; Zaske, P.

1980-01-15

349

Balloon-borne gamma-ray telescope with nuclear emulsion  

NASA Astrophysics Data System (ADS)

We are planning to observe cosmic gamma-ray in the energy range 10MeV to 100GeV by balloon-borne gamma-ray telescope with nuclear emulsion. Nuclear emulsion is a precise tracker. By detecting starting point of electron pair, gamma-ray direction can be determined precisely (1.4mrad@1-2GeV). This is much better than Fermi Gamma-ray Space Telescope launched June 2008. Now we are developing the gamma-ray telescope with nuclear emulsion and are planning to observe by balloon flight. Overview and status of our telescope is introduced in this presentation.

Takahashi, Satoru; Aoki, Shigeki; Fukuda, Tsutomu; Hamada, Kaname; Hara, Toshio; Iyono, Atsushi; Kawada, Jiro; Kazuyama, Masashi; Kodama, Koichi; Komatsu, Masahiro; Koshiba, Shinichiro; Kubota, Hirotaka; Miyamoto, Seigo; Miyanishi, Motoaki; Mor-Ishima, Kunihiro; Naganawa, Naotaka; Naka, Tatsuhiro; Nakamura, Mitsuhiro; Nakano, Toshiyuki; Niwa, Kimio; Nonoyama, Yoshiaki; Ozaki, Keita; Rokujo, Hiroki; Sako, Takashi; Sato, Os-Amu; Sato, Yoshihiro; Suzuki, Kazuya; Suzuki, Atsumu; Takahashi, Satoru; Tezuka, Ikuo; Yoshida, Junya; Yoshioka, Teppei

350

Demulsification of bitumen emulsions using salts of poly (tertiaryamino) polyurethanes  

SciTech Connect

A process for recovering bitumen from oil-in-water (O/W) emulsions is disclosed wherein water-soluble demulsifiers are used. These demulsifiers are salts of poly (tertiary amino) polyurethanes prepared by the reaction of polyisocyanates with diols containing at least one tertiary amino group which reaction product is then reduced in pH until water solubility is attained. To resolve the bituminous petroleum emulsions, the process is carried out between 25/sup 0/ and 160/sup 0/C. wherein the demulsifier of the invention is contacted with the bituminous emulsion.

McCoy, D.R.

1983-09-06

351

A microfluidic platform for formation of double-emulsion droplets  

Microsoft Academic Search

A new method for actively controlling the number of internal droplets of water-in-oil-in-water (W\\/O\\/W) double-emulsion droplets\\u000a was demonstrated. A new microfluidic platform for double-emulsion applications has been developed, which integrates T-junction\\u000a channels, moving-wall structures, and a flow-focusing structure. Inner water-in-oil (W\\/O) single-emulsion droplets were first\\u000a formed at a major T-junction. Then the droplets were sub-divided into smaller uniform droplets by

Kin-Lok Lao; Jung-Hao Wang; Gwo-Bin Lee

2009-01-01

352

Biofilm Formation in Microscopic Double Emulsion Droplets  

NASA Astrophysics Data System (ADS)

In natural, medical, and industrial settings, there exist surface-associated communities of bacteria known as biofilms. These highly structured films are composed of bacterial cells embedded within self-produced extracellular matrix, usually composed of exopolysaccharides, proteins, and nucleic acids; this matrix serves to protect the bacterial community from antibiotics and environmental stressors. Here, we form biofilms encapsulated within monodisperse, microscopically-sized double emulsion droplets using microfluidics. The bacteria self-organize at the inner liquid-liquid droplet interfaces, multiply, and differentiate into extracellular matrix-producing cells, forming manifold three-dimensional shell-within-a-shell structures of biofilms, templated upon the inner core of spherical liquid droplets. By using microfluidics to encapsulate bacterial cells, we have the ability to view individual cells multiplying in microscopically-sized droplets, which allows for high-throughput analysis in studying the genetic program leading to biofilm development, or cell signaling that induces differentiation.

Chang, Connie; Weitz, David

2012-02-01

353

Stability of cellulose lyotropic liquid crystal emulsions  

NASA Astrophysics Data System (ADS)

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.

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

2005-12-01

354

Emulsion chamber observations of primary electrons  

NASA Astrophysics Data System (ADS)

Recent observations of high-energy primary electrons, using emulsion chambers exposed by balloon (Nishimura et al., 1980), have been extended to a net exposure factor of about 7 sq m-sr-day. This is more than an order of magnitude greater than that obtained by other experimental techniques. The propagation of electrons is based on a model, similar to the leaky box model, which makes it possible to obtain statistically significant measurements of the electron spectrum in the TeV range. The data indicate a depression of the spectrum beyond approximately 1 TeV; this depression of high energy electrons above 1 TeV reflects the acceleration mechanism at the source.

Nishimura, J.; Fujii, M.; Taira, T.; Aizu, E.; Nomura, Y.; Kobayashi, T.; Niu, K.; Nishio, A.; Golden, R. L.; Koss, T. A.

355

Active Emulsions: Synchronization of Chemical Oscillators  

NASA Astrophysics Data System (ADS)

We explore the dynamical behavior of emulsions consisting of nanoliter volume droplets of the oscillatory Belousov-Zhabotinsky (BZ) reaction separated by a continuous oil phase. Some of the aqueous BZ reactants partition into the oil leading to chemical coupling of the drops. We use microfluidics to vary the size, composition and topology of the drops in 1D and 2D. Addition of a light sensitive catalyst to the drops and illumination with a computer projector allows each drop to be individually perturbed. A variety of synchronous regimes are found that systematically vary with the coupling strength and whether coupling is dominated by activatory or inhibitory species. In 1D we observe in- and anti-phase oscillations, stationary Turing patterns in which drops stop oscillating, but form spatially periodic patterns of drops in the oxidized and reduced states, and more complex combinations of stationary and oscillatory drops. In 2D, the attractors are more complex and vary with network topology and coupling strength. For hexagonal lattices as a function of increasing coupling strength we observe right and left handed rotating oscillations, mixed oscillatory and Turing states and finally full Turing states. Reaction -- diffusion models based on a simplified description of the BZ chemistry and diffusion of messenger species reproduce a number of the experimental results. For a range of parameters, a simplified phase oscillator model provides an intuitive understanding of the complex synchronization patterns. [4pt] ``Coupled oscillations in a 1D emulsion of Belousov--Zhabotinsky droplets,'' Jorge Delgado, Ning Li, Marcin Leda, Hector O. Gonzalez-Ochoa, Seth Fraden and Irving R. Epstein, Soft Matter, 7, 3155 (2011).

Fraden, Seth

2012-02-01

356

Preparation of polymer particles having ethyleneurea groups at their surfaces by emulsifier-free seeded emulsion polymerization and wet adhesion of its emulsion film  

Microsoft Academic Search

Polymer emulsion having ethyleneurea groups at particle surfaces was produced by emulsifier-free seeded emulsion copolymerization of n-butyl methacrylate (BMA) and methacrylamide ethylethyleneurea (EU) with poly(BMA) seed particles utilizing the starved-fed monomer addition method. This emulsion film, prepared by casting the polymer emulsion on an alkyd resin plate, had a superior adhesion in water, as well as on stainless steel. Such

Masayoshi Okubo; Yasuyuki Kagawa; Mitsuo Matsuda; Akinori Terada

2003-01-01

357

Water-in-carbon dioxide emulsions: Formation and stability  

SciTech Connect

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.

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

1999-09-28

358

Chitosan macroporous foams obtained in highly concentrated emulsions as templates.  

PubMed

Emulsion templating is an effective route for the preparation of macroporous polymer foams, with well-defined pore structures. This kind of material is usually obtained by polymerization or crosslinking in the external phase of highly concentrated emulsions. The present article describes the synthesis of macroporous foams based on a cationic polymer, chitosan, crosslinked with genipin, a natural crosslinker. The phase behavior was used to study the influence of chitosan on surfactant self-aggregation. Hexagonal and lamellar liquid crystalline structures could be obtained in the presence of chitosan, and polymer did not greatly influence the geometric lattice parameters of these self-aggregates. O/W highly concentrated emulsions were obtained in the presence of chitosan in the continuous phase, which allowed reducing both droplet size and polydispersity. The emulsions were stable during the time required for crosslinking, obtaining macroporous foams with high pore volume and degree of crosslinking. PMID:24011788

Miras, Jonathan; Vílchez, Susana; Solans, Conxita; Esquena, Jordi

2013-08-12

359

Aging mechanisms of perfluorocarbon emulsions using image analysis.  

PubMed

The aging mechanisms of perfluorocarbon emulsions were investigated using image analysis. Oil-in-water emulsions of two perfluorocarbons, n-perfluorohexane and perfluorodecalin, were prepared with three emulsifiers, Lecithin, Span 20, and Pluronic F-68. The effect of the temperature and the replacement of water by an aqueous phase consisting of a microbial culture medium were also studied. The emulsions were prepared by sonication and their stability was followed through analysis of the evolution of mean droplet size. The results indicate that the stability of perfluorocarbon in water emulsions depends on all the parameters investigated and that two aging mechanisms, coalescence and molecular diffusion, may take place. Analysis of the evolution of the mean droplet size during long time periods indicate that coalescence is more common than previously reported for these systems and seems to be favored by a temperature increase. PMID:15848420

Freire, Mara G; Dias, Ana M A; Coelho, Maria A Z; Coutinho, João A P; Marrucho, Isabel M

2005-06-01

360

Physical and Chemical Characteristics of High Ph Intralipid Fat Emulsions.  

National Technical Information Service (NTIS)

Intralipid intravenous fat emulsions, that were purposely prepared to have high pH, were broken down into oil and water phases. The neutral and polar lipids and water soluble materials were examined by chromatographic procedures. Extreme differences were ...

N. Pelick J. H. Tinker J. M. Steim

1965-01-01

361

Dehydration of oil waste emulsions by means of flocculants  

SciTech Connect

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.

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

1995-05-01

362

Nano-emulsions and nanocapsules by the PIT method: An investigation on the role of the temperature cycling on the emulsion phase inversion  

Microsoft Academic Search

This paper focuses on the phenomenological understanding of temperature cycling process, applied to the phase inversion temperature (PIT) method. The role of this particular thermal treatment on emulsions phase inversion, as well as its ability to generate nano-emulsions have been investigated. In order to propose a general study, we have based our investigations on a given formulation of nano-emulsions classically

Nicolas Anton; Pascal Gayet; Jean-Pierre Benoit; Patrick Saulnier

2007-01-01

363

Factors in the occlusivity of aqueous emulsions. Influence of humectants  

Microsoft Academic Search

In this work, factors controlling occlusivity of emulsions when humectants are added were studied. Emulsions were prepared from perhydrosqualene (P.H.S.) and mineral oil using ester and ether non-ionic surfactants having various HLB values in the presence of sodium 5-pyrrolidone-2-carboxylate, sodium lactate, and urea each at concentrations of 0, 0.62, 1.25, 2.5, 3.75, and 5%. Physicochemical parameters analyzed included isotropic oily

T. H. CHOUDHURY; J. P. MARTY; A. M. ORECCHIONI

364

Polymer functionalized submicrometric emulsions as potential synthetic DNA vectors  

Microsoft Academic Search

Triglyceride-based emulsions were first prepared by a solvent displacement procedure which was modified to achieve their functionalization by surface deposition of various amphiphilic comb-like copolymers. These emulsions have been characterized as regards to hydrodynamic particle size and surface charges using dynamic light scattering and electrophoretic mobility measurements. The adsorption isotherms of a polydT15 oligonucleotide and a model plasmid showed that

Thomas Trimaille; Carole Chaix; Christian Pichot; Thierry Delair

2003-01-01

365

Soft X-ray spectromicroscopy on solid-stabilized emulsions  

Microsoft Academic Search

Oil–water emulsions stabilized by solids have been imaged with sub-100?nm spatial resolution and analyzed spectroscopically\\u000a using a scanning transmission X-ray microscope. The emulsions are stabilized by particle heterocoagulate cages surrounding\\u000a the oil droplets. These cages form due to the interaction of negatively charged clay mineral particles (sodium montmorillonite,\\u000a Wyoming) and positively charged particles of calcium\\/aluminum layered double hydroxide (LDH). The

U. Neuhäusler; S. Abend; C. Jacobsen; G. Lagaly

1999-01-01

366

Generation of colloidal granules and capsules from double emulsion drops  

NASA Astrophysics Data System (ADS)

Assemblies of colloidal particles are extensively used in ceramic processing, pharmaceuticals, inks and coatings. In this project, the aim was to develop a new technique to fabricate monodispersed colloidal assemblies. The use of microfluidic devices and emulsion processing allows for the fabrication of complex materials that can be used in a variety of applications. A microfluidic device is used to create monodispersed water/oil/water (w/o/w) double emulsions with interior droplets of colloidal silica suspension ranging in size from tens to hundreds of microns. By tailoring the osmotic pressure using glycerol as a solute in the continuous and inner phases of the emulsion, we can control the final volume size of the monodispersed silica colloidal crystals that form in the inner droplets of the double emulsion. Modifying the ionic strength in the colloidal dispersion can be used to affect the particle-particle interactions and crystal formation of the final colloidal particle. This w/o/w technique has been used with other systems of metal oxide colloids and cellulose nanocrystals. Encapsulation of the colloidal suspension in a polymer shell for the generation of ceramic-polymer core-shell particles has also been developed. These core-shell particles have spawned new research in the field of locally resonant acoustic metamaterials. Systems and chemistries for creating cellulose hydrogels within the double emulsions have also been researched. Water in oil single emulsions and double emulsions have been used to create cellulose hydrogel spheres in the sub-100 micron diameter range. Oil/water/oil double emulsions allow us to create stable cellulose capsules. The addition of a second hydrogel polymer, such as acrylate or alginate, further strengthens the cellulose gel network and can also be processed into capsules and particles using the microfluidic device. This work could have promising applications in acoustic metamaterials, personal care products, pharmaceuticals, and agricultural applications, among others.

Hess, Kathryn S.

367

Chemical demulsification of tanker crude emulsions. Memorandum report  

SciTech Connect

The chemical demulsification of tanker crude emulsions was studied as a function of oil type (light vs. heavy crude), demulsifier concentrations, and temperature. Aerosol OT shows promise as a chemical demulsifier of tanker crude emulsions provided that ambient temperatures are not too cold and that an appropriate concentration range is used for specific oil. The evaporation rates and viscosities of the six crudes studied are also reported in the text.

Little, R.C.

1980-02-13

368

The role of non-ionic surfactants in emulsion stability  

Microsoft Academic Search

The role of W, aryl polyglycol ester, and G 100P, an alkyl phenyl polyglycol ether, on the stability of dilute petroleum ether in water\\u000a emulsion has been studied in the light of the DLVO theory. The zeta potential of the emulsions flocculated by varying concentrations\\u000a of different electrolytes, viz., potassium nitrate, strontium nitrate and aluminium ammonium sulphate, has been calculated

A. Kamel; V. Sabet; H. Sadek; S. N. Srivastava

369

Flow of oil–water emulsions through a constricted capillary  

Microsoft Academic Search

The flow of oil-in-water emulsions through quartz micro-capillary tubes was analyzed experimentally. The capillaries were used as models of connecting pore-throats between adjacent pore body pairs in high-permeability media. Pressure drop between the inlet and outlet ends of the capillary was recorded as a function of time, for several values of the volumetric flow rate. Several distinct emulsions were prepared

S. Cobos; M. S. Carvalho; V. Alvarado

2009-01-01

370

PREPARATION OF INHALABLE PROTEIN PARTICLES BY SCF-EMULSION DRYING  

Microsoft Academic Search

In this study, an new patented emulsion drying technique using high pressure carbon dioxide was employed for the generation of fine protein particles. Water-in-oil (W\\/O) emulsion droplets were sprayed into a continuous feed of high pressure carbon dioxide. Protein particles precipitated as a result of expansion of the droplets and removal of water by the CO2-organic solvent mixture. Model enzymes

Jennifer JUNG; Fabrice LEBOEUF; Michel PERRUT

371

Restricted diffusion: An effective tool to investigate food emulsions  

Microsoft Academic Search

We present a method to extract from pulsed-field-gradient spin-echo NMR measurements, the droplet size distributions in emulsions and the self-diffusion coefficient of the dispersed phase. The method is applied to butter and water\\/extra-virgin olive oil emulsions. The droplet size distributions are in agreement with optical microscopy analysis. The butter size distribution is a log-normal form and the effect of the

G. Colafemmina; G. Palazzo; A. Ceglie; L. Ambrosone; G. Cinelli; V. Di Lorenzo

372

Mechanism of detonation of emulsion explosives with microballoons  

Microsoft Academic Search

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

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

2008-01-01

373

Transitional emulsion polymerisation: Zero-one to pseudo-bulk  

Microsoft Academic Search

The transitional behaviours of emulsion polymerisation for styrene and butyl acrylate (BA) monomers from zero-one to pseudo-bulk regime were mechanistically investigated. A dynamic mathematical model, which incorporates cross-over mechanism from zero-one to pseudo-bulk kinetics was developed for emulsion polymerisation and compared with experimental data for conversion, particle size and molar mass. Particles smaller than cross-over size follow zero-one kinetics and

Simon M. Jung; Vincent G. Gomes

2011-01-01

374

Chemical demulsification of petroleum emulsions using oil-soluable demulsifiers  

Microsoft Academic Search

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

Mark A. Krawczyk; Darsh T. Wasan; Chandrashekar Shetty

1991-01-01

375

Synthesis of mesoporous silica particles prepared by using multiple emulsion  

Microsoft Academic Search

The spherical silica particles with meso- and macropores at the surface and inside of particles were prepared in the hexane\\/water\\/n-decyl alcohol multiple-emulsion. Also micrometer-sized hollow silica particles could be prepared by controlling the viscosity of the aqueous phase in W\\/O emulsion with polyethylene glycol (PEG). The morphology of silica particles was influenced by the concentration of PEG, HPC polymer and

Chul Oh; Jae-Hyung Park; Seung-il Shin; Seung-Geun Oh

2003-01-01

376

Freeze–thaw stability of water-in-oil emulsions  

Microsoft Academic Search

Factors influencing water-in-oil emulsion stability during freeze\\/thaw-cycling, namely interfacial crystallization vs. network crystallization and the sequence of crystallization events (i.e., dispersed vs. continuous phase or vice versa), are assessed. We show that destabilization is most apparent with a liquid-state emulsifier and a continuous oil phase that solidifies prior to the dispersed phase. Emulsions stable to F\\/T-cycling are obtained when the

S. Ghosh; D. Rousseau

2009-01-01

377

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 Astrophysics Data System (ADS)

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 1014 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.

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

1997-01-01

378

Droplet-based microfluidics and the dynamics of emulsions  

NASA Astrophysics Data System (ADS)

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)

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

2012-02-01

379

Fat Overload Syndrome After the Rapid Infusion of SMOFlipid Emulsion.  

PubMed

Fat overload syndrome is a well-known complication of intravenous lipid emulsion therapy. It is characterized by headaches, fever, jaundice, hepatosplenomegaly, respiratory distress, and spontaneous hemorrhage. Other symptoms include anemia, leukopenia, thrombocytopenia, low fibrinogen levels, and coagulopathy. Several reports in the literature describe fat overload syndrome caused by rapid infusion of lipid emulsions, all with soybean-based lipid emulsions. We report fat overload syndrome in a 2-year-old girl with short bowel syndrome on home parenteral nutrition. Fat overload syndrome occurred as a result of accidental, very rapid infusion of a 20% soy oil, medium-chain triglyceride, olive and fish oil-based lipid emulsion (SMOFlipid) that showed the same complications seen with an earlier lipid emulsion (Intralipid). The patient was successfully treated with supportive care combining fluid infusion, transfusion of platelets, and substitution of serum albumin (0.5 g/kg/d) and fresh-frozen plasma (10 mL/kg). In the next couple of days, she received extra platelets, erythrocyte transfusion, and filgrastim (Neupogen; 5 µg/kg/d) due to a very low leukocyte count. To the best of our knowledge, this is the first case of fat overload syndrome caused by SMOFlipid emulsion described in the literature. PMID:23520135

Hojsak, Iva; Kolacek, Sanja

2013-03-21

380

Formulation, stability and degradation kinetics of intravenous cinnarizine lipid emulsion.  

PubMed

Cinnarizine was loaded in the lipid emulsion to develop an intravenous formulation with good physical and chemical stability. High-pressure homogenization was used to prepare the lipid emulsion. The factors influencing the stability of cinnarizine lipid emulsion, such as different drug loading methods, pH, temperature, sterilization methods and sterilization time were monitored by high-performance liquid chromatograph. The degradation of cinnarizine in aqueous solution and lipid emulsion both followed apparent first-order kinetics. A possible degradation mechanism was postulated by the bell-shaped pH-rate profile of cinnarizine. Localization of the drug in the interfacial lecithin layer significantly improved the chemical stability of cinnarizine and its stabilizing mechanism was thoroughly discussed and proved. The activation energy of cinnarizine in lipid emulsion was calculated to be 51.27 kJ/mol which was similar to that in aqueous solution. This indicates that the stabilizing effect of the drug carrier on cinnarizine was not an alteration of the degradation reaction. In addition, shelf-life of cinnarizine in lipid emulsion was estimated to be 1471.6 days at 4 degrees C, which is much longer compared with 19.8 days in aqueous solution. The final products were stable enough to resist a 121 degrees C rotating steam sterilization for 15 min. PMID:19429300

Shi, Shuai; Chen, Hao; Cui, Yue; Tang, Xing

2009-02-20

381

Characterization of paraffin oil emulsions stabilized by hydroxypropyl methylcellulose.  

PubMed

To study the relationship between emulsion stability and polymer emulsifier concentration, the preparation of paraffin oil emulsions by hydroxypropyl methylcellulose (HPMC) was carried out with HPMC concentrations below the overlapping concentration (C(*)) of HPMC. The stability of the emulsions incorporating HPMC was investigated by measuring the creaming velocity, volume fraction of emulsified paraffin oil, oil droplet size, and some rheological responses such as the stress-strain sweep curve and strain and frequency dependences of dynamic viscoelastic moduli. The paraffin oil was almost emulsified by HPMC above C(*)/20: the volume fraction of paraffin oil in the emulsion was higher than 0.72. Increasing in the HPMC concentration led to decreases in both the average oil droplet size and creaming velocity and an increase in the yield stress. All emulsions behaved as solid-like viscoelastic matter. Additionally, the measured dynamic storage moduli were compared with those calculated from a relationship based on functions of the volume fraction of oil in the emulsions and Laplace pressure; good agreement between the measured and calculated moduli was obtained. On the other hand, at HPMC concentrations below C(*)/50, the emulsified paraffin oil became unstable and the oil and the HPMC solution eventually separated. PMID:22138268

Futamura, Taiki; Kawaguchi, Masami

2011-11-15

382

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

NASA Astrophysics Data System (ADS)

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, with droplet size ranging from 0.3to40?m , in a wide-gap Couette geometry. We couple macroscopic rheometric experiments and local velocity measurements through magnetic resonance imaging (MRI) techniques. As concentration heterogeneities are expected in the wide-gap Couette flows of multiphase materials, we also 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 in wide-gap Couette flows, 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. The existence of a constitutive law accounting for all flows contrasts with previous results obtained within a microchannel by Goyon [Nature (London) 454, 84 (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 Bécu [Phys. Rev. Lett. 96, 138302 (2006)]. We also evidence the existence of discrepancies between a perfect Herschel-Bulkley behavior and the observed local behavior 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.

Ovarlez, G.; Rodts, S.; Ragouilliaux, A.; Coussot, P.; Goyon, J.; Colin, A.

2008-09-01

383

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

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

384

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

Code of Federal Regulations, 2010 CFR

...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...

2009-07-01

385

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

Code of Federal Regulations, 2010 CFR

...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...

2010-07-01

386

Energy spectrum of cosmic-ray iron nucleus observed with emulsion chamber  

NASA Astrophysics Data System (ADS)

Energy spectrum of cosmic-ray Fe-nucleus has been measured from 4 GeV per nucleon to beyond 100 GeV per nucleon. The data were obtained using emulsion chambers on a balloon from Sanriku, Japan. The energies were estimated by the opening angle method after calibrated using 1.88 GeV per nucleon Fe collisions. The spectrum of Fe is approximately E-2.5 in the range from 10 to 200 GeV per nucleon. This result is in good agreement with those of other experiments.

Sato, Y.; Shimada, E.; Ohta, I.; Tasaka, S.; Tanaka, S.; Sugimoto, H.; Taira, K.; Tateyama, N.

1985-08-01

387

High energy factorization in nucleus-nucleus collisions III. Long range rapidity correlations  

SciTech Connect

We obtain a novel result in QCD for long range rapidity correlations between gluons produced in the collision of saturated high energy hadrons or nuclei. This result, obtained in a high energy factorization framework, provides strong justification for the Glasma flux tube picture of coherent strong color fields. Our formalism can be applied to 'near side ridge' events at the Relativistic Heavy Ion Collider and in future studies of long range rapidity correlations at the LHC.

Venugopalan, R.; Gelis, F., Lappi, T.

2009-10-27

388

``Space-time evolution of nucleus-nucleus collisions measured by intensity interferometry''  

NASA Astrophysics Data System (ADS)

New results about the production of multifragment final states and the information content of two-particle correlation functions will be presented. The author acknowledges the collaboration with W. Bauer, D.R. Bowman, N. Carlin, R.T. de Souza, W.A. Friedman, D.E. Fields, W.G. Gong, Y.D. Kim, Kwiatkowski, M.A. Lisa, W.G. Lynch, T. Murakami, G.F. Peaslee, L. Phair, R. Planeta, G. Poggi, S. Pratt, D.P. Sanderson, M.B. Tsang, V.E. Viola, Jr., H.M. Xu, S.J. Yennello, and F. Zhu.

Gelbke, C. K.

1992-03-01

389

High energy factorization in nucleus-nucleus collisions. III. Long range rapidity correlations  

SciTech Connect

We obtain a novel result in QCD for long range rapidity correlations between gluons produced in the collision of saturated high energy hadrons or nuclei. This result, obtained in a high energy factorization framework, provides strong justification for the Glasma flux tube picture of coherent strong color fields. Our formalism can be applied to 'near side ridge' events at the Relativistic Heavy Ion Collider and in future studies of long range rapidity correlations at the LHC.

Gelis, Francois [Theory Division, PH-TH, Case C01600, CERN, CH-1211, Geneva 23 (Switzerland); Institut de Physique Theorique (URA 2306 du CNRS), CEA/DSM/Saclay, Bat. 774, 91191, Gif-sur-Yvette Cedex (France); Lappi, Tuomas [Institut de Physique Theorique (URA 2306 du CNRS), CEA/DSM/Saclay, Bat. 774, 91191, Gif-sur-Yvette Cedex (France); Venugopalan, Raju [Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)

2009-05-01

390

Exclusive glueball production in high-energy nucleus-nucleus collisions  

SciTech Connect

The cross sections for the glueball candidates in quasireal photon-photon collisions and on central diffraction processes (i.e., double Pomeron exchange) in heavy-ion interactions at the Relativistic Heavy-Ion Collider (RHIC) and the Large Hadron Collider (LHC) are computed. The rates for these distinct production channels are compared, and they may be a fruitful approach to the investigation of glueballs.

Machado, M. V. T. [High Energy Physics Phenomenology Group, High Energy Particle Phenomenology Group - Instituto de Fisica - Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP 91501-970, Porto Alegre, Rio Grande do Sul (Brazil); Silva, M. L. L. da [Centro de Ciencias Fisicas e Matematicas, Departamento de Fisica, Universidade Federal de Santa Catarina, Bairro Trindade. Caixa Postal 476, CEP 88040-970, Florianopolis, Santa Catarina (Brazil)

2011-01-15

391

New Mechanism for Forming Highly Dense Nuclear Matter in Relativistic Nucleus-Nucleus Collisions.  

National Technical Information Service (NTIS)

A reaction mechanism is outlined which already during the penetration phase of the collision provides the conditions for phase transitions with reference to the density. In the framework of this relativistic dynamic model possible first-and second-order p...

H. Iwe

1978-01-01

392

Investigation of Nuclear Matter Properties by Means of High Energy Nucleus-Nucleus Collisions.  

National Technical Information Service (NTIS)

We review recent advances towards an understanding of high density nuclear matter, as created in central collisions of nuclei at high energy. In particular, information obtained for the nuclear matter equation of state will be discussed. The lectures focu...

R. Stock

1985-01-01

393

The concept of a Pauli barrier in nucleus-nucleus scattering  

NASA Astrophysics Data System (ADS)

The influence of partly Pauli-forbidden states on the width of resonances is stuied in the context of the fish bone optical model. A numerical study of ?-? and ?-16O scattering shows that the part of the nonlocal interaction of the model which is due to the partly forbidden states represents a Pauli barrier which inhibits transitions between the inner and asymptotic regions and increases the lifetime of resonances.

Schmid, E. W.; Saito, S.; Fiedeldey, H.

1982-03-01

394

Multiparticle azimuthal correlations of negative pions in nucleus-nucleus collisions  

SciTech Connect

Multiparticle azimuthal correlations of {pi}{sup -} mesons have been studied in dC, HeC, CC, CNe, MgMg, (d, He)Ta, CCu, CTa, and OPb collisions at momentum of 4.2, 4.5 GeV/c per nucleon within the standard transverse momentum analysis method of P. Danielewicz and G. Odyniec. The data were obtained by SKM-200-GIBS and Propane Bubble Chamber Collaborations of JINR. The axis has been selected in the phase space and with respect to this axis {pi}{sup -} meson correlations were observed. The values of the coefficient of the correlations linearly depend on the mass numbers of projectile (A{sub P}) and target (A{sub T}) nuclei. The Quark-Gluon String Model satisfactorily describes the experimental results.

Chkhaidze, L. V., E-mail: ichkhaidze@yahoo.com; Djobava, T. D.; Kharkhelauri, L. L. [Tbilisi State University, High Energy Physics Institute (Georgia); Kladnitskaya, E. N. [Joint Institute for Nuclear Research (Russian Federation)

2012-07-15

395

Ratios of heavy baryons to heavy mesons in relativistic nucleus-nucleus collisions  

SciTech Connect

Heavy baryon/meson ratios {lambda}{sub c}/D{sup 0} and {lambda}{sub b}/B{sup 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 as well as with bounded light diquarks that might exist in the strongly coupled quark-gluon plasma produced in these collisions. Including the contribution from decays of heavy hadron resonances and also that due to fragmentation of heavy quarks that are left in the system after coalescence, the resulting {lambda}{sub c}/D{sup 0} and {lambda}{sub b}/B{sup 0} ratios in midrapidity (|y|{<=}0.5) from central Au+Au collisions at {radical}(s{sub NN})=200 GeV are about a factor of five and ten, respectively, larger than those given by the thermal model, and about a factor of ten and twelve, respectively, larger than corresponding ratios in the PYTHIA model for pp collisions. These ratios are reduced by a factor of about 1.6 if there are no diquarks in the quark-gluon plasma. The transverse momentum dependence of the heavy baryon/meson ratios is found to be sensitive to the heavy quark mass, with the {lambda}{sub b}/B{sup 0} ratio being much flatter than the {lambda}{sub c}/D{sup 0} ratio. The latter peaks at the transverse momentum p{sub T}{approx_equal}0.8 GeV but the peak shifts to p{sub T}{approx_equal}2 GeV in the absence of diquarks.

Oh, Yongseok; Ko, Che Ming [Cyclotron Institute and Physics Department, Texas A and M University, College Station, Texas 77843 (United States); Lee, Su Houng [Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of); Yasui, Shigehiro [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 302-0801 (Japan)

2009-04-15

396

Search for nonintegrally charged projectile fragments in relativistic nucleus-nucleus collisions  

SciTech Connect

Using dioctyl-phthalate--doped CR-39 plastic track detectors with charge resolution sigma/sub Z/roughly-equal0.06e, the authors have made the first dynamic search for fractionally charged particles bound to nuclei. They find, from charge measurements in the first approx.2 cm after production, that no more than 3 x 10/sup -3/ (95% confidence level) of the projectile fragments of 1.85-GeV/u /sup 40/Ar interactions with 10< or =Z<18 have charges differing from an integer by as much as 0.3e. This rules out explanations of anomalons based on models in which the anomalons have nonintegral charge in such charge range.

Price, P.B.; Tincknell, M.L.; Tarle, G.; Ahlen, S.P.; Frankel, K.A.; Perlmutter, S.

1983-02-21

397

Search for Nonintegrally Charged Projectile Fragments in Relativistic Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

Using dioctyl-phthalate-doped CR-39 plastic track detectors with charge resolution ?Z~0.06e, the authors have made the first dynamic search for fractionally charged particles bound to nuclei. They find, from charge measurements in the first ~ 2 cm after production, that no more than 3 × 10-3 (95% confidence level) of the projectile fragments of 1.85-GeV/u 40Ar interactions with 10<=Z<18 have charges differing from an integer by as much as 0.3e. This rules out explanations of anomalons based on models in which the anomalons have nonintegral charge in such charge range.

Price, P. B.; Tincknell, M. L.; Tarlé, G.; Ahlen, S. P.; Frankel, K. A.; Perlmutter, S.

1983-02-01

398

Neutral pion production in nucleus-nucleus collisions at 158 and 200 GeV/nucleon  

SciTech Connect

Two years ago, at the 12th Winter Workshop on Nuclear Dynamics held here in Snowbird, the authors presented WA80 limits on direct photon production in 200-GeV {sup 32}S + Au collisions. It was found that the results were consistent (within 1{sigma}) with the absence of an excess of photons over those that can be accounted for by the two-photon decay branches of {pi}{sup 0} and {eta} mesons and by the small photon contributions from other radiative decays. They are in the process of finalizing the direct-photon production results from collisions of lead nuclei at 158 GeV/nucleon. The author briefly discusses the status of the analysis and gives some preliminary results at the end of this talk. However, most of this presentation is concerned with a very different aspect of the photon measurements: distributions of neutral pions. In contrast to direct photons which probe initial collision conditions, hadrons, such as neutral pions, interact strongly and decouple late in the reaction evolution and, thus, provide information concerning the system at freeze out. Transverse momentum spectra at low and intermediate p{sub T} relate to thermodynamic and hydrodynamic descriptions of the hot, dense systems. In addition, the high-p{sub T} region reflects the hard-scattering regime and may help one understand initial-state particle production by forming a bridge to proton-proton and proton-nucleus results. It follows that it is essential that the {pi}{sup 0} measurements cover a large p{sub T} range.

Plasil, F.; WA80 Collaboration; WA98 Collaboration

1998-02-01

399

Relativistic nucleus-nucleus collisions: Zone of reactions and space-time structure of fireball  

SciTech Connect

A zone of reactions is determined and then exploited as a tool in studying the space-time structure of an interacting system formed in a collision of relativistic nuclei. The time dependence of the reaction rates integrated over spatial coordinates is also considered. Evaluations are made with the help of the microscopic transport model UrQMD. The relation of the boundaries of different zones of reactions and the hypersurfaces of sharp chemical and kinetic freeze-outs is discussed.

Anchishkin, D. [Bogolyubov Institute for Theoretical Physics, Kiev 03680 (Ukraine); Muskeyev, A.; Yezhov, S. [Taras Shevchenko Kiev National University, Kiev 03022 (Ukraine)

2010-03-15

400

Nucleus-Nucleus Bremsstrahlung from Scattering Angle Selected Cl-Sn Collisions.  

National Technical Information Service (NTIS)

Continuum X rays above the K lines of Sn were measured at 90 and 0 deg angle relative to the incident beam direction in coincidence with C1 projectiles scattered at very large laboratory angles between 8 and 164 deg. By varying the isotope mass of the pro...

G. Gaukler G. Nolte R. Schuch

1986-01-01

401

Pionic freeze-out hypersurfaces in relativistic nucleus-nucleus collisions  

NASA Astrophysics Data System (ADS)

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.

Anchishkin, D.; Vovchenko, V.; Csernai, L. P.

2013-01-01

402

Excited State Populations and Temperature Measurements in Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

Two particle correlation functions and excited state populations were measured for the ^129Xe+^natCu reaction at 30 MeV/A and ^197Au+^197Au reaction at 35 MeV/A with Miniball detectors and the high resolution Multics array. The temperatures were extracted with impact parameter selection and compared with sequential decay calculations.

Huang, M. J.; Lynch, W. G.; Dinius, J. D.; Gaff, S. J.; Gelbke, C. K.; Glasmacher, T.; Kunde, G. J.; Martin, L.; Montoya, C. P.; Tsang, M. B.; Colonna, N.; Bruno, M.; D'Agostino, M.; Fiandri, M. L.; Mastinu, P. F.; Gramegna, F.; Iori, I.; Moroni, A.; Petruzzelli, F.; Margagliotti, G. V.; Milazzo, P. M.; Rui, R.; Vannini, G.; Ferrero, A.

1996-05-01

403

Pion-nucleon scattering and pion production in nucleon-nucleon and nucleus-nucleus collisions  

Microsoft Academic Search

Lecture notes are presented on the following: (1) basic aspects of ..pi..N interactions (properties of pions and nucleons, SU(3) and SU(6) classification phenomenology of ..pi..N scattering ((3.3) resonance; phase shift analysis, and bag model approach to ..pi..N); (2) pion production and absorption in the two nucleon system (NN ..-->.. NN..pi.. (isobar model) and ..pi..d reversible NN (existence of dibaryon resonances));

Dover

1982-01-01

404

Photoproduction of Quarkonium in Proton-Proton and Nucleus-Nucleus Collisions  

NASA Astrophysics Data System (ADS)

We discuss the photoproduction of ? and J/? at high energy p¯p, pp, and heavy ion colliders. We predict large rates in p¯p interactions at the Fermilab Tevatron and in pp and heavy ion interactions at the CERN Large Hadron Collider. The J/? is also produced copiously at the Relativistic Heavy Ion Collider. These reactions can be used to study the gluon distribution in protons and heavy nuclei. We also show that the different CP symmetries of the initial states lead to large differences in the transverse momentum spectra of mesons produced in p¯p vs pp collisions.

Klein, Spencer R.; Nystrand, Joakim

2004-04-01

405

Rapidity signatures of phase transition in high energy nucleus-nucleus collisions  

NASA Astrophysics Data System (ADS)

The interaction of a 5-TeV Si nucleus with a Br or Ag target is simulated on the basis of the theoretical calculations of Elbert and Stanev (1983) and the parameterization of Stenlund and Otterlund (1982). The results are compared with observations of such a collision in the balloon-borne high-energy cosmic-ray data of Burnett et al. (1983), and an excess of particles with pseudorapidities greater than 3 is found. It is shown that this excess can be attributed to the formation of a phase-transition fireball in the Si nucleus.

Stanev, T.

406

Modelling the effects of (green) antifungals, droplet size distribution and temperature on mould outgrowth in water-in-oil emulsions.  

PubMed

Prevention of fungal spoilage is a key microbiological issue for the shelf life of fat spreads. Our aim was to assess and model the scope of (natural) antimicrobials for extending shelf life of spreads (water-in-oil emulsions). Production conditions were established to make 60% model fat spreads with reproducible droplet size distributions. The mould vulnerabilities ranged from 1 to 20 weeks. The system allowed feasibility testing of lytic enzymes (Novozym 234) and LMW compounds against Penicillium roqueforti, a key-spoilage mould. The action of Novozym 234, carvacrol, undecanol and dihydrocarveol was benchmarked against sorbate and preservative-free controls under ambient and chilled conditions. Novozym 234 was ineffective to prevent outgrowth of P. roqueforti. Carvacrol, undecanol and dihydrocarveol had limited effects on shelf-life extension compared to sorbate. Fungal growth boundaries of (un-)preserved spreads were modelled. The emulsion droplet size distribution (DSD) was first captured in a mechanistic parameter DSD-I (I = Influence). DSD-I was a move away from the mean droplet diameter D3,3 as sole quantitative droplet-size distribution parameter for mould susceptibility of emulsions. DSD-I is a combination of available water droplets and surface area to initiate and sustain fungal outgrowth. Followup experiments showed that modelling D3,3 and distribution width (e(sigma)) instead of DSD-I gave better results for emulsions with high e(sigma). Empirical predictive models were subsequently developed for the effects of D3,3, e(sigma) and undissociated sorbic acid (HSO) on the shelf life of emulsions. PMID:11518432

ter Steeg, P F; Otten, G D; Alderliesten, M; de Weijer, R; Naaktgeboren, G; Bijl, J; Vasbinder, A J; Kershof, I; van Duijvendijk, A M

2001-08-01

407

Sunflower-seed oil body emulsions: Rheology and stability assessment of a natural emulsion  

Microsoft Academic Search

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

D. A. White; I. D. Fisk; J. R. Mitchell; B. Wolf; S. E. Hill; D. A. Gray

2008-01-01

408

Application of Plackett-Burman Design and Box-Behnken Design to Achieve Process Optimization for Geniposide Submicron Emulsion  

Microsoft Academic Search

The objective of this study was to prepare and characterize geniposide submicron emulsion (GP-SME) loaded the geniposide phytosomes (GP-PS) geniposide and optimize the process variables. The physicochemical properties of GP-PS obtained were investigated by means of differential scanning calorimetry. A screening experiment with Plackett-Burman design (PBD) and response surface methodology (RSM) with Box-Behnken design (BBD) was used to optimize the

Peng-Fei Yue; Qin Zheng; Bin Wu; Peng-Yi Hu; Zhen-Feng Wu; Ming Yang

2011-01-01

409

Application of Plackett-Burman Design and Box-Behnken Design to Achieve Process Optimization for Geniposide Submicron Emulsion  

Microsoft Academic Search

The objective of this study was to prepare and characterize geniposide submicron emulsion (GP-SME) loaded the geniposide phytosomes (GP-PS) geniposide and optimize the process variables. The physicochemical properties of GP-PS obtained were investigated by means of differential scanning calorimetry. A screening experiment with Plackett-Burman design and response surface methodology with Box-Behnken design was used to optimize the process parameters of

Peng-Fei Yue; Qin Zheng; Bin Wu; Peng-Yi Hu; Zhen-Feng Wu; Ming Yang

2012-01-01

410

Rheology of high internal phase emulsions.  

PubMed

The mechanical dispersion technology used in this study employs rotor-stator mixers that produce water-continuous high internal phase emulsions (HIPEs) with narrow drop size distributions and small drop sizes, even when the internal phase (oil) viscosity is quite high. Analysis of these HIPEs reveals trends that are consistent with formation by a capillary instability mechanism in which a shear deformation produces highly elongated drops that rupture to form uniform, small droplets. In the search for a predictive tool to aid in the manufacture and use of HIPEs, rheology data for these shear-thinning HIPEs have been compared to data for models in the literature. Existing models do not correctly account for the effect of a high internal phase viscosity on the rheological properties of the HIPE. Another shortcoming is failure to correctly address the shear-thinning exponent. Whereas internal phase viscosity does not seem to affect the shear-thinning exponent, the surfactant apparently plays an important role, possibly through its modification of the interfacial tension and continuous phase rheology. PMID:16460072

Welch, Cynthia F; Rose, Gene D; Malotky, David; Eckersley, Sarah T

2006-02-14

411

Nanoparticle layers controlling drug release from emulsions.  

PubMed

The influence of interfacial layers of silica nanoparticles on the release kinetics of a model lipophilic drug (di-butyl-phthalate (DBP)) from polydimethylsiloxane droplets in water is reported. The nanoparticle layers are formed by self-assembly from solution and their structure is controlled by nanoparticle hydrophobicity and the solution conditions. For DBP loading levels resulting in released concentrations below the solubility limit, release is rapid from uncoated droplets whereas significant sustained release is facilitated by rigid interfacial layers of hydrophobic silica nanoparticles. Activation energies for release are in the range 580-630kJmol(-1), which is ten times greater than for barriers introduced by typical polymeric stabilisers. In contrast, at higher DBP loading levels (total concentration greater than the solubility level), both hydrophilic and hydrophobic nanoparticle layers increase the rate and extent of dissolution compared with uncoated droplets and pure DBP solutions. Nanoparticle layers are shown to significantly influence the release kinetics of lipophilic drugs from oil in water emulsions: either sustained or enhanced release properties can be introduced depending on the nanoparticle layer type and drug loading level. Thus, nanoparticle layers may be engineered to facilitate a range of release behaviours and offer great potential in the delivery of poorly soluble drugs. PMID:17329085

Simovic, Spomenka; Prestidge, Clive A

2007-01-30

412

Investigation of the Demulsification of Water-In-Oil Emulsions Formed When Crude Oil or Fuel Oil is Spilt on the Sea.  

National Technical Information Service (NTIS)

The highly viscous water-in-oil emulsions, formed when crude or fuel oil is spilt at sea, are difficult to collect, and expensive to transport as they contain 50-80% water. Laboratory experiments have been carried out to determine the factors to be consid...

M. A. Lee

1980-01-01

413

A Simple Experiment Illustrating the Structure of Association Colloids.  

ERIC Educational Resources Information Center

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)

Friberg, Stig. E.; Bendiksen, Beverly

1979-01-01

414

Cholesterol improves the utilization of parenteral lipid emulsions.  

PubMed

Lipid emulsions have become an indispensable component of parenteral nutrition. Commercially available emulsions mostly have an identical composition of triglycerides (from plant oils) and egg-yolk phospholipids as emulsifier. Previous attempts to improve the composition of lipid emulsions have focused mainly on the triglyceride moiety. In the first fundamental modification of a lipid emulsion since their broader introduction into clinical medicine, we included free cholesterol in a lipid emulsion. We evaluated elimination and hydrolysis of triglycerides and lipid oxidation (by indirect calorimetry) in 10 healthy male normolipemic volunteers, comparing a conventional lipid emulsion (20% triglycerides) with an otherwise identical emulsion with the addition of 4 g/l free cholesterol. The rise in plasma triglycerides was mitigated during infusion of the cholesterol-enriched solution (323.8 +/- 27.5 vs. 202.0 +/- 18.9 mg.dL-1, p < 0.001), plasma half-life was reduced (41.6 +/- 5.4 vs. 29.3 +/- 5.1 min, p < 0.05), and total-body clearance was enhanced (0.96 +/- 0.1 vs. 1.52 +/- 0.2 ml.b.w.(.)min-1, p < 0.02). The rise in plasma free fatty acids (400.7 +/- 39.0 vs. 532.2 +/- 64.0 mumol.L-1; p < 0.02) and ketone bodies (beta-hydroxybutyrate) (151.6 +/- 37.0 vs. 226.3 +/- 33.01 mumol.L-1; p < 0.02) was augmented. Increases in plasma insulin and glucagon were less pronounced (p < 0.05). The fall in respiratory quotient was greater and the fraction of lipid oxidation as a percentage of total energy expenditure was increased (66.2% +/- 6.0 vs. 70.9% +/- 6.3, p < 0.05) during infusion of the modified solution. No impairment of gas exchange or other side effects were observed. Taken together these results indicate that the elimination of a cholesterol-supplemented lipid emulsion is accelerated, triglyceride hydrolysis is enhanced, and lipid oxidation is augmented. Thus, addition of cholesterol to a lipid emulsion might not only present a means of providing cholesterol in parenteral nutrition but also help to reshape artificial lipid particles to a more chylomicron-resembling composition and improve lipid utilization. PMID:14743580

Druml, Wilfred; Fischer, Margot

2003-11-28

415

The role of lipid emulsion during advanced cardiac life support for local anesthetic toxicity.  

PubMed

Lipid emulsion has recently emerged as a potential antidote for local anesthetic systemic toxicity. This review examines the literature and guidelines for administration of lipid emulsion in the setting of advanced cardiac life support. PMID:21112763

Toledo, P

2010-11-26

416

The role of lipid emulsion during advanced cardiac life support for local anesthetic toxicity  

Microsoft Academic Search

Lipid emulsion has recently emerged as a potential antidote for local anesthetic systemic toxicity. This review examines the literature and guidelines for administration of lipid emulsion in the setting of advanced cardiac life support.

P. Toledo

2011-01-01

417

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

Code of Federal Regulations, 2011 CFR

...Applicability; description of the emulsion crumb rubber subcategory. 428.20 Section 428... EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20...

2011-07-01

418

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

Code of Federal Regulations, 2013 CFR

... false Applicability; description of the asphalt emulsion subcategory. 443.10 Section 443...FOR THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Emulsion Subcategory § 443.10...

2013-07-01

419

Study on Formation of High Performance Ice Slurry by Emulsion in Ice Storage  

NASA Astrophysics Data System (ADS)

This study is focused on an emulsion as a new thermal storage material for ice storage. Two types of emulsions are made of oil-water mixture with a little additive. Oils used are silicone, light and lump oils. Water contents of emulsions are 70,80 and 90 %. The additive is amino group modified silicone oil, and there is no depression of freezing point for the emulsions because of its hydrophobic property. In order to know structures of emulsions, those electric resistances were measured. And components of liquids separating from emulsions were investigated. From above results, it was found that one was W/O type and the other was O/W type. And then, adaptability of two emulsions to the ice storage was discussed, and then, it was found that a high performance ice slurry could be formed by the W/O type emulsion.

Matsumoto, Koji; Oikawa, Ken; Okada, Masashi; Teraoka, Yoshikazu; Kawagoe, Tetsuo

420

Role of liquid crystal in the emulsification of a gel emulsion with high internal phase fraction.  

PubMed

A gel emulsion with high internal oil phase volume fraction was formed via an inversion process induced by a water-oil ratio change. The process involved the formation of intermediate multiple emulsions prior to inversion. The multiple emulsions contain a liquid crystal formed by the surfactant with water; this was both predicted by the equilibrium phase diagram as well as observed using polarization microscopy. These multiple emulsions were more stable compared to alternative multiple emulsions prepared in the same way with a surfactant that does not form liquid crystals. While the formation of a stable intermediate multiple emulsion may not be a necessary condition for the inversion to occur, the transitional presence of a liquid crystal proved to be a significant factor in the stabilization of the intermediate multiple emulsions. The resulting gel emulsion contained a small fraction of the liquid crystal according to the phase diagram, and it exhibited excellent stability. PMID:19781712

Liu, Yihan; Friberg, Stig E

2009-09-03

421

Emulsions of perfluorinated solvents for intravascular gas transport.  

PubMed

During the past several years we have progressed from the use of perfluorinated substances, which were good gas solvents but often produced unexpected physiological reactions, to a point where emulsions of pure perfluorinated substances can be made in a reproducible way. A standardized method of making emulsions has now been developed. The physical properties of the perfluorinated substances needed to make useful emulsions have been defined. Specifically, perfluorinated substances having vapor pressures above about 40 torr must be avoided as they produce pulmonary gas embolism; also lower boiling components having vapor pressures above about 40 torr must be excluded. The relationship between chemical structure and several physiological and pharmacological effects has been delineated. Perfluorinated substances containing only carbon and fluorine, or those containing carbon, fluorine, and either bromine or iodine have reasonably short dwell times in the liver. Perfluorinated iodo- and bromo-compounds dissolve oxygen and are radiopaque. Present iodo-perfluorinates are unstable in the presence of light. Perfluorodecalin can enter and leave the liver without changing the liver's ultrastructure. Both egg phospholipid and Pluronic F68 are useful in making perfluorodecalin emulsions. Perfluorodimethyladamantane makes a fine-particle stable emulsion. There is a bright future for perfluorinated substances in a number of areas of research in biology and medicine. PMID:1126444

Clark, L C; Wesseler, E P; Kaplan, S; Miller, M L; Becker, C; Emory, C; Stanley, L; Becattini, F; Obrock, V

1975-05-01

422

Stability determination of crude oil emulsions by electrorheological measurement  

NASA Astrophysics Data System (ADS)

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.

Alvarado, Vladimir; Wang, Xiuyu; Plancher, Henry

2008-11-01

423

Investigation of different emulsion systems for dermal delivery of nicotinamide.  

PubMed

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

Tuncay, Sakine; Ozer, Ozgen

2013-06-06

424

Delivery of Chlorambucil Using an Acoustically-Triggered, Perfluoropentane Emulsion  

PubMed Central

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.

Fabiilli, Mario L.; Haworth, Kevin J.; Sebastian, Ian E.; Kripfgans, Oliver D.; Carson, Paul L.; Fowlkes, J. Brian

2010-01-01

425

Treatment methods for breaking certain oil and water emulsions  

DOEpatents

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.

Sealock, Jr., L. John (W. Richland, WA); Baker, Eddie G. (Richland, WA); Elliott, Douglas C. (Richland, WA)

1992-01-01

426

Freeze-thaw stability of water-in-oil emulsions.  

PubMed

Factors influencing water-in-oil emulsion stability during freeze/thaw-cycling, namely interfacial crystallization vs. network crystallization and the sequence of crystallization events (i.e., dispersed vs. continuous phase or vice versa), are assessed. We show that destabilization is most apparent with a liquid-state emulsifier and a continuous oil phase that solidifies prior to the dispersed phase. Emulsions stable to F/T-cycling are obtained when the emulsifier crystallizes at the oil-water interface or in emulsions where the continuous phase crystallizes after the dispersed aqueous phase. The materials used are two food-grade oil-soluble emulsifiers - polyglycerol polyricinoleate (PGPR) and glycerol monostearin (GMS) and two continuous oil phases with differing crystallization temperatures - canola oil and coconut oil. Emulsion stability is assessed with pulsed field gradient NMR droplet size analysis, sedimentation, microscopy and differential scanning calorimetry. This study demonstrates the sequence of crystallization events and the physical state of the surfactant at the oil-water interface strongly impact the freeze-thaw stability of water-in-oil emulsions. PMID:19683718

Ghosh, S; Rousseau, D

2009-07-25

427

Injectable Lipid Emulsions--Advancements, Opportunities and Challenges  

PubMed Central

Injectable lipid emulsions, for decades, have been clinically used as an energy source for hospitalized patients by providing essential fatty acids and vitamins. Recent interest in utilizing lipid emulsions for delivering lipid soluble therapeutic agents, intravenously, has been continuously growing due to the biocompatible nature of the lipid-based delivery systems. Advancements in the area of novel lipids (olive oil and fish oil) have opened a new area for future clinical application of lipid-based injectable delivery systems that may provide a better safety profile over traditionally used long- and medium-chain triglycerides to critically ill patients. Formulation components and process parameters play critical role in the success of lipid injectable emulsions as drug delivery vehicles and hence need to be well integrated in the formulation development strategies. Physico-chemical properties of active therapeutic agents significantly impact pharmacokinetics and tissue disposition following intravenous administration of drug-containing lipid emulsion and hence need special attention while selecting such delivery vehicles. In summary, this review provides a broad overview of recent advancements in the field of novel lipids, opportunities for intravenous drug delivery, and challenges associated with injectable lipid emulsions.

Hippalgaonkar, Ketan; Majumdar, Soumyajit

2010-01-01

428

Microfluidic emulsion separation---simultaneous separation and sensing by multilayer nanofilm structures  

Microsoft Academic Search

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

P. Uhlmann; F. Varnik; P. Truman; G. Zikos; J.-F. Moulin; P. Müller-Buschbaum; M. Stamm

2011-01-01

429

Effect of sugar on the rheological properties of sunflower oil–water emulsions  

Microsoft Academic Search

The rheological properties of sunflower oil–water emulsions were studied at constant oil (79%), with varying sugar concentrations (0.0–8.0%) and different temperatures (25–65°C). Sugar improved the emulsion stability. The empirical power law fitted the apparent viscosity-rotational speed data. All emulsions exhibited pseudoplastic behaviour. An average flow behaviour index of 0.49±0.03 was proposed as power law index for all emulsions. The consistency

Medeni Maskan; Fahrettin Gö?ü?

2000-01-01

430

The structure and properties of core-shell type acrylic-polyurethane hybrid aqueous emulsions  

Microsoft Academic Search

Three types of core-shell type acrylic-polyurethane hybrid aqueous emulsions were prepared by soapfree emulsion polymerization techniques. The formation of core-shell morphology was clearly observed by transmission electron microscopy in the case of A\\/U-type emulsions whose core and shell regions are occupied by acrylic polymer and polyurethane, respectively. The size and the distribution of emulsion particles are found to vary drastically

M. Hirose; F. Kadowaki; Jianhui Zhou

1997-01-01

431

Binding of Rhizomucor miehei lipase to emulsion interfaces and its interference with surfactants  

Microsoft Academic Search

Interactions between Rhizomucor miehei lipase and emulsion droplets were studied in oil-in-water emulsions. The emulsions were stabilized by either the cationic surfactant didodecyldimethylammonium bromide, the anionic surfactant sodium bis(2-ethylhexyl)sulfosuccinate or the non-ionic surfactant 1-(2-ethylhexyl)-3-(2-ethylbutyl)-2-hexaethylene glycerol ether. By measuring the mobility of the emulsion droplets it was shown that the lipase bound to droplets stabilized by the cationic surfactant, but not

Peter Skagerlind; Mikael Jansson; Björn Bergenståhl; Karl Hult

1995-01-01

432

Ultra-fine-grain silver halide emulsions for color holography: preparation and spectral characterization  

Microsoft Academic Search

Ultra-fine-grain silver halide emulsions for true color reflection holograms were prepared in our laboratory. The emulsions with average grain diameters of about 10 nm were spectrally sensitized with various types of cyanine dyes. The absorption spectra of dyed emulsion sols could be observed directly because the sols showed no observable scattering. The photographic and holographic characteristics of our laboratory-made emulsion

Masashi Iwasaki; Toshihiro Kubota

1998-01-01

433

Emulsion droplet spreading at air\\/water interfaces: mechanisms and relevance to the whipping of cream  

Microsoft Academic Search

Keywords:<\\/span><\\/strong>emulsion, spreading coefficient, surface tension, emulsifier, whipped cream, dairy foam, partial coalescence <\\/o:p><\\/strong><\\/span>In this thesis, the interaction between emulsion droplets and expanding air\\/water interfaces was investigated. The objective was to deepen our knowledge concerning the physical processes that take place at the expanding air surfaces that form during aeration of emulsions. Emulsions can become aerated as a result of

N. E. Hotrum

2004-01-01

434

Preparation and stabilization of simple and multiple emulsions using a microporous glass membrane  

Microsoft Academic Search

A microporous glass membrane with a narrow range of pore sizes was used for the preparation of simple and water-oil-water (W\\/O\\/W) type emulsions using egg yolk phospholipids and soybean oil. Simple oil-in-water (O\\/W) and water-in-oil (W\\/O) emulsions and a W\\/O\\/W type emulsion were successfully prepared using the membranes without any coalescence of oil drops or breakdown of the emulsions. The

Yoshinori Mine; Masaaki Shimizu; Tadao Nakashima

1996-01-01

435

Breakup of bubbles and drops in steadily sheared foams and concentrated emulsions.  

PubMed

This experimental study is focused on the process of bubble breakup in steadily sheared foams, at constant shear rate or constant shear stress. Two different types of surfactants were used and glycerol was added to the aqueous phase, to check how the bubble breakup depends on the surface modulus and on bulk viscosity of the foaming solutions. The experiments show that bubble breakup in foams occurs above a well defined critical dimensionless stress, tau[over]CR identical with(tauCRR/sigma) approximately 0.40, which is independent of surfactant used, solution viscosity, and bubble volume fraction (varied between 92 and 98%). Here tauCR is the dimensional shear stress, above which a bubble with radius R and surface tension sigma would break in sheared foam. The value of the critical stress experimentally found by us tau[over]CR approximately 0.40, is about two orders of magnitude lower than the critical stress for breakup of single bubbles in sheared Newtonian liquids, tau[over]CR approximately 25. This large difference in the critical stress is explained by the strong interaction between neighboring bubbles in densely populated foams, which facilitates bubble subdivision into smaller bubbles. A strong effect of bubble polydispersity on the kinetics of bubble breakup (at similar mean bubble size) was observed and explained. Experiments were also performed with hexadecane-in-water emulsions of drop volume fraction 83%emulsions. Qualitatively similar behavior was observed to that of foams, with the critical dimensionless stress for drop breakup being lower, tau[over]CR approximately 0.15, and practically independent of the drop volume fraction and viscosity ratio (varied between 0.01 and 1). This critical stress is by several times lower than the critical stress for breakage of single drops in sheared Newtonian fluids at comparable viscosity ratio, which evidences for facilitated drop subdivision in concentrated emulsions. To explain the measured low values of the critical stress, a different type of capillary instability of the breaking bubbles and drops in concentrated foams and emulsions is proposed and discussed. PMID:19113128

Golemanov, K; Tcholakova, S; Denkov, N D; Ananthapadmanabhan, K P; Lips, A

2008-11-24

436

The FASES instrument development and experiment preparation for the ISS  

NASA Astrophysics Data System (ADS)

The FASES experiments target the investigation of the stability of emulsions. The main objec-tives are the study of the surfactant adsorption at the liquid / liquid interfaces, the interaction of the droplets as well as the behaviour of the liquid film between nearby drops. Particular focus is given to the dynamic droplet evolution during emulsion destabilisation. The results of the experiments shall support development of methods for the modelling of droplet size distri-butions, which are important to many industries using stable emulsions like food production, cosmetics and pharmaceutics or unstable emulsions as required for applications in waste water treatment or crude oil recovery. The development of the experimental instrumentation was initiated in 2002. The flight instru-ment hardware development was started in 2004 and finally the flight unit was completed in 2009. Currently the final flight preparation is proceeding targeting a launch to the International Space Station (ISS) with Progress 39P in September 2010. The experiment setup of the instrument is accommodated in a box type insert called Experiment Container (EC), which will be installed in the Fluid Science Laboratory part of the European Columbus module of the ISS. The EC is composed of two diagnostics instruments for the investigation of transparent and opaque liquid emulsion. The transparent emulsions will be subject to the experiment called "Investigations on drop/drop interactions in Transparent Emulsions" (ITEM). The opaque emulsion samples will be studied in the experiment called "Investigations on concentrated or opaque Emulsions and on Phase Inversions" (EMPI). The thermal conditioning unit (TCU) allows performing homogeneous thermalization, tem-perature sweeps, emulsion preparation by stirrer, and optical diagnostics with a scanning mi-croscope. The objective of the instrument is the 3D reconstruction of the emulsion droplet distribution in the liquid matrix in terms of the droplet sizes, location and their time depen-dent evolution. The TCU will be used for the stability experiment ITEM-S and the droplet freezing experiment ITEM-F. The Differential Scanning Calorimeter (DSC) will give an information about the evolution of the emulsion through the droplet size distribution and the dispersion state of the droplets within the emulsion during a controlled temperature sweep by measuring the latent heat of droplet freezing and melting during the EMPI experiments. For this purpose the calorimeter is equipped with a reference sample filled with a pure liquid matrix and a similar measurement sample filled with the specific emulsion under investigation. The differential heat flux between measurement sample and reference sample is measured with a sensitive heat flux sensor. Each instrument is serviced by a robotic sample stowage system, which accommodates in total 44 different ITEM and EMPI emulsion samples each filled with a specific composition of the emulsion. Currently the flight preparation is ongoing with particular focus on the preparation of the emulsion flight sample set and the instrument's operating parameters. The FASES flight instrument was developed by ASTRIUM Space Transportation Germany with support of RUAG Aerospace Wallisellen under ESA / ESTEC contract. The science team of FASES is supported by ESA/ESTEC (Microgravity Application Programme, AO99-052).

Picker, Gerold; Gollinger, Klaus; Greger, Ralf; Dettmann, Jan; Winter, Josef; Dewandre, Thierry; Castiglione, Luigi; Vincent-Bonnieu, Sebastien; Liggieri, Libero; Clausse, Daniele; Antoni, Mickael

437

Role of nanoadditive blended biodiesel emulsion fuel on the working characteristics of a diesel engine  

Microsoft Academic Search

Biodiesel emulsions are considered as the propitious alternative fuels for diesel engines. The need of biodiesel emulsion fuels for the diesel engines is to curtail the dependency on the fossil fuels in context to the world energy oil crisis. Henceforth, the present study provides a tangible pathway to prepare and to ameliorate the biodiesel emulsion fuel on incorporating potential alumina

J. Sadhik Basha; R. B. Anand

2011-01-01

438

Measurement of charge of heavy ions in emulsion using a CCD camera  

Microsoft Academic Search

A system has been developed for semi-automated determination of the charges of heavy ions recorded in nuclear emulsions. The profiles of various heavy ion tracks in emulsion, both accelerator beam ions and fragments of heavy projectiles, were obtained with a CCD camera mounted on a microscope. The dependence of track profiles on illumination, emulsion grain size and density, background in

D. Kudzia; M. L. Cherry; P. Deines-Jones; R. Holynski; A. Olszewski; B. S. Nilsen; K. Sengupta; M. Szarska; A. Trzupek; C. J. Waddington; J. P. Wefel; B. Wilczynska; H. Wilczynski; W. Wolter; B. Wosiek; K. Wozniak

1999-01-01

439

The Stabilization of Water-in-Hydrocarbon Emulsions by Asphaltenes and Resins  

Microsoft Academic Search

The role of asphaltenes and resins in stabilizing water-in-crude oil emulsions was investigated by measuring the interfacial composition and stability of model emulsions composed of water with mixtures of toluene, heptane, asphaltenes, resins, and native solids. The interfacial composition (mass surface coverage) was determined from a combination of emulsion surface area measurements and concentration measurements of both the continuous and

Olga V. Gafonova; Harvey W. Yarranton

2001-01-01

440

RECOVERY OF NICKEL VIA LIQUID EMULSION MEMBRANE PROCESS USING METHANE SULFONIC ACID AS A STRIPPANT  

Microsoft Academic Search

A liquid emulsion membrane (LEM) process is considered for the enrichment of nickel ions from dilute aqueous solutions. The liquid emulsion membrane consisted of a carrier di-2 ethylhexyl phosphoric acid (D2EHPA), an organic diluent, an emulsifying agent, and an aqueous stripping agent thereby having water in oil emulsion. Various stripping agents (hydrochloric, sulfuric, nitric, and methane sulfonic acid) were tested

P. S. Kulkarni; K. K. Tiwari; V. V. Mahajani

2001-01-01

441

Timing the deposition of an asphalt plugging material from an asphalt-cationic emulsion  

Microsoft Academic Search

A mixture of urea and urease provides a timed breaking of a cationic asphalt emulsion when the emulsion is used in plugging a subsurface formation. The composition is especially useful in plugging low temperature formations. The composition is a pH-increasing reactant, the higher pH breaking the emulsion. (11 claims)

Cavin

1977-01-01

442

Influence of thickness in the holographic emulsion composed by rosin and BPB dye  

NASA Astrophysics Data System (ADS)

We analyze diffraction gratings behavior recorded on a phase holographic emulsion. This emulsion is composed with resin and bromophenol blue dye (BPB) they have a diffraction efficiency (?) from 0.22 to 0.615% order, and their thickness are different in the holographic emulsion.

Ibarra, Juan C.; Ortiz-Gutierrez, Mauricio; Olivares-Perez, Arturo; Perez-Cortes, Mario

2004-10-01

443

Rheological studies to objectify sensations occurring when cosmetic emulsions are applied to the skin  

Microsoft Academic Search

When cosmetic emulsions are applied to the skin, different flow conditions arise because the film thickness of the emulsion decreases as it is rubbed in. The sensations experienced during application — the so-called skin feeling — therefore result in part from the flow properties of an emulsion subjected to varying conditions of stress. To take this into account when investigating

R Brummer; S Godersky

1999-01-01

444

Impact of Weighting Agents and Sucrose on Gravitational Separation of Beverage Emulsions  

Microsoft Academic Search

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

Ratjika Chanamai; D. Julian McClements

2000-01-01

445

Demulsification of Asphaltene-Stabilized Emulsions—Correlations of Demulsifier Performance with Crude Oil Composition  

Microsoft Academic Search

Model asphaltene-stabilized emulsions are used to study the impact of oil composition on the efficiency of demulsification. Varying ratios of toluene and heptane, mixed with asphaltene extracted from a Gulf of Mexico crude oil, were mixed with water to produce emulsions that exhibited characteristic coalescence (water drop) rates. Commercial demulsifiers of varying types and chemistries were added to these emulsions,

Patrick J. Breen; Andrew Yen; Joshua Tapp

2003-01-01

446

Double emulsions stabilized with hybrids of natural polymers for entrapment and slow release of active matters  

Microsoft Academic Search

The main focus and efforts for the next few years in the area of emulsion technology will be to improve stability and control the release of active matter in double emulsions (3rd World Congress on Emulsions, Lyon, France, September 2002). Almost any possible blends of low-molecular weight emulsifiers, oils, cosolvents and coemulsifiers have been already tested. Biopolymers, synthetic graft and

A. Benichou; A. Aserin; N. Garti

2004-01-01

447

Critical Review of Techniques and Methodologies for Characterization of Emulsion Stability  

Microsoft Academic Search

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

David Julian Mcclements

2007-01-01

448

A stable, radioactive substrate emulsion for assay of I i poprotein I ipase  

Microsoft Academic Search

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

Peter Nilsson-Ehle; Michael C. Schotz

449

ZnO nanoparticle-containing emulsions for transparent, hydrophobic UV-absorbent films  

Microsoft Academic Search

A simple method for the preparation of thin, zinc oxide nanoparticle-containing films showing high UV absorption, high transmittance in the visible range (>88%), and water repellence with contact angles of 120° is presented. The films are coated from an emulsion containing the hydrophobic polymer and the nanoparticles. This emulsion was prepared by mixing commercial o\\/w emulsions used for hydrophobic coatings

Britta Tigges; Martin Möller; Oliver Weichold

2010-01-01

450

Mobility control through spontaneous formation of nanoparticle stabilized emulsions  

NASA Astrophysics Data System (ADS)

We report on measurements of the flow pattern and in-situ saturations when n-octane displaces a brine in which surface treated silica nanoparticles are dispersed. The nanoparticles are known to stabilize octane-in-water emulsions. We find that the displacement front is more spatially uniform, and with a later breakthrough when compared to a control displacement with no in-situ nanoparticles. Pressure measurements during the displacement are consistent with generation of a viscous phase such as an emulsion. These observations suggest that a nanoparticle stabilized emulsion is formed during the displacement which acts to suppress the viscous instability. We argue that generation of droplets of nonwetting phase occurs at the leading edge of all drainage displacements. The droplets rejoin the bulk phase in the absence of stabilizing agents, but are preserved when nanoparticles adhere to the fluid/fluid interface.

DiCarlo, D. A.; Aminzadeh, B.; Roberts, M.; Chung, D. H.; Bryant, S. L.; Huh, C.

2011-12-01

451

Degradation of kinetically-stable o/w emulsions.  

PubMed

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

Capek, Ignác

2004-03-19

452

Binding of local anaesthetics to the lipid emulsion Clinoleic™ 20%.  

PubMed

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

Evans, J A; Wallis, S C; Dulhunty, J M; Pang, G

2013-09-01

453

Demulsification of a crude oil middle phase emulsion  

SciTech Connect

The middle phase emulsion of a crude oil emulsion produced by a surfactant flooding of an oil reservoir is demulsified by contacting it with a water-soluble alkali metal hydroxide in an amount and under conditions sufficient to cause the hydrolysis of the middle phase emulsion and its subsequent separation into phases, wherein one of the phases is primarily an oil phase. The oil phase is then separated and, thereafter, can be further demulsified by demetalizing the oil by contacting it with a carboxylic acid or an amine salt of a carboxylic acid. It may be desirable to concurrently or subsequently treat the oil with an organic base, which can also be an amine demulsifier, to obtain a pH of from about 7 to about 9 in the final oil phase recovered from the acid demetalization step.

Duke, R.B.

1984-03-27

455

a Search for Quark-Gluon Plasma Formation in High Energy Heavy Ion Interactions in Nuclear Emulsion Detectors.  

NASA Astrophysics Data System (ADS)

High energy heavy ion interactions observed in the JACEE balloon-borne cosmic ray emulsion chambers, the Fermilab E171 and E237, and CERN EMU-1 accelerator emulsion chamber detectors are compared with results from other accelerator experiments and examined for evidence of quark gluon plasma formation. No significant increase in the produced photon transverse momentum is found for events of high entropy density. It is demonstrated that the hadronic emission region size can be determined by Bose Einstein correlations from produced particle angles without knowledge of individual particle momenta. The hadronic emission region size for nuclear interactions by proton, oxygen, and sulfur projectiles is found to be 1.5 +/- 0.3, 3.5 +/- 0.5, 4.1 +/- 0.4 fm, not significantly different from the nuclear radius as determined by scattering measurements.

Strausz, Steven Chester

456

Histological localization of methylmercury in mouse brain and kidney by emulsion autoradiography of /sup 203/Hg  

SciTech Connect

Some investigators have abandoned the use of /sup 203/Hg emulsion autoradiography in favor of chemical methods of microscopic localization of mercury. However, recent studies indicate that the latter methods identify only inorganic mercury, or some product of inorganic mercury, making them of little or no value for studies of methylmercury toxicity. Doubts about the use of /sup 203/Hg for microscopic localization arose because of the high maximum energy of its emissions and the concern that its latent images might be confounded with silver grains produced by chemical reactions between tissue Hg and the silver supplied by photographic emulsions. Examination of the spectrum of emissions from /sup 203/Hg demonstrates that its maximum energy emissions are rare. The mean energy of /sup 203/Hg emissions is in the 50-ke V range and the modal emissions are close to 0 ke V, indicating sufficient low energy emissions for autoradiography. In preliminary experiments, methylmercury content of mouse brain was shown to be stable through the steps of tissue processing for plastic sections. A direct comparison of autoradiographic grain counts from tissue treated with cold or hot methylmercury demonstrated that no grains above background were produced in the absence of nuclear emissions--only hot samples affected emulsion. In the kidneys of mice killed 24 hr after dosing, grains were most numerous over cortical tubules and significantly less numerous over glomeruli. In the cerebellum, the molecular layer was significantly more heavily labeled than the granular layer. The number of grains was greatly increased in every region by increasing the specific activity of the methylmercury dosing solution while holding the dose of methylmercury constant.

Rodier, P.M.; Kates, B.

1988-02-01

457

TURBISCAN MA 2000: multiple light scattering measurement for concentrated emulsion and suspension instability analysis.  

PubMed

Emulsion or suspension destabilisation often results from coalescence or particle aggregation (flocculation) leading to particle migration (creaming or sedimentation). Creaming and sedimentation are often considered as reversible, while coalescence and flocculation spell disaster for the formulator. Thus, it is of prime importance to detect coalescence or cluster formation at an early stage to shorten the ageing tests and to improve the formulations. This work mainly concerns the independent and anisotropic scattering of light from an emulsion or suspension in a cylindrical glass measurement cell, in relation with the optical analyser TURBISCAN MA 2000. The propagation of light through a concentrated dispersion can be used to characterise the system physico-chemical stability. Indeed, photons undergo many scattering events in an optically thick dispersion before escaping the medium and entering a receiver aperture. Multiple scattering thus contributes significantly to the transmitted and backscattered flux measured by TURBISCAN MA 2000. We present statistical models and numerical simulations for the radiative transfer in a suspension (plane or cylindrical measurement cells) only involving the photon mean path length, the asymmetry factor and the geometry of the light receivers. We further have developed an imaging method with high grey level resolution for the visualisation and the analysis of the surface flux in the backscattered spot light. We compare the results from physical models and numerical simulations with the experiments performed with the imaging method and the optical analyser TURBISCAN MA 2000 for latex beads suspensions (variable size and particle volume fraction). We then present a few examples of concentrated emulsion and suspension instability analysis with TURBISCAN 2000. It is shown that the instrument is able to characterise particle or aggregate size variation and particle/aggregate migration and to detect these phenomena much more earlier than the operator's naked eye, especially for concentrated and optically thick media. PMID:18967735

Mengual, O; Meunier, G; Cayré, I; Puech, K; Snabre, P

1999-09-13

458

Method of extracting and reutilizing surfactants from emulsions  

SciTech Connect

This is a claim for extracting surfactants from produced emulsions of oil, water and surfactant and concentrating the surfactants into a relatively small volume, emulsion phase that can be reutilized in surfactant flooding. The two phases left behind in the extraction are a substantially water-free and surfactant-free crude oil phase and an oil-free aqueous phase. The extracting compounds employed are the alkali metal salts and ammonium salts of cumene sulfonate, propyl benzene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate.

Maddox, J. Jr.

1985-04-30

459

Pure protein scaffolds from pickering high internal phase emulsion template.  

PubMed

The formation of hierarchical porous protein scaffolds from oil-in-water (o/w) high internal phase emulsions (HIPEs) stabilized by bovine serum albumin (BSA) protein nanoparticles (Pickering HIPE) is reported. The route consists of three principal steps. First, a stable o/w HIPE stabilized by BSA protein nanoparticles is formulated. Next, crosslinking the dispersed protein nanoparticles gives rise to a gel in the continuous water phase to freeze the emulsion's microstructure. Finally, removal of the oil components and water directly leads to a three dimensional, bimodal meso-macroporous protein scaffold, which is suitable for a wide range of biomedical applications. PMID:23060090

Li, Zifu; Xiao, Manda; Wang, Jianfang; Ngai, To

2012-10-12

460

Invert emulsion as a medium for fungal lipase activity  

Microsoft Academic Search

An extracellular lipase from the fungusPythium ultimum was active in an invert [water-in-oil] emulsion consisting of 4% water emulsified into edible oils with taurocholic acid\\u000a as the surfactant. The pH range for optimum lipolytic activity was 7.5–8.5, and the optimum temperature for activity was 45C.\\u000a Specific activity of the purified lipase was 919.5 mol\\/min\\/mg protein in the invert emulsion. Water

Zahid Mozaffar; John D. Weete

1995-01-01

461

Restricted diffusion: An effective tool to investigate food emulsions  

Microsoft Academic Search

We present a method to extract from pulsed-field-gradient spin-echo NMR measurements, the droplet size distributions in emulsions\\u000a and the self-diffusion coefficient of the dispersed phase. The method is applied to butter and water\\/extra-virgin olive oil\\u000a emulsions. The droplet size distributions are in agreement with optical microscopy analysis. The butter size distribution\\u000a is a log—normal form and the effect of the

G. Colafemmina; G. Palazzo; A. Ceglie; L. Ambrosone; G. Cinelli; V. Di Lorenzo

462

Surface electric properties of emulsions of apolar reagents  

SciTech Connect

This article presents the results of studies of surface electric properties of kerosene and AAR-2 (apolar aromatized reagent) emulsons in water, which can be used in coal slime flotation, in presence of various salts and high-molecular flocculants. The data obtained were compared with the effect of electrolytes on the surface electric properties of a model emulsion of heptane in water stabilized by sodium hapthenate. The studies indicate that similarity of changes in the electrokinetic properties of various emulsions in presence of electrolytes and flocculants.

Baichenko, A.A.; Baran, A.A.

1986-09-01

463

Microscopic structure of water in a water/oil emulsion  

NASA Astrophysics Data System (ADS)

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.

Mancinelli, R.; Bruni, F.; Ricci, M. A.; Imberti, S.

2013-05-01

464

Balloon-borne gamma-ray telescope with nuclear emulsion  

Microsoft Academic Search

We are planning to observe cosmic gamma-ray in the energy range 10MeV to 100GeV by balloon-borne gamma-ray telescope with nuclear emulsion. Nuclear emulsion is a precise tracker. By detecting starting point of electron pair, gamma-ray direction can be determined precisely (1.4mrad@1-2GeV). This is much better than Fermi Gamma-ray Space Telescope launched June 2008. Now we are developing the gamma-ray telescope

Satoru Takahashi; Shigeki Aoki; Tsutomu Fukuda; Kaname Hamada; Toshio Hara; Atsushi Iyono; Jiro Kawada; Masashi Kazuyama; Koichi Kodama; Masahiro Komatsu; Shinichiro Koshiba; Hirotaka Kubota; Seigo Miyamoto; Motoaki Miyanishi; Kunihiro Mor-Ishima; Naotaka Naganawa; Tatsuhiro Naka; Mitsuhiro Nakamura; Toshiyuki Nakano; Kimio Niwa; Yoshiaki Nonoyama; Keita Ozaki; Hiroki Rokujo; Takashi Sako; Os-Amu Sato; Yoshihiro Sato; Kazuya Suzuki; Atsumu Suzuki; Ikuo Tezuka; Junya Yoshida; Teppei Yoshioka

2010-01-01

465

Double Emulsions through Wettability Control in PDMS Microfluidic Devices  

NASA Astrophysics Data System (ADS)

Hydrodynamic Flow Focusing allows for the well-controlled production of monodisperse double and multiple emulsions. While this method of emulsification is well described for glass capillary devices, it has not yet been developed for PDMS devices that are readily accessible using soft-lithography. The reason is the difficulty of spatially controlling the wetting behavior of PDMS microchannels. We will present a novel technique of photopatterning that allows for the production of double emulsions in PDMS devices. Moreover, owing to an optimized setup, smaller droplets may be made down to a size range that was not accessible using the conventional approaches.

Holtze, Christian; Mele, Elisa; Weitz, David

2007-03-01

466

Linear viscoelasticity of emulsions. Part 1. The effect of an interfacial film on the dynamic viscosity of nondilute emulsions  

SciTech Connect

The dynamic viscosity of nondilute monodisperse emulsions is calculated by using a cell model. Two possibilities for describing the mechanical properties of the interfacial film between the internal and the external phase are considered: (a) the film is assigned a two-dimensional linear viscoelastic behavior and (b) the film is treated as a shell with finite thickness containing a Newtonian liquid. The resulting expressions for the dynamic viscosity show that model b has two relaxation times and model a has at least two or more. If a Voigt-Kelvin model is used to describe the interfacial rheology, model a will also have just two relaxation times. The results obtained may be used to interpret measurements on emulsions in terms of microscopic parameters of these emulsions. 23 references.

Oosterbroek, M.; Mellema, J.

1981-11-01

467

Encapsulation of Resveratrol Using Water-in-Oil-in-Water Double Emulsions  

Microsoft Academic Search

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

Yacine Hemar; Li Jiang Cheng; Christine M. Oliver; Luz Sanguansri; Maryann Augustin

2010-01-01

468

Constant infusion rates of lipid emulsions to stabilize plasma triglyceride concentrations: Medium-chain triglyceride\\/long-chain triglyceride emulsions (MCT\\/LCT) versus LCT  

Microsoft Academic Search

As medium-chain triglyceride emulsions (MCT) are more rapidly hydrolyzed than long-chain triglyceride emulsions (LCT), MCT\\/LCT\\u000a tends to be infused faster than LCT. The purpose of the present study was to determine the most appropriate infusion rate\\u000a for MCT\\/LCT to stabilize plasma concentrations of triglyceride (TG), being equivalent to the optimal infusion rate of the\\u000a emulsion. A TG clamp was set

Keiji Iriyama; Chikao Miki; Takahito Inoue; Nobuaki Kawarabayashi; Hisashi Urata; Chika Shigemori

1998-01-01

469

Enhanced stabilization of cloudy emulsions with gum Arabic and whey protein isolate.  

PubMed

Cloudy emulsions are oil-in-water (O/W) emulsions normally prepared as concentrates, further diluted, per request, into the final beverage. The cloudy emulsion provides flavor, color, and cloud (turbidity) to the soft drink. These systems are stabilized by emulsifiers and/or amphiphilic polysaccharides. Cloudy emulsions based on naturally occurring food grade emulsifiers were studied in the present work. Two charged natural biopolymers, whey protein isolate (WPI) and gum Arabic (GA), are interacted in aqueous solution to form charge-charge interactions improving the emulsion stability. The emulsions were high sheared (Microfluidizer) and characterized by particle size distribution analysis (DLS), optical centrifugation (LUMiFuge), optical microscopy observations, and turbidity measurements. Emulsions obtained from 10wt% of 3:1wt. ratio WPI:GA, at pH 7 (10wt% canola oil) show better stability than emulsions stabilized by GA or WPI alone. The droplet sizes were smaller than 1microm and did not grow significantly during 1 month of incubation at 25 degrees C. The D-limonene-based emulsion droplets were larger (> 2microm) than those made with vegetable oils immediately after preparation and underwent significant droplet size increase (coalescence) within 1 month (>8 microm). The emulsion with turbidity suitable as a cloudy emulsion was composed of 3wt% WPI:GA (3:1) and 20wt% canola oil. PMID:20149604

Klein, Miri; Aserin, Abraham; Svitov, Inna; Garti, Nissim

2010-01-21

470

Immunomodulatory and Physical Effects of Oil Composition in Vaccine Adjuvant Emulsions  

PubMed Central

Squalene-based oil-in-water emulsions have been used for years in some seasonal and pandemic influenza vaccines. However, concerns have been expressed regarding squalene source and potential biological activities. Little information is available regarding the immunomodulatory activity of squalene in comparison with other metabolizable oils in the context of oil-in-water emulsions formulated with vaccines. The present work describes the manufacture and physical characterization of emulsions composed of different classes of oils, including squalene, long chain triglycerides, a medium chain triglyceride, and a perfluorocarbon, all emulsified with egg phosphatidylcholine. Some differences were apparent among the non-squalene oils in terms of emulsion stability, including higher size polydispersity in the perfluorocarbon emulsion, more rapid visual instability at 60 °C for the long-chain triglyceride and perfluorocarbon emulsions, and an increased creaming rate in the medium-chain triglyceride emulsion at 60 °C as detected by laser scattering optical profiling. The biological activity of each of these emulsions was compared when formulated with either a recombinant malaria antigen or a split-virus inactivated influenza vaccine. Overall, vaccines containing the squalene emulsion elicited higher antibody titers and more abundant long-lived plasma cells than vaccines containing emulsions based on other oils. Since squalene-based emulsions show higher adjuvant potency compared to the other oils tested, non-squalene oils may be more suitable as carriers of amphiphilic or hydrophobic immunostimulatory molecules (such as TLR agonists) rather than as stand-alone adjuvants.

Fox, Christopher B.; Baldwin, Susan L.; Duthie, Malcolm S.; Reed, Steven G.; Vedvick, Thomas S.

2011-01-01

471

Influence of droplet charge on the chemical stability of citral in oil-in-water emulsions.  

PubMed

The chemical stability of citral, a flavor component widely used in beverage, food, and fragrance products, in oil-in-water emulsions stabilized by surfactants with different charge characteristics was investigated. Emulsions were prepared using cationic (lauryl alginate, LAE), non-ionic (polyoxyethylene (23) lauryl ether, Brij 35), and anionic (sodium dodecyl sulfate, SDS) surfactants at pH 3.5. The citral concentration decreased over time in all the emulsions, but the rate of decrease depended on surfactant type. After 7 d storage, the citral concentrations remaining in the emulsions were around 60% for LAE- or Brij 35-stabilized emulsions and 10% for SDS-stabilized emulsions. An increase in the local proton (H(+)) concentration around negatively charged droplet surfaces may account for the more rapid citral degradation observed in SDS-stabilized emulsions. A strong metal ion chelator (EDTA), which has previously been shown to be effective at increasing the oxidative stability of labile components, had no effect on citral stability in LAE- or Brij 35-stabilized emulsions, but it slightly decreased the initial rate of citral degradation in SDS-stabilized emulsions. These results suggest the surfactant type used to prepare emulsions should be controlled to improve the chemical stability of citral in emulsion systems. PMID:20722908

Choi, Seung Jun; Decker, Eric Andrew; Henson, Lulu; Popplewell, L Michael; McClements, David Julian

2010-08-01

472

Non-coalescence of oppositely charged droplets in pH-sensitive emulsions  

PubMed Central

Like charges stabilize emulsions, whereas opposite charges break emulsions. This is the fundamental principle for many industrial and practical processes. Using micrometer-sized pH-sensitive polymeric hydrogel particles as emulsion stabilizers, we prepare emulsions that consist of oppositely charged droplets, which do not coalesce. We observe noncoalescence of oppositely charged droplets in bulk emulsification as well as in microfluidic devices, where oppositely charged droplets are forced to collide within channel junctions. The results demonstrate that electrostatic interactions between droplets do not determine their stability and reveal the unique pH-dependent properties of emulsions stabilized by soft microgel particles. The noncoalescence can be switched to coalescence by neutralizing the microgels, and the emulsion can be broken on demand. This unusual feature of the microgel-stabilized emulsions offers fascinating opportunities for future applications of these systems.

Liu, Tingting; Seiffert, Sebastian; Thiele, Julian; Abate, Adam R.; Weitz, David A.; Richtering, Walter

2012-01-01

473

VHMPID detector for the ALICE experiment upgrade at LHC  

NASA Astrophysics Data System (ADS)

Results from high energy nucleus-nucleus collisions at RHIC have shown the importance of particle identification in a very large momentum range, in particular for protons. The ALICE experiment has unique capabilities to identify particles; however its momentum coverage for track-by-track identification should be extended to meet new physics challenges at LHC. The Very High Momentum Charged Particle Identification (VHMPID) detector represents a possible upgrade of the ALICE experimental apparatus. It has been conceived to extend proton identification on a track-by-track basis up to p=30GeV/c. The VHMPID is a Ring Imaging Cherenkov with C4F10 gaseous radiator coupled to a CsI based photon detector. The focusing properties of a spherical mirror are exploited to focus Cherenkov photons on the photon detector. The detector layout and the expected performance will be discussed. First results from beam tests of a prototype of 60×40cm2 will be also presented.

Vhmpid Collaboration; Volpe, G.

2011-06-01

474